Patent Application
20230284502
This application claims priority to Korean Patent Application No. 10-2022-0028933, filed on Mar. 7, 2022, and all the benefits accruing therefrom under 35 U.S.C. § 119, the content of which in its entirety is herein incorporated by reference.
One or more embodiments relate to a display apparatus.
A display apparatus such as an organic light-emitting display apparatus produces an image by generating light based on the principle that holes and electrons injected from an anode and a cathode, respectively, recombine in an emission layer to emit light. For example, a desired color is expressed by a color combination of pixels that may each emit a color of light.
To this end, each pixel includes: a light-emitting device that may generate monochromatic light, such as white light or blue light; a quantum dot layer and a color filter for controlling the monochromatic light to be converted to a desired color of light, e.g., red light, green light, or blue light, for output. That is, when the light-emitting device of each pixel generates monochromatic light, the monochromatic light passes through the quantum dot layer and the color filter and is converted into one of red, green, and blue light, and then each color of light is emitted, thus realizing an image of a desired color by a color combination of the colors of light emitted from the pixels.
Provided is a display apparatus in which defects of a quantum dot layer due to permeation of oxygen or moisture is reduced.
Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure.
According to one or more embodiments, a display apparatus may include: a first substrate on which a light-emitting device may be located; and a light controller on the first substrate and corresponding to the light-emitting device, where the light controller may include an organic capping layer, a quantum dot layer and/or a scattering layer, and a color filter layer, and the organic capping layer is adjacent to the quantum dot layer or the scattering layer.
A monomer used in forming the organic capping layer and a monomer used in forming the quantum dot layer and/or the scattering layer may be the same type of monomer.
A monomer used in forming the organic capping layer may be an acrylic monomer.
A monomer used in forming the quantum dot layer and/or the scattering layer may be an acrylic monomer.
The light controller may include a quantum dot layer and a color filter layer, and the organic capping layer may be disposed between the quantum dot layer and/or the scattering layer, and the color filter layer.
The quantum dot layer and/or the scattering layer, and the organic capping layer may each be formed by an inkjet printer.
The quantum dot layer and/or the scattering layer, and the organic capping layer may each be cured simultaneously.
A monomer used in forming the organic capping layer may include hexamethylene diacrylate, tetraethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, or any combination thereof.
A thickness of the organic capping layer may be in a range of about 0.1 micrometers (μm) to about 10 μm.
The light controller may further include a low-refractive-index layer, and the low-refractive-index layer may be disposed between the quantum dot layer and/or the scattering layer, and the color filter layer.
The quantum dot layer may include a quantum dot, and the quantum dot may include a group II-VI semiconductor compound; a group III-V semiconductor compound; a group III-VI semiconductor compound; a group semiconductor compound; a group IV-VI semiconductor compound; a group IV element or compound; or any combination thereof.
The group II-VI semiconductor compound may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, or any combination thereof.
The group III-V semiconductor compound may include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, or any combination thereof.
The group semiconductor compound may include GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2S3, In2Se3, InTe, InGaS3, InGaSe3, or any combination thereof.
The group semiconductor compound may include AgInS, AgInS2, CuInS, CuInS2, CuGaO2, AgGaO2, AgAlO2, AgInGaS, or any combination thereof.
The group IV-VI semiconductor compound may include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, or any combination thereof.
The group IV element or compound may include Si, Ge, SiC, SiGe, or any combination thereof.
The display apparatus may further include a second substrate facing the first substrate,
The display apparatus may further include an inorganic capping layer, and the inorganic capping layer may be disposed between the organic capping layer and the light-emitting device, and the inorganic capping layer may be adjacent to (e.g., in contact with) the organic capping layer.
The light-emitting device of the display apparatus may be configured to emit blue light, red light, or light consisting of a combination thereof.
The light-emitting device of the display apparatus may be configured to emit light including light of a wavelength in a range of about 380 nanometers (nm) to about 780 nm, and
The color filter layer of the display apparatus may improve colorimetric purity of emitted light.
According to one or more embodiments, a light controller includes: a bank;
The light controller may further include a color filter layer.
Other aspects, features, and advantages other than those described above will become apparent from the following drawings, claims, and detailed description.
The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:
Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Throughout the disclosure, the expression “at least one of a, b or c” indicates only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.
As the inventive concept allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. Effects, features, and a method of achieving the inventive concept will be obvious by referring to example embodiments of the inventive concept with reference to the attached drawings. The inventive concept may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein.
Hereinafter, the inventive concept will be described in detail by explaining example embodiments of the inventive concept with reference to the attached drawings. Like reference numerals in the drawings denote like elements, and thus their description will be omitted.
It will be understood that, although the terms “first”, “second”, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.
In the embodiments described in the present specification, an expression used in the singular encompasses the expression of the plural, unless it has a clearly different meaning in the context.
“About” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the particular value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the particular quantity (i.e., the limitations of the measurement system). For example, “about” can mean within one or more standard deviations, or within ±30%, 20%, 10% or 5% of the stated value.
In the present specification, it is to be understood that the terms such as “including,” “having,” and “comprising” are intended to indicate the existence of the features or components disclosed in the specification, and are not intended to preclude the possibility that one or more other features or components may exist or may be added.
Sizes of components in the drawings may be exaggerated for convenience of explanation. In other words, since sizes and thicknesses of components in the drawings are arbitrarily illustrated for convenience of explanation, the following embodiments are not limited thereto.
When a specific example may be implemented differently, a specific process order may be performed differently from the described order. For example, two processes described in succession may be performed substantially simultaneously or may be performed in an order opposite to the described order.
It will be understood that when a layer, region, or component is referred to as being “connected to” another layer, region, or component, the layer, region, or component may be directly connected to the another layer, region, or component, or indirectly connected to the another layer, region, or component as intervening layer, region, or component is present. For example, it will be understood that when a layer, region, or component is referred to as being “electrically connected to” another layer, region, or component, the layer, region, or component may be directly electrically connected to the another layer, region, or component, or indirectly electrically connected to the another layer, region, or component as intervening layer, region, or component is present.
According to one or more embodiments, a display apparatus may include:
As shown in
In another embodiment, although not shown in
In still another embodiment, although not shown in
The light-emitting device 120 may have a structure in which an interlayer 123 including an emission layer may be disposed between the first electrode 122 and the second electrode 124, and holes and electrons injected from the two electrodes 122 and 124, respectively, may recombine in the emission layer in the interlayer 123, thus generate light. For example, red, green, and blue pixels may absorb, transmit, and/or generate light having a wavelength in a range of about 380 nanometers (nm) to about 780 nm. That is, for example, the light-emitting device 120 may generate light having a wavelength in a range of about 380 nm to about 500 nm, light having a wavelength of about 380 nm to about 650 nm, or light having a wavelength of about 380 nm to about 780 nm. The light controller of each pixel may convert the light into red, green, and blue. The light-emitting device 120 will be described in detail later.
A reference numeral 121 indicates a pixel circuit connected to the first electrode 122, and includes elements such as a thin-film transistor and a capacitor. Also, a reference numeral 130 indicates a thin-film encapsulation layer that protects the light-emitting device 120 by covering the same, and may be a single-layered film of an organic film or an inorganic film, or may be a multi-layered film in which an organic film and an inorganic film are alternately stacked. The inorganic film may include silicon oxide, silicon nitride, and/or silicon oxynitride, and the organic film may include polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, acryl-based resin (for example, polymethylmethacrylate or polyacrylic acid), or any combination thereof.
The light controllers may include an organic capping layer, a quantum dot layer and/or a scattering layer, and a color filter layer.
The quantum dot layers 230R and 230G, the scattering layer 230W, and the color filter layers 220R, 220G, and 220B may be prepared as the light controllers. The quantum dot layer 230R may convert blue light generated from the light-emitting device 120 into red light, and the quantum dot layer 230G may convert blue light generated from the light-emitting device 120 into green light. The color filter layers 220R, 220G, and 220B may increase color purity by filtering out stray light that may be partially mixed in the converted color. Here, the quantum dot layer 230R and the color filter layer 220R both may be provided in the red pixel and the quantum dot layer 230G and the color filter layer 220G both may be provided in the green pixel, whereas the scattering layer 230W and the blue color filter layer 220B may be provided in the blue pixel. The reason is that the light generated by the light-emitting device 120 is, for example, blue light. That is, blue light is not required to convert the light in the blue pixel, and blue light may pass through the scattering layer 230W only. Thus, the blue color filter layer 220B for filtering the stray light is provided. The scattering layer 230W may include a scatterer.
A reference numeral 260 denotes a low-refractive-index layer having the refractive index of about 1.2. The side-scattered light that has passed through the quantum dot layers 230R and 230G and the scattering layer 230W, is totally reflected at the interface of the low-refractive-index layer 260 due to the difference between the refractive index of the quantum dot layers 230R and 230G and the scattering layer 230W and the refractive index of the low-refractive-index layer 260, so that the light is re-scattered inside the quantum dot layers 230R and 230G and the scattering layer 230W. The low-refractive-index layer 260 may increase luminance by converting side scattering to front scattering.
In some embodiments, the light controller may further include a low-refractive-index layer, and the low-refractive-index layer may be disposed between the quantum dot layer and/or the scattering layer, and the color filter layer.
In an embodiment, the organic capping layer 400 and the quantum dot layers 230R and 230G may be physically in direct contact with each other. In addition, the organic capping layer 400 and the scattering layer 230W may be in direct contact physically with each other.
In an embodiment, a monomer included in the organic capping layer 400 and a monomer included in the quantum dot layers 230R and 230G and/or the scattering layer 230W may be monomers of the same series.
The quantum dot layer 230R and 230G may be formed by a solution process, for example, an inkjet process using an ink composition for forming quantum dots. The ink composition may include a quantum dot, a monomer, an initiator, and an additive. The additive may include, for example, a dispersant, a viscosity modifier, or any combination thereof. The ink composition may not include a solvent. The initiator may be a common initiator used to cure polymers.
The initiator may include, for example, TPO, Quantacure BMS, oxime-base compound as follows, or ethyl phenyl(2,4,6-trimethylbenzoyl)phosphinate):
The initiator may be included in an amount of about 0.1 percent by weight (wt %) to about 50 wt % based on 100 wt % of the monomer.
The additive may be included in an amount of about 0.1 wt % to about 50 wt % based on 100 wt % of the monomer.
The scattering layer 230W may be formed by a solution process, for example, an inkjet process using an ink composition for forming a scattering layer. For example, the ink composition may be an equivalent ink composition except for using a scatterer instead of a quantum dot in the ink composition for forming quantum dots. The scatterer may include, for example, titanium, silver, aluminum, or an oxide of any combination thereof.
The organic capping layer 400 may be formed by a solution process, for example, an inkjet process using an ink composition for forming an organic capping layer. In an embodiment, the ink composition may include a monomer, an initiator, and an additive. The additive may include, for example, a dispersant, a viscosity modifier, or any combination thereof. The ink composition may not include a solvent. The monomer, initiator, and additive used in the ink composition for forming an organic capping layer may be understood by referring to the descriptions of the monomer, initiator, and additive used in the ink composition for forming quantum dots.
First, after forming the quantum dot layers 230R and 230G and/or the scattering layer 230W with inkjet, the organic capping layer 400 may be formed with inkjet on the quantum dot layer 230R and 230G and/or the scattering layer 230W.
The thus formed organic capping layer 400 may be crosslinked with the quantum dot layer 230R and 230G and/or the scattering layer 230W by heat or light simultaneously. In this process, when an ink composition for forming quantum dots or ink composition for forming a scattering layer and an ink composition for forming an organic capping layer is in contact with each other, an inorganic material (e.g., quantum dots or a scatterer) may be diffused. However, as a viscosity of the ink composition for forming quantum dots or the ink composition for forming a scattering layer may be greater than a viscosity of the ink composition for forming an organic capping layer, such a diffusion may be reduced.
To reduce the diffusion, the ink composition for forming an organic capping layer may not be too different from the ink composition for forming quantum dots and/or the ink composition for forming a scattering layer. For example, the ink composition for forming an organic capping layer may be an ink composition from which an inorganic material (e.g., quantum dots) is removed from the ink composition for forming quantum dots or the ink composition for forming a scattering layer.
In an embodiment, for example, a monomer used in forming or included in the organic capping layer and a monomer used in forming or included in the quantum dot layer and/or the scattering layer may be monomers of the same series. For example, when a monomer used in forming or included in the organic capping layer is hydrophobic, a monomer used in forming or included in the quantum dot layer and/or the scattering layer may also be hydrophobic. For example, when a monomer used in forming or included in the organic capping layer is hydrophilic, a monomer used in forming or included in the quantum dot layer and/or the scattering layer may also be hydrophilic.
In an embodiment, for example, when the dispersant included in the ink composition for forming quantum dots or the ink composition for forming a scattering layer contains an amine moiety or an acid moiety, the dispersant included in the ink composition for forming an organic capping layer may also be an amine moiety or an acid moiety. For example, when the dispersant included in the ink composition for forming quantum dots or the ink composition for forming a scattering layer contains an amine moiety, and the dispersant included in the ink composition for forming an organic capping layer contains an amine moiety, precipitation may not occur. For example, when the dispersant included in the ink composition for forming quantum dots or the ink composition for forming a scattering layer contains an acid moiety, and the dispersant included in the ink composition for forming an organic capping layer contains an acid moiety, precipitation may not occur.
In an embodiment, for example, when the dispersant included in the ink composition for forming quantum dots or the ink composition for forming a scattering layer contains an amphiphilic moiety (with an amine moiety and an acid moiety), the dispersant included in the ink composition for forming an organic capping layer may also be an amphiphilic moiety.
In an embodiment, for example, when the dispersant included in the ink composition for forming quantum dots or the ink composition for forming a scattering layer contains an amine moiety or an acid moiety, and the dispersant included in the ink composition for forming an organic capping layer contains an amphiphilic moiety, precipitation may occur. Therefore, in this case, for example, the organic capping layer 400; and the quantum dot layer 230R and 230G or the scattering layer 230W may not be formed at the same time by crosslinking.
In an embodiment, a monomer used in forming or included in the organic capping layer may be an acrylic monomer.
In some embodiments, a monomer used in forming or included in the quantum dot layer and/or the scattering layer may be an acrylic monomer.
In some embodiments, a monomer used in forming or included in the organic capping layer may include hexamethylene diacrylate, tetraethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, or any combination thereof.
In some embodiments, a monomer used in forming or included in the quantum dot layer and/or the scatterer layer may include hexamethylene diacrylate, tetraethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, or any combination thereof.
In some embodiments, a thickness of the organic capping layer may be in a range of about 0.1 micrometers (μm) to about 10 μm. In some embodiments, a thickness of the organic capping layer may be in a range of about 0.5 μm to about 5.0 μm. when the thickness of the organic capping layer is less than 0.1 μm, the organic capping layer may not sufficiently cover the quantum dot layer, and when the thickness is greater than 10 μm, curing efficiency of the organic capping layer; and the quantum dot layer and/or the scatterer layer simultaneously may be poor.
In an embodiment, a vapor pressure of the ink composition for forming an organic capping layer may be in a range of about 10−6 mmHg to about 10−3 mmHg.
In an embodiment, a surface energy of the ink composition for forming an organic capping layer may be in a range of about 1 dyne/cm to about 20 dyne/cm.
In an embodiment, a viscosity of the ink composition for forming an organic capping layer may be in a range of about 1 cps to about 40 cps.
When the vapor pressure, the surface energy, and the viscosity of the ink composition for forming an organic capping layer is within these ranges, the ink composition for forming an organic capping layer may be suitable for a solution process, e.g., an inkjet process.
A reference numeral 240 in
A portion formed by overlapping the color filter layers 220R, 220G, and 220B between a bank 240 and the second substrate 210 may function as a black matrix.
One surface of the bank 240 facing the first substrate 110 may be hydrophobic. Light (for example, monochromatic light) generated from a light source (e.g., an organic light-emitting device) may pass through a quantum dot layer and a color filter and may be converted into one color of red, green, and blue and emitted.
In forming the bank 240, a bank composition is applied on a substrate and cured, and then undergoes a photolithography process. The bank composition includes a curable polymer, a photoresist compound, a fluorine-containing polymer, a black pigment, a scattering agent, and a solvent, wherein, when the bank composition is cured, the solvent evaporates completely.
The filling material 300 is located between the first substrate 110 and the second substrate 210, wherein the filling material functions as both a gap maintainer that maintains an appropriate distance between the two substrates 110 and 210 and a bonding agent. Accordingly, when the filling material 300 is coated between the two substrates 110 and 210, which are then bonded together, the filling material 300 firmly bonds the two substrates 110 and 210 while properly maintaining a gap therebetween.
The display apparatus having the structure may be manufactured according to a process shown in
First, as shown in
Then, the color filter layers 220R, 220G, and 220B may be patterned on the second substrate 210 as shown in
Next, on the low-refractive-index layer 260, as shown in
Next, as shown in
The quantum dot that is a photochromic particle included in the quantum dot layers 230R and 230G may include a group III-VI semiconductor compound; a group II-VI semiconductor compound; a group III-V semiconductor compound; a group III-VI semiconductor compound; a group semiconductor compound; a group IV-VI semiconductor compound; a group IV element or compound; or any combination thereof.
Examples of the group II-VI semiconductor compound may include a binary compound such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, or MgS; a ternary compound such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, or MgZnS; a quaternary compound such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, or HgZnSTe; or any combination thereof.
Examples of the group III-V semiconductor compound may include a binary compound such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, or InSb; a ternary compound such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, or InPSb; a quaternary compound such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, or InAlPSb; or any combination thereof. In some embodiments, the group III-V semiconductor compound may further include a group II element. Examples of the group III-V semiconductor compound further including the group II element may include InZnP, InGaZnP, InAlZnP, and the like.
Examples of the III-VI group semiconductor compound may include a binary compound such as GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2S3, In2Se3, InTe, and the like; a ternary compound such as InGaS3, InGaSe3, and the like; or any combination thereof.
Examples of the group semiconductor compound may include a ternary compound such as AgInS, AgInS2, CuInS, CuInS2, CuGaO2, AgGaO2, AgAlO2, a quaternary compound such as AgInGaS, or any combination thereof.
Examples of the group IV-VI semiconductor compound may include a binary compound such as SnS, SnSe, SnTe, PbS, PbSe, or PbTe; a ternary compound such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, or SnPbTe; a quaternary compound such as SnPbSSe, SnPbSeTe, or SnPbSTe; or any combination thereof.
The group IV element or compound may be a single element material such as Si or Ge; a binary compound such as SiC or SiGe; or any combination thereof.
Individual elements included in the multi-element compound, such as a binary compound, a ternary compound, and a quaternary compound, may be present in a particle thereof at a uniform or non-uniform concentration.
The quantum dot may have a single structure in which the concentration of each element included in the quantum dot is uniform or a core-shell double structure. In some embodiments, materials included in the core may be different from materials included in the shell.
The shell of the quantum dot may serve as a protective layer for preventing chemical denaturation of the core to maintain semiconductor characteristics and/or as a charging layer for imparting electrophoretic characteristics to the quantum dot. The shell may be a monolayer or a multilayer. An interface between a core and a shell may have a concentration gradient where a concentration of elements present in the shell decreases toward the core.
Examples of the shell of the quantum dot include metal, metalloid, or nonmetal oxide, a semiconductor compound, or a combination thereof. Examples of the metal oxide, metalloid, or nonmetal oxide may include: a binary compound such as SiO2, Al2O3, TiO2, ZnO, MnO, Mn2O3, Mn3O4, CuO, FeO, Fe2O3, Fe3O4, CoO, Co3O4, or NiO; a ternary compound such as MgAl2O4, CoFe2O4, NiFe2O4, or CoMn2O4; and any combination thereof. Examples of the semiconductor compound may include a group II-VI semiconductor compound; a group III-V semiconductor compound; a group III-VI semiconductor compound; a group I-III-VI semiconductor compound; a group IV-VI semiconductor compound; or any combination thereof. In some embodiments, the semiconductor compound may be CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, or any combination thereof.
The quantum dot may have a full width of half maximum (“FWHM”) of a spectrum of an emission wavelength of about 45 nm or less, about 40 nm or less, or about 30 nm or less. When the FWHM of the quantum dot is within this range, color purity or color reproducibility may be improved. In addition, because light emitted through the quantum dots is emitted in all directions, an optical viewing angle may be improved.
In addition, the quantum dot may be specifically, a spherical, pyramidal, multi-arm, or cubic nanoparticle, nanotube, nanowire, nanofiber, or nanoplate particle.
By adjusting the size of the quantum dot, the energy band gap may also be adjusted, thereby obtaining light of various wavelengths in the quantum dot emission layer. By using quantum dots of various sizes, a light-emitting device that may emit light of various wavelengths may be realized. In some embodiments, the size of the quantum dot may be selected such that the quantum dot may emit red, green, and/or blue light. In addition, the size of the quantum dot may be selected such that the quantum dot may emit white light by combining various light colors.
The scattering layer 230W may include, for example, titanium, silver, aluminum, or an oxide of any combination thereof.
After forming the quantum dot layers 230R and 230G and/or the scattering layer 230W, the organic capping layer 400 may be formed. The organic capping layer 400 may be, for example, formed by inkjet.
In some embodiments, the quantum dot layers 230R and 230G, the scattering layer 230W, and the organic capping layer 400 formed by inkjet may be crosslinked simultaneously (for example, less than 1 minute with ultraviolet (UV) of 390 nm) to thereby form the quantum dot layers 230R and 230G, the scattering layer 230W, and the organic capping layer 400 may be formed. By forming the organic capping layer 400, an N2 atmosphere is not required until the inorganic capping layer 270 is formed.
Next, post-baking is performed, and the inorganic capping layer 270 may be formed on the organic capping layer 400 by vapor-phase chemical vapor deposition. In this embodiment, as the inorganic capping layer 270 may be formed by vapor-phase chemical vapor deposition on the formed organic capping layer 400, vapor-phase chemical vapor deposition may not affect the quantum dot layers 230R and 230G.
The inorganic capping layer 270 may be a layer including an oxide of Si, N, any combination thereof, or an oxide of any combination thereof and may have a thickness of about 1,000 Å to about 10,000 Å.
Next, as shown in
The present embodiment illustrates a case in which the interlayer 123 including the emission layer is formed as a common layer across the entire pixel area. However, as shown in
The emission layer may include an organic light-emitting material or a light-emitting material.
The light-emitting device 120 will be described in detail.
In
The first electrode 122 may be formed by depositing or sputtering, on the substrate, a material for forming the first electrode 122. When the first electrode 122 is an anode, a high work function material that may easily inject holes may be used as a material for a first electrode.
The first electrode 122 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. When the first electrode 122 is a transmissive electrode, a material for forming the first electrode 122 may be indium tin oxide (“ITO”), indium zinc oxide (“IZO”), tin oxide (SnO2), zinc oxide (ZnO), or any combinations thereof. In some embodiments, when the first electrode 122 is a semi-transmissive electrode or a reflective electrode, magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combination thereof may be used as a material for forming the first electrode 122.
The first electrode 122 may have a single-layered structure consisting of a single layer or a multi-layered structure including two or more layers. In some embodiments, the first electrode 122 may have a triple-layered structure of ITO/Ag/ITO.
The interlayer 123 may be on the first electrode 122. The interlayer 123 may include an emission layer.
The interlayer 123 may further include a hole transport region between the first electrode 122 and the emission layer and an electron transport region between the emission layer and the second electrode 124.
The interlayer 123 may further include metal-containing compounds such as organometallic compounds, inorganic materials such as quantum dots, and the like, in addition to various organic materials.
The interlayer 123 may include: i) at least two emitting units sequentially stacked between the first electrode 122 and the second electrode 124; and ii) a charge generation layer located between the at least two emitting units. When the interlayer 123 includes the at least two emitting units and a charge generation layer, the light-emitting device 120 may be a tandem light-emitting device.
The hole transport region may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.
The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or a combination thereof.
In an embodiment, for example, the hole transport region may have a multi-layered structure, e.g., a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron blocking layer structure, wherein layers of each structure are sequentially stacked on the first electrode 122 in each stated order.
The hole transport region may include the compound represented by Formula 201, the compound represented by Formula 202, or any combination thereof:
In some embodiments, Formulae 201 and 202 may each include at least one of groups represented by Formulae CY201 to CY217:
wherein, in Formulae CY201 to CY217, R10b and R10c may each be understood by referring to the descriptions of R10a, ring CY201 to ring CY204 may each independently be a C3-C20 carbocyclic group or a C1-C20 heterocyclic group, and at least one hydrogen in Formulae CY201 to CY217 may be unsubstituted or substituted with R10a.
The thickness of the hole transport region may be in a range of about 50 Angstroms (Å) to about 10,000 Å, for example, about 100 Å to about 4,000 Å. When the hole transport region includes a hole injection layer, a hole transport layer, and any combination thereof, the thickness of the hole injection layer may be in a range of about 100 Å to about 9,000 Å, for example, about 100 Å to about 1,000 Å, the thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å, for example, about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within any of these ranges, excellent hole transport characteristics may be obtained without a substantial increase in driving voltage.
The emission auxiliary layer may increase light emission efficiency by compensating for an optical resonance distance according to the wavelength of light emitted by an emission layer. The electron blocking layer may prevent leakage of electrons to a hole transport region from the emission layer. Materials that may be included in the hole transport region may also be included in an emission auxiliary layer and an electron blocking layer.
<p-Dopant>
The hole transport region may include a charge generating material as well as the aforementioned materials to improve conductive properties of the hole transport region. The charge generating material may be substantially homogeneously or non-homogeneously dispersed (for example, as a single layer consisting of charge generating material) in the hole transport region.
The charge generating material may include, for example, a p-dopant.
In some embodiments, a lowest unoccupied molecular orbital (“LUMO”) energy level of the p-dopant may be −3.5 electron volts (eV) or less.
In some embodiments, the p-dopant may include a quinone derivative, a compound containing a cyano group, a compound containing element EL1 and element EL2, or any combination thereof.
Examples of the quinone derivative may include TCNQ, F4-TCNQ, and the like.
Examples of the compound containing a cyano group include HAT-CN, a compound represented by Formula 221, and the like:
In the compound containing element EL1 and element EL2, element EL1 may be a metal, a metalloid, or a combination thereof, and element EL2 may be non-metal, a metalloid, or a combination thereof.
When the light-emitting device 120 is a full color light-emitting device, the emission layer may be patterned into a red emission layer, a green emission layer, and/or a blue emission layer, according to a sub-pixel. In one or more embodiments, the emission layer may have a stacked structure. The stacked structure may include two or more layers selected from a red emission layer, a green emission layer, and a blue emission layer. The two or more layers may be in direct contact with each other. In some embodiments, the two or more layers may be separated from each other. In one or more embodiments, the emission layer may include two or more materials. The two or more materials may include a red light-emitting material, a green light-emitting material, or a blue light-emitting material. The two or more materials may be mixed with each other in a single layer. The two or more materials mixed with each other in the single layer may emit white light.
The emission layer may include a host and a dopant. The dopant may be a phosphorescent dopant, a fluorescent dopant, or any combination thereof.
The amount of the dopant in the emission layer may be in a range of about 0.01 parts to about 15 parts by weight based on 100 parts by weight of the host.
In some embodiments, the emission layer may include a quantum dot. The quantum dot may be understood by referring to the description of the quantum dot provided herein.
The emission layer may include a delayed fluorescence material. The delayed fluorescence material may serve as a host or a dopant in the emission layer.
The thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å, and in some embodiments, about 200 Å to about 600 Å. When the thickness of the emission layer is within any of these ranges, improved luminescence characteristics may be obtained without a substantial increase in driving voltage.
The host may include a compound represented by Formula 301:
[Ar301]xb11-[(L301)xb1-R301]xb21 Formula 301
In some embodiments, when xb11 in Formula 301 is 2 or greater, at least two Ar301(s) may be bound via a single bond.
In some embodiments, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:
The phosphorescent dopant may include at least one transition metal as a center metal.
The phosphorescent dopant may include a monodentate ligand, a bidentate ligand, a tridentate ligand, a tetradentate ligand, a pentadentate ligand, a hexadentate ligand, or any combination thereof.
The phosphorescent dopant may be electrically neutral.
In some embodiments, the phosphorescent dopant may include an organometallic complex represented by Formula 401:
In one or more embodiments, in Formula 402, i) X401 may be nitrogen, and X402 may be carbon, or ii) X401 and X402 may both be nitrogen.
In one or more embodiments, when xc1 in Formula 402 is 2 or greater, two ring A401(s) of at least two L401 (s) may optionally be bound via T402 as a linking group, or two ring A402(s) may optionally be bound via T403 as a linking group (see Compounds PD1 to PD4 and PD7). T402 and T403 may each be understood by referring to the description of T401 provided herein.
L402 in Formula 401 may be any suitable organic ligand. For example, L402 may be a halogen group, a diketone group (e.g., an acetylacetonate group), a carboxylic acid group (e.g., a picolinate group), —C(═O), an isonitrile group, —CN, or a phosphorus group (e.g., a phosphine group or a phosphite group).
The fluorescent dopant may include an amine group-containing compound, a styryl group-containing compound, or any combination thereof.
In some embodiments, the fluorescent dopant may include a compound represented by Formula 501:
In some embodiments, in Formula 501, Ar501 may include a condensed ring group (e.g., an anthracene group, a chrysene group, or a pyrene group) in which at least three monocyclic groups are condensed.
In some embodiments, xd4 in Formula 501 may be 2.
The emission layer may include a delayed fluorescence material.
The delayed fluorescence material described herein may be any suitable compound that may emit delayed fluorescence according to a delayed fluorescence emission mechanism.
The delayed fluorescence material included in the emission layer may serve as a host or a dopant, depending on types of other materials included in the emission layer.
In some embodiments, a difference between a triplet energy level (electron volts [eV]) of the delayed fluorescence material and a singlet energy level (eV) of the delayed fluorescence material may be about 0 eV or greater and about 0.5 eV or less. When the difference between a triplet energy level (eV) of the delayed fluorescence material and a singlet energy level (eV) of the delayed fluorescence material is within this range, up-conversion from a triplet state to a singlet state in the delayed fluorescence material may be effectively occurred, thus improving luminescence efficiency and the like of the light-emitting device 120.
In some embodiments, the delayed fluorescence material may include: i) a material including at least one electron donor (e.g., a π electron-rich C3-C60 cyclic group such as a carbazole group and the like) and at least one electron acceptor (e.g., a sulfoxide group, a cyano group, a π electron-deficient nitrogen-containing C1-C60 cyclic group, and the like), ii) a material including a C8-C60 polycyclic group including at least two cyclic groups condensed to each other and sharing boron (B), and the like.
The electron transport region may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.
The electron transport region may include a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or an electron injection layer.
In some embodiments, the electron transport region may have an electron transport layer/electron injection layer structure, a hole blocking layer/electron transport layer/electron injection layer structure, an electron control layer/electron transport layer/electron injection layer structure, or a buffer layer/electron transport layer/electron injection layer structure, wherein layers of each structure are sequentially stacked on the emission layer in each stated order.
The electron transport region (e.g., a buffer layer, a hole blocking layer, an electron control layer, or an electron transport layer in the electron transport region) may include a metal-free compound including at least one π electron-deficient nitrogen-containing C1-C60 cyclic group.
In some embodiments, the electron transport region may include a compound represented by Formula 601:
[Ar601]xe11-[(L601)xe1-R601]xe21 Formula 601
In some embodiments, when xe11 in Formula 601 is 2 or greater, at least two Ar601(s) may be bound via a single bond.
In some embodiments, in Formula 601, Ar601 may be a substituted or unsubstituted anthracene group.
In some embodiments, the electron transport region may include a compound represented by Formula 601-1:
In an embodiment, for example, in Formulae 601 and 601-1, xe1 and xe611 to xe613 may each independently be 0, 1, or 2.
The thickness of the electron transport region may be in a range of about 100 Angstroms (Å) to about 5,000 Å, for example, about 160 Å to about 4,000 Å. When the electron transport region includes a buffer layer, a hole blocking layer, an electron control layer, an electron transport layer, or any combination thereof, the thicknesses of the buffer layer, the hole blocking layer, or the electron control layer may each independently be in a range of about 20 Å to about 1,000 Å, for example, about 30 Å to about 300 Å, and the thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thicknesses of the buffer layer, the hole blocking layer, the electron control layer, the electron transport layer, and/or the electron transport layer are each within these ranges, excellent electron transport characteristics may be obtained without a substantial increase in driving voltage.
The electron transport region (for example, the electron transport layer in the electron transport region) may further include, in addition to the materials described above, a metal-containing material.
The metal-containing material may include an alkali metal complex, an alkaline earth metal complex, or any combination thereof. A metal ion of the alkali metal complex may be a lithium (Li) ion, a sodium (Na) ion, a potassium (K) ion, a rubidium (Rb) ion, or a cesium (Cs) ion. A metal ion of the alkaline earth metal complex may be a beryllium (Be) ion, a magnesium (Mg) ion, a calcium (Ca) ion, a strontium (Sr) ion, or a barium (Ba) ion. Each ligand coordinated with the metal ion of the alkali metal complex and the alkaline earth metal complex may independently be hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof.
In an embodiment, for example, the metal-containing material may include a Li complex. The Li complex may include, e.g., Compound ET-D1 (LiQ) or Compound ET-D2:
The electron transport region may include an electron injection layer that facilitates injection of electrons from the second electrode 124. The electron injection layer may be in direct contact with the second electrode 124.
The electron injection layer may have i) a single-layered structure consisting of a single layer consisting of a single material, ii) a single-layered structure consisting of a single layer including a plurality of different materials, or iii) a multi-layered structure having a plurality of layers including a plurality of different materials.
The electron injection layer may include an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof.
The alkali metal may be Li, Na, K, Rb, Cs or any combination thereof. The alkaline earth metal may be Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may be Sc, Y, Ce, Tb, Yb, Gd, or any combination thereof.
The alkali metal-containing compound, the alkaline earth metal-containing compound, and the rare earth metal-containing compound may be oxides, halides (e.g., fluorides, chlorides, bromides, or iodides), tellurides, or any combination thereof of each of the alkali metal, the alkaline earth metal, and the rare earth metal, respectively.
The alkali metal-containing compound may be alkali metal oxides such as Li2O, Cs2O, or K2O, alkali metal halides such as LiF, NaF, CsF, KF, LiI, NaI, CsI, or Kl, or any combination thereof. The alkaline earth-metal-containing compound may include alkaline earth-metal oxides, such as BaO, SrO, CaO, BaxSr1-xO (wherein x is a real number satisfying 0<x<1), or BaxCa1-xO (wherein x is a real number satisfying 0<x<1). The rare earth metal-containing compound may include YbF3, ScF3, Sc2O3, Y2O3, Ce2O3, GdF3, TbF3, YbI3, ScI3, TbI3, or any combination thereof. In some embodiments, the rare earth metal-containing compound may include a lanthanide metal telluride. Examples of the lanthanide metal telluride may include LaTe, CeTe, PrTe, NdTe, PmTe, SmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, La2Te3, Ce2Te3, Pr2Te3, Nd2Te3, Pm2Te3, Sm2Te3, Eu2Te3, Gd2Te3, Tb2Te3, Dy2Te3, Ho2Te3, Er2Te3, Tm2Te3, Yb2Te3, Lu2Te3, and the like.
The alkali metal complex, the alkaline earth metal complex, and the rare earth metal complex may include: i) one of ions of the alkali metal, alkaline earth metal, and rare earth metal described above and ii) a ligand bond to the metal ion, e.g., hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenylbenzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or any combination thereof.
The electron injection layer may consist of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof, as described above. In some embodiments, the electron injection layer may further include an organic material (e.g., a compound represented by Formula 601).
In some embodiments, the electron injection layer may consist of i) an alkali metal-containing compound (e.g., alkali metal halide), or ii) a) an alkali metal-containing compound (e.g., alkali metal halide); and b) an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. In some embodiments, the electron injection layer may be a Kl:Yb co-deposition layer, a RbI:Yb co-deposition layer, or the like.
When the electron injection layer further includes an organic material, the alkali metal, the alkaline earth metal, the rare earth metal, the alkali metal-containing compound, the alkaline earth metal-containing compound, the rare earth metal-containing compound, the alkali metal complex, the alkaline earth metal complex, the rare earth metal complex, or any combination thereof may be homogeneously or non-homogeneously dispersed in a matrix including the organic material.
The thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å, and in some embodiments, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within any of these ranges, excellent electron injection characteristics may be obtained without a substantial increase in driving voltage.
The second electrode 124 may be on the interlayer 123. In an embodiment, the second electrode 124 may be a cathode that is an electron injection electrode. In this embodiment, a material for forming the second electrode 124 may be a material having a low work function, for example, a metal, an alloy, an electrically conductive compound, or any combination thereof.
The second electrode 124 may include lithium (Li), silver (Ag), magnesium (Mg), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), ytterbium (Yb), silver-ytterbium (Ag—Yb), ITO, IZO, or any combination thereof. The second electrode 124 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode.
The second electrode 124 may have a single-layered structure, or a multi-layered structure including two or more layers.
A first capping layer may be located outside the first electrode 122, and/or a second capping layer may be located outside the second electrode 124. In some embodiments, the light-emitting device 120 may have a structure in which the first capping layer, the first electrode 122, the interlayer 123, and the second electrode 124 are sequentially stacked in this stated order, a structure in which the first electrode 122, the interlayer 123, the second electrode 124, and the second capping layer are sequentially stacked in this stated order, or a structure in which the first capping layer, the first electrode 122, the interlayer 123, the second electrode 124, and the second capping layer are sequentially stacked in this stated order.
In the light-emitting device 120, light emitted from the emission layer in the interlayer 123 may pass through the first electrode 122 (which may be a semi-transmissive electrode or a transmissive electrode) and through the first capping layer to the outside. In the light-emitting device 120, light emitted from the emission layer in the interlayer 123 may pass through the second electrode 124 (which may be a semi-transmissive electrode or a transmissive electrode) and through the second capping layer to the outside.
The first capping layer and the second capping layer may improve the external luminescence efficiency based on the principle of constructive interference. Accordingly, the optical extraction efficiency of the light-emitting device 120 may be increased, thus improving the luminescence efficiency of the light-emitting device 120.
The first capping layer and the second capping layer may each include a material having a refractive index of 1.6 or higher (at 589 nm).
The first capping layer and the second capping layer may each independently be a capping layer including an organic material, an inorganic capping layer including an inorganic material, or a composite capping layer including an organic material and an inorganic material.
At least one of the first capping layer and the second capping layer may each independently include carbocyclic compounds, heterocyclic compounds, amine group-containing compounds, porphine derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, alkali metal complexes, alkaline earth metal complexes, or any combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may optionally be substituted with a substituent of O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. In some embodiments, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound.
In some embodiments, at least one of the first capping layer and the second capping layer may each independently include the compound represented by Formula 201, the compound represented by Formula 202, or any combination thereof.
The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may be formed in a specific region by using one or more suitable methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (“LB”) deposition, ink-jet printing, laser printing, and laser-induced thermal imaging.
When layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region are each independently formed by vacuum-deposition, the vacuum-deposition may be performed at a deposition temperature in a range of about 100° C. to about 500° C., at a vacuum degree in a range of about 10−8 torr to about 10−3 torr, and at a deposition rate in a range of about 0.01 Angstroms per second (A/sec) to about 100 Å/sec, depending on the material to be included in each layer and the structure of each layer to be formed.
When layers constituting the hole transport region, the emission layer, and layers constituting the electron transport region are each independently formed by spin coating, the spin coating may be performed at a coating rate of about 2,000 revolutions per minute (rpm) to about 5,000 rpm and at a heat treatment temperature of about 80° C. to 200° C., depending on the material to be included in each layer and the structure of each layer to be formed.
The term “C3-C60 carbocyclic group” as used herein refers to a cyclic group consisting of carbon atoms only and having 3 to 60 carbon atoms as ring-forming atoms. The term “C1-C60 heterocyclic group” as used herein refers to a cyclic group having 1 to 60 carbon atoms in addition to a heteroatom as ring-forming atoms other than carbon atoms. The C3-C60 carbocyclic group and the C1-C60 heterocyclic group may each be a monocyclic group consisting of one ring or a polycyclic group in which at least two rings are condensed. For example, the number of ring-forming atoms in the C1-C60 heterocyclic group may be in a range of 3 to 61.
The term “cyclic group” as used herein may include the C3-C60 carbocyclic group and the C1-C60 heterocyclic group.
The term “T1 electron-rich C3-C60 cyclic group” refers to a cyclic group having 3 to 60 carbon atoms and not including *—N=*′ as a ring-forming moiety. The term “T1 electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein refers to a heterocyclic group having 1 to 60 carbon atoms and *—N=*′ as a ring-forming moiety.
In some embodiments,
The term “cyclic group”, “C3-C60 carbocyclic group”, “C1-C60 heterocyclic group”, “π electron-rich C3-C60 cyclic group”, or “π electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein may be a group condensed with any suitable cyclic group, a monovalent group, or a polyvalent group (e.g., a divalent group, a trivalent group, a quadvalent group, or the like), depending on the structure of the formula to which the term is applied. For example, a “benzene group” may be a benzene ring, a phenyl group, a phenylene group, or the like, and this may be understood by one of ordinary skill in the art, depending on the structure of the formula including the “benzene group”.
Examples of the monovalent C3-C60 carbocyclic group and the monovalent C1-C60 heterocyclic group may include a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group. Examples of the divalent C3-C60 carbocyclic group and the divalent C1-C60 heterocyclic group may include a C3-C10 cycloalkylene group, a C1-C10 heterocycloalkylene group, a C3-C10 cycloalkenylene group, a C1-C10 heterocycloalkenylene group, a C6-C60 arylene group, a C1-C60 heteroarylene group, a divalent non-aromatic condensed polycyclic group, and a divalent non-aromatic condensed heteropolycyclic group.
The term “C1-C60 alkyl group” as used herein refers to a linear or branched aliphatic hydrocarbon monovalent group having 1 to 60 carbon atoms, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an iso-nonyl group, a sec-nonyl group, a tert-nonyl group, an n-decyl group, an isodecyl group, a sec-decyl group, and a tert-decyl group. The term “C1-C60 alkylene group” as used herein refers to a divalent group having the same structure as the C1-C60 alkyl group.
The term “C2-C60 alkenyl group” as used herein refers to a hydrocarbon group having at least one carbon-carbon double bond in the middle or at the terminus of the C2-C60 alkyl group. Examples thereof include an ethenyl group, a propenyl group, and a butenyl group. The term “C2-C60 alkenylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkenyl group.
The term “C2-C60 alkynyl group” as used herein refers to a monovalent hydrocarbon group having at least one carbon-carbon triple bond in the middle or at the terminus of the C2-C60 alkyl group. Examples thereof include an ethynyl group and a propynyl group. The term “C2-C60 alkynylene group” as used herein refers to a divalent group having the same structure as the C2-C60 alkynyl group.
The term “C1-C60 alkoxy group” as used herein refers to a monovalent group represented by —OA101 (wherein A101 is a C1-C1 alkyl group). Examples thereof include a methoxy group, an ethoxy group, and an isopropyloxy group.
The term “C3-C10 cycloalkyl group” as used herein refers to a monovalent saturated hydrocarbon monocyclic group including 3 to 10 carbon atoms. Examples of the C3-C10 cycloalkyl group as used herein include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl (bicyclo[2.2.1]heptyl) group, a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, or a bicyclo[2.2.2]octyl group. The term “C3-C10 cycloalkylene group” as used herein refers to a divalent group having the same structure as the C3-C10 cycloalkyl group.
The term “C1-C10 heterocycloalkyl group” as used herein refers to a monovalent cyclic group including at least one heteroatom other than carbon atoms as a ring-forming atom and having 1 to 10 carbon atoms. Examples thereof include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, and a tetrahydrothiophenyl group. The term “C1-C10 heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C1-C10 heterocycloalkyl group.
The term “C3-C10 cycloalkenyl group” as used herein refers to a monovalent cyclic group that has 3 to 10 carbon atoms and at least one carbon-carbon double bond in its ring, and is not aromatic. Examples thereof include a cyclopentenyl group, a cyclohexenyl group, and a cycloheptenyl group. The term “C3-C10 cycloalkenylene group” as used herein refers to a divalent group having the same structure as the C3-C10 cycloalkenyl group.
The term “C1-C10 heterocycloalkenyl group” as used herein refers to a monovalent cyclic group including at least one heteroatom other than carbon atoms as a ring-forming atom, 1 to 10 carbon atoms, and at least one double bond in its ring. Examples of the heterocycloalkenyl group include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, and a 2,3-dihydrothiophenyl group. The term “C1-C10 heterocycloalkylene group” as used herein refers to a divalent group having the same structure as the C1-C10 heterocycloalkyl group.
The term “C6-C60 aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. The term “C6-C60 arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having 6 to 60 carbon atoms. Examples of the C6-C60 aryl group include a phenyl group, a pentalenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a heptalenyl group, a naphthacenyl group, a picenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, and an ovalenyl group. When the C6-C60 aryl group and the C6-C60 arylene group each independently include two or more rings, the respective rings may be fused.
The term “C1-C60 heteroaryl group” as used herein refers to a monovalent group having a heterocyclic aromatic system further including at least one heteroatom other than carbon atoms as a ring-forming atom and 1 to 60 carbon atoms. The term “C1-C60 heteroarylene group” as used herein refers to a divalent group having a heterocyclic aromatic system further including at least one heteroatom other than carbon atoms as a ring-forming atom and 1 to 60 carbon atoms. Examples of the C1-C60 heteroaryl group include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a benzoisoquinolinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a phthalazinyl group, and a naphthyridinyl group. When the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each independently include two or more rings, the respective rings may be fused.
The term “monovalent non-aromatic condensed polycyclic group” as used herein refers to a monovalent group that has two or more condensed rings and only carbon atoms (e.g., 8 to 60 carbon atoms) as ring forming atoms, wherein the molecular structure when considered as a whole is non-aromatic. Examples of the monovalent non-aromatic condensed polycyclic group include an indenyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, and an indenoanthracenyl group. The term “divalent non-aromatic condensed polycyclic group” as used herein refers to a divalent group having substantially the same structure as the monovalent non-aromatic condensed polycyclic group.
The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein refers to a monovalent group that has two or more condensed rings and at least one heteroatom other than carbon atoms (e.g., 1 to 60 carbon atoms), as a ring-forming atom, wherein the molecular structure when considered as a whole is non-aromatic. Examples of the monovalent non-aromatic condensed heteropolycyclic group include a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, a naphthoindolyl group, an isoindolyl group, a benzoisoindolyl group, a naphthoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, a dibenzofuranyl group, an azacarbazolyl group, an azafluorenyl group, an azadibenzosilolyl group, an azadibenzothiophenyl group, an azadibenzofuranyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzopyrazolyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a benzooxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indenocarbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a benzosilolocarbazolyl group, a benzoindolocarbazolyl group, a benzocarbazolyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a benzonaphthosilolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein refers to a divalent group having substantially the same structure as the monovalent non-aromatic condensed heteropolycyclic group.
The term “C6-C60 aryloxy group” as used herein is represented by —OA102 (wherein A102 is the C6-C60 aryl group). The term “C6-C60 arylthio group” as used herein is represented by —SA103 (wherein A103 is the C6-C60 aryl group).
The term “C7-C60 aryl alkyl group” used herein refers to -A104A105 (where A104 may be a C1-C54 alkylene group, and A105 may be a C6-C59 aryl group), and the term “C2-C60 heteroaryl alkyl group” used herein refers to -A106A107 (where A106 may be a C1-C59 alkylene group, and A107 may be a C1-C59 heteroaryl group).
The term “R10a” as used herein may be:
The term “heteroatom” as used herein refers to any atom other than a carbon atom. Examples of the heteroatom may include O, S, N, P, Si, B, Ge, Se, or any combination thereof.
A third-row transition metal as used herein may include hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), or gold (Au).
“Ph” used herein represents a phenyl group, “Me” used herein represents a methyl group, “Et” used herein represents an ethyl group, “ter-Bu” or “But” used herein represents a tert-butyl group, and “OMe” used herein represents a methoxy group.
The term “biphenyl group” as used herein refers to a phenyl group substituted with a phenyl group. The “biphenyl group” belongs to a substituted phenyl group having a C6-C60 aryl group as a substituent.
The term “terphenyl group” as used herein refers to a phenyl group substituted with a biphenyl group. The “terphenyl group” belongs to “a substituted phenyl group” having a “C6-C60 aryl group substituted with a C6-C60 aryl group” as a substituent.
The number of maximum carbon atoms in the definitions are illustrative only. For example, the number of maximum carbon atoms in the C1-C60 alkyl group of 60 may be exemplary and also be applied to the C1-C20 alkyl group. Other cases may also be the same.
The symbols * and *′ as used herein, unless defined otherwise, refer to a binding site to an adjacent atom in a corresponding formula.
Hereinafter, with reference to the Examples, the manufacture and evaluation of the display apparatus including the light-emitting apparatus will be described in detail.
100 wt % of 1,6-hexanedilo diacrylate as a monomer, 100 wt % of Ag—In—Ga—S for green quantum dots based on 100 wt % of monomer, 10 wt % of scatterer TiO2 based on 100 wt % of monomer, 0.1 wt % of initiator TPO based on 100 wt % of monomer, and 2 wt % of dispersant (—[CH2—CH(COONa)—]m/molecular weight in a range of 500 to 15,000) based on 100 wt % of monomer were mixed to prepare a green quantum dot ink composition.
100 wt % of 1,6-hexanedilo diacrylate as a monomer, 100 wt % of Ag—In—Ga—S for red quantum dots based on 100 wt % of monomer, 10 wt % of scatterer TiO2 based on 100 wt % of monomer, 0.1 wt % of initiator TPO based on 100 wt % of monomer, and 2 wt % of dispersant (—[CH2—CH(COONa)—]m/molecular weight in a range of 500 to 15,000) based on 100 wt % of monomer were mixed to prepare a red quantum dot ink composition.
The Ag—In—Ga—S for green quantum dots and the Ag—In—Ga—S for red quantum dots have the same component but a different core size.
100 wt % of 1,6-hexanedilo diacrylate as a monomer, 20 wt % of scatterer TiO2 based on 100 wt % of monomer, 0.1 wt % of initiator TPO based on 100 wt % of monomer, and 2 wt % of dispersant (—[CH2—CH(COONa)—]m/molecular weight in a range of 500 to 15,000) based on 100 wt % of monomer were mixed to prepare a scatterer ink composition.
An organic capping layer ink composition was prepared in the same manner as in Preparation of green quantum dot ink composition, except that the Ag—In—Ga—S for green quantum dots and the scatterer TiO2 were omitted.
As shown in
Next, as shown in
Next, as shown in
Subsequently, as shown in
Subsequently, the organic capping layer 400 was formed by using the organic capping layer ink composition by an inkjet process on the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W. More details of the process are as follows.
The organic capping layer 400 was formed again with inkjet on the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W formed with inkjet, and then UV (390 nm) was irradiated for 50 seconds to cure the quantum dot layer 230R, the quantum dot layer 230G, the scattering Layer 230W, and the organic capping layer 400 simultaneously. Next, the quantum dot layer 230R, the quantum dot layer 230G, the scattering layer 230W, and the organic capping layer 400 were post-baked at 100 degrees in Celsius (° C.) for 10 minutes in an atmospheric atmosphere. The thickness of the organic capping layer 400 was 5 μm.
Next, silicon nitride was vapor-deposited to form the inorganic capping layer 270 having a thickness of 1,000 Å.
Next, as shown in
A display apparatus was manufactured in the same manner as in Example 1, except that the organic capping layer 400 was not formed on the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W, UV (390 nm) was irradiated for 50 seconds to cure the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W, the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W were post-baked at 100° C. for 10 minutes in an atmospheric atmosphere, and silicon nitride was vapor-deposited in an atmospheric atmosphere to form the inorganic capping layer 270 having a thickness of 1,000 Å.
A display apparatus was manufactured in the same manner as in Example 1, except that the organic capping layer 400 was not formed on the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W, UV (390 nm) was irradiated for 50 seconds to cure the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W, the quantum dot layer 230R, the quantum dot layer 230G, and the scattering layer 230W were moved to the N2 atmosphere line and post-baked at 100° C. for 10 minutes in an N2 atmosphere, and silicon nitride was vapor-deposited in an N2 atmosphere to form the inorganic capping layer 270 having a thickness of 1,000 Å.
The light emission patterns of the display apparatuses of Example 1 and Comparative Examples 1 and 2 are shown in
As shown in
However, the display apparatus of Comparative Example 1 showed a significant decrease in peak intensity and an increase in peak intensity at an unwanted long wavelength, as compared with the display apparatus of Example 1. This may result from a defect occurred in the quantum dot layer due to penetration of moisture and oxygen while forming the inorganic capping layer 270 under atmospheric conditions.
As apparent from the foregoing description, a quantum dot layer of a display apparatus may be protected from penetration of moisture and oxygen, and thus, for example, an N2 atmosphere inline process is not required.
It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0028933 | Mar 2022 | KR | national |
