Organic light emitting diode comprising an organic semiconductor layer

Abstract

This invention relates to an organic light-emitting diode (OLED) comprising an organic semiconductor layer. The OLED includes an anode, a cathode, a first emitter layer, a second emitter layer, at least one organic semiconductor layer disposed between the first and second emitter layers, and a p-type charge-generating layer. The organic semiconductor layer comprises a rare-earth metal dopant selected from Sm, Eu, and Yb, and a first matrix compound, and is disposed between and in direct contact with the p-type charge-generating layer. The first matrix compound comprises at least two phenanthroline groups. The p-type charge-generating layer comprises an axialene dopant and a matrix, or is composed of an axialene dopant and a matrix. The OLED exhibits improved operating voltage, external quantum efficiency, and / or voltage rise over time.

Description

[0001] This application is a divisional application of the application filed on May 31, 2017, with Chinese national application number 201710397438.1 and the invention title "Organic Light Emitting Diode Containing an Organic Semiconductor Layer". Technical Field

[0002] The present invention relates to an organic light-emitting diode (OLED) comprising an organic semiconductor layer containing a compound of formula 1, and also to a method of manufacturing the organic light-emitting diode (OLED) comprising the organic semiconductor layer. Background Technology

[0003] Organic light-emitting diodes (OLEDs) are self-emissive devices with wide viewing angles, excellent contrast, fast response, high brightness, excellent driving voltage characteristics, and color reproduction. A typical OLED comprises an anode, a hole injection layer (HIL), a hole transport layer (HTL), an emitter layer (EML), an electron transport layer (ETL), and a cathode, sequentially stacked on a substrate. In this context, the HIL, HTL, EML, and ETL are thin films formed from organic compounds.

[0004] When a voltage is applied to the anode and cathode, holes injected from the anode move to the EML via the HIL and HTL, while electrons injected from the cathode move to the EML via the ETL. The holes and electrons recombine in the EML to generate excitons.

[0005] The semiconductor layer contained in organic light-emitting diodes (OLEDs) in the art can be formed by depositing an organic matrix material together with a metal dopant such as Cs or Li. However, these prior art OLEDs may suffer from poor performance. Furthermore, poor control of the evaporation rate of the metal dopant is a significant problem when fabricating these OLEDs. Specifically, the doping concentration of Li is very low and therefore difficult to control. In addition, safe handling of the metal dopant is highly desirable when loading the vacuum thermal evaporation (VTE) source and when opening the evaporation chamber for maintenance.

[0006] EP 2 833 429 A1 discloses an organic electroluminescent device comprising, in sequence, an anode, one or more organic thin film layers including an emitting layer, a donor layer, an acceptor layer, and a highly transmissive cathode, wherein the donor layer comprises a compound represented by formula (I) or (II) below:

[0007]

[0008] JP2008243932 discloses an organic electroluminescent element. In the organic electroluminescent element, an anode, a light-emitting functional layer, and a transparent cathode are stacked sequentially. The electroluminescent element has an electron transport layer made of an organic material using general formula (1), which is located between the light-emitting layer and the cathode. The cathode has a first layer containing an alkali metal element, a group II element, or a rare earth element in a transparent conductive material. In general formula (1), A represents a substituent having a phenanthroline skeleton or a benzoquinone skeleton, (n) represents a natural number of 2 or greater, and B represents at least one selected from a benzene ring, a substituent having a terphenyl skeleton, and a naphthalene ring. When B represents a benzene ring, all A's contain at least one of an alkyl group and an aryl group in the skeleton. Summary of the Invention

[0009] Therefore, the object of the present invention is to provide an organic light-emitting diode comprising a metal-doped organic semiconductor layer, which overcomes the shortcomings of the prior art, particularly having improved operating voltage, external quantum efficiency, and / or voltage rise over time. Furthermore, the object of the present invention is to provide a metal dopant suitable for manufacturing OLEDs, which has reduced air sensitivity and good control over its evaporation rate.

[0010] This objective is achieved by an organic light-emitting diode comprising an anode, a cathode, at least one emitting layer and at least one organic semiconductor layer, wherein the at least one emitting layer and at least one organic semiconductor layer are disposed between the anode and the cathode, and the organic semiconductor layer comprises a rare earth metal dopant that is substantially metallic and a first matrix compound comprising at least two phenanthroline groups, preferably two to four phenanthroline groups.

[0011] On the other hand, an organic light-emitting diode is provided, comprising an anode, a cathode, at least one emitting layer and at least one organic semiconductor layer, wherein the at least one emitting layer and the at least one organic semiconductor layer are disposed between the anode and the cathode, and the organic semiconductor layer is composed of a substantially metallic rare earth metal dopant and a first matrix compound, the first matrix compound comprising at least two phenanthroline groups, preferably two to four phenanthroline groups.

[0012] Preferably, the first matrix compound is a substantially organic compound. More preferably, the first matrix compound has a molar mass of 450 to 1100 grams per mole.

[0013] The term "substantially organic" should be understood to encompass compounds that contain the elements C, H, N, O, S, B, P, or Si and do not contain metals.

[0014] More preferably, the phenanthrolinyl group is included in the first matrix compound via a trivalent carbon atom adjacent to one of the two nitrogen atoms contained in the phenanthrolinyl group.

[0015] Preferably, the first matrix compound is a compound of Formula 1:

[0016]

[0017] Where R 1 To R 7 Each is independently selected from: hydrogen, substituted or unsubstituted C6 to C6. 18 aryl, substituted or unsubstituted pyridyl, substituted or unsubstituted quinolinyl, substituted or unsubstituted C1 to C1 16 Alkyl, substituted or unsubstituted C1 to C 16 alkoxy, hydroxy or carboxyl, and / or the corresponding R group therein. 1 To R 7 Adjacent groups may bond to each other to form a ring;

[0018] L 1 It is a single key or selected from: C6 to C 30 Alpha-aryl, C5 to C 30 Heteroaryl, C1 to C8 alkylene or C1 to C8 alkoxyalkylene;

[0019] Ar 1 It is substituted or unsubstituted C6 to C 18 aryl or pyridyl; and

[0020] n is an integer from 2 to 4, where each of the n phenanthroline groups in parentheses may be the same as or different from each other.

[0021] When used herein, the term "alkyl" should encompass both straight-chain and branched and cyclic alkyl groups. For example, C3-alkyl groups may be selected from n-propyl and isopropyl. Similarly, C4-alkyl groups encompass n-butyl, sec-butyl, and tert-butyl. Likewise, C6-alkyl groups encompass n-hexyl and cyclohexyl.

[0022] C n The subscript number n in the text refers to the total number of carbon atoms in the corresponding alkyl, aryl, heteroaryl, or alkoxy group.

[0023] When used herein, the term "aryl" should encompass phenyl (C6-aryl), fused aromatic compounds such as naphthalene, anthracene, phenanthrene, and tetraphenyl, etc. It also encompasses biphenyl and oligomeric or polyphenylene such as terphenyl, etc. It should also encompass any other aromatic hydrocarbon substituents such as fluorene, etc. Aromaticyl refers to a group attached to two other components.

[0024] When used herein, the term "heteroaryl" refers to an aryl group in which at least one carbon atom is substituted by a heteroatom preferably selected from N, O, S, B, or Si. "Hypoaryl" refers to a group attached to two other constituent parts.

[0025] Similarly, when used herein, the term "alkoxy" refers to an alkoxy (-O-alkyl) group, wherein the alkyl group is as defined above.

[0026] C n - The subscript 'n' in a heteroaryl group refers only to the number of carbon atoms excluding heteroatoms. In this regard, it is clear that a C5 heteroaryl is an aromatic compound containing 5 carbon atoms, such as a pyridyl group.

[0027] According to the present invention, if the corresponding group is R 1 To R 7 L 1 and Ar 1 If substituted, the group may preferably be replaced by at least one C1 to C2 group. 12 Alkyl or C1 to C 12 Alkoxy, more preferably C1 to C4 alkyl or C1 to C4 alkoxy substitution. By suitably selecting the appropriate substituents, particularly the length of the hydrocarbon chain, the physical properties of the compound, such as its solubility in organic solvents or its evaporation rate, can be adjusted.

[0028] Furthermore, preferably, n is 2 or 3, more preferably 2.

[0029] In other preferred embodiments, L 1 It is a single key.

[0030] Preferably, Ar 1 It is a phenylene oxide.

[0031] More preferably, R 1 To R 7 Independently selected from: hydrogen, C1 to C4 alkyl, C1 to C4 alkoxy, C6 to C 12 Aryl and C5 to C 12 Heteroaryl groups, preferably selected from hydrogen, C1 to C4 alkyl groups and phenyl groups.

[0032] Preferably, the first matrix compound is selected from:

[0033]

[0034]

[0035]

[0036]

[0037] In this regard, in the most preferred case, the first matrix compound is

[0038]

[0039] For the purposes of this invention, rare earth elements or rare earth metals, as defined by IUPAC, are one of a group of 17 chemical elements in the periodic table, specifically 15 lanthanide elements as well as scandium and yttrium.

[0040] Preferably, the rare earth metal dopant of the substantially metallic substance is a zero-valent metal dopant, preferably selected from Sm, Eu, and Yb.

[0041] In this regard, the most preferred embodiment of the substantial metal is Yb as the rare earth metal dopant.

[0042] The term "substantially metallic" should be understood to encompass metals that at least partially take the form of a substantial element. The term "substantially elemental" should be understood to be a form that, in terms of electronic state and energy and in terms of the chemical bonds of the contained metal atoms, is closer to the form of an elemental metal or a free metal atom, or closer to the form of a cluster of metal atoms, than the form of a metal salt, organometallic compound, or another compound containing covalent bonds between a metal and a nonmetal, or the form of a coordination compound of a metal.

[0043] One benefit offered by rare earth metal dopants is the higher doping concentration, measured as a weight percentage, compared to alkali metals, and particularly lithium. This allows for better control over the evaporation rate and improved repeatability during manufacturing. Furthermore, rare earth metals are less sensitive to air and moisture than alkali and alkaline earth metals, making them safer for use in large-scale production. On the other hand, rare earth metal dopants are less prone to diffusion than alkali and alkaline earth metals. Therefore, stability over time, such as with increasing operating voltage, can be improved.

[0044] In another embodiment, the organic semiconductor layer is disposed between the emitter layer and the cathode. This improves electron injection and / or electron transport from the cathode to the emitter layer.

[0045] In other embodiments, the organic semiconductor layer is in direct contact with the cathode.

[0046] In another case, the organic light-emitting diode includes a first emission layer and a second emission layer, wherein an organic semiconductor layer is disposed between the first emission layer and the second emission layer.

[0047] In another embodiment, the organic light-emitting diode includes a first organic semiconductor layer and a second organic semiconductor layer, wherein the first organic semiconductor layer is disposed between the first and second emission layers, and the second organic semiconductor layer is disposed between the cathode and the emission layer closest to the cathode. Thus, excellent performance can be achieved when only the same compound is used in the n-type charge generation layer and the electron transport and / or electron injection layer.

[0048] In other embodiments, the organic light-emitting diode further includes a p-type charge-generating layer, wherein the organic semiconductor layer is disposed between the first emitting layer and the p-type charge-generating layer. This improves electron generation and transport between the first and second emitting layers.

[0049] In another embodiment, the organic semiconductor layer is in direct contact with the p-type charge generation layer.

[0050] Preferably, the organic semiconductor layer is not the cathode. The cathode is substantially metallic. Preferably, the cathode does not contain organic compounds.

[0051] In another embodiment, the at least one organic semiconductor layer is not in direct contact with the at least one emission layer. This reduces the quenching of light emission through the essentially metallic rare-earth metal dopants.

[0052] Preferably, the organic semiconductor layer is substantially non-emissive.

[0053] In the context of this specification, the term "substantially non-emissive" means that the contribution of the organic semiconductor layer to the visible light emission spectrum of the device is less than 10%, preferably less than 5%, relative to the visible light emission spectrum. The visible light emission spectrum is an emission spectrum having a wavelength of about ≥380 nm to about ≤780 nm.

[0054] In another embodiment, the organic light-emitting diode further includes an electron transport layer disposed between the at least one emitting layer and the at least one organic semiconductor layer.

[0055] In another embodiment, the cathode is transparent to visible light emission.

[0056] In this regard, the term "transparent" refers to the physical property of the material that allows at least 50%, preferably at least 80%, more preferably at least 90% of visible light emission to pass through.

[0057] In another embodiment, the anode and cathode may be transparent to visible light emission.

[0058] In another embodiment, the cathode comprises a first cathode layer and a second cathode layer.

[0059] In this regard, the first cathode layer and / or the second cathode layer can be obtained by depositing them using a sputtering process. Preferably, the second electrode is formed using a sputtering process.

[0060] Furthermore, the object of the present invention is achieved by a method for manufacturing the organic light-emitting diode of the present invention, the method comprising the following steps: sequentially forming an anode, at least one emission layer, at least one organic semiconductor layer and a cathode on a substrate, and forming the at least one organic semiconductor layer by co-depositing a substantially metallic rare earth metal dopant together with a first matrix compound comprising at least two phenanthroline groups, preferably two to four phenanthroline groups.

[0061] According to various embodiments of the organic light-emitting diode of the present invention, the thickness of the organic semiconductor layer can be in the range of about ≥5 nm to about ≤500 nm, preferably about ≥10 nm to about ≤200 nm.

[0062] If the cathode is deposited by a sputtering process, the thickness of the organic semiconductor layer is preferably in the range of ≥100 nm to ≤500 nm.

[0063] If the organic semiconductor layer is disposed between the first emitter layer and the p-type charge generation layer and / or between the emitter layer and the cathode, the thickness of the organic semiconductor layer is preferably in the range of about ≥5 nm to about ≤100 nm, more preferably in the range of about ≥5 nm to about ≤40 nm.

[0064] In this invention, the following terms are defined, and unless otherwise defined in the claims or elsewhere in this specification, these definitions shall apply.

[0065] In the context of this specification, the terms "different" or "different" when referring to matrix materials mean that the matrix materials differ in their structural formulas.

[0066] In the context of this specification, the terms "different" or "different" when referring to lithium compounds mean that the lithium compounds differ in their structural formulas.

[0067] The terms "free from", "does not contain", and "excluding" do not exclude impurities that may be present in the compound prior to deposition. Impurities have no technical impact on the objectives achieved by this invention.

[0068] Vacuum thermal evaporation, also known as VTE, describes the process of heating a compound in a VTE source and evaporating the compound from the VTE source under reduced pressure.

[0069] External quantum efficiency, also known as EQE, is measured as a percentage (%).

[0070] The lifetime between the initial luminance and 97% of the original luminance is also known as LT, and is measured in hours (h).

[0071] Operating voltage, also known as V, is at 10 milliamperes per square centimeter (mA / cm²). 2 Measurements are taken at 100°C and are expressed in volts (V).

[0072] The increase in voltage over time, also known as V rise, is at 30 milliamperes per square centimeter (mA / cm²). 2 ) and at a temperature of 85°C, measured in volts (V).

[0073] Color spaces are described using coordinates CIE-x and CIE-y (International Commission on Illumination 1931). CIE-y is particularly important for blue light emission; a smaller CIE-y indicates a deeper blue.

[0074] The highest occupied molecular orbital, also known as HOMO, and the lowest unoccupied molecular orbital, also known as LUMO, are measured in electron volts (eV).

[0075] The terms "OLED" and "organic electroluminescent device" and "organic light-emitting diode" are used together and have the same meaning.

[0076] When used herein, the terms "percentage by weight," "% by weight," and variations thereof express the composition of a component, substance, or reagent as the weight of that component, substance, or reagent in the corresponding electron transport layer divided by the total weight of the corresponding electron transport layer and multiplied by 100. It should be understood that the total weight percentage of all components, substances, and reagents in the corresponding organic semiconductor layer is chosen to not exceed 100% by weight.

[0077] When used herein, the terms "molar percentage," "molar %," and variations thereof express the composition of a component, substance, or reagent as a fraction of the molar mass of that component, substance, or reagent in the corresponding electron transport layer divided by the total molar mass of the corresponding electron transport layer and multiplied by 100. It should be understood that the total molar percentage of all components, substances, and reagents in the corresponding organic semiconductor layer is chosen to not exceed 100 molar %.

[0078] When used herein, the terms "volume percentage," "volume %," and variations thereof express the composition of a component, substance, or reagent as the volume of that component, substance, or reagent in the corresponding electron transport layer divided by the total volume of the corresponding electron transport layer and multiplied by 100. It should be understood that the total volume percentage of all components, substances, and reagents in the corresponding organic semiconductor layer is chosen to not exceed 100% by volume.

[0079] Whether explicitly stated or not, all numerical values ​​herein are assumed to be modified by the term “about.” When used herein, the term “about” refers to the variability that may occur in the numerical quantity. Whether or not modified by the term “about,” the claim includes equality with the quantity.

[0080] It should be noted that, when used in this specification and claims, the singular form includes the plural references, unless the context clearly states otherwise.

[0081] In this document, when a first element is referred to as being formed on or disposed on a second element, the first element may be directly disposed on the second element, or one or more other elements may be disposed therebetween. When a first element is referred to as being directly formed on or disposed on a second element, no other elements are disposed therebetween.

[0082] The term "contact sandwich" refers to a three-layer arrangement in which the middle layer is in direct contact with the two adjacent layers.

[0083] The anode and cathode can be described as anode / cathode or anode layer / cathode layer.

[0084] The organic light-emitting diode of the present invention may include the following components. In this regard, the corresponding components may be as follows.

[0085] substrate

[0086] The substrate can be any substrate commonly used in the manufacture of organic light-emitting diodes. If light emission passes through the substrate, the substrate can be a transparent material, such as a glass substrate or a transparent plastic substrate, which has excellent mechanical strength, thermal stability, transparency, surface smoothness, ease of handling, and water resistance. If light emission passes through the top surface, the substrate can be a transparent or opaque material, such as a glass substrate, a plastic substrate, a metal substrate, or a silicon substrate.

[0087] anode

[0088] The anode can be formed by deposition or sputtering of a compound used to form the anode. The compound used to form the anode can be a high work function compound to facilitate hole injection. The anode material can also be selected from low work function materials (i.e., aluminum). The anode can be a transparent or reflective electrode. Transparent conductive compounds such as indium tin oxide (ITO), indium zinc oxide (IZO), tin dioxide (SnO2), and zinc oxide (ZnO) can be used to form anode 120. Anode 120 can also be formed using magnesium (Mg), aluminum (Al), aluminum-lithium (Al-Li), calcium (Ca), magnesium-indium (Mg-In), magnesium-silver (Mg-Ag), silver (Ag), gold (Au), etc.

[0089] cathode

[0090] In other preferred embodiments, the cathode comprises at least one substantially metallic cathode layer containing a first zero-valent metal selected from alkali metals, alkaline earth metals, rare earth metals, group 3 transition metals, and mixtures thereof.

[0091] The term "substantially metallic" should be understood to encompass metals that at least partially take the form of a substantial element. The term "substantially elemental" should be understood to be a form that, in terms of electronic state and energy and in terms of the chemical bonds of the contained metal atoms, is closer to the form of an elemental metal or a free metal atom, or closer to the form of a cluster of metal atoms, than the form of a metal salt, organometallic compound, or another compound containing covalent bonds between a metal and a nonmetal, or the form of a coordination compound of a metal.

[0092] It should be understood that, apart from pure elemental metals, atomized metals, metal molecules, and metal clusters, metal alloys represent any other instance of metals in substantially elemental form. These exemplary representations of substantially metals are constituent components of the cathode layer of the substantially metal.

[0093] When the first zero-valent metal is selected from this group, exceptionally low operating voltages and high manufacturing yields can be obtained.

[0094] According to another aspect, an organic light-emitting diode is provided, wherein the substantially metallic cathode layer is free of metal halides and / or free of metal-organic compounds.

[0095] According to a preferred embodiment, the substantially metallic cathode layer comprises or is composed of the first zero-valent metal. In a particularly preferred embodiment, the substantially metallic cathode layer further comprises a second zero-valent metal, wherein the second zero-valent metal is selected from an O(n) metal or a transition metal; and wherein the second zero-valent metal is different from the first zero-valent metal.

[0096] More preferably, the second zero-valent metal is selected from Li, Na, K, Cs, Mg, Ca, Sr, Ba, Sc, Y, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Au, Al, Ga, In, Sn, Te, Bi, Pb and mixtures thereof; more preferably, the second zero-valent metal is selected from Ag, Au, Zn, Te, Yb, Ga, Bi, Ba, Ca, Al and mixtures thereof; most preferably, the second zero-valent metal is selected from Ag, Zn, Te, Yb, Ga, Bi and mixtures thereof.

[0097] When selected from this list, the second zero-valent metal can improve the reliability of the deposition process and the mechanical stability of the deposited layer, thereby increasing the manufacturing yield. Furthermore, the second zero-valent metal can increase the reflectivity of the first cathode layer.

[0098] According to another embodiment, the substantially metallic cathode layer may comprise at least about ≥15 vol% to about ≤99 vol% of the first zero-valent metal and less than about ≥85 vol% to about ≤1 vol% of the second zero-valent metal; preferably ≥15 vol% to about ≤95 vol% of the first zero-valent metal and less than about ≥85 vol% to about ≤5 vol% of the second zero-valent metal; more preferably ≥20 vol% to about ≤90 vol% of the first zero-valent metal and less than about ≥80 vol% to about ≤10 vol% of the second zero-valent metal; furthermore, preferably ≥15 vol% to about ≤80 vol% of the first zero-valent metal and less than about ≥85 vol% to about ≤20 vol% of the second zero-valent metal.

[0099] Particularly preferably, the substantially metallic cathode layer comprises at least about ≥20 vol% to about ≤85 vol% of the first zero-valent metal selected from Mg and less than about ≥80 vol% to about ≤15 vol% of the second zero-valent metal selected from Ag.

[0100] The first zero-valent metal enables efficient electron injection from the cathode. The second zero-valent metal can stabilize the cathode layer and / or improve the yield of the cathode deposition step and / or improve the transparency or reflectivity of the cathode.

[0101] In other embodiments, the cathode layer comprising the substantially metal in the cathode is a first cathode layer, and the cathode further comprises a second cathode layer, wherein the first cathode layer is arranged closer to the organic semiconductor layer, the second cathode layer is arranged further away from the organic semiconductor layer, and wherein the second cathode layer comprises at least one third metal in the form of a zero-valent metal, alloy, oxide, or mixture thereof, wherein the third metal is selected from group metals, transition metals, rare earth metals, or mixtures thereof, preferably the third metal is selected from zero-valent Ag, Al, Cu, Au, MgAg alloys, indium tin oxide, indium zinc oxide, ytterbium oxide, indium gallium zinc oxide, more preferably the third metal is selected from Ag, Al, or MgAg alloys, and most preferably the third metal is selected from zero-valent Ag or Al.

[0102] The second cathode layer can protect the first cathode layer from environmental damage. Furthermore, it can enhance the external coupling of light emission within the device when light is emitted through the cathode.

[0103] The thickness of the first cathode layer can be in the range of about 0.2 nm to 100 nm, preferably 1 to 50 nm. If there is no second cathode layer, the thickness of the first cathode layer can be in the range of 1 to 25 nm. If there is a second cathode layer, the thickness of the first cathode layer can be in the range of 0.2 to 5 nm.

[0104] The thickness of the second cathode layer can be in the range of 0.5 to 500 nm, preferably 10 to 200 nm, or even more preferably 50 to 150 nm.

[0105] When the thickness of the cathode is in the range of 5 nm to 50 nm, the cathode may be transparent, even if metal or metal alloy is used.

[0106] In other embodiments, the cathode comprises a transparent conductive oxide (TCO), a metal sulfide, and / or Ag, preferably indium tin oxide (ITO), indium zinc oxide (IZO), zinc sulfide, or Ag. ITO and Ag are most preferred. If the cathode contains these compounds, it may be transparent to visible light emission.

[0107] The thickness of the transparent cathode can be in the range of 5 to 500 nm. If the transparent cathode is made of transparent conductive oxide (TCO) or metal sulfide, the thickness of the transparent cathode can be selected in the range of 30 to 500 nm, preferably 50 to 400 nm, and even more preferably 70 to 300 nm. If the transparent cathode is made of Ag, the thickness of the transparent cathode can be selected in the range of 5 to 50 nm, preferably 5 to 20 nm.

[0108] Hole injection layer

[0109] The hole injection layer (HIL) 130 can be formed on the anode 120 by vacuum deposition, spin coating, printing, casting, slot extrusion coating, Langmuir-Blodgett (LB) deposition, etc. When HIL 130 is formed using vacuum deposition, the deposition conditions can vary depending on the compound used to form HIL 130 and the desired structure and thermal properties of HIL 130. However, generally, the conditions for vacuum deposition can include deposition temperatures from 100°C to 500°C and 10 -8 Up to 10 -3 The pressure was 1 Torr (1 Torr equals 133.322 Pa) and the deposition rate was 0.1 to 10 nm / sec.

[0110] When HIL 130 is formed using spin coating or printing, the coating conditions can vary depending on the compound used to form HIL 130 and the desired structure and thermal properties of HIL 130. For example, coating conditions may include a coating speed of about 2000 rpm to about 5000 rpm and a heat treatment temperature of about 80°C to about 200°C. After the coating is performed, heat treatment removes the solvent.

[0111] HIL 130 can be formed from any compound commonly used to form HTL. Examples of compounds that can be used to form HIL 130 include phthalocyanine compounds such as copper phthalocyanine (CuPc), 4,4′,4″-tris(3-methylphenylphenylamino)triphenylamine (m-MTDATA), TDATA, 2T-NATA, polyaniline / dodecylbenzenesulfonic acid (Pani / DBSA), poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate) (PEDOT / PSS), polyaniline / camphorsulfonic acid (Pani / CSA), and polyaniline / poly(4-styrenesulfonate) (PANI / PSS).

[0112] HIL 130 can be a pure p-doped layer or can be selected from: hole transport matrix compounds doped with p-doped agents. Typical examples of known redox-doped hole transport materials are: copper phthalocyanine (CuPc) with a HOMO level of approximately -5.2 eV, doped with tetrafluoro-tetracyanoquinone dimethyl ether (F4TCNQ) with a LUMO level of approximately -5.2 eV; zinc phthalocyanine (ZnPc) (HOMO = -5.2 eV), doped with F4TCNQ; α-NPD (N,N′-bis(naphthyl-1-yl)-N,N′-bis(phenyl)-benzidine) doped with F4TCNQ; α-NPD doped with 2,2′-(perfluoronaphthyl-2,6-diethylenediamine)dimalonitrile (PD1); and α-NPD doped with 2,2′,2″-(cyclopropane-1,2,3-triethylenediamine)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) (PD2). The dopant concentration can be selected from 1 to 20% by weight, more preferably 3% by weight to 10% by weight.

[0113] The thickness of HIL 130 can range from about 1 nm to about 100 nm, for example, from about 1 nm to about 25 nm. When the thickness of HIL 130 is within this range, HIL 130 may have excellent hole injection characteristics without a significant increase in driving voltage.

[0114] Hole transport layer

[0115] Hole transport layer (HTL) 140 can be formed on HIL 130 by vacuum deposition, spin coating, slot extrusion coating, printing, casting, Lambert-Brogue (LB) deposition, etc. When HTL 140 is formed by vacuum deposition or spin coating, the conditions used for deposition and coating can be similar to those used for forming HIL 130. However, the conditions used for vacuum or solution deposition can vary depending on the compound used to form HTL 140.

[0116] HTL 140 can be formed from any compound commonly used to form HTLs. Suitable compounds are disclosed, for example, in Yasuhiko Shirota and Hiroshi Kageyama, Chem. Rev. 2007, 107, 953-1010, which are incorporated herein by reference. Examples of compounds that can be used to form HTL 140 are: carbazole derivatives, such as N-phenylcarbazole or polyvinylcarbazole; amine derivatives having an aromatic fused ring, such as N,N′-bis(3-methylphenyl)-N,N′-diphenyl-[1,1-biphenyl]-4,4′-diamine (TPD) or N,N′-di(naphthyl-1-yl)-N,N′-diphenylbenzidine (α-NPD); and triphenylamine-based compounds, such as 4,4′,4″-tris(N-carbazolyl)triphenylamine (TCTA). In these compounds, TCTA can transport holes and inhibit exciton diffusion into the EML.

[0117] The thickness of HTL 140 can be in the range of about 5 nm to about 250 nm, preferably about 10 nm to about 200 nm, more preferably about 20 nm to about 190 nm, more preferably about 40 nm to about 180 nm, more preferably about 60 nm to about 170 nm, more preferably about 80 nm to about 160 nm, more preferably about 100 nm to about 160 nm, and more preferably about 120 nm to about 140 nm. The preferred thickness of HTL 140 can be from 170 nm to 200 nm.

[0118] When the thickness of HTL 140 is within this range, HTL 140 may have excellent hole transport characteristics without a significant increase in drive voltage.

[0119] Electron blocking layer

[0120] The electron blocking layer (EBL) 150 functions to prevent electrons from transferring from the emitter layer to the hole transport layer, thus confining electrons to the emitter layer. This improves efficiency, operating voltage, and / or lifetime. Typically, the electron blocking layer comprises a triarylamine compound. The triarylamine compound may have a LUMO level closer to the vacuum level than the LUMO level of the hole transport layer. The electron blocking layer may have a HOMO level further away from the vacuum level than the HOMO level of the hole transport layer. The thickness of the electron blocking layer is selected between 2 and 20 nm.

[0121] The electron blocking layer may comprise a compound of the following formula Z:

[0122]

[0123] In equation Z,

[0124] CY1 and CY2 may be the same as or different from each other, and each independently represents a benzene ring or a naphthalene ring.

[0125] Ar1 to Ar3 may be the same as or different from each other, and are each independently selected from: hydrogen, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, and substituted or unsubstituted heteroaryl groups having 5 to 30 carbon atoms.

[0126] Ar4 is selected from: substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted triphenylene, and substituted or unsubstituted heteroaryl groups having 5 to 30 carbon atoms.

[0127] L is a substituted or unsubstituted aryl group having 6 to 30 carbon atoms.

[0128] If an electron blocking layer has a high triplet energy level, it can also be described as a triplet control layer.

[0129] The function of the triplet control layer is to reduce triplet quenching if a green or blue phosphorescent emitting layer is used. This allows for higher luminous efficiency from the phosphorescent emitting layer. The triplet control layer is selected from triarylamine compounds having a triplet energy level higher than that of the phosphorescent emitter in the adjacent emitting layer. Suitable triplet control layers, particularly the triarylamine compounds, are described in EP 2 722 908 A1.

[0130] Emitting Layer (EML)

[0131] EML 150 can be formed on the HTL by vacuum deposition, spin coating, slot extrusion coating, printing, casting, LB, etc. When the EML is formed using vacuum deposition or spin coating, the conditions for deposition and coating can be similar to those for forming the HTL. However, the conditions for deposition and coating can vary depending on the compound used to form the EML.

[0132] The emitter layer (EML) can be formed from a combination of a matrix and a dopant. Examples of the matrix are Alq3, 4,4′-N,N′-dicarbazole-biphenyl (CBP), poly(n-vinylcarbazole) (PVK), 9,10-bis(naphthyl-2-yl)anthracene (AND), 4,4′,4″-tris(carbazole-9-yl)triphenylamine (TCTA), 1,3,5-tris(N-phenylbenzimidazol-2-yl)benzene (TPBI), 3-tert-butyl-9,10-bis-2-naphthylanthracene (TBADN), stilbeneylarylene (DSA), zinc bis(2-(2-hydroxyphenyl)benzothiazolic acid) (Zn(BTZ)2), E3 described below, compound 1 described below, and compound 2 described below.

[0133]

[0134]

[0135] The dopant can be a phosphorescent or fluorescent emitter. Phosphorescent emitters and emitters that emit light via thermally activated delayed fluorescence (TADF) are preferred due to their high efficiency. The emitter can be a small molecule or a polymer.

[0136] Examples of red light dopants include PtOEP, Ir(piq)3, and Btp2lr(acac), but are not limited to these.

[0137] These compounds are phosphorescent emitters, however, red fluorescent dopants can also be used.

[0138]

[0139] Examples of green phosphorescent dopants are Ir(ppy)3 (ppy = phenylpyridine), Ir(ppy)2 (acac), and Ir(mpyp)3, as shown below. Compound 3 is an example of a green fluorescent emitter, and its structure is shown below.

[0140]

[0141] Examples of blue phosphorescent dopants are F₂Irpic, (F₂ppy)₂Ir(tmd), and Ir(dfppz)₃, trifluorene, with structures shown below. 4,4′-bis(4-diphenylaminostyryl)biphenyl (DPAVBi), 2,5,8,11-tetra-tert-butylperylene (TBPe), and compound 4 below are examples of blue fluorescent dopants.

[0142]

[0143] The amount of the dopant can range from about 0.01 to about 50 parts by weight of the matrix, based on 100 parts by weight. Alternatively, the emitting layer can be composed of a light-emitting polymer. The EML can have a thickness of about 10 nm to about 100 nm, for example, about 20 nm to about 60 nm. When the thickness of the EML is within this range, the EML may exhibit excellent light emission without a significant increase in driving voltage.

[0144] Hole blocking layer (HBL)

[0145] When the EML contains phosphorescent dopants, a hole blocking layer (HBL) can be formed on the EML using vacuum deposition, spin coating, slot extrusion coating, printing, casting, LB deposition, etc., to prevent triplet excitons or holes from diffusing into the EML.

[0146] When the HBL is formed using vacuum deposition or spin coating, the conditions for deposition and coating can be similar to those for forming the HIL. However, the conditions for deposition and coating can vary depending on the compound used to form the HBL. Any compound commonly used to form HBLs can be used. Examples of compounds used to form the HBL include oxadiazole derivatives, triazole derivatives, and phenanthroline derivatives.

[0147] The HBL can have a thickness of about 5 nm to about 100 nm, for example, about 10 nm to about 30 nm. When the thickness of the HBL is within this range, the HBL may have excellent hole blocking performance without a significant increase in driving voltage.

[0148] Electron Transport Layer (ETL)

[0149] The OLED of the present invention may not contain an electron transport layer (ETL). However, the OLED of the present invention may optionally contain an electron transport layer (ETL).

[0150] The electron transport layer is disposed between the emitter layer and the organic semiconductor layer conforming to the present invention. The electron transport layer facilitates the transport of electrons from the organic semiconductor layer of the present invention to the emitter layer. Preferably, the electron transport layer is contact-sandwiched between the emitter layer and the organic semiconductor layer of the present invention. In another preferred embodiment, the electron transport layer is contact-sandwiched between a hole blocking layer and the organic semiconductor layer of the present invention.

[0151] Preferably, the electron transport layer is free of emitter dopants. In another preferred embodiment, the electron transport layer is free of metals, metal halides, metal salts, and / or lithium organometallic compounds.

[0152] According to various implementations, the OLED may include an electron transport layer or an electron transport layer stack, the latter including at least a first electron transport layer and at least a second electron transport layer.

[0153] According to various embodiments of the OLED of the present invention, the electron transport layer may comprise at least one matrix compound. Preferably, the at least one matrix compound is a substantially covalent matrix compound. More preferably, the matrix compound of the electron transport layer is an organic matrix compound.

[0154] It should be understood that "substantially covalent" means that the compound contains elements primarily bound together by covalent bonds. A substantially covalent matrix material consists of at least one substantially covalent compound. The substantially covalent material may contain low molecular weight compounds, preferably sufficiently stable to be processed by vacuum thermal evaporation (VTE). Alternatively, the substantially covalent material may contain polymeric compounds, preferably solvent-soluble compounds that can therefore be processed in solution form. It should be understood that substantially covalent materials in polymeric form can be crosslinked to form an infinite, irregular network; however, it is believed that these crosslinked substantially covalent matrix compounds in polymeric form still contain both skeletal atoms and peripheral atoms. The skeletal atoms of the substantially covalent compound are covalently bonded to at least two neighboring atoms.

[0155] Compounds containing cations and anions are considered substantially covalent if at least the cation or at least the anion contains at least nine covalently bonded atoms.

[0156] Preferred examples of substantially covalent matrix compounds are organomatrix compounds mainly composed of covalently bonded C, H, O, N, and S, which may optionally contain covalently bonded B, P, As, and Se. Organometallic compounds containing carbon-metal covalent bonds, metal complexes containing organic ligands, and metal salts of organic acids are other examples of organic compounds that can serve as organomatrix compounds.

[0157] In a more preferred embodiment, the organic matrix compound lacks metal atoms, and most of its skeletal atoms are selected from C, O, S, and N.

[0158] In a more preferred embodiment, the substantially covalent matrix compound comprises a conjugated system of at least 6, more preferably at least 10, or even more preferably at least 14 delocalized electrons.

[0159] An example of a delocalized electron conjugated system is a system of alternating π and σ bonds. Optionally, one or more diatomic structural units having π bonds between atoms can be replaced by atoms with at least one lone pair of electrons, typically divalent atoms selected from O, S, Se, and Te, or trivalent atoms selected from N, P, As, Sb, and Bi. Preferably, the delocalized electron conjugated system comprises at least one aromatic or heteroaromatic ring conforming to Hückel's rule. Furthermore, preferably, the substantially covalent matrix compound may comprise at least two aromatic or heteroaromatic rings connected or fused by covalent bonds.

[0160] Preferably, the electron transport layer comprises at least a second matrix compound. Suitable matrix compounds are described in EP15201418.9.

[0161] In a more preferred embodiment, the second organic matrix compound may be an organic matrix compound selected from: benzo[k]fluoranthene, pyrene, anthracene, fluorene, spiro(bisfluorene), phenanthrene, perylene, triptene, spiro[fluorene-9,9′-xanthenium], benzo[phenanthrene], xanthenium, benzo[furan], dibenzo[furan], dinaphtho[furan], acridine, benzo[c]acrididine, dibenzo[c,h]acrididine, dibenzo[a,j]acrididine, triazine, pyridine, pyrimidine, carbazole, phenyltriazole, benzimidazole, phenanthrene-rholine, oxadiazole, benzo[oxazole], oxazole, Quinazoline, benzo[h]quinazoline, pyrido[3,2-h]quinazoline, pyrimido[4,5-f]quinazoline, quinoline, benzoquinoline, pyrrolo[2,1-a]isoquinoline, benzofurano[2,3-d]pyridazine, thienopyrimidine, dithienothieno, benzothienopyrimidine, benzothienopyrimidine, phosphine oxide, phospharomonene, triarylborane, 2-(benzo[d]oxazol-2-yl)phenoxy metal complex, 2-(benzo[d]thiazo-2-yl)phenoxy metal complex or mixtures thereof.

[0162] According to a more preferred embodiment, an organic light-emitting diode (OLED) is provided, wherein the OLED includes at least one electron transport layer comprising a second organic matrix compound, wherein the organic semiconductor layer is sandwiched between the first cathode layer and the electron transport layer. The electron transport layer may comprise the second organic matrix compound having a dipole moment of approximately ≥0 Debye and approximately ≤2.5 Debye, preferably ≥0 Debye and <2.3 Debye, and more preferably ≥0 Debye and <2 Debye.

[0163] In another embodiment, an organic light-emitting diode (OLED) is provided, wherein the OLED comprises at least two electron transport layers, namely a first electron transport layer and a second electron transport layer. The first electron transport layer may comprise a second organic matrix compound, and the second electron transport layer may comprise a third organic matrix compound, wherein the second organic matrix compound of the first electron transport layer may be different from the third organic matrix compound of the second electron transport layer.

[0164] According to another embodiment, the dipole moment of the second organic matrix compound can be selected to be ≥0 Debye and ≤2.5 Debye, and the second organic matrix compound can also be described as a nonpolar matrix compound.

[0165] The dipole moment of a molecule containing N atoms It is given by the following formula:

[0166]

[0167]

[0168] Where q iand This represents the partial charge and position of atom i in the molecule. The dipole moment is determined using a semi-empirical molecular orbital method. The values ​​in Table 5 are calculated using the method described below. The partial charge and atomic position are obtained using the DFT functions of Becke and Perdew BP, performed as in the package TURBOMOLE V6.5, and the def-SV(P) basis set or the mixed function B3LYP and def2-TZVP basis set. If more than one conformation is feasible, the conformation with the lowest total energy is selected to determine the dipole moment.

[0169] For example, the second organic matrix compound may have a dipole moment between 0 and 2.5 Debye, and the first organic matrix compound may contain an inverted center I, a horizontal mirror plane, and more than one C. n Axis (n>1) and / or perpendicular to C n n C2s.

[0170] If the second organic matrix compound has a dipole moment between 0 and 2.5 Debye, the first organic matrix compound may contain anthracene group, pyrene group, perylene group, halophenyl group, benzo[k]fluoranthene group, fluorene group, xanthon group, dibenzo[c,h]acridin group, dibenzo[a,j]acridin group, benzo[c]acridin group, triarylborylalkyl group, dithienothiophene group, triazine group, or benzothienopyrimidine group.

[0171] If the second organic matrix compound has a dipole moment of about ≥0 Debye and about ≤2.5 Debye, then the second organic matrix compound may not contain imidazole, phenanthrene, phosphine oxide, oxazole, oxadiazole, triazole, pyrimidine, quinazoline, benzo[h]quinazoline, or pyrido[3,2-h]quinazoline groups.

[0172] In a preferred embodiment, the second organic matrix compound is selected from the following compounds or derivatives thereof, namely anthracene, pyrene, benzo[a,j]acridine, benzo[c]acridine, triarylborane compounds, 2-(benzo[d]oxazol-2-yl)phenoxy metal complex, 2-(benzo[d]thiazol-2-yl)phenoxy metal complex, triazine, benzothiophene-pyrimidine, dithiophene-thiophene, benzo[k]fluoranthene, perylene, or mixtures thereof.

[0173] In other preferred embodiments, the second organic matrix compound comprises a dibenzo[c,h]acridine compound of formula (2).

[0174]

[0175] and / or dibenzo[a,j]acridine compounds of formula (3)

[0176]

[0177] and / or benzo[c]acridine compounds of formula (4)

[0178]

[0179] Among them, Ar 3 Selected independently from: C6-C 20 arylene, preferably phenylene, biphenylene, or fluorene;

[0180] Ar 4 Independently selected from: unsubstituted or substituted C6-C 40 Aryl, preferably phenyl, naphthyl, anthraceneyl, pyrene, or phenanthryl;

[0181] And in Ar 4 In the case of substitution, the one or more substituents can be independently selected from: C1-C 12 Alkyl and C1-C 12 Heteroalkyl, wherein C1-C5 alkyl is preferred.

[0182] Suitable dibenzo[c,h]acridine compounds are disclosed in EP 2 395 571. Suitable dibenzo[a,j]acridine compounds are disclosed in EP 2 312 663. Suitable benzo[c]acridine compounds are disclosed in WO 2015 / 083948.

[0183] In other embodiments, preferably the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted dibenzo[c,h]acridine compounds, preferably 7-(naphth-2-yl)dibenzo[c,h]acridine, 7-(3-(pyrene-1-yl)phenyl)dibenzo[c,h]acridine, or 7-(3-(pyridin-4-yl)phenyl)dibenzo[c,h]acridine.

[0184] In other embodiments, preferably the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted dibenzo[a,j]acridine compounds, preferably 14-(3-(pyrene-1-yl)phenyl)dibenzo[a,j]acridine.

[0185] In other embodiments, preferably the second organic matrix compound comprises C6-C40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted benzo[c]acridine compounds, preferably 7-(3-(pyrene-1-yl)phenyl)benzo[c]acridine.

[0186] Perhaps more preferably, the second organic matrix compound comprises a triazine compound of formula (5).

[0187]

[0188] Among them, Ar 5 Independently selected from unsubstituted or substituted C6-C 20 Aryl or Ar 5.1 -Ar 5.2 ,

[0189] Among them, Ar 5.1 Selected from unsubstituted or substituted C6-C 20 Alpha-aryl, and

[0190] Ar 5,2 Selected from unsubstituted or substituted C6-C 20 Aryl or unsubstituted and substituted C5-C 20 Mixed aromatics;

[0191] Ar 6 Selected from unsubstituted or substituted C6-C 20 The arylene group is preferably phenylene, biphenylene, terphenylene, or fluorene.

[0192] Ar 7 The aryl group is independently selected from substituted or unsubstituted aryl groups, substituted or unsubstituted heteroaryl groups, wherein the aryl and heteroaryl groups have 6 to 40 ring-forming atoms, preferably phenyl, naphthyl, phenanthryl, fluorenyl, terphenyl, pyridyl, quinolinyl, pyrimidinyl, triazine, benzo[h]quinolinyl or benzo[4,5]thieno[3,2-d]pyrimidine;

[0193] x is selected from 1 or 2.

[0194] Among them, in Ar 5 In the case of substitution, the one or more substituents can be independently selected from C1-C2. 12 Alkyl and C1-C 12 Heteroalkyl groups, preferably C1-C5 alkyl groups;

[0195] And in Ar 7 In the case of substitution, the one or more substituents can be independently selected from C1-C2. 12 Alkyl and C1-C 12 Heteroalkyl, preferably C1-C5 alkyl, and selected from C6-C20 Aryl.

[0196] Suitable triazine compounds are disclosed in US 2011 / 284832, WO 2014 / 171541, WO 2015 / 008866, WO2015 / 105313, JP 2015-074649 A, JP 2015-126140 and KR 2015 / 0088712.

[0197] Furthermore, preferably, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted triazine compounds, preferably 3-[4-(4,6-di-2-naphthyl-1,3,5-triazin-2-yl)phenyl]quinolone, 2-[3-(6′-methyl[2,2′-bipyridin]-5-yl)-5-(9-phenanthyl)phenyl]-4,6-diphenyl-1,3,5-triazine, 2-(3-(phenanthro-9-yl)-5-(pyridin-2-yl)phenyl)-4,6-diphenyl-1,3,5-triazine, 2,4-diphenyl-6-(5″′-phenyl-[1,1′:3′,1″: 3″, 1″′: 3″′, 1″′′-pentaphenyl]-3-yl)-1,3,5-triazine, 2-([1,1′-biphenyl]-3-yl)-4-(3′-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)-6-phenyl-1,3,5-triazine and / or 2-(3′-(4,6-diphenyl-1,3,5-triazin-2-yl)-[1,1′-biphenyl]-3-yl)-4-phenylbenzo[4,5]thieno[3,2-d]pyrimidine.

[0198] Suitable 2-(benzo[d]oxazol-2-yl)phenoxy metal complexes or 2-(benzo[d]thiazolyl)phenoxy metal complexes are disclosed in WO 2010 / 020352.

[0199] In a preferred embodiment, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted benzothiophene-pyrimidine compounds, preferably 2-phenyl-4-(4′,5′,6′-triphenyl-[1,1′:2′,1′′:3″,1″′-tetraphenyl]-3″′-yl)benzo[4,5]thiophene-[3,2-d]pyrimidine. Suitable benzothiophene-pyrimidine compounds are disclosed in WO 2015 / 0105316.

[0200] In a preferred embodiment, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted benzo[k]fluoranthene compounds, preferably 7,12-diphenylbenzo[k]fluoranthene. Suitable benzo[k]fluoranthene compounds are disclosed in JP10189247 A2.

[0201] In a preferred embodiment, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted perylene compounds, preferably 3,9-bis([1,1'-biphenyl]-2-yl)perylene, 3,9-di(naphthyl-2-yl)perylene, or 3,10-di(naphthyl-2-yl)perylene. Suitable perylene compounds are disclosed in US2007202354.

[0202] In a preferred embodiment, the second organic matrix compound comprises a pyrene compound. Suitable pyrene compounds are disclosed in US20050025993.

[0203] In a preferred embodiment, the second organic matrix compound comprises a spirofluorene compound. Suitable spirofluorene compounds are disclosed in JP2005032686.

[0204] In a preferred embodiment, the second organic matrix compound comprises a xatonium compound. Suitable xatonium compounds are disclosed in US2003168970A and WO 2013149958.

[0205] In a preferred embodiment, the second organic matrix compound comprises a benzene compound. Suitable benzene compounds are disclosed in Adachi, C.; Tokito, S.; Tsutsui, T.; Saito, S., Japanese Journal of Applied Physics, Part 2: Letters (1988), 27(2), L269-L271.

[0206] In a preferred embodiment, the second organic matrix compound comprises a benzo[a]phenanthrene compound. Suitable benzo[a]phenanthrene compounds are disclosed in US20050025993.

[0207] In a preferred embodiment, the second organic matrix compound is selected from carbazole compounds. Suitable carbazole compounds are disclosed in US2015207079.

[0208] In a preferred embodiment, the second organic matrix compound is selected from dithienothiophene compounds. Suitable dithienothiophene compounds are disclosed in KR2011085784.

[0209] In a preferred embodiment, the second organic matrix compound comprises anthracene compound. Particularly preferred are anthracene compounds represented by the following formula 400:

[0210]

[0211] In Equation 400, Ar 111 and Ar 112 Each can be either substituted or unsubstituted C6-C independently. 60 Aryl; 113 To Ar 116 Each can be either substituted or unsubstituted C1-C independently. 10 Alkyl or substituted or unsubstituted C6-C 60 Aryl; and g, h, i, and j can each be an integer from 0 to 4 independently.

[0212] In some implementations, Ar in Formula 400 111 and Ar 112 Each of the following can be independently:

[0213] Phenylidene, naphthylene, phenanthrene, or pyrene; or

[0214] The phenylene, naphthylene, phenanthrene, fluorenyl or pyrene, each being substituted by at least one of phenyl, naphthyl or anthracene.

[0215] In Equation 400, g, h, i, and j can each be an integer, 0, 1, or 2, independently.

[0216] In Equation 400, Ar 113 To Ar 116 Each of the following can be independently:

[0217] C1-C 10 Alkyl group, which is substituted with at least one of phenyl, naphthyl or anthracene;

[0218] Phenyl, naphthyl, anthraceneyl, pyrene, phenanthryl, or fluoreneyl;

[0219] Phenyl, naphthyl, anthraceneyl, pyrene, phenanthrene, or fluorenyl, each atomized by a deuterium atom, a halogen atom, a hydroxyl group, a cyano group, a nitro group, an amino group, an amido group, a hydrazine group, a hydrazone group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphate group or a salt thereof, C1-C 60 Alkyl, C2-C 60 alkenyl, C2-C 60 alkynyl group, C1-C60 Substitution with at least one of alkoxy, phenyl, naphthyl, anthraceneyl, pyrene, phenanthryl, or fluorenyl; or

[0220]

[0221] However, the embodiments of the present invention are not limited thereto.

[0222] On the other hand, the electron transport layer may comprise a polar second organic matrix compound. Preferably, the second organic matrix compound has a dipole moment of about >2.5 Debye and <10 Debye, preferably >3 and <5 Debye, or even more preferably >2.5 and less than 4 Debye.

[0223] If an organic matrix compound has a dipole moment >2.5 and <10 Debye, the organic matrix compound can be described by one of the following symmetry groups: C1, C2, C3, C4, C5, C6, C7, C8, C9 ... n C nv Or C s .

[0224] When the organic matrix compound has a dipole moment of >2.5 and <10 Debye, the organic matrix compound may contain benzofuran, dibenzofuran, dinaphthofuran, pyridine, acridine, phenyltriazole, benzimidazole, phenanthrene, oxadiazole, benzoxazole, oxazole, quinazoline, benzoquinazoline, pyrido[3,2-h]quinazoline, pyrimido[4,5-f]quinazoline, quinoline, benzoquinoline, pyrrolo[2,1-a]isoquinoline, benzofuran[2,3-d]pyridazine, thienopyrimidine, phosphine oxide, phosphazene, or mixtures thereof.

[0225] Furthermore, preferably, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted phosphine oxide compounds, preferably (3-(dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide, 3-phenyl-3H-benzo[b]dinaphtho[2,1-d:1′,2′-f]phosphateheptane-3-oxide, phenyl di(pyrene-1-yl)phosphine oxide, bis(4-(anthracite-9-yl)phenyl)(phenyl)phosphine oxide, (3-(9,10-di(naphthocite-2-yl)anthracite-2-yl)phenyl)diphenylphosphine oxide, phenyl di(pyrene- 1-yl)phosphine oxide, diphenyl(5-(pyrene-1-yl)pyridin-2-yl)phosphine oxide, diphenyl(4′-(pyrene-1-yl)-[1,1′-biphenyl]-3-yl)phosphine oxide, diphenyl(4′-(pyrene-1-yl)-[1,1′-biphenyl]-3-yl)phosphine oxide, (3′-(dibenzo[c,h]acridin-7-yl)-[1,1′-biphenyl]-4-yl)diphenylphosphine oxide and / or phenylbis(3-(pyrene-1-yl)phenyl)phosphine oxide.

[0226] Diarylphosphine oxide compounds that can be used as second organic matrix compounds are disclosed in EP 2395571 A1, WO2013079217 A1, EP 13187905, EP13199361 and JP2002063989 A1. Dialkylphosphine oxide compounds are disclosed in EP15195877.4.

[0227] Furthermore, preferably, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted benzimidazole compounds, preferably 2-(4-(9,10-bis(naphthyl-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzimidazole, 1-(4-(10-([1,1′-biphenyl]-4-yl)anthracene-9-yl)phenyl)-2-ethyl-1H-benzimidazole and / or 1,3,5-tris(1-phenyl-1H-benzimidazole-2-yl)benzene.

[0228] Benzimidazole compounds that can be used as second organic matrix materials are disclosed in US 6878469 and WO2010134352.

[0229] In a preferred embodiment, the second organic matrix compound comprises a quinoline compound. Suitable quinoline compounds are disclosed in US 20090108746 and US 20090166670.

[0230] In a preferred embodiment, the second organic matrix compound comprises a benzoquinoline compound. Suitable benzoquinoline compounds are disclosed in JP 2004281390 and US 20120280613.

[0231] In a preferred embodiment, the second organic matrix compound comprises a pyrimidine compound. Suitable pyrimidine compounds are disclosed in JP2004031004.

[0232] In a preferred embodiment, the second organic matrix compound comprises an oxazole compound. Preferred oxazole compounds are disclosed in JP2003007467 and WO2014163173.

[0233] In a preferred embodiment, the second organic matrix compound comprises an oxadiazole compound. Preferred oxadiazole compounds are disclosed in US2015280160.

[0234] In a preferred embodiment, the second organic matrix compound comprises a benzoxazole compound. Preferred benzoxazole compounds are disclosed in Shirota and Kageyama, Chem. Rev. 2007, 107, 953-1010.

[0235] In a preferred embodiment, the second organic matrix compound comprises a triazole compound. Suitable triazole compounds are disclosed in US2015280160.

[0236] In a preferred embodiment, the second organic matrix compound comprises a pyrimido[4,5-f]quinazoline compound. Suitable pyrimido[4,5-f]quinazoline compounds are disclosed in EP2504871.

[0237] In a preferred embodiment, the second organic matrix compound may be selected from the following:

[0238] Compounds represented by Formula 2 and compounds represented by Formula 3:

[0239]

[0240] In formulas 2 and 3, R1 to R6 are each independently a hydrogen atom, a halogen atom, a hydroxyl group, a cyano group, or a substituted or unsubstituted C1-C group. 30 Alkyl, substituted or unsubstituted C1-C 30 Alkoxy, substituted or unsubstituted C1-C 30 Acyl, substituted or unsubstituted C2-C 30 alkenyl, substituted or unsubstituted C2-C 30 Alkyne, substituted or unsubstituted C6-C 30 Aryl or substituted or unsubstituted C3-C 30 Heteroaryl. At least two adjacent R1 to R6 groups are optionally bonded to each other to form a saturated or unsaturated ring. L1 is a bonded, substituted, or unsubstituted C1-C ring. 30 Alkylene, substituted or unsubstituted C6-C 30 aryl or substituted or unsubstituted C3-C 30 Hybrid aryl. Q1 to Q9 are each independently a hydrogen atom, substituted or unsubstituted C6-C. 30 Aryl or substituted or unsubstituted C3-C 30 The aryl group is a heteroaryl group, and "a" is an integer from 1 to 10.

[0241] For example, R1 to R6 can each be independently selected from: hydrogen atom, halogen atom, hydroxyl, cyano, methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy, butoxy, phenyl, naphthyl, anthracene, pyridyl, and pyrazinyl.

[0242] Specifically, in Formula 2 and / or 3, R1 to R4 can each be a hydrogen atom, and R5 can be selected from: halogen atom, hydroxyl, cyano, methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy, butoxy, phenyl, naphthyl, anthracene, pyridyl, and pyrazinyl. Furthermore, in Formula 3, R1 to R6 can each be a hydrogen atom.

[0243] For example, in Formula 2 and / or 3, Q1 to Q9 are each independently a hydrogen atom, phenyl, naphthyl, anthraceneyl, pyridyl, or pyrazinyl. Specifically, in Formula 2 and / or 3, Q1, Q3-Q6, Q8, and Q9 are hydrogen atoms, and Q2 and Q7 can each be independently selected from: phenyl, naphthyl, anthraceneyl, pyridyl, and pyrazinyl.

[0244] For example, in formula 2 and / or 3, L1 can be selected from: phenylene, naphthylene, anthraceneylene, pyridinylene, and pyrazinylene. Specifically, L1 can be phenylene or pyridinylene. For example, "a" can be 1, 2, or 3.

[0245] The second organic matrix compound may also be selected from compounds 5, 6, or 7 below:

[0246]

[0247] Preferably, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted phenanthroline compounds, preferably 2,4,7,9-tetraphenyl-1,10-phenanthroline, 4,7-diphenyl-2,9-di-p-tolyl-1,10-phenanthroline, 2,9-bis(biphenyl-4-yl)-4,7-diphenyl-1,10-phenanthroline and / or 3,8-bis(6-phenyl-2-pyridyl)-1,10-phenanthroline.

[0248] phenanthrene-rhein compounds that can be used as second organic matrix materials are disclosed in EP 1786050 A1 and CN102372708.

[0249] Other suitable second organometallic compounds that can be used are quinazoline compounds substituted with aryl or heteroaryl groups, preferably 9-phenyl-9′-(4-phenyl-2-quinazolinyl)-3,3′-bi-9H-carbazole. Furthermore, preferably, the first organometallic compound comprises C6-C... 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12Alkyl-substituted quinazoline compounds, preferably 9-phenyl-9′-(4-phenyl-2-quinazolinyl)-3,3′-bis-9H-carbazole. Quinazoline compounds that can be used as first organic matrix materials are disclosed in KR2012102374.

[0250] Furthermore, preferably, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted benzo[h]quinazoline compounds, preferably 4-(2-naphthyl)-2-[4-(3-quinolinyl)phenyl]-benzo[h]quinazoline. Benzo[h]quinazoline compounds that can be used as first organic matrix materials are disclosed in KR2014076522.

[0251] Furthermore, preferably, the second organic matrix compound comprises C6-C 40 Aryl, C5-C 40 heteroaryl and / or C1-C 12 Alkyl-substituted pyrido[3,2-h]quinazoline compounds, preferably 4-(naphth-1-yl)-2,7,9-triphenylpyrido[3,2-h]quinazoline. Pyrido[3,2-h]quinazoline compounds that can be used as first organic matrix materials are disclosed in EP1970371.

[0252] In other preferred embodiments, the second organic matrix compound is selected from acridine compounds. Suitable acridine compounds are disclosed in CN104650032.

[0253] In another embodiment, the electron transport layer may be in direct contact with the organic semiconductor layer of the present invention. If more than one electron transport layer exists, the organic semiconductor layer is contact-sandwiched between the first electron transport layer and the first cathode layer. If a second electron transport layer exists, it is contact-sandwiched between the emitter layer and the first electron transport layer.

[0254] According to various embodiments of the OLED of the present invention, the thickness of the electron transport layer can be in the range of about ≥0.5nm to about ≤95nm, preferably about ≥3nm to about ≤80nm, more preferably about ≥5nm to about ≤60nm, also preferably about ≥6nm to about ≤40nm, further preferably about ≥8nm to about ≤20nm, and more preferably about ≥10nm to about ≤18nm.

[0255] According to various embodiments of the OLED of the present invention, the thickness of the electron transport layer stack can be in the range of about ≥25nm to about ≤100nm, preferably about ≥30nm to about ≤80nm, more preferably about ≥35nm to about ≤60nm, and even more preferably about ≥36nm to about ≤40nm.

[0256] If an HBL is formed, the ETL can optionally be formed on the EML or on the HBL.

[0257] The ETL can have a stacked structure, preferably a stacked structure of two ETL layers, so that electron injection and transport can be balanced and holes can be efficiently blocked. In conventional OLEDs, because the amount of electrons and holes changes over time, the number of excitons generated in the emitter region may decrease after driving begins. As a result, carrier balance may not be maintained, thus reducing the lifetime of the OLED.

[0258] However, in the ETL, the first and second layers may have similar or identical energy levels, so that carrier balance can be maintained uniformly while controlling the electron transport rate.

[0259] The organic light-emitting device may include other electron transport layers, preferably a third and optional fourth electron transport layer, wherein the third and optional fourth electron transport layers are disposed between the charge-generating layer and the cathode. Preferably, the first and third electron transport layers are selected to be the same, and the second and fourth electron transport layers are selected to be the same.

[0260] The ETL can be formed on the EML by vacuum deposition, spin coating, slot extrusion coating, printing, casting, etc. When the ETL is formed by vacuum deposition or spin coating, the deposition and coating conditions can be similar to those used to form the HIL. However, the deposition and coating conditions can vary depending on the compound used to form the ETL.

[0261] In another embodiment, the ETL may contain an alkali metal organometallic compound and / or an alkali metal halide, preferably a lithium organometallic compound and / or lithium halide.

[0262] Depending on the specific circumstances, the lithium halide may be selected from LiF, LiCl, LiBr or LiJ, and is preferably LiF.

[0263] Depending on the specific circumstances, the alkali metal organometallic complex may be a lithium organometallic complex, and preferably the lithium organometallic complex may be selected from: lithium quinoline, lithium borate, lithium phenolate, lithium pyridinium or lithium Schiff base and lithium fluoride, preferably 2-(diphenylphospho)-phenol lithium, lithium tetrakis(1H-pyrazol-1-yl)borate, lithium quinoline of formula (III), lithium 2-(pyridin-2-yl)phenol lithium and LiF, and more preferably selected from: lithium 2-(diphenylphospho)-phenol lithium, lithium tetrakis(1H-pyrazol-1-yl)borate, lithium quinoline of formula (III) and lithium 2-(pyridin-2-yl)phenol lithium.

[0264] More preferably, the alkali metal organopolymer is a lithium organopolymer and / or the alkali metal halide is a lithium halide.

[0265] Suitable lithium-organic complexes are described in WO2016001283A1.

[0266] Charge generation layer

[0267] A charge generation layer (CGL) suitable for use in the OLED of the present invention is described in US 2012098012 A.

[0268] The charge generation layer typically consists of two layers. This charge generation layer can be a pn junction charge generation layer connecting an n-type charge generation layer and a p-type charge generation layer. The pn junction charge generation layer generates charges or separates them into holes and electrons; and injects these charges into each light-emitting layer. In other words, the n-type charge generation layer provides electrons to the first light-emitting layer adjacent to the anode, while the p-type charge generation layer provides holes to the second light-emitting layer adjacent to the cathode. This further improves the luminous efficiency of organic light-emitting devices with multiple light-emitting layers and simultaneously reduces the driving voltage.

[0269] The n-type charge generation layer can be composed of a metal or organic material doped with an n-type dopant. The metal can be selected from Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba, La, Ce, Sm, Eu, Tb, Dy, and Yb. Furthermore, conventional materials can be used for the n-type dopant and the matrix in the organic material doped with the n-type dopant. For example, the n-type dopant can be an alkali metal, an alkali metal compound, an alkaline earth metal, or an alkaline earth metal compound. More specifically, the n-type dopant can be selected from Cs, K, Rb, Mg, Na, Ca, Sr, Eu, and Yb. The matrix material can be selected from tris(8-hydroxyquinoline)aluminum, triazine, hydroxyquinoline derivatives, benzo[a]azole derivatives, and silicone derivatives.

[0270] The p-type charge generation layer can be composed of a metal or organic material doped with a p-type dopant. Here, the metal can be an alloy selected from Al, Cu, Fe, Pb, Zn, Au, Pt, W, In, Mo, Ni, and Ti, or a combination of two or more of these. Furthermore, conventional materials can be used for the p-type dopant and the matrix in the organic material doped with the p-type dopant. For example, the p-type dopant can be selected from tetrafluoro-7,7,8,8-tetracyano-p-quinone dimethane (F4-TCNQ), derivatives of tetracyano-p-quinone dimethane, axialene derivatives, iodine, FeCl3, FeF3, and SbCl5. Preferably, the p-type dopant is selected from axialene derivatives. The matrix may be selected from N,N′-di(naphthyl-1-yl)-N,N-diphenyl-benzidine (NPB), N,N′-diphenyl-N,N′-bis(3-methylphenyl)-1,1-biphenyl-4,4′-diamine (TPD), and N,N′,N′-tetranaphthyl-benzidine (TNB).

[0271] In another embodiment, the p-type charge-generating layer is arranged adjacent to the organic semiconductor layer. According to one embodiment, the p-type charge-generating layer may comprise a compound of formula 16:

[0272] in

[0273] Each A 1 To A 6 It can be hydrogen, halogen atom, nitrile (-CN), nitro (-NO2), sulfonyl (-SO2R), sulfoxide (-SOR), sulfonamide (-SO2NR), sulfonate (-SO3R), trifluoromethyl (-CF3), ester (-COOR), amide (-CONHR or -CONRR'), substituted or unsubstituted straight-chain or branched C1-C12 alkoxy, substituted or unsubstituted straight-chain or branched C1-C12 alkyl, substituted or unsubstituted straight-chain or branched C2-C12 alkenyl, substituted or unsubstituted aromatic or non-aromatic heterocycle, substituted or unsubstituted aryl, substituted or unsubstituted mono- or diarylamine, substituted or unsubstituted aralkylamine, etc.

[0274] Here, each of the above R and R' can be a substituted or unsubstituted C1-C 60 Alkyl, substituted or unsubstituted aryl, or substituted or unsubstituted 5- to 7-membered heterocycles, etc.

[0275] Particularly preferred are p-type charge-generating layers comprising compounds of formula (17).

[0276]

[0277] The p-type charge-generating layer is disposed on top of the n-type charge-generating layer. As the material for the p-type charge-generating layer, arylamine-based compounds can be used. One embodiment of the arylamine-based compound includes a compound of formula 18:

[0278] in

[0279] Ar1, Ar2, and Ar3 are each independently hydrogen or a hydrocarbon group. Here, at least one of Ar1, Ar2, and Ar3 may include aromatic hydrocarbon substituents, and each substituent may be the same or may be composed of different substituents. When Ar1, Ar2, and Ar3 are not aromatic hydrocarbons, they may be hydrogen, straight-chain, branched, or cyclic aliphatic hydrocarbons, or heterocyclic groups including N, O, S, or Se.

[0280] On the other hand, an organic light-emitting diode (OLED) of the present invention is provided, wherein the OLED further comprises a p-type charge-generating layer, wherein the organic semiconductor layer is disposed between the first emitting layer and the p-type charge-generating layer. Preferably, the p-type charge-generating layer comprises an axial ene dopant and a matrix, more preferably constituted therefrom.

[0281] In another embodiment, the p-type charge-generating layer is in direct contact with the organic semiconductor layer of the present invention. Preferably, the p-type charge-generating layer comprising an axial ene dopant and a matrix or thereof is in direct contact with the organic semiconductor layer.

[0282] On the other hand, the present invention provides an organic light-emitting diode that further includes a p-type charge-generating layer, wherein the p-type charge-generating layer is disposed between the organic semiconductor layer and the cathode. This arrangement allows for efficient electron injection into the emitting layer if the cathode is transparent to visible light emission.

[0283] Organic light-emitting diode (OLED)

[0284] According to another aspect of the invention, an organic light-emitting diode (OLED) is provided, comprising: a substrate, an anode, a hole injection layer, a hole transport layer, an optional electron blocking layer, an emission layer, an optional hole blocking layer, an optional electron transport layer, an organic semiconductor layer of the invention, an optional electron injection layer, and a cathode layer, wherein the layers are arranged in this order.

[0285] According to another aspect of the present invention, an organic light-emitting diode (OLED) is provided, comprising: a substrate, an anode, a first hole injection layer, a first hole transport layer, an optional first electron blocking layer, a first emission layer, an optional first hole blocking layer, an optional first electron transport layer, an optional organic semiconductor layer of the present invention, an n-type charge generating layer, a p-type charge generating layer, a second hole transport layer, an optional second electron blocking layer, a second emission layer, an optional second hole blocking layer, an optional second electron transport layer, an organic semiconductor layer, an optional electron injection layer, and a cathode layer, wherein the layers are arranged in this order.

[0286] According to various embodiments of the OLED of the present invention, the OLED may not include an electron transport layer.

[0287] According to various embodiments of the OLED of the present invention, the OLED may not contain an electron blocking layer.

[0288] According to various embodiments of the OLED of the present invention, the OLED may not include a hole blocking layer.

[0289] According to various embodiments of the OLED of the present invention, the OLED may not include a charge generation layer.

[0290] According to various embodiments of the OLED of the present invention, the OLED may not include a second emitting layer.

[0291] electronic devices

[0292] On the other hand, it relates to an electronic device that includes at least one organic light-emitting diode (OLED). Devices that include organic light-emitting diodes (OLEDs) are, for example, displays or lighting panels.

[0293] Other aspects and / or advantages of the invention will be set forth in part in the description which follows and will be apparent in part from the description, or may be learned by practice of the invention.

[0294] Manufacturing method

[0295] As mentioned above, the present invention relates to a method for manufacturing the organic light-emitting diode of the present invention, the method comprising the steps of sequentially forming an anode, at least one emission layer, at least one organic semiconductor layer and a cathode on a substrate, and forming the at least one organic semiconductor layer by co-depositing a substantially metallic rare earth metal dopant together with a first matrix compound comprising at least two phenanthroline groups, preferably two to four phenanthroline groups.

[0296] However, according to the present invention, the organic light-emitting diode is also manufactured by sequentially forming a cathode, at least one organic semiconductor layer, at least one emission layer and an anode on a substrate, wherein, similarly, the at least one organic semiconductor layer is formed by co-depositing a substantially metallic rare earth metal dopant together with a first matrix compound comprising at least two phenanthroline groups, preferably two to four phenanthroline groups.

[0297] In this regard, the term co-deposition specifically refers to depositing a rare earth metal dopant, which is essentially a metal, from a first evaporation source and preferably from a second evaporation source.

[0298] Surprisingly, rare earth metal dopants can be co-deposited with organic matrix compounds. This is extremely difficult to achieve for alkali metals, particularly Li, due to their very low doping concentrations compared to rare earth metal dopants. Therefore, alkali metals are typically deposited after the organic matrix compounds.

[0299] In another embodiment, the organic semiconductor layer is formed by co-depositing a substantially metallic rare-earth metal dopant together with a first matrix compound containing at least two phenanthroline groups in the same evaporation chamber.

[0300] According to another embodiment, the method includes a further step of depositing an electron transport layer on the emitter layer. In this case, the organic semiconductor layer is obviously deposited instead on the electron transport layer.

[0301] The deposition of the present invention can be achieved by deposition via vacuum thermal evaporation or deposition via solution processing. Preferably, the processing is selected from spin coating, printing, casting and / or slot extrusion coating.

[0302] Preferably, depositing the organic semiconductor layer includes vacuum thermal evaporation.

[0303] According to various embodiments of the invention, the method may further include forming an anode, a hole injection layer, a hole transport layer, an optional electron blocking layer, an emitter layer, an optional hole blocking layer, an optional electron transport layer, the organic semiconductor layer, an optional electron injection layer, and a cathode layer on a substrate, wherein the layers are arranged in this order; or the layers may be deposited in reverse order, starting with the cathode layer, and more preferably the organic semiconductor layer is deposited before the cathode layer is deposited.

[0304] When the organic semiconductor layer is deposited before the first cathode layer, particularly low operating voltage and / or high external quantum efficiency (EQE) can be achieved.

[0305] According to various embodiments of the present invention, the method may further include forming an anode, a first hole injection layer, a first hole transport layer, an optional first electron blocking layer, a first emitter layer, an optional first hole blocking layer, an optional first electron transport layer, an optional organic semiconductor layer of the present invention, a p-type charge generation layer, a second hole transport layer, an optional second electron blocking layer, a second emitter layer, an optional second hole blocking layer, an optional second electron transport layer, the organic semiconductor layer, and a cathode layer on a substrate, wherein the layers are arranged in this order; or the layers are deposited in reverse order, starting from the cathode layer, and more preferably the organic semiconductor layer is deposited before the cathode layer.

[0306] However, in one scenario, the layer is deposited upside down, starting from the cathode and sandwiched between the cathode and the anode.

[0307] For example, starting with the first cathode layer, the organic semiconductor layer, optional electron transport layer, optional hole blocking layer, emitter layer, optional electron blocking layer, hole transport layer, hole injection layer, and anode follow this exact order.

[0308] The anode and / or cathode may be deposited on a substrate. Preferably, the anode is deposited on a substrate.

[0309] According to another aspect of the present invention, a method for manufacturing an organic light-emitting diode (OLED) is provided, the method using:

[0310] - At least one sedimentary source, preferably two sedimentary sources, more preferably at least three sedimentary sources; and / or

[0311] - Deposition via vacuum thermal evaporation (VTE); and / or

[0312] - Deposition is performed by solution processing, preferably the processing being selected from: spin coating, printing, casting and / or slot extrusion coating. Attached Figure Description

[0313] These and / or other aspects and advantages of the invention will become apparent and more readily understood from the following description of exemplary embodiments, taken in conjunction with the accompanying drawings, in which:

[0314] Figure 1 This is a schematic cross-sectional view of an organic light-emitting diode (OLED) according to an exemplary embodiment of the present invention.

[0315] Figure 2 This is a schematic cross-sectional view of an OLED according to another exemplary embodiment of the present invention.

[0316] Figure 3This is a schematic cross-sectional view of an OLED according to another exemplary embodiment of the present invention.

[0317] Figure 4 This is a schematic cross-sectional view of a tandem OLED including a charge generation layer according to an exemplary embodiment of the present invention.

[0318] Figure 5 This is a schematic cross-sectional view of an OLED comprising a charge-generating layer in direct contact with the cathode, according to an exemplary embodiment of the present invention. Detailed Implementation

[0319] Exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings, examples of which are illustrated in the drawings, wherein similar designations in all the drawings refer to similar elements. Exemplary embodiments are described below with reference to the accompanying drawings in order to explain various aspects of the invention.

[0320] In this document, when a first element is referred to as being formed on or disposed on a second element, the first element may be directly disposed on the second element, or one or more other elements may be disposed therebetween. When a first element is referred to as being directly formed on or disposed on a second element, no other elements are disposed therebetween.

[0321] Figure 1 This is a schematic cross-sectional view of an organic light-emitting diode (OLED) 100 according to an exemplary embodiment of the present invention. The OLED 100 includes a substrate 110, an anode 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, and an emitter layer (EML) 150. An organic semiconductor layer 170 is deposited on the emitter layer (EML) 150. The organic semiconductor layer 170, comprising a substantially metallic rare-earth metal dopant and comprising at least two phenanthroline groups, preferably comprising a first matrix compound of Formula 1, or both, is directly formed on the EML 150. A cathode layer 190 is directly disposed on the organic semiconductor layer 170.

[0322] Figure 2 This is a schematic cross-sectional view of an OLED 100 according to another exemplary embodiment of the present invention. Figure 2 and Figure 1 The difference lies in Figure 2 The OLED 100 includes an electron transport layer 160.

[0323] refer to Figure 2The OLED 100 includes a substrate 110, an anode 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, and an emitter layer (EML) 150. An electron transport layer (ETL) 160 is disposed on the emitter layer (EML) 150. An organic semiconductor layer 170 is disposed on the electron transport layer (ETL) 160. The organic semiconductor layer 170, comprising a substantially metallic rare-earth metal dopant and containing at least two phenanthroline groups, preferably comprising a first matrix compound of formula 1, or both, is directly formed on the ETL 160. A cathode layer 190 is directly disposed on the organic semiconductor layer 170.

[0324] Figure 3 This is a schematic cross-sectional view of an OLED 100 according to another exemplary embodiment of the present invention. Figure 3 and Figure 2 The difference lies in Figure 3 The OLED 100 includes an electron blocking layer (EBL) 145 and a cathode 190 including a first cathode layer 191 and a second cathode layer 192.

[0325] refer to Figure 3 The OLED 100 includes a substrate 110, an anode 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, an electron blocking layer (EBL) 145, and an emitter layer (EML) 150. An electron transport layer (ETL) 160 is disposed on the emitter layer (EML) 150. An organic semiconductor layer 170 is disposed on the electron transport layer (ETL) 160. An organic semiconductor layer 170 comprising a substantially metallic rare-earth metal dopant and comprising at least two phenanthroline groups, preferably comprising a first matrix compound of formula 1, or both, is directly formed on the ETL 160. A cathode layer 190 includes a first cathode layer 191 and a second cathode layer 192. The first cathode layer 191 is a substantially metallic layer and is directly disposed on the organic semiconductor layer 170. The second cathode layer 192 is directly disposed on the first cathode layer 191.

[0326] Figure 4 This is a schematic cross-sectional view of a series OLED 100 according to another exemplary embodiment of the present invention. Figure 4 and Figure 2 The difference lies in Figure 4 OLEDs also include a charge generation layer and a second emission layer.

[0327] refer to Figure 4The OLED 100 includes a substrate 110, an anode 120, a first hole injection layer (HIL) 130, a first hole transport layer (HTL) 140, a first electron blocking layer (EBL) 145, a first emitter layer (EML) 150, a first hole blocking layer (HBL) 155, a first electron transport layer (ETL) 160, an n-type charge generation layer (n-type CGL) 185, a p-type charge generation layer (p-type GCL) 135, a second hole transport layer (HTL) 141, a second electron blocking layer (EBL) 146, a second emitter layer (EML) 151, a second hole blocking layer (EBL) 156, a second electron transport layer (ETL) 161, an organic semiconductor layer 170, a first cathode layer 191, and a second cathode layer 192. An organic semiconductor layer 170 comprising a substantially metallic rare-earth metal dopant and an organic semiconductor layer 170 comprising at least two phenanthroline groups, preferably comprising a first matrix compound of formula 1, or both, is directly disposed on the second electron transport layer 161, and a first cathode layer 191 is directly disposed on the organic semiconductor layer 170. A second cathode layer 192 is directly disposed on the first cathode layer 191. Optionally, an n-type charge generation layer (n-type CGL) 185 may be the organic semiconductor layer of the present invention.

[0328] Figure 5 This is a schematic cross-sectional view of an OLED 100 according to another exemplary embodiment of the present invention. Figure 5 and Figure 1 The difference lies in Figure 5 The OLED 100 also includes a p-type charge generation layer that is in direct contact with the cathode.

[0329] refer to Figure 5 OLED 100 includes a substrate 110, an anode 120, a hole injection layer (HIL) 130, a hole transport layer (HTL) 140, and an emitter layer (EML) 150. An organic semiconductor layer 170 is disposed on the emitter layer (EML) 150. The organic semiconductor layer 170, comprising a substantially metallic rare-earth metal dopant and comprising at least two phenanthroline groups, preferably comprising a first matrix compound of formula 1, or both, is directly formed on the EML 150. A p-type charge generation layer (p-type CGL) 135 is directly formed on the organic semiconductor layer 170 of the present invention. A cathode layer 190 is directly disposed on the p-type charge generation layer 135.

[0330] In the above description, the method of manufacturing OLED 100 of the present invention begins with a substrate 110 on which an anode 120 is formed. On the anode 120, a first hole injection layer 130, a first hole transport layer 140, an optional first electron blocking layer 145, a first emitter layer 150, an optional first hole blocking layer 155, an optional ETL 160, an n-type CGL 185, a p-type CGL 135, a second hole transport layer 141, an optional second electron blocking layer 146, a second emitter layer 151, an optional second hole blocking layer 156, an optional at least one second electron transport layer 161, an organic semiconductor layer 170, a first cathode layer 191, and an optional second cathode layer 192 are formed in the following order or reverse order.

[0331] Despite Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 Not shown, but a sealing layer can be further formed on the cathode 190 to seal the OLED 100. Furthermore, various other modifications can be applied to it.

[0332] Example

[0333] The first matrix compound containing at least two phenanthroline groups can be synthesized as described in JP2002352961.

[0334] Bottom-emitting device with an evaporated emitting layer

[0335] For bottom-emitting devices—Examples 1 to 3 and Comparative Examples 1 to 5—a 15Ω / cm ohmmeter of ITO with 90nm is used. 2 A glass substrate (available from Corning Co.) was cut to a size of 50 mm × 50 mm × 0.7 mm, ultrasonically cleaned with isopropanol for 5 minutes, ultrasonically cleaned with pure water for 5 minutes, and then cleaned again with UV ozone for 30 minutes to prepare the first electrode.

[0336] Then, 97 wt% of biphenyl-4-yl(9,9-diphenyl-9H-fluorene-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) and 3 wt% of 2,2′,2″-(cyclopropane-1,2,3-triethylene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) were vacuum-deposited onto the ITO electrode to form a 10 nm thick HIL. Then, biphenyl-4-yl(9,9-diphenyl-9H-fluorene-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine was vacuum-deposited onto the HIL to form a 130 nm thick HTL. 97 wt% of ABH113 (Sun Fine Chemicals) was used as the matrix and 3 wt% of NUBD370 (Sun Fine Chemicals) was used as the dopant. Chemicals) were deposited on the HTL to form an EML with a thickness of 20 nm that emits blue light.

[0337] Then, by configuring the matrix compound and metal dopant according to Examples 1 to 3 and Comparative Examples 1 to 5, the organic semiconductor layer is formed by directly depositing the matrix compound from a first deposition source and the rare earth metal dopant from a second deposition source onto the EML. The composition of the organic semiconductor layer can be seen in Table 1. In Examples 1 to 3, the matrix compound is a compound of Formula 1. The thickness of the organic semiconductor layer is 36 nm.

[0338] Then, through 10 -7 The cathode layer is formed by evaporating and / or sputtering cathode material under ultra-high vacuum and directly depositing the cathode layer on the organic semiconductor layer. The speed is from 0.1 to 10 nm / s (0.01 to...). A single thermal co-evaporation or sputtering process of one or more metals is performed at a rate of 100 nm to produce a uniform cathode with a thickness of 5 to 1000 nm. The cathode layer has a thickness of 100 nm. The composition of the cathode can be seen in Table 1. Al and Ag are evaporated, while ITO is sputtered onto the organic semiconductor layer using an RF magnetron sputtering process.

[0339] Bottom-emitting devices with solution-processed emitting layers

[0340] For bottom-emitting devices, it will have 15Ω / cm with 90nm ITO. 2 A glass substrate (available from Corning Co.) was cut to a size of 50 mm × 50 mm × 0.7 mm, ultrasonically cleaned with isopropanol for 5 minutes, ultrasonically cleaned with pure water for 5 minutes, and then cleaned again with UV ozone for 30 minutes to prepare the first electrode.

[0341] Then, PEDOT:PSS (Clevios PVP AI 4083) was directly spin-coated onto the top of the first electrode to form a 55 nm thick HIL. The HIL was baked on a hot plate at 150 °C for 5 min. A luminescent polymer, such as MEH-PPV, was then directly spin-coated onto the HIL to form a 40 nm thick EML. The EML was baked on a hot plate at 80 °C for 10 min. The device was then transferred to an evaporation chamber, and the following layers were deposited under high vacuum.

[0342] A first matrix compound containing at least two phenanthroline groups and a rare earth metal dopant are directly disposed on top of the EML to form an organic semiconductor layer with a thickness of 4 nm. A cathode layer is formed by directly disposing a 100 nm thick aluminum layer on top of the organic semiconductor layer.

[0343] Top light-emitting device

[0344] For the top-emitting devices—Examples 2 and 3—an anode is formed from 100 nm silver on a glass substrate. The glass substrate is fabricated using the same method described above for the bottom-emitting devices.

[0345] The HIL, HTL, EML, and organic semiconductor layers are configured as described above regarding the bottom light-emitting device.

[0346] Then, a cathode is deposited. In Example 2, a 13 nm Ag layer is formed in a high vacuum as described above regarding the bottom-emitting device. In Example 3, a 100 nm ITO layer is formed using a sputtering process.

[0347] A 60 nm biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-amine (CAS 1242056-42-3) was directly disposed on top of the cathode layer.

[0348] By encapsulating the OLED stack with a glass substrate, the device is protected from environmental damage. This creates a cavity containing a degassing agent material for further protection.

[0349] pn junction device as a model for OLEDs containing at least two emission layers

[0350] Manufacturing OLEDs containing at least two emitter layers is time-consuming and expensive. Therefore, the effectiveness of the organic semiconductor layer of the present invention was tested in a pn junction without an emitter layer. In this arrangement, the organic semiconductor layer acts as an n-type charge generation layer (CGL), positioned between the anode and cathode and in direct contact with the p-type CGL.

[0351] For pn junction devices—Examples 4 and 5 and Comparative Example 6—a 15Ω / cm junction with 90nm ITO will be used. 2 A glass substrate (available from Corning Co.) was cut to a size of 50 mm × 50 mm × 0.7 mm, ultrasonically cleaned with isopropanol for 5 minutes, ultrasonically cleaned with pure water for 5 minutes, and then cleaned again with UV ozone for 30 minutes to prepare the first electrode.

[0352] Then, 97 wt% of biphenyl-4-yl(9,9-diphenyl-9H-fluorene-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine (CAS 1242056-42-3) and 3 wt% of 2,2′,2″-(cyclopropane-1,2,3-trimethylene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile) were vacuum-deposited on the ITO electrode to form a 10 nm thick HIL. Then, 2,4-diphenyl-6-(3′-(triphenyl-2-yl)-[1,1′-biphenyl]-3-yl)-1,3,5-triazine (CAS 1638271-85-8) was vacuum-deposited on the HIL to form a 130 nm thick electron blocking layer (EBL).

[0353] Then, by configuring the matrix compound and metal dopant according to Examples 4 to 5 and Comparative Example 6, the organic semiconductor layer is formed by directly depositing the matrix compound from a first deposition source and the rare earth metal dopant from a second deposition source onto the EBL. The composition of the organic semiconductor layer can be seen in Table 2. In Examples 4 and 5, the matrix compound is a compound of Formula 1. The thickness of the organic semiconductor layer is 10 nm.

[0354] Then, the p-type CGL is formed by directly configuring the matrix and p-type dopant on the organic semiconductor layer. The composition of the p-type CGL can be seen in Table 2. In Comparative Example 6, a 10 nm layer of formula (17) was deposited. In Examples 4 and 5, 97 wt% of biphenyl-4-yl(9,9-diphenyl-9H-fluorene-2-yl)-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-amine, referred to as HT-1, and 3 wt% of 2,2′,2″-(cyclopropane-1,2,3-trimethylene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile), referred to as dopant 1, was vacuum deposited to form a p-type CGL with a thickness of 10 nm.

[0355] Then, a 30 nm layer of biphenyl-4-yl(9,9-diphenyl-9H-fluoren-2-yl)-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-amine is directly disposed on the p-type CGL to form a hole blocking layer (HBL).

[0356] Then, through 10 -7 The cathode layer is formed by evaporating aluminum under ultra-high vacuum and directly depositing the aluminum layer onto the HBL. The evaporation speed is from 0.1 to 10 nm / s (0.01 to...). A single thermal co-evaporation of one or more metals is performed at a rate of 100 nm to produce a uniform cathode with a thickness of 5 to 1000 nm. The cathode layer has a thickness of 100 nm.

[0357] The pn junction device is protected against environmental conditions by encapsulating it with a glass substrate. This creates a cavity containing a degassing agent for further protection.

[0358] To evaluate the performance of embodiments of the present invention compared to the prior art, current efficiency was measured under ambient conditions (20°C). Current and voltage measurements were performed using a Keithley 2400 source meter and recorded in V. For bottom-emitting devices, the efficiency was 10 mA / cm². 2 Below, for top-emitting devices, at 10mA / cm 2 Under these conditions, CIE coordinates and luminance in candles were measured using a calibrated CAS 140 spectrometer from Instrument Systems. The lifetime LT of the bottom-emitting device was measured under ambient conditions (20°C) and 10 mA / cm². 2 Measurements were taken using a Keithley 2400 source meter and recorded in hours. The lifetime LT of the top-emitting device under ambient conditions (20°C) and 8 mA / cm² was measured. 2 Measurements were taken below. The brightness of the device was measured using a calibrated photodiode. Lifetime LT was defined as the time until the device's brightness decreased to 97% of its initial value.

[0359] In bottom-emitting devices, emission is predominantly Lambertian and quantified using external quantum efficiency percentage (EQE). To determine the efficiency EQE in percentages, a calibrated photodiode at 10 mA / cm² was used. 2 The light output of the measuring device.

[0360] In the top-emitting device, the emission is forward-oriented, non-Lambertian, and highly dependent on the microcavity. Therefore, the efficiency (EQE) is higher compared to the bottom-emitting device. To determine the efficiency (EQE) in percentage terms, a calibrated photodiode at 10 mA / cm² was used. 2 The light output of the measuring device.

[0361] At 30mA / cm 2 The current density and voltage rise over time were measured at 85°C for more than 100 hours. The voltage rise was recorded in volts (V).

[0362] In pn junction devices, as described above for OLEDs, at 10 mA / cm 2 Determine the operating voltage.

[0363] Technical effects of the present invention

[0364] 1. Organic semiconductor layer in direct contact with the cathode

[0365] Table 1 shows the operating voltage, external quantum efficiency, and voltage rise over time for OLEDs containing a blue fluorescent emitting layer, a first matrix compound, metal dopants, and various cathodes.

[0366] In Comparative Examples 1 to 3, ETM-1 was used as the first matrix compound.

[0367]

[0368] ETM-1 contains a single phenanthrolin group. Various different metal dopants were tested, with operating voltages ranging from 4.4 to 6.7 V and external quantum efficiencies ranging from 1.9 to 3.6% EQE.

[0369] In Comparative Examples 4 and 5, MX1 was used as the first matrix compound. MX1 contains two phenanthroline groups. In Comparative Example 4, Li was used as the metal dopant. The operating voltage was 3.3 V and the external quantum efficiency was 5.2% EQE. The voltage increased by 0.18 V over time at 85 °C. In Comparative Example 5, Mg was used as the metal dopant. The operating voltage was 6 V and the external quantum efficiency was 4.3% EQE. To check the repeatability of the metal doping concentration across several manufacturing batches, the standard deviation of the true concentration of the metal dopant in the organic semiconductor layer and its effect on the operating voltage were determined. In Comparative Example 4, a variation in doping concentration of 0.06 mol% resulted in a variation in operating voltage of 0.09 V. This is a significant variation in operating voltage, which could potentially cause a large number of devices to fail to meet product specifications.

[0370] In Example 1, MX1 was used as the first matrix compound and Yb was used as the metal dopant. The operating voltage was very low, at 3.8 V, and the efficiency was further improved to 5.6% EQE. Compared to alkali metals and alkaline earth metals, Yb is significantly less hazardous. Furthermore, the voltage rise over time was significantly lower, at 0.04 V, compared to 0.18 V in Comparative Example 4. Another advantage of rare earth metal dopant is that higher doping concentrations can be used compared to Li. In Comparative Example 4, where the operating voltage is closest, 0.6 wt% Li was used. In Example 1, 11.1 wt% Yb was used. The standard deviation of the actual Yb concentration in the organic semiconductor layer was 0.04, and the standard deviation of the operating voltage was 0.02. In summary, the external quantum efficiency, voltage rise over time, and standard deviation of the operating voltage have been significantly improved.

[0371] In Example 2, MX1 was used as the first matrix compound and Yb was used as the metal dopant. The anode was formed from 100 nm Ag, and the cathode was formed from 13 nm Ag. Because the cathode was very thin, it was transparent to visible light emission. The efficiency was further improved to 7% EQE.

[0372] In Example 3, the same composition as in Example 2 was used in the organic semiconductor layer. The cathode was formed from 100 nm ITO, which is transparent to visible light emission. The efficiency remained very high at 6.6% EQE, and the operating voltage was low at 3.9 V.

[0373] In summary, significant improvements were achieved in external quantum efficiency, repeatability of metal doping concentration, and voltage stability over time at high temperatures. Furthermore, the operating voltage remains low, allowing for safe operation of rare-earth metal dopants while loading a VTE source, and reducing safety concerns during evaporation tool maintenance.

[0374] 2. Organic semiconductor layer in direct contact with p-type CGL

[0375] Table 2 shows the operating voltages of pn junction devices containing p-type CGLs and organic semiconductor layers containing a first matrix compound and metal dopants, as well as various cathodes.

[0376] In Comparative Example 6, Equation (17) was used as the p-type CGL. The organic semiconductor layer contained ETM-1 and a Yb metal dopant. ETM-1 contained a single phenanthroline group. The operating voltage was 7.2V.

[0377] In Example 4, Formula (17) is still used as the p-type CGL. The organic semiconductor layer contains MX1 and Yb metal dopants. MX1 contains two phenanthroline groups. The operating voltage is significantly improved to 4.9V.

[0378] In Example 5, HT-1 and dopant 1 were co-deposited to form a p-type CGL. The organic semiconductor layer contained MX1 and Yb metal dopants. The operating voltage was further improved to 4.8V.

[0379] Lower operating voltage provides the benefits of lower power consumption and longer battery life in mobile devices.

[0380] The features disclosed in the foregoing description, claims and drawings may be used separately or in any combination thereof as material for implementing the invention in a wide variety of forms.

[0381]

[0382]

Claims

1. An organic light-emitting diode (OLED) comprising an anode, a cathode, at least one emitting layer, and at least one organic semiconductor layer, wherein the at least one emitting layer and the at least one organic semiconductor layer are disposed between the anode and the cathode, and the at least one organic semiconductor layer comprises a zero-valent rare-earth metal dopant selected from Sm, Eu, and Yb and a first matrix compound, the first matrix compound being a compound of Formula 1: Formula 1 Where R 1 To R 7 Each is independently selected from: hydrogen, substituted or unsubstituted C6 to C6. 18 aryl, substituted or unsubstituted pyridyl, substituted or unsubstituted quinolinyl, substituted or unsubstituted C1 to C1 16 Alkyl, substituted or unsubstituted C1 to C 16 alkoxy, hydroxy or carboxyl, and / or the corresponding R group therein. 1 To R 7 Adjacent groups may bond to each other to form a ring; L 1 It is a single key or selected from: C6 to C 30 Alpha-aryl, C5 to C 30 Heteroaryl, C1 to C8 alkylene or C1 to C8 alkoxyalkylene; Ar 1 It is substituted or unsubstituted C6 to C 18 aryl or pyridyl; and n is an integer from 2 to 4, where each of the n phenanthroline groups (within parentheses) can be the same as or different from each other. in The organic light-emitting diode includes a first emission layer and a second emission layer, wherein the organic semiconductor layer is disposed between the first emission layer and the second emission layer; The organic light-emitting diode further includes a p-type charge generation layer, wherein the organic semiconductor layer is disposed between the first emission layer and the p-type charge generation layer; The p-type charge-generating layer comprises an axialene dopant and a matrix, or is composed of an axialene dopant and a matrix; and The organic semiconductor layer is in direct contact with the p-type charge generation layer.

2. The organic light-emitting diode according to claim 1, wherein the organic light-emitting diode comprises a first organic semiconductor layer and a second organic semiconductor layer, wherein the first organic semiconductor layer is disposed between the first emission layer and the second emission layer, and the second organic semiconductor layer is disposed between the cathode and the emission layer closest to the cathode.

3. The organic light-emitting diode of claim 1, further comprising an electron transport layer disposed between the at least one emitting layer and the at least one organic semiconductor layer.

4. The organic light-emitting diode according to claim 1, wherein the cathode is transparent to visible light emission.

5. The organic light-emitting diode according to claim 1, wherein the cathode comprises a first cathode layer and a second cathode layer.

6. The organic light-emitting diode according to claim 1, wherein n is 2 or 3.

7. The organic light emitting diode of claim 1, wherein L 1 is a single bond.

8. The organic light emitting diode of claim 1, wherein Ar 1 is a phenylene group.

9. The organic light-emitting diode according to claim 1, wherein R 1 To R 7 Independently selected from: hydrogen, C1 to C4 alkyl, C1 to C4 alkoxy, C6 to C 12 Aryl and C5 to C 12 Mixed aromatic compounds.

10. The organic light-emitting diode according to claim 1, wherein the axialene dopant is 2,2',2''-(cyclopropane-1,2,3-trimethylene)tris(2-(p-cyanotetrafluorophenyl)acetonitrile).

11. A method for manufacturing an organic light-emitting diode according to any one of claims 1-10, the method comprising the steps of: sequentially forming an anode, at least one emission layer, at least one organic semiconductor layer and a cathode on a substrate, and forming the at least one organic semiconductor layer by co-depositing a substantially metallic rare earth metal dopant together with a first matrix compound comprising at least two phenanthroline groups.

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