WO2024116031A1 - 発光デバイス - Google Patents

発光デバイス Download PDF

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Publication number
WO2024116031A1
WO2024116031A1 PCT/IB2023/061820 IB2023061820W WO2024116031A1 WO 2024116031 A1 WO2024116031 A1 WO 2024116031A1 IB 2023061820 W IB2023061820 W IB 2023061820W WO 2024116031 A1 WO2024116031 A1 WO 2024116031A1
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Prior art keywords
layer
light
abbreviation
skeleton
phenyl
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English (en)
French (fr)
Japanese (ja)
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瀬尾広美
大澤信晴
佐々木俊毅
渡部剛吉
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Semiconductor Energy Laboratory Co Ltd
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Semiconductor Energy Laboratory Co Ltd
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Priority to CN202380080609.1A priority Critical patent/CN120226483A/zh
Priority to KR1020257019095A priority patent/KR20250114508A/ko
Priority to JP2024560960A priority patent/JPWO2024116031A1/ja
Publication of WO2024116031A1 publication Critical patent/WO2024116031A1/ja
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    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/14—Carrier transporting layers
    • H10K50/16—Electron transporting layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/11—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/14—Carrier transporting layers
    • H10K50/15—Hole transporting layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/17—Carrier injection layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/17—Carrier injection layers
    • H10K50/171—Electron injection layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/10—OLEDs or polymer light-emitting diodes [PLED]
    • H10K50/18—Carrier blocking layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/80—Constructional details
    • H10K50/805—Electrodes
    • H10K50/81—Anodes
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K50/00—Organic light-emitting devices
    • H10K50/80—Constructional details
    • H10K50/805—Electrodes
    • H10K50/82—Cathodes
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H10K59/10—OLED displays
    • H10K59/12—Active-matrix OLED [AMOLED] displays
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/60—Organic compounds having low molecular weight
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K85/00—Organic materials used in the body or electrodes of devices covered by this subclass
    • H10K85/60—Organic compounds having low molecular weight
    • H10K85/649—Aromatic compounds comprising a hetero atom
    • H10K85/657—Polycyclic condensed heteroaromatic hydrocarbons
    • H10K85/6572—Polycyclic condensed heteroaromatic hydrocarbons comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K2101/00—Properties of the organic materials covered by group H10K85/00
    • H10K2101/30—Highest occupied molecular orbital [HOMO], lowest unoccupied molecular orbital [LUMO] or Fermi energy values

Definitions

  • One aspect of the present invention relates to a light-emitting device.
  • one embodiment of the present invention is not limited to the above technical field.
  • Examples of the technical field of one embodiment of the present invention include semiconductor devices, display devices, light-emitting devices, power storage devices, memory devices, electronic devices, lighting devices, input devices (e.g., touch sensors), input/output devices (e.g., touch panels), driving methods thereof, and manufacturing methods thereof.
  • Display devices have been developed for a variety of uses in recent years. For example, applications of large display devices include home television devices (also called televisions or television receivers), digital signage, and PIDs (Public Information Displays), while the development of smartphones and tablet terminals equipped with touch panels is underway for small display device applications.
  • home television devices also called televisions or television receivers
  • digital signage also called digital signage
  • PIDs Public Information Displays
  • Devices requiring high-resolution display devices include, for example, devices for virtual reality (VR), augmented reality (AR), substitution reality (SR), and mixed reality (MR), which are being actively developed.
  • VR virtual reality
  • AR augmented reality
  • SR substitution reality
  • MR mixed reality
  • Light-emitting devices also called light-emitting elements
  • display elements for use in display devices
  • Light-emitting devices also called EL devices or EL elements
  • EL devices that utilize the electroluminescence (EL) phenomenon, particularly organic EL devices that mainly use organic compounds, are suitable for display devices because they have features such as being easily made thin and lightweight, being capable of responding quickly to input signals, and being able to be driven using a constant-voltage DC power supply.
  • one aspect of the present invention aims to provide a novel light-emitting device.
  • another aspect of the present invention aims to provide a novel light-emitting device with good efficiency.
  • another aspect of the present invention aims to provide a novel light-emitting device with good reliability.
  • it is an object to provide a highly reliable display device.
  • it is an object to provide a highly precise display device.
  • it is an object to provide a highly precise and highly reliable display device.
  • the objective is to provide a new organic compound, a new light-emitting device, a new display device, a new display module, and a new electronic device.
  • One aspect of the present invention is a light-emitting device having a first electrode, a second electrode, and an EL layer, the EL layer being located between the first electrode and the second electrode, the EL layer having a light-emitting layer, an electron transport layer, and an electron injection layer, the electron transport layer being in contact with the electron injection layer, the electron injection layer having a function of blocking holes, and the electron transport layer being a layer having bipolar properties.
  • another aspect of the present invention is a light-emitting device having a first electrode, a second electrode, and an EL layer, the EL layer being located between the first electrode and the second electrode, the EL layer having a light-emitting layer, an electron transport layer, and an electron injection layer, the electron transport layer being in contact with the electron injection layer, the electron injection layer having a function of blocking holes, and the electron transport layer being a layer containing an organic compound having electron transport properties and an organic compound having hole transport properties.
  • another aspect of the present invention is a light-emitting device having a first electrode, a second electrode, and an EL layer, the EL layer being located between the first electrode and the second electrode, the EL layer having a light-emitting layer, an electron transport layer, and an electron injection layer, the electron transport layer being in contact with the electron injection layer, the electron injection layer containing an organic compound having a strong basicity of pKa 8 or more, and the electron transport layer containing an organic compound having electron transport properties and an organic compound having hole transport properties.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the EL layer further has an intermediate layer and a second light-emitting layer, the second light-emitting layer is located between the intermediate layer and the first electrode, and the intermediate layer has a layer containing an organic compound having a strong basicity of pKa 8 or more.
  • another aspect of the present invention is a light-emitting device in which, in the above configuration, the EL layer further comprises an intermediate layer, a second light-emitting layer, and a second electron transport layer, the second light-emitting layer is located between the intermediate layer and the first electrode, the second electron transport layer is located between the second light-emitting layer and the intermediate layer, and the intermediate layer has a layer containing an organic compound having a strong basicity of pKa 8 or more.
  • another aspect of the present invention is a light-emitting device in which, in the above configuration, the EL layer further comprises an intermediate layer, a second light-emitting layer, and a second electron transport layer, the second light-emitting layer is located between the intermediate layer and the first electrode, the second electron transport layer is located between the second light-emitting layer and the intermediate layer, the intermediate layer has a layer containing an organic compound having a strong basicity of pKa 8 or more, and the second electron transport layer has bipolar properties.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the intermediate layer has a P-type layer, and the P-type layer is located between the layer containing an organic compound having a strong basicity of pKa 8 or more and the light-emitting layer.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the HOMO level of the organic compound having hole transport properties is -5.9 eV or more and -5.0 eV or less.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the LUMO level of the organic compound having electron transport properties is -3.15 eV or more and -2.50 eV or less.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the organic compound having a strong basicity of pKa 8 or more has a guanidine skeleton.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the organic compound having a strong basicity of pKa 8 or more has a 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine skeleton.
  • another aspect of the present invention is a light-emitting device in which the organic compound having a strong basicity of pKa 8 or more does not have an electron-transporting skeleton.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the organic compound having a strong basicity of pKa 8 or more has a guanidine skeleton and does not have an electron-transporting skeleton.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the electron injection layer further contains a second organic compound having electron transport properties.
  • another aspect of the present invention is a light-emitting device having the above configuration, in which the organic compound having a strong basicity of pKa 8 or more does not have electron donating properties with respect to the organic compound having the second electron transport property.
  • another embodiment of the present invention is a light-emitting device having the above structure, wherein the electron injection layer has a spin density measured by electron spin resonance of 1 ⁇ 10 17 spins/cm 3 or less, preferably less than 1 ⁇ 10 16 spins/cm 3 .
  • a display module having the above-mentioned light-emitting device and at least one of a connector and an integrated circuit.
  • Or another aspect of the present invention is an electronic device having the above-mentioned light-emitting device and at least one of a housing, a battery, a camera, a speaker, and a microphone.
  • One aspect of the present invention can provide a novel light-emitting device.
  • another aspect of the present invention can provide a novel light-emitting device with good efficiency.
  • another aspect of the present invention can provide a novel light-emitting device with good reliability.
  • another embodiment of the present invention can provide a novel light-emitting device that can be used in a high-definition display device.
  • another embodiment of the present invention can provide a novel light-emitting device that can be used in a high-definition display device and has good efficiency.
  • another embodiment of the present invention can provide a novel light-emitting device that can be used in a high-definition display device and has good reliability.
  • a highly reliable display device can be provided.
  • a highly accurate display device can be provided.
  • a highly accurate and reliable display device can be provided.
  • 1A and 1B are band diagrams illustrating the driving mechanism of a light-emitting device of the present invention.
  • 2A and 2B are diagrams illustrating a light emitting device.
  • 3A and 3B are diagrams illustrating a light emitting device.
  • 4A and 4B are a top view and a cross-sectional view of a light emitting device.
  • 5A to 5E are cross-sectional views showing an example of a method for manufacturing a display device.
  • 6A to 6D are cross-sectional views showing an example of a method for manufacturing a display device.
  • 7A to 7D are cross-sectional views showing an example of a method for manufacturing a display device.
  • 8A to 8C are cross-sectional views showing an example of a method for manufacturing a display device.
  • FIG. 9A to 9C are cross-sectional views showing an example of a method for manufacturing a display device.
  • 10A to 10C are cross-sectional views showing an example of a method for manufacturing a display device.
  • 11A and 11B are perspective views showing a configuration example of a display module.
  • 12A and 12B are cross-sectional views showing a configuration example of a display device.
  • FIG. 13 is a perspective view showing a configuration example of a display device.
  • FIG. 14 is a cross-sectional view showing a configuration example of a display device.
  • FIG. 15 is a cross-sectional view showing a configuration example of a display device.
  • FIG. 16 is a cross-sectional view showing a configuration example of a display device.
  • 17A to 17D are diagrams showing an example of an electronic device.
  • 18A to 18F are diagrams showing an example of an electronic device.
  • 19A to 19G are diagrams showing an example of an electronic device.
  • FIG. 20 is a
  • a device fabricated using a metal mask or an FMM may be referred to as a device with an MM (metal mask) structure.
  • a device fabricated without using a metal mask or an FMM may be referred to as a device with an MML (metal maskless) structure.
  • Embodiment 1 As one of the methods for forming an organic semiconductor film into a predetermined shape, a vacuum deposition method using a metal mask (mask deposition) is widely used. However, in recent years, as density and definition are becoming higher, mask deposition is approaching its limit for further finer definition due to various reasons such as problems with alignment accuracy and problems with the placement distance to the substrate. On the other hand, it is expected that organic semiconductor devices with more dense patterns can be realized by processing the shape of the organic semiconductor film using a photolithography method. Furthermore, since photolithography is easier to produce large areas than mask deposition, research on processing organic semiconductor films using photolithography is being conducted.
  • alkali metals or alkaline earth metals, or compounds thereof are often used in the electron injection layer of light-emitting devices.
  • these Li compounds are highly reactive with water or oxygen, and deteriorate in an instant when exposed to the air, and no longer function as an electron injection layer.
  • the inventors have now discovered that a light-emitting device using a strongly basic organic compound in the electron injection layer instead of a Li compound or the like results in a light-emitting device with excellent characteristics.
  • Strongly basic organic compounds are less likely to deteriorate when exposed to the atmosphere, unlike alkali metals or alkaline earth metals or their compounds. Therefore, even if they are used in light-emitting devices that have undergone processing using a photolithography method that involves exposure to the atmosphere during the process, the light-emitting device is less likely to deteriorate due to deterioration of the strongly basic organic compound itself.
  • the driving voltage may be higher than that of light-emitting devices that use an alkali metal or alkaline earth metal, or a compound thereof, in the electron injection layer.
  • the inventors have discovered that in a light-emitting device using an organic compound with strong basicity in the electron injection layer, by making the electron transport layer a mixed layer of an organic compound with electron transport properties and an organic compound with hole transport properties, it is possible to fabricate a light-emitting device that is resistant to processing in the atmosphere, has good reliability, and has a low driving voltage.
  • the inventors have discovered that by forming the electron transport layer into a mixed layer of an organic compound having electron transport properties and an organic compound having hole transport properties, it is possible to suppress a significant increase in the driving voltage in a light-emitting device that uses a strongly basic organic compound in the electron injection layer instead of a Li compound.
  • the electron transport layer is a mixed layer of an organic compound having electron transport properties and an organic compound having hole transport properties, so that the electron transport layer smoothly transports holes, and the electron injection layer contains an organic compound having strong basicity with an acid dissociation constant pKa of 8 or more, so that the holes are blocked.
  • holes accumulate at the interface of the electron injection layer on the electron transport layer side, and electrons accumulate on the electron injection layer side of the cathode.
  • the accumulated charges form an electric double layer, generating an electric dipole and shifting the vacuum level, bringing the Fermi level of the cathode material closer to the LUMO level of the material in the electron injection layer that has electron transport properties, and electrons can be injected into the EL layer at a low voltage.
  • the position where holes accumulate is the interface on the electron transport layer side of the light-emitting layer, so the accumulation positions of holes accumulated at the interface on the electron transport layer side of the light-emitting layer and electrons accumulated on the electron injection layer side of the cathode are far apart.
  • a light-emitting device with a normal configuration has a weaker electric field due to the electric dipole, which leads to an increase in driving voltage.
  • the electron transport layer is preferably an electron transport layer having a relatively high hole transport property.
  • the highest occupied molecular orbital (HOMO) level of the organic compound having hole transport property contained in the electron transport layer is preferably -5.90 eV or more and -5.00 eV or less, preferably -5.80 eV or more and -5.00 eV or less, and more preferably -5.70 eV or more and -5.15 eV or less.
  • the lowest unoccupied molecular orbital (LUMO) level of the organic compound having electron transport property contained in the electron transport layer is preferably -3.15 eV or more and -2.50 eV or less, and preferably -3.00 eV or more and -2.70 eV or less.
  • the electron transport layer contains an organic compound having electron transport properties and an acid dissociation constant pKa of 4 or less.
  • an organic compound having electron transport properties has a skeleton having electron transport properties.
  • an organic compound having hole transport properties has a skeleton having hole transport properties.
  • the electron transporting skeleton is preferably a skeleton having a ⁇ -electron deficient heteroaromatic ring.
  • the skeleton having a ⁇ -electron deficient heteroaromatic ring is preferably a skeleton containing at least one of a polyazole skeleton, a pyridine skeleton, a diazine skeleton, and a triazine skeleton in the ring.
  • a pyrimidine skeleton, a pyrazine skeleton, a pyridazine skeleton, a pyridine skeleton, a triazine skeleton, a benzofuropyrimidine skeleton, a benzothienopyrimidine skeleton, a benzofuropyrazine skeleton, a benzothienopyrazine skeleton, and the like are preferred.
  • a pyrimidine skeleton, a pyrazine skeleton, a triazine skeleton, and a benzofuropyrimidine skeleton are preferred.
  • the hole transporting skeleton is preferably a skeleton having a ⁇ -electron rich heteroaromatic ring.
  • a ⁇ -electron rich heteroaromatic ring for example, a condensed aromatic ring containing at least one of a pyrrole skeleton, a furan skeleton, and a thiophene skeleton in the ring is preferred.
  • a carbazole skeleton, a dibenzothiophene skeleton, or a skeleton in which an aromatic ring or a heteroaromatic ring is further condensed to these is preferred.
  • the carbazole skeleton, the biscarbazole skeleton, and the indolocarbazole skeleton are preferred.
  • amine skeletons particularly triphenylamine skeletons.
  • organic compounds having electron transport properties include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-8), )phenyl]-9H-carbazole (abbreviation: CO11), 2,2',2"-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TP
  • organic compounds having a heteroaromatic ring with a diazine skeleton, organic compounds having a heteroaromatic ring with a pyridine skeleton, and organic compounds having a heteroaromatic ring with a triazine skeleton are preferable because of their good reliability.
  • organic compounds containing heteroaromatic rings with a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing heteroaromatic rings with a triazine skeleton have high electron transport properties and contribute to reducing the driving voltage.
  • organic compounds having hole transport properties include N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)- 4"-Phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-8-amine
  • the electron transport layer is preferably thin, but a thickness of 5 nm to 10 nm is preferable because it allows the production of a reliable light-emitting device.
  • the electron injection layer accumulates the holes injected from the anode, and is therefore either a layer that has the function of blocking holes or a layer that does not transport holes.
  • the electron injection layer is a layer that has electron transport properties, since it is necessary to transport and inject the electrons injected from the cathode to the electron transport layer.
  • an electron injection layer blocks holes can be determined by fabricating an electronic device that allows only holes to flow (hereinafter referred to as a hole-only device) and measuring the relationship between current density and voltage. For example, when the current density is significantly reduced when a target layer is sandwiched in a hole-only device such as that shown in Table 1, specifically, when a measurement is performed by sandwiching a target layer between the measurement devices shown in Table 1, and the current density is 0.01 mA/ cm2 or less at 10 V, the target layer can be regarded as a layer that blocks holes.
  • ITSO indium tin oxide containing silicon oxide
  • PCBBiF N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine
  • OCHD-003 stands for an electron acceptor material containing fluorine and has a molecular weight of 672.
  • the relationship between the current density and voltage when no layer 3 is formed can be compared with the relationship between the current density and voltage when a target layer is formed to a thickness of 10 nm on layer 3.
  • a layer that has a current density of 0.01 mA/cm2 or less at 10 V can be considered to be a layer that blocks holes.
  • Figure 20 shows an example of measurement using such a device.
  • layer 3 of the hole-only device for the measurement contains N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: ⁇ NCCP), 1-(2',7'-di-tert-butyl-9,9'-spirobi[9H-fluoren]-2-yl)-1,3,4,6, These are the results for devices on which films of 7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine (abbreviation: 2',7'tBu-2hppSF), 2,2'-(1,3-phenylene)bis(9-phenyl-1,
  • the layers formed with PCBBiF, ⁇ NCCP, mPPhen2P, mPPhen2P:PCBBiF (1:1, weight ratio), and mPPhen2P: ⁇ NCCP (1:1, weight ratio) are layers that do not block holes, while the layer formed with mPPhen2P:2',7'tBu-hppSF (1:1, weight ratio) and the layer formed with 2',7'tBu-2hppSF are layers that block holes.
  • the layer to be measured is a mixed layer of material A and material B
  • a device (device A) in which the layer is provided as the measurement target layer of the hole-only device, and a device (device B) in which either material A or material B, whichever has a deeper HOMO level, is provided as a single layer as the measurement target layer are fabricated.
  • the layer can be said to be a hole-blocking layer.
  • the electron injection layer preferably contains an organic compound having a strong basicity with an acid dissociation constant pKa of 8 or more.
  • an organic compound having a strong basicity with a pKa of 8 or more By containing an organic compound having a strong basicity with a pKa of 8 or more, the electron injection layer can block holes and accumulate holes in the electron transport layer.
  • 2hppSF is a substance having a strong basicity with an acid dissociation constant of 13.95.
  • the above-mentioned substance having a strong basicity of pKa 8 or more does not have an electron transporting skeleton. This is to suppress recombination between the electrons injected into the electron injection layer and the holes trapped in the material with a large acid dissociation constant pKa, and to allow efficient injection into the electron transport layer.
  • the substance having an acid dissociation constant pKa of 8 or more is preferably an organic compound having a basic skeleton, and the acid dissociation constant pKa of the basic skeleton is preferably 10 or more. More preferably, the substance has an acid dissociation constant pKa of 12 or more.
  • the acid dissociation constant pKa of a basic skeleton can be the value of an organic compound in which part of the skeleton is replaced with hydrogen.
  • the acid dissociation constant pKa of a basic skeleton can be used as an indicator of the acidity of an organic compound having a basic skeleton.
  • the acid dissociation constant pKa of the basic skeleton with the highest acid dissociation constant pKa can be used as an indicator of the acidity of the organic compound. It is preferable to use a value measured using water as a solvent for the acid dissociation constant pKa.
  • the acid dissociation constant pKa of an organic compound may be calculated as follows:
  • the initial molecular structure of each molecule that serves as the calculation model is set to the most stable structure (singlet ground state) obtained from first-principles calculations.
  • pKa calculations For pKa calculations, one or more atoms of each molecule are designated as basic sites, and Macro Model is used to search for stable structures in water for protonated molecules. A conformational search is performed using the OPLS2005 force field, and the lowest energy conformer is used. Using Jaguar's pKa calculation module, the structure is optimized with B3LYP/6-31G*, and then a single-point calculation is performed with cc-pVTZ(+), and the pKa value is calculated using an empirical correction for the functional group. For molecules with one or more atoms designated as basic sites, the largest value among the results obtained is used as the pKa value.
  • organic compounds with a high acid dissociation constant pKa organic compounds having a pyrrolidine skeleton, a piperidine skeleton, or a hexahydropyrimidopyrimidine skeleton are preferred. Also, organic compounds having a guanidine skeleton are preferred. Specifically, examples include organic compounds having basic skeletons represented by the following structural formulas (120) to (123).
  • the organic compound having an acid dissociation constant pKa of 8 or more is preferably an organic compound having a bicyclo ring structure having two or more nitrogen atoms in the ring and a heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms in the ring or an aromatic hydrocarbon ring having 6 to 30 carbon atoms in the ring, more preferably an organic compound having a 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine skeleton and a heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms in the ring or an aromatic hydrocarbon ring having 6 to 30 carbon atoms in the ring.
  • an organic compound having a bicyclo ring structure having two or more nitrogen atoms in the ring and a heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms in the ring is more preferably an organic compound having a 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine skeleton and a heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms in the ring, is more preferably an organic compound having a 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine skeleton and a heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms in the ring.
  • organic compound be represented by the following general formula (G1):
  • X is a group represented by the following general formula (G1-1)
  • Y is a group represented by the following general formula (G1-2).
  • R1 and R2 each independently represent hydrogen or deuterium
  • h represents an integer of 1 to 6
  • Ar represents a substituted or unsubstituted heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms constituting the ring, or an aromatic hydrocarbon ring having 6 to 30 carbon atoms constituting the ring.
  • Ar is preferably a substituted or unsubstituted heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms constituting the ring.
  • R3 to R6 each independently represent hydrogen or deuterium, m represents an integer of 0 to 4, n represents an integer of 1 to 5, and mn+1 or greater. When m or n is 2 or greater, the multiple R3 to R6 may be the same or different.
  • the organic compound represented by the above general formula (G1) is preferably any one of the following general formulas (G2-1) to (G2-6).
  • R 11 to R 26 each independently represent hydrogen or deuterium
  • h represents an integer of 1 to 6
  • Ar is a substituted or unsubstituted heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms constituting a ring, or a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 carbon atoms constituting a ring.
  • Ar is preferably a substituted or unsubstituted heteroaromatic hydrocarbon ring having 2 to 30 carbon atoms constituting a ring.
  • examples of the substituted or unsubstituted heteroaromatic hydrocarbon ring represented by Ar having 2 to 30 carbon atoms constituting the ring or the aromatic hydrocarbon ring having 6 to 30 carbon atoms constituting the ring include specifically a pyridine ring, a bipyridine ring, a pyrimidine ring, a bipyrimidine ring, a pyrazine ring, a bipyrazine ring, a triazine ring, a quinoline ring, an isoquinoline ring, a benzoquinoline ring, a phenanthroline ring, a quinoxaline ring, a benzoquinoxaline ring, a dibenzoquinoxaline ring, an azofluorene ring, a diazofluorene ring, a carbazole ring, a benzocarbazole ring, a di ...
  • the ring examples include a benzofuran ring, a benzonaphthofuran ring, a dinaphthofuran ring, a dibenzothiophene ring, a benzonaphthothiophene ring, a dinaphthothiophene ring, a benzofuropyridine ring, a benzofuropyrimidine ring, a benzothiopyrimidine ring, a naphthofuropyridine ring, a naphthofuropyrimidine ring, a naphthothiopyridine ring, a naphthothiopyrimidine ring, an acridine ring, a xanthene ring, a phenothiazine ring, a phenoxazine ring, a phenazine ring, a triazole ring, an oxazole ring, an oxadiazole ring
  • examples of the heteroaromatic hydrocarbon ring having 6 to 30 carbon atoms constituting the substituted or unsubstituted ring represented by Ar include a benzene ring, a naphthalene ring, a fluorene ring, a dimethylfluorene ring, a diphenylfluorene ring, a spirofluorene ring, an anthracene ring, a phenanthrene ring, a triphenylene ring, a pyrene ring, a tetracene ring, a chrysene ring, and a benzo[a]anthracene ring.
  • any one of the following structural formulas (Ar-1) to (Ar-27) is preferable.
  • the above Ar contains nitrogen as an atom constituting a ring, and that Ar is bonded to the skeleton in parentheses in the general formula (G1) via a bond to the nitrogen or a carbon adjacent to the nitrogen.
  • organic compounds represented by the above general formula (G1) and general formulas (G2-1) to (G2-6) include organic compounds represented by the following structural formulas (101) to (117), such as 1,1'-(9,9'-spirobi[9H-fluorene]-2,7-diyl)bis(1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine) (abbreviation: 2,7hpp2SF) (structural formula 108) and 1-(9,9'-spirobi[9H-fluorene]-2-yl)-1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine (abbreviation: 2hppSF) (structural formula 109).
  • structural formulas (101) to (117) such as 1,1'-(9,9'-spirobi[9H-fluorene]-2,7-diyl)bis(1,3,4,6,7,8-hexahydro
  • organic compounds having a spirofluorene skeleton such as (106) to (109), or organic compounds having one hexahydropyrimidopyrimidine skeleton such as (102), (104), (105), (109), (110), and (115) are preferred, and the organic compound represented by (109) is particularly preferred.
  • organic compounds are less likely to cause metal contamination in the manufacturing line, unlike alkali metals or alkaline earth metals or their compounds, and are easy to vapor-deposit, making them suitable for use in light-emitting devices fabricated using photolithography processes. Of course, they are also suitable for light-emitting devices fabricated using processes that do not use photolithography.
  • the substance having a strong basicity of pKa 8 or more does not have an electron transporting skeleton from the viewpoint of suppressing recombination of the injected electron and the blocked hole on the substance having a strong basicity of pKa 8 or more.
  • the substance having a strong basicity of pKa 8 or more include 1-(9,9'-spirobi[9H-fluorene]-2-yl)-1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine (abbreviation: 2hppSF), 2,9-bis(1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidin-1-yl)-1,1
  • Organic compounds such as 0-phenanthroline (abbreviation: 2,9hpp2Phen), 4,7-di-1-pyrrolidinyl-1,10-phenanthroline (abbreviation: Pyrrd-Phen) or 8,8'-pyridine-2,6-diyl-bis(5,6,7,8-tetrahydroimidazo[1,2-a]pyrimidine) (abbreviation: 2,6tip2Py) can be used.
  • the electron injection layer preferably contains a material having electron transport properties in addition to a substance having a strong basicity of pKa 8 or more.
  • materials having electron transport properties include metal complexes such as bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq 2 ), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), and organic compounds having a ⁇ -electron-deficient heteroaromatic ring.
  • organic compounds having a ⁇ -electron-deficient heteroaromatic ring skeleton include organic compounds containing a heteroaromatic ring having a polyazole skeleton, organic compounds containing a heteroaromatic ring having a pyridine skeleton, organic compounds containing a heteroaromatic ring having a diazine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton.
  • organic compounds containing a heteroaromatic ring having a diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), organic compounds containing a heteroaromatic ring having a pyridine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton are preferred because of their good reliability.
  • organic compounds containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing a heteroaromatic ring having a triazine skeleton have high electron transport properties and contribute to reducing the driving voltage.
  • benzofuropyrimidine skeleton, benzothienopyrimidine skeleton, benzofuropyrazine skeleton, and benzothienopyrazine skeleton are preferred because of their good reliability.
  • organic compound having a ⁇ -electron-deficient heteroaromatic ring skeleton the materials listed as the organic compound having electron transport properties in the first electron transport layer can be used.
  • organic compounds containing a heteroaromatic ring having a diazine skeleton, organic compounds containing a heteroaromatic ring having a pyridine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton are preferable because they have good reliability.
  • organic compounds containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing a heteroaromatic ring having a triazine skeleton have high electron transport properties and contribute to reducing the driving voltage.
  • organic compounds having a phenanthroline skeleton such as mTpPPhen, PnNPhen, and mPPhen2P are preferable, and organic compounds having a phenanthroline dimer structure such as mPPhen2P are more preferable because they have excellent stability.
  • materials having a pyridine skeleton or a phenanthroline skeleton have high pKa, and therefore have high hole blocking properties, and are particularly preferable as electron transport materials used in the electron injection layer in the light-emitting device of one embodiment of the present invention.
  • the LUMO level of the material having electron transport properties in the electron injection layer is -3.00 eV or more and -2.00 eV or less, since this lowers the barrier for electron injection into the light-emitting layer.
  • the thickness of the electron injection layer is thin, but if it is too thick, the driving voltage increases, and if it is too thin, the characteristics, especially the reliability, deteriorate, so the thickness is preferably 2 nm to 13 nm, more preferably 5 nm to 10 nm.
  • the strongly basic substance in the electron injection layer does not have electron donating properties.
  • the strongly basic substance does not have electron donating properties to the material having electron transport properties.
  • the strongly basic substance has electron donating properties, it reacts more easily with atmospheric components such as water or oxygen, resulting in poor stability.
  • the hole transport properties of the electron injection layer can be significantly reduced, so that even if the strongly basic substance does not have electron donating properties, it can function as an intermediate layer of a tandem structure. Therefore, an intermediate layer and a tandem light-emitting device that are stable to atmospheric components such as water or oxygen can be manufactured.
  • the electron injection layer has a small signal observed by electron spin resonance (ESR), or no signal is observed.
  • ESR electron spin resonance
  • the spin density due to a signal observed near g-value 2.00 is preferably 1 ⁇ 10 17 spins/cm 3 or less, more preferably less than 1 ⁇ 10 16 spins/cm 3 .
  • a light-emitting device having the above-described structure can be a highly reliable light-emitting device with high current efficiency and suppressed increase in driving voltage.
  • the light-emitting device of one embodiment of the present invention is particularly suitable for light-emitting devices that have undergone a photolithography process, but light-emitting devices manufactured without undergoing a photolithography process also have high stability against the atmosphere, which improves yields and contributes to cost reduction by eliminating the need for stricter atmospheric control during the manufacturing process.
  • FIG. 2 is a schematic diagram of a light-emitting device according to one embodiment of the present invention.
  • the light-emitting device has a first electrode 101 provided on an insulator 100, and an EL layer 103 between the first electrode 101 and a second electrode 102.
  • the EL layer 103 has at least a light-emitting layer 113, an electron transport layer 114, and an electron injection layer 115.
  • the light-emitting layer 113 is a layer containing a light-emitting substance, and emits light when a voltage is applied between the first electrode 101 and the second electrode 102.
  • the EL layer 103 preferably has functional layers such as a hole injection layer 111 and a hole transport layer 112 as shown in FIG. 2A.
  • the EL layer 103 may also include functional layers other than those mentioned above, such as a hole blocking layer, an exciton blocking layer, and an intermediate layer. Conversely, any of the layers mentioned above may not be provided.
  • the electron injection layer 115 is a layer containing an organic compound having strong basicity as described in embodiment 1.
  • the electron injection layer 115 may further contain an organic compound having electron transport properties.
  • the electron transport layer 114 is a layer that contains an organic compound that has electron transport properties and an organic compound that has hole transport properties.
  • the first electrode 101 is an electrode including an anode
  • the second electrode 102 is an electrode including a cathode.
  • the second electrode 102 may be formed on the insulator 100 side, so-called a reverse-stacked configuration.
  • the light-emitting device has a stacked structure in the order of the second electrode 102, the electron injection layer 115, the electron transport layer 114, the light-emitting layer 113, (the hole transport layer 112, the hole injection layer 111, and) the first electrode 101 from the insulator 100 side.
  • the relatively stable hole injection layer 111 becomes the surface, so that the light-emitting device can be made more reliable.
  • the first electrode 101 and the second electrode 102 may be formed as a single layer structure or a laminated structure.
  • the layer in contact with the EL layer 103 functions as an anode or a cathode.
  • the electrode has a laminated structure, there are no restrictions on the work function of layers other than the layer in contact with the EL layer 103, and materials may be selected according to the required characteristics such as resistance value, ease of processing, reflectance, translucency, and stability.
  • the anode is preferably formed using a metal, alloy, conductive compound, or mixture thereof with a large work function (specifically, 4.0 eV or more).
  • a metal, alloy, conductive compound, or mixture thereof with a large work function specifically, 4.0 eV or more.
  • Specific examples include indium oxide-tin oxide (ITO), indium oxide-tin oxide containing silicon or silicon oxide (ITSO), indium oxide-zinc oxide, and indium oxide containing tungsten oxide and zinc oxide (IWZO).
  • ITO indium oxide-tin oxide
  • ITSO indium oxide-tin oxide containing silicon or silicon oxide
  • IWZO indium oxide containing tungsten oxide and zinc oxide
  • These conductive metal oxide films are usually formed by sputtering, but may also be formed by applying a sol-gel method.
  • a method for forming indium oxide-zinc oxide a method of forming the film by sputtering using a target in which 1 to 20 wt % zinc oxide
  • indium oxide containing tungsten oxide and zinc oxide can be formed by sputtering using a target containing 0.5 to 5 wt% tungsten oxide and 0.1 to 1 wt% zinc oxide relative to indium oxide.
  • Other materials used for the anode include, for example, gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti), aluminum (Al), or nitrides of metal materials (for example, titanium nitride). A layer of these laminated materials may also be used as the anode.
  • a film laminated in the order of Al, Ti, and ITSO on Ti is preferable because it has a good reflectance, is highly efficient, and can be highly fine-tuned to several thousand ppi.
  • graphene can also be used as a material used for the anode.
  • a composite material capable of forming the hole injection layer 111 described later as a layer in contact with the anode typically the hole injection layer
  • the hole injection layer 111 is provided in contact with the anode and has a function of facilitating injection of holes into the EL layer 103.
  • the hole injection layer 111 can be formed of a phthalocyanine-based compound or complex compound such as phthalocyanine (abbreviation: H 2 Pc) or copper phthalocyanine (abbreviation: CuPc), an aromatic amine compound such as 4,4′-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB) or 4,4′-bis(N- ⁇ 4-[N′-(3-methylphenyl)-N′-phenylamino]phenyl ⁇ -N-phenylamino)biphenyl (abbreviation: DNTPD), or a polymer such as poly(3,4-ethylenedioxythiophene)/(polystyrenesulfonic acid) (abbreviation: PEDOT/PSS
  • the hole injection layer 111 may be formed of a substance having electron acceptor properties.
  • an organic compound having an electron-withdrawing group such as a halogen group or a cyano group
  • examples thereof include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyren-2-ylidene)malononitrile, and the like.
  • compounds having an electron-withdrawing group bonded to a condensed aromatic ring having a plurality of heteroatoms such as HAT-CN are thermally stable and preferred.
  • Also, radialene derivatives having an electron-withdrawing group (especially halogen groups such as fluoro groups, cyano groups, etc.) [3] are preferred because they have a very high electron-accepting property, and specifically, ⁇ , ⁇ ', ⁇ ''-1,2,3-cyclopropane triylidene tris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], ⁇ , ⁇ ', ⁇ ''-1,2,3-cyclopropane triylidene tris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], ⁇ , ⁇ ', ⁇ ''-1,2,3-cyclopropane triylidene tris[2,3,4,5,6-penta
  • the hole injection layer 111 is formed from a composite material containing the above-mentioned material having acceptor properties and an organic compound having hole transport properties.
  • organic compound having hole transport properties used in the composite material various organic compounds such as aromatic amine compounds, heteroaromatic compounds, aromatic hydrocarbons, and polymeric compounds (oligomers, dendrimers, polymers, etc.) can be used.
  • organic compound having hole transport properties used in the composite material it is preferable that it is an organic compound having a hole mobility of 1 ⁇ 10 ⁇ 6 cm 2 /Vs or more.
  • the organic compound having hole transport properties used in the composite material is a compound having a condensed aromatic hydrocarbon ring or a ⁇ -electron-rich heteroaromatic ring.
  • condensed aromatic hydrocarbon ring an anthracene ring, a naphthalene ring, etc.
  • the ⁇ -electron-rich heteroaromatic ring it is preferable that it is a condensed aromatic ring containing at least one of a pyrrole skeleton, a furan skeleton, and a thiophene skeleton in the ring, and specifically, it is preferable that it is a carbazole ring, a dibenzothiophene ring, or a ring in which an aromatic ring or a heteroaromatic ring is further condensed to them.
  • the organic compound having such hole transport properties preferably has any one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton.
  • the organic compound may be an aromatic amine having a substituent containing a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine having a naphthalene ring, or an aromatic monoamine in which a 9-fluorenyl group is bonded to the nitrogen of the amine via an arylene group.
  • the organic compound having hole transport properties is a substance having an N,N-bis(4-biphenyl)amino group, since this allows the fabrication of a light-emitting device with a long life.
  • organic compounds having the above-mentioned hole transport properties include N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[ b]naphtho[1,2-d]furan-8-yl)-4"-phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d
  • aromatic amine compounds such as N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), 4,4'-bis(N- ⁇ 4-[N'-(3-methylphenyl)-N'-phenylamino]phenyl ⁇ -N-phenylamino)biphenyl (abbreviation: DNTPD), and 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B) can also be used as materials having hole transport properties.
  • DTDPPA 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl
  • the hole injection layer 111 By forming the hole injection layer 111, the hole injection properties are improved, and a light-emitting device with a low driving voltage can be obtained.
  • organic compounds that have acceptor properties are easy to vapor-deposit and form into films, making them easy to use materials.
  • the hole transport layer 112 is formed containing an organic compound having a hole transport property.
  • the organic compound having a hole transport property preferably has a hole mobility of 1 ⁇ 10 ⁇ 6 cm 2 /Vs or more.
  • the above-mentioned materials having hole transport properties include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), N,N'-bis(9,9'-spirobi[9H-fluorene]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (abbreviation: BPAFLP), and 4-phenyl-3'-(9-phenylfluorene-9-yl)triphenylamine.
  • NPB 4,4'-bis[N-(1-naphthyl)-
  • PCBA1BP 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine
  • PCBBi1BP 4,4'-diphenyl-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine
  • PCBANB 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine
  • PCBNBB 4,4'-di(1-naphthyl)-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine
  • PCBNBB 9,9-dimethyl-N-phenyl-N-[ Compounds having an aromatic amine skeleton such as 4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine
  • compounds having an aromatic amine skeleton and compounds having a carbazole skeleton are preferable because they have good reliability, high hole transportability, and contribute to reducing the driving voltage.
  • the substances listed as materials having hole transport properties that are used in the composite material of the hole injection layer 111 can also be suitably used as materials that constitute the hole transport layer 112.
  • the light-emitting layer 113 is a layer containing a light-emitting material, and preferably contains a light-emitting material and a host material.
  • the light-emitting layer may also contain other materials at the same time. It may also be a laminate of two layers with different compositions.
  • the luminescent material may be a fluorescent material, a phosphorescent material, a material that exhibits thermally activated delayed fluorescence (TADF), or any other luminescent material.
  • TADF thermally activated delayed fluorescence
  • Examples of materials that can be used as fluorescent substances in the light-emitting layer include the following. Other fluorescent substances can also be used.
  • condensed aromatic diamine compounds such as pyrene diamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPrn-03, are preferred because they have high hole trapping properties and excellent luminous efficiency or reliability.
  • DABNA1 5,9-diphenyl-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene
  • DABNA2 9-(biphenyl-3-yl)-N,N,5,11-tetraphenyl-5,9-dihydro-5,9-diaza-13b-boranaphtho[3,2,1-de]anthracene-3-amine
  • DABNA2 2,12-di(tert-butyl)-5,9-di(4-tert-butylphenyl)-N,N-diphenyl-5H,9H-[1,4]benzazaborino[2,3,4-kl]phenazaborine -7-amine
  • DPhA-tBu4DABNA 2,12-di(tert-butyl)-N,N,5,9-tetra(4-tert-butylphenyl)-5
  • a phosphorescent material As the light-emitting material in the light-emitting layer, examples of materials that can be used include the following:
  • Organometallic iridium complexes having a 4H-triazole skeleton such as tris ⁇ 2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl- ⁇ N2]phenyl- ⁇ C ⁇ iridium(III) (abbreviation: [Ir(mpptz-dmp) 3 ]) and tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Mptz) 3 ]), tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(Mptz1-mp) 3] ) organometallic iridium complexes having a 1H-triazole skeleton, such as tris(1-methyl-5-
  • tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) 3 ]), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) 3 ]), (acetylacetonato)bis(6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) 2 (acac)]), (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) 2 (acac)]), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm
  • organometallic iridium complexes having a pyrimidine skeleton are particularly preferred because they are also remarkably excellent in reliability or luminous efficiency.
  • organometallic iridium complexes having a pyrimidine skeleton such as (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: [Ir(5mdppm) 2 (dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(5mdppm) 2 (dpm)]), and bis[4,6-di(naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(d1npm) 2 (dpm)]), (acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: [Ir(
  • organometallic iridium complexes having a pyridine skeleton such as [ru- ⁇ C]iridium(III)
  • platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP)
  • rare earth metal complexes such as tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM) 3 (Phen)]) and tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: [Eu(TTA) 3 (Phen)])
  • PtOEP platinum complexes
  • rare earth metal complexes such as tris(1,3-diphenyl-1,3-prop
  • an organometallic iridium complex having a pyrazine skeleton can emit red light with good chromaticity.
  • known phosphorescent compounds may be selected and used.
  • TADF materials examples include fullerene and its derivatives, acridine and its derivatives, eosin derivatives, etc. Also included are metal-containing porphyrins that contain magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd), etc.
  • Mg magnesium
  • Zn zinc
  • Cd cadmium
  • Sn tin
  • Pt platinum
  • In indium
  • Pd palladium
  • metal-containing porphyrin examples include protoporphyrin-tin fluoride complex ( SnF2 (Proto IX)), mesoporphyrin-tin fluoride complex ( SnF2 (Meso IX)), hematoporphyrin-tin fluoride complex ( SnF2 (Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex ( SnF2 (Copro III-4Me)), octaethylporphyrin-tin fluoride complex ( SnF2 (OEP)), etioporphyrin-tin fluoride complex ( SnF2 (Etio I)), and octaethylporphyrin-platinum chloride complex ( PtCl2 OEP), which are shown in the following structural formulas.
  • the heterocyclic compound has a ⁇ -electron rich heteroaromatic ring and a ⁇ -electron deficient heteroaromatic ring, and therefore has high electron transport and hole transport properties, and is therefore preferred.
  • the skeletons having a ⁇ -electron deficient heteroaromatic ring the pyridine skeleton, the diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), and the triazine skeleton are preferred because they are stable and reliable.
  • the benzofuropyrimidine skeleton, the benzothienopyrimidine skeleton, the benzofuropyrazine skeleton, and the benzothienopyrazine skeleton are preferred because they have high acceptor properties and good reliability.
  • the skeletons having a ⁇ -electron rich heteroaromatic ring are preferred because they are stable and reliable, and therefore at least one of these skeletons is preferred.
  • dibenzofuran skeleton is preferred as the furan skeleton
  • dibenzothiophene skeleton is preferred as the thiophene skeleton.
  • pyrrole skeleton an indole skeleton, a carbazole skeleton, an indolocarbazole skeleton, a bicarbazole skeleton, and a 3-(9-phenyl-9H-carbazole-3-yl)-9H-carbazole skeleton are particularly preferred.
  • a substance in which a ⁇ -electron-rich heteroaromatic ring and a ⁇ -electron-deficient heteroaromatic ring are directly bonded is particularly preferred because the electron donating property of the ⁇ -electron-rich heteroaromatic ring and the electron accepting property of the ⁇ -electron-deficient heteroaromatic ring are both strong, and the energy difference between the S1 level and the T1 level is small, so that thermally activated delayed fluorescence can be efficiently obtained.
  • an aromatic ring to which an electron-withdrawing group such as a cyano group is bonded may be used instead of the ⁇ -electron-deficient heteroaromatic ring.
  • an aromatic amine skeleton, a phenazine skeleton, or the like can be used as the ⁇ -electron-rich skeleton.
  • examples of the ⁇ -electron-deficient skeleton include a xanthene skeleton, a thioxanthene dioxide skeleton, an oxadiazole skeleton, a triazole skeleton, an imidazole skeleton, an anthraquinone skeleton, a boron-containing skeleton such as phenylborane or boranthrene, an aromatic ring having a nitrile group or a cyano group such as benzonitrile or cyanobenzene, a heteroaromatic ring, a carbonyl skeleton such as benzophenone, a phosphine oxide skeleton, and a sulfone skeleton.
  • a ⁇ -electron-deficient skeleton and a ⁇ -electron-rich skeleton can be used in place of at least one of a ⁇ -electron-deficient heteroaromatic ring and a ⁇ -electron-rich heteroaromatic ring.
  • the TADF material is a material that has a small difference between the S 1 level and the T 1 level and has a function of converting energy from triplet excitation energy to singlet excitation energy by reverse intersystem crossing. Therefore, triplet excitation energy can be upconverted (reverse intersystem crossing) to singlet excitation energy by a small amount of thermal energy, and a singlet excitation state can be efficiently generated. In addition, triplet excitation energy can be converted into light emission.
  • an exciplex also called an exciplex
  • an exciplex which forms an excited state with two types of substances, has an extremely small difference between the S1 level and the T1 level and functions as a TADF material that can convert triplet excitation energy into singlet excitation energy.
  • a phosphorescence spectrum observed at a low temperature may be used.
  • a tangent line is drawn at the short wavelength side of the fluorescent spectrum of the TADF material, and the energy of the wavelength of the extrapolated line is taken as the S1 level
  • a tangent line is drawn at the short wavelength side of the phosphorescence spectrum of the TADF material, and the energy of the wavelength of the extrapolated line is taken as the T1 level
  • the difference between the S1 and T1 levels is preferably 0.3 eV or less, and more preferably 0.2 eV or less.
  • the S1 level of the host material is preferably higher than the S1 level of the TADF material, and the T1 level of the host material is preferably higher than the T1 level of the TADF material.
  • various carrier transport materials such as materials having electron transport properties and/or materials having hole transport properties, and the above-mentioned TADF materials can be used.
  • organic compounds having an amine skeleton or a ⁇ -electron-rich heteroaromatic ring skeleton are preferred.
  • a condensed aromatic ring containing at least one of an acridine skeleton, a phenoxazine skeleton, a phenothiazine skeleton, a furan skeleton, a thiophene skeleton, and a pyrrole skeleton is preferred, and specifically, a carbazole ring, a dibenzothiophene ring, or a ring in which an aromatic ring or a heteroaromatic ring is further condensed to the above is preferred.
  • the organic compound having such hole transport properties preferably has any one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton.
  • the organic compound may be an aromatic amine having a substituent containing a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine having a naphthalene ring, or an aromatic monoamine in which a 9-fluorenyl group is bonded to the nitrogen of the amine via an arylene group.
  • the organic compound having hole transport properties is a substance having an N,N-bis(4-biphenyl)amino group, since this allows the fabrication of a light-emitting device with a long life.
  • organic compounds examples include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviation: TPD), N,N'-bis(9,9'-spirobi[9H-fluorene]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluorene-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9 -phenyl-9H-carbazol-3-
  • compounds having an aromatic amine skeleton or a carbazole skeleton are preferable because they have good reliability, high hole transportability, and contribute to reducing the driving voltage.
  • organic compounds listed as examples of materials having hole transport properties for the hole transport layer can also be used.
  • Examples of materials having electron transport properties include metal complexes such as bis(10-hydroxybenzo[h]quinolinato)beryllium( II ) (abbreviation: BeBq), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), and organic compounds having a ⁇ -electron-deficient heteroaromatic ring.
  • metal complexes such as bis(10-hydroxybenzo[h]quinolinato)beryllium( II ) (abbreviation: BeBq), bis(2-methyl-8-quinolinolato
  • organic compounds having a ⁇ -electron-deficient heteroaromatic ring skeleton include organic compounds containing a heteroaromatic ring having a polyazole skeleton, organic compounds containing a heteroaromatic ring having a pyridine skeleton, organic compounds containing a heteroaromatic ring having a diazine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton.
  • organic compounds containing a heteroaromatic ring having a diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), organic compounds containing a heteroaromatic ring having a pyridine skeleton, and organic compounds containing a heteroaromatic ring having a triazine skeleton are preferred because of their high reliability.
  • organic compounds containing a heteroaromatic ring having a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing a heteroaromatic ring having a triazine skeleton have high electron transport properties and contribute to reducing the driving voltage.
  • benzofuropyrimidine skeletons benzothienopyrimidine skeletons, benzofuropyrazine skeletons, and benzothienopyrazine skeletons are preferred because of their high acceptor properties and high reliability.
  • organic compounds having a ⁇ -electron-deficient heteroaromatic ring skeleton include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazo organic compounds having an azole skeleton, such as 3,5-bis[3-(9H-carbazole) (abbreviation: CO11), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H
  • organic compounds having a heteroaromatic ring having a diazine skeleton, organic compounds having a heteroaromatic ring having a pyridine skeleton, and organic compounds having a heteroaromatic ring having a triazine skeleton are preferable because of their good reliability.
  • organic compounds containing heteroaromatic rings with a diazine (pyrimidine or pyrazine) skeleton and organic compounds containing heteroaromatic rings with a triazine skeleton have high electron transport properties and contribute to reducing the driving voltage.
  • TADF material As a TADF material that can be used as a host material, the same TADF materials listed above can be used.
  • a TADF material When a TADF material is used as a host material, triplet excitation energy generated in the TADF material is converted to singlet excitation energy by reverse intersystem crossing, and the energy is further transferred to a light-emitting substance, thereby improving the light-emitting efficiency of the light-emitting device.
  • the TADF material functions as an energy donor, and the light-emitting substance functions as an energy acceptor.
  • the luminescent material is a fluorescent luminescent material.
  • the S1 level of the TADF material is higher than the S1 level of the fluorescent luminescent material.
  • the T1 level of the TADF material is higher than the S1 level of the fluorescent luminescent material. Therefore, it is preferable that the T1 level of the TADF material is higher than the T1 level of the fluorescent luminescent material.
  • TADF material that emits light that overlaps with the wavelength of the lowest energy absorption band of the fluorescent material. This is preferable because it allows for smooth transfer of excitation energy from the TADF material to the fluorescent material, resulting in efficient emission.
  • the TADF material in order to efficiently generate singlet excitation energy from triplet excitation energy by reverse intersystem crossing, it is preferable that carrier recombination occurs in the TADF material. In addition, it is preferable that the triplet excitation energy generated in the TADF material does not move to the triplet excitation energy of the fluorescent material.
  • the fluorescent material has a protective group around the luminophore (skeleton causing light emission) of the fluorescent material.
  • a substituent having no ⁇ bond is preferable, and a saturated hydrocarbon is preferable, specifically, an alkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, and a trialkylsilyl group having 3 to 10 carbon atoms are mentioned, and it is more preferable that there are multiple protective groups. Since a substituent having no ⁇ bond has poor function of transporting carriers, the distance between the TADF material and the luminophore of the fluorescent material can be increased without affecting carrier transport or carrier recombination.
  • the luminophore refers to an atomic group (skeleton) causing light emission in the fluorescent material.
  • the luminophore preferably has a skeleton having a ⁇ bond, preferably contains an aromatic ring, and preferably has a condensed aromatic ring or a condensed heteroaromatic ring.
  • luminophores include a phenanthrene skeleton, a stilbene skeleton, an acridone skeleton, a phenoxazine skeleton, a phenothiazine skeleton, a naphthalene skeleton, an anthracene skeleton, a fluorene skeleton, a chrysene skeleton, a triphenylene skeleton, a tetracene skeleton, a pyrene skeleton, a perylene skeleton, a coumarin skeleton, a quinacridone skeleton, and a naphthobisbenzofuran skeleton.
  • fluorescent substances having a naphthalene skeleton, an anthracene skeleton, a fluorene skeleton, a chrysene skeleton, a triphenylene skeleton, a tetracene skeleton, a pyrene skeleton, a perylene skeleton, a coumarin skeleton, a quinacridone skeleton, and a naphthobisbenzofuran skeleton are preferred because they have a high fluorescence quantum yield.
  • a material having an anthracene skeleton is suitable as the host material.
  • a substance having an anthracene skeleton is used as the host material of a fluorescent emitting substance, it is possible to realize an emitting layer with good luminous efficiency and durability.
  • a substance having an anthracene skeleton to be used as a host material a substance having a diphenylanthracene skeleton, particularly a 9,10-diphenylanthracene skeleton, is preferable because it is chemically stable.
  • the host material has a carbazole skeleton
  • the host material contains a dibenzocarbazole skeleton, it is preferable because the HOMO level is about 0.1 eV shallower than carbazole, making it easier for holes to enter, and it also has excellent hole transport properties and high heat resistance.
  • a more preferable host material is a substance having both a 9,10-diphenylanthracene skeleton and a carbazole skeleton (or a benzocarbazole skeleton or a dibenzocarbazole skeleton). Note that, in view of the hole injection/transport property, a benzofluorene skeleton or a dibenzofluorene skeleton may be used instead of the carbazole skeleton.
  • Such substances include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 3-[4-(1-naphthyl)phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-[4-(9-phenyl-9H-flu
  • the host material may be a mixture of a plurality of substances. When a mixture of host materials is used, it is preferable to mix a material having electron transport properties with a material having hole transport properties. By mixing a material having electron transport properties with a material having hole transport properties, the transport properties of the light-emitting layer 113 can be easily adjusted, and the recombination region can be easily controlled.
  • the weight ratio of the content of the material having hole transport properties to the material having electron transport properties may be 1:19 to 19:1 (material having hole transport properties: material having electron transport properties).
  • a phosphorescent material can be used as part of the mixed material.
  • the phosphorescent material can be used as an energy donor that provides excitation energy to a fluorescent material when the fluorescent material is used as a light-emitting material.
  • these mixed materials may form an exciplex. It is preferable to select a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest energy absorption band of the light-emitting material, because this allows for smooth energy transfer and efficient emission. In addition, the use of this configuration is preferable because it reduces the driving voltage.
  • At least one of the materials forming the exciplex may be a phosphorescent material. This allows the triplet excitation energy to be efficiently converted into singlet excitation energy by reverse intersystem crossing.
  • the HOMO level of the material having hole transport properties is equal to or higher than the HOMO level of the material having electron transport properties. It is also preferable that the LUMO level of the material having hole transport properties is equal to or higher than the LUMO level of the material having electron transport properties.
  • the LUMO level and HOMO level of the material can be derived from the electrochemical properties (reduction potential and oxidation potential) of the material measured by cyclic voltammetry (CV) measurement.
  • the formation of an exciplex can be confirmed, for example, by comparing the emission spectrum of a material having hole transport properties, the emission spectrum of a material having electron transport properties, and the emission spectrum of a mixed film obtained by mixing these materials, and observing the phenomenon in which the emission spectrum of the mixed film shifts to a longer wavelength than the emission spectrum of each material (or has a new peak on the longer wavelength side).
  • transient photoluminescence (PL) of a material having hole transport properties the transient PL of a material having electron transport properties, and the transient PL of a mixed film obtained by mixing these materials, and observing the difference in transient response, such as the transient PL lifetime of the mixed film having a longer lifetime component than the transient PL lifetime of each material, or the proportion of delayed components becoming larger.
  • the above-mentioned transient PL may be read as transient electroluminescence (EL).
  • the formation of an exciplex can also be confirmed by comparing the transient EL of a material having hole transport properties, the transient EL of a material having electron transport properties, and the transient EL of a mixed film obtained by mixing these materials, and observing the difference in transient response.
  • the electron transport layer 114 may have a laminated structure. When the electron transport layer 114 has a laminated structure, it is preferable that all the laminated layers have the structure shown in embodiment 1.
  • the electron injection layer 115 is formed between the electron transport layer 114 and the second electrode 102.
  • the configuration of the electron injection layer 115 has been described in detail in embodiment 1, so repeated description will be omitted.
  • the second electrode 102 is an electrode including a cathode.
  • the second electrode 102 may have a laminated structure, in which case the layer in contact with the EL layer 103 functions as the cathode.
  • a material for forming the cathode a metal, an alloy, an electrically conductive compound, and a mixture thereof having a small work function (specifically, 3.8 eV or less) can be used.
  • cathode material examples include alkali metals such as lithium (Li) or cesium (Cs), elements belonging to the first or second group of the periodic table such as magnesium (Mg), calcium (Ca), and strontium (Sr), and alloys (MgAg, AlLi) containing these, compounds (lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF 2 ), etc.), rare earth metals such as europium (Eu), ytterbium (Yb), and alloys containing these, etc.
  • alkali metals such as lithium (Li) or cesium (Cs)
  • elements belonging to the first or second group of the periodic table such as magnesium (Mg), calcium (Ca), and strontium (Sr), and alloys (MgAg, AlLi) containing these, compounds (lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF 2 ), etc.
  • the electron injection layer 115 or a thin film of the above-mentioned material having a small work function between the second electrode 102 and the electron transport layer various conductive materials such as Al, Ag, ITO, indium oxide-tin oxide containing silicon or silicon oxide can be used as the cathode regardless of the magnitude of the work function.
  • a light-emitting device When the second electrode 102 is formed from a material that is transparent to visible light, a light-emitting device can be formed that emits light from the second electrode 102 side, and when the first electrode 101 is formed from a material that is transparent to visible light, a light-emitting device can be formed that emits light from the first electrode 101 side.
  • These conductive materials can be formed into films using dry methods such as vacuum deposition or sputtering, inkjet methods, spin coating methods, etc. They may also be formed using a wet method using a sol-gel method, or a wet method using a paste of a metal material.
  • the EL layer 103 can be formed by a variety of methods, including dry and wet methods. For example, vacuum deposition, gravure printing, offset printing, screen printing, inkjet printing, spin coating, and the like may be used.
  • each of the electrodes or layers described above may be formed using a different film formation method.
  • FIG. 2B An embodiment of a light-emitting device having a configuration in which multiple light-emitting units are stacked (also called a stacked device or a tandem device) will be described with reference to FIG. 2B.
  • This light-emitting device has multiple light-emitting units between an anode and a cathode.
  • One light-emitting unit has a configuration substantially similar to that of the EL layer 103 shown in FIG. 2A.
  • the light-emitting device shown in FIG. 2B is a light-emitting device having multiple light-emitting units, and the light-emitting device shown in FIG. 2A can be said to be a light-emitting device having one light-emitting unit.
  • a first light-emitting unit 511 and a second light-emitting unit 512 are stacked between a first electrode 501 and a second electrode 502, and an intermediate layer 116 is provided between the first light-emitting unit 511 and the second light-emitting unit 512.
  • the first electrode 501 and the second electrode 502 correspond to the first electrode 101 and the second electrode 102 in FIG. 2A, respectively, and the same as described in the explanation of FIG. 2A can be applied.
  • the first light-emitting unit 511 and the second light-emitting unit 512 may have the same configuration or different configurations.
  • the intermediate layer 116 has a function of injecting electrons into one light-emitting unit and injecting holes into the other light-emitting unit when a voltage is applied between the first electrode 501 and the second electrode 502. That is, in FIG. 2B, when a voltage is applied so that the potential of the anode is higher than the potential of the cathode, the intermediate layer 116 only needs to inject electrons into the first light-emitting unit 511 and inject holes into the second light-emitting unit 512.
  • the intermediate layer 116 includes a charge generation layer.
  • the charge generation layer also includes at least a P-type layer 117.
  • the P-type layer 117 is preferably formed using the composite material listed above as a material that can form the hole injection layer 111.
  • the P-type layer 117 may also be formed by laminating a film containing the acceptor material and a film containing a hole transport material, both of which are materials that form the composite material. By applying a potential to the P-type layer 117, electrons are injected into the electron transport layer 114 and holes are injected into the cathode, and the light-emitting device operates.
  • the intermediate layer 116 has one or both of an electronic relay layer 118 and an N-type layer 119 in addition to the P-type layer 117.
  • the electron relay layer 118 contains at least a substance having electron transport properties, and has a function of preventing interaction between the N-type layer 119 and the P-type layer 117 and smoothly transferring electrons.
  • the LUMO level of the substance having electron transport properties contained in the electron relay layer 118 is preferably between the LUMO level of the acceptor substance in the P-type layer 117 and the LUMO level of the substance contained in the layer in contact with the intermediate layer 116 in the electron transport layer 114.
  • the specific energy level of the LUMO level of the substance having electron transport properties used in the electron relay layer 118 is -5.0 eV or more, preferably -5.0 eV or more and -3.0 eV or less. Note that it is preferable to use a phthalocyanine-based material or a metal complex having a metal-oxygen bond and an aromatic ligand as the substance having electron transport properties used in the electron relay layer 118.
  • the N-type layer 119 can be made of a material with high electron injection properties, such as alkali metals, alkaline earth metals, rare earth metals, and their compounds (alkali metal compounds (including oxides such as lithium oxide, halides, and carbonates such as lithium carbonate and cesium carbonate), alkaline earth metal compounds (including oxides, halides, and carbonates), or rare earth metal compounds (including oxides, halides, and carbonates)).
  • alkali metal compounds including oxides such as lithium oxide, halides, and carbonates such as lithium carbonate and cesium carbonate
  • alkaline earth metal compounds including oxides, halides, and carbonates
  • rare earth metal compounds including oxides, halides, and carbonates
  • the donor substance may be an alkali metal, an alkaline earth metal, a rare earth metal, or a compound thereof (an alkali metal compound (including an oxide such as lithium oxide, a halide, or a carbonate such as lithium carbonate or cesium carbonate), an alkaline earth metal compound (including an oxide, a halide, or a carbonate), or a rare earth metal compound (including an oxide, a halide, or a carbonate)), or an organic compound such as tetrathianaphthacene (abbreviation: TTN), nickelocene, or decamethylnickelocene.
  • TTN tetrathianaphthacene
  • nickelocene nickelocene
  • decamethylnickelocene the substance having electron transport properties may be formed using a material similar to the material constituting the electron transport layer 114 described above.
  • a layer containing a highly basic organic compound which was described in the first embodiment as being used for the electron injection layer, may be formed at the same position as the N-type layer 119. Even with this configuration, a tandem-type light-emitting device can be fabricated.
  • the strongly basic organic compound does not function as a donor, so no electrons are generated in the layer containing the strongly basic organic compound (hereinafter, this layer is referred to as the DLL).
  • this layer is referred to as the DLL.
  • holes injected from the anode into the first light-emitting unit accumulate in the DLL or between the light-emitting layer of the first light-emitting unit and the electron transport layer.
  • the electrons induced in the P-type layer 117 accumulate at the interface on the DLL side of the P-type layer 117 (if the DLL does not contain a material with electron transport properties, i.e., in the case of a single film of an organic compound with strong basicity, the electrons generated in the P-type layer 117 accumulate on the single film side of the organic compound with strong basicity).
  • the accumulated electrons form an electric double layer together with the holes accumulated between the DLL or the light-emitting layer of the first light-emitting unit and the electron transport layer, and an electric dipole is generated.
  • a light-emitting device that uses a DLL containing a strongly basic organic compound instead of N-type layer 119 can function as a tandem light-emitting device.
  • the electron transport layer of the first light-emitting unit 511 is preferably bipolar.
  • the DLL contains an organic compound having a strong basicity with an acid dissociation constant pKa of 8 or more, thereby trapping and blocking holes, and the electron transport layer has bipolarity, so that holes are quickly transported to the DLL, thereby realizing a reduction in the driving voltage.
  • the electron transport layer of the first light-emitting unit 511 may be a mixed layer of an organic compound having electron transport properties and an organic compound having hole transport properties, as in the electron injection layer described in embodiment 1, but a single substance having both electron transport properties and hole transport properties is preferable because it is possible to obtain a tandem light-emitting device with good characteristics.
  • the substance having both electron transport properties and hole transport properties is preferably an organic compound having both a skeleton having electron transport properties and a skeleton having hole transport properties.
  • the skeleton having electron transport properties is preferably a ⁇ -electron deficient heteroaromatic ring skeleton
  • the skeleton having hole transport properties is preferably a ⁇ -electron rich heteroaromatic ring skeleton or an arylamine skeleton.
  • the charge generation layer of the intermediate layer 116 can also function as the hole injection layer of the light-emitting unit, so the light-emitting unit does not need to have a hole injection layer.
  • the intermediate layer 116 can also function as the electron injection layer of the light-emitting unit, so the light-emitting unit does not need to have an electron injection layer.
  • FIG. 2B a light-emitting device having two light-emitting units is described, but the same can be applied to a light-emitting device having three or more light-emitting units stacked together.
  • each light-emitting unit by making the emission colors of each light-emitting unit different, it is possible to obtain light emission of a desired color from the light-emitting device as a whole. For example, in a light-emitting device having two light-emitting units, it is possible to obtain a light-emitting device that emits white light as a whole by obtaining red and green emission colors from the first light-emitting unit and blue emission color from the second light-emitting unit.
  • each layer and electrode such as the above-mentioned EL layer 103, the first light-emitting unit 511, the second light-emitting unit 512, and the intermediate layer can be formed using, for example, a deposition method (including a vacuum deposition method), a droplet discharge method (also called an inkjet method), a coating method, a gravure printing method, or the like. Furthermore, they may include a low molecular weight material, a medium molecular weight material (including an oligomer and a dendrimer), or a polymer material.
  • Figure 3A shows two adjacent light-emitting devices (light-emitting device 130a and light-emitting device 130b) included in a display device according to one embodiment of the present invention.
  • the light-emitting device 130a has an EL layer 103a between a first electrode 101a on an insulating layer 175 and an opposing second electrode 102.
  • the EL layer 103a has a structure having a hole injection layer 111a, a hole transport layer 112a, a light-emitting layer 113a, an electron transport layer 114a, and an electron injection layer 115a, but may have a different laminate structure.
  • Light-emitting device 130b has an EL layer 103b between a first electrode 101b on insulating layer 175 and an opposing second electrode 102.
  • EL layer 103b has a configuration having hole injection layer 111b, hole transport layer 112b, light-emitting layer 113b, electron transport layer 114b, and electron injection layer 115b, but may have a different laminate structure.
  • the configurations of the electron transport layer 114a and the electron injection layer 115a in the light-emitting device 130a, and the configurations of the electron transport layer 114b and the electron injection layer 115b in the light-emitting device 130b are preferably as described in embodiment 1.
  • the second electrode 102 is preferably a continuous layer shared by the light-emitting devices 130a and 130b.
  • the EL layers 103a and 103b are independent of each other because they are processed by photolithography after the electron injection layers 115a and 115b are formed.
  • the edge (outline) of the EL layer 103a is roughly aligned in the vertical direction to the substrate because it is processed by photolithography.
  • the edge (outline) of the EL layer 103b is roughly aligned in the vertical direction to the substrate because it is processed by photolithography.
  • the EL layer 103a and the EL layer 103d are processed by photolithography, a gap d exists between the EL layer 103a and the EL layer 103d.
  • the distance between the first electrode 101c and the first electrode 101d can be made smaller than when performing mask deposition, and can be set to 2 ⁇ m or more and 5 ⁇ m or less.
  • Figure 3B shows two adjacent tandem-type light-emitting elements (light-emitting device 130c, light-emitting device 130d) fabricated by photolithography.
  • the light-emitting device 130c has an EL layer 103c between the first electrode 101c and the second electrode 102 on the insulating layer 175.
  • the EL layer 103c has a configuration in which a first light-emitting unit 511c and a second light-emitting unit 512c are stacked with an intermediate layer 116c sandwiched between them. Note that, although an example in which two light-emitting units are stacked is shown in FIG. 3, a configuration in which three or more light-emitting units are stacked may also be used.
  • the first light-emitting unit 511c has a hole injection layer 111c, a first hole transport layer 112c_1, a first light-emitting layer 113c_1, and a first electron transport layer 114c_1.
  • the intermediate layer 116c has a P-type layer 117c, an electron relay layer 118c, and an N-type layer 119c.
  • the electron relay layer 118c may or may not be present.
  • the second light-emitting unit 512c has a second hole transport layer 112c_2, a second light-emitting layer 113c_2, a second electron transport layer 114c_2, and an electron injection layer 115.
  • the light-emitting device 130d has an EL layer 103d between the first electrode 101d and the second electrode 102 on the insulating layer 175.
  • the EL layer 103d has a configuration in which a first light-emitting unit 511d and a second light-emitting unit 512d are stacked with an intermediate layer 116d sandwiched between them. Note that, although an example in which two light-emitting units are stacked is shown in FIG. 3, a configuration in which three or more light-emitting units are stacked may also be used.
  • the first light-emitting unit 511d has a hole injection layer 111d, a first hole transport layer 112d_1, a first light-emitting layer 113d_1, and a first electron transport layer 114d_1.
  • the intermediate layer 116d has a P-type layer 117d, an electron relay layer 118d, and an N-type layer 119d.
  • the electron relay layer 118d may or may not be present.
  • the second light-emitting unit 512d has a second hole transport layer 112d_2, a second light-emitting layer 113d_2, a second electron transport layer 114d_2, and an electron injection layer 115.
  • the second electron transport layer 114c_1 and the electron injection layer 115c and the second electron transport layer 114d_1 and the electron injection layer 115d preferably have the configurations described in embodiment 1.
  • the second electrode 102 is preferably a continuous layer shared by the light-emitting devices 130c and 130d.
  • the EL layers 103c and 103d are independent of each other because they are processed by photolithography after the electron injection layer 115c and the electron injection layer 115d are formed, respectively.
  • the edge (outline) of the EL layer 103c is roughly aligned in the vertical direction to the substrate because it is processed by photolithography.
  • the edge (outline) of the EL layer 103d is roughly aligned in the vertical direction to the substrate because it is processed by photolithography.
  • the distance between the first electrode 101c and the first electrode 101d can be made smaller than when performing mask vapor deposition, and can be set to 2 ⁇ m or more and 5 ⁇ m or less.
  • the light-emitting element of one embodiment of the present invention can be processed with sufficient precision to manufacture a high-definition display device because the organic compound layer is processed by photolithography.
  • the lithography process can be performed on the electron injection layer far from the light-emitting layer without contamination by alkali metals, so that the light-emitting element can have good characteristics.
  • the light-emitting element of one embodiment of the present invention having such a structure can realize a high-definition display device and can have good characteristics.
  • the organic compound layer in the light-emitting element of one embodiment of the present invention is processed at once by photolithography, so that the contours of all layers included in the organic compound layer are approximately the same.
  • approximately the same in this specification means that the deviation between contour A of layer A and contour B of layer B included in the organic compound layer is within 5% of the width of the organic compound layer on a line perpendicular to the contours of the portions being compared.
  • the end face of the organic compound layer has a tapered shape, continuous changes in the contour are permitted.
  • multiple light-emitting devices 130 are formed on an insulating layer 175 to form a display device.
  • the display device has a pixel section 177 in which a plurality of pixels 178 are arranged in a matrix.
  • the pixel 178 has sub-pixels 110R, 110G, and 110B.
  • subpixel 110R when describing matters common to, for example, subpixel 110R, subpixel 110G, and subpixel 110B, they may be referred to as subpixel 110.
  • subpixel 110 when describing matters common to other components distinguished by alphabets, they may be described using symbols without the alphabet.
  • Subpixel 110R emits red light
  • subpixel 110G emits green light
  • subpixel 110B emits blue light. This allows an image to be displayed in pixel section 177.
  • subpixels of three colors, red (R), green (G), and blue (B) are described as an example, but combinations of subpixels of other colors may be used.
  • the number of subpixels is not limited to three, and may be four or more. Examples of the four subpixels include subpixels of four colors, R, G, B, and white (W), subpixels of four colors, R, G, B, and Y, and subpixels of R, G, B, and infrared light (IR).
  • the row direction may be referred to as the X direction
  • the column direction may be referred to as the Y direction.
  • the X direction and the Y direction intersect, for example, perpendicularly.
  • FIG. 4A shows an example in which subpixels of different colors are arranged side by side in the X direction, and subpixels of the same color are arranged side by side in the Y direction. Note that subpixels of different colors may also be arranged side by side in the Y direction, and subpixels of the same color may also be arranged side by side in the X direction.
  • a connection section 140 may be provided outside the pixel section 177, and a region 141 may be provided.
  • the region 141 is provided between the pixel section 177 and the connection section 140.
  • the EL layer 103 is provided in the region 141.
  • the conductive layer 151C is provided in the connection section 140.
  • FIG. 4A an example is shown in which the region 141 and the connection portion 140 are located to the right of the pixel portion 177, but the positions of the region 141 and the connection portion 140 are not particularly limited.
  • the region 141 and the connection portion 140 may be singular or multiple.
  • FIG. 4B is an example of a cross-sectional view between dashed lines A1-A2 in FIG. 4A.
  • the display device has an insulating layer 171, a conductive layer 172 on the insulating layer 171, an insulating layer 173 on the insulating layer 171 and on the conductive layer 172, an insulating layer 174 on the insulating layer 173, and an insulating layer 175 on the insulating layer 174.
  • the insulating layer 171 is provided on a substrate (not shown).
  • An opening reaching the conductive layer 172 is provided in the insulating layer 175, the insulating layer 174, and the insulating layer 173, and a plug 176 is provided to fill the opening.
  • the light-emitting device 130 is provided on the insulating layer 175 and the plug 176.
  • a protective layer 131 is provided to cover the light-emitting device 130.
  • the substrate 120 is bonded to the protective layer 131 by a resin layer 122.
  • an inorganic insulating layer 125 and an insulating layer 127 on the inorganic insulating layer 125 are provided between adjacent light-emitting devices 130.
  • FIG. 4B multiple cross sections of the inorganic insulating layer 125 and the insulating layer 127 are shown, but when the display device is viewed from above, it is preferable that the inorganic insulating layer 125 and the insulating layer 127 are each connected to one another. In other words, it is preferable that the insulating layer 127 is an insulating layer having an opening on the first electrode.
  • the light-emitting devices 130 are light-emitting device 130R, light-emitting device 130G, and light-emitting device 130B.
  • the light-emitting devices 130R, 130G, and 130B emit light of different colors.
  • the light-emitting device 130R can emit red light
  • the light-emitting device 130G can emit green light
  • the light-emitting device 130B can emit blue light.
  • the light-emitting device 130R, the light-emitting device 130G, or the light-emitting device 130B may also emit other visible light or infrared light.
  • the display device of one embodiment of the present invention can be, for example, a top-emission type that emits light in the direction opposite to the substrate on which the light-emitting device is formed. Note that the display device of one embodiment of the present invention may be a bottom-emission type.
  • the light-emitting device 130R has a configuration as shown in the first and second embodiments. It has a first electrode 101R (pixel electrode) consisting of a conductive layer 151R and a conductive layer 152R, an EL layer 103R on the first electrode 101R, and a second electrode 102 (common electrode) on the EL layer 103R.
  • the electron injection layer which is the outermost layer of the EL layer 103R, has a configuration as described in the first embodiment. With this configuration, damage to the light-emitting layer or active layer in the photolithography process can be suppressed, and good film quality and electrical characteristics can be expected.
  • the electron transport layer is a mixed layer of an organic compound having electron transport properties and an organic compound having hole transport properties, it is possible to provide a display device in which the increase in driving voltage is suppressed.
  • the light-emitting device 130G has a configuration as shown in the first and second embodiments. It has a first electrode 101G (pixel electrode) consisting of a conductive layer 151G and a conductive layer 152G, an EL layer 103G on the first electrode 101G, and a second electrode 102 (common electrode) on the EL layer 103G.
  • the electron injection layer which is the outermost layer of the EL layer 103G, has a configuration as described in the first embodiment. With this configuration, damage to the light-emitting layer or active layer in the photolithography process can be suppressed, and good film quality and electrical characteristics can be expected.
  • the electron transport layer is a mixed layer of an organic compound having electron transport properties and an organic compound having hole transport properties, it is possible to provide a display device in which the increase in driving voltage is suppressed.
  • the light-emitting device 130B has a configuration as shown in the first and second embodiments. It has a first electrode 101B (pixel electrode) consisting of a conductive layer 151B and a conductive layer 152B, an EL layer 103B on the first electrode 101B, and a second electrode 102 (common electrode) 102 on the EL layer 103B.
  • the electron injection layer which is the outermost layer of the EL layer 103B, has a configuration as described in the first embodiment. With this configuration, damage to the light-emitting layer or active layer in the photolithography process can be suppressed, and good film quality and electrical characteristics can be expected.
  • the electron transport layer is a mixed layer of an organic compound having electron transport properties and an organic compound having hole transport properties, it is possible to provide a display device in which the increase in driving voltage is suppressed.
  • the pixel electrode (first electrode) and common electrode (second electrode) of the light-emitting device one functions as an anode and the other functions as a cathode.
  • the pixel electrode functions as an anode and the common electrode functions as a cathode.
  • EL layer 103R, EL layer 103G, and EL layer 103B are independent in the shape of islands, either individually or for each emitted color. It is preferable that EL layer 103R, EL layer 103G, and EL layer 103B do not overlap with each other.
  • EL layer 103 in the shape of islands for each light-emitting device 130, leakage current between adjacent light-emitting devices 130 can be suppressed even in a high-definition display device. This makes it possible to prevent crosstalk and realize a display device with extremely high contrast. In particular, a display device with high current efficiency at low luminance can be realized.
  • the island-shaped EL layer 103 is formed by depositing an EL film and processing the EL using a photolithography method.
  • the EL layer 103 is preferably provided so as to cover the top and side surfaces of the first electrode 101 (pixel electrode) of the light-emitting device 130. This makes it easier to increase the aperture ratio of the display device compared to a configuration in which the end of the EL layer 103 is located inside the end of the pixel electrode. In addition, covering the side surfaces of the pixel electrode of the light-emitting device 130 with the EL layer 103 can prevent the pixel electrode and the second electrode 102 from coming into contact with each other, thereby preventing short circuits in the light-emitting device 130.
  • the first electrode 101 (pixel electrode) of the light-emitting device preferably has a stacked structure.
  • the first electrode 101 of the light-emitting device 130 has a stacked structure of a conductive layer 151 provided on the insulating layer 171 side and a conductive layer 152 provided on the EL layer side.
  • a metal material can be used as the conductive layer 151.
  • metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), etc., and alloys containing appropriate combinations of these metals can also be used.
  • an oxide containing one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used.
  • indium tin oxide containing silicon has a large work function, for example, a work function of 4.0 eV or more, and therefore can be suitably used as the conductive layer 152.
  • the conductive layer 151 may have a stacked structure of multiple layers having different materials, and the conductive layer 152 may have a stacked structure of multiple layers having different materials.
  • the conductive layer 151 may have a layer using a material that can be used for the conductive layer 152, such as a conductive oxide, and the conductive layer 152 may have a layer using a material that can be used for the conductive layer 151, such as a metal material.
  • the layer in contact with the conductive layer 152 may be a layer using a material that can be used for the conductive layer 152.
  • the end of the conductive layer 151 preferably has a tapered shape. Specifically, the end of the conductive layer 151 preferably has a tapered shape with a taper angle of less than 90°. In this case, the conductive layer 152 provided along the side surface of the conductive layer 151 also has a tapered shape. By making the side surface of the conductive layer 152 tapered, the coverage of the EL layer 103 provided along the side surface of the conductive layer 152 can be improved.
  • the display device has a light-emitting device 130 configured as shown in the first and second embodiments, making it possible to provide a display device with good reliability.
  • Thin films (insulating films, semiconductor films, conductive films, and the like) constituting the display device can be formed by a sputtering method, a chemical vapor deposition (CVD) method, a vacuum deposition method, a pulsed laser deposition (PLD) method, an atomic layer deposition (ALD) method, or the like.
  • CVD chemical vapor deposition
  • PLD pulsed laser deposition
  • ALD atomic layer deposition
  • the thin films (insulating films, semiconductor films, conductive films, etc.) constituting the display device can be formed by wet film formation methods such as spin coating, dipping, spray coating, inkjet, dispensing, screen printing, offset printing, doctor knife method, slit coating, roll coating, curtain coating, or knife coating.
  • the thin films that make up the display device can be processed using, for example, photolithography.
  • the light used for exposure can be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture of these.
  • ultraviolet light, KrF laser light, ArF laser light, etc. can also be used.
  • Exposure can also be performed by immersion exposure technology. Extreme ultraviolet (EUV: Extreme Ultra-violet) light or X-rays can also be used as the light used for exposure. An electron beam can also be used instead of the light used for exposure.
  • EUV Extreme Ultra-violet
  • the thin film can be etched by dry etching, wet etching, sandblasting, or other methods.
  • an insulating layer 171 is formed on a substrate (not shown).
  • a conductive layer 172 and a conductive layer 179 are formed on the insulating layer 171, and an insulating layer 173 is formed on the insulating layer 171 so as to cover the conductive layer 172 and the conductive layer 179.
  • an insulating layer 174 is formed on the insulating layer 173, and an insulating layer 175 is formed on the insulating layer 174.
  • a substrate having at least a heat resistance sufficient to withstand subsequent heat treatment can be used.
  • a glass substrate, a quartz substrate, a sapphire substrate, a ceramic substrate, an organic resin substrate, a single crystal semiconductor substrate made of silicon or silicon carbide, a polycrystalline semiconductor substrate, a compound semiconductor substrate such as silicon germanium, an SOI substrate, or other semiconductor substrates can be used.
  • openings are formed in the insulating layers 175, 174, and 173, reaching the conductive layer 172. Then, plugs 176 are formed to fill the openings.
  • a conductive film 151f which will later become conductive layers 151R, 151G, 151B, and 151C, is formed on the plug 176 and on the insulating layer 175.
  • a metal material for example, can be used as the conductive film 151f.
  • a resist mask 191 is formed on the conductive film 151f.
  • the resist mask 191 can be formed by applying a photosensitive material (photoresist) and then performing exposure and development.
  • the conductive film 151f is removed from areas that do not overlap with the resist mask 191. This forms the conductive layer 151.
  • the resist mask 191 is removed.
  • the resist mask 191 can be removed by ashing using oxygen plasma, for example.
  • insulating film 156f which will later become insulating layer 156R, insulating layer 156G, insulating layer 156B, and insulating layer 156C, is formed on conductive layer 151R, conductive layer 151G, conductive layer 151B, conductive layer 151C, and insulating layer 175.
  • the insulating film 156f can be an inorganic insulating film such as an oxide insulating film, a nitride insulating film, an oxynitride insulating film, or a nitride oxide insulating film, for example, silicon oxynitride.
  • insulating layer 156R, insulating layer 156G, insulating layer 156B, and insulating layer 156C are formed by processing insulating film 156f.
  • a conductive film 152f is formed on conductive layer 151R, conductive layer 151G, conductive layer 151B, conductive layer 151C, insulating layer 156R, insulating layer 156G, insulating layer 156B, insulating layer 156C, and insulating layer 175.
  • the conductive film 152f may be, for example, a conductive oxide.
  • the conductive film 152f may be a laminate.
  • conductive film 152f is processed to form conductive layers 152R, 152G, 152B, and 152C.
  • the organic compound film 103Rf is formed on the conductive layer 152R, the conductive layer 152G, the conductive layer 152B, and the insulating layer 175. Note that, as shown in FIG. 6C, the organic compound film 103Rf is not formed on the conductive layer 152C.
  • a sacrificial film 158Rf and a mask film 159Rf are formed.
  • a film that is highly resistant to the processing conditions of the organic compound film 103Rf specifically, a film that has a large etching selectivity with respect to the organic compound film 103Rf, is used.
  • a film that has a large etching selectivity with respect to the sacrificial film 158Rf is used.
  • the sacrificial film 158Rf and the mask film 159Rf are formed at a temperature lower than the heat resistance temperature of the organic compound film 103Rf.
  • the substrate temperature when forming the sacrificial film 158Rf and the mask film 159Rf is typically 100°C or higher and 200°C or lower, preferably 100°C or higher and 150°C or lower, and more preferably 100°C or higher and 120°C or lower.
  • the sacrificial film 158Rf formed on and in contact with the organic compound film 103Rf is preferably formed using a formation method that causes less damage to the organic compound film 103Rf than the mask film 159Rf.
  • the ALD method or the vacuum deposition method is more preferable than the sputtering method.
  • the sacrificial film 158Rf and the mask film 159Rf may each be made of one or more of a metal film, an alloy film, a metal oxide film, a semiconductor film, an organic insulating film, and an inorganic insulating film, for example.
  • the sacrificial film 158Rf and the mask film 159Rf can be made of, for example, a metal material such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or an alloy material containing such a metal material.
  • a metal material such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum
  • a low-melting point material such as aluminum or silver.
  • a metal material capable of blocking ultraviolet rays for one or both of the sacrificial film 158Rf and the mask film 159Rf, since it is possible to prevent the organic compound film 103Rf from being irradiated with ultraviolet rays during pattern exposure, thereby suppressing deterioration of the organic compound film 103Rf.
  • the sacrificial film 158Rf and the mask film 159Rf may each be made of a metal oxide such as In-Ga-Zn oxide, indium oxide, In-Zn oxide, In-Sn oxide, indium titanium oxide (In-Ti oxide), indium tin zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide), indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide), or indium tin oxide containing silicon.
  • a metal oxide such as In-Ga-Zn oxide, indium oxide, In-Zn oxide, In-Sn oxide, indium titanium oxide (In-Ti oxide), indium tin zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide), indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide), or indium tin oxide containing silicon.
  • element M (wherein M is one or more elements selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium) may be used instead of gallium.
  • the sacrificial film 158Rf and the mask film 159Rf it is preferable to use a semiconductor material such as silicon or germanium, because these materials have a high affinity with the semiconductor manufacturing process.
  • a compound containing the above semiconductor material can be used.
  • various inorganic insulating films can be used as the sacrificial film 158Rf and the mask film 159Rf.
  • an oxide insulating film is preferable because it has higher adhesion to the organic compound film 103Rf than a nitride insulating film.
  • a resist mask 190R is formed.
  • the resist mask 190R can be formed by applying a photosensitive material (photoresist) and then performing exposure and development.
  • the resist mask 190R is provided in a position overlapping with the conductive layer 152R. It is preferable that the resist mask 190R is also provided in a position overlapping with the conductive layer 152C. This can prevent the conductive layer 152C from being damaged during the manufacturing process of the display device.
  • a portion of the mask film 159Rf is removed using the resist mask 190R to form a mask layer 159R.
  • the mask layer 159R remains on the conductive layer 152R and on the conductive layer 152C.
  • the resist mask 190R is removed.
  • a portion of the sacrificial film 158Rf is removed using the mask layer 159R as a mask (also called a hard mask) to form a sacrificial layer 158R.
  • an acid aqueous solution such as a developing solution, an alkaline aqueous solution such as a tetramethylammonium hydroxide aqueous solution (TMAH), a chemical solution using dilute hydrofluoric acid, oxalic acid, phosphoric acid, acetic acid, nitric acid, or a mixture of these liquids.
  • TMAH tetramethylammonium hydroxide aqueous solution
  • Resist mask 190R can be removed in the same manner as resist mask 191.
  • the organic compound film 103Rf is processed to form the EL layer 103R.
  • the mask layer 159R and the sacrificial layer 158R are used as a hard mask to remove a portion of the organic compound film 103Rf to form the EL layer 103R.
  • a laminated structure of the EL layer 103R, the sacrificial layer 158R, and the mask layer 159R remains on the conductive layer 152R.
  • the conductive layer 152G and the conductive layer 152B are exposed.
  • the organic compound film 103Rf is preferably processed by anisotropic etching.
  • anisotropic dry etching is preferable.
  • wet etching may be used.
  • a gas containing oxygen may be used as the etching gas.
  • oxygen in the etching gas, the etching speed can be increased. Therefore, etching can be performed under low power conditions while maintaining a sufficiently high etching speed. This makes it possible to suppress damage to the organic compound film 103Rf. Furthermore, problems such as adhesion of reaction products that occur during etching can be suppressed.
  • etching gas When dry etching is used, it is preferable to use a gas containing one or more of H2 , CF4 , C4F8 , SF6 , CHF3 , Cl2 , H2O , BCl3 , or a group 18 element such as He or Ar as an etching gas. Alternatively, it is preferable to use a gas containing one or more of these elements and oxygen as an etching gas. Alternatively, oxygen gas may be used as an etching gas.
  • an organic compound film 103Gf that will later become the EL layer 103G is formed.
  • the organic compound film 103Gf can be formed by a method similar to that which can be used to form the organic compound film 103Rf.
  • the organic compound film 103Gf can have the same configuration as the organic compound film 103Rf.
  • a sacrificial film 158Gf and a mask film 159Gf are formed in this order.
  • a resist mask 190G is formed.
  • the material and forming method of the sacrificial film 158Gf and the mask film 159Gf are the same as those applicable to the sacrificial film 158Rf and the mask film 159Rf.
  • the material and forming method of the resist mask 190G are the same as those applicable to the resist mask 190R.
  • the resist mask 190G is placed in a position that overlaps the conductive layer 152G.
  • a portion of the mask film 159Gf is removed using a resist mask 190G to form a mask layer 159G.
  • the mask layer 159G remains on the conductive layer 152G.
  • the resist mask 190G is then removed.
  • a portion of the sacrificial film 158Gf is removed using the mask layer 159G as a mask to form a sacrificial layer 158G.
  • the organic compound film 103Gf is processed to form the EL layer 103G.
  • an organic compound film 103Bf is formed.
  • the organic compound film 103Bf can be formed by a method similar to the method that can be used to form the organic compound film 103Rf.
  • the organic compound film 103Bf can have the same configuration as the organic compound film 103Rf.
  • a sacrificial film 158Bf and a mask film 159Bf are formed in this order.
  • a resist mask 190B is formed.
  • the materials and formation methods of the sacrificial film 158Bf and the mask film 159Bf are the same as those applicable to the sacrificial film 158Rf and the mask film 159Rf.
  • the materials and formation methods of the resist mask 190B are the same as those applicable to the resist mask 190R.
  • the resist mask 190B is placed in a position that overlaps the conductive layer 152B.
  • a resist mask 190B is used to remove a portion of the mask film 159Bf to form a mask layer 159B.
  • the mask layer 159B remains on the conductive layer 152B.
  • the resist mask 190B is then removed.
  • the mask layer 159B is used as a mask to remove a portion of the sacrificial film 158Bf to form a sacrificial layer 158B.
  • the organic compound film 103Bf is processed to form the EL layer 103B.
  • the mask layer 159B and the sacrificial layer 158B are used as hard masks to remove a portion of the organic compound film 103Bf to form the EL layer 103B.
  • a laminated structure of the EL layer 103B, the sacrificial layer 158B, and the mask layer 159B remains on the conductive layer 152B.
  • the mask layers 159R and 159G are exposed.
  • the side surfaces of the EL layers 103R, 103G, and 103B are perpendicular or approximately perpendicular to the surface on which they are formed.
  • the angle between the surface on which they are formed and these side surfaces is 60 degrees or more and 90 degrees or less.
  • the distance between two adjacent ones of the EL layer 103R, EL layer 103G, and EL layer 103B formed by photolithography can be narrowed to 8 ⁇ m or less, 5 ⁇ m or less, 3 ⁇ m or less, 2 ⁇ m or less, or 1 ⁇ m or less.
  • the distance can be defined, for example, as the distance between two adjacent opposing ends of the EL layer 103R, EL layer 103G, and EL layer 103B. In this way, by narrowing the distance between the island-shaped EL layers, a display device having high definition and a large aperture ratio can be provided.
  • the distance between the first electrodes between adjacent light-emitting devices can also be narrowed, for example, to 10 ⁇ m or less, 8 ⁇ m or less, 5 ⁇ m or less, 3 ⁇ m or less, or 2 ⁇ m or less. Note that the distance between the first electrodes between adjacent light-emitting devices is preferably 2 ⁇ m or more and 5 ⁇ m or less.
  • mask layer 159R it is preferable to remove mask layer 159R, mask layer 159G, and mask layer 159B.
  • the mask layer removal process can use the same method as the mask layer processing process.
  • damage to the EL layer 103 during removal of the mask layer can be reduced compared to when a dry etching method is used.
  • the mask layer may also be removed by dissolving it in a polar solvent such as water or alcohol.
  • a polar solvent such as water or alcohol.
  • alcohol include ethyl alcohol, methyl alcohol, isopropyl alcohol (IPA), or glycerin.
  • a drying process may be performed to remove water adsorbed on the surface.
  • a heat treatment can be performed in an inert gas atmosphere or a reduced pressure atmosphere.
  • the heat treatment can be performed at a substrate temperature of 50°C or higher and 200°C or lower, preferably 60°C or higher and 150°C or lower, and more preferably 70°C or higher and 120°C or lower.
  • a reduced pressure atmosphere is preferable because it allows drying at a lower temperature.
  • inorganic insulating film 125f is formed.
  • an insulating film 127f which will later become the insulating layer 127, is formed on the inorganic insulating film 125f.
  • the substrate temperature when forming the inorganic insulating film 125f and the insulating film 127f is preferably 60°C or more, 80°C or more, 100°C or more, or 120°C or more, and 200°C or less, 180°C or less, 160°C or less, 150°C or less, or 140°C or less.
  • the inorganic insulating film 125f it is preferable to form an insulating film having a thickness of 3 nm or more, 5 nm or more, or 10 nm or more, and 200 nm or less, 150 nm or less, 100 nm or less, or 50 nm or less within the above substrate temperature range.
  • the inorganic insulating film 125f is preferably formed, for example, by the ALD method.
  • the ALD method is preferable because it can reduce film formation damage and can form a film with high coverage.
  • As the inorganic insulating film 125f it is preferable to form an aluminum oxide film, for example, by the ALD method.
  • the insulating film 127f is preferably formed using the wet film formation method described above.
  • the insulating film 127f is preferably formed using a photosensitive material, for example, by spin coating, and more specifically, is preferably formed using a photosensitive resin composition containing an acrylic resin.
  • the insulating layer 127 is formed in the area sandwiched between any two of the conductive layers 152R, 152G, and 152B, and around the conductive layer 152C.
  • the width of the insulating layer 127 to be formed later can be controlled by the exposed area of the insulating film 127f.
  • the insulating layer 127 is processed so that it has a portion that overlaps with the upper surface of the conductive layer 151.
  • the light used for exposure preferably contains i-line (wavelength 365 nm).
  • the light used for exposure may also contain at least one of g-line (wavelength 436 nm) and h-line (wavelength 405 nm).
  • an etching process is performed using the insulating layer 127a as a mask to remove a portion of the inorganic insulating film 125f and to thin the thicknesses of the sacrificial layers 158R, 158G, and 158B.
  • the inorganic insulating layer 125 is formed under the insulating layer 127a.
  • the surfaces of the thin portions of the sacrificial layers 158R, 158G, and 158B are exposed.
  • the etching process using the insulating layer 127a as a mask may be referred to as the first etching process.
  • the first etching process can be performed by dry etching or wet etching. Note that if the inorganic insulating film 125f is formed using the same material as the sacrificial layers 158R, 158G, and 158B, the first etching process can be performed in one go, which is preferable.
  • chlorine-based gas When dry etching is performed, it is preferable to use a chlorine-based gas.
  • Cl2 , BCl3 , SiCl4 , CCl4 , etc. can be used alone or in a mixture of two or more gases.
  • oxygen gas, hydrogen gas, helium gas, argon gas, etc. can be appropriately added alone or in a mixture of two or more gases to the chlorine-based gas.
  • a dry etching apparatus having a high-density plasma source can be used.
  • a dry etching apparatus having a high-density plasma source for example, an inductively coupled plasma (ICP) etching apparatus can be used.
  • ICP inductively coupled plasma
  • CCP capacitively coupled plasma
  • the wet etching can be performed using an alkaline solution.
  • TMAH which is an alkaline solution
  • an acid solution containing fluoride can be used. In this case, the wet etching can be performed by the paddle method.
  • the inorganic insulating film 125f is formed using the same material as the sacrificial layer 158R, the sacrificial layer 158G, and the sacrificial layer 158B, the above etching process can be performed at once, which is preferable.
  • the sacrificial layers 158R, 158G, and 158B are not completely removed, and the etching process is stopped when the film thickness becomes thin. In this way, by leaving the corresponding sacrificial layers 158R, 158G, and 158B on the EL layers 103R, 103G, and 103B, it is possible to prevent the EL layers 103R, 103G, and EL layers 103B from being damaged in subsequent processing steps.
  • the entire substrate is exposed to light, and the insulating layer 127a is preferably irradiated with visible light or ultraviolet light.
  • the energy density of the exposure is preferably greater than 0 mJ/ cm2 and equal to or less than 800 mJ/ cm2 , and more preferably greater than 0 mJ/ cm2 and equal to or less than 500 mJ/ cm2 .
  • the transparency of the insulating layer 127a may be improved.
  • the substrate temperature required for a heat treatment to deform the insulating layer 127a into a tapered shape in a later step may be reduced.
  • a barrier insulating layer against oxygen e.g., an aluminum oxide film, etc.
  • oxygen e.g., an aluminum oxide film, etc.
  • a heat treatment (also called post-baking) is performed.
  • the insulating layer 127a can be transformed into an insulating layer 127 having a tapered shape on the side surface (FIG. 9C).
  • the heat treatment is performed at a temperature lower than the heat resistance temperature of the EL layer.
  • the heat treatment can be performed at a substrate temperature of 50° C. or higher and 200° C. or lower, preferably 60° C. or higher and 150° C. or lower, more preferably 70° C. or higher and 130° C. or lower.
  • the heating atmosphere may be an air atmosphere or an inert gas atmosphere.
  • the heating atmosphere may be an atmospheric pressure atmosphere or a reduced pressure atmosphere. This can improve the adhesion between the insulating layer 127 and the inorganic insulating layer 125, and also improve the corrosion resistance of the insulating layer 127.
  • an etching process is performed using the insulating layer 127 as a mask to remove parts of the sacrificial layers 158R, 158G, and 158B.
  • openings are formed in the sacrificial layers 158R, 158G, and 158B, respectively, and the upper surfaces of the EL layers 103R, 103G, 103B, and the conductive layer 152C are exposed.
  • this etching process may be referred to as a second etching process.
  • FIG. 10A shows an example in which a portion of the end of the sacrificial layer 158G (specifically, the tapered portion formed by the first etching process) is covered with the insulating layer 127, and the tapered portion formed by the second etching process is exposed.
  • the second etching process is performed by wet etching.
  • the wet etching method damage to the EL layer 103R, the EL layer 103G, and the EL layer 103B can be reduced compared to the case of using the dry etching method.
  • the wet etching can be performed using, for example, an alkaline solution or an acidic solution. It is preferable to use an aqueous solution so that the EL layer 103 does not dissolve.
  • a common electrode 155 is formed on the EL layer 103R, the EL layer 103G, the EL layer 103B, the conductive layer 152C, and the insulating layer 127.
  • the common electrode 155 can be formed by a method such as sputtering or vacuum deposition.
  • a protective layer 131 is formed on the common electrode 155.
  • the protective layer 131 can be formed by a method such as a vacuum deposition method, a sputtering method, a CVD method, or an ALD method.
  • the substrate 120 is attached onto the protective layer 131 using the resin layer 122, whereby a display device can be manufactured.
  • the insulating layer 156 is provided so as to have an area overlapping with the side surface of the conductive layer 151, and the conductive layer 152 is formed so as to cover the conductive layer 151 and the insulating layer 156. This can increase the yield of the display device and suppress the occurrence of defects.
  • the island-shaped EL layer 103R, the island-shaped EL layer 103G, and the EL layer 103B are formed by forming a film on one surface and then processing it, rather than by using a fine metal mask, so that the island-shaped layers can be formed with a uniform thickness.
  • a high-definition display device or a display device with a high aperture ratio can be realized. Even if the resolution or aperture ratio is high and the distance between the subpixels is extremely short, the EL layer 103R, the EL layer 103G, and the EL layer 103B can be prevented from contacting each other in adjacent subpixels.
  • the occurrence of leakage current between the subpixels can be prevented. This makes it possible to prevent crosstalk and realize a display device with extremely high contrast.
  • the display device has a tandem-type light-emitting device manufactured by a photolithography method, a display device with good characteristics can be provided.
  • the display device of this embodiment can be a high-definition display device. Therefore, the display device of this embodiment can be used, for example, in the display section of a wristwatch-type or bracelet-type information terminal (wearable device), as well as in the display section of a wearable device that can be worn on the head, such as a head-mounted display (HMD) or other VR device, and a glasses-type AR device.
  • a wearable device such as a head-mounted display (HMD) or other VR device, and a glasses-type AR device.
  • HMD head-mounted display
  • AR device glasses-type AR device
  • the display device of this embodiment can be a high-resolution display device or a large display device. Therefore, the display device of this embodiment can be used in electronic devices with relatively large screens, such as television devices, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as in the display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound reproduction devices.
  • electronic devices with relatively large screens such as television devices, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as in the display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and sound reproduction devices.
  • Display module 11A shows a perspective view of a display module 280.
  • the display module 280 has a display device 100A and an FPC 290. Note that the display device included in the display module 280 is not limited to the display device 100A, and may be either a display device 100B or a display device 100E described later.
  • the display module 280 has a substrate 291 and a substrate 292.
  • the display module 280 has a display section 281.
  • the display section 281 is an area that displays an image in the display module 280, and is an area in which light from each pixel provided in a pixel section 284 described later can be viewed.
  • Figure 11B shows a perspective view that shows a schematic configuration on the substrate 291 side.
  • a circuit section 282 On the substrate 291, a circuit section 282, a pixel circuit section 283 on the circuit section 282, and a pixel section 284 on the pixel circuit section 283 are stacked.
  • a terminal section 285 for connecting to an FPC 290 is provided in a portion of the substrate 291 that does not overlap with the pixel section 284.
  • the terminal section 285 and the circuit section 282 are electrically connected by a wiring section 286 that is composed of multiple wirings.
  • the pixel section 284 has a number of pixels 284a arranged periodically. An enlarged view of one pixel 284a is shown on the right side of FIG. 11B.
  • FIG. 11B shows an example in which the pixel 284a has the same configuration as the pixel 178 shown in FIG. 4.
  • the pixel circuit section 283 has a number of pixel circuits 283a arranged periodically.
  • One pixel circuit 283a is a circuit that controls the driving of multiple elements in one pixel 284a.
  • the circuit portion 282 has a circuit that drives each pixel circuit 283a of the pixel circuit portion 283.
  • the circuit portion 282 has one or both of a gate line driver circuit and a source line driver circuit.
  • the circuit portion 282 may have at least one of an arithmetic circuit, a memory circuit, a power supply circuit, etc.
  • the FPC 290 functions as wiring for supplying a video signal, a power supply potential, etc. from the outside to the circuit section 282.
  • an IC may be mounted on the FPC 290.
  • the display module 280 can be configured such that one or both of the pixel circuit section 283 and the circuit section 282 are stacked below the pixel section 284, making it possible to extremely increase the aperture ratio (effective display area ratio) of the display section 281.
  • Such a display module 280 has extremely high resolution and can therefore be suitably used in VR devices such as HMDs or glasses-type AR devices.
  • the display module 280 has an extremely high resolution display unit 281, so that even if the display unit is enlarged with a lens, the pixels are not visible, and a highly immersive display can be achieved.
  • the display module 280 is not limited to this and can be suitably used in electronic devices having a relatively small display unit.
  • the display device 100A shown in FIG. 12A includes a substrate 301, a light-emitting device 130R, a light-emitting device 130G, a light-emitting device 130B, a capacitor 240, and a transistor 310.
  • the substrate 301 corresponds to the substrate 291 in FIG. 11A and FIG. 11B.
  • the transistor 310 is a transistor having a channel formation region in the substrate 301.
  • a semiconductor substrate such as a single crystal silicon substrate can be used as the substrate 301.
  • the transistor 310 has a part of the substrate 301, a conductive layer 311, a low resistance region 312, an insulating layer 313, and an insulating layer 314.
  • the conductive layer 311 functions as a gate electrode.
  • the insulating layer 313 is located between the substrate 301 and the conductive layer 311 and functions as a gate insulating layer.
  • the low resistance region 312 is a region in which the substrate 301 is doped with impurities, and functions as a source or drain.
  • the insulating layer 314 is provided to cover the side surface of the conductive layer 311.
  • an element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301.
  • an insulating layer 261 is provided covering the transistor 310, and a capacitor 240 is provided on the insulating layer 261.
  • Capacitor 240 has conductive layer 241, conductive layer 245, and insulating layer 243 located therebetween. Conductive layer 241 functions as one electrode of capacitor 240, conductive layer 245 functions as the other electrode of capacitor 240, and insulating layer 243 functions as a dielectric of capacitor 240.
  • the conductive layer 241 is provided on the insulating layer 261 and is embedded in the insulating layer 254.
  • the conductive layer 241 is electrically connected to one of the source and drain of the transistor 310 by a plug 271 embedded in the insulating layer 261.
  • the insulating layer 243 is provided to cover the conductive layer 241.
  • the conductive layer 245 is provided in a region that overlaps with the conductive layer 241 via the insulating layer 243.
  • An insulating layer 255 is provided covering the capacitor 240, an insulating layer 174 is provided on the insulating layer 255, and an insulating layer 175 is provided on the insulating layer 174.
  • Light-emitting device 130R, light-emitting device 130G, and light-emitting device 130B are provided on the insulating layer 175.
  • An insulator is provided in the area between adjacent light-emitting devices.
  • Insulating layer 156R is provided so as to have an area overlapping with the side of conductive layer 151R
  • insulating layer 156G is provided so as to have an area overlapping with the side of conductive layer 151G
  • insulating layer 156B is provided so as to have an area overlapping with the side of conductive layer 151B.
  • Conductive layer 152R is provided so as to cover conductive layer 151R and insulating layer 156R
  • conductive layer 152G is provided so as to cover conductive layer 151G and insulating layer 156G
  • conductive layer 152B is provided so as to cover conductive layer 151B and insulating layer 156B.
  • Sacrificial layer 158R is located on EL layer 103R
  • sacrificial layer 158G is located on EL layer 103G
  • sacrificial layer 158B is located on EL layer 103B.
  • the conductive layer 151R, the conductive layer 151G, and the conductive layer 151B are electrically connected to one of the source or drain of the transistor 310 by the insulating layer 243, the insulating layer 255, the insulating layer 174, the plug 256 embedded in the insulating layer 175, the conductive layer 241 embedded in the insulating layer 254, and the plug 271 embedded in the insulating layer 261.
  • Various conductive materials can be used for the plug.
  • a protective layer 131 is provided on the light-emitting devices 130R, 130G, and 130B.
  • the substrate 120 is attached to the protective layer 131 by a resin layer 122.
  • the substrate 120 corresponds to the substrate 292 in FIG. 11A.
  • Figure 12B is a modified example of the display device 100A shown in Figure 12A.
  • the display device shown in Figure 12B has colored layers 132R, 132G, and 132B, and the light-emitting device 130 has an area where it overlaps with one of the colored layers 132R, 132G, and 132B.
  • the light-emitting device 130 can emit, for example, white light.
  • the colored layer 132R can transmit red light
  • the colored layer 132G can transmit green light
  • the colored layer 132B can transmit blue light.
  • FIG. 13 shows a perspective view of the display device 100B
  • FIG. 14 shows a cross-sectional view of the display device 100B.
  • Display device 100B has a configuration in which substrate 352 and substrate 351 are bonded together.
  • substrate 352 is indicated by a dashed line.
  • the display device 100B has a pixel portion 177, a connection portion 140, a circuit 356, wiring 355, and the like.
  • FIG. 13 shows an example in which an IC 354 and an FPC 353 are mounted on the display device 100B. Therefore, the configuration shown in FIG. 13 can also be called a display module having the display device 100B, an IC (integrated circuit), and an FPC.
  • a display device with a connector such as an FPC attached to the substrate, or a display device with an IC mounted on the substrate, is called a display module.
  • connection portion 140 is provided outside the pixel portion 177.
  • the connection portion 140 may be singular or multiple.
  • the connection portion 140 electrically connects the common electrode of the light-emitting device and the conductive layer, and can supply a potential to the common electrode.
  • a scanning line driver circuit can be used as the circuit 356.
  • the wiring 355 has a function of supplying signals and power to the pixel portion 177 and the circuit 356.
  • the signals and power are input to the wiring 355 from the outside via the FPC 353 or from the IC 354.
  • an IC 354 is provided on a substrate 351 by a chip on glass (COG) method or a chip on film (COF) method.
  • COG chip on glass
  • COF chip on film
  • an IC having a scanning line driver circuit or a signal line driver circuit can be used as the IC 354.
  • the display device 100B and the display module may be configured without an IC.
  • the IC may be mounted on an FPC by a COF method, for example.
  • Figure 14 shows an example of a cross section of the display device 100B when a portion of the region including the FPC 353, a portion of the circuit 356, a portion of the pixel portion 177, a portion of the connection portion 140, and a portion of the region including the end portion are cut away.
  • Display device 100C The display device 100C shown in Figure 14 has, between a substrate 351 and a substrate 352, a transistor 201, a transistor 205, a light-emitting device 130R that emits red light, a light-emitting device 130G that emits green light, and a light-emitting device 130B that emits blue light.
  • light-emitting device 130R For details of light-emitting device 130R, light-emitting device 130G, and light-emitting device 130B, refer to embodiments 1 and 2.
  • Light-emitting device 130R has conductive layer 224R, conductive layer 151R on conductive layer 224R, and conductive layer 152R on conductive layer 151R.
  • Light-emitting device 130G has conductive layer 224G, conductive layer 151G on conductive layer 224G, and conductive layer 152G on conductive layer 151G.
  • Light-emitting device 130B has conductive layer 224B, conductive layer 151B on conductive layer 224B, and conductive layer 152B on conductive layer 151B.
  • the conductive layer 224R is connected to the conductive layer 222b of the transistor 205 through an opening provided in the insulating layer 214.
  • the end of the conductive layer 151R is located outside the end of the conductive layer 224R.
  • the insulating layer 156R is provided so as to have an area in contact with the side surface of the conductive layer 151R, and the conductive layer 152R is provided so as to cover the conductive layer 151R and the insulating layer 156R.
  • the conductive layer 224G, conductive layer 151G, conductive layer 152G, and insulating layer 156G in the light-emitting device 130G, and the conductive layer 224B, conductive layer 151B, conductive layer 152B, and insulating layer 156B in the light-emitting device 130B are similar to the conductive layer 224R, conductive layer 151R, conductive layer 152R, and insulating layer 156R in the light-emitting device 130R, so detailed description will be omitted.
  • Conductive layers 224R, 224G, and 224B have recesses formed therein to cover the openings provided in insulating layer 214. Layer 128 is embedded in the recesses.
  • Layer 128 has the function of planarizing the recesses of conductive layer 224R, conductive layer 224G, and conductive layer 224B.
  • Conductive layer 151R, conductive layer 151G, and conductive layer 151B which are electrically connected to conductive layer 224R, conductive layer 224G, and conductive layer 224B, are provided on conductive layer 224R, conductive layer 224G, and conductive layer 224B and layer 128. Therefore, the regions overlapping with the recesses of conductive layer 224R, conductive layer 224G, and conductive layer 224B can also be used as light-emitting regions, and the aperture ratio of the pixel can be increased.
  • Layer 128 may be an insulating layer or a conductive layer.
  • Various inorganic insulating materials, organic insulating materials, and conductive materials can be used as appropriate for layer 128.
  • layer 128 is preferably formed using an insulating material, and is particularly preferably formed using an organic insulating material.
  • the organic insulating material that can be used for the insulating layer 127 described above can be used for layer 128.
  • a protective layer 131 is provided on the light-emitting device 130R, the light-emitting device 130G, and the light-emitting device 130B.
  • the protective layer 131 and the substrate 352 are bonded via an adhesive layer 142.
  • the substrate 352 is provided with a light-shielding layer 157.
  • a solid sealing structure, a hollow sealing structure, or the like can be applied to seal the light-emitting device 130.
  • the space between the substrate 352 and the substrate 351 is filled with the adhesive layer 142, and a solid sealing structure is applied.
  • the space may be filled with an inert gas (nitrogen, argon, etc.) and a hollow sealing structure may be applied.
  • the adhesive layer 142 may be provided so as not to overlap with the light-emitting device.
  • the space may also be filled with a resin different from the adhesive layer 142 provided in a frame shape.
  • connection portion 140 has a conductive layer 224C obtained by processing the same conductive film as the conductive layers 224R, 224G, and 224B, a conductive layer 151C obtained by processing the same conductive film as the conductive layers 151R, 151G, and 151B, and a conductive layer 152C obtained by processing the same conductive film as the conductive layers 152R, 152G, and 152B.
  • an insulating layer 156C is provided so as to have an area overlapping with the side of the conductive layer 151C.
  • the display device 100B is a top emission type. Light emitted by the light emitting device is emitted towards the substrate 352. It is preferable to use a material that is highly transparent to visible light for the substrate 352. If the light emitting device emits infrared or near infrared light, it is preferable to use a material that is highly transparent to the infrared light.
  • the pixel electrode contains a material that reflects visible light
  • the counter electrode (common electrode 155) contains a material that transmits visible light.
  • an insulating layer 211, an insulating layer 213, an insulating layer 215, and an insulating layer 214 are provided in this order.
  • a part of the insulating layer 211 functions as a gate insulating layer for each transistor.
  • a part of the insulating layer 213 functions as a gate insulating layer for each transistor.
  • the insulating layer 215 is provided to cover the transistor.
  • the insulating layer 214 is provided to cover the transistor and functions as a planarizing layer. Note that the number of gate insulating layers and the number of insulating layers covering the transistors are not limited, and each may be a single layer or two or more layers.
  • An organic insulating layer is suitable for the insulating layer 214, which functions as a planarizing layer.
  • Transistor 201 and transistor 205 have a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as a source and a drain, a semiconductor layer 231, an insulating layer 213 that functions as a gate insulating layer, and a conductive layer 223 that functions as a gate.
  • the light-shielding layer 157 can be provided between adjacent light-emitting devices, on the connection portion 140, on the circuit 356, and the like.
  • various optical components can be disposed on the outside of the substrate 352.
  • Substrate 351 and substrate 352 can each be made of a material that can be used for substrate 120.
  • the adhesive layer 142 can be made of a material that can be used for the resin layer 122.
  • connection layer 242 may be an anisotropic conductive film (ACF) or an anisotropic conductive paste (ACP), etc.
  • ACF anisotropic conductive film
  • ACP anisotropic conductive paste
  • Display device 100D The display device 100D shown in FIG. 15 differs from the display device 100C shown in FIG. 14 mainly in that it is a bottom-emission type display device.
  • Light emitted by the light-emitting device is emitted toward the substrate 351. It is preferable to use a material that is highly transparent to visible light for the substrate 351. On the other hand, the translucency of the material used for the substrate 352 does not matter.
  • Figure 15 shows an example in which a light-shielding layer 157 is provided on the substrate 351, an insulating layer 153 is provided on the light-shielding layer, and the transistors 201, 205, etc. are provided on the insulating layer 153.
  • Light-emitting device 130R has conductive layer 112R, conductive layer 126R on conductive layer 112R, and conductive layer 129R on conductive layer 126R.
  • Light-emitting device 130B has conductive layer 112B, conductive layer 126B on conductive layer 112B, and conductive layer 129B on conductive layer 126B.
  • the conductive layers 112R, 112B, 126R, 126B, 129R, and 129B are each made of a material that is highly transparent to visible light. It is preferable to use a material that reflects visible light for the common electrode 155.
  • the light-emitting device 130G is not shown in FIG. 15, the light-emitting device 130G is also provided.
  • Display device 100E The display device 100E shown in FIG. 16 is a modification of the display device 100C shown in FIG. 14, and differs from the display device 100C mainly in that it has colored layers 132R, 132G, and 132B.
  • the light-emitting device 130 has an area that overlaps one of the colored layers 132R, 132G, and 132B.
  • the colored layers 132R, 132G, and 132B can be provided on the surface of the substrate 352 facing the substrate 351.
  • the ends of the colored layers 132R, 132G, and 132B can overlap the light-shielding layer 157.
  • the light-emitting device 130 can emit, for example, white light.
  • the colored layer 132R can transmit red light
  • the colored layer 132G can transmit green light
  • the colored layer 132B can transmit blue light.
  • the display device 100E may be configured such that the colored layers 132R, 132G, and 132B are provided between the protective layer 131 and the adhesive layer 142.
  • Figures 14 and 16 show an example in which the top surface of layer 128 has a flat portion, but the shape of layer 128 is not particularly limited.
  • the electronic device of this embodiment has a display device of one embodiment of the present invention in a display portion.
  • the display device of one embodiment of the present invention has high display performance and can easily achieve high definition and high resolution. Therefore, the display device can be used in the display portion of various electronic devices.
  • Examples of electronic devices include television devices, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, and other electronic devices with relatively large screens, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game machines, personal digital assistants, and audio playback devices.
  • the display device of one embodiment of the present invention can be used favorably in electronic devices having a relatively small display unit, since it is possible to increase the resolution.
  • electronic devices include wristwatch-type and bracelet-type information terminals (wearable devices), as well as wearable devices that can be worn on the head, such as VR devices such as head-mounted displays, glasses-type AR devices, and MR devices.
  • the electronic device of this embodiment may have a sensor (including a function to measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared light).
  • a sensor including a function to measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared light).
  • FIG. 17A to 17D An example of a wearable device that can be worn on the head is described using Figures 17A to 17D.
  • Electronic device 700A shown in FIG. 17A and electronic device 700B shown in FIG. 17B each have a pair of display panels 751, a pair of housings 721, a communication unit (not shown), a pair of mounting units 723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 753, a frame 757, and a pair of nose pads 758.
  • a display device can be applied to the display panel 751. Therefore, the electronic device can be highly reliable.
  • Each of the electronic devices 700A and 700B can project an image displayed on the display panel 751 onto the display area 756 of the optical member 753. Because the optical member 753 is translucent, the user can see the image displayed in the display area superimposed on the transmitted image visible through the optical member 753.
  • Electronic device 700A and electronic device 700B may be provided with a camera capable of capturing an image of the front as an imaging unit. Furthermore, electronic device 700A and electronic device 700B may each be provided with an acceleration sensor such as a gyro sensor, thereby detecting the orientation of the user's head and displaying an image corresponding to that orientation in display area 756.
  • an acceleration sensor such as a gyro sensor
  • the communication unit has a wireless communication device, and can supply, for example, a video signal through the wireless communication device.
  • a connector can be provided to which a cable through which a video signal and a power supply potential can be connected.
  • electronic device 700A and electronic device 700B are provided with batteries, which can be charged wirelessly and/or wired.
  • the housing 721 may be provided with a touch sensor module.
  • touch sensors can be used as the touch sensor module.
  • various types can be used, such as a capacitance type, a resistive film type, an infrared type, an electromagnetic induction type, a surface acoustic wave type, or an optical type.
  • a capacitance type or an optical type sensor it is preferable to use a capacitance type or an optical type sensor in the touch sensor module.
  • Electronic device 800A shown in FIG. 17C and electronic device 800B shown in FIG. 17D each have a pair of display units 820, a housing 821, a communication unit 822, a pair of mounting units 823, a control unit 824, a pair of imaging units 825, and a pair of lenses 832.
  • a display device can be applied to the display portion 820. Therefore, the electronic device can be highly reliable.
  • the display unit 820 is provided inside the housing 821 at a position that can be seen through the lens 832. In addition, by displaying different images on the pair of display units 820, it is also possible to perform three-dimensional display using parallax.
  • electronic device 800A and electronic device 800B each have a mechanism that allows the left-right positions of lens 832 and display unit 820 to be adjusted so that they are optimally positioned according to the position of the user's eyes.
  • the attachment section 823 allows the user to attach the electronic device 800A or electronic device 800B to the head.
  • the imaging unit 825 has a function of acquiring external information.
  • the data acquired by the imaging unit 825 can be output to the display unit 820.
  • An image sensor can be used for the imaging unit 825.
  • multiple cameras may be provided to support multiple angles of view, such as telephoto and wide angle.
  • the electronic device 800A may have a vibration mechanism that functions as a bone conduction earphone.
  • Each of the electronic devices 800A and 800B may have an input terminal.
  • the input terminal can be connected to a cable that supplies a video signal from a video output device or the like, and power for charging a battery provided within the electronic device.
  • the electronic device of one embodiment of the present invention may have a function of wireless communication with the earphone 750.
  • the electronic device may also have an earphone unit.
  • the electronic device 700B shown in FIG. 17B has an earphone unit 727.
  • a portion of the wiring connecting the earphone unit 727 and the control unit may be disposed inside the housing 721 or the attachment unit 723.
  • the electronic device 800B shown in FIG. 17D has an earphone unit 827.
  • the earphone unit 827 and the control unit 824 can be configured to be connected to each other by wire.
  • both glasses-type devices such as electronic device 700A and electronic device 700B
  • goggle-type devices such as electronic device 800A and electronic device 800B
  • the electronic device 6500 shown in FIG. 18A is a portable information terminal that can be used as a smartphone.
  • the electronic device 6500 includes a housing 6501, a display portion 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, a light source 6508, and the like.
  • the display portion 6502 has a touch panel function.
  • a display device can be applied to the display portion 6502. Therefore, the electronic device can be highly reliable.
  • Figure 18B is a schematic cross-sectional view including the end of the housing 6501 on the microphone 6506 side.
  • a transparent protective member 6510 is provided on the display surface side of the housing 6501, and a display panel 6511, optical members 6512, a touch sensor panel 6513, a printed circuit board 6517, a battery 6518, etc. are arranged in the space surrounded by the housing 6501 and the protective member 6510.
  • the display panel 6511, the optical member 6512, and the touch sensor panel 6513 are fixed to the protective member 6510 by an adhesive layer (not shown).
  • a part of the display panel 6511 is folded back, and the FPC 6515 is connected to the folded back part.
  • An IC 6516 is mounted on the FPC 6515.
  • the FPC 6515 is connected to a terminal provided on a printed circuit board 6517.
  • the display device of one embodiment of the present invention can be applied to the display panel 6511. Therefore, an extremely lightweight electronic device can be realized.
  • the display panel 6511 is extremely thin, a large-capacity battery 6518 can be mounted while keeping the thickness of the electronic device small.
  • a connection portion with the FPC 6515 on the back side of the pixel portion, an electronic device with a narrow frame can be realized.
  • FIG 18C shows an example of a television device.
  • a display unit 7000 is built into a housing 7171.
  • the housing 7171 is supported by a stand 7173.
  • a display device can be applied to the display portion 7000. Therefore, the electronic device can be highly reliable.
  • the television device 7100 shown in FIG. 18C can be operated using an operation switch provided on the housing 7171 and a separate remote control 7151.
  • FIG 18D shows an example of a notebook personal computer.
  • the notebook personal computer 7200 has a housing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, and the like.
  • a display unit 7000 is built into the housing 7211.
  • a display device can be applied to the display portion 7000. Therefore, the electronic device can be highly reliable.
  • Figures 18E and 18F show an example of digital signage.
  • the digital signage 7300 shown in FIG. 18E has a housing 7301, a display unit 7000, a speaker 7303, and the like. It can also have LED lamps, operation keys (including a power switch or an operation switch), connection terminals, various sensors, a microphone, and the like.
  • Figure 18F shows a digital signage 7400 attached to a cylindrical pole 7401.
  • the digital signage 7400 has a display unit 7000 that is provided along the curved surface of the pole 7401.
  • a display device of one embodiment of the present invention can be applied to the display portion 7000. Therefore, the electronic device can be highly reliable.
  • the larger the display unit 7000 the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it catches people's attention, which can increase the advertising effectiveness of, for example, advertisements.
  • the digital signage 7300 or the digital signage 7400 can be linked via wireless communication with an information terminal device 7311 or an information terminal device 7411 such as a smartphone carried by a user.
  • the electronic device shown in Figures 19A to 19G has a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), a connection terminal 9006, a sensor 9007 (including a function to measure force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared light), a microphone 9008, etc.
  • the electronic devices shown in Figures 19A to 19G have various functions. For example, they can have a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date or time, etc., a function to control processing by various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc.
  • FIG. 19A is a perspective view showing a mobile information terminal 9171.
  • the mobile information terminal 9171 can be used as a smartphone, for example.
  • the mobile information terminal 9171 may be provided with a speaker 9003, a connection terminal 9006, a sensor 9007, or the like.
  • the mobile information terminal 9171 can display text and image information on multiple surfaces.
  • FIG. 19A shows an example in which three icons 9050 are displayed.
  • Information 9051 shown in a dashed rectangle can also be displayed on another surface of the display unit 9001. Examples of the information 9051 include notifications of incoming e-mail, SNS, telephone calls, etc., the title of e-mail or SNS, the sender's name, the date and time, the remaining battery level, radio wave strength, etc.
  • the icon 9050, etc. may be displayed at the position where the information 9051 is displayed.
  • Figure 19B is an oblique view showing a mobile information terminal 9172.
  • the mobile information terminal 9172 has a function of displaying information on three or more sides of the display unit 9001.
  • information 9052, information 9053, and information 9054 are each displayed on different sides.
  • a user can check information 9053 displayed in a position that can be observed from above the mobile information terminal 9172 while the mobile information terminal 9172 is stored in a breast pocket of a garment.
  • FIG 19C is a perspective view showing a tablet terminal 9173.
  • the tablet terminal 9173 is capable of executing various applications such as mobile phone, e-mail, text viewing and creation, music playback, Internet communication, and computer games, for example.
  • the tablet terminal 9173 has a display unit 9001, a camera 9002, a microphone 9008, and a speaker 9003 on the front side of the housing 9000, operation keys 9005 as operation buttons on the left side of the housing 9000, and a connection terminal 9006 on the bottom.
  • FIG. 19D is a perspective view showing a wristwatch-type mobile information terminal 9200.
  • the mobile information terminal 9200 can be used as, for example, a smart watch (registered trademark).
  • the display surface of the display unit 9001 is curved, and display can be performed along the curved display surface.
  • the mobile information terminal 9200 can also perform hands-free conversation by communicating with, for example, a headset capable of wireless communication.
  • the mobile information terminal 9200 can also perform data transmission with other information terminals and charge itself through the connection terminal 9006. Note that charging may be performed by wireless power supply.
  • FIG. 19E to 19G are perspective views showing a foldable mobile information terminal 9201.
  • FIG. 19E is a perspective view of the mobile information terminal 9201 in an unfolded state
  • FIG. 19G is a perspective view of the mobile information terminal 9201 in a folded state
  • FIG. 19F is a perspective view of the mobile information terminal 9201 in a state in the middle of changing from one of FIG. 19E and FIG. 19G to the other.
  • the mobile information terminal 9201 has excellent portability when folded, and has excellent display visibility due to a seamless wide display area when unfolded.
  • the display unit 9001 of the mobile information terminal 9201 is supported by three housings 9000 connected by hinges 9055.
  • the display unit 9001 can be bent with a radius of curvature of 0.1 mm or more and 150 mm or less.

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  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Spectroscopy & Molecular Physics (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Electroluminescent Light Sources (AREA)
PCT/IB2023/061820 2022-11-30 2023-11-23 発光デバイス Ceased WO2024116031A1 (ja)

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007201407A (ja) * 2005-12-26 2007-08-09 Fuji Xerox Co Ltd 有機電界発光素子
JP2019176093A (ja) * 2018-03-29 2019-10-10 株式会社日本触媒 有機電界発光素子
WO2021045178A1 (ja) * 2019-09-06 2021-03-11 日本放送協会 有機薄膜および有機薄膜の製造方法、有機エレクトロルミネッセンス素子、表示装置、照明装置、有機薄膜太陽電池、光電変換素子、薄膜トランジスタ、塗料組成物、有機エレクトロルミネッセンス素子用材料

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108292714B (zh) 2015-06-29 2020-04-28 Imec 非营利协会 有机层的高分辨率图案化方法

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2007201407A (ja) * 2005-12-26 2007-08-09 Fuji Xerox Co Ltd 有機電界発光素子
JP2019176093A (ja) * 2018-03-29 2019-10-10 株式会社日本触媒 有機電界発光素子
WO2021045178A1 (ja) * 2019-09-06 2021-03-11 日本放送協会 有機薄膜および有機薄膜の製造方法、有機エレクトロルミネッセンス素子、表示装置、照明装置、有機薄膜太陽電池、光電変換素子、薄膜トランジスタ、塗料組成物、有機エレクトロルミネッセンス素子用材料

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