Patent Application
20210047536
The following generally relates to materials for forming a nucleation inhibiting coating for use in selectively depositing an electrically conductive coating on a surface. Specifically, optoelectronic devices incorporating such nucleation inhibiting coating and conductive coating are described.
Organic light emitting diodes (OLEDs) typically include several layers of organic materials interposed between conductive thin film electrodes, with at least one of the organic layers being an electroluminescent layer. When a voltage is applied to electrodes, holes and electrons are injected from an anode and a cathode, respectively. The holes and electrons injected by the electrodes migrate through the organic layers to reach the electroluminescent layer. When a hole and an electron are in close proximity, they are attracted to each other due to a Coulomb force. The hole and electron may then combine to form a bound state referred to as an exciton. An exciton may decay through a radiative recombination process, in which a photon is released. Alternatively, an exciton may decay through a non-radiative recombination process, in which no photon is released. It is noted that, as used herein, internal quantum efficiency (IQE) will be understood to be a proportion of all electron-hole pairs generated in a device which decay through a radiative recombination process.
A radiative recombination process can occur as a fluorescence or phosphorescence process, depending on a spin state of an electron-hole pair (namely, an exciton). Specifically, the exciton formed by the electron-hole pair may be characterized as having a singlet or triplet spin state. Generally, radiative decay of a singlet exciton results in fluorescence, whereas radiative decay of a triplet exciton results in phosphorescence.
More recently, other light emission mechanisms for OLEDs have been proposed and investigated, including thermally activated delayed fluorescence (TADF). Briefly, TADF emission occurs through a conversion of triplet excitons into singlet excitons via a reverse inter system crossing process with the aid of thermal energy, followed by radiative decay of the singlet excitons.
An external quantum efficiency (EQE) of an OLED device may refer to a ratio of charge carriers provided to the OLED device relative to a number of photons emitted by the device. For example, an EQE of 100% indicates that one photon is emitted for each electron that is injected into the device. As will be appreciated, an EQE of a device is generally substantially lower than an IQE of the device. The difference between the EQE and the IQE can generally be attributed to a number of factors such as absorption and reflection of light caused by various components of the device.
An OLED device can typically be classified as being either a “bottom-emission” or “top-emission” device, depending on a relative direction in which light is emitted from the device. In a bottom-emission device, light generated as a result of a radiative recombination process is emitted in a direction towards a base substrate of the device, whereas, in a top-emission device, light is emitted in a direction away from the base substrate. Accordingly, an electrode that is proximal to the base substrate is generally made to be light transmissive (e.g., substantially transparent or semi-transparent) in a bottom-emission device, whereas, in a top-emission device, an electrode that is distal to the base substrate is generally made to be light transmissive in order to reduce attenuation of light. Depending on the specific device structure, either an anode or a cathode may act as a transmissive electrode in top-emission and bottom-emission devices.
An OLED device also may be a double-sided emission device, which is configured to emit light in both directions relative to a base substrate. For example, a double-sided emission device may include a transmissive anode and a transmissive cathode, such that light from each pixel is emitted in both directions. In another example, a double-sided emission display device may include a first set of pixels configured to emit light in one direction, and a second set of pixels configured to emit light in the other direction, such that a single electrode from each pixel is transmissive.
In addition to the above device configurations, a transparent or semi-transparent OLED device also can be implemented, in which the device includes a transparent portion which allows external light to be transmitted through the device. For example, in a transparent OLED display device, a transparent portion may be provided in a non-emissive region between each neighboring pixels. In another example, a transparent OLED lighting panel may be formed by providing a plurality of transparent regions between emissive regions of the panel. Transparent or semi-transparent OLED devices may be bottom-emission, top-emission, or double-sided emission devices.
While either a cathode or an anode can be selected as a transmissive electrode, a typical top-emission device includes a light transmissive cathode. Materials which are typically used to form the transmissive cathode include transparent conducting oxides (TCOs), such as indium tin oxide (ITO) and zinc oxide (ZnO), as well as thin films, such as those formed by depositing a thin layer of silver (Ag), aluminum (Al), or various metallic alloys such as magnesium silver (Mg:Ag) alloy and ytterbium silver (Yb:Ag) alloy with compositions ranging from about 1:9 to about 9:1 by volume. A multi-layered cathode including two or more layers of TCOs and/or thin metal films also can be used.
Particularly in the case of thin films, a relatively thin layer thickness of up to about a few tens of nanometers contributes to enhanced transparency and favorable optical properties (e.g., reduced microcavity effects) for use in OLEDs. However, a reduction in the thickness of a transmissive electrode is accompanied by an increase in its sheet resistance. An electrode with a high sheet resistance is generally undesirable for use in OLEDs, since it creates a large current-resistance (IR) drop when a device is in use, which is detrimental to the performance and efficiency of OLEDs. The IR drop can be compensated to some extent by increasing a power supply level; however, when the power supply level is increased for one pixel, voltages supplied to other components are also increased to maintain proper operation of the device, and thus is unfavorable.
In order to reduce power supply specifications for top-emission OLED devices, solutions have been proposed to form busbar structures or auxiliary electrodes on the devices. For example, such an auxiliary electrode may be formed by depositing a conductive coating in electrical communication with a transmissive electrode of an OLED device. Such an auxiliary electrode may allow current to be carried more effectively to various regions of the device by lowering a sheet resistance and an associated IR drop of the transmissive electrode.
Since an auxiliary electrode is typically provided on top of an OLED stack including an anode, one or more organic layers, and a cathode, patterning of the auxiliary electrode is traditionally achieved using a shadow mask with mask apertures through which a conductive coating is selectively deposited, for example by a physical vapor deposition (PVD) process. However, since masks are typically metal masks, they have a tendency to warp during a high-temperature deposition process, thereby distorting mask apertures and a resulting deposition pattern. Furthermore, a mask is typically degraded through successive depositions, as a conductive coating adheres to the mask and obfuscates features of the mask. Consequently, such a mask should either be cleaned using time-consuming and expensive processes or should be disposed once the mask is deemed to be ineffective at producing the desired pattern, thereby rendering such process highly costly and complex. Accordingly, a shadow mask process may not be commercially feasible for mass production of OLED devices. Moreover, an aspect ratio of features which can be produced using the shadow mask process is typically constrained due to shadowing effects and a mechanical (e.g., tensile) strength of the metal mask, since large metal masks are typically stretched during a shadow mask deposition process.
Another challenge of patterning a conductive coating onto a surface through a shadow mask is that certain, but not all, patterns can be achieved using a single mask. As each portion of the mask is physically supported, not all patterns are possible in a single processing stage. For example, where a pattern specifies an isolated feature, a single mask processing stage typically cannot be used to achieve the desired pattern. In addition, masks which are used to produce repeating structures (e.g., busbar structures or auxiliary electrodes) spread across an entire device surface include a large number of perforations or apertures formed on the masks. However, forming a large number of apertures on a mask can compromise the structural integrity of the mask, thus leading to significant warping or deformation of the mask during processing, which can distort a pattern of deposited structures.
In addition to the above, when a common electrode having a substantially uniform thickness is provided as the top-emission cathode in an OLED display device, the optical performance of the device cannot readily be fine tuned according to the emission spectrum associated each subpixel. In a typical OLED display device, red, green, and blue subpixels are provided to form the pixels of the display device. The top-emission electrode used in such OLED display device is typically a common electrode coating a plurality of pixels. For example, such common electrode may be a relatively thin conductive layer having a substantially uniform thickness across the device. While efforts have been made to tune the optical microcavity effects associated with each subpixel color by varying the thickness of organic layers disposed within different subpixels, such approach may not provide sufficient degree of tuning of the optical microcavity effects in at least some cases. In addition, such approach may be difficult to implement in an OLED display production environment.
Some embodiments will now be described by way of example with reference to the appended drawings.
It will be appreciated that for simplicity and clarity of illustration, where considered appropriate, reference numerals may be repeated among the figures to indicate corresponding or analogous components. In addition, numerous specific details are set forth in order to provide a thorough understanding of example embodiments described herein. However, it will be understood by those of ordinary skill in the art that the example embodiments described herein may be practiced without some of those specific details. In other instances, certain methods, procedures and components have not been described in detail so as not to obscure the example embodiments described herein.
In one aspect according to some embodiments, a method for depositing an electrically conductive coating on a surface is provided. In some embodiments, the method is performed in the context of a manufacturing method of an opto-electronic device. In some embodiments, the method is performed in the context of a manufacturing method of another device. In some embodiments, the method includes depositing a nucleation inhibiting coating on a first region of a substrate to produce a patterned substrate. The patterned substrate includes the first region covered by the nucleation inhibiting coating, and a second region of the substrate that is exposed from, or is substantially free of or is substantially uncovered by, the nucleation inhibiting coating. The method also includes treating the patterned substrate to deposit the conductive coating on the second region of the substrate. In some embodiments, a material of the conductive coating includes magnesium. In some embodiments, treating the patterned substrate includes treating both the nucleation inhibiting coating and the second region of the substrate to deposit the conductive coating on the second region of the substrate, while the nucleation inhibiting coating remains exposed from, or is substantially free of or is substantially uncovered by, the conductive coating. In some embodiments, treating the patterned substrate includes performing evaporation or sublimation of a source material used to form the conductive coating, and exposing both the nucleation inhibiting coating and the second region of the substrate to the evaporated source material.
As used herein, the term “nucleation inhibiting” is used to refer to a coating or a layer of a material having a surface which exhibits a relatively low affinity towards deposition of an electrically conductive material, such that the deposition of the conductive material on the surface is inhibited, while the term “nucleation promoting” is used to refer to a coating or a layer of a material having a surface which exhibits a relatively high affinity towards deposition of an electrically conductive material, such that the deposition of the conductive material on the surface is facilitated. One measure of nucleation inhibiting or nucleation promoting property of a surface is an initial sticking probability of the surface for an electrically conductive material, such as magnesium. For example, a nucleation inhibiting coating with respect to magnesium can refer to a coating having a surface which exhibits a relatively low initial sticking probability for magnesium vapor, such that deposition of magnesium on the surface is inhibited, while a nucleation promoting coating with respect to magnesium can refer to a coating having a surface which exhibits a relatively high initial sticking probability for magnesium vapor, such that deposition of magnesium on the surface is facilitated. As used herein, the terms “sticking probability” and “sticking coefficient” may be used interchangeably. Another measure of nucleation inhibiting or nucleation promoting property of a surface is an initial deposition rate of an electrically conductive material, such as magnesium, on the surface relative to an initial deposition rate of the conductive material on another (reference) surface, where both surfaces are subjected or exposed to an evaporation flux of the conductive material.
As used herein, the terms “evaporation” and “sublimation” are interchangeably used to generally refer to deposition processes in which a source material is converted into a vapor (e.g., by heating) to be deposited onto a target surface in, for example, a solid state.
As used herein, a surface (or a certain area of the surface) which is “substantially free of” or “is substantially uncovered by” a material refers to a substantial absence of the material on the surface (or the certain area of the surface). Specifically, regarding an electrically conductive coating, one measure of an amount of an electrically conductive material on a surface is a light transmittance, since electrically conductive materials, such as metals including magnesium, attenuate and/or absorb light. Accordingly, a surface can be deemed to be substantially free of an electrically conductive material if the light transmittance is greater than 90%, greater than 92%, greater than 95%, or greater than 98% in the visible portion of the electromagnetic spectrum. Another measure of an amount of a material on a surface is a percentage coverage of the surface by the material, such as where the surface can be deemed to be substantially free of the material if the percentage coverage by the material is no greater than 10%, no greater than 8%, no greater than 5%, no greater than 3%, or no greater than 1%. Surface coverage can be assessed using imaging techniques, such as using transmission electron microscopy, atomic force microscopy, or scanning electron microscopy.
As illustrated in
As such, when the stamp 210 is moved away from the substrate 100 as illustrated in
Once a nucleation inhibiting coating has been deposited on a region of a surface of a substrate, a conductive coating may be deposited on remaining uncovered region(s) of the surface where the nucleation inhibiting coating is not present. Turning to
It will be appreciated that although shadow mask patterning and micro-contact transfer printing processes have been illustrated and described above, other processes may be used for selectively patterning a substrate by depositing a nucleation inhibiting material. Various additive and subtractive processes of patterning a surface may be used to selectively deposit a nucleation inhibiting coating. Examples of such processes include, but are not limited to, photolithography, printing (including ink or vapor jet printing and reel-to-reel printing), organic vapor phase deposition (OVPD), and laser induced thermal imaging (LM) patterning, and combinations thereof.
In some applications, it may be desirable to deposit a conductive coating having specific material properties onto a substrate surface on which the conductive coating cannot be readily deposited. For example, pure or substantially pure magnesium typically cannot be readily deposited onto some organic surface due to low sticking coefficients of magnesium on some organic surfaces. Accordingly, in some embodiments, the substrate surface is further treated by depositing a nucleation promoting coating thereon prior to depositing the conductive coating.
Based on findings and experimental observations, it is postulated that fullerenes and other nucleation promoting materials, as will be explained further herein, act as nucleation sites for the deposition of a conductive coating including magnesium. For example, in cases where magnesium is deposited using an evaporation process on a fullerene treated surface, the fullerene molecules act as nucleation sites that promote formation of stable nuclei for magnesium deposition. Less than a monolayer of fullerene or other nucleation promoting material may be provided on the treated surface to act as nucleation sites for deposition of magnesium in some cases. As will be understood, treating the surface by depositing several monolayers of a nucleation promoting material may result in a higher number of nucleation sites, and thus a higher initial sticking probability. Other examples of nucleation promoting materials include, but are not limited to, metals such as Ag and Yb, and metal oxides such as ITO (indium tin oxide) and IZO (indium zinc oxide).
It will also be appreciated that an amount of fullerene or other material deposited on a surface may be more, or less, than one monolayer. For example, the surface may be treated by depositing 0.1 monolayer, 1 monolayer, 10 monolayers, or more of a nucleation promoting material or a nucleation inhibiting material. As used herein, depositing 1 monolayer of a material refers to an amount of the material to cover a desired area of a surface with a single layer of constituent molecules or atoms of the material. Similarly, as used herein, depositing 0.1 monolayer of a material refers to an amount of the material to cover 10% of a desired area of a surface with a single layer of constituent molecules or atoms of the material. Due to, for example, possible stacking or clustering of molecules or atoms, an actual thickness of a deposited material may be non-uniform. For example, depositing 1 monolayer of a material may result in some regions of a surface being uncovered by the material, while other regions of the surface may have multiple atomic or molecular layers deposited thereon. In some embodiments, the thickness of the nucleation promoting coating may be between about 1 nm and about 5 nm or between about 1 nm and about 3 nm.
As used herein, the term “fullerene” refers to a material including carbon molecules. Examples of fullerene molecules include carbon cage molecules including a three-dimensional skeleton that includes multiple carbon atoms, which form a closed shell, and which can be spherical or semi-spherical in shape. A fullerene molecule can be designated as Cn, where n is an integer corresponding to a number of carbon atoms included in a carbon skeleton of the fullerene molecule. Examples of fullerene molecules include Cn, where n is in the range of 50 to 250, such as C60, C70, C72, C74, C76, C78, C80, C82, and C84. Additional examples of fullerene molecules include carbon molecules in a tube or cylindrical shape, such as single-walled carbon nanotubes and multi-walled carbon nanotubes.
In
While the nucleation inhibiting coating 140 is illustrated as being deposited by evaporation, it will be appreciated that other deposition and surface coating techniques may be used, including but not limited to spin coating, dip coating, printing, spray coating, OVPD, LITI patterning, physical vapor deposition (PVD) (including sputtering), chemical vapor deposition (CVD), and combinations thereof.
In
In
In
In the foregoing embodiments, it will be appreciated that the conductive coating 440 formed by the processes may be used as an electrode or a conductive structure for an electronic device. For example, the conductive coating 440 may be an anode or a cathode of an organic opto-electronic device, such as an OLED device or an organic photovoltaic (OPV) device. In addition, the conductive coating 440 may also be used as an electrode for opto-electronic devices including quantum dots as an active layer material. For example, such a device may include an active layer disposed between a pair of electrodes with the active layer including quantum dots. The device may be, for example, an electroluminescent quantum dot display device in which light is emitted from the quantum dot active layer as a result of current provided by the electrodes. The conductive coating 440 may also be a busbar or an auxiliary electrode for any of the foregoing devices.
Accordingly, it will be appreciated that the substrate 100 onto which various coatings are deposited may include one or more additional organic and/or inorganic layers not specifically illustrated or described in the foregoing embodiments. For example, in the case of an OLED device, the substrate 100 may include one or more electrodes (e.g., an anode and/or a cathode), charge injection and/or transport layers, and an electroluminescent layer. The substrate 100 may further include one or more transistors and other electronic components such as resistors and capacitors, which are included in an active-matrix or a passive-matrix OLED device. For example, the substrate 100 may include one or more top-gate thin-film transistors (TFTs), one or more bottom-gate TFTs, and/or other TFT structures. A TFT may be an n-type TFT or a p-type TFT. Examples of TFT structures include those including amorphous silicon (a-Si), indium gallium zinc oxide (IGZO), and low-temperature polycrystalline silicon (LTPS).
The substrate 100 may also include a base substrate for supporting the above-identified additional organic and/or inorganic layers. For example, the base substrate may be a flexible or rigid substrate. The base substrate may include, for example, silicon, glass, metal, polymer (e.g., polyimide), sapphire, or other materials suitable for use as the base substrate.
The surface 102 of the substrate 100 may be an organic surface or an inorganic surface. For example, if the conductive coating 440 is for use as a cathode of an OLED device, the surface 102 may be a top surface of a stack of organic layers (e.g., a surface of an electron injection layer). In another example, if the conductive coating 440 is for use as an auxiliary electrode of a top-emission OLED device, the surface 102 may be a top surface of an electrode (e.g., a common cathode). Alternatively, such an auxiliary electrode may be formed directly beneath a transmissive electrode on top of a stack of organic layers.
The hole injection layer 612 may be formed using a hole injection material which generally facilitates the injection of holes by the anode 614. The hole transport layer 610 may be formed using a hole transport material, which is generally a material that exhibits high hole mobility.
The electroluminescent layer 608 may be formed, for example, by doping a host material with an emitter material. The emitter material may be a fluorescent emitter, a phosphorescent emitter, or a TADF emitter, for example. A plurality of emitter materials may also be doped into the host material to form the electroluminescent layer 608.
The electron transport layer 606 may be formed using an electron transport material which generally exhibits high electron mobility. The electron injection layer 604 may be formed using an electron injection material, which generally acts to facilitate the injection of electrons by the cathode 602.
It will be understood that the structure of the device 600 may be varied by omitting or combining one or more layers. Specifically, one or more of the hole injection layer 612, the hole transport layer 610, the electron transport layer 606, and the electron injection layer 604 may be omitted from the device structure. One or more additional layers may also be present in the device structure. Such additional layers include, for example, a hole blocking layer, an electron blocking layer, and additional charge transport and/or injection layers. Each layer may further include any number of sub-layers, and each layer and/or sub-layer may include various mixtures and composition gradients. It will also be appreciated that the device 600 may include one or more layers containing inorganic and/or organometallic materials, and is not limited to devices composed solely of organic materials. For example, the device 600 may include quantum dots.
The device 600 may be connected to a power source 620 for supplying current to the device 600.
In another embodiment where the device 600 is an EL quantum dot device, the EL layer 608 generally includes quantum dots, which emit light when current is supplied.
In another embodiment, deposition of the nucleation inhibiting coating in stage 706 may be conducted using an open mask, or without a mask. In yet another embodiment, deposition of the nucleation promoting coating in step 708 may be conducted prior to deposition of the nucleation inhibiting coating in step 706. In yet another embodiment, deposition of the nucleation promoting coating in step 708 may be conducted using an open mask, or without a mask, prior to selective deposition of the nucleation inhibiting coating in step 706.
For the sake of simplicity and clarity, details of deposited materials including thickness profiles and edge profiles have been omitted from the process diagrams.
In accordance with the above-described embodiments, a conductive coating may be selectively deposited on target regions using an open mask or a mask-free deposition process, through the use of a nucleation inhibiting coating or a combination of nucleation inhibiting and nucleation promoting coatings.
It will also be appreciated that an open mask used for deposition of any of various layers or coatings, including a conductive coating, a nucleation inhibiting coating, and a nucleation promoting coating, may “mask” or prevent deposition of a material on certain regions of a substrate. However, unlike a fine metal mask (FMM) used to form relatively small features with a feature size on the order of tens of microns or smaller, a feature size of an open mask is generally comparable to the size of an OLED device being manufactured. For example, the open mask may mask edges of a display device during manufacturing, which would result in the open mask having an aperture that approximately corresponds to a size of the display device (e.g. about 1 inch for micro-displays, about 4-6 inches for mobile displays, about 8-17 inches for laptop or tablet displays, and so forth). For example, the feature size of an open mask may be on the order of about 1 cm or greater. Accordingly, an aperture formed in an open mask is typically sized to encompass a plurality of emissive regions or pixels, which together form the display device.
While outer-most pixels have been illustrated as being masked in the examples of
In various embodiments described herein, it will be understood that the use of an open mask may be omitted, if desired. Specifically, an open mask deposition process described herein may alternatively be conducted without the use of a mask, such that an entire target surface is exposed.
At least some of the above embodiments have been described in reference to various layers or coatings, including a nucleation promoting coating, a nucleation inhibiting coating, and a conductive coating, being formed using an evaporation process. As will be understood, an evaporation process is a type of PVD process where one or more source materials are evaporated or sublimed under a low pressure (e.g., vacuum) environment and deposited on a target surface through de-sublimation of the one or more evaporated source materials. A variety of different evaporation sources may be used for heating a source material, and, as such, it will be appreciated that the source material may be heated in various ways. For example, the source material may be heated by an electric filament, electron beam, inductive heating, or by resistive heating. In addition, such layers or coatings may be deposited and/or patterned using other suitable processes, including photolithography, printing, OVPD, LM patterning, and combinations thereof. These processes may also be used in combination with a shadow mask to achieve various patterns.
Although certain processes have been described with reference to evaporation for purposes of depositing a nucleation promoting material, a nucleation inhibiting material, and the conductive coating, it will be appreciated that various other processes may be used to deposit these materials. For example, deposition may be conducted using other PVD processes (including sputtering), CVD processes (including plasma enhanced chemical vapor deposition (PECVD)), or other suitable processes for depositing such materials. In some embodiments, the conductive coating is deposited by heating a source material for forming the conductive coating using a resistive heater. In other embodiments, the conductive coating source material may be loaded in a heated crucible, a heated boat, a Knudsen cell (e.g., an effusion evaporator source), or any other type of evaporation source.
A deposition source material used to deposit a conductive coating may be a mixture or a compound, and, in some embodiments, at least one component of the mixture or compound is not deposited on a substrate during deposition (or is deposited in a relatively small amount compared to, for example, magnesium). In some embodiments, the source material may be a copper-magnesium (Cu—Mg) mixture or a Cu—Mg compound. In some embodiments, the source material for a magnesium deposition source includes magnesium and a material with a lower vapor pressure than magnesium, such as, for example, Cu. In other embodiments, the source material for a magnesium deposition source is substantially pure magnesium. Specifically, substantially pure magnesium can exhibit substantially similar properties (e.g., initial sticking probabilities on nucleation inhibiting and promoting coatings) compared to pure magnesium (99.99% and higher purity magnesium). For example, an initial sticking probability of substantially pure magnesium on a nucleation inhibiting coating can be within ±10% or within ±5% of an initial sticking probability of 99.99% purity magnesium on the nucleation inhibiting coating. Purity of magnesium may be about 95% or higher, about 98% or higher, about 99% or higher, or about 99.9% or higher. Deposition source materials used to deposit a conductive coating may include other metals in place of, or in combination with, magnesium. For example, a source material may include high vapor pressure materials, such as ytterbium (Yb), cadmium (Cd), zinc (Zn), or any combination thereof.
Furthermore, it will be appreciated that the processes of various embodiments may be performed on surfaces of other various organic or inorganic materials used as an electron injection layer, an electron transport layer, an electroluminescent layer, and/or a pixel definition layer (PDL) of an organic opto-electronic device. Examples of such materials include organic molecules as well as organic polymers such as those described in PCT Publication No. WO 2012/016074. It will also be understood by persons skilled in the art that organic materials doped with various elements and/or inorganic compounds may still be considered to be an organic material. It will further be appreciated by those skilled in the art that various organic materials may be used, and the processes described herein are generally applicable to an entire range of such organic materials.
It will also be appreciated that an inorganic substrate or surface can refer to a substrate or surface primarily including an inorganic material. For greater clarity, an inorganic material will generally be understood to be any material that is not considered to be an organic material. Examples of inorganic materials include metals, glasses, and minerals. Specifically, a conductive coating including magnesium may be deposited using a process according to the present disclosure on surfaces of lithium fluoride (LiF), glass and silicon (Si). Other surfaces on which the processes according to the present disclosure may be applied include those of silicon or silicone-based polymers, inorganic semiconductor materials, electron injection materials, salts, metals, and metal oxides.
It will be appreciated that a substrate may include a semiconductor material, and, accordingly, a surface of such a substrate may be a semiconductor surface. A semiconductor material may be described as a material which generally exhibits a band gap. For example, such a band gap may be formed between a highest occupied molecular orbital (HOMO) and a lowest unoccupied molecular orbital (LUMO). Semiconductor materials thus generally possess electrical conductivity that is less than that of a conductive material (e.g., a metal) but greater than that of an insulating material (e.g., a glass). It will be understood that a semiconductor material may be an organic semiconductor material or an inorganic semiconductor material.
The auxiliary electrode 1670 is electrically connected to the cathode 1650. Particularly in a top-emission configuration, it is desirable to deposit a relatively thin layer of the cathode 1650 to reduce optical interference (e.g., attenuation, reflection, diffusion, and so forth) due to the presence of the cathode 1650. However, a reduced thickness of the cathode 1650 generally increases a sheet resistance of the cathode 1650, thus reducing the performance and efficiency of the OLED device 1600. By providing the auxiliary electrode 1670 that is electrically connected to the cathode 1650, the sheet resistance and thus the IR drop associated with the cathode 1650 can be decreased. Furthermore, by selectively depositing the auxiliary electrode 1670 to cover certain regions of the device area while other regions remain uncovered, optical interference due to the presence of the auxiliary electrode 1670 may be controlled and/or reduced.
While the advantages of auxiliary electrodes have been explained in reference to top-emission OLED devices, it may also be advantageous to selectively deposit an auxiliary electrode over a cathode of a bottom-emission or double-sided emission OLED device. For example, while the cathode may be formed as a relatively thick layer in a bottom-emission OLED device without substantially affecting optical characteristics of the device, it may still be advantageous to form a relatively thin cathode. For example, in a transparent or semi-transparent display device, layers of the entire device including a cathode can be formed to be substantially transparent or semi-transparent. Accordingly, it may be beneficial to provide a patterned auxiliary electrode which cannot be readily detected by a naked eye from a typical viewing distance. It will also be appreciated that the described processes may be used to form busbars or auxiliary electrodes for decreasing a resistance of electrodes for devices other than OLED devices.
While thicknesses of the nucleation inhibiting coating 1771 and the cathode 1712 may be varied depending on the desired application and performance, at least in some embodiments, the thickness of the nucleation inhibiting coating 1771 may be comparable to, or substantially less than, the thickness of the cathode 1712 as illustrated in
For comparative purposes, an example of a comparative PMOLED device 1719 is illustrated in
In the comparative PMOLED device 1719 illustrated in
While the patterned cathode 1712 shown in
In
In
In
While the auxiliary electrode has been illustrated as being formed as a connected and continuous structure in the embodiment of
Auxiliary electrodes may be used in display devices with various pixel or sub-pixel arrangements. For example, auxiliary electrodes may be provided on a display device in which a diamond pixel arrangement is used. Examples of such pixel arrangements are illustrated in
In another aspect according to some embodiments, a device is provided. In some embodiments, the device is an opto-electronic device. In some embodiments, the device is another electronic device or other product. In some embodiments, the device includes a substrate, a nucleation inhibiting coating, and a conductive coating. The nucleation inhibiting coating covers a first region of the substrate. The conductive coating covers a second region of the substrate, and partially overlaps the nucleation inhibiting coating such that at least a portion of the nucleation inhibiting coating is exposed from, or is substantially free of or is substantially uncovered by, the conductive coating. In some embodiments, the conductive coating includes a first portion and a second portion, the first portion of the conductive coating covers the second region of the substrate, and the second portion of the conductive coating overlaps a portion of the nucleation inhibiting coating. In some embodiments, the second portion of the conductive coating is spaced from the nucleation inhibiting coating by a gap. In some embodiments, the nucleation inhibiting coating includes an organic material. In some embodiments, the first portion of the conductive coating and the second portion of the conductive coating are formed integral or continuous with one another to provide a single monolithic structure.
In another aspect according to some embodiments, a device is provided. In some embodiments, the device is an opto-electronic device. In some embodiments, the device is another electronic device or other product. In some embodiments, the device includes a substrate and a conductive coating. The substrate includes a first region and a second region. The conductive coating covers the second region of the substrate, and partially overlaps the first region of the substrate such that at least a portion of the first region of the substrate is exposed from, or is substantially free of or is substantially uncovered by, the conductive coating. In some embodiments, the conductive coating includes a first portion and a second portion, the first portion of the conductive coating covers the second region of the substrate, and the second portion of the conductive coating overlaps a portion of the first region of the substrate. In some embodiments, the second portion of the conductive coating is spaced from the first region of the substrate by a gap. In some embodiments, the first portion of the conductive coating and the second portion of the conductive coating are integrally formed with one another.
Particularly in the case where the nucleation inhibiting coating 3420 is formed such that its surface 3422 exhibits a relatively low affinity or initial sticking probability against a material used to form the conductive coating 3430, there is a gap 3441 formed between the overlapping, second portion 3434 of the conductive coating 3430 and the surface 3422 of the nucleation inhibiting coating 3420. Accordingly, the second portion 3434 of the conductive coating 3430 is not in direct physical contact with the nucleation inhibiting coating 3420, but is spaced from the nucleation inhibiting coating 3420 by the gap 3441 along the direction perpendicular to the surface 3417 of the substrate 3410 as indicated by arrow 3490. Nevertheless, the first portion 3432 of the conductive coating 3430 may be in direct physical contact with the nucleation inhibiting coating 3420 at an interface or a boundary between the first region 3415 and the second region 3412 of the substrate 3410.
In some embodiments, the overlapping, second portion 3434 of the conductive coating 3430 may laterally extend over the nucleation inhibiting coating 3420 by a comparable extent as a thickness of the conductive coating 3430. For example, in reference to
In another embodiment illustrated in
In yet another embodiment illustrated in
In yet another embodiment illustrated in
While details regarding certain features of the device and the conductive coating 3430 have been omitted in the above description for the embodiments of
It has been observed that, at least in some cases, conducting the open mask or mask-free deposition of the conductive coating 3430 over a substrate surface which has been partially coated with the nucleation inhibiting coating 3420 can result in the formation of the conductive coating 3430 exhibiting a tapered cross-sectional profile at or near the interface between the conductive coating 3430 and the nucleation inhibiting coating 3420.
During the nucleation stage of the thin film formation process, molecules in the vapor phase condense onto the surface of the substrate to form nuclei. Without wishing to be bound by a particular theory, it is postulated that the shapes and sizes of these nuclei and the subsequent growth of these nuclei into islands and then into a thin film, depend on a number of factors, such as the interfacial tensions between the vapor, substrate, and the condensed film nuclei. It is further postulated that, during thin film nucleation and growth at or near the interface between the exposed surface of the substrate and the nucleation inhibiting coating, a relatively high contact angle between the edge of the film and the substrate would be observed due to “dewetting” of the solid surface of the of the thin film by the nucleation inhibiting coating. This dewetting property is driven by the minimization of surface energy between the substrate, thin film, vapor and nucleation inhibiting layer. Accordingly, it is postulated that the presence of the nucleation inhibiting coating and the properties of the nucleation inhibiting coating have a significant effect on the nuclei formation and the growth mode of the edge of the conductive coating.
It has been observed that the “contact angle” of the conductive coating 3430 at or near the interface between the conductive coating 3430 and the nucleation inhibiting coating 3420 vary depending on properties of the nucleation inhibiting coating 3420, such as the relative affinity or the initial sticking probability. It is further postulated that the contact angle of the nuclei may dictate the thin film contact angle of the conductive coating formed by deposition. Referring to
In some embodiments, the contact angle of the conductive coating 3430 may be greater than about 90 degrees. Referring now to
In at least some applications, it may be particularly advantageous to form a conductive coating 3430 exhibiting a relatively high contact angle. For example, the contact angle of greater than about 10 degrees, greater than about 15 degrees, greater than about 20 degrees, greater than about 25 degrees, greater than about 30 degrees, greater than about 35 degrees, greater than about 40 degrees, greater than about 50 degrees, greater than about 60 degrees, greater than about 70 degrees, greater than about 75 degrees, or greater than about 80 degrees. For example, conductive coating 3430 having a relatively high contact angle may be particularly advantageous for creating finely patterned features while maintaining a relatively high aspect ratio. In some applications, it may be preferable to form a conductive coating 3430 exhibiting a contact angle greater than about 90 degrees. For example, the contact angle of greater than about 90 degrees, greater than about 95 degrees, greater than about 100 degrees, greater than about 105 degrees, greater than about 110 degrees, greater than about 120 degrees, greater than about 130 degrees, greater than about 135 degrees, greater than about 140 degrees, greater than about 145 degrees, greater than about 150 degrees, or greater than about 160 degrees.
As described above, it is postulated that the contact angle of the conductive coating is determined based at least partially on the properties (e.g. initial sticking probability) of the nucleation inhibiting coating disposed adjacent to the area onto which the conductive coating is formed. Accordingly, nucleation inhibiting coating materials which allow selective deposition of conductive coating exhibiting relatively high contact angle may be particularly useful in certain applications.
Without wishing to be bound by a particular theory, it is postulated that the relationship among the various interfacial tensions present during nucleation and growth is dictated according to the following equation, which is also referred to as the Young's equation in capillarity theory:
γsv=γfs+γvf cos θ
wherein γsv corresponds to the interfacial tension between substrate and vapor, γfs corresponds to the interfacial tension between the film and the substrate, γvf corresponds to the interfacial tension between the vapor and film, and θ is the film nucleus contact angle.
On the basis of Young's equation, it can be derived that, for island growth, the film nucleus contact angle θ is greater than zero and therefore γsv<γfs+γvf.
For layer growth wherein the deposited film “wets” the substrate, the nucleus contact angle θ=0 and therefore γsv=γfs+γvf.
For Stranski-Krastanov (S-K) growth, wherein the strain energy per unit area of the film overgrowth is large with respect to the interfacial tension between the vapor and the film, γsv>γfs+γvf.
It is postulated that the nucleation and growth mode of the conductive coating at an interface between the nucleation inhibiting coating and the exposed substrate surface follows the island growth model, wherein θ>0. Particularly in cases where the nucleation inhibiting coating exhibits a relatively low affinity or low initial sticking probability (i.e. dewetting) towards the material used to form the conductive coating, resulting in a relatively high thin film contact angle of the conductive coating. On the contrary, when a conductive coating is selectively deposited on a surface without the use of a nucleation inhibiting coating, for example by employing a shadow mask, the nucleation and growth mode of the conductive coating may differ. In particular, it has been observed that the conductive coating formed using a shadow mask patterning process may, at least in some cases, exhibit relatively low thin film contact angle of less than about 10 degrees.
It will be appreciated that, while not explicitly illustrated, a material used to form the nucleation inhibiting coating 3420 may also be present to some extent at an interface between the conductive coating 3430 and an underlying surface (e.g., a surface of the nucleation promoting layer 3451 or the substrate 3410). Such material may be deposited as a result of a shadowing effect, in which a deposited pattern is not identical to a pattern of a mask and may result in some evaporated material being deposited on a masked portion of a target surface. For example, such material may form as islands or disconnected clusters, or as a thin film having a thickness that is substantially less than an average thickness of the nucleation inhibiting coating 3420.
In the case of
In some embodiments, the nucleation inhibiting coating 3420 may be removed subsequent to deposition of the conductive coating 3430, such that at least a portion of an underlying surface covered by the nucleation inhibiting coating 3420 in the embodiments of
A device of some embodiments may be an electronic device, and, more specifically, an opto-electronic device. An opto-electronic device generally encompasses any device that converts electrical signals into photons or vice versa. As such, an organic opto-electronic device can encompass any opto-electronic device where one or more active layers of the device are formed primarily of an organic material, and, more specifically, an organic semiconductor material. Examples of organic opto-electronic devices include, but are not limited to, OLED devices and OPV devices.
It will also be appreciated that organic opto-electronic devices may be formed on various types of base substrates. For example, a base substrate may be a flexible or rigid substrate. The base substrate may include, for example, silicon, glass, metal, polymer (e.g., polyimide), sapphire, or other materials suitable for use as the base substrate.
It will also be appreciated that various components of a device may be deposited using a wide variety of techniques, including vapor deposition, spin-coating, line coating, printing, and various other deposition techniques.
In some embodiments, an organic opto-electronic device is an OLED device, wherein an organic semiconductor layer includes an electroluminescent layer. In some embodiments, the organic semiconductor layer may include additional layers, such as an electron injection layer, an electron transport layer, a hole transport layer, and/or a hole injection layer. For example, the OLED device may be an AMOLED device, PMOLED device, or an OLED lighting panel or module. Furthermore, the opto-electronic device may be a part of an electronic device. For example, the opto-electronic device may be an OLED display module of a computing device, such as a smartphone, a tablet, a laptop, or other electronic device such as a monitor or a television set.
In some embodiments, an opto-electronic device is an OLED device, wherein the device generally includes an anode, an organic semiconductor layer and a cathode.
The device 3802 includes a base substrate 3810, and a buffer layer 3812 deposited over a surface of the base substrate 3810. A thin-film transistor (TFT) 3804 is then formed over the buffer layer 3812. Specifically, a semiconductor active area 3814 is formed over a portion of the buffer layer 3812, and a gate insulating layer 3816 is deposited to substantially cover the semiconductor active area 3814. Next, a gate electrode 3818 is formed on top of the gate insulating layer 3816, and an interlayer insulating layer 3820 is deposited. A source electrode 3824 and a drain electrode 3822 are formed such that they extend through openings formed through the interlayer insulating layer 3820 and the gate insulating layer 3816 to be in contact with the semiconductor active layer 3814. An insulating layer 3842 is then formed over the TFT 3804. A first electrode 3844 is then formed over a portion of the insulating layer 3842. As illustrated in
In
While the auxiliary electrode 3856 or 4056 is illustrated as not being in direct physical contact with the second electrode 3850 or 4050 in the embodiments of
While not shown, the AMOLED device 4102 of
In the device 4300, the light transmissive region 4351 is substantially free of any materials which may substantially affect the transmission of light there through. In particular, the TFT 4308, the anode 4344, and the auxiliary electrode 4361 are all positioned within the subpixel region 4331 such that these components do not attenuate or impede light from being transmitted through the light transmissive region 4351. Such arrangement allows a viewer viewing the device 4300 from a typical viewing distance to see through the device 4300 when the pixels are off or are non-emitting, thus creating a transparent AMOLED display.
While not shown, the AMOLED device 4300 of
In other embodiments, various layers or coatings, including the organic layers 4348 and the cathode 4350, may cover a portion of the light transmissive region 4351 if such layers or coatings are substantially transparent. Alternatively, the PDLs 4346a, 4346b may not be provided in the light transmissive region 4351, if desired.
It will be appreciated that pixel and subpixel arrangements other than the arrangement illustrated in
In some embodiments, the thickness of the first conductive coating 4350 is less than the thickness of the second conductive coating 4352. In this way, relatively high light transmittance may be maintained in the light transmissive region 4351. For example, the thickness of the first conductive coating 4350 may be, for example, less than about 30 nm, less than about 25 nm, less than about 20 nm, less than about 15 nm, less than about 10 nm, less than about 8 nm, or less than about 5 nm, and the thickness of the second conductive coating 4352 may be, for example, less than about 30 nm, less than about 25 nm, less than about 20 nm, less than about 15 nm, less than about 10 nm, or less than about 8 nm. In other embodiments, the thickness of the first conductive coating 4350 is greater than the thickness of the second conductive coating 4352. In yet another embodiment, the thickness of the first conductive coating 4350 and the thickness of the second conductive coating 4352 may substantially be about the same.
The material(s) which may be used to form the first conductive coating 4350 and the second conductive coating 4352 may be substantially the same as those used to form the first conductive coating 1371 and the second conductive coating 1372, respectively. Since such materials have been described above in relation to other embodiments, descriptions of these materials are omitted for sake of brevity.
In the device 4300, the light transmissive region 4351 is substantially free of any materials which may substantially affect the transmission of light there through. In particular, the TFT 4308, the anode 4344, and an auxiliary electrode are all positioned within the subpixel region 4331 such that these components do not attenuate or impede light from being transmitted through the light transmissive region 4351. Such arrangement allows a viewer viewing the device 4300 from a typical viewing distance to see through the device 4300 when the pixels are off or are non-emitting, thus creating a transparent AMOLED display.
In some embodiments, an electrode of an AMOLED device may be patterned. For example, a conductive coating which has been selectively deposited using the processes described above in various embodiments may act as an electrode (e.g. cathode) of an AMOLED device.
Accordingly, in one embodiment, a light-emitting opto-electronic device is provided, the device including: an emissive region and a non-emissive region; a nucleation inhibition coating disposed in at least a portion of the non-emissive region; and a conductive coating disposed in the emissive region. In a further embodiment, the emissive region includes a first electrode, a semiconducting layer disposed over the first electrode, and the conductive coating disposed over the semiconducting layer. In this way, for example, the first electrode may act as an anode and the conductive coating may act as a cathode of the opto-electronic device. In such embodiments, the surface of the nucleation inhibiting coating in the non-emissive region may be substantially free of, or exposed from the conductive coating. In a yet further embodiment, a nucleation promoting coating may be disposed between the semiconducting layer and the conductive coating. It will be appreciated that the light-emitting opto-electronic device may be an AMOLED device, which may further include other layers, coatings, and components described herein in relation to such devices (including but not limited to TFTs, encapsulation, etc.) For example, the conductive coating disposed in the emissive region may have a thickness of less than about 40 nm, for example between about 5 nm and about 30 nm, between about 10 nm and about 25 nm, or between about 15 nm and about 25 nm. In some examples, the non-emissive region may include a light transmissive region.
While not shown, the AMOLED device 4300 of
In some embodiments, the nucleation inhibiting coating 4362 may be formed concurrently with at least one of the organic layers 4348. For example, the material for forming the nucleation inhibiting coating 4362 may also be used to form at least one of the organic layers 4348. In this way, the number of stages for fabricating the device 4300 or 4300′ may be reduced.
In some embodiments, additional conductive coatings, including the second conductive coating and the third conductive coating, which have been described in relation to other embodiments above, may also be provided over subpixels 4333, 4335, and 4337. Additionally, in some embodiments, an auxiliary electrode may also be provided in non-emissive regions of the device 4300, 4300′. For example, such auxiliary electrode may be provided in the regions between neighboring pixels 4321 such that it does not substantially affect the light transmittance in the subpixel regions 4331 or the light transmissive regions 4351. The auxiliary electrode may also be provided in the region between the subpixel region 4331 and the light transmissive region 4351, and/or be provided between neighboring subpixels, if desired. For example, referring to the embodiment of
In some embodiments, various layers or coatings, including the organic layers 4348, may cover a portion of the light transmissive region 4351 if such layers or coatings are substantially transparent. Alternatively, the PDLs 4346a, 4346b may be omitted from the light transmissive region 4351, if desired.
It will be appreciated that pixel and subpixel arrangements other than the arrangement illustrated in
In the foregoing embodiments, a nucleation inhibiting coating may, in addition to inhibiting nucleation and deposition of a conductive material (e.g., magnesium) thereon, act to enhance an out-coupling of light from a device. Specifically, the nucleation inhibiting coating may act as an index-matching coating, capping layer (CPL), and/or an anti-reflective coating.
A barrier coating (not shown) may be provided to encapsulate the devices illustrated in the foregoing embodiments depicting AMOLED display devices. As will be appreciated, such a barrier coating may inhibit various device layers, including organic layers and a cathode which may be prone to oxidation, from being exposed to moisture and ambient air. For example, the barrier coating may be a thin film encapsulation formed by printing, CVD, sputtering, ALD, any combinations of the foregoing, or by any other suitable methods. The barrier coating may also be provided by laminating a pre-formed barrier film onto the devices using an adhesive. For example, the barrier coating may be a multi-layer coating comprising organic materials, inorganic materials, or combination of both. The barrier coating may further comprise a getter material and/or a desiccant in some embodiments.
A sheet resistance specification for a common electrode of an AMOLED display device may vary according to a size of the display device (e.g., a panel size) and a tolerance for voltage variation. In general, the sheet resistance specification increases (e.g., a lower sheet resistance is specified) with larger panel sizes and lower tolerances for voltage variation across a panel.
The sheet resistance specification and an associated thickness of an auxiliary electrode to comply with the specification according to an embodiment were calculated for various panel sizes. The sheet resistances and the auxiliary electrode thicknesses were calculated for voltage tolerances of 0.1 V and 0.2 V. For the purpose of the calculation, an aperture ratio of 0.64 was assumed for all display panel sizes.
The specified thickness of the auxiliary electrode at example panel sizes are summarized in Table 2 below.
As will be understood, various layers and portions of a backplane, including a thin-film transistor (TFT) (e.g., TFT 3804 shown in
Furthermore, while a top-gate TFT has been illustrated and described in certain embodiments above, it will be appreciated that other TFT structures may also be used. For example, the TFT may be a bottom-gate TFT. The TFT may be an n-type TFT or a p-type TFT. Examples of TFT structures include those utilizing amorphous silicon (a-Si), indium gallium zinc oxide (IGZO), and low-temperature polycrystalline silicon (LTPS).
Various layers and portions of a frontplane, including electrodes, one or more organic layers, a pixel definition layer, and a capping layer may be deposited using any suitable deposition processes, including thermal evaporation and/or printing. It will be appreciated that, for example, a shadow mask may be used as appropriate to produce desired patterns when depositing such materials, and that various etching and selective deposition processes may also be used to pattern various layers. Examples of such methods include, but are not limited to, photolithography, printing (including ink or vapor jet printing and reel-to-reel printing), OVPD, and LITI patterning.
In one aspect, a method for selectively depositing a conductive coating over one or more emissive regions is provided. In some embodiments, the method includes depositing a first conductive coating on a substrate. The substrate may include a first emissive region and a second emissive region. The first conductive coating deposited on the substrate may include a first portion coating the first emissive region and a second portion coating the second emissive region of the substrate. The method may further include depositing a first nucleation inhibiting coating on the first portion of the first conductive coating, and then depositing a second conductive coating on the second portion of the first conductive coating.
As illustrated in
In stage 12, a first conductive coating 3131 is deposited over the substrate. As illustrated in
In stage 14, a first nucleation inhibiting coating 3141 is selectively deposited over a portion of the first conductive coating 3131. In the embodiment illustrated in
Once the first nucleation inhibiting coating 3141 has been deposited on a region of the surface of the first conductive coating 3131, a second conductive coating 3151 may be deposited on remaining uncovered region(s) of the surface where the nucleation inhibiting coating is not present. Turning to
In some embodiments, the method may further include additional stages following stage 16. Such additional stages may include, for example, depositing one or more additional nucleation inhibiting coatings, depositing one or more additional conductive coatings, depositing an auxiliary electrode, depositing an outcoupling coating, and/or encapsulation of the device.
It will be appreciated that, while the method has been illustrated and described above in relation to a device having the first and second emissive regions, it can similarly be applied to devices having three or more emissive regions. For example, such method may be used to deposit a conductive coating of varying thickness according to the emission spectrum of each of the emissive regions.
The first conductive coating 3131 and the second conductive coating 3151 may be light transmissive or substantially transparent in at least a portion of the visible wavelength range of the electromagnetic spectrum. For further clarity, the first conductive coating 3131 and the second conductive coating 3151 may each be light transmissive or substantially transparent in at least a portion of the visible wavelength range of the electromagnetic spectrum. Thus when the second conductive coating (and any additional conductive coating) is disposed on top of the first conductive coating to form a multi-coating electrode, such electrode may also be light transmissive or substantially transparent in the visible wavelength portion of the electromagnetic spectrum. For example, the light transmittance of the first conductive coating 3131, the second conductive coating 3151, and/or the multi-coating electrode may be greater than about 30%, greater than about 40%, greater than about 45%, greater than about 50%, greater than about 60%, greater than 70%, greater than about 75%, or greater than about 80% in a visible portion of the electromagnetic spectrum.
In some embodiments, the thickness of the first conductive coating 3131 and the second conductive coating 3151 may be made relatively thin to maintain a relatively high light transmittance. For example, the thickness of the first conductive coating 3131 may be about 5 to 30 nm, about 8 to 25 nm, or about 10 to 20 nm. The thickness of the second conductive coating 3151 may, for example, be about 1 to 25 nm, about 1 to 20 nm, about 1 to 15 nm, about 1 to 10 nm, or about 3 to 6 nm. Accordingly, the thickness of a multi-coating electrode formed by the combination of the first conductive coating 3131, the second conductive coating 3151 and any additional conductive coating may, for example, be about 6 to 35 nm, about 10 to 30 nm, or about 10 to 25 nm, or about 12 to 18 nm.
The first emissive region 3112 and the second emissive region 3114 may correspond to subpixel regions of an OLED display device in some embodiments.
Accordingly, it will be appreciated that the substrate 3102 onto which various coatings are deposited may include one or more additional organic and/or inorganic layers not specifically illustrated or described in the foregoing embodiments. For example, the OLED display device may be an active-matrix OLED (AMOLED) display device. In such embodiments, the substrate 3102 may comprise an electrode and at least one organic layer deposited over the electrode in each emissive region (e.g. subpixel), such that the first conductive coating 3131 may be deposited over the at least one organic layer. For example, the electrode may be an anode, and the first conductive coating 3131, either by itself or in combination with the second conductive coating 3151 and any additional conductive coatings, may form a cathode. The at least one organic layer may comprise an emitter layer. The at least one organic layer may further comprise a hole injection layer, a hole transport layer, an electron blocking layer, a hole blocking layer, an electron transport layer, an electron injection layer, and/or any additional layers. The substrate 3102 may further comprise a plurality of thin film transistors (TFTs). Each anode provided in the device may be electrically connected to at least one TFT. For example, the substrate 3102 may include one or more top-gate thin-film transistors (TFTs), one or more bottom-gate TFTs, and/or other TFT structures. A TFT may be a n-type TFT or a p-type TFT. Examples of TFT structures include those including amorphous silicon (a-Si), indium gallium zinc oxide (IGZO), and low-temperature polycrystalline silicon (LTPS).
The substrate 3102 may also include a base substrate for supporting the above-identified additional organic and/or inorganic layers. For example, the base substrate may be a flexible or rigid substrate. The base substrate may include, for example, silicon, glass, metal, polymer (e.g., polyimide), sapphire, or other materials suitable for use as the base substrate.
The first emissive region 3112 and the second emissive region 3114 may be subpixels configured to emit light of different wavelength or emission spectrum from one another. The first emissive region 3112 may be configured to emit light having a first wavelength or first emission spectrum, the second emissive region 3114 may be configured to emit light having a second wavelength or second emission spectrum. The first wavelength may be less than or greater than the second wavelength and/or the third wavelength, the second wavelength may be less than or greater than the first wavelength and/or the third wavelength. The device may comprise any number of additional emissive regions, pixels, or subpixels. For instance, the device may comprise additional emissive regions which are configured to emit light having a third wavelength or third emissive spectrum, which is different from the wavelength or emissive spectrum of the first emissive region or the second emissive region. The device may also comprise additional emissive regions which are configured to emit light having substantially identical wavelength or emissive spectrum as the first emissive region, the second emissive region, or other additional emissive regions.
In some embodiments, the first nucleation inhibiting coating 3141 may be selectively deposited using the same shadow mask used to deposit the at least one organic layer of the first emissive region 3112. In this way, the optical microcavity effect may be tuned for each subpixel in a cost-effective manner due to there being no additional mask requirements for depositing the nucleation inhibiting layers.
In the embodiment of
In the device 1300 illustrated in
In yet another embodiment illustrated in
In yet another embodiment illustrated in
The first conductive coating 1371, the second conductive coating 1372, and the third conductive coating 1373 may be light transmissive or substantially transparent in the visible wavelength portion of the electromagnetic spectrum. For further clarity, the first conductive coating 1371, the second conductive coating 1372, and the third conductive coating 1373 may each be light transmissive or substantially transparent at least in a portion of the visible wavelength range of the electromagnetic spectrum. Thus, when the second conductive coating and/or the third conductive coating are disposed on top of the first conductive coating to form the common cathode 1375, such electrode may also be light transmissive or substantially transparent in the visible wavelength portion of the electromagnetic spectrum. For example, the light transmittance of the first conductive coating 1371, the second conductive coating 1372, the third conductive coating 1373, and/or the common cathode 1375 may be greater than about 30%, greater than about 40%, greater than about 45%, greater than about 50%, greater than about 60%, greater than 70%, greater than about 75%, or greater than about 80% in a visible portion of the electromagnetic spectrum.
In some embodiments, the thickness of the first conductive coating 1371, the second conductive coating 1372, and the third conductive coating 1373 may be made relatively thin to maintain a relatively high light transmittance. For example, the thickness of the first conductive coating 1371 may be about 5 to 30 nm, about 8 to 25 nm, or about 10 to 20 nm. The thickness of the second conductive coating 1372 may, for example, be about 1 to 25 nm, about 1 to 20 nm, about 1 to 15 nm, about 1 to 10 nm, or about 3 to 6 nm. The thickness of the third conductive coating 1373 may, for example, be about 1 to 25 nm, about 1 to 20 nm, about 1 to 15 nm, about 1 to 10 nm, or about 3 to 6 nm. Accordingly, the thickness of a common cathode 1375 formed by the combination of the first conductive coating 1371 and the second conductive coating 1372 and/or the third conductive coating 1373 may, for example, be about 6 to 35 nm, about 10 to 30 nm, or about 10 to 25 nm, or about 12 to 18 nm.
The thickness of the auxiliary electrode 1381 may be greater than the thickness of the first conductive coating 1371, the second conductive coating 1372, the third conductive coating 1373, and/or the common cathode 1375. For example, the thickness of the auxiliary electrode 1381 may be greater than about 50 nm, greater than about 80 nm, greater than about 100 nm, greater than about 150 nm, greater than about 200 nm, greater than about 300 nm, greater than about 400 nm, greater than about 500 nm, greater than about 700 nm, greater than about 800 nm, greater than about 1 μm, greater than about 1.2 μm, greater than about 1.5 μm, greater than about 2 μm, greater than about 2.5 μm, or greater than about 3 μm. In some embodiments, the auxiliary electrode 1375 may be substantially non-transparent or opaque. However, since the auxiliary electrode 1375 is generally provided in the non-emissive region(s) of the device, the auxiliary electrode 1375 may not cause significant optical interference. For example, the light transmittance of the auxiliary electrode 1375 may be less than about 50%, less than about 70%, less than about 80%, less than about 85%, less than about 90%, or less than about 95% in the visible portion of the electromagnetic spectrum. In some embodiments, the auxiliary electrode 1375 may absorb light in at least a portion of the visible wavelength range of the electromagnetic spectrum.
The first conductive coating 1371 may comprise various materials commonly used to form light transmissive conductive layers or coatings. For example, the first conductive coating 1371 may include transparent conducting oxides (TCOs), metallic or non-metallic thin films, and any combination thereof. The first conductive coating 1371 may further comprise two or more layers or coatings. For example, such layers or coatings may be distinct layers or coatings disposed on top of one another. The first conductive coating 1371 may comprise various materials including, for example, indium tin oxide (ITO), fluorine tin oxide (FTO), indium zinc oxide (IZO), magnesium (Mg), aluminum (Al), ytterbium (Yb), silver (Ag), zinc (Zn), cadmium (Cd), and combinations of any two or more thereof, including alloys containing any of the foregoing materials. For example, the first conductive coating 1371 may comprise a Mg:Ag alloy, a Mg:Yb alloy, a bilayer structure including a Yb layer and an Ag layer, or a combination thereof. For a Mg:Ag alloy or a Mg:Yb alloy, the alloy composition may range from about 1:9 to about 9:1 by volume.
The second conductive coating 1372 and the third conductive coating 1373 may comprise high vapor pressure materials, such as ytterbium (Yb), zinc (Zn), cadmium (Cd) and magnesium (Mg). In some embodiments, the second conductive coating 1372 and the third conductive coating 1373 may comprise pure or substantially pure magnesium.
The auxiliary electrode 1381 may comprise substantially the same material(s) as the second conductive coating 1372 and/or the third conductive coating 1373. In some embodiments, the auxiliary electrode 1381 may include magnesium. For example, the auxiliary electrode 1381 may comprise pure or substantially pure magnesium. In other examples, the auxiliary electrode 1381 may comprise Yb, Cd, and/or Zn.
In some embodiments, the thickness of the nucleation inhibiting coating 1361, 1362, 1363 disposed in the emissive regions 1331a, 1331b, 1331c may be varied according to the color or emission spectrum of the light emitted by each emissive region. As illustrated in
By modulating the thickness of the nucleation inhibiting coating disposed in each emissive region or subpixel independently of one another, the optical microcavity effects in each emissive region or subpixel can be further controlled. For example, the thickness of the nucleation inhibiting coating disposed over a blue subpixel may be less than the thickness of the nucleation inhibiting coating disposed over a green subpixel, and the thickness of the nucleation inhibiting coating disposed over a green subpixel may be less than the thickness of the nucleation inhibiting coating disposed over a red subpixel. As would be appreciated, the optical microcavity effect in each emissive region or subpixel may be controlled to an even greater extent by modulating both the nucleation inhibiting coating thickness and the conductive coating thickness for each emissive region or subpixel independent of other emissive regions or subpixels.
Optical microcavity effects arise due to the presence of optical interfaces created by numerous thin-film layers and coatings with different refractive indices, which are used to construct opto-electronic devices such as OLEDs. Some factors which affect the optical microcavity effect observed in a device include the total path length (e.g. the total thickness of the device through which light emitted from the device travels before being out-coupled) and the refractive indices of various layers and coatings. It has now been found that, by modulating the thickness of the cathode in an emissive region (e.g. subpixel), the optical microcavity effect in the emissive region may be varied. Such effect may generally be attributed to the change in the total optical path length. It is further postulated that, particularly in the case of light-transmissive cathode formed by thin coating(s), the change in the cathode thickness may also change the refractive index of the cathode in addition to the total optical path length. Furthermore, the optical path length, and thus the optical microcavity effect, may also be modulated by changing the thickness of the nucleation inhibiting coating disposed in the emissive region.
The optical properties of the device which may be affected by modulating the optical microcavity effects include the emission spectrum, intensity (e.g. luminous intensity), and angular distribution of the output light, including the angular dependence of the brightness and color shift of the output light.
While various embodiments have been described with 2 or 3 emissive regions or subpixels, it will be appreciated that devices may comprise any number of emissive regions or subpixels. For example, a device may comprise a plurality of pixels, wherein each pixel comprises 2, 3, or more subpixels. Furthermore, the specific arrangement of the pixels or subpixels with respect to other pixels or subpixels may be varied depending on the device design. For example, the subpixels may be arranged according to known arrangement schemes such as RGB side-by-side, diamond, or PenTile®.
In one aspect, an opto-electronic device is provided. The opto-electronic device includes a first electrode and a second electrode, a semiconducting layer disposed between the first electrode and the second electrode, a nucleation inhibiting coating disposed over at least a portion of the second electrode, an auxiliary electrode, a patterning structure arranged to overlap with the auxiliary electrode to provide a shadowed region, and a conductive coating disposed in the shadowed region, the conductive coating in electrical connection with the auxiliary electrode and the second electrode.
While
In one aspect according to some embodiments, a device is provided. The device may be an opto-electronic device. In some embodiments, the device includes a substrate, a nucleation inhibiting coating, and an optical coating. The nucleation inhibiting coating covers a first region of the substrate. The optical coating covers a second region of the substrate, and at least a portion of the nucleation inhibiting coating is exposed from, or is substantially free of or is substantially uncovered by, the optical coating.
The optical coating may be used to modulate optical properties of light being transmitted, emitted, or absorbed by the device, including plasmon modes. For example, the optical coating may be used as an optical filter, index-matching coating, optical out-coupling coating, scattering layer, diffraction grating, or portions thereof. In another example, the optical coating may be used to modulate the microcavity effects in an opto-electronic device by tuning for example the total optical path length and/or the refractive index. The optical properties of the device which may be affected by modulating the optical microcavity effects include the emission spectrum, intensity (e.g. luminous intensity), and angular distribution of the output light, including the angular dependence of the brightness and color shift of the output light. In some embodiments, the optical coating may be a non-electrical component. In other words, the optical coating may not be configured to conduct or transmit electrical current during normal device operation in such embodiments.
For example, the optical coating may be formed using any of the various embodiments of methods for depositing the conductive coating described above. The optical coating may comprise high vapor pressure materials, such as ytterbium (Yb), zinc (Zn), cadmium (Cd) and magnesium (Mg). In some embodiments, the optical coating may comprise pure or substantially pure magnesium.
The formation of thin films during vapor deposition on a surface of a substrate involves processes of nucleation and growth. During initial stages of film formation, a sufficient number of vapor monomers (e.g., atoms or molecules) typically condense from a vapor phase to form initial nuclei on the surface. As vapor monomers continue to impinge upon the surface, a size and density of these initial nuclei increase to form small clusters or islands. After reaching a saturation island density, adjacent islands typically will start to coalesce, increasing an average island size, while decreasing an island density. Coalescence of adjacent islands continues until a substantially closed film is formed.
There can be three basic growth modes for the formation of thin films: 1) island (Volmer-Weber), 2) layer-by-layer (Frank-van der Merwe), and 3) Stranski-Krastanov. Island growth typically occurs when stable clusters of monomers nucleate on a surface and grow to form discrete islands. This growth mode occurs when the interactions between the monomers is stronger than that between the monomers and the surface.
The nucleation rate describes how many nuclei of a critical size form on a surface per unit time. During initial stages of film formation, it is unlikely that nuclei will grow from direct impingement of monomers on the surface, since the density of nuclei is low, and thus the nuclei cover a relatively small fraction of the surface (e.g., there are large gaps/spaces between neighboring nuclei). Therefore, the rate at which critical nuclei grow typically depends on the rate at which adsorbed monomers (e.g., adatoms) on the surface migrate and attach to nearby nuclei.
After adsorption of an adatom on a surface, the adatom may either desorb from the surface, or may migrate some distance on the surface before either desorbing, interacting with other adatoms to form a small cluster, or attach to a growing nucleus. An average amount of time that an adatom remains on the surface after initial adsorption is given by:
In the above equation, ν is a vibrational frequency of the adatom on the surface, k is the Boltzmann constant, T is temperature, and Edes is an energy involved to desorb the adatom from the surface. From this equation it is noted that the lower the value of Edes the easier it is for the adatom to desorb from the surface, and hence the shorter the time the adatom will remain on the surface. A mean distance an adatom can diffuse is given by,
where a0 is a lattice constant and ES is an activation energy for surface diffusion. For low values of Edes and/or high values of ES the adatom will diffuse a shorter distance before desorbing, and hence is less likely to attach to a growing nuclei or interact with another adatom or cluster of adatoms.
During initial stages of film formation, adsorbed adatoms may interact to form clusters, with a critical concentration of clusters per unit area being given by,
where Ei is an energy involved to dissociate a critical cluster containing i adatoms into separate adatoms, n0 is a total density of adsorption sites, and N1 is a monomer density given by:
N
1
={dot over (R)}τ
s
where {dot over (R)} is a vapor impingement rate. Typically i will depend on a crystal structure of a material being deposited and will determine the critical cluster size to form a stable nucleus.
A critical monomer supply rate for growing clusters is given by the rate of vapor impingement and an average area over which an adatom can diffuse before desorbing:
The critical nucleation rate is thus given by the combination of the above equations:
From the above equation it is noted that the critical nucleation rate will be suppressed for surfaces that have a low desorption energy for adsorbed adatoms, a high activation energy for diffusion of an adatom, are at high temperatures, or are subjected to low vapor impingement rates.
Sites of substrate heterogeneities, such as defects, ledges or step edges, may increase Edes, leading to a higher density of nuclei observed at such sites. Also, impurities or contamination on a surface may also increase Edes, leading to a higher density of nuclei. For vapor deposition processes conducted under high vacuum conditions, the type and density of contaminates on a surface is affected by a vacuum pressure and a composition of residual gases that make up that pressure.
Under high vacuum conditions, a flux of molecules that impinge on a surface (per cm2-sec) is given by:
where P is pressure, and M is molecular weight. Therefore, a higher partial pressure of a reactive gas, such as H2O, can lead to a higher density of contamination on a surface during vapor deposition, leading to an increase in Edes and hence a higher density of nuclei.
A useful parameter for characterizing nucleation and growth of thin films is the sticking probability given by:
where Nads is a number of adsorbed monomers that remain on a surface (e.g., are incorporated into a film) and Ntotal is a total number of impinging monomers on the surface. A sticking probability equal to 1 indicates that all monomers that impinge the surface are adsorbed and subsequently incorporated into a growing film. A sticking probability equal to 0 indicates that all monomers that impinge the surface are desorbed and subsequently no film is formed on the surface. A sticking probability of metals on various surfaces can be evaluated using various techniques of measuring the sticking probability, such as a dual quartz crystal microbalance (QCM) technique as described by Walker et al., J. Phys. Chem. C 2007, 111, 765 (2006).
As the density of islands increases (e.g., increasing average film thickness), a sticking probability may change. For example, a low initial sticking probability may increase with increasing average film thickness. This can be understood based on a difference in sticking probability between an area of a surface with no islands (bare substrate) and an area with a high density of islands. For example, a monomer that impinges a surface of an island may have a sticking probability close to 1.
An initial sticking probability S0 can therefore be specified as a sticking probability of a surface prior to the formation of any significant number of critical nuclei. One measure of an initial sticking probability can involve a sticking probability of a surface for a material during an initial stage of deposition of the material, where an average thickness of the deposited material across the surface is at or below threshold value. In the description of some embodiments, a threshold value for an initial sticking probability can be specified as 1 nm. An average sticking probability is then given by:
0(1−Anuc)+Snuc(Anuc)
where Snuc is a sticking probability of an area covered by islands, and Anuc is a percentage of an area of a substrate surface covered by islands.
An example of an energy profile of an adatom adsorbed onto a substrate surface is illustrated in
In (1), the local low energy site may be any site on the substrate surface onto which an adatom will be at a lower energy. Typically, the nucleation site may be a defect or anomaly on the surface substrate, such as for example, step edges, chemical impurities, bonding sites, or kinks. Once the adatom is trapped at the local low energy site, there is typically an energy barrier before surface diffusion can take place. This energy barrier is represented as ΔE in the diagram of
In (2), the adatom may diffuse on the substrate surface. For example, in the case of localized absorbates, adatoms tend to oscillate near the minima of the surface potential and migrate to various neighboring sites until the adatom is either desorbed, or is incorporated into a growing film or growing islands formed by a cluster of adatoms. In the diagram of
In (3), the activation energy associated with desorption of the adatom from the surface is represented as Edes. It will be appreciated that any adatoms that are not desorbed would remain on the substrate surface. For example, such adatoms may diffuse on the surface, be incorporated as part of a growing film or coating, or become part of a cluster of adatoms that form islands on the surface.
Based on energy profile shown in
While certain embodiments have been described above with reference to selectively depositing a conductive coating to form a cathode or an auxiliary electrode for a common cathode, it will be understood that similar materials and processes may be used to form an anode or an auxiliary electrode for an anode in other embodiments.
Suitable materials for use to form a nucleation inhibiting coating include those exhibiting or characterized as having an initial sticking probability for a material of a conductive coating of no greater than or less than about 0.1 (or 10%) or no greater than or less than about 0.05, and, more particularly, no greater than or less than about 0.03, no greater than or less than about 0.02, no greater than or less than about 0.01, no greater than or less than about 0.08, no greater than or less than about 0.005, no greater than or less than about 0.003, no greater than or less than about 0.001, no greater than or less than about 0.0008, no greater than or less than about 0.0005, or no greater than or less than about 0.0001. Suitable materials for use to form a nucleation promoting coating include those exhibiting or characterized as having an initial sticking probability for a material of a conductive coating of at least about 0.6 (or 60%), at least about 0.7, at least about 0.75, at least about 0.8, at least about 0.9, at least about 0.93, at least about 0.95, at least about 0.98, or at least about 0.99.
Suitable nucleation inhibiting materials include organic materials, such as small molecule organic materials and organic polymers. Examples of suitable organic materials include polycyclic aromatic compounds including organic molecules which may optionally include one or more heteroatoms, such as nitrogen (N), sulfur (S), oxygen (O), phosphorus (P), and aluminum (Al). In some embodiments, a polycyclic aromatic compound includes organic molecules each including a core moiety and at least one terminal moiety bonded to the core moiety. A number of terminal moieties may be 1 or more, 2 or more, 3 or more, or 4 or more. In the case of 2 or more terminal moieties, the terminal moieties may be the same or different, or a subset of the terminal moieties may be the same but different from at least one remaining terminal moiety.
In some embodiments, at least one terminal moiety is, or includes, a phenyl moiety represented by the structure (I-A) as follows:
In general, the phenyl moiety represented by (I-A) may be unsubstituted or substituted. In some embodiments, the phenyl moiety represented by (I-A) may be substituted by one or more substituent groups present as at least one of A1, A2, A3, A4, and A5, the one or more substituent groups independently selected from H, D (deutero), F, Cl, alkyl including C1-C6 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, and a combination of any two or more thereof. In some embodiments, the one or more substituent groups is independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl.
In some embodiments, at least one terminal moiety is, or includes, a naphthyl moiety represented by the structure (I-B) as follows:
wherein at least one of B1, B2, B3, B4, B5, B6, B7, and B8 represents a bond formed between the naphthyl moiety and the core moiety. In general, the naphthyl moiety represented by (I-B) may be unsubstituted or substituted. In some embodiments, the naphthyl moiety represented by (I-B) may be substituted by one or more substituent groups present as at least one of B1, B2, B3, B4, B5, B6, B7, and B8, the one or more substituent groups independently selected from: H, D (deutero), F, Cl, alkyl including C1-C6 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, and a combination of any two or more thereof. In some embodiments, the one or more substituent groups is independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl. In some embodiments, the “B” substituent is a corresponding B′ (B-prime) substituent and any B′ substituent may have the value of the indicated B substituent herein.
In some embodiments, at least one terminal moiety is, or includes, a phenanthrenyl moiety represented by the structure (I-C) as follows:
wherein at least one of C1, C2, C3, C4, C5, C6, C7, C8, C9, and C10 represents a bond formed between the phenanthryl moiety and the core moiety. In general, the phenanthryl moiety represented by (I-C) may be unsubstituted or substituted. In some embodiments, the phenanthryl moiety represented by (I-C) may be substituted by one or more substituent groups present as at least one of C1, C2, C3, C4, C5, C6, C7, C8, C9, and C10, the one or more substituent groups independently selected from: H, D (deutero), F, Cl, alkyl including C1-C6 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, and a combination of any two or more thereof. In some embodiments, the one or more substituent groups is independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl. In some embodiments, the “C” substituent is a corresponding C′ (C-prime) substituent and any C′ substituent may have the value of the indicated C substituent herein.
In some embodiments, at least one terminal moiety is, or includes, an anthracenyl moiety represented by the structure (I-D) as follows:
wherein at least one of the D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10 represents a bond formed between the phenanthryl moiety and the core moiety. In general, the anthracenyl moiety represented by (I-D) may be unsubstituted or substituted. In some embodiments, the anthracenyl moiety represented by (I-D) may be substituted by one or more substituent groups present as at least one of D1, D2, D3, D4, D5, D6, D7, D8, D9, and D10, the one or more substituent groups independently selected from: H, D (deutero), F, Cl, alkyl including C1-C6 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, and a combination of any two or more thereof. In some embodiments, the one or more substituent groups is independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl.
In some embodiments, at least one terminal moiety is, or includes, a benzanthracenyl moiety represented by the structure (I-E) as follows:
wherein at least one of the E1, E2, E3, E4, E5, E6, E7, E8, E9, E10, E11, and E12 represents a bond formed between the benzanthracenyl moiety and the core moiety. In general, the benzanthracenyl moiety represented by (I-E) may be unsubstituted or substituted. In some embodiments, the benzanthracenyl moiety represented by (I-E) may be substituted by one or more substituent groups present as at least one of E1, E2, E3, E4, E5, E6, E7, E8, E9, E10, E11, and E12, the one or more substituent groups independently selected from: H, D (deutero), F, C1, alkyl including C1-C6 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, and a combination of any two or more thereof. In some embodiments, the one or more substituent groups is independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl.
In some embodiments, at least one terminal moiety is, or includes, a pyrenyl moiety represented by the structure (I-F) as follows:
wherein at least one of the F1, F2, F3, F4, F5, F6, F7, F8, F9, and F10 represents a bond formed between the pyrenyl moiety and the core moiety. In general, the pyrenyl moiety represented by (I-F) may be unsubstituted or substituted. In some embodiments, the pyrenyl moiety represented by (I-F) may be substituted by one or more substituent groups present as at least one of F1, F2, F3, F4, F5, F6, F7, F8, F9, and F10, the one or more substituent groups independently selected from: H, D (deutero), F, Cl, alkyl including C1-C6 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, and a combination of any two or more thereof. In some embodiments, the one or more substituent groups is independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl.
In some embodiments, at least one terminal moiety is, or includes, a chrysenyl moiety represented by the structure (I-G) as follows:
wherein at least one of G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, and G12 represents a bond formed between the chrysenyl moiety and the core moiety. In general, the chrysenyl moiety represented by (I-G) may be unsubstituted or substituted. In some embodiments, the chrysenyl moiety represented by (I-G) may be substituted by one or more substituent groups present as at least one of G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, and G12, the one or more substituent groups independently selected from: H, D (deutero), F, Cl, alkyl including C1-C6 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, a combination of any two or more thereof. In some embodiments, the one or more substituent groups is independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl.
In yet another embodiment, at least one terminal moiety is, or includes, a polycyclic aromatic moiety including fused ring structures, such as fluorene moieties or phenylene moieties (including those containing multiple (e.g., 3, 4, or more) fused benzene rings). Examples of such moieties include spirobifluorene moiety, triphenylene moiety, diphenylfluorene moiety, dimethylfluorene moiety, difluorofluorene moiety, and combinations of any two or more thereof.
In some embodiments, a polycyclic aromatic compound includes organic molecules each including a core moiety and at least one terminal moiety bonded to the core moiety, wherein the core moiety is, or includes, an anthracenyl moiety represented by structure (II) as follows:
In (II), one or more terminal moieties are bonded to the anthracenyl core moiety. For example, 1, 2, 3, 4, or more terminal moieties may be bonded directly or indirectly (e.g. via a linker moiety) to the anthracenyl core moiety. In some embodiments, 2 independently selected terminal moieties are bonded to the anthracenyl core moiety. For example, one or more terminal moieties may be independently bonded to one or more of 1-, 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-, and 10-positions indicated in (II) above. In some embodiments, 2 independently selected terminal moieties are bonded to the anthracenyl core moiety in the 9- and 10-positions. In some further embodiments, a third independently selected terminal moiety is bonded to the anthracenyl core moiety. For example, the third independently selected terminal moiety may be bonded to the anthracenyl core moiety in the 2-, 3-, 6-, or 7-positions. In a yet further embodiment, a fourth independently selected terminal moiety is bonded to the anthracenyl core moiety in an unoccupied position selected from the 2-, 3-, 6-, and 7-positions.
The one or more terminal moieties bonded to the anthracenyl core moiety in (II) is, or includes, a moiety represented by (I-A), (I-B), or (I-C), (I-D), (I-E), (I-F), (I-G) or a polycyclic aromatic moiety including fused ring structures as described above. The one or more terminal moiety may be directly bonded to the core moiety, or may be bonded to the core moiety via a linker moiety. Examples of a linker moiety include —O— (where θ denotes an oxygen atom), —S— (where S denotes a sulfur atom), and cyclic or acyclic hydrocarbon moieties including 1, 2, 3, 4, or more carbon atoms, and which may be unsubstituted or substituted, and which may optionally include one or more heteroatoms. The bond between the core moiety and one or more terminal moieties may be a covalent bond, for example. In embodiments wherein two or more terminal moieties are bonded to the core moiety, each of the two or more terminal moieties may be selected independent of one another. For example, the two or more terminal moieties may be the same or different as one another. In one embodiment, a polycyclic aromatic compound includes organic molecules each including an anthracenyl core moiety represented by (II). The organic molecules each includes a first terminal moiety in the form of a phenyl moiety represented by (I-A), and a second terminal moiety in the form of a naphthyl moiety represented by (I-B), a phenanthryl moiety represented by (I-C), an anthracenyl moiety represented by (I-D), a benzanthracenyl moiety represented by (I-E), a pyrenyl moiety represented by (I-F) or a chrysenyl moiety represented by (I-G). For example, the first terminal moiety may be bonded to the 1-, 9-, or 8-position, and the second terminal moiety may be bonded to the 4-, 10-, or 5-position. The first terminal moiety and the second terminal moiety may be symmetrically or asymmetrically arranged with respect to one another about the anthracenyl core moiety. For example, the first terminal moiety and the second terminal moiety may be symmetrically arranged by bonding the first terminal moiety and the second terminal moiety to the 1-position and the 4-position, the 9-position and the 10-position, or the 8-position and the 5-position, respectively. In another example, the first terminal moiety and the second terminal moiety may be asymmetrically arranged by bonding the first terminal moiety and the second terminal moiety to the 1-position and the 5-position, or the 8-position and the 4-position, respectively. In some embodiments, one or more additional terminal moieties may be bonded to the anthracenyl core moiety. The one or more additional terminal moieties may each be bonded to one or more unoccupied positions of the anthracenyl core moiety. For example, the one or more additional terminal moieties may be each be bonded to the 2-, 3-, 6-, or 7-position.
In some embodiments, one or more carbon atoms of the polycylic aromatic compound may be substituted by a heteroatom. For example, one or more carbon atoms in a terminal moiety and/or the core moiety may be substituted by a heteroatom. Examples of such heteroatom substitutions include, but are not limited to, sulfur and nitrogen.
In some embodiments, the polycyclic aromatic compound contains at least one fluorine (F) atom.
Examples of polycyclic aromatic compounds containing an anthracenyl core are provided below.
In the moiety represented by structures A1 to A66, X1 to X10 represents the presence of one or more substituent groups. For example, one or more substituent groups, X1 to X10, may independently be selected from: H, D (deutero), F, Cl, alkyl including C1-C4 alkyl, cycloalkyl, silyl, fluoroalkyl, arylalkyl, aryl, heteroaryl, alkoxy, fluoroalkoxy, and combinations of any two or more thereof. Furthermore, one or more substituent groups, may be independently selected from: methyl, methoxy, ethyl, t-butyl, fluoromethyl, difluoromethyl, trifluoromethyl, trifluoromethoxy, fluoroethyl, and polyfluoroethyl. Descriptions of other substituent groups, A1, A2, A3, A4, A5, B1, B2, B3, B4, B5, B6, B7 (as well as the B′ counterparts to B1-B7), C1, C2, C3, C4, C5, C6, C7, C8, C9 (as well as the C′ counterparts to C1-C9), D1, D2, D3, D4, D5, D6, D7, D8, D9, E1, E2, E3, E4, E5, E6, E7, E8, E9, E10, E11, F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, G1, G2, G3, G4, G5, G6, G7, G8, G9, G10, G11, and G12, provided above in relation to (I-A), (I-B), or (I-C), (I-D), (I-E), (I-F), (I-G) are applicable to the corresponding substituent groups represented by A1 to A66.
Examples of alkyl substituent includes C1-C6 alkyl, which may be straight or branched. For example, in the case of C4-C6 alkyl, branched alkyl may be preferred in some cases.
In one example wherein the moiety is represented by structure A1, at least one of B1, B2, B3, B5, B6, B7, B8, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5, and A6 is F. In a further example, at least one of B1, B2, B3, B5, B6, B7, B8, X2, X3, X6 X7, A2, A3, A4, A5 and A6 is F. In a yet further example, at least one of B1, B2, B6, B7, B8, X2, X3, X6, X7, A2, A3, A4, A5, and A6 is F. In a yet further example, at least one of B1, B2, B6, B7, B8, X2, X3, X6, X7, A3, A4, and A5 is F. In a yet further example, at least one of B1, B2, B6, B7, B8, X2, X3, X6, X7, A2, and A6 is F. For example, up to 10, 6, 5, 3, or 1 F atoms may be present in such structure.
In another example wherein the moiety is represented by structure A1, at least one of B1, B2, B3, B5, B6, B7, B8, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5, and A6 is alkyl. In a further example, at least one of B1, B2, B3, B5, B6, B7, B8, X1, X2, X3, X6, X7, X8, A2, A3, A4, A5, and A6 is alkyl. In a yet further example, at least one of B1, B2, B6, B7, B8, X1, X2, X3, X6 X7, X8, A3, A4, and A5 is alkyl. In a yet further example, at least one of A3, A4, and A5 is alkyl. For example, up to 6, 5, 3, or 1 alkyl substituent may be present in such structure.
In another example wherein the moiety is represented by structure A1, at least one of B1, B2, B3, B5, B6, B7, B8, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of B1, B2, B3, B5, B6, B7, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In further example, at least one of B1, B2, B6, B7, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of A3, A4 and A5 is fluoroalkyl or fluoroalkoxy. For example, up to 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A1, at least one of B1, B2, B3, B5, B6, B7, B8, X2, X3, X6 X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl, or heteroaryl. In further example, at least one of B2, B3, B6, B7, B8, X2, X3, X6 X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl, or heteroaryl. In a further example, at least one of B2, B3, B5, X2, X3, X6 X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl, or heteroaryl. In a further example, at least one of B2, B3, B5, X2, X3, X6, X7, A2, A3, A5 and A6 is aryl, arylalkyl, or heteroaryl. In a further example, at least one of B2, B3, B5, X2, X3, X6, X7, A5 and A6 is aryl, arylalkyl, or heteroaryl. For example, up to 8, 6, 4, 3, or 1 such substituent may be present in such structure.
In one example wherein the moiety is represented by structure A2, at least one of B1, B2, B4, B5, B6, B7, B8, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5 and A6 is F. In a further example, at least one of B1, B2, B4, B5, B6, B7, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is F. In a further example, at least one of B1, B5, B6, B7, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is F. In a further example, at least one of B1, B5, B6, B7, B8, X2, X3, X6, X7, A3, A4 and A5 is F. For example, up to 10, 6, 5, 3, or 1 F atom may be present in such structure.
In another example wherein the moiety is represented by structure A2, at least one of B1, B2, B4, B5, B6, B7, B8, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5 and A6 is alkyl. In a further example, at least one of B1, B2, B4, B5, B6, B7, B8, X1, X2, X3, X6, X7, X8, A2, A3, A4, A5 and A6 is alkyl. In a further example, at least one of B1, B5, B6, B7, B8, X1, X2, X3, X6, X7, X8, A2, A3, A4, A5 and A6 is alkyl. In a further example, at least one of A3, A4 and A5 is alkyl. For example, up to 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A2, at least one of B1, B2, B4, B5, B6, B7, B8, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of B1, B2, B4, B5, B6, B7, B8, X2, X3 X6, X7, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of B1, B5, B6, B7, B8, X2, X3 X6, X7, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of B1, B5, B6, B7, B8, X2, X3 X6, X7, A3, A4 and A5 is fluoroalkyl or fluoroalkoxy. For example, up to 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A2, at least one of B1, B2, B4, B5, B6, B7, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl or heteroaryl. In a further example, at least one of B1, B5, B6, B7, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl or heteroaryl. In a further example, at least one of B5, B6, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl or heteroaryl. In a further example, at least one of B5, B6, B8, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl or heteroaryl. For example, up to 8, 6, 4, 3, or 1 such substituent may be present in such structure.
In one example wherein the moiety is represented by structure A3, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5 and A6 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is F. In a further example, at least one of A3, A4 and A5 is F. For example, up to 12, 10, 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A3, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5 and A6 is alkyl or alkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X6, X7, X8, A2, A3, A4, A5 and A6 is alkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is alkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, A3, A4 and A5 is alkyl. For example, up to 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A3, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of A3, A4 and A5 is fluoroalkyl or fluoroalkoxy. For example, up to 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A3, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, A2, A3, A4, A5 and A6 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, A2 and A6 is aryl, arylalkyl or heteroaryl. For example, up to 8, 6, 4, 3, or 1 such substituent may be present in such structure.
In one example wherein the moiety is represented by structure A4, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, B1, B2, B4, B5, B6, B7 and B8 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, B1, B2, B4, B5, B6, B7 and B8 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6 X7, B1, B2, B4, B5, B6, B7 and B8 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, B1, B5, B6, B7 and B8 is F. For example, up to 14, 10, 8, 6, 4, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A4, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, B1, B2, B4, B5, B6, B7 and B8 is alkyl or fluoroalkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X6, X7, X8, B1, B2, B4, B5, B6, B7 and B8 is alkyl or fluoroalkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X1, X2, X3, X6, X7, X8, B1, B2, B4, B5, B6, B7, and B8 is alkyl or fluoroalkyl. In a further example, at least one of B1, B5, B6, B7 and B8 is alkyl or fluoroalkyl. For example, up to 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A4, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, B1, B2, B4, B5, B6, B7 and B8 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6 X7, B1, B2, B4, B5, B6, B7 and B8 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C4, C5, C6, C7, X2, X3, X6, X7, B1, B2, B4, B5, B6, B7, and B8 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C4, C5, C6, C7, X2, X3, X6, X7, B2, and B4 is aryl, arylalkyl or heteroaryl. For example, up to 8, 6, 4, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A4, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, B1, B2, B4, B5, B6, B7 and B8 is fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, B1, B2, B4, B5, B6, B7 and B8 is fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6 X7, B1, B2, B4, B5, B6, B7 and B8 is fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, B1, B5, B6, B7 and B8 is fluoroalkoxy. For example, up to 7, 5, 3, or 1 such substituent may be present in such structure.
In one example wherein the moiety is represented by structure A5, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, B1, B2, B3, B5, B6, B7 and B8 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, B1, B2, B3, B5, B6, B7 and B8 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6 X7, B1, B2, B3, B5, B6, B7 and B8 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, B1, B2, B6, B7 and B8 is F. In a further example, at least one of B1, B2, B7 and B8 is F. For example, up to 16, 10, 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A5, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, B1, B2, B3, B5, B6, B7 and B8 is alkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X6, X7, X8, B1, B2, B3, B5, B6, B7 and B8 is alkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, B1, B2, B6, B7 and B8 is alkyl. In a further example, at least one of C1, C2, C3, C6, C7, B1, B2, B7 and B8 is alkyl. For example, up to 10, 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A5, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, B1, B2, B3, B5, B6, B7 and B8 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6 X7, B1, B2, B3, B5, B6, B7 and B8 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, B1, B2, B3, B5, B6, B7 and B8 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, B1, B2, B6, B7 and B8 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of B1, B2, B7 and B8 is fluoroalkyl or fluoroalkoxy. For example, up to 8, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A5, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, B1, B2, B3, B5, B6, B7 and B8 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, B1, B2, B3, B5, B6, B7 and B8 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C4, C5, C6, C7, X2, X3, X6, X7, B1, B2, B3, B6, B7 and B8 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C4, C5, C6, C7, X2, X3, X6, X7, B3 and B6 is aryl, arylalkyl or heteroaryl. For example, up to 8, 6, 4, 3, or 1 such substituent may be present in such structure.
In one example wherein the moiety is represented by structure A6, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is F. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′6, C′8, and C′10 is F. In a further, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is F. In a further example, at least one of C3, C4, C5, C6, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is F. In a further example, at least one of C3, C4, C5, C6, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6 and C′7 is F. For example, up to 18, 12, 10, 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A6, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is alkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X6, X7, X8, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is alkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X1, X2, X3, X6, X7, X8, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is alkyl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X1, X2, X3, X6, X7, X8, C′1, C′2, C′3, C′4, C′6 and C′7 is alkyl. For example, up to 8, 6, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A6, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X1, X2, X3, X4, X5, X6, X7, X8, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C3, C4, C5, C6, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is fluoroalkyl or fluoroalkoxy. In a further example, at least one of C3, C4, C5, C6, X2, X3, X6, X7, C′1, C′3, C′4, C′5, C′6, and C′7 is fluoroalkyl or fluoroalkoxy. For example, up to 8, 5, 3, or 1 such substituent may be present in such structure.
In another example wherein the moiety is represented by structure A6, at least one of C1, C2, C3, C4, C5, C6, C7, C8, C10, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C3, C4, C5, C6, C7, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C4, C5, C6, C7, X2, X3, X6, X7, C′1, C′2, C′3, C′4, C′5, C′6, C′7, C′8, and C′10 is aryl, arylalkyl or heteroaryl. In a further example, at least one of C1, C2, C4, C5, C6, C7, X2, X3, X6, X7, C′8, and C′10 is aryl, arylalkyl or heteroaryl. For example, up to 8, 6, 4, 3, or 1 such substituent may be present in such structure.
Without wishing to be bound by any particular theory, it is generally postulated that molecules with one or more of the following characteristics may be particularly suitable for use in forming the nucleation inhibiting coating: (i) relatively low degree of symmetry in molecular structure; (ii) containing bonds with a relatively high rotational energy barrier; (iii) relatively large optical gap; and (iv) relatively low likelihood of reacting with the material for forming the conductive coating. For example, it is postulated that, for molecular structures containing a naphthyl terminal moiety, it may generally be preferable for such naphthyl moiety to be bonded directly or indirectly to the core moiety at the 1- or 4-position, rather than at 2- or 3-position. Such configuration may contribute to increasing the rotational energy barrier of the naphthyl terminal moiety. In another example, it is postulated that, for molecular structures containing a phenanthrenyl moiety, it may generally be preferable for such phenanthrenyl moiety to be bonded directly or indirectly to the core moiety at the 9-, or 10-position over the 1- or 3-position, which is still preferable over bonding at the 2- or 7-position for increasing the rotational energy barrier of the phenathrenyl moiety. In some embodiments, the nucleation inhibiting coating includes a molecule exhibiting an optical gap of greater than about 2.5 eV, greater than about 2.6 eV, greater than about 2.7 eV, or greater than about 2.8 eV. Generally, molecules with greater optical gap decrease the absorption of light in the visible portion of the electromagnetic spectrum and thus may be preferable in at least some applications.
In some embodiments, the polycyclic aromatic compound contains one or more fluorine atoms. For example, the polycyclic aromatic compound may contain 1, 2, 3, 4 or more fluorine atoms. In some embodiments, the polycyclic aromatic compound contains between 1 and 3 fluorine atoms. Further examples of polycyclic aromatic compounds containing an anthracenyl core are provided below.
Suitable nucleation inhibiting materials include polymeric materials. Examples of such polymeric materials include: fluoropolymers, including but not limited to perfluorinated polymers and polytetrafluoroethylene (PTFE); polyvinylbiphenyl; polyvinylcarbazole (PVK); and polymers formed by polymerizing a plurality of the polycyclic aromatic compounds as described above. In another example, polymeric materials include polymers formed by polymerizing a plurality of monomers, wherein at least one of the monomers includes a terminal moiety that is, or includes, a moiety represented by (I-A), (I-B), or (I-C), (I-E), (I-F), (I-G) or a polycyclic aromatic moiety including fused ring structures as described above.
Aspects of some embodiments will now be illustrated and described with reference to the following examples, which are not intended to limit the scope of the present disclosure in any way.
Synthesis of Compound 1 (“SF13”): 9-(naphthalen-1-yl)-10-phenylanthracene. The following reagents were mixed in a 500 mL reaction vessel: 9-bromo-10-(naphthalene-1-yl)anthracene (1.500 g, 3.91 mmol); tetrakis(triphenylphosphine)palladium(0) (Pd(PPh3)4, 0.678 g, 0.587 mmol); potassium carbonate (K2CO3, 1.623 g, 11.7 mmol); and 0.0782 mol of a boronic acid. In the present example, phenylboronic acid (0.954 g) was used as the boronic acid. The reaction vessel containing the mixture was placed on a heating plate mantle and stirred using a magnetic stirrer. The reaction vessel was also connected to a water condenser. A well stirred 300 ml solvent mixture containing a 20:5:3 volumetric ratio of toluene, ethanol and water, was prepared separately in a round-bottom flask. The flask containing the solvent mixture was sealed and degassed using N2 for a minimum of 30 minutes before a cannula was used to transfer the solvent mixture from the round-bottom flask to the reaction vessel without exposure to air. Once all of the solvent mixture was transferred, the reaction vessel was purged with nitrogen, and heated to a temperature of 65° C. while stirring at around 1200 RPM and left to react for at least 12 hours under a nitrogen environment. Once the reaction was determined to be complete, the mixture was cooled to room temperature before the solvent mixture was removed using a vacuum rotary evaporator. The contents of the flask were then re-dissolved in dichloromethane (DCM), and washed four times with a 500 mL of 1M NaOH solution, followed by washing twice with 500 mL of water. The organic phase was washed over magnesium sulfate and filtered. The resulting product was purified by passing twice through a silica gel plug column under vacuum suction. The DCM solvent was removed to produce the product in a powdered form. The powdered product was then further purified using train sublimation under reduced pressure of 20-50 mTorr and using CO2 as a carrier gas. Yield after purification using the silica gel plug column was 0.940 g (31.5%). The yield of the sublimation step was approximately 74%. 1H NMR (600 MHz, CD2Cl2) δ 8.14 (ddd, J=8.3, 3.3, 0.9 Hz, 1H), 8.11-8.04 (m, 1H), 7.81-7.59 (m, 7H), 7.59-7.51 (m, 2H), 7.52-7.41 (m, 2H), 7.41-7.31 (m, 2H), 7.33-7.20 (m, 3H), 7.15 (dt, J=8.5, 1.0 Hz, 1H). λAbs=376.1 nm (DCM)
Synthesis of Compound 2 (“SF360”): 9-(naphthalen-1-yl)-10-4-tolyphenylanthracene. Compound 2 was synthesized using an identical procedure to Compound 1 as described above, with the exception of 4-tolylphenylboronic acid (1.064 g) being used as the boronic acid reactant. Yield after purification using the silica gel plug column was 1.176 g (38.0%). The yield of the sublimation step was approximately 81%. 1H NMR (400 MHz, CD2Cl2) δ 8.09 (d, J=8.3 Hz, 1H), 8.04 (d, J=8.2 Hz, 1H), 7.81-7.68 (m, 3H), 7.57 (dd, J=7.0, 1.3 Hz, 1H), 7.52-7.42 (m, 4H), 7.26-7.17 (m, 3H), 2.55 (s, 3H). λAbs=376.6 nm (DCM), λfluo=nm (Toluene).
Synthesis of Compound 3 (“SF361”): 9-(naphthalen-1-yl)-10-4-fluorophenylanthracene. Compound 3 was synthesized using an identical procedure to Compound 1 as described above, with the exception of 4-fluorophenylboronic acid (1.095 g) being used as the boronic acid reactant. Yield after purification using the silica gel plug column was 1.064 g (34.1%). The yield of the sublimation step was approximately 74%. 1H NMR (600 MHz, CD2Cl2) δ 8.14 (dt, J=8.3, 1.1 Hz, 1H), 8.08 (dt, J=8.3, 0.9 Hz, 1H), 7.80-7.73 (m, 3H), 7.63-7.56 (m, 2H), 7.56-7.51 (m, 2H), 7.45 (ddd, J=8.8, 1.3, 0.8 Hz, 2H), 7.43-7.36 (m, 4H), 7.27 (dddd, J=8.0, 6.3, 5.0, 1.3 Hz, 3H), 7.15-7.12 (m, 1H). λabs=375.6 nm (DCM).
Synthesis of Compound 4 (“SF359”): 9-(naphthalen-1-yl)-10-4-trifluoromethylphenylanthracene. Compound 4 was synthesized using an identical procedure to Compound 1 as described above, with the exception of 4-trifluoromethylphenylboronic acid (1.487 g) being used as the boronic acid reactant. Yield after purification using the silica gel plug column was 0.899 g (25.6%). The yield of the sublimation step was approximately 74%. 1H NMR (600 MHz, CD2Cl2) δ 8.15 (dd, J=8.3, 1.1 Hz, 1H), 8.09 (dt, J=8.4, 0.9 Hz, 1H), 8.02-7.91 (m, 2H), 7.83-7.74 (m, 2H), 7.74-7.66 (m, 3H), 7.62 (dd, J=6.8, 1.2 Hz, 1H), 7.55 (ddd, J=8.1, 6.6, 1.2 Hz, 1H), 7.47 (dt, J=8.9, 1.0 Hz, 2H), 7.39 (ddd, J=8.9, 6.4, 1.3 Hz, 2H), 7.32-7.22 (m, 3H), 7.14 (dd, J=8.5, 1.1 Hz, 1H). λabs=375.3 nm (DCM).
Synthesis of Compound 5 (“SF16”): 9-(naphthalen-1-yl)-10-4-methoxyphenylanthracene. Compound 5 was synthesized using an identical procedure to Compound 1 as described above, with the exception of 4-methoxyphenylboronic acid (1.189 g) being used as the boronic acid reactant. Yield after purification using the silica gel plug column was 1.387 g (43.2%). The yield of the sublimation step was approximately 74%. 1H NMR (600 MHz, CD2Cl2) δ 8.14 (dt, J=8.3, 1.1 Hz, 1H), 7.85-7.67 (m, 4H), 7.63-7.53 (m, 2H), 7.52 (d, J=1.4 Hz, 1H), 7.52-7.44 (m, 3H), 7.44-7.41 (m, 1H), 7.37 (ddd, J=8.9, 6.4, 1.3 Hz, 2H), 7.30-7.18 (m, 6H), 7.16-7.08 (m, 2H), 4.01 (s, 3H). λabs=377.4 nm (DCM).
Synthesis of Compound 6 (“SF358”): 9-(3-Trifluoromethylphenyl)-10-(naphthalene-1-yl)anthracene. Compound 6 was synthesized using an identical procedure to Compound 1 as described above, with the exception of 3-Trifluoromethylphenylboronic acid (1.49 g) being used as the boronic acid reactant. Yield after purification using the silica gel plug column was 1.14 g. The yield of the sublimation step was approximately 79%. GC/MS elution time 5.53 min with an abundance of 1.1×106. 1H NMR (400 MHz, CDCl3) δ 8.06 (d, J=8.2 Hz, 1H), 8.01 (d, J=8.3 Hz, 1H), 7.86-7.67 (m, 5H), 7.61 (d, J=8.8 Hz, 2H), 7.55 (d, J=6.3 Hz, 1H), 7.52-7.41 (m, 3H), 7.37-7.30 (m, 2H), 7.27-7.18 (m, 3H), 7.13 (t, J=7.6 Hz, 1H). λAbs=397 nm (DCM), λfluo=411 nm (DCM).
Synthesis of Compound 7 (“SF4”): 9-(3,4,5-Trifluorophenyl)-10-(naphthalene-1-yl)anthracene. Compound 7 was synthesized using an identical procedure to Compound 1 as described above, with the exception of 3,4,5-Trifluorophenylboronic acid (1.38 g) being used as the boronic acid reactant. Yield after purification using the silica gel plug column was 1.01 g. The yield of the sublimation step was approximately 82%. GC/MS elution time 5.707 min with an abundance of 5.0×106. 1H NMR (400 MHz, CDCl3) δ 8.06 (d, J=8.3 Hz, 1H), 8.01 (d, J=8.2 Hz, 1H), 7.73-7.61 (m, 3H), 7.56-7.32 (m, 5H), 7.27-7.06 (m, 5H). λAbs=396 nm (DCM), Xfluo=430 nm (DCM).
Synthesis of Compound 8 (“SF25”): 9-(2-Fluorophenyl)-10-(naphthalene-1-yl) anthracene. Compound 8 was synthesized using an identical procedure to Compound 1 as described above, with the exception of 2-fluorophenylboronic acid (1.10 g) being used as the boronic acid reactant. Yield after purification using the silica gel plug column was 1.32 g. The yield of the sublimation step was approximately 81%. GC/MS elution time 6.475 min with an abundance of 8.4×106. 1H NMR (400 MHz, CDCl3) δ 8.06 (d, J=8.1 Hz, 1H), 8.00 (d, J=8.2 Hz, 1H), 7.68 (d, J=9.0 Hz, 3H), 7.46 (dddd, J=60.9, 29.3, 13.0, 7.7 Hz, 10H), 7.25-7.11 (m, 4H). λAbs=397 nm (DCM), λfluo=407 nm (DCM).
Synthesis of Compound 9 (“SF316”): 9-(4-Trifluoromethylphenyl)-10-(naphthalene-2-yl)anthracene. The following reagents were mixed in a 1 L reaction vessel: 9-bromo-10-(naphthalene-2-yl)anthracene (0.853 g, 2.23 mmol); Tetrakis(triphenylphosphine)palladium (Pd(PPh3)4, 0.385 g, 15 mol %); potassium carbonate (K2CO3, 0.923 g, 6.69 mmol); and 4.46 mmol of a boronic acid. In the present example, 4-Trifluoromethylphenylboronic acid (0.845 g) was used as the boronic acid. The reaction vessel containing the mixture was placed on a heating plate mantle and stirred using a magnetic stirrer. The reaction vessel was also connected to a water condenser. A well stirred 191 ml solvent mixture containing a 6.6:3.3:1 volumetric ratio of toluene, ethanol and water, was prepared separately in a round-bottom flask. The flask containing the solvent mixture was sealed and degassed using N2 for a minimum of 30 minutes before a cannula was used to transfer the solvent mixture from the round-bottom flask to the reaction vessel without exposure to air. Once all of the solvent mixture was transferred, the reaction vessel was purged with nitrogen, and heated to a temperature of 65° C. while stirring at around 1200 RPM and left to react for at least 12 hours under a nitrogen environment. Once the reaction was determined to be complete, the mixture was cooled to room temperature before the solvent mixture was removed using a vacuum rotary evaporator. The contents of the flask were then re-dissolved in dichloromethane (DCM), and washed with 1M NaOH solution, followed by washing with water. The organic phase was washed over magnesium sulfate and filtered. The resulting product was purified by passing through a silica gel plug column under vacuum suction. The DCM solvent was removed to produce the product in a powdered form. The powdered product was then further purified using train sublimation under reduced pressure of 20-50 mTorr and using CO2 as a carrier gas. 1H NMR (CDCl3): 8.09 (d, J=8.58 Hz, 1H), 8.04 (m, 1H), 7.98 (s, 1H), 7.91 (m, 1H), 7.74 (m, 2H), 7.63 (m, 7H), 7.35 (m, 4H). 19F NMR (CDCl3): 62.32 (s). λAbs=397 nm (DCM), λfluo=423 nm (DCM). Yield (purified)=61%, Yield (sublimed)=88%. MS (m/z, %): 436.3 (M+, 100) GC retention time=7.30 minutes.
Synthesis of Compound 10 (“SF317”): 9-(3,4,5-Trifluorophenyl)-10-(naphthalene-2-yl)anthracene. Compound 10 was synthesized using an identical procedure to Compound 9 as described above, with the exception of 3,4,5-Trifluorophenlylboronic acid (0.809 g, 4.60 mmol) being used as the boronic acid reactant, and being combined with: 9-bromo-10-(naphthalene-2-yl)anthracene (0.882 g, 2.30 mmol), 3,4,5-trifluorophenlylboronic acid (0.809 g, 4.60 mmol), potassium carbonate (0.954 g, 6.90 mmol) and tetrakis(triphenylphosphine)palladium (0.399 g, 15 mol %). 1H NMR (CDCl3): 8.09 (d, J=8.58 Hz, 1H), 8.04 (m, 1H), 7.97 (s, 1H), 7.93 (m, 1H), 7.74 (m, 2H), 7.62 (m, 5H), 7.38 (m, 4H), 7.16 (m, 2H). 13C NMR (CDCl3): 152.76, 150.26 138.35, 136.28, 133.52, 132.98, 130.32, 130.12, 129.77, 129.43, 128.25, 128.09, 127.28, 126.72, 126.52, 126.13, 126.02, 125.48, 115.92, 115.86, 115.77, 115.72. 19F NMR (CDCl3): 134.38 (m), 161.64 (m). λAbs=395 nm (DCM), λfluo=418 nm (DCM). Yield (purified)=75%, Yield (sublimed)=91%. MS (m/z, %): 434.3 (M+, 100). GC retention time=7.07 minutes.
Synthesis of Compound 11 (“SF319”): 9-(3-Trifluoromethylphenyl)-10-(naphthalene-2-yl)anthracene. Compound 11 was synthesized using an identical procedure to Compound 9 as described above, with the exception of the amount of solvent used (Toluene/Ethanol/Water, 287 mL), and 3-trifluoromethylphenlylboronic acid (1.268 g, 6.68 mmol) being used as the boronic acid, which was combined with 9-bromo-10-(naphthalene-2-yl)anthracene (1.280 g, 3.34 mmol), 3-trifluorophenlylboronic acid (1.268 g, 6.68 mmol), potassium carbonate (1.385 g, 10.02 mmol) and Tetrakis(triphenylphosphine)palladium (0.578 g, 15 mol %). 1H NMR (CDCl3): 8.10 (d, J=8.73 Hz, 1H), 8.04 (m, 1H), 7.99 (s, 1H), 7.93 (m, 1H), 7.78 (m, 6H), 7.62 (m, 5H), 7.35 (m, 4H). 13C NMR (CDCl3): 140.17, 137.87, 136.47, 135.34, 134.91, 133.54, 132.95, 131.38, 131.06, 130.36, 130.17, 129.97, 129.56, 129.18, 128.23, 128.08, 127.38, 126.66, 126.53, 126.47, 125.74, 125.38, 124.65. 19F NMR (CDCl3): 62.34 (s). λAbs=395 nm (DCM), λfluo=419 nm (DCM). Yield (purified)=75%, Yield (sublimed)=90%. MS (m/z, %): 448.3 (M+, 100). GC retention time=6.89 minutes.
Synthesis of Compound 12 (“SF19”): 9-(2-tolyphenyl)-10-(naphthalene-2-yl)anthracene. Compound 12 was synthesized using an identical procedure to Compound 11 as described above, with the exception of 2-tolylboronic acid (1.033 g, 7.60 mmol) being used as the boronic acid, which was combined with 9-bromo-10-(naphthalene-2-yl)anthracene (1.457 g, 3.80 mmol), potassium carbonate (1.575 g, 11.4 mmol) and tetrakis(triphenylphosphine)-palladium (0.658 g, 15 mol %). 1H NMR (CDCl3): 8.10 (dd, J=8.60, 2.36 Hz, 1H), 8.03 (m, 2H), 7.94 (m, 1H), 7.76 (m, 2H), 7.63 (m, 5H), 7.47 (m, 3H), 7.33 (m, 5H). 13C NMR (CDCl3): 138.60, 138.09, 136.89, 136.77, 133.57, 132.90, 131.47, 130.46, 130.45, 130.28, 130.21, 129.80, 128.26, 128.24, 128.08, 128.05, 128.04, 127.30, 126.82, 126.57, 126.36, 126.05, 125.33, 125.29, 20.02. λAbs=397 nm (DCM), λfluo=415 nm (DCM). Yield (purified)=75%, Yield (sublimed)=73%. MS (m/z, %): 394.3 (M+, 100). GC retention time=7.81 minutes.
Synthesis of Compound 13 (“SF20”): 9-(3-tolyphenyl)-10-(naphthalene-2-yl)anthracene. Compound 13 was synthesized using an identical procedure to Compound 9 as described above, with the exception that 3-Tolylboronic acid (0.668 g, 5.06 mmol) was used as the boronic acid, which was combined with 9-bromo-10-(naphthalene-2-yl)anthracene (0.971 g, 2.53 mmol), potassium carbonate (1.05 g, 7.60 mmol) and tetrakis(triphenylphosphine)palladium (0.438 g, 15 mol). 1H NMR (CDCl3): 8.09 (d, J=8.04 Hz, 1H), 8.04 (m, 1H), 7.99 (s, 1H), 7.93 (m, 1H), 7.74 (m, 4H), 7.62 (m, 3H), 7.34 (m, 7H). 13C NMR (CDCl3): 139.13, 138.13, 137.66, 138.87, 133.58, 132.88, 132.13, 130.38, 130.20, 130.06, 129.75, 128.53, 128.42, 128.34, 128.09, 128.04, 127.29, 127.14, 126.55, 126.35, 125.23, 125.10, 31.09, 21.71. 19F NMR (CDCl3): 113.22 (m). λAbs=395 nm (DCM), λfluo=420 nm (DCM). Yield (purified)=69%, Yield (sublimed)=81%. MS (m/z, %): 394.3 (M+, 100). GC retention time=9.21 minutes.
Synthesis of Compound 14 (“SF21”): 9-(3,5-bis(Trifluoromethyl)phenyl)-10-(naphthalene-2-yl)anthracene. Compound 14 was synthesized using an identical procedure to Compound 9 as described above, with the exception of 3,5-bis(Trifluoromethyl)phenylboronic acid (0.998 g, 3.87 mmol) being used as the boronic acid, which was combined with 9-bromo-10-(naphthalene-2-yl)anthracene (0.744 g, 1.94 mmol), potassium carbonate (0.803 g, 5.81 mmol) and tetrakis(triphenylphosphine)palladium (0.335 g, 15 mol %). 1H NMR (CDCl3): 8.02 (m, 7H), 7.76 (m, 2H), 7.61 (m, 3H), 7.51 (m, 2H), 7.38 (m, 4H). 13C NMR (CDCl3): 207.07, 141.75, 138.81, 136.17, 133.57, 133.23, 133.03, 132.45, 132.04, 131.73, 130.28, 130.16, 129.89, 129.41, 128.27, 128.09, 127.62, 126.74, 126.57, 126.34, 125.83, 125.51, 31.07. 19F NMR (CDCl3): 62.59(s). λAbs=395 nm (DCM), λfluo=425 nm (DCM). Yield (purified)=58%, Yield (sublimed)=85%. MS (m/z, %): 516.3 (M+, 100). GC retention time=4.87 minutes.
Synthesis of Compound 15 (“SF1”): 9-(4-methylphenyl)-10-phenylanthracene. The following reagents were mixed in a reaction vessel: 9-bromo-10-phenylanthracene (1.45 g, 4.35 mmol); Tetrakis(triphenylphosphine)palladium (Pd(PPh3)4, 0.75 g, 0.65 mmol); potassium carbonate (K2CO3, 1.80 g, 13.05 mmol); and 8.70 mmol of a boronic acid. In the present example, 4-methylbenzeneboronic acid (1.18 g) was used as the boronic acid. The reaction vessel containing the mixture was placed on a heating plate mantle and stirred using a magnetic stirrer. The reaction vessel was also connected to a water condenser. A well stirred 333 ml solvent mixture containing a 1:25:0.15 volumetric ratio of toluene, ethanol and water, was prepared separately in a round-bottom flask. The flask containing the solvent mixture was sealed and degassed using N2 for a minimum of 30 minutes before a cannula was used to transfer the solvent mixture from the round-bottom flask to the reaction vessel without exposure to air. Once all of the solvent mixture was transferred, the reaction vessel was purged with nitrogen, and heated to a temperature of 65° C. while stirring at around 1200 RPM and left to react for at least 12 hours under a nitrogen environment. Once the reaction was determined to be complete, the mixture was cooled to room temperature before the solvent mixture was removed using a vacuum rotary evaporator. The contents of the flask were then re-dissolved in dichloromethane (DCM), and washed five times with NaOH solution, water, and brine. The organic phase was washed over magnesium sulfate and filtered. The resulting product was purified by passing through a silica gel plug column under vacuum suction. The DCM solvent was removed to produce the product in a powdered form. The powdered product was then further purified using train sublimation under reduced pressure of 20-50 mTorr and using CO2 as a carrier gas. 1H NMR (CDCl3): 7.72 (m, 4H), 7.58 (m, 3H), 7.49 (m, 2H), 7.41 (m, 4H), 7.33 (m, 4H), 2.55 (s, 3H). 13C NMR (CDCl3): 139.28, 137.38, 137.21, 137.07, 136.10, 131.48, 131.34, 130.13, 130.03, 129.25, 128.53, 127.57, 127.20, 127.08, 125.10, 125.02, 21.55. λAbs=393 nm (iPrOH), λfluo=408.03 nm (iPrOH). Yield (purified)=53%, Yield (sublimed)=73%
Synthesis of Compound 16 (“SF7”): Synthesis of 9-(4-trifluoromethylphenyl)-10-phenylanthracene. Compound 16 was synthesized using an identical procedure to Compound 15 as described above, with the exception of 4-(trifluoromethyl)benzeneboronic acid (1.43 g, 7.52 mmol) being used as the boronic acid, which was combined with 9-bromo-10-phenylanthracene (1.25 g, 3.76 mmol), K2CO3 (1.60 g, 11.28 mmol) and Pd(PPh3)4 (0.65 g, 0.56 mmol). 1H NMR (CDCl3): 7.89 (d, 2H), 7.73 (m, 2H), 7.60 (m, 7H), 7.49 (m, 2H), 7.36 (m, 4H). 13C NMR (CDCl3): 143.31, 138.95, 135.32, 131.92, 131.37, 129.99, 129.86, 128.60, 127.74, 127.30, 126.48, 125.87, 125.60, 125.58, 125.27, 123.16. 19F NMR (CDCl3): −62.31 (s, 3F). λAbs=392 nm (iPrOH), λfluo=406.96 nm (iPrOH). Yield (purified)=53%, Yield (sublimed)=67%.
Synthesis of Compound 17 (“SF5”): 9-(4-tert-butylphenyl)-10-phenylanthracene. Compound 17 was synthesized using an identical procedure to Compound 15 as described above, with the exception that 4-tert-butylbenzeneboronic acid (1.38 g, 7.76 mmol) was used as the boronic acid, which was combined with 9-bromo-10-phenylanthracene (1.29 g, 3.88 mmol), K2CO3 (1.61 g, 11.64 mmol) and Pd(PPh3)4 (0.67 g, 0.58 mmol). 1H NMR (CDCl3): 7.72 (m, 4H), 7.58 (m, 5H), 7.50 (m, 2H), 7.42 (m, 2H), 7.33 (m, 4H), 1.49 (s, 9H). 13C NMR (CDCl3): 150.41, 139.32, 137.50, 137.02, 135.99, 131.49, 131.08, 130.17, 130.04, 128.54, 127.57, 127.32, 127.05, 125.40, 125.11, 124.99, 34.90. λAbs=393 nm (iPrOH), λfluo=408.03 nm (iPrOH).
Synthesis of Compound 18 (“SF24”): 9-(3-trifluoromethylphenyl)-10-phenylanthracene. Compound 18 was synthesized using an identical procedure to Compound 15 as described above, with the exception of the volume of solvent (222 mL) and 3-(trifluoromethyl)benzeneboronic acid (0.95 g, 5.02 mmol) being used as the boronic acid, which was combined with 9-bromo-10-phenylanthracene (0.84 g, 2.51 mmol), K2CO3 (1.04 g, 7.53 mmol) and Pd(PPh3)4 (0.44 g, 0.38 mmol) at room temperature. 1H NMR (CDCl3): 7.84 (m, 1H), 7.74 (m, 5H), 7.60 (m, 5H), 7.50 (m, 2H), 7.37 (m, 4H). 13C NMR (CDCl3): 140.18, 138.97, 138.08, 135.19, 134.90, 131.38, 131.03, 130.00, 129.93, 129.15, 128.61, 128.23, 127.75, 127.32, 126.46, 125.68, 125.27, 124.61, 123.03. 19F NMR (CDCl3): −62.38 (s, 3F). λAbs=392 nm (iPrOH), λfluo=406.06 nm (iPrOH).
Synthesis of Compound 19 (“SF8”): 9-(3-methylphenyl)-10-phenylanthracene. Compound 19 was synthesized using an identical procedure to Compound 18 as described above, with the exception of 3-methylbenzeneboronic acid (0.79 g, 5.80 mmol) being used as the boronic acid, which was combined with 9-bromo-10-phenylanthracene (0.97 g, 2.90 mmol), K2CO3 (1.20 g, 8.70 mmol) and Pd(PPh3)4 (0.51 g, 0.44 mmol). 1H NMR (CDCl3): 7.72 (m, 4H), 7.56 (m, 6H), 7.34 (m, 7H), 2.49 (m, 3H). 13C NMR (CDCl3): 139.28, 139.13, 138.12, 137.49, 137.10, 132.13, 131.49, 130.01, 130.01, 128.54, 128.52, 128.40, 128.31, 127.59, 127.22, 127.08, 125.11, 125.05, 21.69. λAbs=392 nm (iPrOH), λfluo=406.06 nm (iPrOH).
Synthesis of Compound 20 (“SF357”): 9-(4-Trifluoromethoxyphenyl)-10-(naphthalene-1-yl)anthracene. Compound 20 was synthesized using an identical procedure to Compound 1, except 4-trifluoromethoxyphenylboronic acid (1.49 g, 7.82 mmol) was used as the boronic acid. 1H NMR (400 MHz, CDCl3) δ 8.06 (d, J=8.2 Hz, 1H), 8.01 (d, J=8.3 Hz, 1H), 7.86-7.67 (m, 5H), 7.61 (d, J=8.8 Hz, 2H), 7.55 (d, J=6.3 Hz, 1H), 7.52-7.41 (m, 3H), 7.37-7.30 (m, 2H), 7.27-7.18 (m, 3H), 7.13 (t, J=7.6 Hz, 1H). λAbs,max=376 nm (DCM), λfluo,max=430 nm (DCM).
Synthesis of Compound 21 (“SF170”): 9-(4-trifluorophenyl)-10-(phenanthrene-1-yl) anthracene. The following reagents were mixed in a 500 mL reaction vessel: 9-bromo-10-(phenanthracene-10-yl)anthracene (1.500 g, 3.91 mmol); tetrakis(triphenylphosphine) palladium(0) (Pd(PPh3)4, 0.678 g, 0.587 mmol); potassium carbonate (K2CO3, 1.623 g, 11.7 mmol); and 7.82 mmol of a boronic acid. In the present example, 4-Trifluoromethylphenylboronic acid (1.49 g) was used as the boronic acid. The reaction vessel containing the mixture was placed on a heating plate mantle and stirred using a magnetic stirrer. The reaction vessel was also connected to a water condenser. A well stirred 300 ml solvent mixture containing a 25:3 volumetric ratio of N,N-dimethylformamide (DMF) and water was prepared separately in a round-bottom flask. The flask containing the solvent mixture was sealed and degassed using N2 for a minimum of 30 minutes before a cannula was used to transfer the solvent mixture from the round-bottom flask to the reaction vessel without exposure to air. Once all of the solvent mixture was transferred, the reaction vessel was purged with nitrogen, and heated to a temperature of 65° C. while stirring at around 1200 RPM and left to react for at least 12 hours under a nitrogen environment. Once the reaction was determined to be complete, the mixture was cooled to room temperature before being transferred to a 2 L beaker. 1500 mL of water was slowly added to the beaker while gently stirring the mixture to cause separation into two phases. The precipitate was filtered out and dried to produce a powdered product. The powdered product was then further purified using train sublimation under reduced pressure of 20-50 mTorr and using CO2 as a carrier gas. An observed yield of 139.2 mol % (2.40 g) was obtained after synthesis, and an overall molar yield of 63.2 mol %, after train sublimation. GC/MS elution time 12.136 min with an abundance of 6.5×106. 1H NMR (400 MHz, CDCl3) δ 8.87 (dd, J=8.4, 3.6 Hz, 2H), 7.90 (t, J=7.1 Hz, 3H), 7.85 (s, 1H), 7.81-7.74 (m, 1H), 7.74-7.69 (m, 1H), 7.65 (dd, J=13.9, 7.8 Hz, 5H), 7.58 (d, J=8.8 Hz, 2H), 7.37-7.29 (m, 3H), 7.24-7.18 (m, 3H). λAbs,max=377 nm (DCM), λfluo,max=432 nm (DCM).
Synthesis of Compound 22 (“SF173”): 9-(4-Tert-butylpheny)-10-(phenanthrene-1-yl)anthracene. Compound 22 was synthesized using an identical procedure to compound 21 as described above, with the exception that 4-Tert-butylphenylboronic acid (1.39 g, 7.82 mmol) was used as the boronic acid. An observed yield of 100.3 mol % (1.69 g) was obtained after synthesis, and an overall molar yield of 67.1 mol %, after train sublimation. GC/MS elution time 22.185 min with an abundance of 1.1×106. 1H NMR (400 MHz, CDCl3) δ 8.06 (d, J=8.3 Hz, 2H), 8.01 (d, J=8.2 Hz, 2H), 7.73-7.61 (m, 6H), 7.56-7.32 (m, 10H), 7.27-7.06 (m, 10H). λAbs,max=378 nm (DCM), λfluo,max=436 nm (DCM).
In addition to the above, the following Compounds 23-36 were synthesized: 9-(3-(naphthalen-1-yl)phenyl)-10-(naphthalen-1-yl)anthracene (Compound 23 (“SF168”)); 9-(3-(naphthalen-1-yl)phenyl)-10-(phenanthren-9-yl)anthracene (Compound 24 (“SF169”)); 2,6-bis(4-fluorophenyl)-9,10-di(naphthalen-2-yl)anthracene (Compound 25 (“SF3”)); 2,6-bis(4-tert-butyl)phenyl)-9,10-di(naphthalen-2-yl)anthracene (Compound 26 (“SF2”)); 9,10-di(naphthalen-2-yl)-2-(4-(trifluoromethyl)phenyl)anthracene (Compound 27 (“SF 157”)); 9-(4-trifluoromethoxyphenyl)-10-(naphthalene-2-yl)anthracene (Compound 28 (“SF315”)); 9,10-diphenylanthracene (Compound 29); 9-(4-methoxyphenyl)-10-phenylanthracene (Compound 30); 9-(4-fluorophenyl)-10-phenylanthracene (Compound 31); 9-phenyl-10-(3,4,5-trifluorophenyl)anthracene (Compound 32); 9-(2-methylphenyl)-10-phenylanthracene (Compound 33); 9-phenyl-10-(phenanthren-9-yl)anthracene (Compound 34); 9-(3-chloro-4-fluorophenyl)-10-phenylanthracene (Compound 35 (“SF0”)); and 9-(3,4,5-trifluorophenyl)-10-(phenanthren-9-yl)anthracene (Compound 36 (“SF171”)).
Example 1: Low Rate Evaluation of Compounds 1-5. In order to characterize an effect of using various materials to form a nucleation inhibiting coating, a series of samples were prepared using each of Compounds 1 to 5 to form the nucleation inhibiting coating.
As used in the examples herein, a reference to a layer thickness of a material refers to an amount of the material deposited on a target surface (or target region(s) of the surface in the case of selective deposition), which corresponds to an amount of the material to cover the target surface with a uniformly thick layer of the material having the referenced layer thickness. By way of example, depositing a layer thickness of 10 nm indicates that an amount of the material deposited on the surface corresponds to an amount of the material to form a uniformly thick layer of the material that is 10 nm thick. It will be appreciated that, for example, due to possible stacking or clustering of molecules or atoms, an actual thickness of the deposited material may be non-uniform. For example, depositing a layer thickness of 10 nm may yield some portions of the deposited material having an actual thickness greater than 10 nm, or other portions of the deposited material having an actual thickness less than 10 nm. A certain layer thickness of a material deposited on a surface can correspond to an average thickness of the deposited material across the surface.
A series of samples were fabricated by depositing an approximately 20 nm thick organic layer formed by 2-(4-(9,10-di(naphthalene-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo-[D]imidazole (LG201) over a glass substrate, followed by deposition of a nucleation inhibiting coating having a thickness of about 30 nm over the LG201 organic layer. The surface of the nucleation inhibiting coating was then subjected to open mask deposition of magnesium. Each sample was subjected to a magnesium vapor flux having an average evaporation rate of about 2.5 Å/s. In conducting the deposition of the magnesium coating, a deposition time of about 2000 seconds was used in order to obtain a reference layer thickness of magnesium of about 500 nm.
Once the samples were fabricated, optical transmission measurements were taken to determine the relative amount of magnesium deposited on the surface of the nucleation inhibiting coating. As will be appreciated, relatively thin magnesium coatings having, for example, thickness of less than a few nm are substantially transparent. However, light transmission decreases as the thickness of the magnesium coating is increased. Accordingly, the relative performance of various nucleation inhibiting coating materials may be assessed by measuring the light transmission through the samples, which directly correlates to the amount or thickness of magnesium coating deposited thereon from the magnesium deposition process. The material used to form the nucleation inhibiting coating in each sample, and the optical transmission measurement for each sample are summarized in Table 3 below. In calculating the optical transmission measurement, any loss or absorption of light caused by the presence of the glass substrate, the LG201 organic layer, and the nucleation inhibiting coating was subtracted from the measured transmittance. As such, the optical transmission value provided in Table 3 reflects solely the transmission of light (taken at wavelength of about 550 nm) through any magnesium coating which may be present on the surface of the nucleation inhibiting coating.
Example 2: Low Rate Evaluation of Compounds 6-22. In order to characterize an effect of using various materials to form a nucleation inhibiting coating, a series of samples were prepared using each of Compounds 6, 7 and 9 to 22 for forming the nucleation inhibiting coating.
The series of samples were fabricated by depositing a nucleation inhibiting coating over glass substrate. The surface of the nucleation inhibiting coating was then subjected to open mask deposition of magnesium. Each sample was subjected to a magnesium vapor flux having an average evaporation rate of about 2 Å/s. In conducting the deposition of the magnesium coating, a deposition time of about 1000 seconds was used in order to obtain a reference layer thickness of magnesium of about 200 nm.
The material used to form the nucleation inhibiting coating in each sample, and the optical transmission measurement for each sample are summarized in Table 4 below.
Based on the above, it can be seen that relatively high optical transmission of above 90% was measured for samples fabricated using Compounds 1 to 7 and 9 to 22 as the nucleation inhibiting coating material. As explained above, high optical transmission can directly be attributed to a relatively small amount of magnesium coating, if any, being present on the surface of the nucleation inhibiting coating to absorb the light being transmitted through the sample. Accordingly, these nucleation inhibiting coating materials generally exhibit relatively low affinity or initial sticking probability to magnesium and thus may be particularly useful for achieving selective deposition and patterning of magnesium coating in certain applications. In contrast, samples fabricated using Compounds 29 to 34 as the nucleation inhibiting coating material exhibited relatively low or no optical transmission, indicating that a substantial thickness of magnesium coating was deposited. Accordingly, Compounds 29-34 have been found to generally perform poorly as a nucleation inhibiting coating material.
As used in this and other examples described herein, a reference layer thickness refers to a layer thickness of magnesium that is deposited on a reference surface exhibiting a high initial sticking coefficient (e.g., a surface with an initial sticking coefficient of about or close to 1.0). Specifically, for these examples, the reference surface was a surface of a quartz crystal positioned inside a deposition chamber for monitoring a deposition rate and the reference layer thickness. In other words, the reference layer thickness does not indicate an actual thickness of magnesium deposited on a target surface (i.e., a surface of the nucleation inhibiting coating). Rather, the reference layer thickness refers to the layer thickness of magnesium that would be deposited on the reference surface upon subjecting the target surface and reference surface to identical magnesium vapor flux for the same deposition period (i.e. the surface of the quartz crystal). As would be appreciated, in the event that the target surface and reference surface are not subjected to identical vapor flux simultaneously during deposition, an appropriate tooling factor may be used to determine and monitor the reference thickness.
Example 3: High Rate Evaluation of Compounds 1-5. In order to determine what effects the magnesium evaporation rate may have on the nucleation inhibiting properties of various materials, a series of samples were prepared using each of compounds 1-5 to form the nucleation inhibiting coating and then exposed to relatively high magnesium vapor flux. A series of samples were fabricated by depositing an approximately 20 nm thick organic layer formed LG201 over a glass substrate, followed by deposition of a nucleation inhibiting coating having a thickness of about 30 nm over the LG201 organic layer. The samples were subjected to a magnesium flux having an average deposition rate of about 10 Å/s, as measured using the reference surface. In conducting the deposition of the magnesium coating, a deposition time of about 500 seconds was used in order to obtain a reference layer thickness of magnesium of about 500 nm.
Once the samples were fabricated, optical transmission measurements were taken to determine the relative amount of magnesium deposited on the surface of the nucleation inhibiting coating. The thickness of the nucleation inhibiting coating and the optical transmission measurement for each sample is summarized in Table 4 below. In calculating the optical transmission measurement, any loss or absorption of light caused by the presence of the glass substrate and the nucleation inhibiting coating was subtracted from the measured transmittance. As such, the optical transmission value provided in Table 4 reflects solely the transmission of light (taken at wavelength of about 550 nm) through any magnesium coating which may be present on the surface of the nucleation inhibiting coating.
Example 4: High Rate Evaluation of Compounds 6-22. In order to determine what effects the magnesium evaporation rate may have on the nucleation inhibiting properties of various materials, a series of samples were prepared using each of compounds 6-22 to form the nucleation inhibiting coating and then exposed to relatively high magnesium vapor flux. A series of samples were fabricated by depositing a nucleation inhibiting coating over glass substrates. The samples were subjected to a magnesium flux having an average deposition rate of about 10 Å/s, as measured using the reference surface. In conducting the deposition of the magnesium coating, a deposition time of about 200 seconds was used in order to obtain a reference layer thickness of magnesium of about 200 nm.
Once the samples were fabricated, optical transmission measurements were taken to determine the relative amount of magnesium deposited on the surface of the nucleation inhibiting coating. The thickness of the nucleation inhibiting coating and the optical transmission measurement for each sample is summarized in Table 6 below. In calculating the optical transmission measurement, any loss or absorption of light caused by the presence of the glass substrate and the nucleation inhibiting coating was subtracted from the measured transmittance. As such, the optical transmission value provided in Table 6 reflects solely the transmission of light (taken at wavelength of about 550 nm) through any magnesium coating which may be present on the surface of the nucleation inhibiting coating.
Based on the above, it can be seen that relatively high optical transmission of above 90% was measured only for sample fabricated using Compounds 4, 6, 7, 8, 9, 10, 11, 1 6, 17, 21 and 22 as the nucleation inhibiting coating material. As explained above, high optical transmission can directly be attributed to a relatively small amount of magnesium coating, if any, being present on the surface of the nucleation inhibiting coating. Accordingly, such nucleation inhibiting coating material may be particularly useful for achieving selective deposition and patterning of magnesium coating in certain applications. For example, such material may be particularly suitable for applications in which the deposition rate of magnesium coating is substantially higher than about 2 Å/s. In addition, samples fabricated using Compounds 29 to 34 as the nucleation inhibiting coating material exhibited no optical transmission, indicating that a substantial thickness of magnesium coating was deposited. Accordingly, Compounds 29-34 have been found to generally perform poorly as a nucleation inhibiting coating material.
The samples fabricated using Compound 5, 12, 13, 14, 19 and 20 as the nucleation inhibiting coating material exhibited optical transmission of about 66%, 33%, 35%, 49%, 46%, and 36%, respectively. While it is generally more favorable to use a material exhibiting higher optical transmission and thus superior nucleation inhibiting properties (i.e. low initial sticking probability) for applications requiring highly selective deposition of magnesium coating, materials such as Compound 5, 12, 13, 14, 19 and 20 may nevertheless be useful in forming the nucleation inhibiting coating for certain applications.
Samples fabricated using Compounds 1, 2, 15 and 18 all exhibited relatively low optical transmission. In particular, samples fabricated using Compound 15 and Compound 18 exhibited no transmission. This is indicative of a relatively large amount or thick layer of magnesium coating being deposited on the surface of the nucleation inhibiting coating, which results in significant absorption of light. Accordingly, these materials may be undesirable for use in achieving selective deposition of magnesium coating, particularly in applications requiring selective deposition of a relatively thick magnesium coating at a high deposition rate greater than about 2 Å/s (e.g. deposition rate of about 10 Å/s).
By comparing the results of Example 3 and 4 to those of Example 1 and 2, it has been determined, somewhat surprisingly, that some materials substantially inhibit deposition of magnesium thereon when subjected to magnesium vapor flux at relatively low deposition rate or evaporation rate, but the degree to which magnesium deposition is inhibited is substantially decreased when a relatively high deposition rate or evaporation rate of magnesium is used. In other words, it has been observed that selective deposition of magnesium coating may be successfully achieved using certain nucleation inhibiting coating materials (such as, for example, Compounds 1, 2, 15, and 18) at relatively low magnesium deposition rate of about 2 Å/s. However, at relatively high deposition rate of about 10 Å/s, highly selective deposition of magnesium coating could not successfully be achieved using the same nucleation inhibiting coating materials.
It has also been observed that some nucleation inhibiting coating materials appear to be effective at inhibiting deposition of magnesium thereon, irrespective of the magnesium deposition rate used in these examples. Based on the experimental results, Compounds 4, 6, 7, 8, 9, 10, 11, 16, 17, 21, and 22 may be used to form an effective nucleation inhibiting coating for achieving highly selective deposition of magnesium coating at magnesium deposition rate of at least up to about 10 Å/s.
In addition, it has also been found that samples fabricated similarly to those of Example 4 except using Compounds 23-28, 35 and 36 as the nucleation inhibiting coating also exhibited relatively high light transmission, thus indicating that such materials may also be suitable for forming the nucleation inhibiting coating in at least some applications.
Without wishing to be bound by a particular theory, it is postulated, based on the theory of nucleation and growth discussed above, that surfaces formed by depositing materials such as Compound 1 generally exhibit a relatively low desorption energy (Edes) for adsorbed magnesium adatoms, a high activation energy (ES) for diffusion of a magnesium adatom, or both. In this way, the critical nucleation rate ({dot over (N)}i), which is determined according to the equation below, remains relatively low even when the vapor impingement rate of magnesium ({dot over (R)}) is increased, thus substantially inhibiting deposition of magnesium.
It is postulated that the temperature of the substrate may be increased when the vapor impingement rate (i.e. the evaporation rate) is increased. For example, the evaporation source is typically operated at a higher temperature when the evaporation rate is increased. Accordingly, at higher evaporation rate, the substrate may be subjected to higher level of thermal radiation, which can heat up the substrate. Other factors, which may result in increased substrate temperature, include heating of the substrate caused by energy transfer from greater number of evaporated molecules being incident on the substrate surface, as well as increased rate of condensation or desublimation of molecules on the substrate surface releasing energy in the process and causing heating.
For further clarity, the term “selectivity” when used in the context of nucleation inhibiting coating would generally be understood to refer to the degree to which the nucleation inhibiting coating inhibits or prevents deposition of the conductive coating thereon, upon being subjected to the vapor flux of the material used to form the conductive coating. For example, a nucleation inhibiting coating exhibiting relatively high selectivity for magnesium would generally better inhibit or prevent deposition of magnesium coating thereon compared to a nucleation inhibiting coating having relatively low selectivity. In general, it has been observed that a nucleation inhibiting coating exhibiting relatively high selectivity would also exhibit relatively low initial sticking probability, and a nucleation inhibiting coating exhibiting relatively low selectivity would exhibit relatively high initial sticking probability.
Example 4. A series of kinetic Monte Carlo (KMC) calculations were conducted to simulate the deposition of metallic adatoms on surfaces exhibiting various activation energies. Specifically, the calculations were conducted to simulate the deposition of metallic adatoms, such as magnesium adatoms, on surfaces having varying activation energy levels associated with desorption (Edes), diffusion (Es), dissociation (Ei), and reaction to the surface (Eb) by subjecting such surfaces to evaporated vapor flux at a constant rate of monomer flux.
The rate (R) at which desorption, diffusion, or dissociation occurs is calculated from the frequency of attempt (ω), activation energy of the respective event (E), the Boltzmann constant (kB), and the temperature of the system (T), in accordance with the equation provided below:
For the purpose of the above calculations, i, the critical cluster size (i.e. critical number of adatoms to form a stable nucleus) was selected to be 2. The activation energy of diffusion for adatom-adatom interaction was selected to be greater than about 0.6 eV, the activation energy of desorption for adatom-adatom interaction was selected to be greater than about 1.5 eV, and the activation energy of desorption for adatom-adatom interaction was selected to be greater than about 1.25 times the activation energy of desorption for surface-adatom interaction. The above values and conditions were selected based on the values reported for magnesium-magnesium interactions. For the purpose of the simulations, a temperature (T) of 300 K was used. The calculations were repeated using values reported for other metal adatom-metal adatom activation interactions, such as that of tungsten-tungsten. The above referenced values have been reported, for example, in Neugbauer, C. A., 1964, Physics of Thin Films, 2, 1, Structural Disorder Phenomena in Thin Metal Films.
Based on the results of the simulations, a cumulative sticking probability was determined by calculating the fraction of the number of adsorbed monomers which remain on a surface (Nads) out of the total number of monomers which impinged on the surface (Ntotal) over a simulated period, in accordance with the equation provided below:
The simulations were conducted to simulate depositions using a vapor flux rate corresponding to about 2 Å/s over a deposition period greater than about 8 minutes, which corresponded to a time period for depositing a film having a reference thickness greater than about 96 nm.
For typical surfaces, the desorption activation energy (Edes) is generally greater than or equal to the diffusion activation energy (Es). Based on the simulations, it has now been found, at least in some cases, that surfaces exhibiting a relatively small difference between the desorption activation energy (Edes) and the diffusion activation energy (Es) may be particularly useful in acting as surfaces of nucleation inhibiting coatings. In some embodiments, the desorption activation energy is greater than or equal to the diffusion activation energy of the surface and is less than or equal to about 1.1 times, less than or equal to about 1.3 times, less than or equal to about 1.5 times, less than or equal to about 1.6 times, less than or equal to about 1.75 times, less than or equal to about 1.8 times, less than or equal to about 1.9 times, less than or equal to about 2 times, or less than or equal to about 2.5 times the diffusion activation energy of the surface. In some embodiments, the difference (e.g., in terms of absolute value) between the desorption activation energy and the diffusion activation energy is less than about or equal to about 0.5 eV, less than or equal to about 0.4 eV, less than or equal to about 0.35 eV, and more preferably less than or equal to about 0.3 eV, or less than or equal to about 0.2 eV. In some embodiments, the difference between the desorption activation energy and the diffusion activation energy is between about 0.05 eV and about 0.4 eV, between about 0.1 eV and about 0.3 eV, or between about 0.1 eV and about 0.2 eV.
It has also now been found, at least in some cases, that surfaces exhibiting a relatively small difference between the desorption activation energy (Edes) and the dissociation activation energy (Ei) may be particularly useful in acting as surfaces of nucleation inhibiting coatings. In some embodiments, the desorption activation energy (Edes) is less than or equal to a multiplier times the dissociation activation energy (Ei). In some embodiments, the desorption activation energy is less than or equal to about 1.5 times, less than or equal to about 2 times, less than or equal to about 2.5 times, less than or equal to about 2.8 times, less than or equal to about 3 times, less than or equal to about 3.2 times, less than or equal to about 3.5 times, less than or equal to about 4 times, or less than or equal to about 5 times the dissociation activation energy of the surface.
It has also now been found, at least in some cases, that surfaces exhibiting a relatively small difference between the diffusion activation energy (Es) and the dissociation activation energy (Ei) may be particularly useful in acting as surfaces of nucleation inhibiting coatings. In some embodiments, the diffusion activation energy (Es) is less than or equal to a multiplier times the dissociation activation energy (Ei). In some embodiments, the diffusion activation energy is less than or equal to about 2 times, less than or equal to about 2.5 times, less than or equal to about 2.8 times, less than or equal to about 3 times, less than or equal to about 3.2 times, less than or equal to about 3.5 times, less than or equal to about 4 times, or less than or equal to about 5 times the dissociation activation energy of the surface.
In some embodiments, the relationship between the desorption activation energy (Edes), the diffusion activation energy (Es), and the dissociation activation energy (Ei) of a surface of a nucleation inhibiting coating may be represented as follows:
E
des
≤a*E
s
≤β*E
i
wherein a may be any number selected from a range of between about 1.1 and about 2.5, and β may be any number selected from a range of between about 2 and about 5. In some further embodiments, a may be any number selected from a range of between about 1.5 and about 2, and β may be any number selected from a range of between about 2.5 and about 3.5. In another further embodiment, a is selected to be about 1.75 and β is selected to be about 3.
It has now been found that surfaces having the following relationship may, at least in certain cases, exhibit a cumulative sticking probability of less than about 0.1 for magnesium vapor:
E
des≤1.75*Es≤3*Ei
Accordingly, surfaces having the above activation energy relationship may be particularly advantageous for use as surfaces of nucleation inhibiting coatings in some embodiments.
It has also now been found that surfaces which, in addition to the above activation energy relationships, exhibit a relatively small difference of less than or equal to about 0.3 eV between the diffusion activation energy and the dissociation activation energy may be particularly useful in certain applications, in which a cumulative sticking probability less than about 0.1 is desired. The energy difference (ΔEs-i) between the diffusion activation energy (Es) and the dissociation activation energy (Ei) may be calculated according to the following equation:
ΔEs-i=Es−Ei
For example, it has now been found that, at least in some cases, surfaces wherein the energy difference between the diffusion activation energy and the dissociation activation energy is less than or equal to about 0.25 eV exhibits a cumulative sticking probability of less than or equal to about 0.07 for magnesium vapor. In other examples, AEs, less than or equal to about 0.2 eV results in a cumulative sticking probability of less than or equal to about 0.05, ΔEs-i less than or equal to about 0.1 eV results in a cumulative sticking probability of less than or equal to about 0.04, and ΔEs-1 less than or equal to about 0.05 eV results in a cumulative sticking probability of less than or equal to about 0.025.
Accordingly, in some embodiments, surfaces are characterized by: a is any number selected from a range of between about 1.1 and about 2.5, or more preferably a range of between about 1.5 and about 2, such as for example about 1.75, and β is any number selected from a range of between about 2 and about 5, or more preferably a range of between about 2.5 and about 3.5, such as for example about 3, in the following inequality relationship:
E
des
≤α*E
s
≤β*E
i
and wherein ΔEs-i calculated according to the following equation is less than or equal to about 0.3 eV, less than or equal to about 0.25 eV, less than or equal to about 0.2 eV, less than or equal to about 0.15 eV, less than or equal to about 0.1 eV, or less than or equal to about 0.05 eV in the following equation:
ΔEs-i=Es−Ei
The results of the calculations were also analyzed to determine the simulated initial sticking probability, which, in the present example, was specified to be the sticking probability of magnesium on a surface upon depositing onto such surface that yields a magnesium coating having an average thickness of about 1 nm. Based on the analysis of the results, it has now been found that, at least in some cases, surfaces wherein the desorption activation energy (Edes) is less than about 2 times the diffusion activation energy (Es), and the diffusion activation energy (Es) is less than about 3 times the dissociation activation energy (Ei) generally exhibits a relatively low initial sticking probability of less than about 0.1.
Without wishing to be bound by any particular theory, it is postulated that the activation energies of various events and the respective relationships between these energies as described above would generally apply to surfaces wherein the activation energy of adatom reaction to the surface (Eb) is greater than the desorption activation energy (Edes). For surfaces wherein the activation energy of adatom reaction to the surface (Eb) is less than the desorption activation energy (Edes), it is postulated the initial sticking probability of adatoms on such surface would generally be greater than about 0.1.
It would be appreciated that various activation energies described above are treated as non-negative values measured in any unit of energy, such as in electron volt (eV). In such cases, the various inequalities and equations relating to activation energies discussed above may be generally applicable.
While simulated values of various activation energies have been discussed above, it will be appreciated that these activation energies may also be experimentally measured and/or derived using various techniques. Examples of techniques and instruments which may be used for such purpose include, but are not limited to, thermal desorption spectroscopy, field ion microscopy (FIM), scanning tunneling microscopy (STM), transmission electron microscopy (TEM), and neutron activation-tracer scanning (NATS).
Generally, various activation energies described herein may be derived by conducting quantum chemistry simulations if the general composition and structure of the surface and adatoms are specified (e.g. through experimental measurements and analysis). For simulations, quantum chemistry simulations using methods such as, for example, single energy points, transition states, energy surface scan, and local/global energy minima may be used. Various theories such as, for example, Density Functional Theory (DFT), Hartree-Fock (HF), Self Consistent Field (SCF), and Full Configuration Interaction (FCI) may be used in conjunction with such simulation methods. As would be appreciated, various events such as diffusion, desorption and nucleation may be simulated by examining the relative energies of the initial state, the transition state and the final state. For example, the relative energy difference between the transition state and the initial state may generally provide a relatively accurate estimate of the activation energy associated with various events.
As used herein, the terms “substantially,” “substantial,” “approximately,” and “about” are used to denote and account for small variations. When used in conjunction with an event or circumstance, the terms can refer to instances in which the event or circumstance occurs precisely, as well as instances in which the event or circumstance occurs to a close approximation. For example, when used in conjunction with a numerical value, the terms can refer to a range of variation of less than or equal to ±10% of that numerical value, such as less than or equal to ±5%, less than or equal to ±4%, less than or equal to ±3%, less than or equal to ±2%, less than or equal to ±1%, less than or equal to ±0.5%, less than or equal to ±0.1%, or less than or equal to ±0.05%.
In the description of some embodiments, a component provided “on” or “over” another component, or “covering” or which “covers” another component, can encompass cases where the former component is directly on (e.g., in physical contact with) the latter component, as well as cases where one or more intervening components are located between the former component and the latter component.
The embodiments, illustratively described herein may suitably be practiced in the absence of any element or elements, limitation or limitations, not specifically disclosed herein. Thus, for example, the terms “comprising,” “including,” “containing,” etc. shall be read expansively and without limitation. Additionally, the terms and expressions employed herein have been used as terms of description and not of limitation, and there is no intention in the use of such terms and expressions of excluding any equivalents of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the claimed technology. Additionally, the phrase “consisting essentially of” will be understood to include those elements specifically recited and those additional elements that do not materially affect the basic and novel characteristics of the claimed technology. The phrase “consisting of” excludes any element not specified.
In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.
As will be understood by one skilled in the art, for any and all purposes, particularly in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as “up to,” “at least,” “greater than,” “less than,” and the like, include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member.
Although the present disclosure has been described with reference to certain specific embodiments, various modifications thereof will be apparent to those skilled in the art. Any examples provided herein are included solely for the purpose of illustrating certain aspects of the disclosure and are not intended to limit the disclosure in any way. Any drawings provided herein are solely for the purpose of illustrating certain aspects of the disclosure and may not be drawn to scale and do not limit the disclosure in any way. The scope of the claims appended hereto should not be limited by the specific embodiments set forth in the above description, but should be given their full scope consistent with the present disclosure as a whole. The disclosures of all documents recited herein are incorporated herein by reference in their entirety.
Other embodiments are set forth in the following claims.
This application claims the benefit of priority to U.S. Provisional Patent Application Nos. 62/625,710, filed on Feb. 2, 2018; 62/625,722 filed on Feb. 2, 2018; and 62/770,360, filed on Nov. 21, 2018, the disclosures of which are incorporated herein by reference in their entirety for any and all purposes.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2019/050839 | 1/2/2019 | WO | 00 |
| Number | Date | Country | |
|---|---|---|---|
| 62625710 | Feb 2018 | US | |
| 62625722 | Feb 2018 | US | |
| 62770360 | Nov 2018 | US |
