This application claims priority to and benefits of Korean Patent Application No. 10-2023-0190334 under 35 U.S.C. § 119, filed on Dec. 22, 2023, in the Korean Intellectual Property Office, the entire contents of which are incorporated herein by reference.
Embodiments relate 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 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.
In a light-emitting device, a first electrode may be arranged on a substrate, and a hole transport region, an emission layer, an electron transport region, and a second electrode may be 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.
It is to be understood that this background of the technology section is, in part, intended to provide useful background for understanding the technology. However, this background of the technology section may also include ideas, concepts, or recognitions that were not part of what was known or appreciated by those skilled in the pertinent art prior to a corresponding effective filing date of the subject matter disclosed herein.
Embodiments include a light-emitting device having improved efficiency, a long lifespan, and low capacitance, and an electronic apparatus including the light-emitting device.
Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the embodiments of the disclosure.
According to embodiments, a light-emitting device may include:
In an embodiment, the first electrode may be an anode; the second electrode may be a cathode; the interlayer may further include a hole transport region between the first electrode and the emission layer; and the hole transport region may include a hole injection layer, a hole transport layer, an electron-blocking layer, or any combination thereof.
In an embodiment, the first electrode may be an anode; the second electrode may be a cathode; the interlayer may further include an electron transport region between the second electrode and the emission layer; and the electron transport region may include a hole-blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.
In an embodiment, the first host may be a hole-transporting host.
In an embodiment, the second host may be an electron-transporting host.
In an embodiment, the first host may include one of the following moieties:
In an embodiment, the first host may include one of Compounds HT-1 to HT-40, which are explained below.
In an embodiment, the second host may include one of the following moieties:
In an embodiment, the second host may include one of Compounds ET-1 to ET-43, which are explained below.
In an embodiment, the metal may include a transition metal.
In an embodiment, the first dopant may include a compound represented by Formula 401, which is explained below.
In an embodiment, the first dopant may include a compound represented by Formula 1, which is explained below.
In an embodiment, in Formula 1, L1 may be one of the following functional groups:
In an embodiment, a substitution position of Si(R501)(R502)(R503) substituted in L1 and a substitution position of L1 substituted in the imidazole moiety may be on a straight line.
In an embodiment, in Formula 1, L1 may be phenylene substituted with R10a, and the substitution position of R10a may be at an ortho position to the imidazole moiety.
In an embodiment, the first dopant may include one of Compounds PD-1 to PD-20, which are explained below.
In an embodiment, the second dopant may include a compound represented by Formula 2, which is explained below.
In an embodiment, a capacitance of the light-emitting device may be less than or equal to about 6.8 nF, and the capacitance may refer to a capacitance value that is measured according to an applied voltage by using impedance spectroscopy and being a value measured at 1 kHz and 100 mV intervals.
According to embodiments, an electronic apparatus may include the light-emitting device.
It is to be understood that the embodiments above are described in a generic and explanatory sense only and not for the purpose of limitation, and the disclosure is not limited to the embodiments described above.
The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification.
The drawings illustrate embodiments of the disclosure and principles thereof. The above and other aspects and features of the disclosure will become more apparent by describing in detail embodiments thereof with reference to the accompanying drawings, in which:
The disclosure will now be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. This disclosure may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
In the drawings, the sizes, thicknesses, ratios, and dimensions of the elements may be exaggerated for ease of description and for clarity. Like reference numbers and/or like reference characters refer to like elements throughout.
In the description, it will be understood that when an element (or region, layer, part, etc.) is referred to as being “on”, “connected to”, or “coupled to” another element, it can be directly on, connected to, or coupled to the other element, or one or more intervening elements may be present therebetween. In a similar sense, when an element (or region, layer, part, etc.) is described as “covering” another element, it can directly cover the other element, or one or more intervening elements may be present therebetween.
In the description, when an element is “directly on,” “directly connected to,” or “directly coupled to” another element, there are no intervening elements present. For example, “directly on” may mean that two layers or two elements are disposed without an additional element such as an adhesion element therebetween.
As used herein, the expressions used in the singular such as “a,” “an,” and “the,” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, “A and/or B” may be understood to mean “A, B, or A and B.” The terms “and” and “or” may be used in the conjunctive or disjunctive sense and may be understood to be equivalent to “and/or”.
In the specification and the claims, the term “at least one of” is intended to include the meaning of “at least one selected from the group consisting of” for the purpose of its meaning and interpretation. For example, “at least one of A, B, and C” may be understood to mean A only, B only, C only, or any combination of two or more of A, B, and C, such as ABC, ACC, BC, or CC. When preceding a list of elements, the term, “at least one of,” modifies the entire list of elements and does not modify the individual elements of the list.
It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element.
Thus, a first element could be termed a second element without departing from the teachings of the disclosure. Similarly, a second element could be termed a first element, without departing from the scope of the disclosure.
The spatially relative terms “below”, “beneath”, “lower”, “above”, “upper”, or the like, may be used herein for ease of description to describe the relations between one element or component and another element or component as illustrated in the drawings. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation, in addition to the orientation depicted in the drawings. For example, in the case where a device illustrated in the drawing is turned over, the device positioned “below” or “beneath” another device may be placed “above” another device. Accordingly, the illustrative term “below” may include both the lower and upper positions. The device may also be oriented in other directions and thus the spatially relative terms may be interpreted differently depending on the orientations.
The terms “about” or “approximately” as used herein is inclusive of the stated value and means within an acceptable range of deviation for the recited value as determined by one of ordinary skill in the art, considering the measurement in question and the error associated with measurement of the recited quantity (i.e., the limitations of the measurement system). For example, “about” may mean within one or more standard deviations, or within ±20%, ±10%, or ±5% of the stated value.
It should be understood that the terms “comprises,” “comprising,” “includes,” “including,” “have,” “having,” “contains,” “containing,” and the like are intended to specify the presence of stated features, integers, steps, operations, elements, components, or combinations thereof in the disclosure, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.
Unless otherwise defined or implied herein, all terms (including technical and scientific terms) used have the same meaning as commonly understood by those skilled in the art to which this disclosure pertains. It will be further understood that 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 ideal or excessively formal sense unless clearly defined in the specification.
Embodiments provide a light-emitting structure having high efficiency, long lifespan, and low capacitance.
According to embodiments, a light-emitting device may include
In an embodiment, the first electrode may be an anode,
In an embodiment, the first electrode may be an anode,
In an embodiment, the first host may be a hole-transporting host.
In an embodiment, the second host may be an electron-transporting host.
The hole-transporting host may be a compound having strong hole properties. The expression “a compound having strong hole properties” refers to a compound that readily accepts holes, and such properties may be obtained by including a hole-receiving moiety (also, referred to as a HT moiety).
Examples of a HT moiety may include a π-electron-rich heteroaromatic compound (e.g., a carbazole derivative or an indole derivative), or an aromatic amine compound.
The electron-transporting host may be a compound having strong electron properties. The expression “a compound having strong electron properties” refers to a compound that accepts electrons, and such properties may be obtained by including an electron-receiving moiety (also, referred to as an ET moiety).
Examples of an ET moiety may include a π electron-deficient heteroaromatic compound. For example, the ET moiety may include a nitrogen-containing heteroaromatic compound.
When a compound includes only a HT moiety or only an ET moiety, it is clear whether the nature of the compound has HT properties or ET properties.
In an embodiment, a compound may include both a HT moiety and an ET moiety. In this regard, a simple comparison between the total number of the HT moieties and the total number of the ET moieties in the compound can be a criterion for predicting whether the compound a HT compound or an ET compound, but may not be an absolute criterion. One of the reasons why such a simple comparison cannot be an absolute criterion is that the hole attracting ability of one HT moiety and the electron attracting ability of one ET moiety may not have exactly the same magnitude as each other.
Accordingly, a relatively reliable way to determine whether a compound having a certain structure is HT or ET is to implement (e.g., directly implement) the compound in a device.
In an embodiment, the first host may include one of the following moieties:
In an embodiment, the first host may include one of Compounds HT-1 to HT-40:
In an embodiment, the second host may include one of the following moieties:
In an embodiment, the second host may include one of Compounds ET-1 to ET-43:
In an embodiment, a weight ratio of the first host to the second host may be in a range of about 9:1 to about 1:9. For example, a weight ratio of the first host to the second host may be in a range of about 6:4 to about 4:6. When the weight ratio of the first host to the second host is within any of these ranges, a balance of injected charges may be at an appropriate level.
According to an embodiment, the metal may include a transition metal.
In an embodiment, the first dopant may include a compound represented by Formula 401:
In Formulae 401 and 402,
Q11 to Q13, Q21 to Q23, Q31 to Q33, Q411 to Q414, and Q401 to Q403 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; or a C3-C60 carbocyclic group, a C1-C60 heterocyclic group, a C7-C60 arylalkyl group, or a C2-C60 heteroarylalkyl 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 a combination thereof,
In Formulae 401 and 402, when R401 includes a triarylsilyl group, both xc11 and xc12 may not be 0 at the same time.
According to an embodiment, the first dopant may include a compound represented by Formula 1:
In Formula 1,
According to an embodiment, in Formula 1, L1 may be one of the following functional groups:
According to an embodiment, in Formula 1, a substitution position of Si(R501)(R502)(R503) substituted in L1 and a substitution position of L1 substituted in the imidazole moiety may be on a straight line.
For example, L1 in Formula 1 may be phenylene, and a substitution position of Si(R501)(R502)(R503) may be at a para position to the imidazole moiety.
In the first dopant, which may be a compound represented by Formula 1, when the substitution position of Si(R501)(R502)(R503) substituted in L1 and the substitution position of L1 substituted in the imidazole moiety are on a straight line, the properties of a light-emitting device may be excellent. For example, the capacitance of the light-emitting device may be relatively low.
According to an embodiment, in Formula 1, L1 may be phenylene substituted with R10a, and the substitution position of R10a may be at an ortho position to the imidazole moiety.
In the first dopant, which may be a compound represented by Formula 1, L1 may be phenylene substituted with R10a, and when the substitution position of R10a is at an ortho position to the imidazole moiety, the properties of the light-emitting device may be excellent. For example, the capacitance of the light-emitting device may be relatively low.
In an embodiment, the first dopant may include one of Compounds PD-1 to PD-20:
According to an embodiment, the second dopant may include a compound represented by Formula 2:
In Formula 2,
According to an embodiment, the second dopant may include one of Compounds TD-1 to TD-36:
According to an embodiment, a capacitance of the light-emitting device may be less than or equal to about 6.8 nF. The capacitance may refer to a capacitance value that is measured according to the applied voltage using impedance spectroscopy, and may be a value measured at 1 kHz and 100 mV intervals. In an embodiment, the emission layer of the light-emitting device may include the first host, the second host, the first dopant, and the second dopant, and the capacitance may be less than or equal to about 6.8 nF.
In an embodiment, the emission layer may be a fluorescent emission layer.
In an embodiment, the emission layer may be a blue emission layer.
In an embodiment, an electronic apparatus may include a thin-film transistor, and the light-emitting device, wherein
The term “an organic layer” as used herein may be a single layer and/or all layers between the first electrode and the second electrode of the light-emitting device. A material included in the “organic layer” may not be limited to an organic material.
Hereinafter, the structure of the light-emitting device 10 according to an embodiment and a method of manufacturing the light-emitting device 10 will be described with reference to
In
The first electrode 110 may be formed by, for example, depositing or sputtering a material for forming the first electrode 110 on the substrate. When the first electrode 110 is an anode, a material for forming the first electrode 110 may be a high-work function material that facilitates injection of holes.
The first electrode 110 may be a reflective electrode, a semi-transmissive electrode, or a transmissive electrode. In an embodiment, when the first electrode 110 is a transmissive electrode, a material for forming the first electrode 110 may include indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO2), zinc oxide (ZnO), or any combination thereof. In embodiments, when the first electrode 110 is a semi-transmissive electrode or a reflective electrode, a material for forming the first electrode 110 may include magnesium (Mg), silver (Ag), aluminum (Al), aluminum-lithium (Al—Li), calcium (Ca), magnesium-indium (Mg—In), magnesium-silver (Mg—Ag), or any combination thereof.
The first electrode 110 may have a structure consisting of a single layer or a structure including multiple layers. For example, the first electrode 110 may have a three-layer structure of ITO/Ag/ITO.
The interlayer 130 is arranged on the first electrode 110. The interlayer 130 may include the emission layer.
The interlayer 130 may further include a hole transport region between the first electrode 110 and the emission layer, and an electron transport region between the emission layer and the second electrode 150.
The interlayer 130 may further include, in addition to various organic materials, a metal-containing compound such as an organometallic compound, an inorganic material such as quantum dots, or the like.
In an embodiment, the interlayer 130 may include two or more emitting units stacked between the first electrode 110 and the second electrode 150, and at least one charge generation layer which may be between adjacent units among the two or more emitting units. When the interlayer 130 includes the two or more emitting units and the at least one charge generation layer, the light-emitting device 10 may be a tandem light-emitting device.
The hole transport region may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a structure including multiple layers including different materials.
The hole transport region may include a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron-blocking layer, or any combination thereof.
In an embodiment, the hole transport region may have a multi-layer structure including a hole injection layer/hole transport layer structure, a hole injection layer/hole transport layer/emission auxiliary layer structure, a hole injection layer/emission auxiliary layer structure, a hole transport layer/emission auxiliary layer structure, or a hole injection layer/hole transport layer/electron-blocking layer structure, wherein the constituent layers of each structure may be stacked sequentially from the first electrode 110 in its respective stated order, but the structure of the hole transport region is not limited thereto.
The hole transport region may include a compound represented by Formula 201, a compound represented by Formula 202, or any combination thereof:
In Formulae 201 and 202,
In an embodiment, the compound represented by Formula 201 and the compound represented by Formula 202 may each independently include at least one of groups represented by Formulae CY201 to CY217:
In Formulae CY201 to CY217, R10b and R10c may each independently be the same as described in connection with 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 embodiments, in Formulae 201 to 217 ring CY201 to ring CY204 may each independently be a benzene group, a naphthalene group, a phenanthrene group, or an anthracene group.
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may include at least one of groups represented by Formulae CY201 to CY203.
In embodiments, the compound represented by 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 embodiments, in Formula 201, xa1 may be 1, R201 may be one of the groups represented by Formulae CY201 to CY203, xa2 may be 0, and R202 may be one of groups represented by Formulae CY204 to CY207.
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include groups represented by Formulae CY201 to CY203.
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include groups represented by Formulae CY201 to CY203, and may each independently include at least one of groups represented by Formulae CY204 to CY217.
In embodiments, the compound represented by Formula 201 and the compound represented by Formula 202 may each not include groups represented by Formulae CY201 to CY217.
In an embodiment, the hole transport region may include one of Compounds HT1 to HT46, m-MTDATA, TDATA, 2-TNATA, NPB(NPD), βNPB, TPD, spiro-TPD, spiro-NPB, methylated NPB, TAPC, 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:
A thickness of the hole transport region may be in a range of about 50 Å to about 10,000 Å. For example, the thickness of the hole transport region may be in a range of about 100 Å to about 4,000 Å. When the hole transport region includes a hole injection layer, a hole transport layer, or any combination thereof, a thickness of the hole injection layer may be in a range of about 100 Å to about 9,000 Å, and a thickness of the hole transport layer may be in a range of about 50 Å to about 2,000 Å. For example, the thickness of the hole injection layer may be in a range of about 100 Å to about 1,000 Å. For example, the thickness of the hole transport layer may be in a range of about 100 Å to about 1,500 Å. When the thicknesses of the hole transport region, the hole injection layer, and the hole transport layer are within any of these ranges, satisfactory hole transporting 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 a 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.
[p-Dopant]
The hole transport region may further include, in addition to these materials, a charge-generation material for the improvement of conductive properties. The charge-generation material may be uniformly or non-uniformly dispersed in the hole transport region (for example, in the form of a single layer consisting of a charge-generation material).
The charge-generation material may be, for example, a p-dopant.
For example, the p-dopant may have a lowest unoccupied molecular orbital (LUMO) energy level less than or equal to about −3.5 eV.
In an embodiment, the p-dopant may include a quinone derivative, a cyano group-containing compound, a compound including element EL1 and element EL2, or any combination thereof.
Examples of a quinone derivative may include TCNQ, F4-TCNQ, and the like.
Examples of a cyano group-containing compound may include HAT-CN, a compound represented by Formula 221, and the like:
In Formula 221,
In the compound including element EL1 and element EL2, element EL1 may be a metal, a metalloid, or any combination thereof, and element EL2 may be a non-metal, a metalloid, or any combination thereof.
Examples of a metal may include an alkali metal (for example, lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), etc.); an alkaline earth metal (for example, beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), etc.); a transition metal (for example, titanium (Ti), zirconium (Zr), hafnium (Hf), vanadium (V), niobium (Nb), tantalum (Ta), chromium (Cr), molybdenum (Mo), tungsten (W), manganese (Mn), technetium (Tc), rhenium (Re), iron (Fe), ruthenium (Ru), osmium (Os), cobalt (Co), rhodium (Rh), iridium (Ir), nickel (Ni), palladium (Pd), platinum (Pt), copper (Cu), silver (Ag), gold (Au), etc.); a post-transition metal (for example, zinc (Zn), indium (In), tin (Sn), etc.); a lanthanide metal (for example, lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), etc.); and the like.
Examples of a metalloid may include silicon (Si), antimony (Sb), tellurium (Te), and the like.
Examples of a non-metal may include oxygen (O), halogen (for example, F, Cl, Br, I, etc.), and the like.
Examples of a compound including element EL1 and element EL2 may include a metal oxide, a metal halide (for example, a metal fluoride, a metal chloride, a metal bromide, a metal iodide, etc.), a metalloid halide (for example, a metalloid fluoride, a metalloid chloride, a metalloid bromide, a metalloid iodide, etc.), a metal telluride, or any combination thereof.
Examples of a metal oxide may include a tungsten oxide (for example, WO, W2O3, WO2, WO3, W2O5, etc.), a vanadium oxide (for example, VO, V2O3, VO2, V2O5, etc.), a molybdenum oxide (MoO, Mo2O3, MoO2, MoO3, Mo2O5, etc.), a rhenium oxide (for example, ReO3, etc.), and the like.
Examples of a metal halide may include an alkali metal halide, an alkaline earth metal halide, a transition metal halide, a post-transition metal halide, a lanthanide metal halide, and the like.
Examples of an alkali metal halide may include LiF, NaF, KF, RbF, CsF, LiCl, NaCl, KCl, RbCl, CsCl, LiBr, NaBr, KBr, RbBr, CsBr, Lil, NaI, KI, RbI, CsI, and the like.
Examples of an alkaline earth metal halide may include BeF2, MgF2, CaF2, SrF2, BaF2, BeCl2, MgCl2, CaCl2), SrCl2, BaCl2, BeBr2, MgBr2, CaBr2, SrBr2, BaBr2, BeI2, MgI2, CaI2, SrI2, BaI2, and the like.
Examples of a transition metal halide may include a titanium halide (for example, TiF4, TiCl4, TiBr4, TiI4, etc.), a zirconium halide (for example, ZrF4, ZrCl4, ZrBr4, ZrI4, etc.), a hafnium halide (for example, HfF4, HfCl4, HfBr4, HfI4, etc.), a vanadium halide (for example, VF3, VCl3, VBr3, VI3, etc.), a niobium halide (for example, NbF3, NbCl3, NbBr3, NbI3, etc.), a tantalum halide (for example, TaF3, TaCl3, TaBr3, TaI3, etc.), a chromium halide (for example, CrF3, CrO3, CrBr3, CrI3, etc.), a molybdenum halide (for example, MoF3, MoCl3, MoBr3, MoI3, etc.), a tungsten halide (for example, WF3, WCl3, WBr3, WI3, etc.), a manganese halide (for example, MnF2, MnCl2, MnBr2, MnI2, etc.), a technetium halide (for example, TcF2, TcCl2, TcBr2, TcI2, etc.), a rhenium halide (for example, ReF2, ReCl2, ReBr2, ReI2, etc.), an iron halide (for example, FeF2, FeCl2, FeBr2, FeI2, etc.), a ruthenium halide (for example, RuF2, RuCl2, RuBr2, RuI2, etc.), an osmium halide (for example, OsF2, OsCl2, OsBr2, OsI2, etc.), a cobalt halide (for example, CoF2, COCl2, CoBr2, COI2, etc.), a rhodium halide (for example, RhF2, RhCl2, RhBr2, RhI2, etc.), an iridium halide (for example, IrF2, IrCl2, IrBr2, IrI2, etc.), a nickel halide (for example, NiF2, NiCl2, NiBr2, NiI2, etc.), a palladium halide (for example, PdF2, PdCl2, PdBr2, PdI2, etc.), a platinum halide (for example, PtF2, PtCl2, PtBr2, PtI2, etc.), a copper halide (for example, CuF, CuCl, CuBr, CuI, etc.), a silver halide (for example, AgF, AgCl, AgBr, AgI, etc.), a gold halide (for example, AuF, AuCl, AuBr, AuI, etc.), and the like.
Examples of a post-transition metal halide may include a zinc halide (for example, ZnF2, ZnCl2, ZnBr2, ZnI2, etc.), an indium halide (for example, InI3, etc.), a tin halide (for example, SnI2, etc.), and the like.
Examples of a lanthanide metal halide may include YbF, YbF2, YbF3, SmF3, YbCl, YbCl2, YbCl3 SmCl3, YbBr, YbBr2, YbBr3 SmBr3, YbI, YbI2, YbI3, and SmI3.
Examples of a metalloid halide may include an antimony halide (for example, SbCl5, etc.) and the like.
Examples of a metal telluride may include an alkali metal telluride (for example, Li2Te, Na2Te, K2Te, Rb2Te, Cs2Te, etc.), an alkaline earth metal telluride (for example, BeTe, MgTe, CaTe, SrTe, BaTe, etc.), a transition metal telluride (for example, TiTe2, ZrTe2, HfTe2, V2Te3, Nb2Te3, Ta2Te3, Cr2Te3, Mo2Te3, W2Te3, MnTe, TcTe, ReTe, FeTe, RuTe, OsTe, CoTe, RhTe, IrTe, NiTe, PdTe, PtTe, Cu2Te, CuTe, Ag2Te, AgTe, Au2Te, etc.), a post-transition metal telluride (for example, ZnTe, etc.), a lanthanide metal telluride (for example, LaTe, CeTe, PrTe, NdTe, PmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, etc.), and the like.
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 a subpixel. In an embodiment, the emission layer may have a stacked structure of two or more layers of a red emission layer, a green emission layer, and a blue emission layer, in which the two or more layers may contact each other or may be separated from each other, to emit white light. In embodiments, the emission layer may include two or more materials of a red light-emitting material, a green light-emitting material, and a blue light-emitting material, in which the two or more materials may be mixed with each other in a single layer, to emit white light.
In an embodiment, the emission layer may include a host and a dopant. The dopant may include a phosphorescent dopant, a fluorescent dopant, or any combination thereof.
An amount of the dopant in the emission layer may be in a range of about 0.01 parts by weight to about 15 parts by weight, based on 100 parts by weight of the host.
In embodiments, the emission layer may include a quantum dot.
In embodiments, the emission layer may include a delayed fluorescence material. The delayed fluorescence material may serve as a host or as a dopant in the emission layer.
A thickness of the emission layer may be in a range of about 100 Å to about 1,000 Å. For example, the thickness of the emission layer may be in a range of about 200 Å to about 600 Å. When the thickness of the emission layer is within any of these ranges, excellent luminescence characteristics may be obtained without a substantial increase in driving voltage.
The host may include a first host and a second host.
The host may further include, for example, in addition to the first host and the second host, a compound represented by Formula 301:
[Formula 301]
[Ar301]xb11-[(L301)xb1-R301]xb21
In Formula 301,
In an embodiment, in Formula 301, when xb11 is 2 or more, two or more of Ar301 may be linked to each other via a single bond.
In 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,
In embodiments, the host may include an alkali earth metal complex, a post-transition metal complex, or any combination thereof. In embodiments, the host may include a Be complex (for example, Compound H55), an Mg complex, a Zn complex, or any combination thereof.
In embodiments, the host may include one of Compounds H1 to H128, 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-9-carbazolylbenzene (mCP), 1,3,5-tri(carbazol-9-yl)benzene (TCP), or any combination thereof:
In an embodiment, the first dopant may include a phosphorescent dopant.
According to an embodiment, an amount of the first dopant may be in a range of about 1.0 wt % to about 30 wt %, based on 100 parts by weight of the total host. When the amount of the first dopant is within the range above, the light-emitting device may have excellent efficiency and lifespan.
In an embodiment, the emission layer may include a delayed fluorescence material.
In an embodiment, the second dopant may include a delayed fluorescence material.
In an embodiment, an amount of the second dopant may be in a range of about 1.0 wt % to about 7.0 wt %, based on 100 parts by weight of the total host. When the amount of the second dopant is within the range above, the light-emitting device may have excellent efficiency and lifespan.
The electron transport region may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a structure including multiple 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.
In an embodiment, the electron transport region may have an electron transport auxiliary layer/electron transport layer structure, an electron transport auxiliary layer/electron transport layer/electron injection layer structure, or the like, wherein the layers of each structure may be stacked from the emission layer in its respective stated order, but the structure of the electron transport region is not limited thereto.
In an embodiment, the electron transport region (e.g., a buffer layer, a hole-blocking layer, an electron control layer, or an electron transport layer in the electron transport region) may include a metal-free compound including at least one π electron-deficient nitrogen-containing C1-C60 cyclic group.
In an embodiment, the electron transport region may include a compound represented by Formula 601:
[Formula 601]
[Ar601]xe11-[(L601)xe1-R601]xe21
In Formula 601,
In an embodiment, in Formula 601, when xe11 is 2 or more, two or more of Ar601 may be linked to each other via a single bond.
In an embodiment, in Formula 601, Ar601 may be a substituted or unsubstituted anthracene group.
In embodiments, the electron transport region may include a compound represented by Formula 601-1:
In Formula 601-1,
In an embodiment, in Formula 601 and 601-1, xe1 and xe611 to xe613 may each independently be 0, 1, or 2.
In an embodiment, 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); Alq3; BAlq; TAZ; NTAZ, or any combination thereof:
A thickness of the electron transport region may be in a range of about 100 Å to about 5,000 Å. For example, the thickness of the electron transport region may be in a range of about 160 Å to about 4,000 Å. When the electron transport region includes a hole-blocking layer, an electron transport layer, or any combination thereof, a thickness of the hole-blocking layer or the electron transport layer may each independently be in a range of about 20 Å to about 1,000 Å. For example, the thickness of the hole blocking layer or the electron transport layer may each independently be in a range of about 30 Å to about 300 Å. A thickness of the electron transport layer may be in a range of about 100 Å to about 1,000 Å. For example, the thickness of the electron transport layer may be in a range of about 150 Å to about 500 Å. When the thicknesses of the hole-blocking layer and/or the electron transport layer are within any of 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. A metal ion of an alkali metal complex may be a L1 ion, a Na ion, a K ion, a Rb ion, or a Cs ion, and a 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 a metal ion of the alkali metal complex or with a metal ion of an 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 L1 complex. The L1 complex may include, for example, Compound ET-D1 (LiQ) or Compound 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 contact (e.g., directly contact) the second electrode 150.
The electron injection layer may have a structure consisting of a layer consisting of a single material, a structure consisting of a layer including different materials, or a structure including multiple 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, iodides, etc.), 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: an alkali metal oxide, such as Li2O, Cs2O, K2O, and the like; an alkali metal halide, such as LiF, NaF, CsF, KF, Lil, NaI, CsI, KI, and the like; 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 0<x<1), BaxCa1-xO (wherein x is a real number satisfying 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 an embodiment, the rare earth metal-containing compound may include a lanthanide metal telluride. Examples of a lanthanide metal telluride may include LaTe, CeTe, PrTe, NdTe, PmTe, SmTe, EuTe, GdTe, TbTe, DyTe, HoTe, ErTe, TmTe, YbTe, LuTe, La2Te3, Ce2Te3, Pr2Te3, Nd2Te3, Pm2Te3, Sm2Te3, Eu2Te3, Gd2Te3, Tb2Te3, Dy2Te3, Ho2Te3, Er2Te3, Tm2Te3, Yb2Te3, Lu2Te3, and the like.
The alkali metal complex, the alkaline earth-metal complex, and the rare earth metal complex may include an alkali metal ion, an alkaline earth metal ion, or a rare earth metal ion, and a ligand bonded to the metal ion (for example, hydroxyquinoline, hydroxyisoquinoline, hydroxybenzoquinoline, hydroxyacridine, hydroxyphenanthridine, hydroxyphenyloxazole, hydroxyphenylthiazole, hydroxyphenyloxadiazole, hydroxyphenylthiadiazole, hydroxyphenylpyridine, hydroxyphenyl benzimidazole, hydroxyphenylbenzothiazole, bipyridine, phenanthroline, cyclopentadiene, or a combination thereof).
In an embodiment, the electron injection layer may consist of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal-containing compound, an alkaline earth metal-containing compound, a rare earth metal-containing compound, an alkali metal complex, an alkaline earth metal complex, a rare earth metal complex, or any combination thereof, as described above. In embodiments, the electron injection layer may further include an organic material (for example, a compound represented by Formula 601).
In an embodiment, the electron injection layer may consist of an alkali metal-containing compound (for example, alkali metal halide); or the electron injection layer may consist of an alkali metal-containing compound (for example, an alkali metal halide), and 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, a LiF:Yb co-deposited layer, and 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 uniformly or non-uniformly dispersed in a matrix including the organic material.
A thickness of the electron injection layer may be in a range of about 1 Å to about 100 Å. For example, the thickness of the electron injection layer may be in a range of about 3 Å to about 90 Å. When the thickness of the electron injection layer is within any of these ranges, satisfactory electron injection characteristics may be obtained without a substantial increase in driving voltage.
The second electrode 150 is arranged on the interlayer 130 having the aforementioned structure. The second electrode 150 may be a cathode, which is an electron injection electrode. When the second electrode 150 is a cathode, a material for forming the second electrode 150 may include a material having low-work function, such as a metal, an alloy, an electrically conductive compound, or any combination thereof.
The second electrode 150 may include Li, Ag, Mg, Al, Al—Li, Ca, Mg—In, Mg—Ag, Yb, Ag—Yb, ITO, 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-layer structure or a multi-layer structure.
The light-emitting device 10, may include a first capping layer outside the first electrode 110, and/or a second capping layer outside the second electrode 150. For example, 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 stacked in this stated order, a structure in which the first electrode 110, the interlayer 130, the second electrode 150, and the second capping layer are stacked in this 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 stacked in this stated order.
Light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted through the first electrode 110, which may be a semi-transmissive electrode or a transmissive electrode, and through the first capping layer to the outside. Light generated in the emission layer of the interlayer 130 of the light-emitting device 10 may be extracted through the second electrode 150, which may be a semi-transmissive electrode or a transmissive electrode, and through the second capping layer to the outside.
The first capping layer and the second capping layer may each 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.
The first capping layer and the second capping layer may each include a material having a refractive index of greater than or equal to about 1.6 (with respect to a wavelength of about 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 a carbocyclic compound, a heterocyclic compound, an amine group-containing compound, a porphine derivative, a phthalocyanine derivative, a naphthalocyanine derivative, an alkali metal complex, an alkaline earth metal complex, or a combination thereof. The carbocyclic compound, the heterocyclic compound, and the amine group-containing compound may each be optionally substituted with a substituent including O, N, S, Se, Si, F, Cl, Br, I, or any combination thereof.
In an embodiment, at least one of the first capping layer and the second capping layer may each independently include an amine group-containing compound.
In 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 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, βNPB, or any combination thereof:
The light-emitting device may be included in various electronic apparatuses. For example, an electronic apparatus including the light-emitting device may be a light-emitting apparatus, an authentication apparatus, and the like.
The electronic apparatus (for example, a light-emitting apparatus) may further include, in addition to the light-emitting device, a color filter, a color conversion layer, or a color filter and a color conversion layer. The color filter and/or the color conversion layer may be arranged in at least one traveling direction of light emitted from the light-emitting device. For example, the light emitted from the light-emitting device may be blue light or white light. The light-emitting device may be a light-emitting device as described herein. In an embodiment, the color conversion layer may include a quantum dot.
The electronic apparatus may include a first substrate. The first substrate may include subpixels, the color filter may include color filter areas respectively corresponding to the subpixels, and the color conversion layer may include color conversion areas respectively corresponding to the subpixels.
A pixel-defining film may be arranged between the subpixels to define each subpixel.
The color filter may further include color filter areas and light-shielding patterns arranged between the color filter areas, and the color conversion layer may further include color conversion areas and light-shielding patterns arranged between 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 third color light, wherein 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. In an embodiment, the color filter areas (or the color conversion areas) may include quantum dots. In an embodiment, 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. The quantum dot may be a quantum dot as described herein. The first area, the second area, and/or the third area may each further include a scatterer.
In an embodiment, the light-emitting device 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 an embodiment, the first-first color light, the second-first color light, and the third-first color light may have different maximum emission wavelengths from one another. In an embodiment, 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 as described above. The thin-film transistor may include a source electrode, a drain electrode, and an active layer, wherein one of the source electrode and the drain electrode may be electrically connected to one of the first electrode and the second electrode of the light-emitting device.
The thin-film transistor may further include a gate electrode, a gate insulating film, and the like.
The active layer may include crystalline silicon, amorphous silicon, an organic semiconductor, an oxide semiconductor, and the like.
The electronic apparatus may further include a sealing portion for sealing the light-emitting device. The sealing portion may be arranged between the color filter and/or the color conversion layer and the light-emitting device. The sealing portion may allow light from the light-emitting device to be extracted to the outside, and may prevent ambient air and moisture from penetrating into the light-emitting device. 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 that includes 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 further included on the sealing portion, in addition to the color filter and/or the color conversion layer, according to the use of the electronic apparatus. Examples of a 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, etc.).
The authentication apparatus may further include, in addition to the light-emitting device as described above, a biometric information collector.
The electronic apparatus may 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 instruments, meters (for example, meters for a vehicle, an aircraft, and a vessel), projectors, and the like.
The electronic apparatus of
The substrate 100 may be a flexible substrate, a glass substrate, or a metal substrate. A buffer layer 210 may be arranged on the substrate 100. The buffer layer 210 may prevent penetration of impurities through the substrate 100 and may provide a flat surface on the substrate 100.
A TFT may be arranged on the buffer layer 210. The TFT may include an active layer 220, a gate electrode 240, a source electrode 260, and a drain electrode 270.
The active layer 220 may include an inorganic semiconductor, such as silicon or 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 active layer 220 from the gate electrode 240 may be arranged on the active layer 220, and the gate electrode 240 may be arranged on the gate insulating film 230.
An interlayer insulating film 250 may be arranged on the gate electrode 240. The interlayer insulating film 250 may be arranged between the gate electrode 240 and the source electrode 260 to insulate the gate electrode 240 from the source electrode 260 and between the gate electrode 240 and the drain electrode 270 to insulate the gate electrode 240 from the drain electrode 270.
The source electrode 260 and the drain electrode 270 may be arranged on the interlayer insulating film 250. The interlayer insulating film 250 and the gate insulating film 230 may be formed to expose a source region and a drain region of the active layer 220, and the source electrode 260 and the drain electrode 270 may respectively contact the exposed portions of the source region and the drain region of the active layer 220.
The TFT may be electrically connected to a light-emitting device to drive the light-emitting device, and may be covered and protected by a passivation layer 280. The passivation layer 280 may include an inorganic insulating film, an organic insulating film, or any combination thereof. A light-emitting device may be provided on the passivation layer 280. The light-emitting device may include the first electrode 110, the interlayer 130, and the second electrode 150.
The first electrode 110 may be arranged on the passivation layer 280. The passivation layer 280 may not completely cover the drain electrode 270 and may expose a portion of the drain electrode 270. The first electrode 110 may be electrically connected to the exposed portion of the drain electrode 270.
A pixel defining layer 290 including an insulating material may be arranged on the first electrode 110. The pixel defining layer 290 may expose a region of the first electrode 110, and an interlayer 130 may be formed on the exposed region of the first electrode 110. The pixel defining layer 290 may be a polyimide-based organic film or a polyacrylic-based organic film. Although not shown in
The second electrode 150 may be arranged on the interlayer 130, and a capping layer 170 may be further included on the second electrode 150. The capping layer 170 may be formed to cover the second electrode 150.
The encapsulation portion 300 may be arranged on the capping layer 170. The encapsulation portion 300 may be arranged on a light-emitting device to protect the light-emitting device from moisture and/or oxygen. The encapsulation portion 300 may include: an inorganic film including silicon nitride (SiNx), silicon oxide (SiOx), indium tin oxide, indium zinc oxide, or any combination thereof; an organic film including polyethylene terephthalate, polyethylene naphthalate, polycarbonate, polyimide, polyethylene sulfonate, polyoxymethylene, polyarylate, hexamethyldisiloxane, an acrylic resin (for example, polymethyl methacrylate, polyacrylic acid, or the like), an epoxy-based resin (for example, 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 of
The layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region may be formed in a selected region by using various methods such as vacuum deposition, spin coating, casting, Langmuir-Blodgett (LB) deposition, ink-jet printing, laser-printing, laser-induced thermal imaging, and the like.
When the layers constituting the hole transport region, the emission layer, and the layers constituting the electron transport region are formed by vacuum deposition, the deposition may be performed at a deposition temperature in a range of about 100° C. to about 500° C., at a vacuum degree in a range of about 10−8 torr to about 10−3 torr, and at a deposition speed in a range of about 0.01 Å/sec to about 100 Å/sec, depending on a material to be included in a layer to be formed and the structure of a layer to be formed.
The term “C3-C60 carbocyclic group” as used herein may be a cyclic group consisting of carbon atoms as the only ring-forming atoms and having three to sixty carbon atoms. The term “C1-C60 heterocyclic group” as used herein may be a cyclic group that has one to sixty carbon atoms and further has, in addition to carbon atoms, at least one heteroatom as a ring-forming atom. 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 condensed with each other. For example, the number of ring-forming atoms of the C1-C60 heterocyclic group may be from 3 to 61.
The “cyclic group” as used herein may be a C3-C60 carbocyclic group or a C1-C60 heterocyclic group.
The term “π electron-rich C3-C60 cyclic group” as used herein may be a cyclic group that has three to sixty carbon atoms and may not include *—N═*′ as a ring-forming moiety. The term “π electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein may be a heterocyclic group that has one to sixty carbon atoms and may include *—N═*′ as a ring-forming moiety.
In an embodiment,
A 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 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 terms “cyclic group”, “C3-C60 carbocyclic group”, “C1-C60 heterocyclic group”, “π electron-rich C3-C60 cyclic group”, and “π electron-deficient nitrogen-containing C1-C60 cyclic group” as used herein may each be a group condensed to any cyclic group, a monovalent group, or a polyvalent group (for example, a divalent group, a trivalent group, a tetravalent group, etc.) according to the structure of a formula for which the corresponding term is used. For example, a “benzene group” may be a benzo group, a phenyl group, a phenylene group, or the like, which may be readily understood by one of ordinary skill in the art according to the structure of a formula including the “benzene group.”
Examples of a monovalent C3-C60 carbocyclic group or a monovalent C1-C60 heterocyclic group may include a C3-C10 cycloalkyl group, a C1-C60 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C60 heterocycloalkenyl group, a C6-C60 aryl group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent condensed heteropolycyclic group. Examples of a divalent C3-C60 carbocyclic group or a divalent C1-C60 heterocyclic group may include a C3-C10 cycloalkylene group, a C1-C10 heterocycloalkylene group, a C3-C10 cycloalkenylene group, a C1-C10 heterocycloalkenylene group, a C6-C60 arylene group, a C1-C60 heteroarylene group, a divalent non-aromatic condensed polycyclic group, and a divalent non-aromatic condensed heteropolycyclic group.
The term “C1-C60 alkyl group” as used herein may be a linear or branched monovalent aliphatic hydrocarbon group that has one to sixty carbon atoms, and examples thereof may include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, an n-pentyl group, a tert-pentyl group, a neopentyl group, an isopentyl group, a sec-pentyl group, a 3-pentyl group, a sec-isopentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, an n-heptyl group, an isoheptyl group, a sec-heptyl group, a tert-heptyl group, an n-octyl group, an isooctyl group, a sec-octyl group, a tert-octyl group, an n-nonyl group, an isononyl 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 may be a divalent group having a same structure as the C1-C60 alkyl group.
The term “C2-C60 alkenyl group” as used herein may be a monovalent hydrocarbon group having at least one carbon-carbon double bond in the middle or at a terminus of a C2-C60 alkyl group, and examples thereof may include an ethenyl group, a propenyl group, a butenyl group, and the like. The term “C2-C60 alkenylene group” as used herein may be a divalent group having a same structure as the C2-C60 alkenyl group.
The term “C2-C60 alkynyl group” as used herein may be a monovalent hydrocarbon group having at least one carbon-carbon triple bond in the middle or at a terminus of a C2-C60 alkyl group, and examples thereof are an ethynyl group, a propynyl group, and the like. The term “C2-C60 alkynylene group” as used herein may be a divalent group having a same structure as the C2-C60 alkynyl group.
The term “C1-C60 alkoxy group” as used herein may be a monovalent group represented by —O(A101) (wherein A101 may be a C1-C60 alkyl group), and examples thereof may include a methoxy group, an ethoxy group, an isopropyloxy group, and the like.
The term “C3-C10 cycloalkyl group” as used herein may be a monovalent saturated hydrocarbon cyclic group having 3 to 10 carbon atoms, and examples thereof may include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, an adamantyl group, a norbornyl group (or bicyclo[2.2.1]heptyl group), a bicyclo[1.1.1]pentyl group, a bicyclo[2.1.1]hexyl group, a bicyclo[2.2.2]octyl group, and the like. The term “C3-C10 cycloalkylene group” as used herein may be a divalent group having a same structure as the C3-C10 cycloalkyl group.
The term “C1-C1 heterocycloalkyl group” as used herein may be a monovalent cyclic group having 1 to 10 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms, and examples thereof may include a 1,2,3,4-oxatriazolidinyl group, a tetrahydrofuranyl group, a tetrahydrothiophenyl group, and the like. The term “C1-C1 heterocycloalkylene group” as used herein may be a divalent group having a same structure as the C1-C1 heterocycloalkyl group.
The term “C3-C10 cycloalkenyl group” as used herein may be a monovalent cyclic group that has three to ten carbon atoms and at least one carbon-carbon double bond in the cyclic structure thereof and no aromaticity, and examples thereof may include a cyclopentenyl group, a cyclohexenyl group, a cycloheptenyl group, and the like. The term “C3-C10 cycloalkenylene group” as used herein may be a divalent group having a same structure as the C3-C10 cycloalkenyl group.
The term “C1-C1 heterocycloalkenyl group” as used herein may be a monovalent cyclic group of 1 to 10 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms, and having at least one carbon-carbon double bond in the cyclic structure thereof. Examples of a C1-C10 heterocycloalkenyl group may include a 4,5-dihydro-1,2,3,4-oxatriazolyl group, a 2,3-dihydrofuranyl group, a 2,3-dihydrothiophenyl group, and the like. The term “C1-C10 heterocycloalkenylene group” as used herein may be a divalent group having a same structure as the C1-C60 heterocycloalkenyl group.
The term “C6-C60 aryl group” as used herein may be a monovalent group having a carbocyclic aromatic system of 6 to 60 carbon atoms, and the term “C6-C60 arylene group” as used herein may be a divalent group having a carbocyclic aromatic system of 6 to 60 carbon atoms. Examples of a C6-C60 aryl group may include a phenyl group, a pentalenyl group, a naphthyl group, an azulenyl group, an indacenyl group, an acenaphthyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyrenyl group, a chrysenyl group, a perylenyl group, a pentaphenyl group, a heptalenyl group, a naphthacenyl group, a picenyl group, a hexacenyl group, a pentacenyl group, a rubicenyl group, a coronenyl group, an ovalenyl group, and the like. When the C6-C60 aryl group and the C6-C60 arylene group each include two or more rings, the respective rings may be condensed with each other.
The term “C1-C60 heteroaryl group” as used herein may be a monovalent group having a heterocyclic aromatic system of 1 to 60 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms. The term “C1-C60 heteroarylene group” as used herein may be a divalent group having a heterocyclic aromatic system of 1 to 60 carbon atoms, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms. Examples of a C1-C60 heteroaryl group may include a pyridinyl group, a pyrimidinyl group, a pyrazinyl group, a pyridazinyl group, a triazinyl group, a quinolinyl group, a benzoquinolinyl group, an isoquinolinyl group, a benzoisoquinolinyl group, a quinoxalinyl group, a benzoquinoxalinyl group, a quinazolinyl group, a benzoquinazolinyl group, a cinnolinyl group, a phenanthrolinyl group, a phthalazinyl group, and a naphthyridinyl group. When the C1-C60 heteroaryl group and the C1-C60 heteroarylene group each include two or more rings, the respective rings may be condensed with each other.
The term “monovalent non-aromatic condensed polycyclic group” as used herein may be a monovalent group (for example, having 8 to 60 carbon atoms) having two or more rings condensed to each other, only carbon atoms as ring-forming atoms, and no aromaticity in its molecular structure as a whole. Examples of a monovalent non-aromatic condensed polycyclic group may include an indenyl group, a fluorenyl group, a spiro-bifluorenyl group, a benzofluorenyl group, an indenophenanthrenyl group, an indeno anthracenyl group, and the like. The term “divalent non-aromatic condensed polycyclic group” as used herein may be a divalent group having a same structure as the monovalent non-aromatic condensed polycyclic group described above.
The term “monovalent non-aromatic condensed heteropolycyclic group” as used herein may be a monovalent group (for example, having 1 to 60 carbon atoms) having two or more rings condensed to each other, further including, in addition to carbon atoms, at least one heteroatom as ring-forming atoms, and having no aromaticity in its molecular structure as a whole. Examples of a monovalent non-aromatic condensed heteropolycyclic group may include a pyrrolyl group, a thiophenyl group, a furanyl group, an indolyl group, a benzoindolyl group, a naphthoindolyl group, an isoindolyl group, a benzoisoindolyl group, a naphthoisoindolyl group, a benzosilolyl group, a benzothiophenyl group, a benzofuranyl group, a carbazolyl group, a dibenzosilolyl group, a dibenzothiophenyl group, a dibenzofuranyl group, an azacarbazolyl group, an azafluorenyl group, an azadibenzosilolyl group, an azadibenzothiophenyl group, an azadibenzofuranyl group, a pyrazolyl group, an imidazolyl group, a triazolyl group, a tetrazolyl group, an oxazolyl group, an isoxazolyl group, a thiazolyl group, an isothiazolyl group, an oxadiazolyl group, a thiadiazolyl group, a benzopyrazolyl group, a benzimidazolyl group, a benzoxazolyl group, a benzothiazolyl group, a benzoxadiazolyl group, a benzothiadiazolyl group, an imidazopyridinyl group, an imidazopyrimidinyl group, an imidazotriazinyl group, an imidazopyrazinyl group, an imidazopyridazinyl group, an indenocarbazolyl group, an indolocarbazolyl group, a benzofurocarbazolyl group, a benzothienocarbazolyl group, a benzosilolocarbazolyl group, a benzoindolocarbazolyl group, a benzocarbazolyl group, a benzonaphthofuranyl group, a benzonaphthothiophenyl group, a benzonaphthosilolyl group, a benzofurodibenzofuranyl group, a benzofurodibenzothiophenyl group, and a benzothienodibenzothiophenyl group. The term “divalent non-aromatic condensed heteropolycyclic group” as used herein may be a divalent group having a same structure as the monovalent non-aromatic condensed heteropolycyclic group described above.
The term “C6-C60 aryloxy group” as used herein may be a group represented by —O(A102) (wherein A102 may be a C6-C60 aryl group), and the term “C6-C60 arylthio group” as used herein may be a group represented by —S(A103) (wherein A103 may be a C6-C60 aryl group).
The term “C7-C60 arylalkyl group” as used herein may be a group represented by -(A104)(A105) (wherein A104 may be a C1-C54 alkylene group, and A105 may be a C6-C59 aryl group), and the term “C2-C60 heteroarylalkyl group” as used herein may be a group represented by -(A106)(A107) (wherein A106 may be a C1-C59 alkylene group, and A107 may be a C1-C59 heteroaryl group).
In the specification, the group “R10a” may be:
In the specification, the groups 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; or a C1-C60 alkoxy group; or
The term “heteroatom” as used herein may be any atom other than a carbon atom or a hydrogen atom. Examples of a heteroatom may include O, S, N, P, Si, B, Ge, Se, and any combination thereof.
The term “the third-row transition metal” as used herein may be hafnium (Hf), tantalum (Ta), tungsten (W), rhenium (Re), osmium (Os), iridium (Ir), platinum (Pt), gold (Au), etc.
In the specification, 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 terms “tert-Bu” and “But” each refer to a tert-butyl group, and the term “OMe” refers to a methoxy group.
The term “biphenyl group” as used herein may be a “phenyl group substituted with a phenyl group.” For example, a “biphenyl group” may be a substituted phenyl group having a C6-C60 aryl group as a substituent.
The term “terphenyl group” as used herein may be a “phenyl group substituted with a biphenyl group.” For example, the “terphenyl group” may be a substituted phenyl group having, as a substituent, a C6-C60 aryl group substituted with a C6-C60 aryl group.
The maximum number of carbon atoms as described in the definitions above are only examples. For example, the maximum carbon number of 60 in a C1-C60 alkyl group is only an example, and the definition of the alkyl group may also be applied to a C1-C20 alkyl group. The same may apply to the definitions of other groups as described above.
The symbols * and *′ as used herein, unless defined otherwise, each refer to a binding site to a neighboring atom in a corresponding formula.
As an anode, a Corning 15 Ω/cm2 (1,200 Å) ITO glass substrate was cut to a size of 50 mm×50 mm×0.5 mm, sonicated with isopropyl alcohol and pure water each for 10 minutes, and subjected to a plasma treatment. The ITO glass substrate was provided to a vacuum deposition apparatus.
Compound m-MTDATA was vacuum-deposited on the substrate to form a hole injection layer having a thickness of 100 Å, and HT3 was vacuum-deposited thereon to form a hole transport layer having a thickness of 600 Å.
Compound HT-39, which is the first host, Compound ET-38, which is the second host, Compound PD-1, which is the first dopant, and Compound TD-28, which is the second dopant, were co-deposited on the hole transport layer to form a emission layer having a thickness of 400 Å (first host:second host=6:4 (weight ratio), first dopant=10 wt %, second dopant=1 wt %).
As a compound for an electron transport layer, ETL1 and lithium quinoline were co-deposited at a weight ratio of 5:5 to form an electron transport layer having a thickness of 300 Å.
Ytterbium (Yb) was deposited to a thickness of 10 Å on the electron transport layer to form an electron injection layer, and MgAg was vacuum deposited to a thickness of 3000 Å on the electron injection layer at a weight ratio of 90:10 to form a cathode, thereby completing the manufacture of a light-emitting device.
Light-emitting devices were manufactured in the same manner as in Example 1, except that the compounds shown in Table 1 were used as the first host compound, second host compound, the first dopant compound, and the second dopant compound when forming the emission layer.
A light-emitting device was manufactured in the same manner as in Example 1, except that 3,3′-di(9H-carbazol-9-yl)-1,1′-biphenyl (mCBP), which is a host, Compound 100, which is the first dopant, and Compound 200, which is the second host, were used when forming the emission layer. The amount of the host is the sum of the amount of the first host and the amount of the second host in Example 1.
A light-emitting device was manufactured in the same manner as in Example 1, except that Compound 300 was used as the first dopant and Compound 200 was used as the second dopant when forming the emission layer.
A light-emitting device was manufactured in the same manner as in Example 1, except that Compound 400 was used as the first dopant and Compound 200 was used as the second dopant when forming the emission layer.
A light-emitting device was manufactured in the same manner as Example 1, except that only Compound 500 was used as a dopant when forming the emission layer. The amount of the dopant is the sum of the amount of the first dopant and the amount of the second dopant of Example 1.
The measurements of the efficiency, lifespan, and capacitance of the light-emitting devices are shown in Table 1. The luminescence efficiency (Cd/A) and lifespan of the light-emitting devices at 1000 cd/mm2 were measured using Keithley MU 236 and luminance meters SR3AR and PR650. The lifespan corresponds to a time it took for the luminance to reach 90% of the initial luminance. Capacitance was measured at 1 kHz and 100 mV intervals according to the applied voltage using impedance spectroscopy [model: Dielectric Impedance Measurement System from Novocontrol Inc.].
From Table 1, it can be seen that light-emitting devices of the Examples show excellent properties compared to the light-emitting devices of the Comparative Examples.
A light-emitting device according to an embodiment may have excellent efficiency, lifespan, and capacitance.
Embodiments have been disclosed herein, and although terms are employed, they are used and are to be interpreted in a generic and descriptive sense only and not for purposes of limitation. In some instances, as would be apparent by one of ordinary skill in the art, features, characteristics, and/or elements described in connection with an embodiment may be used singly or in combination with features, characteristics, and/or elements described in connection with other embodiments unless otherwise specifically indicated. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope of the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2023-0190334 | Dec 2023 | KR | national |