Patent Application
20220376184
This application claims priority from and the benefit of Korean Patent Application No. 10-2021-0056770, filed on Apr. 30, 2021, which is hereby incorporated by reference for all purposes as if fully set forth herein.
Embodiments of the invention relate generally to display devices and, more particularly, to a light-emitting device and an electronic apparatus including the same.
Light-emitting devices are self-emissive devices that, as compared with devices of is the related art, have wide viewing angles, high contrast ratios, short response times, and excellent characteristics in terms of luminance, driving voltage, and response speed.
Light-emitting devices may have a structure in which a first electrode is located on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode are sequentially formed on the first electrode. Holes provided from the first electrode move toward the emission layer through the hole transport region, and electrons provided from the second electrode move toward the emission layer through the electron transport region. Carriers such as holes and electrons recombine in the emission layer to produce light.
The above information disclosed in this Background section is only for understanding of the background of the inventive concepts, and, therefore, it may contain information that does not constitute prior art.
Light-emitting devices constructed according to illustrative implementations of the invention and electronic apparatuses including the same have reduced driving voltage, improved efficiency, and increased lifespan, as compared with the related art.
More specifically, when indium tin oxide (ITO) electrodes are used in light emitting devices in the related art, their work function is insufficient to facilitate the supply of holes. To overcome this problem, plasma treatment of an electrode, or a hole injection layer to which a p-dopant (for example, a CN-containing compound) is added has been attempted. In addition, when a p-dopant is not used and an electrode material with a deeper work function is used, the interface between the electrode and the hole transport layer may become unstable, causing an undesirable reduction in lifespan.
Applicant discovered that by incorporating a metal oxide having a work function is value of about −5.3 eV or less into the first electrode of a light emitting device, and when the layer including the compound represented by Formula 1 described herein is incorporated into the interlayer, hole injection is facilitated without using a p-dopant, thereby obviating the interfacial instability problem of the electrode-hole transport layer.
Additional features of the inventive concepts will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the inventive concepts.
According to one aspect of the invention, a light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer between the first electrode and the second electrode and including an emission layer, wherein the first electrode includes a metal oxide having a work function value of about −5.3 eV or less, and the interlayer includes a layer including a compound of Formula 1:
wherein, in Formula 1, the variables are described herein.
The first electrode may include an anode, the second electrode may include a cathode, and the interlayer may further include an electron transport region including a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.
The metal of the metal oxide may be molybdenum, tungsten, copper, nickel, vanadium, or any combination thereof.
The group A1 may be a naphthalene moiety.
The layer including the compound of Formula 1 may include a hole transport layer.
The layer including the compound of Formula 1 and the first electrode may be in contact with each other.
The interlayer may exclude a p-dopant.
The metal oxide may include MoO3, MoO2, WO3, WO2, WO, W2O3, W2O5, Cu2O, CuO, Cu2O3, NiO, Ni2O3, Ni2O, VO, VO2, V2O3, V2O5, V6O13, or any combination thereof.
The groups Ar1, Ar3, and Ar4 may each be, independently from one another, a C6-C60 aryl group unsubstituted or substituted at least one R10a, and the group Ar2 may be a C1-C60 heteroaryl group unsubstituted or substituted with at least one R10a or a C6-C60 aryl group unsubstituted or substituted with at least one R10a.
The variables R1 to R3 may each be, independently from one another, hydrogen or deuterium.
The variable L1 may be a single bond.
The groups Ar1 to Ar4 may each be, independently from one another, one of Formulae 2a to 2d:
wherein, in Formulae 2a to 2d, the variables are described herein.
The compound of Formula 1 may be of Formula 2:
wherein, in Formula 2, the variables are described herein.
The compound of Formula 1 may be of Formula 3:
wherein, in Formula 3, the variables are described herein.
The compound of Formula 1 may be of Formula 4:
wherein, in Formula 4, the variables are described herein.
The compound of Formula 1 may be one of the Compounds 1-42, as depicted herein.
An electronic apparatus may include the light-emitting device as described above.
The electronic apparatus may further include a thin-film transistor, wherein the thin-film transistor includes a source electrode and a drain electrode, and the first electrode of the light-emitting device may be electrically connected to at least one of the source electrode and the drain electrode of the thin-film transistor.
The electronic apparatus may further include a color filter, a color conversion layer, a touch screen layer, a polarizing layer, or any combination thereof.
Another aspect of the invention is a compound of Formula 1:
wherein, in Formula 1, the variables are described herein.
It is to be understood that both the foregoing general description and the following detailed description are illustrative and explanatory and are intended to provide further explanation of the invention as claimed.
The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate illustrative embodiments of the invention, and together with the description serve to explain the inventive concepts.
In the following description, for the purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of various embodiments or implementations of the invention. As used herein “embodiments” and “implementations” are interchangeable words that are non-limiting examples of devices or methods employing one or more of the inventive concepts disclosed herein. It is apparent, however, that various embodiments may be practiced without these specific details or with one or more equivalent arrangements. In other instances, well-known structures and devices are shown in block diagram form in order to avoid unnecessarily obscuring various embodiments. Further, various embodiments may be different, but do not have to be exclusive. For example, specific shapes, configurations, and characteristics of an embodiment may be used or implemented in another embodiment without departing from the inventive concepts.
Unless otherwise specified, the illustrated embodiments are to be understood as is providing illustrative features of varying detail of some ways in which the inventive concepts may be implemented in practice. Therefore, unless otherwise specified, the features, components, modules, layers, films, panels, regions, and/or aspects, etc. (hereinafter individually or collectively referred to as “elements”), of the various embodiments may be otherwise combined, separated, interchanged, and/or rearranged without departing from the inventive concepts.
The use of cross-hatching and/or shading in the accompanying drawings is generally provided to clarify boundaries between adjacent elements. As such, neither the presence nor the absence of cross-hatching or shading conveys or indicates any preference or requirement for particular materials, material properties, dimensions, proportions, commonalities between illustrated elements, and/or any other characteristic, attribute, property, etc., of the elements, unless specified. Further, in the accompanying drawings, the size and relative sizes of elements may be exaggerated for clarity and/or descriptive purposes. When an embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order. Also, like reference numerals denote like elements, and duplicative explanations are omitted to avoid redundancy.
When an element, such as a layer, is referred to as being “on,” “connected to,” or “coupled to” another element or layer, it may be directly on, connected to, or coupled to the other element or layer or intervening elements or layers may be present. When, however, an element or layer is referred to as being “directly on,” “directly connected to,” or “directly coupled to” another element or layer, there are no intervening elements or layers present. To this end, the term “connected” may refer to physical, electrical, and/or fluid connection, with or without is intervening elements. Further, the D1-axis, the D2-axis, and the D3-axis are not limited to three axes of a rectangular coordinate system, such as the x, y, and z—axes, and may be interpreted in a broader sense. For example, the D1-axis, the D2-axis, and the D3-axis may be perpendicular to one another, or may represent different directions that are not perpendicular to one another. For the purposes of this disclosure, “at least one of X, Y, and Z” and “at least one selected from the group consisting of X, Y, and Z” may be construed as X only, Y only, Z only, or any combination of two or more of X, Y, and Z, such as, for instance, XYZ, XYY, YZ, and ZZ. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.
Although the terms “first,” “second,” etc. may be used herein to describe various types of elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another element. Thus, a first element discussed below could be termed a second element without departing from the teachings of the disclosure.
Spatially relative terms, such as “beneath,” “below,” “under,” “lower,” “above,” “upper,” “over,” “higher,” “side” (e.g., as in “sidewall”), and the like, may be used herein for descriptive purposes, and, thereby, to describe one elements relationship to another element(s) as illustrated in the drawings. Spatially relative terms are intended to encompass different orientations of an apparatus in use, operation, and/or manufacture in addition to the orientation depicted in the drawings. For example, if the apparatus in the drawings is turned over, elements described as “below” or “beneath” other elements or features would then be oriented “above” the other elements or features. Thus, the term “below” can encompass both an orientation of above and below. Furthermore, the apparatus may be otherwise oriented (e.g., rotated 90 degrees or at other orientations), and, as such, the spatially relative descriptors used herein interpreted is accordingly.
The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting. As used herein, the singular forms, “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. Moreover, the terms “comprises,” “comprising,” “includes,” and/or “including,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, components, and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It is also noted that, as used herein, the terms “substantially,” “about,” and other similar terms, are used as terms of approximation and not as terms of degree, and, as such, are utilized to account for inherent deviations in measured, calculated, and/or provided values that would be recognized by one of ordinary skill in the art.
Various embodiments are described herein with reference to sectional and/or exploded illustrations that are schematic illustrations of idealized embodiments and/or intermediate structures. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments disclosed herein should not necessarily be construed as limited to the particular illustrated shapes of regions, but are to include deviations in shapes that result from, for instance, manufacturing. In this manner, regions illustrated in the drawings may be schematic in nature and the shapes of these regions may not reflect actual shapes of regions of a device and, as such, are not necessarily intended to be limiting.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to is which this disclosure is a part. Terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense, unless expressly so defined herein.
An indium tin oxide (ITO) electrode according to the related art has a work function value of −4.8 eV, which is insufficient to facilitate the supply of holes. To overcome the problems, plasma treatment of an electrode, or a hole injection layer to which a p-dopant (for example, a CN-containing compound) is added has been introduced. In addition, when a p-dopant is not used and an electrode material with a deeper work function is used, the interface between the electrode and the hole transport layer may become unstable, causing an undesirable reduction in lifespan.
According to one aspect of the invention, a light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an interlayer interposed between the first electrode and the second electrode and including an emission layer, wherein the first electrode includes a metal oxide having a work function value of about −5.3 eV or less, and the interlayer includes a layer including a compound represented by Formula 1:
wherein, in Formula 1,
A1 may be a bicyclic aromatic moiety unsubstituted or substituted with at least one R10a,
Ar1 to Ar4, and R1 to R3 may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group is unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkynyl group unsubstituted or substituted with at least one R10a, a C1-C60 alkoxy group unsubstituted or substituted with at least one R10a, a C3-C10 cycloalkyl group unsubstituted or substituted with at least one R10a, a C1-C10 heterocycloalkyl group unsubstituted or substituted with at least one R10a, a C3-C10 cycloalkenyl group unsubstituted or substituted with at least one R10a, a C1-C10 heterocycloalkenyl group unsubstituted or substituted with at least one R10a, a C6-C60 aryl group unsubstituted or substituted with at least one R10a, a C6-C60 aryloxy group unsubstituted or substituted with at least one R10a, a C6-C60 arylthio group unsubstituted or substituted with at least one R10a, a C1-C60 heteroaryl group unsubstituted or substituted with at least one R10a, a C8-C60 monovalent non-aromatic condensed polycyclic group unsubstituted or substituted with at least one R10a, a C1-C60 monovalent non-aromatic condensed heteropolycyclic group unsubstituted or substituted with at least one R10a, —Si(Q1)(Q2)(Q3), —B(Q1)(Q2), —N(Q1)(Q2), —P(Q1)(Q2), —C(═O)(Q1), —S(═O)(Q1), —S(═O)2(Q1), —P(═O)(Q1)(Q2), and —P(═S)(Q1)(Q2),
L1 may be selected from among a single bond, a C6-C60 arylene group unsubstituted or substituted with at least one R10a, and C1-C60 heteroarylene group unsubstituted or substituted with at least one R10a,
m may be an integer from 1 to 3,
a1 may be an integer from 1 to 4,
a2 and a3 may each independently be an integer from 1 to 3, and
R10a may be:
deuterium (—D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group;
a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, or a C1-C60 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C7-C60 aryl alkyl group, a C2-C60 heteroaryl alkyl group, —Si(Q11)(Q12)(Q13), —N(Q11)(Q12), —B(Q11)(Q12), —C(═O)(Q11), —S(═O)2(Q11), —P(═O)(Q11)(Q12), or any combination thereof;
a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C7-C60 aryl alkyl group, or a C2-C60 heteroaryl alkyl group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C7-C60 aryl alkyl group, a C2-C60 heteroaryl alkyl group, —Si(Q21)(Q22)(Q23), —N(Q21)(Q22), —B(Q21)(Q22), —C(═O)(Q21), —S(═O)2(Q21), —P(═O)(Q21)(Q22), or any combination thereof; or
—Si(Q31)(Q32)(Q33), —N(Q31)(Q32), —B(Q31)(Q32), —C(═O)(Q31), —S(═O)2(Q31), or —P(═O)(Q31)(Q32),
wherein Q1 to Q3, Q11 to Q13, Q21 to Q23, and Q31 to Q33 may each independently be: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C1-C60 alkyl group; a C2-C60 alkenyl group; a C2-C60 alkynyl group; a C1-C60 alkoxy group; a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C7-C60 aryl alkyl group or a C2-C60 heteroaryl alkyl group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C1-C60 alkyl group, a C1-C60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.
By incorporating the metal oxide having a work function value of −5.3 eV or less into the first electrode, and the layer including the compound represented by Formula 1 into the interlayer, hole injection has been facilitated without using a p-dopant, thereby obviating the interfacial instability problem caused by the electrode-hole transport layer.
In one or more embodiments, the first electrode may be an anode, the second electrode may be a cathode, and the interlayer may further include an electron transport region including a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.
In one or more embodiments, a metal of the metal oxide may be molybdenum (Mo), tungsten (W), copper (Cu), nickel (Ni), vanadium (V), or any combination thereof. The any combination thereof may include, for example, an alloy of tungsten and molybdenum; an alloy of copper and tungsten; an alloy of tungsten and copper; an alloy of tungsten and nickel; an alloy of tungsten and vanadium; an alloy of tungsten, molybdenum, and copper; an alloy of nickel and vanadium, and the like.
In Formula 1, A1 may be a bicyclic aromatic moiety, and A1 may be substituted with at least one R10a. The bicyclic aromatic moiety refers to a moiety consisting of two rings and satisfying 4n+2 rule (wherein n is 0 or natural number). Non-limiting examples of the bicyclic aromatic moiety are a quinoline, a quinazoline, a benzotriazine, and naphthalene. In one or more embodiments, A1 may be a naphthalene moiety. In one or more embodiments, the layer including the compound represented by Formula 1 may be a hole transport layer.
In one or more embodiments, the layer including the compound represented by Formula 1 and the first electrode may be in contact with each other. For example, the layer including the compound represented by Formula 1 may be a hole transport layer, and the hole transport layer including the compound represented by Formula 1 may be in contact with each other. The expression “contact each other” or “in contact” refers to direct physical contact. Accordingly, the light-emitting device according to an embodiment may not include a hole injection layer. The light-emitting device according to an embodiment may not include a layer including a p-dopant. In one or more embodiments, the interlayer may not include a p-dopant.
In the light-emitting device according to an embodiment, when the first electrode includes a metal oxide having a work function value of about −5.3 eV or less, the layer including the compound represented by Formula 1 is a hole transport layer, and the hole transport layer including the compound represented by Formula 1 and the first electrode are in contact, hole injection may be facilitated without plasma treatment of the first electrode or using a p-dopant, the interface between first electrode and the hole transport layer may be stabilized, consequently reducing the driving voltage of the device and improving lifespan of the device.
In one or more embodiments, the metal oxide may include MoO3, MoO2, WO3, WO2, WO, W203, W2O5, Cu2O, CuO, Cu2O3, NiO, Ni2O3, Ni2O, VO, VO2, V2O3, V2O5, V6O13, or any combination thereof. For example, the metal oxide may consist of MoO3, MoO2, WO3, WO2, WO, W2O3, W2O5, Cu2O, CuO, Cu2O3, NiO, Ni2O3, Ni2O, VO, VO2, V2O3, V2O5, V6O13, or any combination thereof. For example, the first electrode may consist of MoO3, MoO2, WO3, WO2, WO, W2O3, W2O5, Cu2O, CuO, Cu2O3, NiO, Ni2O3, Ni2O, VO, VO2, VO2O3, V2O5, V6O13, or any combination thereof. In one or more embodiments, in Formula 1, Ar1, Ar3 and Ar4 may each independently be a C6-C60 aryl group unsubstituted or substituted with at least one R10a, and is Ar2 may be selected from a C1-C60 heteroaryl group unsubstituted or substituted with at least one R10a and a C6-C60 aryl group unsubstituted or substituted with at least one R10a.
In one or more embodiments, in Formula 1, R1 to R3 may each independently be selected from hydrogen and deuterium. In one or more embodiments, in Formula 1, L1 may be a single bond. When L1 is a single bond, N is directly bonded to carbazole, positively affecting the hole transporting ability of the compound represented by Formula 1. In addition, this may have a positive effect on the stabilization of the interface between the first electrode and the layer including the compound represented by Formula 1 (for example, hole transport layer).
In one or more embodiments, Ar1 to Ar4 may each independently be one of
Formulae 2a to 2d:
wherein, in Formulae 2a to 2d, Z1 to Z6 may each independently be selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —C(Q1)(Q2)(Q3), —Si(Q1)(Q2)(Q3), —N(Q1)(Q2), —B(Q1)(Q2), —C(═O)(Q1), —S(═O)2(Q1), and —P(═O)(Q1)(Q2),
b1 may be an integer from 1 to 5,
b2 may be an integer from 1 to 7,
b3 and b5 may each independently be an integer from 1 to 3,
b4 and b6 may each independently be an integer from 1 to 4, and
Q1 to Q3 may each independently be: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C1-C60 alkyl group; a C2-C60 alkenyl group; a C2-C60 alkynyl group; a C1-C60 alkoxy group; a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C7-C60 aryl alkyl group or C2-C60 heteroaryl alkyl group, each unsubstituted or substituted with deuterium, —F, a cyano group, C1-C60 alkyl group, C1-C60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.
For example, Ar1, Ar3, and Ar4 may each independently be Formula 2a, and Ar2 may be one of Formulae 2a to 2d. In one or more embodiments, the compound represented by Formula 1 may be represented by Formula 2 below:
In Formula 2, Ar1 to Ar4, R1 to R3, L1, m, and a1 to a3 may be the same as defined in Formula 1, R4 may be defined the same as R1 of Formula 1, and a4 may be an integer from 1 to 6.
In one or more embodiments, Formula 2 may be represented by Formula 2-1:
In Formula 2-1, Ar1 to Ar4, R1 to R4, L1, m, and a1 to a4 may be the same as defined in Formula 2.
In one or more embodiments, Formula 1 may be represented by Formula 3.
In Formula 3, Ar1 to Ar4, R1 to R3, L1, m, and a1 to a3 may each be the same as defined in Formula 1, R4 may be the same as defined with respect to R1 of Formula 1, and a4 may be an integer from 1 to 6.
In one or more embodiments, Formula 3 may be represented by Formula 3-1:
In Formula 3-1, Ar1 to Ar4, R1 to R4, L1, m, and a1 to a4 may each be the same as defined in Formula 3.
In one or more embodiments, Formula 1 may be represented by Formula 4:
In Formula 4, Ar1 to Ar4, R1 to R3, L1, m, and a1 to a3 may each be the same as defined in Formula 1, R4 may be the same as defined with respect to R1 of Formula 1, and a4 may be an integer from 1 to 6.
In one or more embodiments, Formula 4 may be represented by Formula 4-1:
In Formula 4-1, Ar1 to Ar4, R1 to R4, L1, m, and a1 to a4 may each be the same as defined in Formula 4.
In one or more embodiments, the compound represented by Formula 1 may be one of the compounds below.
Another embodiment provides an electronic apparatus including the light-emitting device. In one or more embodiments, the electron apparatus may further include a thin-film transistor, the thin-film transistor includes a source electrode and a drain electrode, and the first electrode of the light-emitting device may be electrically connected to at least one of the source and drain electrodes of the thin-film transistor. In one or more embodiments, the electronic apparatus may further include a color filter, a color conversion layer, a touch screen layer, a polarizing layer, or any combination thereof.
Particularly,
In
The first electrode 110 may be formed by, for example, applying a material for forming the first electrode 110 onto the substrate by using a deposition or sputtering method. When the first electrode 110 is an anode, a metal oxide having a work function value of about −5.3 eV or less as described above may be used as the material for forming the first electrode. The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. The first electrode 110 may have a single-layered structure consisting of a single layer or a multi-layered structure including a plurality of layers.
The interlayer 130 may be located on the first electrode 110 The interlayer 130 is includes an emission layer. The interlayer 130 may further include a hole transport region placed between the first electrode 110 and the emission layer and an electron transport region placed between the emission layer and the second electrode 150. The interlayer 130 may further include, in addition to various organic materials, metal-containing compounds such as organometallic compounds, inorganic materials such as quantum dots, and the like.
In one or more embodiments, the interlayer 130 may include i) two or more emission layers sequentially stacked between the first electrode 110 and the second electrode 150 and ii) a charge generation layer located between the two or more emission layers. When the interlayer 130 includes the emission layer and the charge generation layer as described above, the light-emitting device 10 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 consisting of a plurality of different materials, or iii) a multi-layered structure including a plurality of layers including different materials. The hole transport region may include a hole transport layer. The hole transport region may further include an emission auxiliary layer, an electron blocking layer, or any combination thereof. The hole transport layer includes the compound represented by Formula 1, and the description of the compound represented by Formula 1 provided above may be referred to. For example, the hole transport region may have a multi-layered structure of hole transport layer/emission auxiliary layer, or hole transport layer/electron blocking layer, which are sequentially stacked in this stated order from the first electrode 110.
The hole transport region may include a compound represented by Formula 201, a is compound represented by Formula 202, or any combination thereof:
wherein, in Formulae 201 and 202,
L201 to L204 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a,
L205 may be *—O—*′, *—S—*′, *—N(Q201)-*′, a C1-C20 alkylene group unsubstituted or substituted with at least one R10a, a C2-C20 alkenylene group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a,
xa1 to xa4 may each independently be an integer from 0 to 5,
xa5 may be an integer from 1 to 10,
R201 to R204 and Q201 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a,
R201 and R202 may optionally be linked to each other, via a single bond, a C1-C5 alkylene group unsubstituted or substituted with at least one R10a, or a C2-C5 alkenylene group unsubstituted or substituted with at least one R10a, to form a C8-C60 polycyclic unsubstituted or substituted with at least one R10a (for example, a carbazole group),
R203 and R204 may optionally be linked to each other, via a single bond, a C1-C5 alkylene group unsubstituted or substituted with at least one R10a, or a C2-C5 alkenylene group unsubstituted or substituted with at least one R10a, to form a C8-C60 polycyclic group unsubstituted or substituted with at least one R10a, and
na1 may be an integer from 1 to 4.
In one or more embodiments, each of Formulae 201 and 202 may include at least one of groups represented by Formulae CY201 to CY217.
The variables R10b and R10c in Formulae CY201 to CY217 may each be the same as described with respect to 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. In one or more embodiments, ring CY201 to ring CY204 in Formulae CY201 to CY217 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.
In one or more embodiments, each of Formulae 201 and 202 may include at least one of groups represented by Formulae CY201 to CY203. In one or more embodiments, Formula 201 may include at least one of groups represented by Formulae CY201 to CY203 and at least one of groups represented by Formulae CY204 to CY217. In one or more embodiments, xa1 in Formula 201 may be 1, R201 may be a group represented by one of Formulae CY201 to CY203, xa2 may be 0, and R202 may be a group represented by one of Formulae CY204 to CY207.
In one or more embodiments, each of Formulae 201 and 202 may not include a group represented by one of Formulae CY201 to CY203. In one or more embodiments, each of Formulae 201 and 202 may not include a group represented by one of Formulae CY201 to CY203, and may include at least one of groups represented by Formulae CY204 to CY217. In one or more embodiments, each of Formulae 201 and 202 may not include a group represented by one of Formulae CY201 to CY217.
For example, the hole transport region may include 4′,4″-tris[phenyl(m-tolyl)amino]triphenylamine (m-MTDATA), 1-N,1-N-bis[4-(diphenylamino)phenyl]-4-N,4-N-diphenylbenzene-1,4-diamine (TDATA), 4,4′,4″-tris[2-naphthyl(phenyl)amino]triphenylamine (2-TNATA), bis(naphthalen-1-yl)-N,N′-bis(phenyl)benzidine (NPB or NPD), N4,N4′-di(naphthalen-2-yl)-N4,N4′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (β-NPB), N,N′-bis(3-methylphenyl) -N,N′-diphenylbenzidine (TPD), N,N′-bis(3-methylphenyl)-N,N′-diphenyl-9,9-spirobifluorene-2,7-diamine (Spiro-TPD), N2,N7-di-1-naphthalenyl-N2,N7-diphenyl-9,9′-spirobi[9H-fluorene]-2,7-diamine (Spiro-NPB), N,N′-di(1-naphthyl)-N,N′-diphenyl-2,2′-dimethyl-(1,1′-biphenyl)-4,4′-diamine (methylated-NPB), 4,4′-cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine] (TAPC), N,N,N′,N′-tetrakis(3-methylphenyl)-3,3′-dimethylbenzidine (HMTPD), 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA)), poly(3,4-ethylenedioxythiophene)/poly(4-styrenesulfonate)(PEDOT/PSS), polyaniline/camphor sulfonic acid (PANI/CSA), polyaniline/poly(4-styrenesulfonate) (PANI/PSS), or any combination thereof.
The thickness of the hole transport region may be in a range of about 50 Å to about 10,000 Å, for example, about 100 Å to about 4,000 Å. When the hole transport region includes a hole transport layer, an electron blocking layer or any combination thereof, the thickness of the hole transport layer may be 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 and the hole transport layer are within the ranges described above, satisfactory hole transportation 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 from the emission layer, and the electron-blocking layer may block the leakage of electrons from the emission layer to the hole transport region. Materials that may be included in the hole transport region may be included in the emission auxiliary layer and the electron blocking layer.
When the light-emitting device 10 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 sub-pixels. In one or more embodiments, the emission layer may have a stacked structure of two or more layers of the red emission layer, the green emission layer, and the blue emission layer, in which the two or more layers contact each other or are separated from each other. In one or more embodiments, the emission layer may have a structure in which two or more materials of a red light-emitting material, a green light-emitting material, and a blue light-emitting material are mixed with each other in a single layer, and thus emit white light.
The emission layer may include a host and a dopant. The dopant may include a phosphorescent dopant, a fluorescent dopant, or any combination thereof. The amount of the is dopant in the emission layer may be from about 0.01 to about 15 parts by weight with respect to 100 parts by weight of the host. In one or more embodiments, the emission layer may include a quantum dot.
In other embodiments, the emission layer may include a delayed fluorescence material. The delayed fluorescence material may act 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, for example, about 200 Å to about 600 Å. When the thickness of the emission layer is within the ranges described above, excellent light-emission characteristics may be obtained without a substantial increase in driving voltage.
In one or more embodiments, the host may include a compound represented by Formula 301 below:
[Ar301]xb11-[(L301)xb1-R301]xb21 Formula 301
wherein, in Formula 301,
Ar301 and L301 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a,
xb11 may be 1, 2, or 3,
xb1 may be an integer from 0 to 5,
R301 may be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkenyl group unsubstituted or substituted with at least one R10a, a C2-C60 alkynyl group unsubstituted or substituted with at least one R10a, a C1-C60 alkoxy group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, —Si(Q301)(Q302)(Q303), —N(Q301)(Q302), —B(Q301)(Q302), —C(═O)(Q301), —S(═O)2(Q301), or —P(═O)(Q301)(Q302),
xb21 may be an integer from 1 to 5, and
Q301 to Q303 are each the same as described with respect to Q1.
For example, when xb11 in Formula 301 is 2 or more, two or more of Ar301(s) may be linked to each other via a single bond.
In one or more embodiments, the host may include a compound represented by Formula 301-1, a compound represented by Formula 301-2, or any combination thereof:
In Formulae 301-1 and 301-2,
ring A301 to ring A304 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a,
X301 may be O, S, N-[(L304)xb4-R304], C(R304)(R305), or Si(R304)(R305),
xb22 and xb23 may each independently be 0, 1, or 2,
L301, xb1, and R301 are each the same as described,
L302 to L304 are each independently the same as described with respect to L301,
xb2 to xb4 may each independently be the same as described with respect to xb1, and
R302 to R305 and R311 to R314 are each the same as described with respect to R301.
In one or more embodiments, the host may include an alkali earth metal complex, a post-transition metal complex, or any combination thereof. In one or more embodiments, the host may include a Be complex (for example, Compound H55), an Mg complex, a Zn complex, or any combination thereof.
In other embodiments, the host may include one of Compounds H1 to H124, 9,10-di(2-naphthyl)anthracene (ADN), 2-methyl-9,10-bis(naphthalen-2-yl)anthracene (MADN), 9,10-di-(2-naphthyl)-2-t-butyl-anthracene (TBADN), 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP), 1,3-di(carbazol-9-yl)benzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), or any combination thereof:
The phosphorescent dopant may include at least one transition metal as a central 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. For example, the phosphorescent dopant may include an organometallic compound represented by Formula 401:
wherein, in Formulae 401 and 402,
M may be a transition metal (for example, iridium (Ir), platinum (Pt), palladium (Pd), osmium (Os), titanium (Ti), gold (Au), hafnium (Hf), europium (Eu), terbium (Tb), rhodium (Rh), rhenium (Re), or thulium (Tm)),
L401 may be a ligand represented by Formula 402, and xc1 may be 1, 2, or3, wherein when xc1 is 2 or more, two or more of L401(s) may be identical to or different from each other,
L402 may be an organic ligand, xc2 may be 0, 1, 2, 3, or 4, and when xc2 is 2 or more, two or more of L402(s) may be identical to or different from each other,
X401 and X402 may each independently be nitrogen or carbon,
ring A401 and ring A402 may each independently be a C3-C60 carbocyclic group or a C1-C60 heterocyclic group,
T401 may be a single bond, —O—,—S—, —C(═O)—, —N(Q411)—, —C(Q411)(Q412)—, —C(Q411)═C(Q412)—, —C(Q411)═, or ═C═,
X403 and X404 may each independently be a chemical bond (for example, a covalent bond or a coordination bond), O, S, N(Q413), B(Q413), P(Q413), C(Q413)(Q414), or Si(Q413)(Q414),
Q411 to Q414 are each the same as described with respect to Q1,
R401 and R402 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C20 alkyl group unsubstituted or substituted with at least one R10a, a C1-C20 alkoxy group unsubstituted or substituted with at least one R10a, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, —Si(Q401)(Q402)(Q403), —N(Q400(Q402), —B(Q401)(Q402), —C(═O)(Q401), —S(═O)2(Q401) or —P(═O)(Q401)(Q402),
Q401 to Q403 are each the same as described with respect to Q1,
xc11 and xc12 may each independently be an integer from 0 to 10, and
* and *′ in Formula 402 each indicate a binding site to M in Formula 401.
For example, in Formula 402, i) X401 may be nitrogen, and X402 may be carbon, or ii) each of X401 and X402 may be nitrogen.
In one or more embodiments, when xc1 in Formula 402 is 2 or more, two ring A401(s) in two or more of L401(s) may be optionally linked to each other via T402, which is a linking group, and two ring A402(s) may be optionally linked to each other via T403, which is a linking group (see Compounds PD1 to PD4 and PD7). The variables T402 and T403 are each the same as described with respect to T401.
L402 in Formula 401 may be an organic ligand. For example, L402 may include a halogen group, a diketone group (for example, an acetylacetonate group), a carboxylic acid group (for example, a picolinate group), a group —C(═O), an isonitrile group, a —CN group, a phosphorus group (for example, a phosphine group, a phosphite group, etc.), or any combination thereof.
The phosphorescent dopant may include, for example, one of compounds PD1 to PD39, or any combination thereof:
The fluorescent dopant may include an amine group-containing compound, a styryl group-containing compound, or any combination thereof.
In one or more embodiments, the fluorescent dopant may include a compound represented by Formula 501:
wherein, in Formula 501,
Ar501, L501 to L503, R501, and R502 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a,
xd1 to xd3 may each independently be 0, 1, 2, or 3, and
xd4 may be 1, 2, 3, 4, 5, or 6.
In one or more embodiments, Ar501 in Formula 501 may be a condensed cyclic group (for example, an anthracene group, a chrysene group, or a pyrene group) in which three or more monocyclic groups are condensed together. In one or more embodiments, xd4 in Formula 501 may be 2.
In one or more embodiments, the fluorescent dopant may include: one of Compounds FD1 to FD36; DPVBi; DPAVBi; or any combination thereof:
The emission layer may include a delayed fluorescence material. The delayed fluorescence material may be selected from compounds capable of emitting delayed fluorescent light based on a delayed fluorescence emission mechanism. The delayed fluorescence material included in the emission layer may act as a host or a dopant depending on the type of other materials included in the emission layer.
In one or more embodiments, the difference between the triplet energy level in electron volt (eV) of the delayed fluorescence material and the singlet energy level (eV) of the delayed fluorescence material may be greater than or equal to about 0 eV and less than or equal to about 0.5 eV. When the difference between the triplet energy level (eV) of the delayed fluorescence material and the singlet energy level (eV) of the delayed fluorescence material satisfies the above-described range, up-conversion from the triplet state to the singlet state of the delayed fluorescence materials may effectively occur, and thus, the emission efficiency of the light-emitting device 10 may be improved.
In one or more embodiments, the delayed fluorescence material may include i) a material including at least one electron donor (for example, a π electron-rich C3-C60 cyclic group, such as a carbazole group) and at least one electron acceptor (for example, a sulfoxide group, a cyano group, or a π electron-deficient nitrogen-containing C1-C60 cyclic group), and ii) a material including a C8-C60 polycyclic group in which two or more cyclic groups are condensed while sharing boron (B).
In one or more embodiments, the delayed fluorescence material may include at is least one of Compounds DF1 to DF9:
The emission layer may include a quantum dot. The diameter of the quantum dot may be, for example, in a range of about 1 nm to about 10 nm. The quantum dot may be synthesized by a wet chemical process, a metal organic chemical vapor deposition process, a molecular beam epitaxy process, or any process similar thereto.
The wet chemical process is a method including mixing a precursor material with an organic solvent and then growing a quantum dot particle crystal. When the crystal grows, the organic solvent naturally acts as a dispersant coordinated on the surface of the quantum dot crystal and controls the growth of the crystal so that the growth of quantum dot particles can be controlled through a process which costs lower, and is easier than vapor deposition methods, such as metal organic chemical vapor deposition (MOCVD) or molecular beam epitaxy (MBE),
The quantum dot may include semiconductor compounds of Groups II-VI, semiconductor compounds of Groups III-V, semiconductor compounds of Groups semiconductor compounds of Groups I, III, and VI, semiconductor compounds of Groups IV-VI, an element or a compound of Group IV, or any combination thereof.
Examples of the semiconductor compound of Groups II-VI may include binary compounds, such as CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, or MgS; ternary compounds, such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, or MgZnS; quaternary compounds, such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, or HgZnSTe; or any combination thereof.
Examples of the semiconductor compound of Groups III-V may include: binary is compounds, such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, or InSb; ternary compounds, such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, or InPSb; quaternary compounds, such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, or InAlPSb; or any combination thereof. The semiconductor compound of Groups III-V may further include Group II elements. Examples of the semiconductor compound of Groups III-V further including the Group II element may include InZnP, InGaZnP, InAlZnP, and the like.
Examples of the semiconductor compound of Groups III-VI may include binary compounds, such as GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2Se3, or InTe; ternary compounds, such as InGaS3 or InGaSe3; or any combination thereof. Examples of the semiconductor compound of Groups I, III, and VI may include ternary compounds, such as AgInS, AgInS2, CuInS, CuInS2, CuGaO2, AgGaO2, or AgAlO2; or any combination thereof.
Examples of the semiconductor compound of Groups IV-VI may include: binary compounds, such as SnS, SnSe, SnTe, PbS, PbSe, or PbTe; ternary compounds, such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, or SnPbTe; quaternary compounds, such as SnPbSSe, SnPbSeTe, or SnPbSTe; or any combination thereof. The element or compound of Group IV may include: a single element compound, such as Si or Ge; a binary compound, such as SiC or SiGe; or any combination thereof.
Each element included in multi-element compounds such as the binary compound, the ternary compound, and the quaternary compound, may exist at a uniform concentration or non-uniform concentration in a particle. The quantum dot may have a single structure in which the concentration of each element in the quantum dot is uniform, or a core-shell dual structure. For example, the material included in the core and the material included in the shell may be different from each other.
The shell of the quantum dot may act as a protective layer that prevents chemical degeneration of the core to maintain semiconductor characteristics, and/or as a charging layer that imparts electrophoretic characteristics to the quantum dot. The shell may be a single layer or a multi-layer. The interface between the core and the shell may have a concentration gradient in which the concentration of an element existing in the shell decreases toward the center of the core.
Examples of the shell of the quantum dot may be include oxides of a metal, a metalloid, or a non-metal, a semiconductor compound, and any combination thereof. Examples of the oxides of the metal, metalloid, or non-metal 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, as described herein, a semiconductor compound of Groups II-VI; a semiconductor compound of Groups III-V; a semiconductor compound of Groups III-VI; a semiconductor compound of Groups I, III, and VI; a semiconductor compound of Group IV-VI; and any combination thereof. In addition, the semiconductor compound may include 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 full width at half maximum (FWHM) of the emission wavelength spectrum of the quantum dot may be about 45 nm or less, for example, about 40 nm or less, for example, about 30 nm or less, and within these ranges, color purity or color reproducibility may be is increased. In addition, since the light through the quantum dot is emitted in all directions, the wide viewing angle may be improved. In addition, the quantum dot may be a generally spherical particle, a generally pyramidal particle, a generally multi-armed particle, a generally cubic nanoparticle, a generally nanotube-shaped particle, a generally nanowire-shaped particle, a generally nanofiber-shaped particle, or a generally nanoplate-shaped particle.
Because the energy band gap may be adjusted by controlling the size of the quantum dot, light having various wavelength bands may be obtained from the quantum dot emission layer. Accordingly, by using quantum dots of different sizes, a light-emitting device that emits light of various wavelengths may be implemented. In one or more embodiments, the size of the quantum dot may be selected to emit red, green and/or blue light. In addition, the size of the quantum dot may be configured to emit white light by combination of light of various colors.
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 consisting of a plurality of different materials, or iii) a multi-layered structure including a plurality of layers including different materials. The electron transport region may include a hole-blocking layer, an electron transport layer, an electron injection layer, or any combination thereof. For example, 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, or the like, the constituting layers of each structure being sequentially stacked from the emission layer.
In one or more embodiments, the electron transport region (for example, the hole-blocking layer, or the 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. For example, the electron transport region may include a compound represented by Formula 601 below:
[Ar601]xe11-[(L601)xe1-R601]xe21 Formula 601
wherein, in Formula 601,
Ar601 and L601 may each independently be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a,
xe11 may be 1, 2, or 3,
xe1 may be 0, 1, 2, 3, 4, or 5,
R601 may be a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a, —Si(Q601)(Q602)(Q603), —C(═O)(Q601), —S(═O)2(Q601), or —P(═O)(Q601)(Q602),
Q601 to Q603 are each the same as described with respect to Q1,
xe21 may be 1, 2, 3, 4, or 5, and
at least one of Ar601, L601, and R601 may each independently be a π electron-deficient nitrogen-containing C1-C60 cyclic group unsubstituted or substituted with at least one R10a.
For example, when xe11 in Formula 601 is 2 or more, two or more of Ar601(s) may be linked to each other via a single bond. In other embodiments, Ar601 in Formula 601 may be a substituted or unsubstituted anthracene group.
In other embodiments, the electron transport region may include a compound represented by Formula 601-1:
wherein, in Formula 601-1,
X614 may be N or C(R614), X615 may be N or C(R615), X616 may be N or C(R616), and at least one of X614 to X616 may be N,
L611 to L613 are each the same as described with respect to L601,
xe611 to xe613 are each the same as described with respect to xe1,
R611 to R613 are each the same as described with respect to R601, and
R614 to R616 may each independently be hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C20 alkyl group, a C1-C20 alkoxy group, a C3-C60 carbocyclic group unsubstituted or substituted with at least one R10a, or a C1-C60 heterocyclic group unsubstituted or substituted with at least one R10a.
For example, xe1 and xe611 to xe613 in Formulae 601 and 601-1 may each independently be 0, 1, or 2.
The electron transport region may include one of Compounds ET1 to ET45, 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), 4,7-diphenyl-1,10-phenanthroline (Bphen), tris-(8-hydroxyquinoline)aluminum (Alq3), bis(2-methyl-8-quinolinolato-N1,O8)-(1,1′-biphenyl-4-olato)aluminum (BAlq), 3-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-4-phenyl-4H-1,2,4-triazole (TAZ), 4-(naphthalen-1-yl)-3,5-diphenyl-4H-1,2,4-triazole (NTAZ), or any combination thereof:
The thickness of the electron transport region may be from about 100 Å to about 5,000 Å, for example, about 160 Å to about 4,000 Å. When the electron transport region includes the hole blocking layer, the electron transport layer, or any combination thereof, the thickness of s the hole blocking layer or electron transport layer may each independently be from 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 from about 100 Å to about 1,000 Å, for example, about 150 Å to about 500 Å. When the thicknesses of the hole blocking layer and/or the electron transport layer are within these ranges, satisfactory electron transporting 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. The metal ion of an alkali metal complex may is be a Li ion, a Na ion, a K ion, a Rb ion, or a Cs ion, and the metal ion of an alkaline earth metal complex may be a Be ion, a Mg ion, a Ca ion, a Sr ion, or a Ba ion. A ligand coordinated with the metal ion of the alkali metal complex or the alkaline earth-metal complex may include a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenylbenzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.
For example, the metal-containing material may include a Li complex. The Li complex may include, for example, Compound ET-D1 (lithium quinolate, LiQ) or ET-D2:
The electron transport region may include an electron injection layer that facilitates the injection of electrons from the second electrode 150. The electron injection layer may directly contact the second electrode 150. 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 consisting of a plurality of different materials, or iii) a multi-layered structure including a plurality of layers including 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 include Li, Na, K, Rb, Cs, or any combination thereof. The alkaline earth metal may include Mg, Ca, Sr, Ba, or any combination thereof. The rare earth metal may include 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 (for example, fluorides, chlorides, bromides, or iodides), or tellurides of the alkali metal, the alkaline earth metal, and the rare earth metal, or any combination thereof.
The alkali metal-containing compound may include alkali metal oxides such as Li2O, Cs2O, or K2O, and alkali metal halides such as LiF, NaF, CsF, KF, LiI, NaI, CsI, KI, or any combination thereof. The alkaline earth metal-containing compound may include an alkaline earth metal compound, such as BaO, SrO, CaO, BaxSr1-xO (wherein x is a real number satisfying the condition of 0<x<1), BaxCa1-xO (wherein x is a real number satisfying the condition of 0<x<1), and the like. The rare earth metal-containing compound may include YbF3, ScF3, Sc2O3, Y2O3, Ce2O3, GdF3, TbF3, YbI3, ScI3, TbI3, or any combination thereof. In one or more embodiments, the rare earth metal-containing compound may include a lanthanide metal telluride. Examples of the lanthanide metal telluride may be 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, and Lu2Te3.
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, the alkaline earth metal, and the is rare earth metal and ii), as a ligand bonded to the metal ion, for example, a hydroxyquinoline, a hydroxyisoquinoline, a hydroxybenzoquinoline, a hydroxyacridine, a hydroxyphenanthridine, a hydroxyphenyloxazole, a hydroxyphenylthiazole, a hydroxyphenyloxadiazole, a hydroxyphenylthiadiazole, a hydroxyphenylpyridine, a hydroxyphenylbenzimidazole, a hydroxyphenylbenzothiazole, a bipyridine, a phenanthroline, a cyclopentadiene, or any combination thereof.
The electron injection layer may consist exclusively 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 one or more embodiments, the electron injection layer may further include an organic material (for example, a compound represented by Formula 601).
In one or more embodiments, the electron injection layer may consist of i) an alkali metal-containing compound (for example, an alkali metal halide), ii) a) an alkali metal-containing compound (for example, an alkali metal halide); and b) an alkali metal, an alkaline earth metal, a rare earth metal, or any combination thereof. For example, the electron injection layer may be a KI:Yb co-deposited layer, an RbI:Yb co-deposited layer, or the like.
When the electron injection layer further includes an organic material, 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 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, for example, about 3 Å to about 90 Å. When the thickness of the electron injection layer is within the ranges described above, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.
The second electrode 150 may be placed on the interlayer 130 having a structure as described above. The second electrode 150 may be a cathode, which is an electron injection electrode, and as the material for the second electrode 150, a metal, an alloy, an electrically conductive compound, or any combination thereof, each having a low-work function, may be used.
In one or more embodiments, the second electrode 150 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), an ITO, an indium zinc oxide (IZO), or any combination thereof. The second electrode 150 may be a transmissive electrode, a semi-transmissive electrode, or a reflective electrode. The second electrode 150 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 110, and/or a second capping layer may be located outside the second electrode 150. In particular, the light-emitting device 10 may have a structure in which the first capping layer, the first electrode 110, the interlayer 130, and the second electrode 150 are sequentially stacked in the stated order, a structure in which the first electrode 110, the interlayer 130, the second electrode 150 and the is second capping layer are sequentially stacked in the stated order, or a structure in which the first capping layer, the first electrode 110, the interlayer 130, the second electrode 150 and the second capping layer are sequentially stacked in the stated order.
Light generated in an emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the first electrode 110 which is a semi-transmissive electrode or a transmissive electrode, and the first capping layer. Light generated in an emission layer of the interlayer 130 of the light-emitting device 10 may be extracted toward the outside through the second electrode 150 which is a semi-transmissive electrode or a transmissive electrode, and the second capping layer.
Although not wanting to be bound by theory, the first capping layer and the second capping layer may increase external emission efficiency according to the principle of constructive interference. Accordingly, the light extraction efficiency of the light-emitting device 10 is increased, so that the luminescence efficiency of the light-emitting device 10 may be improved. Each of the first capping layer and second capping layer may include a material having a refractive index of about 1.6 or more (at 589 nm).
The first capping layer and the second capping layer may each independently be an organic capping layer including an organic material, an inorganic capping layer including an inorganic material, or an organic-inorganic 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, porphyrin derivatives, phthalocyanine derivatives, naphthalocyanine derivatives, alkali metal complexes, alkaline earth metal complexes, or any combination thereof. The is carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may be optionally substituted with a substituent including O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof. In one or more embodiments, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound. In one or more embodiments, at least one of the first capping layer and the second capping layer may each independently include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof.
In one or more embodiments, at least one of the first capping layer and the second capping layer may each independently include one of Compounds HT28 to HT33, one of Compounds CP1 to CP6, N4,N4′-di(naphthalen-2-yl)-N4,N4′-diphenyl-[1,1′-biphenyl]-4,4′-diamine (β-NPB), or any combination thereof:
The light-emitting device 10 may be included in various electronic apparatuses. In one or more embodiments, the electronic apparatus including the light-emitting device 10 may be a light-emitting apparatus, an authentication apparatus, and the like. The electronic apparatus (for example, light-emitting apparatus) may further include, in addition to the light-emitting device 10, i) a color filter, ii) a color conversion layer, or iii) a color filter and a color conversion layer. The color filter and/or the color conversion layer may be located in at least one path of light emitted from the light-emitting device 10. For example, the light emitted from the light-emitting device 10 may be blue light. Details on the light-emitting device 10 can be described above. In one or more embodiments, the color conversion layer may include quantum dots. The quantum dot may be, for example, a quantum dot as described herein.
The electronic apparatus may include a first substrate. The first substrate may include a plurality of subpixel areas, the color filter may include a plurality of color filter areas respectively overlapping the subpixel areas, and the color conversion layer may include a plurality of color conversion areas respectively overlapping the subpixel areas. A pixel-defining film may be located in the subpixel areas to define each of the subpixel areas.
The color filter may further include a plurality of color filter areas and light-shielding patterns located among the color filter areas, and the color conversion layer may include a plurality of color conversion areas and light-shielding patterns located among the color conversion areas.
The color filter areas (or the color conversion areas) may include a first area emitting first color light, a second area emitting second color light, and/or a third area emitting is third color light, and the first color light, the second color light, and/or the third color light may have different maximum emission wavelengths from one another. For example, the first color light may be red light, the second color light may be green light, and the third color light may be blue light. For example, the color filter areas (or the color conversion areas) may include quantum dots. In detail, the first area may include a red quantum dot, the second area may include a green quantum dot, and the third area may not include a quantum dot. Details on the quantum dot can be as described above. The first area, the second area, and/or the third area may each include a scatterer.
In one or more embodiments, the light-emitting device 10 may emit first light, the first area may absorb the first light to emit first first-color light, the second area may absorb the first light to emit second first-color light, and the third area may absorb the first light to emit third first-color light. In this regard, the first first-color light, the second first-color light, and the third first-color light may have different maximum emission wavelengths. In detail, the first light may be blue light, the first first-color light may be red light, the second first-color light may be green light, and the third first-color light may be blue light.
The electronic apparatus may further include a thin-film transistor in addition to the light-emitting device 10 as described above. The thin-film transistor may include a source electrode, a drain electrode, and an activation layer, wherein any one of the source electrode and the drain electrode may be electrically connected to any one of the first electrode and the second electrode of the light-emitting device 10. The thin-film transistor may further include a gate electrode, a gate insulating film, and the like. The activation layer may include a crystalline silicon, an amorphous silicon, an organic semiconductor, an oxide semiconductor, and the like.
The electronic apparatus may further include a sealing portion for sealing the is light-emitting device 10. The sealing portion and/or the color conversion layer may be placed between the color filter and the light-emitting device 10. The sealing portion allows light from the light-emitting device 10 to be extracted to the outside, while simultaneously preventing ambient air and moisture from penetrating into the light-emitting device 10. The sealing portion may be a sealing substrate including a transparent glass substrate or a plastic substrate. The sealing portion may be a thin-film encapsulation layer including at least one layer of an organic layer and/or an inorganic layer. When the sealing portion is a thin film encapsulation layer, the electronic apparatus may be flexible.
Various functional layers may be additionally located on the sealing portion, in addition to the color filter and/or the color conversion layer, according to the use of the electronic apparatus. The functional layers may include a touch screen layer, a polarizing layer, and the like. The touch screen layer may be a pressure-sensitive touch screen layer, a capacitive touch screen layer, or an infrared touch screen layer. The authentication apparatus may be, for example, a biometric authentication apparatus that authenticates an individual by using biometric information of a living body (for example, fingertips, pupils, or the like). The authentication apparatus may further include, in addition to the light-emitting device 10, a biometric information collector.
The electronic apparatus may take the form of or be applied to various displays, light sources, lighting, personal computers (for example, a mobile personal computer), mobile phones, digital cameras, electronic organizers, electronic dictionaries, electronic game machines, medical instruments (for example, electronic thermometers, sphygmomanometers, blood glucose meters, pulse measurement devices, pulse wave measurement devices, electrocardiogram displays, ultrasonic diagnostic devices, or endoscope displays), fish finders, various measuring is instruments, meters (for example, meters for a vehicle, an aircraft, and a vessel), projectors, and the like.
The electronic apparatus 180 of
The TFT 200 may be located on the buffer layer 210. The TFT 200 may include an activation layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.
The activation layer 220 may include an inorganic semiconductor such as a silicon or a polysilicon, an organic semiconductor, or an oxide semiconductor, and may include a source region, a drain region and a channel region. A gate insulating film 230 for insulating the activation layer 220 from the gate electrode 240 may be located on the activation layer 220, and the gate electrode 240 may be located on the gate insulating film 230.
An interlayer insulating film 250 may be located on the gate electrode 240. The interlayer insulating film 250 may be located between the gate electrode 240 and the source electrode 260 and between the gate electrode 240 and the drain electrode 270 to provide insulation therebetween. The source electrode 260 and the drain electrode 270 may be located on is the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may be formed to expose the source region and the drain region of the activation layer 220, and the source electrode 260 and the drain electrode 270 may be located in contact with the exposed portions of the source region and the drain region of the activation layer 220.
The TFT 200 is electrically connected to a light-emitting device 10 to drive the light-emitting device 10, and is covered by a passivation layer 280. The passivation layer 280 may include an inorganic insulating film, an organic insulating film, or any combination thereof. The light-emitting device 10 is provided on the passivation layer 280. The light-emitting device 10 may include a first electrode 110, an interlayer 130, and a second electrode 150.
The first electrode 110 may be located on the passivation layer 280. The passivation layer 280 may be located to expose a portion of the drain electrode 270, not fully covering the drain electrode 270, and the first electrode 110 may be located to be connected to the exposed portion of the drain electrode 270.
A pixel defining layer 290 including an insulating material may be located on the first electrode 110. The pixel defining layer 290 may expose a region of the first electrode 110, and the interlayer 130 may be formed in the exposed region of the first electrode 110. The pixel defining layer 290 may be a polyimide or polyacrylic organic film. At least some layers of the interlayer 130 may extend beyond the upper portion of the pixel defining layer 290 to be located in the form of a common layer. The second electrode 150 may be located on the interlayer 130, and a capping layer 170 may be additionally formed on the second electrode 150. The capping layer 170 may be formed to cover the second electrode 150.
The encapsulation portion 300 may be located on the capping layer 170. The encapsulation portion 300 may be located on a light-emitting device to protect the light-emitting is device from moisture or oxygen. The encapsulation portion 300 may include: an inorganic film including a silicon nitride (SiNx), a silicon oxide (SiOx), an indium tin oxide, an indium zinc oxide, or any combination thereof; an organic film including a polyethylene terephthalate, a polyethylene naphthalate, a polycarbonate, a polyimide, a polyethylene sulfonate, a polyoxymethylene, a polyarylate, a hexamethyldisiloxane, an acrylic resin (for example, a polymethyl methacrylate, a polyacrylic acid, or the like), an epoxy-based resin (for example, an aliphatic glycidyl ether (AGE), or the like), or any combination thereof; or any combination of the inorganic film and the organic film.
The electronic apparatus 190 of
Respective layers included in the hole transport region, the emission layer, and respective layers included in the electron transport region may be formed in a certain region by using one or more suitable methods selected from 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 formed by vacuum deposition, the deposition may be performed at a deposition temperature of about 100° C. to about 500° C., a vacuum degree of about 10−8 torr to about 10−3 torr, and a deposition rate of about 0.01 Å/sec to about 100 Å/sec, in consideration of a material to be included in a layer to be formed and the structure of a layer to be formed.
When layers constituting the hole transport region, an emission layer, and layers constituting the electron transport region are formed by spin coating, the spin coating may be performed at a coating speed of about 2,000 rpm to about 5,000 rpm and at a heat treatment temperature of about 80° C. to about 200° C., in consideration of account a material to be included in a layer to be formed and the structure of a layer to be formed.
As used herein, the term “interlayer” as used herein refers to a single layer and/or all of a plurality of layers located between a first electrode and a second electrode of a light-emitting device.
As used herein, the term “quantum dot” refers to a crystal of a semiconductor compound, and may include any material capable of emitting light of various emission wavelengths according to the size of the crystal.
As used herein, the term “energy level” may be expressed in “electron volts” and “energy level” and “electron volt” may be abbreviated, independently, as “eV”.
As used herein, the term “fused” may refer to a ring having one or more sides in common with another ring, and includes a condensed ring.
As used herein, the term “atom” may mean an element or its corresponding is radical bonded to one or more other atoms.
The terms “hydrogen” and “deuterium” refer to their respective atoms and corresponding radicals with the deuterium radical abbreviated “—D”, and the terms “—F, —Cl, —Br, and —I” are radicals of, respectively, fluorine, chlorine, bromine, and iodine.
As used herein, a substituent for a monovalent group, e.g., alkyl, may also be, independently, a substituent for a corresponding divalent group, e.g., alkylene.
The term “C3-C60 carbocyclic group” as used herein refers to a cyclic group of 3-60 carbon atoms, consisting of carbons only as ring-forming atoms, and the term “C1-C60heterocyclic group” as used herein refers to a cyclic group of 1-60 carbon atoms, further having, in addition to carbon, a heteroatom, as ring-forming 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 two or more rings are fused with each other. For example, the C1-C60 heterocyclic group has 3 to 61 ring-forming atoms.
The “cyclic group” as used herein may include the C3-C60 carbocyclic group and the C1-C60 heterocyclic group.
The term “π electron-rich C3-C60 cyclic group” as used herein refers to a cyclic group that has three to sixty carbon atoms and does not include *—N═*′ as a ring-forming moiety, and the term “π electron-deficient nitrogen-containing C1-Cal cyclic group” as used herein refers to a heterocyclic group that has one to sixty carbon atoms and includes *—N═*′ as a ring-forming moiety.
For example, the C3-C60 carbocyclic group may be i) a T1 group or ii) a fused cyclic group in which at least two T1 groups are fused with each other, for example, a cyclopentadiene group, an adamantane group, a norbornane group, a benzene group, a pentalene is group, a naphthalene group, an azulene group, an indacene group, an acenaphthylene group, a phenalene group, a phenanthrene group, an anthracene group, a fluoranthene group, a triphenylene group, a pyrene group, a chrysene group, a perylene group, a pentaphene group, a heptalene group, a naphthacene group, a picene group, a hexacene group, a pentacene group, a rubicene group, a coronene group, an ovalene group, an indene group, a fluorene group, a spiro-bifluorene group, a benzofluorene group, an indenophenanthrene group, or an indenoanthracene group.
The C1-C60 heterocyclic group may be i) a T2 group, ii) a fused cyclic group in which at least two T2 groups are fused with each other, or iii) a fused cyclic group in which at least one T2 group and at least one T1 group are fused with each other, for example, a pyrrole group, a thiophene group, a furan group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a benzoindolocarbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonaphthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, a benzothienodibenzothiophene group, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzoisoxazole group, a benzothiazole group, a benzoisothiazole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a is benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a phenanthroline group, a cinnoline group, a phthalazine group, a naphthyridine group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, an imidazopyridazine group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, or the like.
The π electron-rich C3-C60 cyclic group may be i) a T1 group, ii) a fused cyclic group in which at least two T1 groups are fused with each other, iii) a T3 group, iv) a fused cyclic group in which at least two T3 groups are fused with each other, or v) a fused cyclic group in which at least one T3 group and at least one T1 group are fused with each other, for example, the C3-C60 carbocyclic group, a 1H-pyrrole group, a silole group, a borole group, a 2H-pyrrole group, a 3H-pyrrole group, a thiophene group, a furan group, an indole group, a benzoindole group, a naphthoindole group, an isoindole group, a benzoisoindole group, a naphthoisoindole group, a benzosilole group, a benzothiophene group, a benzofuran group, a carbazole group, a dibenzosilole group, a dibenzothiophene group, a dibenzofuran group, an indenocarbazole group, an indolocarbazole group, a benzofurocarbazole group, a benzothienocarbazole group, a benzosilolocarbazole group, a benzoindolocarbazole group, a benzocarbazole group, a benzonaphthofuran group, a benzonaphthothiophene group, a benzonaphthosilole group, a benzofurodibenzofuran group, a benzofurodibenzothiophene group, a benzothienodibenzothiophene group, or the like.
The π electron-deficient nitrogen-containing C1-C60 cyclic group may be i) a T4 group, ii) a fused cyclic group in which at least two T4 groups are fused with each other, iii) a fused cyclic group in which at least one T4 group and at least one T1 group are fused with each is other, iv) a fused cyclic group in which at least one T4 group and at least one T3 group are fused with each other, or v) a fused cyclic group in which at least one T4 group, at least one T1 group, and at least one T3 group are fused with one another, for example, a pyrazole group, an imidazole group, a triazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, a benzopyrazole group, a benzimidazole group, a benzoxazole group, a benzoisoxazole group, a benzothiazole group, a benzoisothiazole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a quinoline group, an isoquinoline group, a benzoquinoline group, a benzoisoquinoline group, a quinoxaline group, a benzoquinoxaline group, a quinazoline group, a benzoquinazoline group, a phenanthroline group, a cinnoline group, a phthalazine group, a naphthyridine group, an imidazopyridine group, an imidazopyrimidine group, an imidazotriazine group, an imidazopyrazine group, an imidazopyridazine group, an azacarbazole group, an azafluorene group, an azadibenzosilole group, an azadibenzothiophene group, an azadibenzofuran group, or the like.
The T1 group may be a cyclopropane group, a cyclobutane group, a cyclopentane group, a cyclohexane group, a cycloheptane group, a cyclooctane group, a cyclobutene group, a cyclopentene group, a cyclopentadiene group, a cyclohexene group, a cyclohexadiene group, a cycloheptene group, an adamantane group, a norbornane (or a bicyclo[2.2.1]heptane) group, a norbornene group, a bicyclo[1.1.1]pentane group, a bicyclo[2.1.1]hexane group, a bicyclo[2.2.2]octane group, or a benzene group.
The T2 group may be a furan group, a thiophene group, a 1H-pyrrole group, a silole group, a borole group, a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazole group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an is oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, an azasilole group, an azaborole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, a tetrazine group, a pyrrolidine group, an imidazolidine group, a dihydropyrrole group, a piperidine group, a tetrahydropyridine group, a dihydropyridine group, a hexahydropyrimidine group, a tetrahydropyrimidine group, a dihydropyrimidine group, a piperazine group, a tetrahydropyrazine group, a dihydropyrazine group, a tetrahydropyridazine group, or a dihydropyridazine group.
The T3 group may be a furan group, a thiophene group, a 1H-pyrrole group, a silole group, or a borole group.
The T4 group may be a 2H-pyrrole group, a 3H-pyrrole group, an imidazole group, a pyrazole group, a triazole group, a tetrazole group, an oxazole group, an isoxazole group, an oxadiazole group, a thiazole group, an isothiazole group, a thiadiazole group, an azasilole group, an azaborole group, a pyridine group, a pyrimidine group, a pyrazine group, a pyridazine group, a triazine group, or a tetrazine group.
The terms “the cyclic group, the C3-C60 carbocyclic group, the C1-C60 heterocyclic group, the π electron-rich C3-C60 cyclic group, or the π electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein refer to a group fused with any cyclic group, a monovalent group, or a polyvalent group (for example, a divalent group, a trivalent group, a tetravalent group, or the like), depending on the structure of a formula in connection with which the terms are used. In one or more embodiments, “a benzene group” may be a bengroup, a phenyl group, a phenylene group, or the like, which may be easily understood by one of ordinary skill in the art according to the structure of a formula including the “benzene group.”
Examples of the monovalent C3-C60 carbocyclic group and the monovalent C1-C60 is heterocyclic group are 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 C1-C60 heteroaryl group, a monovalent non-aromatic fused polycyclic group, and a monovalent non-aromatic fused heteropolycyclic group. Examples of the divalent C3-C60 carbocyclic group and the divalent C1-C60 heterocyclic group are 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 fused polycyclic group, and a substituted or unsubstituted divalent non-aromatic fused heteropolycyclic group.
The term “C1-C60 alkyl group” as used herein refers to a linear or branched aliphatic hydrocarbon monovalent group that has one to sixty carbon atoms, and examples thereof are 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 a structure corresponding to the C1-C60 alkyl group.
The term “C2-C60 alkenyl group” as used herein refers to a monovalent hydrocarbon group having at least one carbon-carbon double bond in the middle or at the terminus of the C2-C60 alkyl group, and examples thereof are an ethenyl group, a propenyl group, and a butenyl group. The term “C2-C60 alkenylene group” as used herein refers to a divalent is group having a structure corresponding to 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, and 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 a structure corresponding to 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 the C1-C60 alkyl group), and 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 cyclic group having three to ten carbon atoms, and examples thereof are a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantanyl group, a norbornanyl group (or bicyclo[2.2.1]heptyl group), a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, and a bicyclo[2.2.2]octyl group. The term “C3-C10 cycloalkylene group” as used herein refers to a divalent group having a structure corresponding to the C3-C10 cycloalkyl group.
The term “C1-C10 heterocycloalkyl group” as used herein refers to a monovalent cyclic group of 1-10 ten carbon atoms, further having, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms, and examples thereof are 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 a structure corresponding to the C1-C10 heterocycloalkyl group.
The term C3-C10 cycloalkenyl group used herein refers to a monovalent cyclic is group that has three to ten carbon atoms and at least one carbon-carbon double bond in the ring thereof and no aromaticity, and examples thereof are 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 a structure corresponding to the C3-C10 cycloalkenyl group.
The term “C1-C10 heterocycloalkenyl group” as used herein refers to a monovalent cyclic group of 1-10 carbon atoms, having, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms, and at least one carbon-carbon double bond in the cyclic structure thereof. Examples of the C1-C10 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 heterocycloalkenylene group” as used herein refers to a divalent group having a structure corresponding to the C1-C10 heterocycloalkenyl group.
The term “C6-C60 aryl group” as used herein refers to a monovalent group having a carbocyclic aromatic system having six to sixty carbon atoms, and the term “C6-C60 arylene group” as used herein refers to a divalent group having a carbocyclic aromatic system having six to sixty carbon atoms. Examples of the C6-C60 aryl group are 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 include two or more rings, the rings may be fused with each other.
The term “C1-C60 heteroaryl group” as used herein refers to a monovalent group having a heterocyclic aromatic system of 1-60 carbon atoms, having, in addition to a carbon is atom, at least one heteroatom, as ring-forming atoms. The term “C1-C60 heteroarylene group” as used herein refers to a divalent group having a heterocyclic aromatic system of 1-60 carbon atoms, having, in addition to carbon atoms, at least one heteroatom, as ring-forming atoms. Examples of the C1-C60 heteroaryl group are 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 include two or more rings, the rings may be fused with each other.
The term “monovalent non-aromatic fused polycyclic group” as used herein refers to a monovalent group (for example, having 8-60 carbon atoms) having two or more rings fused with each other, only carbon atoms as ring-forming atoms, and no aromaticity in its entire molecular structure. Examples of the monovalent non-aromatic fused polycyclic group are 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 fused polycyclic group” as used herein refers to a divalent group having a structure corresponding to a monovalent non-aromatic fused polycyclic group.
The term “monovalent non-aromatic fused heteropolycyclic group” as used herein refers to a monovalent group (for example, having one to sixty carbon atoms) having two or more rings fused with each other, and at least one heteroatom, in addition to carbon atoms, as ring-forming atoms, and no aromaticity in its entire molecular structure. Examples of the monovalent non-aromatic fused heteropolycyclic group are a pyrrolyl group, a thiophenyl group, is 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 benzoxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indeno carbazolyl 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 benzonaphtho silolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term “divalent non-aromatic fused heteropolycyclic group” as used herein refers to a divalent group having a structure corresponding to a monovalent non-aromatic fused heteropolycyclic group.
The term “C6-C60 aryloxy group” as used herein indicates ═OA102 (wherein A102 is the C6-C60 aryl group), and the term “C6-C60 arylthio group” as used herein indicates —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 is group, and A107 may be a C1-C59 heteroaryl group).
The term “R10a ” as used herein refers to:
deuterium (—D), —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, or a nitro group,
a C1-C60 alkyl group, a Cz-C60 alkenyl group, a Cz-C60 alkynyl group, or a C1-C60 alkoxy group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C7-C60 aryl alkyl group, a C2-C60 heteroaryl alkyl group, —Si(Q11)(Q12)(Q13), —N(Q11)(Q12), —B(Q11)(Q12), —C(═O)(Q11), —S(═O)2(Q11), —P(═O)(Q11)(Q12), or any combination thereof;
a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C7-C60 arylalkyl group, or a C2-C60 heteroarylalkyl group, each unsubstituted or substituted with deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C7-C60 aryl alkyl group, a C2-C60 heteroaryl alkyl group, —Si(Q21)(Q22)(Q23), —N(Q21)(Q22), —B(Q21)(Q22), —C(═O)(Q21), —S(═O)2(Q21), —P(═O)(Q21)(Q22), or any combination thereof; or
—Si(Q31)(Q32)(Q33), —N(Q31)(Q32), —B(Q31)(Q32), —C(═O)(Q31), —S(═O)2(Q31), or —P(═O)(Q31)(Q32).
The variables Q1 to Q3, Q11 to Q13, Q21 to Q23 and Q31 to Q33 as herein may each independently be: hydrogen; deuterium; —F; —Cl; —Br; —I; a hydroxyl group; a cyano group; a nitro group; a C1-C60 alkyl group; a C2-C60 alkenyl group; a C2-C60 alkynyl group; a C1-C60 alkoxy group; a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C7-C60 aryl alkyl group, or a is C2-C60 heteroaryl alkyl group, each unsubstituted or substituted with deuterium, —F, a cyano group, a C1-C60 alkyl group, a C1-C60 alkoxy group, a phenyl group, a biphenyl group, or any combination thereof.
The term “heteroatom” as used herein refers to any atom other than a carbon atom. Examples of the heteroatom are O, S, N, P, Si, B, Ge, Se, and any combination thereof.
The term “the third-row transition metal” used herein includes hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), or the like
As used herein, the term “Ph” refers to a phenyl group, the term “Me” refers to a methyl group, the term “Et” refers to an ethyl group, the term “ter-Bu” or “But” refers to a tert-butyl group, and the term “OMe” refers to a methoxy group.
The term “biphenyl group” as used herein refers to a “phenyl group substituted with a phenyl group.” In other words, the “biphenyl group” is 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”. In other words, the “terphenyl group” is a substituted phenyl group having, as a substituent, a C6-C60 aryl group substituted with a C6-C60 aryl group.
The symbols * and *′ as used herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula.
Hereinafter, compounds made according to the principles and illustrative embodiments of the invention and light-emitting devices including the same will be described in detail with reference to the following examples.
Manufacture of Light-Emitting Device
A glass/ITO (substrate) of 1200 Å (anode) was cut to a size of 50 mm×50 mm×0.7 mm, cleaned by sonication with isopropyl alcohol and pure water each for 5 minutes, and then cleaned by irradiation of ultraviolet rays and exposure of ozone thereto for 30 minutes, and then loaded into a vacuum deposition apparatus.
After plasma treatment of ITO of the substrate, the compound HT1 was vacuum deposited to a thickness of 1300 Å to form a hole transport layer. The compound 4,4′-bis(N-carbazolyl)-1,1′-biphenyl (CBP) as a host and the compound DPAVBi as a dopant were simultaneously deposited on the host transport layer in a weight ratio of 97:3 to form an emission layer having a thickness of 200 Å. The compound ET1 was deposited on the emission layer to a thickness of 300 Å to form an electron transport layer.
The element Yb was vacuum-deposited on the electron transport layer to a thickness of 15 Å, and consecutively, the alloy AgMg was vacuum-deposited thereon to a thickness of 100 Å to form a cathode, and the compound CP1 was deposited to form a capping layer having a thickness of 700 Å, thereby manufacturing a light-emitting device.
A light-emitting device was manufactured in the same manner as in Comparative Example 1, except that tungsten trioxide (WO3), instead of ITO, was used as the anode.
A light-emitting device was manufactured in the same manner as in Comparative Example 1, except that Compound 1, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 1, except that Compound 100, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 1, except that Compound 200, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 1, except that Compound 300, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 2, except that the plasma treatment of the anode was not performed and Compound 1, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 2, except that the plasma treatment of the anode was not performed and Compound 2, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 2, except that the plasma treatment of the anode was not performed and Compound 3, is instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 2, except that the plasma treatment of the anode was not performed and Compound 4, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 2, except that the plasma treatment of the anode was not performed and Compound 5, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 2, except that the plasma treatment of the anode was not performed and Compound 6, instead of the compound HT1, was used in the hole transport layer.
A light-emitting device was manufactured in the same manner as in Comparative Example 2, except that the plasma treatment of the anode was not performed and Compound 7, instead of the compound HT1, was used in the hole transport layer.
To evaluate the characteristics of the light-emitting devices manufactured according to Comparative Examples 1 to 6 and Examples 1 to 7, the driving voltage, efficiency, and lifespan at a current density of 10 milliamp per centimeter squared (mA/cm2) were measured.
The driving voltage and current density of the light-emitting devices were measured using a source meter (sold under the trade designation Keithley Instruments Inc., 2400 series, by Tektronix, Inc., of Beaverton, Oreg.), and the efficiency was measured using a luminescence efficiency measurement apparatus sold under the trade designation C9920-2-12 of Hamamatsu Photonics Inc. of Hamamatsu-city, Japan. The luminance and efficiency can be expressed in candela per meter squared and abbreviated cd/m2 or cd/A. The half lifespan is the time it takes to achieve 50% of the initial luminance measured in hour (hr) at 100 mA/cm2.
Table 1 shows that the light-emitting devices of Examples 1 to 7 exhibited significantly and unexpectedly excellent results in terms of efficiency and lifespan, as compared with the light-emitting devices of Comparative Examples 1 to 6. As described above, light-emitting devices constructed according to the principles and illustrative embodiments of the invention may exhibit reduced driving voltage, and improved efficiency and lifespan, as compared with the related art.
Although certain embodiments and implementations have been described herein, other embodiments and modifications will be apparent from this description. Accordingly, the inventive concepts are not limited to such embodiments, but rather to the broader scope of the appended claims and various obvious modifications and equivalent arrangements as would be apparent to a person of ordinary skill in the art.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2021-0056770 | Apr 2021 | KR | national |
