WO2020208474A1 - 発光デバイス、発光装置、発光モジュール、電子機器、及び照明装置 - Google Patents
発光デバイス、発光装置、発光モジュール、電子機器、及び照明装置 Download PDFInfo
- Publication number
- WO2020208474A1 WO2020208474A1 PCT/IB2020/053071 IB2020053071W WO2020208474A1 WO 2020208474 A1 WO2020208474 A1 WO 2020208474A1 IB 2020053071 W IB2020053071 W IB 2020053071W WO 2020208474 A1 WO2020208474 A1 WO 2020208474A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- layer
- light emitting
- emitting device
- compound
- abbreviation
- Prior art date
Links
Images
Classifications
-
- 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
- H10K50/165—Electron transporting layers comprising dopants
-
- 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
- H10K50/125—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers specially adapted for multicolour light emission, e.g. for emitting white light
- H10K50/13—OLEDs or polymer light-emitting diodes [PLED] characterised by the electroluminescent [EL] layers specially adapted for multicolour light emission, e.g. for emitting white light comprising stacked EL layers within one EL unit
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B33/00—Electroluminescent light sources
- H05B33/12—Light sources with substantially two-dimensional radiating surfaces
-
- 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]
- H10K50/14—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]
- H10K50/17—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]
- H10K50/19—Tandem OLEDs
-
- 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
-
- 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
- H10K2101/40—Interrelation of parameters between multiple constituent active layers or sublayers, e.g. HOMO values in adjacent layers
-
- 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
- H10K85/615—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene
- H10K85/626—Polycyclic condensed aromatic hydrocarbons, e.g. anthracene containing more than one polycyclic condensed aromatic rings, e.g. bis-anthracene
Definitions
- One aspect of the present invention relates to a light emitting device (also referred to as a light emitting element), a light emitting device, a light emitting module, an electronic device, and a lighting device.
- a light emitting device also referred to as a light emitting element
- a light emitting device also referred to as a light emitting element
- a light emitting module also referred to as a light emitting module
- an electronic device also referred to as a light emitting element
- One aspect of the present invention is not limited to the above technical fields.
- the technical fields of one aspect of the present invention include semiconductor devices, display devices, light emitting devices, power storage devices, storage devices, electronic devices, lighting devices, input devices (for example, touch sensors), input / output devices (for example, touch panels, etc.). ), Their driving method, or their manufacturing method can be given as an example.
- organic EL devices also referred to as organic EL devices and organic EL elements
- EL organic electroluminescence
- the basic configuration of an organic EL device is such that a layer containing a luminescent organic compound (hereinafter, also referred to as a light emitting layer) is sandwiched between a pair of electrodes. By applying a voltage to this organic EL device, light emission from a luminescent organic compound can be obtained.
- a luminescent organic compound hereinafter, also referred to as a light emitting layer
- the luminescent organic compound examples include a compound that converts a singlet excited state into light emission (also referred to as a fluorescent compound or a fluorescent light emitting substance) and a compound that converts a triplet excited state into light emission (phosphorescent compound, phosphorescent light emission). (Also called a substance).
- Patent Document 1 discloses an organometallic complex having iridium or the like as a central metal as a phosphorescent compound.
- the organic EL device is suitable for a display device because it is easy to be thin and lightweight, can respond to an input signal at high speed, and can be driven by using a DC low voltage power supply.
- the organic EL device can be formed in a film shape, light emission can be obtained in a planar shape. Therefore, a large-area light emitting device can be easily formed. Since this is a feature that is difficult to obtain with a point light source represented by an LED (light emitting diode) and a line light source represented by a fluorescent lamp, the organic EL device has high utility value as a surface light source that can be applied to a lighting device or the like. ..
- One aspect of the present invention is to provide a light emitting device having a long life. Alternatively, one aspect of the present invention is to provide a highly reliable light emitting device. Alternatively, one aspect of the present invention is to provide a light emitting device having a low drive voltage. Alternatively, one aspect of the present invention is to provide a light emitting device having high luminous efficiency.
- the first electrode, the first light emitting layer, the first layer, the second layer, the third layer, the second light emitting layer, and the second electrode are arranged in this order. It is a light emitting device that is laminated and held in.
- the first layer has a first organic compound and a first substance.
- the second layer has a second organic compound.
- the third layer has a second substance.
- the first organic compound is an electron transporting material.
- the first substance is a metal, metal salt, metal oxide, or organometallic salt.
- the second organic compound is an electron transporting material.
- the second substance is an electron injectable material.
- the second layer has a lower concentration of the first substance than the first layer. In particular, the second layer preferably does not contain the first substance.
- the first organic compound and the second organic compound are the same organic compound.
- the third layer preferably further comprises a third organic compound.
- the third organic compound is preferably an electron transporting material.
- the third organic compound is preferably the same organic compound as at least one of the first organic compound and the second organic compound.
- the first substance is preferably an organometallic complex having an alkali metal or an alkaline earth metal.
- the first substance is preferably an organometallic complex having a ligand having nitrogen and oxygen and an alkali metal or an alkaline earth metal.
- the first substance is preferably an organometallic complex having a quinolinol ligand and an alkali metal or alkaline earth metal.
- the second substance preferably has an alkali metal, an alkaline earth metal, or a rare earth metal.
- the first organic compound is HOMO level -6.0eV above, and the electric field intensity electron mobility in the square root 600 [V / cm] is 1 ⁇ 10 -7 cm 2 / Vs or more 5 ⁇ 10 - It is preferably 5 cm 2 / Vs or less.
- the first layer preferably has a first region on the side of the first light emitting layer and a second region on the side of the second light emitting layer. It is preferable that the concentration ratios of the first organic compound and the first substance are different between the first region and the second region. In particular, it is preferable that the concentration of the first substance in the second region is lower than that in the first region.
- the light emitting device of one aspect of the present invention preferably further has a hole injection layer.
- the hole injection layer is preferably located between the first electrode and the first light emitting layer.
- the hole injection layer preferably has a first compound and a second compound.
- the first compound preferably has electron acceptability for the second compound.
- the HOMO level of the second compound is preferably -5.7 eV or more and -5.4 eV or less.
- the light emitting device of one aspect of the present invention preferably further has a first hole transport layer.
- the first hole transport layer is preferably located between the hole injection layer and the first light emitting layer.
- the first hole transport layer preferably has a third compound.
- the HOMO level of the third compound is preferably a value equal to or lower than the HOMO level of the second compound.
- the difference between the HOMO level of the third compound and the HOMO level of the second compound is preferably within 0.2 eV.
- the second compound and the third compound preferably have at least one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton, respectively.
- the light emitting device of one aspect of the present invention preferably further has a second hole transport layer.
- the second hole transport layer is preferably located between the first hole transport layer and the first light emitting layer.
- the second hole transport layer preferably has a fourth compound.
- the HOMO level of the fourth compound is preferably lower than the HOMO level of the third compound.
- the second compound, the third compound, and the fourth compound preferably have at least one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton, respectively.
- the first light emitting layer preferably has a light emitting substance that emits blue light.
- the first light emitting layer preferably has a fluorescent light emitting substance that emits blue light.
- One aspect of the present invention is a light emitting device having a light emitting device having any of the above configurations and one or both of a transistor and a substrate.
- One aspect of the present invention is a module having the above light emitting device and attached with a connector such as a flexible printed circuit board (hereinafter referred to as FPC) or TCP (Tape Carrier Package), or a COG (Chip).
- a connector such as a flexible printed circuit board (hereinafter referred to as FPC) or TCP (Tape Carrier Package), or a COG (Chip).
- FPC flexible printed circuit board
- TCP Tape Carrier Package
- COG Chip
- It is a light emitting module such as a light emitting module in which an integrated circuit (IC) is mounted by an On Glass method or a COF (Chip On Film) method.
- the light emitting module of one aspect of the present invention may have only one of the connector and the IC, or may have both.
- One aspect of the present invention is an electronic device having the above-mentioned light emitting module and at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone, and an operation button.
- One aspect of the present invention is a lighting device having a light emitting device having any of the above configurations and at least one of a housing, a cover, and a support base.
- a long-life light emitting device can be provided.
- one aspect of the present invention can provide a highly reliable light emitting device.
- one aspect of the present invention can provide a light emitting device having a low drive voltage.
- one aspect of the present invention can provide a light emitting device having high luminous efficiency.
- FIGS. 1A to 1D are diagrams showing an example of a light emitting device.
- 2A-2D are diagrams illustrating the concentration of the first substance in the first layer.
- 2E and 2F are diagrams illustrating the concentration of the first substance in the first layer and the second layer.
- FIG. 3A is a top view showing an example of the light emitting device.
- 3B and 3C are cross-sectional views showing an example of a light emitting device.
- 4A to 4D are cross-sectional views showing an example of a light emitting device.
- FIG. 5A is a top view showing an example of the light emitting device.
- FIG. 5B is a cross-sectional view showing an example of a light emitting device.
- 5C and 5D are cross-sectional views showing an example of a transistor.
- FIG. 6A to 6D are diagrams showing an example of an electronic device.
- 7A to 7F are diagrams showing an example of an electronic device.
- 8A to 8C are diagrams showing an example of an electronic device.
- 9A and 9B are diagrams showing the light emitting device of the embodiment.
- FIG. 10 is a diagram showing the luminance-current efficiency characteristics of the light emitting device of the first embodiment.
- FIG. 11 is a diagram showing voltage-current characteristics of the light emitting device of the first embodiment.
- FIG. 12 is a diagram showing an emission spectrum of the light emitting device of Example 1.
- FIG. 13 is a diagram showing the results of the reliability test of the light emitting device of Example 1.
- FIG. 14 is a diagram showing the results of the reliability test of the light emitting device of Example 1.
- FIG. 15 is a diagram showing the luminance-current efficiency characteristics of the light emitting device of the second embodiment.
- FIG. 16 is a diagram showing voltage-current characteristics of the light emitting device of the second embodiment.
- FIG. 17 is a diagram showing an emission spectrum of the light emitting device of Example 2.
- FIG. 18 is a diagram showing the results of the reliability test of the light emitting device of Example 2.
- FIG. 19 is a diagram showing the results of the reliability test of the light emitting device of Example 2.
- membrane and the word “layer” can be interchanged with each other in some cases or depending on the situation.
- conductive layer can be changed to the term “conductive layer”.
- insulating film can be changed to the term “insulating layer”.
- the first electrode, the first light emitting layer, the first layer, the second layer, the third layer, the second light emitting layer, and the second electrode are arranged in this order. It has a stack of.
- the first layer has a first organic compound and a first substance.
- the second layer has a second organic compound.
- the third layer has a second substance.
- the first organic compound and the second organic compound are materials having high electron transport properties (also referred to as electron transport materials), respectively.
- the first substance is a metal, metal salt, metal oxide, or organometallic salt.
- the second substance is a material having high electron injectability (also referred to as an electron injectable material).
- the light emitting device has a configuration in which holes are easily injected into the first light emitting layer and electrons are not easily injected. Holes are easily injected from the first electrode side, and the amount of electrons injected from the second electrode side into the light emitting layer is suppressed, so that it is possible to prevent the light emitting layer from becoming in a state of excess electrons. .. Then, the brightness is increased by injecting electrons into the light emitting layer with the passage of time, and the initial deterioration can be offset by the increase in brightness. Reliability can be improved by using a light emitting device in which initial deterioration is suppressed and the drive life is very long.
- the first layer having the first substance metal, metal salt, metal oxide, or organometallic salt
- the third layer having the second substance electron injectable material
- a second layer is provided between the first layer and the third layer.
- the second layer is a layer having a second organic compound (electron transporting material).
- the second layer is characterized by a lower concentration of the first substance than the first layer.
- the second layer preferably does not contain the first substance. That is, in the present specification and the like, when the concentration of the first substance is lower than that of the first layer, the second layer also includes a structure in which the second layer does not contain the first substance.
- the light emitting device of one aspect of the present invention has a tandem structure in which a plurality of light emitting units are laminated. Specifically, the light emitting device of one aspect of the present invention has at least two light emitting units, a light emitting unit including a first light emitting layer and a light emitting unit including a second light emitting layer.
- the tandem structure light emitting device has higher current efficiency than the single structure light emitting device, and requires less current to illuminate with the same brightness. Therefore, the life of the light emitting device is long, and the reliability can be improved.
- a display device When a display device is manufactured using a light emitting device, a light emitting device having a tandem structure having a common light emitting layer in the sub-pixels of each color is provided, and at least a color filter, a color conversion layer, and a micro optical resonator (microcavity) structure are provided. By combining with one, it is possible to manufacture a display device capable of full-color display.
- the accuracy of arranging the openings of the metal mask at a desired position is highly required.
- a high-definition display device has a high pixel density and requires extremely high alignment accuracy.
- the film is formed in a wider range than a desired region due to the deflection of the metal mask, it is difficult to use it in a large substrate.
- a display device capable of full-color display is produced using the light-emitting device according to one aspect of the present invention, it is not necessary to deposit different light-emitting layers on the sub-pixels of each color. Therefore, a high-definition display device or a large-sized display device can be manufactured with high productivity.
- [Configuration of light emitting device] 1A to 1D show a light emitting device according to an aspect of the present invention.
- the light emitting device shown in FIG. 1A includes a first electrode 1101, a functional layer 1105a, a light emitting layer 1113a, a first layer 1121, a second layer 1122, a third layer 1123, a functional layer 1105b, a light emitting layer 1113b, and a functional layer. It has 1105c and a second electrode 1103.
- a plurality of layers in FIG. 1A, a functional layer 1105a, a light emitting layer 1113a, and a first layer 1121) provided between a pair of electrodes (first electrode 1101 and second electrode 1103) are provided.
- the second layer 1122, the third layer 1123, the functional layer 1105b, the light emitting layer 1113b, and the functional layer 1105c) may be collectively referred to as an EL layer.
- the first electrode 1101 functions as an anode and the second electrode 1103 functions as a cathode will be described as an example.
- the stacking order of the EL layers is reversed.
- the functional layer 1105a, the functional layer 1105b, and the functional layer 1105c include a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a hole block layer, an electron block layer, a charge generation layer, and the like, respectively. At least one layer can be used.
- the light emitting device shown in FIG. 1A is a light emitting device having a tandem structure including a light emitting unit including a light emitting layer 1113a and a light emitting unit including a light emitting layer 1113b. There is a charge generation region between the two light emitting units.
- the charge generation region has a function of injecting electrons into one of the two light emitting units and injecting holes into the other when a voltage is applied to the first electrode 1101 and the second electrode 1103. Therefore, in FIG.
- the light emitting layer 1113a and the light emitting layer 1113b each have a light emitting substance or a plurality of organic compounds in an appropriate combination, and can be configured to obtain fluorescence emission or phosphorescence emission of a desired wavelength.
- the light emitting layer 1113a and the light emitting layer 1113b may be configured to exhibit light of the same color, or may be configured to exhibit light of different colors. The materials that can be used for the light emitting layer will be described later.
- the first layer 1121 has a first organic compound and a first substance.
- the first organic compound is an electron transporting material. Electron-transporting materials have higher electron-transporting properties than holes.
- the first organic compound preferably has a maximum occupied orbital level (HOMO level) of ⁇ 6.0 eV or higher.
- the first organic compound preferably has an electron mobility of 1 ⁇ 10-7 cm 2 / Vs or more and 1 ⁇ 10-5 cm 2 / Vs or less when the square root of the electric field strength [V / cm] is 600. It is more preferably 1 ⁇ 10 -7 cm 2 / Vs or more and 5 ⁇ 10 -5 cm 2 / Vs or less.
- the electron mobility when the square root of the electric field strength [V / cm] of the first organic compound is 600 is smaller than the electron mobility when the square root of the electric field strength [V / cm] of the host material of the light emitting layer 1113a is 600. ..
- the electron transportability of the first layer 1121 By lowering the electron transportability of the first layer 1121, the amount of electrons injected into the light emitting layer 1113a can be controlled, and the light emitting layer 1113a can be prevented from being in a state of excess electrons.
- the first organic compound preferably has an anthracene skeleton, and more preferably has an anthracene skeleton and a heterocyclic skeleton.
- a nitrogen-containing 5-membered ring skeleton is preferable.
- the nitrogen-containing 5-membered ring skeleton it is particularly preferable to have a nitrogen-containing 5-membered ring skeleton containing two complex atoms in the ring, such as a pyrazole ring, an imidazole ring, an oxazole ring, and a thiazole ring.
- Examples of the first organic compound include 2- ⁇ 4- [9,10-di (naphthalen-2-yl) -2-anthril] phenyl ⁇ -1-phenyl-1H-benzoimidazole (abbreviation: ZADN), 9- (1-naphthyl) -10- [4- (2-naphthyl) phenyl] anthracene (abbreviation: ⁇ N- ⁇ NPAnth), 9- [4- (10-phenyl-9-anthracenyl) phenyl] -9H-carbazole ( Abbreviation: CzPA), 7- [4- (10-phenyl-9-anthril) phenyl] -7H-dibenzo [c, g] carbazole (abbreviation: cgDBCzPA) and the like.
- ZADN 9- (1-naphthyl) -10- [4- (2-naphthyl) phen
- an electron transporting material that can be used for a light emitting layer described later an organic compound (host material) that can be used in combination with a fluorescent light emitting substance, and the like can be used.
- the first substance is a metal, metal salt, metal oxide, or organometallic salt.
- the metal examples include alkali metals, alkaline earth metals, and rare earth metals. Specific examples thereof include Li, Na, K, Rb, Cs, Mg, Ca, Sr and Ba.
- the metal salt examples include a halide of the metal and a carbonate of the metal.
- LiF, NaF, KF, RbF, CsF, MgF 2 , CaF 2 , SrF 2 , BaF 2 LiCl, NaCl, KCl, RbCl, CsCl, MgCl 2 , CaCl 2 , SrCl 2 , BaCl 2 , Li.
- Examples thereof include 2 CO 3 and Cs 2 CO 3 .
- metal oxide examples include the oxides of the above metals. Specific examples thereof include Li 2 O, Na 2 O, Cs 2 O, MgO, and CaO.
- organometallic salt examples include an organometallic complex.
- the first substance is preferably an organometallic complex having an alkali metal or an alkaline earth metal.
- the first substance is preferably an organometallic complex having a ligand having nitrogen and oxygen and an alkali metal or an alkaline earth metal.
- the first substance is preferably an organometallic complex having a quinolinol ligand and an alkali metal or alkaline earth metal.
- organic metal complex examples include 8- (quinolinolato) lithium (abbreviation: Liq), 8- (quinolinolato) sodium (abbreviation: Naq), 8- (quinolinolato) potassium (abbreviation: Kq), and (8-quinolinolato) magnesium ( Abbreviation: Mgq 2 ), (8-quinolinolato) zinc (abbreviation: Znq 2 ) and the like can be mentioned.
- Liq is particularly preferable.
- the first layer 1121 may have a first region on the light emitting layer 1113a side and a second region on the light emitting layer 1113b side. It is preferable that the concentration ratios of the first organic compound and the first substance are different between the first region and the second region.
- the second region preferably has a lower concentration of the first substance than the first region.
- the second layer 1122 has a second organic compound.
- the second organic compound is an electron transporting material.
- the material that can be used as the second organic compound is the same as the material that can be used as the first organic compound.
- the first organic compound and the second organic compound may be the same organic compound or different organic compounds.
- the second layer preferably has a lower concentration of the first substance than the first layer.
- the second layer preferably does not contain the first substance.
- the electron injectability from the third layer 1123 to the second layer 1122 and further to the first layer 1121 can be improved. It can be increased and the drive voltage of the light emitting device can be lowered.
- the second substance (or the metal contained in the second substance) may be difficult to diffuse into the first layer 1121.
- the second substance (or the metal contained in the second substance) contained in the third layer 1123 is seconded. It becomes easy to diffuse to the layer 1122 of the above, and the driving voltage of the light emitting device can be lowered. As a result, the reliability of the light emitting device can be improved.
- the third layer 1123 has a second substance.
- the second substance is an electron injectable material.
- an alkali metal, an alkaline earth metal, a rare earth metal, and a compound thereof can be used as the electron-injectable material.
- the alkali metal, alkaline earth metal, and rare earth metal include lithium, cesium, magnesium, calcium, erbium, and ytterbium.
- the compound include alkali metal compounds, alkaline earth metal compounds, and rare earth metal compounds.
- the compound include metal oxides and metal salts. Specific examples thereof include metal oxides such as lithium oxide (Li 2 O) and carbonates such as lithium carbonate (Li 2 CO 3 ) and cesium carbonate (Cs 2 CO 3 ).
- Electride may be used as the electron injectable material. Examples of the electride include a substance in which a high concentration of electrons is added to a mixed oxide of calcium and aluminum.
- the third layer 1123 may further carry a third organic compound. At this time, it is preferable that the second substance exhibits an electron donating property (donor property) with respect to the third organic compound.
- the third organic compound is an electron transporting material.
- the material that can be used as the third organic compound is the same as the material that can be used as the first organic compound.
- the third organic compound and the first organic compound may be the same organic compound or different organic compounds from each other.
- the third organic compound and the second organic compound may be the same organic compound or different organic compounds from each other.
- 1B and 1C are examples of concretely showing the functional layer 1105a, the functional layer 1105b, and the functional layer 1105c in FIG. 1A, respectively.
- the light emitting device shown in FIG. 1B includes a first electrode 1101, a hole injection layer 1111a, a hole transport layer 1112a, a light emitting layer 1113a, a first layer 1121, a second layer 1122, a third layer 1123, and holes. It has an injection layer 1111b, a hole transport layer 1112b, a light emitting layer 1113b, an electron transport layer 1114b, an electron injection layer 1115b, and a second electrode 1103.
- the hole injection layer 1111a preferably has a first compound and a second compound.
- the first compound is an electron acceptor material (acceptor material) and has electron acceptability for the second compound.
- the second compound is a hole transporting material.
- Hole-transporting materials have higher hole-transporting properties than electrons.
- the highest occupied orbital level (HOMO level) of the second compound is preferably relatively low (deep). Specifically, the HOMO level of the second compound is preferably -5.7 eV or more and -5.4 eV or less. The relatively low HOMO level of the second compound facilitates the injection of holes into the hole transport layer 1112a, which is preferable.
- an organic compound having an electron-withdrawing group (particularly a halogen group such as a fluoro group or a cyano group) can be used.
- an organic acceptor such as a quinodimethane derivative, a chloranil derivative, or a hexaazatriphenylene derivative
- a quinodimethane derivative such as a chloranil derivative, or a hexaazatriphenylene derivative
- F 4 -TCNQ 7,7,8,8-(abbreviation: F 4 -TCNQ)
- chloranil 2,3,6,7,10,11 -Hexacyano-1,4,5,8,9,12-Hexaazatriphenylene
- HAT-CN 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane
- F6-TCNNQ 2- (7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyrene-2-ylidene
- a compound such as HAT-CN in which an electron-withdrawing group is bonded to a condensed aromatic ring having a plurality of complex atoms is thermally stable and preferable.
- the [3] radialene derivative having an electron-withdrawing group (particularly a halogen group such as a fluoro group or a cyano group) is preferable because it has very high electron acceptability.
- Examples of the [3] radialene derivative having an electron-withdrawing group include ⁇ , ⁇ ', ⁇ ''-1,2,3-cyclopropanetriylidentris [4-cyano-2,3,5,6-tetrafluoro].
- Benzene acetonitrile ⁇ , ⁇ ', ⁇ ''-1,2,3-cyclopropanetriylidentris [2,6-dichloro-3,5-difluoro-4- (trifluoromethyl) benzene acetonitrile], ⁇ , Examples thereof include ⁇ ', ⁇ ''-1,2,3-cyclopropanetriylidentris [2,3,4,5,6-pentafluorobenzene acetonitrile].
- the second compound preferably has a hole-transporting skeleton.
- a hole transporting skeleton a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton, in which the HOMO level of the hole transporting material does not become too high (shallow), are preferable.
- the second compound preferably has at least one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton and an anthracene skeleton.
- the hole transporting material is an aromatic amine having a substituent containing a dibenzofuran ring or a dibenzothiophene ring, an aromatic monoamine having a naphthalene ring, or an aromatic in which a 9-fluorenyl group is bonded to the nitrogen of the amine via an arylene group. It may be a monoamine.
- the second compound has an N, N-bis (4-biphenyl) amino group because a long-life light emitting device can be produced.
- Examples of the second compound 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- Amin (abbreviation: BBABnf (6)), N, N-bis (4-biphenyl) benzo [b] naphtho [1,2-d] furan-8-amine (abbreviation: BBABnf (8)
- the hole transport layer 1112a shown in FIG. 1B is a layer that transports the holes injected by the hole injection layer 1111a to the light emitting layer 1113a.
- the hole transport layer 1112a preferably has a third compound.
- the third compound is a hole transporting material.
- a hole-transporting material that can be used for the second compound can be used.
- the HOMO level of the third compound is preferably a value equal to or lower than the HOMO level of the second compound.
- the difference between the HOMO level of the third compound and the HOMO level of the second compound is preferably within 0.2 eV.
- the second compound and the third compound preferably have at least one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton, respectively.
- the second compound and the third compound have the same hole-transporting skeleton (particularly a dibenzofuran skeleton) because the hole injection becomes smooth.
- the second compound and the third compound are the same because the injection of holes becomes smooth.
- the hole injection layer 1111b has a function of facilitating injection of holes into the hole transport layer 1112b.
- the hole injection layer 1111b may have the above-mentioned first compound and the second compound. Further, it may have a material having a high hole injection property (hole injection material), which will be described later.
- the hole transport layer 1112b is a layer that transports the holes injected by the hole injection layer 1111b to the light emitting layer 1113b.
- the hole transport layer 1112b preferably has a hole transport material.
- a hole-transporting material that can be used for the second compound can be used. In addition, it may have other hole transporting materials described later.
- the electron transport layer 1114b is a layer that transports the electrons injected by the electron injection layer 1115b to the light emitting layer 1113b.
- the electron transport layer 1114b preferably has an electron transportable material.
- an electron-transporting material that can be used for the first organic compound can be used.
- the electron injection layer 1115b has a function of facilitating injection of electrons into the EL layer.
- the difference between the work function value of the material used for the second electrode 1103 and the lowest empty orbital level (LUMO level) of the material used for the electron injection layer 1115b is preferably small (within 0.5 eV).
- the electron injecting layer 1115b preferably has an electron injecting material.
- an electron-injectable material that can be used for the second substance can be used.
- the light emitting device shown in FIG. 1C has a hole transport layer 1112a having a laminated structure of a hole transport layer 1112a1 and a hole transport layer 1112a2, and a third layer between the third layer 1123 and the hole injection layer 1111b. It differs from the light emitting device shown in FIG. 1B in that it has a layer 1124 of 4 and has a light emitting layer 1113c between the light emitting layer 1113b and the electron transport layer 1114b.
- the hole transport layer 1112a1 and the hole transport layer 1112a2 are layers that transport holes to the light emitting layer 1113a side.
- the hole transport layer 1112a1 preferably has a third compound.
- the third compound is a hole transporting material.
- a hole-transporting material that can be used for the second compound can be used.
- the HOMO level of the third compound is preferably a value equal to or lower than the HOMO level of the second compound.
- the difference between the HOMO level of the third compound and the HOMO level of the second compound is preferably within 0.2 eV.
- the second compound and the third compound are the same because the injection of holes becomes smooth.
- the hole transport layer 1112a1 can have the same configuration as the hole transport layer 1112a in FIG. 1B.
- the hole transport layer 1112a2 preferably has a fourth compound.
- the hole transport layer 1112a2 preferably has a function as an electron block layer.
- the fourth compound is a hole transporting material.
- a hole-transporting material that can be used for the second compound can be used.
- the HOMO level of the fourth compound is preferably lower than the HOMO level of the third compound.
- the difference between the HOMO level of the fourth compound and the HOMO level of the third compound is preferably within 0.2 eV.
- the second compound, the third compound, and the fourth compound preferably have at least one of a carbazole skeleton, a dibenzofuran skeleton, a dibenzothiophene skeleton, and an anthracene skeleton, respectively.
- the second compound, the third compound, and the fourth compound have the same hole transporting skeleton (particularly a dibenzofuran skeleton) because the hole injection becomes smooth.
- the hole transporting materials used for the hole injection layer 1111a, the hole transport layer 1112a1, and the hole transport layer 1112a2 have the above relationship, the hole injection into each layer is smoothly performed and the drive voltage rises. And the state of insufficient holes in the light emitting layer 1113a can be prevented.
- the fourth layer 1124 preferably has an electron transporting material. By providing the fourth layer 1124, the interaction between the third layer 1123 and the hole injection layer 1111b can be suppressed, and electrons can be smoothly transferred.
- the LUMO levels of the electron-transporting material contained in the fourth layer 1124 are the LUMO level of the electron-accepting material contained in the hole injection layer 1111b and the LUMO level of the second substance contained in the third layer 1123. It is preferably between.
- the specific energy level of the LUMO level of the electron transporting material used for the fourth layer 1124 is preferably -5.0 eV or more, more preferably -5.0 eV or more and -3.0 eV or less.
- H 2 Pc Fourth phthalocyanine
- CuPc copper phthalocyanine
- H 2 Pc Fourth phthalocyanine
- phthalocyanine material or metal such as - a metal having an oxygen bond and an aromatic ligand Examples include complexes.
- the light emitting device shown in FIG. 1C has two light emitting units, a light emitting unit having a light emitting layer 1113a and a light emitting unit having a light emitting layer 1113b and a light emitting layer 1113c.
- a light emitting unit having a light emitting layer 1113a For example, by configuring the light emitting layer 1113a to emit blue fluorescence, the light emitting layer 1113b to emit green phosphorescence, and the light emitting layer 1113c to emit red phosphorescence, it is possible to obtain a light emitting device that emits white light as a whole. it can.
- the light emitting device shown in FIG. 1D has a light emitting layer 1113c and a functional layer 1105d between the functional layer 1105c and the second electrode 1103, in addition to the configuration of the light emitting device shown in FIG. 1A.
- the light emitting device has not only two light emitting units.
- the light emitting device shown in FIG. 1D is an example having three light emitting units, a light emitting unit including a light emitting layer 1113a, a light emitting unit including a light emitting layer 1113b, and a light emitting unit including a light emitting layer 1113c.
- the light emitting layer 1113a is configured to emit the first blue light
- the light emitting layer 1113b is configured to emit green, yellow, or yellowish green light and red light
- the light emitting layer 1113c is the second.
- the functional layer 1105c has at least one layer of an electron transport layer, an electron injection layer, a charge generation layer, a hole injection layer, and a hole transport layer.
- the functional layer 1105c has a charge generation region.
- the functional layer 1105d may have, for example, an electron transport layer and an electron injection layer.
- Light emission model in light emitting device A light emitting model in the light emitting device of one aspect of the present invention will be described.
- a light emitting model of the light emitting device will be described using the hole transport layer 1112a, the light emitting layer 1113a, and the first layer 1121 shown in FIG. 1B.
- the light emitting device is not limited to the configuration shown in FIG. 1B, and the light emitting model can be applied to other configurations.
- the light emitting layer 1113a When the light emitting layer 1113a is in a state of excess electrons, a light emitting region is formed in a local region in the light emitting layer 1113a. In other words, the width of the light emitting region in the light emitting layer 1113a is narrow. Therefore, in the local region of the light emitting layer 1113a, the electrons and holes are intensively recombined, and the deterioration is promoted. Further, the electrons that could not be recombined in the light emitting layer 1113a may pass through the light emitting layer 1113a, so that the life or the luminous efficiency may be lowered.
- the width of the light emitting region in the light emitting layer 1113a can be widened by lowering the electron transport property in the first layer 1121.
- the recombination region of electrons and holes in the light emitting layer 1113a can be dispersed. Therefore, it is possible to provide a light emitting device having a long life and good luminous efficiency.
- the light emitting device of one aspect of the present invention may have a maximum value in the deterioration curve of the brightness obtained by the drive test under the condition of constant current density. That is, the light emitting device of one aspect of the present invention may exhibit a behavior in which the brightness increases with the passage of time. This behavior can offset the rapid deterioration at the initial stage of driving (so-called initial deterioration). Therefore, by configuring the light emitting device to exhibit the behavior, the initial deterioration of the light emitting device can be reduced and the drive life can be made very long.
- a light emitting device having a portion where the derivative of the deterioration curve becomes 0 can be rephrased as the light emitting device of one aspect of the present invention.
- the light emitting region may extend to the first layer 1121 side at the initial stage of driving. That is, in the light emitting device of one aspect of the present invention, the light emitting region (that is, the recombination region) is set due to the small hole injection barrier at the initial stage of driving and the relatively low electron transportability of the first layer 1121. It may be formed on the entire light emitting layer 1113a.
- the HOMO level of the first organic compound contained in the first layer 1121 is relatively high at ⁇ 6.0 eV or more, some of the holes reach the first layer 1121 and the first layer Recoupling may also occur in 1121. This phenomenon may also occur when the difference in HOMO level between the host material (or assist material) contained in the light emitting layer 1113a and the first organic compound is within 0.2 eV.
- the carrier balance changes as the driving time elapses, recombination in the first layer 1121 is less likely to occur, and the energy of the recombined carriers effectively contributes to light emission. Can be made to. Therefore, the brightness can be increased as compared with the initial stage of driving. By offsetting the sudden decrease in brightness that appears at the initial stage of driving the light emitting device, that is, the so-called initial deterioration, it is possible to provide a light emitting device having a small initial deterioration and a long driving life.
- the above-mentioned light emitting device may be referred to as a Recombination-Site Tailoring Injection structure (ReSTI structure).
- the first layer 1121 has a portion in which the mixing ratio (concentration) of the first organic compound and the first substance is different in the thickness direction. Specifically, it is preferable to have a portion in which the mixing ratio (concentration) of the electron-transporting material and the organometallic complex of an alkali metal or an alkaline earth metal is different.
- the concentration of the first substance in the first layer 1121 can be inferred from the amount of atoms and molecules detected by time-of-flight secondary ion mass spectrometry (ToF-SIMS: Time-of-flight secondday ion mass spectrometry). ..
- the magnitude of the value detected by ToF-SIMS analysis corresponds to the magnitude of the abundance of the atom or molecule of interest in the portion composed of the same two kinds of materials and having different mixing ratios. Therefore, by comparing the detected amounts of the electron-transporting material and the organometallic complex, it is possible to estimate the magnitude of the mixing ratio.
- the content of the first substance in the first layer 1121 is preferably smaller on the second electrode 1103 side than on the first electrode 1101 side. That is, it is preferable that the first layer 1121 is formed so that the concentration of the first substance increases from the second electrode 1103 side toward the first electrode 1101 side. That is, the first layer 1121 has a portion where the concentration of the first organic compound is lower than the portion where the concentration of the first organic compound is high on the light emitting layer 1113a side. In other words, the first layer 1121 has a portion having a higher concentration of the first substance on the light emitting layer 1113a side than a portion having a lower concentration of the first substance.
- the electron mobility in the portion where the concentration of the first organic compound is high is 1 ⁇ 10 ⁇ when the square root of the electric field strength [V / cm] is 600. It is preferably 7 cm 2 / Vs or more and 5 ⁇ 10 -5 cm 2 / Vs or less.
- the content (concentration) of the first substance in the first layer 1121 can have the configuration shown in FIGS. 2A to 2D.
- FIGS. 2A and 2B show a case where there is no clear boundary in the first layer 1121
- FIGS. 2C and 2D show a case where there is a clear boundary in the first layer 1121.
- the concentrations of the first organic compound and the first substance will each change continuously.
- 2A and 2B show an example in which the concentration of the first substance changes continuously.
- the concentrations of the first organic compound and the first substance change stepwise, respectively.
- 2C and 2D show an example in which the concentration of the first substance changes stepwise.
- the first layer 1121 is composed of a plurality of layers.
- FIG. 2C shows a case where the first layer 1121 has a two-layer laminated structure
- FIG. 2D shows a case where the first layer 1121 has a three-layer laminated structure.
- the broken line represents the boundary region of a plurality of layers.
- the concentration of the first substance is preferably lower in the second layer than in the first layer.
- the content (concentration) of the first substance in the first layer 1121 and the second layer 1122 can be configured as shown in FIGS. 2E and 2F.
- the concentration of the first substance changes stepwise as shown in FIGS. 2E and 2F.
- FIG. 2E shows a case where the first layer 1121 has a single layer structure
- FIG. 2F shows a case where the first layer 1121 has a two-layer laminated structure.
- the change in carrier balance in the light emitting device of one aspect of the present invention is brought about by the change in electron mobility of the first layer 1121 (and the second layer 1122).
- the first layer 1121 has a region where the concentration of the first substance is high and a region where the concentration of the first substance is high between the region where the concentration of the first substance is low and the light emitting layer 1113a. That is, the region having a low concentration of the first substance is located closer to the second electrode 1103 than the region having a high concentration.
- the light emitting device of one aspect of the present invention there is a concentration difference of the first substance between the first layer 1121 and the second layer 1122.
- the light emitting device has a first layer 1121 between the second layer 1122 and the light emitting layer 1113a, which has a higher concentration of the first substance than the second layer 1122. That is, the region having a low concentration of the first substance is located closer to the second electrode 1103 than the region having a high concentration.
- the light emitting device of one aspect of the present invention having the above configuration has a very long life.
- the time until the brightness reaches 95% also referred to as LT95
- LT95 95%
- the materials that can be used for the light emitting device will be described in detail.
- the materials preferably used for the functional layer 1105a (hole injection layer 1111a, hole transport layer 1112a), the first layer 1121, the second layer 1122, the third layer 1123, and the fourth layer 1124 are , Each of which is as described above, but the materials shown below may be used.
- a metal, an alloy, an electrically conductive compound, a mixture thereof, or the like can be appropriately used. Specific examples thereof include In—Sn oxide (also referred to as ITO), In—Si—Sn oxide (also referred to as ITSO), In—Zn oxide, and In—W—Zn oxide.
- ITO In—Sn oxide
- ITSO In—Si—Sn oxide
- Zn oxide In—W—Zn oxide.
- Neodymium (Nd) and other metals, and alloys containing these in appropriate combinations can also be used.
- Other elements belonging to Group 1 or Group 2 of the Periodic Table of Elements not illustrated above eg, lithium (Li), cesium (Cs), calcium (Ca), strontium (Sr)), europium (Eu), ytterbium Rare earth metals such as (Yb) and alloys containing them in appropriate combinations, graphene and the like can be used.
- one of the pair of electrodes of the light emitting device preferably has an electrode having transparency and reflectivity to visible light (semi-transmissive / semi-reflection electrode), and the other has an electrode having reflectivity to visible light (semi-transmissive / semi-reflecting electrode). It is preferable to have a reflective electrode).
- the light emitting device has a microcavity structure, the light emitted from the light emitting layer can be resonated between both electrodes, and the light emitted from the light emitting device can be strengthened.
- the semi-transmissive / semi-reflective electrode may have a laminated structure of an electrode having transparency to visible light (also referred to as a transparent electrode) and a reflective electrode.
- the transmittance of visible light of the transparent electrode shall be 40% or more.
- the reflectance of visible light of the semi-transmissive / semi-reflective electrode is 10% or more and 95% or less, preferably 30% or more and 80% or less.
- the reflectance of visible light of the reflecting electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less.
- the resistivity of the first electrode 1101 and the second electrode 1103 is preferably 1 ⁇ 10 -2 ⁇ cm or less, respectively.
- a sputtering method or a vacuum vapor deposition method can be used for producing the first electrode 1101 and the second electrode 1103.
- the hole injection layer has a function of facilitating injection of holes into the EL layer.
- the hole injection layer can have a function of injecting holes injected from the anode into a hole transport layer (or a light emitting layer or the like).
- the hole injection layer can have a function of generating holes and injecting the holes into a hole transport layer (or a light emitting layer or the like).
- a material having a high hole injecting property (hole injecting material) can be used for the hole injecting layer.
- a composite material containing a material having a high hole transport property (hole transport material) and an electron accepting material can also be used.
- the electron-accepting material extracts electrons from the hole-transporting material to generate holes in the hole-injecting layer, and the holes are injected into the light-emitting layer via the hole-transporting layer.
- the hole injection layer may be formed of a single layer made of a composite material containing a hole transporting material and an electron accepting material, and the hole transporting material and the electron accepting material are separated from each other. It may be formed by laminating with.
- the hole transport layer is a layer that transports holes to the light emitting layer.
- a hole-transporting material can be used for the hole-transporting layer.
- the hole-transporting material used for the hole-transporting layer preferably has a HOMO level that is the same as or close to the HOMO level of the hole-injecting layer.
- Examples of the hole-injectable material include 4,4', 4'-tris (N, N-diphenylamino) triphenylamine (abbreviation: TDATA), 4,4', 4''-tris [N- (3). -Methylphenyl) -N-phenylamino] triphenylamine (abbreviation: MTDATA), 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), 1,3,5-Tris [ N- (4-diphenylaminophenyl) -N-phenylamino] benzene (abbreviation: DPA3B), 3- [N-
- hole-injectable material examples include poly (N-vinylcarbazole) (abbreviation: PVK), poly (4-vinyltriphenylamine) (abbreviation: PVTPA), and poly [N- (4- ⁇ N'-[4- (4-Diphenylamino) phenyl] phenyl-N'-phenylamino ⁇ phenyl) methacrylamide] (abbreviation: PTPDMA), poly [N, N'-bis (4-butylphenyl) -N, N'-bis (phenyl) ) Benzidine] (abbreviation: Poly-TPD) and the like can be used.
- PVK poly (N-vinylcarbazole)
- PVTPA poly (4-vinyltriphenylamine)
- PTPDMA poly [N- (4- ⁇ N'-[4- (4-Diphenylamino) phenyl] phenyl-N'-phenylamino ⁇ phen
- a polymer compound to which an acid such as poly (3,4-ethylenedioxythiophene) / poly (styrene sulfonic acid) (abbreviation: PEDOT / PSS) or polyaniline / poly (styrene sulfonic acid) (Pani / PSS) is added. Etc. can also be used.
- the same material as the material that can be used for the first compound can be used.
- oxides of metals belonging to Group 4 to Group 8 in the Periodic Table of the Elements can also be used. Specific examples thereof include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide and rhenium oxide. Of these, molybdenum oxide is particularly preferable because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle.
- the hole-transporting material used for the hole injection layer and the hole transport layer a substance having a hole mobility of 1 ⁇ 10-6 cm 2 / Vs or more is preferable.
- any substance other than these can be used as long as it is a substance having a higher hole transport property than electrons.
- Examples of the hole transporting material that can be used for the hole injection layer and the hole transporting layer include a hole transporting material that can be used for the second compound.
- the following is a list of other hole-transporting materials that can be used for the hole-injecting layer and the hole-transporting layer (including some overlap with the above).
- a ⁇ -electron-rich heteroaromatic compound for example, a carbazole derivative, a thiophene derivative, a furan derivative, etc.
- an aromatic amine a compound having an aromatic amine skeleton
- Examples of the carbazole derivative (compound having a carbazole skeleton) include a carbazole derivative (for example, a 3,3'-bicarbazole derivative), an aromatic amine having a carbazolyl group, and the like.
- bicarbazole derivative for example, 3,3'-bicarbazole derivative
- PCCP 3,3'-bis (9-phenyl-9H-carbazole)
- 9,9'-bis (1,1'-biphenyl-4-yl) -3,3'-bi-9H-carbazole
- 9,9'-bis (1,1'-biphenyl-3-yl) -3,3'-bi- 9H-carbazole
- 9- (2-naphthyl) -9'-phenyl-9H, 9'H-3,3'-bicarbazole abbreviation: ⁇ NCCP
- aromatic amine having a carbazolyl group examples include PCBA1BP, N- (4-biphenyl) -N- (9,9-dimethyl-9H-fluoren-2-yl) -9-phenyl-9H-carbazole.
- PCBiF -3-Amin
- PCBBiF 4-phenyldiphenyl- (9-phenyl-9H-carbazole-3-yl) amine
- PCA1BP N, N'-bis (abbreviation: PCA1BP) 9-Phenylcarbazole-3-yl) -N, N'-diphenylbenzene-1,3-diamine
- PCA2B N, N', N''-triphenyl-N, N', N''- Tris (9-phenylcarbazole-3-yl) benzene-1,3,5-triamine
- PCA3B 9,9-dimethyl-N-phenyl-N- [4- (9-phenyl-9H-carbazole-) 3-Il) phenyl] Fluoren-2-amine
- PCBAF 4-phenyldiphenyl- (9-phenyl-9H-carbazole-3-yl) amine
- PCA1BP N, N'
- carbazole derivative examples include PCzN2, 3- [4- (9-phenanthryl) -phenyl] -9-phenyl-9H-carbazole (abbreviation: PCPPn), 3- [4- (1-naphthyl)-.
- Phenyl] -9-phenyl-9H-carbazole (abbreviation: PCPN), 1,3-bis (N-carbazolyl) benzene (abbreviation: mCP), 4,4'-di (N-carbazolyl) biphenyl (abbreviation: CBP) , 3,6-bis (3,5-diphenylphenyl) -9-phenylcarbazole (abbreviation: CzTP), 1,3,5-tris [4- (N-carbazolyl) phenyl] benzene (abbreviation: TCPB), 9 -[4- (10-phenyl-9-anthracenyl) phenyl] -9H-carbazole (abbreviation: CzPA) and the like can be mentioned.
- PCPN 1,3-bis (N-carbazolyl) benzene
- CBP 4,4'-di (N-carbazolyl) biphenyl
- thiophene derivative compound having a thiophene skeleton
- furan derivative compound having a furan skeleton
- aromatic amine examples include 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (abbreviation: NPB or ⁇ -NPD) and N, N'-bis (3).
- polymer compounds such as PVK, PVTPA, PTPDMA, and Poly-TPD can also be used.
- the hole transporting material is not limited to the above, and various known materials can be used for the hole injection layer and the hole transport layer in combination of one or a plurality of known materials.
- the light emitting layer is a layer containing a light emitting substance.
- the light emitting layer can have one or more kinds of light emitting substances.
- a substance exhibiting a luminescent color such as blue, purple, bluish purple, green, yellowish green, yellow, orange, and red is appropriately used.
- a substance that emits near infrared light can also be used.
- the light emitting layer may have one or more kinds of organic compounds (host material, assist material, etc.) in addition to the light emitting substance (guest material).
- organic compounds host material, assist material, etc.
- guest material the one or more kinds of organic compounds
- one or both of the hole transporting material and the electron transporting material described in this embodiment can be used.
- a bipolar material may be used as one or more kinds of organic compounds.
- the luminescent material that can be used for the light emitting layer is not particularly limited, and is a luminescent material that converts singlet excitation energy into light emission in the visible light region or near infrared light region, or triplet excitation energy in the visible light region or near infrared region.
- a luminescent substance that changes light emission in the light region can be used.
- Examples of the luminescent substance that converts the single-term excitation energy into luminescence include a substance that emits fluorescence (fluorescent luminescent substance), and examples thereof include pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, and dibenzofuran derivatives. Examples thereof include dibenzoquinoxaline derivatives, quinoxalin derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives and naphthalene derivatives. In particular, the pyrene derivative is preferable because it has a high emission quantum yield.
- pyrene derivative examples include N, N'-bis (3-methylphenyl) -N, N'-bis [3- (9-phenyl-9H-fluoren-9-yl) phenyl] pyrene-1,6. -Diamine (abbreviation: 1,6 mM FLPAPrn), N, N'-diphenyl-N, N'-bis [4- (9-phenyl-9H-fluoren-9-yl) phenyl] pyrene-1,6-diamine (abbreviation) : 1,6FLPAPrn), N, N'-bis (dibenzofuran-2-yl) -N, N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6FrAPrn), N, N'-bis (dibenzothiophene) -2-yl) -N, N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6
- condensed aromatic diamine compounds typified by pyrenediamine compounds such as 1,6FLPAPrn, 1,6 mMFLPAPrn, and 1,6BnfAPrn-03 have high hole trapping properties and are excellent in luminous efficiency and reliability. preferable.
- luminescent substance that converts triplet excitation energy into luminescence examples include a substance that emits phosphorescence (phosphorescent substance) and a substance that exhibits thermally activated delayed fluorescence (Thermally Activated Fluorescence (TADF) material). Can be mentioned.
- Examples of the phosphorescent substance include an organic metal complex having a 4H-triazole skeleton, a 1H-triazole skeleton, an imidazole skeleton, a pyrimidine skeleton, a pyrazine skeleton, or a pyridine skeleton (particularly an iridium complex), and a phenylpyridine derivative having an electron-withdrawing group.
- Examples thereof include an organic metal complex (particularly an iridium complex), a platinum complex, and a rare earth metal complex as a ligand.
- Examples of the phosphorescent substance having a blue or green color and a peak wavelength of the emission spectrum of 450 nm or more and 570 nm or less include the following substances.
- Examples of the phosphorescent substance having a green or yellow color and a peak wavelength of 495 nm or more and 590 nm or less in the emission spectrum include the following substances.
- tris (4-methyl-6-phenylpyrimidinato) iridium (III) (abbreviation: [Ir (mppm) 3 ]
- tris (4-t-butyl-6-phenylpyrimidinato) iridium (III) (abbreviation: [Ir (mppm) 3 ])
- tris (4-t-butyl-6-phenylpyrimidinato) iridium (III) tris (4-t-butyl-6-phenylpyrimidinato) iridium (III).
- Examples of the phosphorescent substance having a yellow or red color and a peak wavelength of 570 nm or more and 750 nm or less in the emission spectrum include the following substances.
- the organic compound (host material, assist material, etc.) used for the light emitting layer one or a plurality of substances having an energy gap larger than the energy gap of the light emitting substance can be selected and used.
- organic compound used in combination with the fluorescent substance it is preferable to use an organic compound having a large energy level in the singlet excited state and a small energy level in the triplet excited state.
- organic compound that can be used in combination with the fluorescent substance examples include condensed polycyclic aromatic compounds such as anthracene derivative, tetracene derivative, phenanthrene derivative, pyrene derivative, chrysene derivative, and dibenzo [g, p] chrysene derivative.
- organic compound used in combination with the fluorescent luminescent material examples include 9-phenyl-3- [4- (10-phenyl-9-anthryl) phenyl] -9H-carbazole (abbreviation: PCzPA), 3,6-diphenyl.
- an organic compound having a larger triplet excitation energy than the triplet excitation energy (energy difference between the base state and the triplet excited state) of the luminescent substance may be selected.
- the plurality of organic compounds are phosphorescent. It is preferable to use it by mixing it with a luminescent substance (particularly an organic metal complex).
- ExTET Extra-Triplet Energy Transfer
- the combination of a plurality of organic compounds is preferably one in which an excitation complex is easily formed, and a compound that easily receives holes (hole transporting material) and a compound that easily receives electrons (electron transporting material) are combined. Is particularly preferred.
- a combination that forms an excitation complex that emits light that overlaps the wavelength of the absorption band on the lowest energy side of the luminescent material, energy transfer becomes smooth and light emission can be obtained efficiently.
- the hole-transporting material and the electron-transporting material the materials shown in the present embodiment can be used. With this configuration, high efficiency, low voltage drive, and long life of the light emitting device can be realized at the same time.
- the HOMO level of the hole-transporting material is equal to or higher than the HOMO level of the electron-transporting material.
- the LUMO level (lowest empty orbital level) of the hole-transporting material is equal to or higher than the LUMO level of the electron-transporting material.
- the LUMO and HOMO levels of the material can be derived from the electrochemical properties (reduction potential and oxidation potential) of the material as measured by cyclic voltammetry (CV) measurements.
- the emission spectrum of the hole transporting material, the emission spectrum of the electron transporting material, and the emission spectrum of the mixed film in which these materials are mixed are compared, and the emission spectrum of the mixed film is the emission spectrum of each material. It can be confirmed by observing the phenomenon of shifting the wavelength longer than the spectrum (or having a new peak on the long wavelength side).
- the transient photoluminescence (PL) of the hole-transporting material, the transient PL of the electron-transporting material, and the transient PL of the mixed membrane in which these materials are mixed are compared, and the transient PL lifetime of the mixed membrane is the transient of each material.
- transient PL may be read as transient electroluminescence (EL). That is, the formation of the excited complex can be confirmed by comparing the transient EL of the hole-transporting material, the transient EL of the electron-transporting material, and the transient EL of the mixed membrane of these, and observing the difference in the transient response. Can be done.
- EL transient electroluminescence
- Organic compounds that can be used in combination with phosphorescent substances include aromatic amines (compounds having an aromatic amine skeleton), carbazole derivatives, dibenzothiophene derivatives (thiophene derivatives), dibenzofuran derivatives (furan derivatives), zinc and aluminum derivatives.
- aromatic amines compounds having an aromatic amine skeleton
- carbazole derivatives dibenzothiophene derivatives (thiophene derivatives)
- dibenzofuran derivatives furan derivatives
- zinc and aluminum derivatives examples thereof include metal complexes, oxadiazole derivatives, triazole derivatives, benzoimidazole derivatives, quinoxalin derivatives, dibenzoquinoxalin derivatives, pyrimidine derivatives, triazine derivatives, pyridine derivatives, bipyridine derivatives, phenanthroline derivatives and the like.
- aromatic amine carbazole derivative, dibenzothiophene derivative, and dibenzofuran derivative, which are organic compounds having high hole transporting properties, include the same specific examples of the hole transporting materials shown above.
- zinc and aluminum-based metal complexes that are organic compounds with high electron transport properties include tris (8-quinolinolato) aluminum (III) (abbreviation: Alq) and tris (4-methyl-8-quinolinolato) aluminum.
- III) abbreviation: Almq 3
- bis (10-hydroxybenzo [h] quinolinato) berylium (II) abbreviation: BeBq 2
- metal complexes having a quinoline skeleton or a benzoquinoline skeleton such as (III) (abbreviation: BAlq) and bis (8-quinolinolato) zinc (II) (abbreviation: Znq).
- oxazoles such as bis [2- (2-benzothazolyl) phenolato] zinc (II) (abbreviation: ZnPBO) and bis [2- (2-benzothiazolyl) phenolato] zinc (II) (abbreviation: ZnBTZ)
- ZnPBO bis [2- (2-benzothazolyl) phenolato] zinc
- ZnBTZ bis [2- (2-benzothiazolyl) phenolato] zinc
- oxadiazole derivative triazole derivative, benzimidazole derivative, quinoxalin derivative, dibenzoquinoxaline derivative, and phenylanthrolin derivative, which are organic compounds having high electron transport properties, are 2- (4-biphenylyl) -5- (4-).
- tert-butylphenyl) -1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis [5- (p-tert-butylphenyl) -1,3,4-oxadiazol-2- Il] Benzene (abbreviation: OXD-7), 9- [4- (5-phenyl-1,3,4-oxadiazol-2-yl) phenyl] -9H-carbazole (abbreviation: CO11), 3-( 4-Biphenylyl) -4-phenyl-5- (4-tert-butylphenyl) -1,2,4-triazol (abbreviation: TAZ), 3- (4-tert-butylphenyl) -4- (4-ethyl) Phenyl) -5- (4-biphenylyl) -1,2,4-triazol (abbreviation: p-EtTAZ), 2- ⁇ 4- [9,10-di (naphthalen
- heterocyclic compound having a diazine skeleton the heterocyclic compound having a triazine skeleton, and the heterocyclic compound having a pyridine skeleton, which are organic compounds having high electron transport properties, are 4,6-bis [3- (phenanthrene-).
- organic compounds having high electron transport properties examples include poly (2,5-pyridinediyl) (abbreviation: PPy) and poly [(9,9-dihexylfluorene-2,7-diyl) -co- (pyridine-3,5). -Diyl)] (abbreviation: PF-Py), poly [(9,9-dioctylfluorene-2,7-diyl) -co- (2,2'-bipyridine-6,6'-diyl)] (abbreviation: Polymer compounds such as PF-BPy) can also be used.
- PPy poly (2,5-pyridinediyl)
- PF-Py poly [(9,9-dihexylfluorene-2,7-diyl) -co- (pyridine-3,5).
- PF-Py poly [(9,9-dioctylfluorene-2,7-di
- the TADF material S 1 level position small difference (singlet energy level of excited state) and T 1 level position and (energy level of a triplet excited state), the triplet excitation energy by reverse intersystem crossing It is a material having a function of converting energy into singlet excitation energy. Therefore, the triplet excited energy can be up-converted to the singlet excited energy by a small amount of heat energy (intersystem crossing), and the singlet excited state can be efficiently generated. In addition, triplet excitation energy can be converted into light emission.
- the conditions for thermally activated delayed fluorescence is efficiently obtained, the energy difference between the S 1 level and T 1 level position is 0eV than 0.2eV or less, preferably not more than 0.1eV than 0eV. Further, the delayed fluorescence in the TADF material refers to light emission having a spectrum similar to that of normal fluorescence but having a remarkably long life. Its life is 10-6 seconds or longer, preferably 10-3 seconds or longer.
- An excited complex that forms an excited state with two types of substances has an extremely small difference between the S 1 level and the T 1 level, and is a TADF material capable of converting triplet excitation energy into singlet excitation energy. Has a function.
- a phosphorescence spectrum observed at a low temperature may be used as an index of the T 1 level.
- the TADF material drawing a tangential line at the short wavelength side of the hem of the fluorescence spectrum, the energy of the wavelength of the extrapolation and S 1 levels, drawing a tangential line at the short wavelength side of the hem of the phosphorescence spectrum, its extrapolation
- the difference between S 1 and T 1 is preferably 0.3 eV or less, and more preferably 0.2 eV or less.
- the TADF material may be used as a guest material or as a host material.
- Examples of the TADF material include fullerenes and derivatives thereof, acridine derivatives such as proflavine, and eosin.
- Examples thereof include metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), palladium (Pd) and the like.
- Examples of the metal-containing porphyrin include protoporphyrin-tin fluoride complex (abbreviation: SnF 2 (Proto IX)), mesoporphyrin-tin fluoride complex (abbreviation: SnF 2 (Meso IX)), and hematoporphyrin-tin fluoride.
- a heterocyclic compound having can be used. Since the heterocyclic compound has a ⁇ -electron-rich heterocyclic ring and a ⁇ -electron-deficient heterocyclic ring, both electron transportability and hole transportability are high, which is preferable.
- an aromatic ring to which an electron-withdrawing group such as a cyano group is bonded may be used.
- a ⁇ -electron-deficient skeleton can be used instead of the ⁇ -electron-deficient heteroaromatic ring.
- a ⁇ -electron-rich backbone can be used instead of the ⁇ -electron-rich heteroaromatic ring.
- the pyridine skeleton, the diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), and triazine skeleton are preferable because they are stable and have good reliability.
- the benzoflopyrimidine skeleton, the benzothienopyrimidine skeleton, the benzoflopyrazine skeleton, and the benzothienopyrazine skeleton are preferable because they have high electron acceptability and good reliability.
- the acridine skeleton, the phenoxazine skeleton, the phenothiazine skeleton, the furan skeleton, the thiophene skeleton, and the pyrrole skeleton are stable and have good reliability. It is preferable to have.
- a dibenzofuran skeleton, a dibenzothiophene 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 preferable.
- a substance in which a ⁇ -electron-rich heteroaromatic ring and a ⁇ -electron-deficient heteroaromatic ring are directly bonded has a stronger donor property of the ⁇ -electron-rich heteroaromatic ring and a stronger acceptability of the ⁇ -electron-deficient heteroaromatic ring. , It is particularly preferable because the energy difference between the singlet excited state and the triplet excited state becomes small.
- an aromatic amine skeleton, a phenazine skeleton, or the like can be used.
- An aromatic ring having a cyano group, a heteroaromatic ring, a carbonyl skeleton such as benzophenone, a phosphine oxide skeleton, a sulfone skeleton and the like can be used.
- a TADF material When a TADF material is used as the luminescent substance, it can also be used in combination with other organic compounds. In particular, it can be combined with the above-mentioned host materials (hole transporting material, electron transporting material).
- S 1 level of the host material is preferably higher than S 1 level of TADF material.
- T 1 level of the host material is preferably higher than the T 1 level of the TADF material.
- the TADF material may be used as the host material and the fluorescent light emitting substance may be used as the guest material.
- the triplet excitation energy generated by the TADF material is converted into singlet excitation energy by the inverse intersystem crossing, and the energy is further transferred to the luminescent material to improve the luminescence efficiency of the luminescent device. be able to.
- the TADF material functions as an energy donor, and the luminescent material functions as an energy acceptor. Therefore, using a TADF material as the host material is very effective when using a fluorescent luminescent material as the guest material.
- S 1 level of TADF material is preferably higher than S 1 level of fluorescence emission substance.
- T 1 level of the TADF material is preferably higher than the S 1 level of the fluorescent substance. Therefore, T 1 level of the TADF material is preferably higher than the T 1 level of the fluorescence substance.
- a TADF material that emits light so as to overlap the wavelength of the absorption band on the lowest energy side of the fluorescent light emitting substance.
- the fluorescent substance preferably has a protecting group around the luminescent group (skeleton that causes light emission) of the fluorescent substance.
- a protecting group a substituent having no ⁇ bond is preferable, a saturated hydrocarbon is preferable, and specifically, an alkyl group having 3 or more and 10 or less carbon atoms, or a substituted or unsubstituted cyclo having 3 or more and 10 carbon atoms or less.
- the luminescent group refers to an atomic group (skeleton) that causes light emission in a fluorescent luminescent substance.
- the luminescent group preferably has a skeleton having a ⁇ bond, preferably contains an aromatic ring, and preferably has a condensed aromatic ring or a condensed heteroaromatic ring.
- the fused aromatic ring or the condensed heteroaromatic ring include a phenanthrene skeleton, a stilbene skeleton, an acridone skeleton, a phenoxazine skeleton, and a phenothiazine skeleton.
- a fluorescent substance having a naphthalene skeleton, anthracene skeleton, fluorene skeleton, chrysene skeleton, triphenylene skeleton, tetracene skeleton, pyrene skeleton, perylene skeleton, coumarin skeleton, quinacridone skeleton, and naphthobisbenzofuran skeleton is preferable because of its high fluorescence quantum yield.
- the electron injection layer has a function of facilitating injection of electrons into the EL layer.
- the electron injection layer can have a function of injecting electrons injected from the cathode into an electron transport layer (or a light emitting layer or the like).
- the electron injection layer can have a function of generating electrons and injecting the electrons into an electron transport layer (or a light emitting layer or the like).
- a material having high electron injectability (electron injectable material) can be used for the electron injection layer.
- a composite material containing a material having a high electron transport property (electron transport material) and an electron donor material (donor material) can also be used.
- electron transport material a material having a high electron transport property
- donor material an electron donor material
- holes are extracted from the electron-transporting material by the electron-donating material, electrons are generated in the electron-transporting layer, and electrons are injected into the light-emitting layer via the electron-transporting layer.
- the electron injection layer may be formed of a single layer made of a composite material containing an electron transporting material and an electron donating material, and the electron transporting material and the electron donating material are laminated in separate layers. May be formed.
- the electron transport layer is a layer that transports electrons to the light emitting layer.
- An electron transporting material can be used for the electron transport layer.
- Examples of the electron-injectable material include materials similar to those that can be used for the second substance.
- the electron donating material used for the electron injecting layer a substance exhibiting electron donating property with respect to the electron transporting material can be used. Specifically, the same material as the material that can be used for the second substance can be mentioned.
- the electron-transporting material used for the electron-injecting layer and the electron-transporting layer is preferably a substance having an electron mobility of 1 ⁇ 10-6 cm 2 / Vs or more.
- any substance other than these can be used as long as it is a substance having a higher electron transport property than holes.
- an electron-transporting material that can be used for the first organic compound can be used.
- a vacuum process such as a vapor deposition method or a solution process such as a spin coating method or an inkjet method can be used to fabricate the light emitting device according to one aspect of the present invention.
- a physical vapor deposition method such as a sputtering method, an ion plating method, an ion beam vapor deposition method, a molecular beam deposition method, or a vacuum vapor deposition method, or a chemical vapor deposition method (CVD method) is used.
- PVD method physical vapor deposition method
- CVD method chemical vapor deposition method
- a vapor deposition method vacuum vapor deposition method, etc.
- a coating method dip coat method, etc.
- printing method in-film deposition method, screen (stencil printing) method, offset (flat plate printing) method, flexo (letter plate printing) method, gravure method, microcontact method Etc.) and so on.
- the material of the functional layer constituting the light emitting device is not limited to the above-mentioned materials.
- a high molecular compound oligoform, dendrimer, polymer, etc.
- a medium molecular compound compound in the intermediate region between low molecular weight and high molecular weight: a molecular weight of 400 or more and 4000 or less
- an inorganic compound quantum dot material, etc.
- a colloidal quantum dot material an alloy type quantum dot material, a core / shell type quantum dot material, a core type quantum dot material, or the like can be used.
- the light emitting device of the present embodiment has a first layer having a first substance (metal, metal salt, metal oxide, or organometallic salt) and a second substance (electron injectable material). ), A second layer having a lower concentration of the first substance than the first layer is provided between the third layer.
- FIG. 3A shows a top view of the light emitting device
- FIGS. 3B and 3C show a cross-sectional view between the alternate long and short dash lines X1-Y1 and X2-Y2 of FIG. 3A.
- the light emitting device shown in FIGS. 3A to 3C can be used for, for example, a lighting device.
- the light emitting device may be any of bottom emission, top emission, and dual emission.
- the light emitting device shown in FIG. 3B includes a substrate 490a, a substrate 490b, a conductive layer 406, a conductive layer 416, an insulating layer 405, an organic EL device 450 (first electrode 401, EL layer 402, and second electrode 403), and It has an adhesive layer 407. It is preferable to apply the configuration of the light emitting device of one aspect of the present invention shown in the first embodiment to the organic EL device 450.
- the organic EL device 450 has a first electrode 401 on the substrate 490a, an EL layer 402 on the first electrode 401, and a second electrode 403 on the EL layer 402.
- the organic EL device 450 is sealed by the substrate 490a, the adhesive layer 407, and the substrate 490b.
- the ends of the first electrode 401, the conductive layer 406, and the conductive layer 416 are covered with the insulating layer 405.
- the conductive layer 406 is electrically connected to the first electrode 401, and the conductive layer 416 is electrically connected to the second electrode 403.
- the conductive layer 406 covered with the insulating layer 405 via the first electrode 401 functions as an auxiliary wiring and is electrically connected to the first electrode 401. It is preferable to have an auxiliary wiring electrically connected to the electrode of the organic EL device 450 because the voltage drop due to the resistance of the electrode can be suppressed.
- the conductive layer 406 may be provided on the first electrode 401. Further, an auxiliary wiring for electrically connecting to the second electrode 403 may be provided on the insulating layer 405 or the like.
- Glass, quartz, ceramic, sapphire, organic resin and the like can be used for the substrate 490a and the substrate 490b, respectively.
- the flexibility of the display device can be increased.
- a light extraction structure for improving the light extraction efficiency, an antistatic film for suppressing the adhesion of dust, a water-repellent film for preventing the adhesion of dirt, and a hardware for suppressing the occurrence of scratches due to use.
- a coat film, a shock absorbing layer, or the like may be arranged.
- Examples of the insulating material that can be used for the insulating layer 405 include resins such as acrylic resin and epoxy resin, and inorganic insulating materials such as silicon oxide, silicon oxide, silicon nitride, silicon nitride, and aluminum oxide.
- various curable adhesives such as a photocurable adhesive such as an ultraviolet curable type, a reaction curable type adhesive, a thermosetting type adhesive, and an anaerobic type adhesive can be used.
- these adhesives include epoxy resin, acrylic resin, silicone resin, phenol resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, EVA (ethylene vinyl acetate) resin and the like.
- a material having low moisture permeability such as epoxy resin is preferable.
- a two-component mixed type resin may be used.
- the light emitting device shown in FIG. 3C has a barrier layer 490c, a conductive layer 406, a conductive layer 416, an insulating layer 405, an organic EL device 450, an adhesive layer 407, a barrier layer 423, and a substrate 490b.
- the barrier layer 490c shown in FIG. 3C has a substrate 420, an adhesive layer 422, and an insulating layer 424 having a high barrier property.
- the organic EL device 450 is arranged between the insulating layer 424 having a high barrier property and the barrier layer 423. Therefore, even if a resin film or the like having a relatively low waterproof property is used for the substrate 420 and the substrate 490b, it is possible to prevent impurities such as water from entering the organic EL device and shortening the life.
- the substrate 420 and the substrate 490b are provided with polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyacrylonitrile resin, acrylic resin, polyimide resin, polymethylmethacrylate resin, and polycarbonate (PC) resin, respectively.
- PET polyethylene terephthalate
- PEN polyethylene naphthalate
- PC polycarbonate
- Polyether sulfone (PES) resin polyamide resin (nylon, aramid, etc.), polysiloxane resin, cycloolefin resin, polystyrene resin, polyamideimide resin, polyurethane resin, polyvinyl chloride resin, polyvinylidene chloride resin, polypropylene resin, polytetra Fluoroethylene (PTFE) resin, ABS resin, cellulose nanofibers and the like can be used.
- glass having a thickness sufficient to have flexibility may be used.
- the insulating layer 424 having a high barrier property it is preferable to use an inorganic insulating film.
- an inorganic insulating film for example, a silicon nitride film, a silicon nitride film, a silicon oxide film, a silicon nitride film, an aluminum oxide film, an aluminum nitride film, or the like can be used. Further, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, a neodymium oxide film and the like may be used. Further, two or more of the above-mentioned insulating films may be laminated and used.
- the barrier layer 423 preferably has at least one inorganic film.
- a single-layer structure of an inorganic film or a laminated structure of an inorganic film and an organic film can be applied to the barrier layer 423.
- the inorganic film the above-mentioned inorganic insulating film is suitable.
- the laminated structure include a structure in which a silicon oxide film, a silicon oxide film, an organic film, a silicon oxide film, and a silicon nitride film are formed in this order.
- the highly barrier insulating layer 424 and the organic EL device 450 can be formed directly on the flexible substrate 420. In this case, the adhesive layer 422 is unnecessary. Further, the insulating layer 424 and the organic EL device 450 can be transferred to the substrate 420 after being formed on the hard substrate via the release layer. For example, the insulating layer 424 and the organic EL device 450 are peeled from the hard substrate by applying heat, force, laser light, or the like to the peeling layer, and then the substrate 420 is bonded using the adhesive layer 422 to bond the substrate 420. It may be transposed to.
- the release layer for example, a laminated structure of an inorganic film containing a tungsten film and a silicon oxide film, an organic resin film such as polyimide, or the like can be used.
- the insulating layer 424 can be formed by applying a high temperature as compared with a resin substrate or the like, so that the insulating layer 424 can be a dense and extremely barrier insulating film.
- FIG. 4A shows a cross-sectional view of the light emitting device.
- the light emitting device shown in FIG. 4A is an active matrix type light emitting device in which a transistor and a light emitting device are electrically connected.
- the light emitting device shown in FIG. 4A includes a substrate 201, a transistor 210, a light emitting device 203R, a light emitting device 203G, a light emitting device 203B, a color filter 206R, a color filter 206G, a color filter 206B, a substrate 205, and the like.
- the transistor 210 is provided on the substrate 201, the insulating layer 202 is provided on the transistor 210, and the light emitting devices 203R, 203G, and 203B are provided on the insulating layer 202.
- the transistor 210 and the light emitting devices 203R, 203G, and 203B are sealed in a space 207 surrounded by the substrate 201, the substrate 205, and the adhesive layer 208.
- Space 207 can be, for example, a decompressed atmosphere, an inert atmosphere, or a resin-filled configuration.
- the light emitting device shown in FIG. 4A has a configuration in which one pixel has a red sub-pixel (R), a green sub-pixel (G), and a blue sub-pixel (B).
- the light emitting device of one aspect of the present invention has a plurality of pixels arranged in a matrix.
- One pixel has one or more sub-pixels.
- One sub-pixel has one light emitting device.
- the pixel has a configuration having three sub-pixels (three colors of R, G, B, or three colors of yellow (Y), cyan (C), and magenta (M), etc.), or a sub-pixel. (4 colors of R, G, B, white (W), 4 colors of R, G, B, Y, etc.) can be applied.
- FIG. 4B shows a detailed configuration of the light emitting device 203R, the light emitting device 203G, and the light emitting device 203B.
- the light emitting devices 203R, 203G, and 203B have a common EL layer 213, and also have a microcavity structure in which the optical distance between the electrodes of each light emitting device is adjusted according to the light emitting color of each light emitting device. It is preferable to apply the configuration of the light emitting device of one aspect of the present invention shown in the first embodiment to each light emitting device.
- the first electrode 211 functions as a reflective electrode
- the second electrode 215 functions as a semi-transmissive / semi-reflective electrode.
- the light emitting device 203R is adjusted so that the optical distance between the first electrode 211 and the second electrode 215 is 220R so that the intensity of red light is enhanced.
- the light emitting device 203G is adjusted so that the optical distance between the first electrode 211 and the second electrode 215 is 220G so that the intensity of green light is enhanced, and the light emitting device 203B is blue.
- the optical distance between the first electrode 211 and the second electrode 215 is adjusted to be 220B so that the light intensity is enhanced.
- the conductive layer 212R is formed on the first electrode 211
- the conductive layer 212G is formed on the first electrode 211 to perform optical adjustment. Can be done.
- a conductive layer having a thickness different from that of the conductive layer 212R and the conductive layer 212G may be formed on the first electrode 211 to adjust the optical distance 220B.
- the ends of the first electrode 211, the conductive layer 212R, and the conductive layer 212G are covered with the insulating layer 204.
- the light emitting device shown in FIG. 4A is a top emission type light emitting device in which light emitted from the light emitting device is emitted through a color filter of each color formed on the substrate 205.
- the color filter can pass a specific wavelength range of visible light and block a specific wavelength range.
- red sub-pixel (R) light emitted from the light emitting device 203R is emitted through the red color filter 206R.
- red light can be obtained from the light emitting device 203R by providing a color filter 206R that allows only the red wavelength region to pass at a position overlapping the light emitting device 203R.
- the light emitted from the light emitting device 203G is emitted through the green color filter 206G
- the blue sub pixel (B) the light emitted from the light emitting device 203B is blue. It is ejected through the color filter 206B.
- a black matrix 209 (which can also be called a black layer) may be provided at the end of one type of color filter. Further, the color filter and the black matrix 209 of each color may be covered with an overcoat layer that transmits visible light.
- the light emitting device shown in FIG. 4C has a configuration in which one pixel has a red sub-pixel (R), a green sub-pixel (G), a blue sub-pixel (B), and a white sub-pixel (W).
- R red sub-pixel
- G green sub-pixel
- B blue sub-pixel
- W white sub-pixel
- the optical distance between the first electrode 211 and the second electrode 215 in the light emitting device 203W may be the same as or different from any of the light emitting devices 203R, 203G, and 203B.
- the optical distance of the light emitting device 203W is set to emit light as shown in FIG. 4C. It is preferable that the optical distance is equal to 220B in the device 203B. As a result, the light obtained from the light emitting device 203W can be brought close to the white light having a desired color temperature.
- FIG. 4A shows a top emission type light emitting device, as shown in FIG. 4D, a light emitting device having a structure (bottom emission type) that extracts light to the substrate 201 side on which the transistor 210 is formed is also one of the present inventions. It is an aspect.
- the transistor 210 is formed on the substrate 201
- the insulating layer 202a is formed on the transistor 210
- the color filters 206R, 206G, and 206B are formed on the insulating layer 202a
- the color filters 206R, 206G, and 206B are formed.
- An example in which the insulating layer 202b is formed and the light emitting devices 203R, 203G, and 203B are formed on the insulating layer 202b is shown.
- a light-shielding substrate and a translucent substrate can be used as the substrate 201, and a translucent substrate can be used as the substrate 205.
- a light-shielding substrate and a translucent substrate can be used as the substrate 205, and a translucent substrate can be used as the substrate 201.
- the light emitting device of one aspect of the present invention can be a passive matrix type or an active matrix type.
- An active matrix type light emitting device will be described with reference to FIG.
- FIG. 5A shows a top view of the light emitting device.
- FIG. 5B shows a cross-sectional view between the alternate long and short dash lines AA'shown in FIG. 5A.
- the active matrix type light emitting device shown in FIGS. 5A and 5B includes a pixel unit 302, a circuit unit 303, a circuit unit 304a, and a circuit unit 304b.
- the circuit unit 303, the circuit unit 304a, and the circuit unit 304b can each function as a scanning line drive circuit (gate driver) or a signal line drive circuit (source driver). Alternatively, it may be a circuit that electrically connects the external gate driver or source driver and the pixel unit 302.
- a routing wiring 307 is provided on the first substrate 301.
- the routing wiring 307 is electrically connected to the FPC 308 which is an external input terminal.
- the FPC 308 transmits an external signal (for example, a video signal, a clock signal, a start signal, a reset signal, etc.) and a potential to the circuit unit 303, the circuit unit 304a, and the circuit unit 304b.
- a printed wiring board may be attached to the FPC 308.
- the configuration shown in FIGS. 5A and 5B can also be said to be a light emitting module having a light emitting device (or light emitting device) and an FPC.
- the pixel unit 302 has a plurality of pixels having an organic EL device 317, a transistor 311 and a transistor 312. It is preferable to apply the configuration of the light emitting device of one aspect of the present invention shown in the first embodiment to the organic EL device 317.
- the transistor 312 is electrically connected to the first electrode 313 of the organic EL device 317.
- the transistor 311 functions as a switching transistor.
- the transistor 312 functions as a current control transistor.
- the number of transistors included in each pixel is not particularly limited, and can be appropriately provided as needed.
- the circuit unit 303 has a plurality of transistors including a transistor 309, a transistor 310, and the like.
- the circuit unit 303 may be formed of a circuit including a unipolar (only one of N-type or P-type) transistors, or may be formed of a CMOS circuit including an N-type transistor and a P-type transistor. Good. Further, it may be configured to have a drive circuit outside.
- the structure of the transistor included in the light emitting device of the present embodiment is not particularly limited.
- a planar type transistor, a stagger type transistor, an inverted stagger type transistor and the like can be used.
- either a top gate type or a bottom gate type transistor structure may be used.
- gates may be provided above and below the semiconductor layer on which the channel is formed.
- the crystallinity of the semiconductor material used for the transistor is also not particularly limited, and either an amorphous semiconductor or a semiconductor having crystallinity (microcrystalline semiconductor, polycrystalline semiconductor, single crystal semiconductor, or semiconductor having a partially crystalline region). May be used. It is preferable to use a semiconductor having crystallinity because deterioration of transistor characteristics can be suppressed.
- the semiconductor layer of the transistor preferably has a metal oxide (also referred to as an oxide semiconductor).
- the semiconductor layer of the transistor may have silicon. Examples of silicon include amorphous silicon and crystalline silicon (low temperature polysilicon, single crystal silicon, etc.).
- the semiconductor layers include, for example, indium and M (M is gallium, aluminum, silicon, boron, ittrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lantern, cerium, neodymium, etc. It is preferable to have one or more selected from hafnium, tantalum, tungsten, and gallium) and zinc.
- M is preferably one or more selected from aluminum, gallium, yttrium, and tin.
- an oxide containing indium (In), gallium (Ga), and zinc (Zn) also referred to as IGZO
- IGZO oxide containing indium (In), gallium (Ga), and zinc (Zn)
- the sputtering target used for forming the In-M-Zn oxide preferably has an In atom ratio of M or more.
- the transistor included in the circuit unit 303, the circuit unit 304a, and the circuit unit 304b and the transistor included in the pixel unit 302 may have the same structure or different structures.
- the structures of the plurality of transistors included in the circuit unit 303, the circuit unit 304a, and the circuit unit 304b may all be the same, or may have two or more types.
- the structures of the plurality of transistors included in the pixel unit 302 may all be the same, or there may be two or more types.
- the end of the first electrode 313 is covered with an insulating layer 314.
- an organic compound such as a negative type photosensitive resin or a positive type photosensitive resin (acrylic resin), or an inorganic compound such as silicon oxide, silicon oxide nitride, or silicon nitride can be used.
- the upper end portion or the lower end portion of the insulating layer 314 has a curved surface having a curvature. Thereby, the covering property of the film formed on the upper layer of the insulating layer 314 can be improved.
- An EL layer 315 is provided on the first electrode 313, and a second electrode 316 is provided on the EL layer 315.
- the EL layer 315 has a light emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer, and the like.
- the plurality of transistors and the plurality of organic EL devices 317 are sealed by the first substrate 301, the second substrate 306, and the sealing material 305.
- the space 318 surrounded by the first substrate 301, the second substrate 306, and the sealing material 305 may be filled with an inert gas (nitrogen, argon, etc.) or an organic substance (including the sealing material 305).
- Epoxy resin or glass frit can be used for the sealing material 305.
- the sealing material 305 is preferably made of a material that does not allow moisture or oxygen to permeate as much as possible.
- a glass frit is used as the sealing material, it is preferable that the first substrate 301 and the second substrate 306 are glass substrates from the viewpoint of adhesiveness.
- 5C and 5D show examples of transistors that can be used in the light emitting device.
- the transistor 320 shown in FIG. 5C is composed of a conductive layer 321 that functions as a gate, an insulating layer 328 that functions as a gate insulating layer, a semiconductor layer 327 having a channel forming region 327i and a pair of low resistance regions 327n, and a pair of low resistance regions 327n.
- the insulating layer 328 is located between the conductive layer 321 and the channel forming region 327i.
- the insulating layer 325 is located between the conductive layer 323 and the channel forming region 327i.
- the transistor 320 is preferably covered with an insulating layer 326.
- the insulating layer 326 may be included in the components of the transistor 320.
- the conductive layer 322a and the conductive layer 322b are each connected to the low resistance region 327n via an opening provided in the insulating layer 324.
- the conductive layer 322a and the conductive layer 322b one functions as a source and the other functions as a drain.
- the insulating layer 325 is provided so as to overlap with at least the channel forming region 327i of the semiconductor layer 327.
- the insulating layer 325 may cover the upper surface and the side surface of the pair of low resistance regions 327n.
- the transistor 330 shown in FIG. 5D functions as a conductive layer 331 that functions as a gate, an insulating layer 338 that functions as a gate insulating layer, a conductive layer 332a and a conductive layer 332b that function as sources and drains, a semiconductor layer 337, and a gate insulating layer. It has an insulating layer 335 and a conductive layer 333 that functions as a gate.
- the insulating layer 338 is located between the conductive layer 331 and the semiconductor layer 337.
- the insulating layer 335 is located between the conductive layer 333 and the semiconductor layer 337.
- the transistor 330 is preferably covered with an insulating layer 334.
- the insulating layer 334 may be included in the components of the transistor 330.
- a configuration in which a semiconductor layer on which a channel is formed is sandwiched between two gates is applied to the transistor 320 and the transistor 330.
- the transistor may be driven by connecting two gates and supplying the same signal to them.
- the threshold voltage of the transistor may be controlled by giving one of the two gates a potential for controlling the threshold voltage and giving the other a potential for driving.
- the insulating layer can function as a barrier layer. With such a configuration, it is possible to effectively suppress the diffusion of impurities from the outside into the transistor, and it is possible to improve the reliability of the light emitting device.
- an inorganic insulating film as the insulating layer 325, the insulating layer 326, the insulating layer 328, the insulating layer 334, the insulating layer 335, and the insulating layer 338, respectively.
- the inorganic insulating film for example, a silicon nitride film, a silicon nitride film, a silicon oxide film, a silicon nitride film, an aluminum oxide film, an aluminum nitride film, or the like can be used.
- a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, a neodymium oxide film and the like may be used. Further, two or more of the above-mentioned insulating films may be laminated and used.
- a metal such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, or tungsten, or a main component thereof.
- examples include alloys.
- a film containing these materials can be used as a single layer or as a laminated structure. For example, a single-layer structure of an aluminum film containing silicon, a two-layer structure in which an aluminum film is laminated on a titanium film, a two-layer structure in which an aluminum film is laminated on a tungsten film, and a copper film on a copper-magnesium-aluminum alloy film.
- Two-layer structure for laminating, two-layer structure for laminating copper film on titanium film, two-layer structure for laminating copper film on tungsten film, titanium film or titanium nitride film, and aluminum film or copper film on top of it A three-layer structure, a molybdenum film or a molybdenum nitride film, on which a titanium film or a titanium nitride film is formed, and an aluminum film or a copper film on which an aluminum film or a copper film is laminated, and then a molybdenum film or There is a three-layer structure for forming a molybdenum nitride film.
- Indium oxide, tin oxide, zinc oxide and other oxides may be used. Further, it is preferable to use copper containing manganese because the controllability of the shape by etching is improved.
- Examples of electronic devices include television devices, monitors for computers, digital cameras, digital video cameras, digital photo frames, mobile phones (also called mobile phones and mobile phone devices), portable game machines, and mobile information terminals. Examples include sound reproduction devices, large game machines such as pachinko machines, biometric authentication devices, and inspection devices.
- the electronic device of one aspect of the present invention has high reliability because the display unit has the light emitting device of one aspect of the present invention.
- a full high-definition image having a resolution of 4K2K, 8K4K, 16K8K, or higher can be displayed.
- the screen size of the display unit can be 20 inches or more diagonally, 30 inches or more diagonally, 50 inches or more diagonally, 60 inches or more diagonally, or 70 inches or more diagonally.
- the electronic device of one aspect of the present invention has flexibility, it can be incorporated along the inner or outer wall of a house or building, or along the curved surface of the interior or exterior of an automobile.
- the electronic device of one aspect of the present invention may have a secondary battery, and it is preferable that the secondary battery can be charged by using non-contact power transmission.
- the secondary battery examples include a lithium ion secondary battery such as a lithium polymer battery (lithium ion polymer battery) using a gel-like electrolyte, a nickel hydrogen battery, a nicad battery, an organic radical battery, a lead storage battery, an air secondary battery, and nickel.
- a lithium ion secondary battery such as a lithium polymer battery (lithium ion polymer battery) using a gel-like electrolyte, a nickel hydrogen battery, a nicad battery, an organic radical battery, a lead storage battery, an air secondary battery, and nickel.
- Examples include zinc batteries and silver-zinc batteries.
- the electronic device of one aspect of the present invention may have an antenna.
- the display unit can display video or information.
- the antenna may be used for non-contact power transmission.
- the electronic device of the present embodiment has sensors (force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, voice, time, hardness, electric field, current, voltage. , Including the ability to measure power, radiation, flow rate, humidity, gradient, vibration, odor or infrared rays).
- the electronic device of the present embodiment can have various functions. For example, a function to display various information (still images, moving images, text images, etc.) on the display unit, a touch panel function, a function to display a calendar, date or time, a function to execute various software (programs), wireless communication. It can have a function, a function of reading a program or data recorded on a recording medium, and the like.
- FIG. 6A shows an example of a television device.
- the display unit 7000 is incorporated in the housing 7101.
- a configuration in which the housing 7101 is supported by the stand 7103 is shown.
- a light emitting device can be applied to the display unit 7000.
- the reliability of the television device 7100 can be improved.
- the operation of the television device 7100 shown in FIG. 6A can be performed by an operation switch included in the housing 7101 or a separate remote control operation machine 7111.
- the display unit 7000 may be provided with a touch sensor, and may be operated by touching the display unit 7000 with a finger or the like.
- the remote controller 7111 may have a display unit that displays information output from the remote controller 7111.
- the channel and volume can be operated by the operation keys or the touch panel included in the remote controller 7111, and the image displayed on the display unit 7000 can be operated.
- the television device 7100 is configured to include a receiver, a modem, and the like.
- the receiver can receive general television broadcasts.
- information communication is performed in one direction (sender to receiver) or two-way (sender and receiver, or between recipients, etc.). It is also possible.
- FIG. 6B 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 incorporated in the housing 7211.
- a light emitting device can be applied to the display unit 7000.
- the reliability of the notebook personal computer 7200 can be improved.
- 6C and 6D show an example of digital signage.
- the digital signage 7300 shown in FIG. 6C has a housing 7301, a display unit 7000, a speaker 7303, and the like. Further, it may have an LED lamp, an operation key (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.
- FIG. 6D is a digital signage 7400 attached to a columnar pillar 7401.
- the digital signage 7400 has a display unit 7000 provided along the curved surface of the pillar 7401.
- the light emitting device of one aspect of the present invention can be applied to the display unit 7000.
- the reliability of the digital signage 7300 and 7400 can be improved.
- the wider the display unit 7000 the more information can be provided at one time. Further, the wider the display unit 7000 is, the more easily it is noticed by people, and for example, the advertising effect of the advertisement can be enhanced.
- the touch panel By applying the touch panel to the display unit 7000, not only the image or moving image can be displayed on the display unit 7000, but also the user can intuitively operate the display unit 7000, which is preferable. In addition, when used for the purpose of providing information such as route information or traffic information, usability can be improved by intuitive operation.
- the digital signage 7300 or the digital signage 7400 can be linked with the information terminal 7311 such as a smartphone or the information terminal 7411 owned by the user by wireless communication.
- the information of the advertisement displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411.
- the display of the display unit 7000 can be switched by operating the information terminal 7311 or the information terminal 7411.
- the digital signage 7300 or the digital signage 7400 can be made to execute a game using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller). As a result, an unspecified number of users can participate in and enjoy the game at the same time.
- FIG. 7A to 7F show an example of a portable information terminal having a flexible display unit 7001.
- the reliability of the portable information terminal can be enhanced.
- the display unit 7001 is manufactured by using the light emitting device of one aspect of the present invention. For example, a light emitting device capable of bending with a radius of curvature of 0.01 mm or more and 150 mm or less can be applied. Further, the display unit 7001 may be provided with a touch sensor, and the portable information terminal can be operated by touching the display unit 7001 with a finger or the like.
- FIG. 7A-7C show an example of a foldable mobile information terminal.
- FIG. 7A shows the unfolded state
- FIG. 7B shows the state in the process of changing from one of the unfolded state or the folded state to the other
- FIG. 7C shows the mobile information terminal 7600 in the folded state.
- the mobile information terminal 7600 is excellent in portability in the folded state, and is excellent in listability due to a wide seamless display area in the unfolded state.
- the display unit 7001 is supported by three housings 7601 connected by a hinge 7602. By bending between the two housings 7601 via the hinge 7602, the mobile information terminal 7600 can be reversibly deformed from the unfolded state to the folded state.
- FIG. 7D and 7E show an example of a foldable mobile information terminal.
- FIG. 7D shows a state in which the display unit 7001 is folded so as to be inside
- FIG. 7E shows a mobile information terminal 7650 in a state in which the display unit 7001 is folded so as to be outside.
- the mobile information terminal 7650 has a display unit 7001 and a non-display unit 7651.
- the display unit 7001 can be folded so as to be inside, so that the display unit 7001 can be prevented from being soiled or damaged.
- FIG. 7F shows an example of a wristwatch-type personal digital assistant.
- the mobile information terminal 7800 has a band 7801, a display unit 7001, an input / output terminal 7802, an operation button 7803, and the like.
- the band 7801 has a function as a housing.
- the portable information terminal 7800 can be equipped with a flexible battery 7805.
- the battery 7805 may be arranged so as to overlap the display unit 7001 or the band 7801, for example.
- the band 7801, the display 7001 and the battery 7805 are flexible. Therefore, it is easy to bend the portable information terminal 7800 into a desired shape.
- the operation button 7803 can have various functions such as power on / off operation, wireless communication on / off operation, manner mode execution / cancellation, and power saving mode execution / cancellation. ..
- the function of the operation button 7803 can be freely set by the operating system incorporated in the mobile information terminal 7800.
- the application can be started by touching the icon 7804 displayed on the display unit 7001 with a finger or the like.
- the personal digital assistant 7800 can execute short-range wireless communication standardized for communication. For example, by communicating with a headset capable of wireless communication, it is possible to make a hands-free call.
- the mobile information terminal 7800 may have an input / output terminal 7802.
- data can be directly exchanged with another information terminal via the connector. It is also possible to charge via the input / output terminal 7802.
- the charging operation of the mobile information terminal illustrated in this embodiment may be performed by non-contact power transmission without going through the input / output terminals.
- FIG. 8A shows the appearance of the automobile 9700.
- FIG. 8B shows the driver's seat of the automobile 9700.
- the automobile 9700 has a vehicle body 9701, wheels 9702, a windshield 9703, a light 9704, a fog lamp 9705 and the like.
- the light emitting device of one aspect of the present invention can be used for a display unit of an automobile 9700 or the like.
- the light emitting devices of one aspect of the present invention can be provided in the display units 9710 to 9715 shown in FIG. 8B.
- the light emitting device of one aspect of the present invention may be used for the light 9704 or the fog lamp 9705.
- the display unit 9710 and the display unit 9711 are display devices provided on the windshield of an automobile.
- the light emitting device of one aspect of the present invention can be in a so-called see-through state in which the opposite side can be seen through by manufacturing the electrodes and wiring with a conductive material having translucency. If the display unit 9710 or the display unit 9711 is in the see-through state, the visibility is not obstructed even when the automobile 9700 is driven. Therefore, the light emitting device of one aspect of the present invention can be installed on the windshield of the automobile 9700.
- a transistor for driving the light emitting device it is preferable to use a transistor having translucency, such as an organic transistor using an organic semiconductor material or a transistor using an oxide semiconductor.
- the display unit 9712 is a display device provided on the pillar portion. For example, by projecting an image from an imaging means provided on the vehicle body on the display unit 9712, the field of view blocked by the pillars can be complemented.
- the display unit 9713 is a display device provided on the dashboard portion.
- the field of view blocked by the dashboard can be complemented by displaying the image from the imaging means provided on the vehicle body on the display unit 9713. That is, by projecting an image from an imaging means provided on the outside of the automobile, the blind spot can be supplemented and the safety can be enhanced. In addition, by projecting an image that complements the invisible part, safety confirmation can be performed more naturally and without discomfort.
- FIG. 8C shows the interior of an automobile in which bench seats are used for the driver's seat and the passenger's seat.
- the display unit 9721 is a display device provided on the door unit.
- the field of view blocked by the door can be complemented by displaying the image from the imaging means provided on the vehicle body on the display unit 9721.
- the display unit 9722 is a display device provided on the handle.
- the display unit 9723 is a display device provided at the center of the seating surface of the bench seat. It is also possible to install the display device on the seat surface or the backrest portion, and use the display device as a seat heater using the heat generated by the display device as a heat source.
- the display unit 9714, the display unit 9715, or the display unit 9722 can provide various information by displaying navigation information, a speedometer, a tachometer, a mileage, a fuel gauge, a gear status, an air conditioning setting, and the like. ..
- the display items and layout displayed on the display unit can be appropriately changed according to the preference of the user.
- the above information can also be displayed on the display units 9710 to 9713, the display unit 9721, and the display unit 9723.
- the display units 9710 to 9715 and the display units 9721 to 9723 can be used as lighting devices.
- the display units 9710 to 9715 and the display units 9721 to 9723 can be used as a heating device.
- the results of producing and evaluating the device 1 and the device 2 to which one aspect of the present invention is applied and the comparison device 3 for comparison as the light emitting device will be described.
- the structures of the device 1, the device 2, and the comparison device 3 used in this embodiment are shown in FIG. 9A, and the specific configuration is shown in Table 1.
- the chemical formulas of the materials used in this example are shown below.
- the first electrode 801 is formed on the substrate 800, and the hole injection layer 811a is formed on the first electrode 801.
- Hole transport layer 812a1, hole transport layer 812a2, light emitting layer 813a, first layer 821, second layer 822, third layer 823, fourth layer 824, hole injection layer 811b, hole transport layer 812b, light emitting layer 813b1, light emitting layer 813b2, light emitting layer 813b3, electron transport layer 814b1, electron transport layer 814b2, and electron injection layer 815b are sequentially laminated, and a second electrode 803 is formed on the electron injection layer 815b.
- microcavity structure having a structure for intensifying blue light was applied.
- the first electrode 801 was formed on the substrate 800.
- the electrode area was 4 mm 2 (2 mm ⁇ 2 mm).
- a glass substrate was used as the substrate 800.
- the first electrode 801 is formed by forming an alloy of silver (Ag), palladium (Pd) and copper (Cu) (Ag-Pd-Cu (APC)) so as to have a film thickness of 100 nm by a sputtering method, and oxidizing the first electrode 801. It was formed by forming a film of indium tin oxide (ITSO) containing silicon so as to have a film thickness of 10 nm by a sputtering method.
- the first electrode 801 functions as an anode.
- the surface of the substrate was washed with water, fired at 200 ° C. for 1 hour, and then UV ozone treatment was performed for 370 seconds.
- the substrate was introduced into a vacuum vapor deposition apparatus whose internal pressure was reduced to about 10-4 Pa, vacuum fired at 170 ° C. for 30 minutes in a heating chamber inside the vacuum vapor deposition apparatus, and then the substrate was released for about 30 minutes. It was chilled.
- the hole injection layer 811a was formed on the first electrode 801.
- the hole injection layer 811a is formed by depressurizing the inside of the vacuum deposition apparatus to 10 -4 Pa, and then N, N-bis (4-biphenyl) -6-phenylbenzo [b] naphtho [1,2-d] furan-8.
- -Amine abbreviation: BBABnf
- ALD-MP001Q Analysis Studio Co., Ltd., material serial number: 1S20180314
- the hole transport layer 812a1 was formed on the hole injection layer 811a.
- the hole transport layer 812a1 was formed by vapor deposition using BBABnf so that the film thickness was 10 nm.
- the hole transport layer 812a2 was formed on the hole transport layer 812a1.
- the hole transport layer 812a2 is vapor-deposited to a film thickness of 10 nm using 3,3'-(naphthalene-1,4-diyl) bis (9-phenyl-9H-carbazole) (abbreviation: PCzN2). Formed.
- a light emitting layer 813a was formed on the hole transport layer 812a2.
- the light emitting layer 813a uses 9- (1-naphthyl) -10- [4- (2-naphthyl) phenyl] anthracene (abbreviation: ⁇ N- ⁇ NPAnth) as a host material, and 3 as a guest material (fluorescent light emitting substance).
- a first layer 821 was formed on the light emitting layer 813a.
- the first layer 821 in the device 1 and the device 2 is 2- ⁇ 4- [9,10-di (naphthalene-2-yl) -2-anthryl] phenyl ⁇ -1-phenyl-1H-benzimidazole (abbreviation: abbreviation:).
- ZADN 2- ⁇ 4- [9,10-di (naphthalene-2-yl) -2-anthryl] phenyl ⁇ -1-phenyl-1H-benzimidazole
- ZADN 8- (quinolinolato) lithium
- Liq quinolinolato lithium
- a second layer 822 was formed on the first layer 821.
- the second layer 822 in the device 1 uses ZADN, and the second layer 822 in the device 2 is 2,9-bis (naphthalene-2-yl) -4,7-diphenyl-1,10-phenanthroline (abbreviation). : NBphenyl) was used, and each was formed by vapor deposition so that the film thickness was 5 nm. In the comparison device 3, the second layer 822 was not provided.
- a third layer 823 was formed on the second layer 822 (or on the first layer 821).
- the third layer 823 was formed by vapor deposition using lithium oxide (Li 2 O) so as to have a film thickness of 0.1 nm.
- the fourth layer 824 was formed by vapor deposition using copper phthalocyanine (CuPc) so as to have a film thickness of 2 nm.
- CuPc copper phthalocyanine
- the hole transport layer 812b was formed on the hole injection layer 811b.
- the hole transport layer 812b is composed of N- (1,1'-biphenyl-4-yl) -N- [4- (9-phenyl-9H-carbazole-3-yl) phenyl] -9,9-dimethyl-9H. It was formed by vapor deposition using ⁇ fluorene-2-amine (abbreviation: PCBBiF) so as to have a film thickness of 15 nm.
- PCBBiF ⁇ fluorene-2-amine
- a light emitting layer 813b1 was formed on the hole transport layer 812b.
- the light emitting layer 813b1 uses 2- [3'-(dibenzothiophen-4-yl) biphenyl-3-yl] dibenzo [f, h] quinoxaline (abbreviation: 2mDBTBPDBq-II) as a host material, and uses it as an assist material.
- a light emitting layer 813b2 was formed on the light emitting layer 813b1.
- the light emitting layer 813b2 uses 2mDBTBPDBq-II as a host material, PCBBiF as an assist material, and tris (4-t-butyl-6-phenylpyrimidinato) iridium (III) as a guest material (phosphorescent substance).
- the light emitting layer 813b3 was formed on the light emitting layer 813b2.
- the light emitting layer 813b3 was formed so as to have a film thickness of 5 nm by using the same material and weight ratio as the light emitting layer 813b1.
- an electron transport layer 814b1 was formed on the light emitting layer 813b3.
- the electron transport layer 814b1 was formed by vapor deposition using 2mDBTBPDBq-II so that the film thickness was 10 nm.
- the electron transport layer 814b2 was formed on the electron transport layer 814b1.
- the electron transport layer 814b2 was formed by vapor deposition using NBphen so that the film thickness was 15 nm.
- an electron injection layer 815b was formed on the electron transport layer 814b2.
- the electron injection layer 815b was formed by vapor deposition using lithium fluoride (LiF) so as to have a film thickness of 1 nm.
- a second electrode 803 was formed on the electron injection layer 815b.
- the product (ITO) was formed by forming a film with a thickness of 70 nm by a sputtering method.
- the second electrode 803 functions as a cathode.
- a light emitting device formed by sandwiching an EL layer between a pair of electrodes is formed on the substrate 800.
- the hole injection layer, the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the first to fourth layers described in the above steps constitute the EL layer according to one aspect of the present invention. It is a functional layer. Further, in all the vapor deposition steps in the above-mentioned production method, the vapor deposition method by the resistance heating method was used.
- the light emitting device manufactured as shown above is sealed by another substrate (not shown).
- another substrate (not shown) coated with an adhesive that is solidified by ultraviolet light is placed on the substrate 800 in a glove box having a nitrogen atmosphere.
- the substrates were fixed and the substrates were adhered to each other so that the adhesive adhered around the light emitting device formed on the substrate 800.
- the adhesive was stabilized by irradiating it with ultraviolet light of 365 nm at 6 J / cm 2 to solidify the adhesive and heat-treating it at 80 ° C. for 1 hour.
- ⁇ Operating characteristics of light emitting device ⁇ The operating characteristics of device 1, device 2, and comparison device 3 were measured. The measurement was performed at room temperature (atmosphere maintained at 25 ° C.).
- FIG. 10 shows the luminance-current efficiency characteristics of each light emitting device.
- FIG. 11 shows the voltage-current characteristics of each light emitting device.
- Table 2 shows the main initial characteristic values of each light emitting device at around 1000 cd / m 2 .
- each light emitting device was found to have high luminous efficiency. As shown in FIG. 11, it was found that the device 1 and the device 2 had better voltage-current characteristics than the comparison device 3.
- FIG. 12 shows an emission spectrum when a current is passed through each light emitting device at a current density of 2.5 mA / cm 2 .
- each light emitting device has a microcavity structure that enhances blue light.
- each light emitting device showed an emission spectrum having a maximum peak near 451 nm.
- FIGS. 13 and 14 The results of the reliability test are shown in FIGS. 13 and 14.
- the vertical axis represents the normalized luminance (%) when the initial luminance is 100%
- the horizontal axis represents the driving time (h).
- the vertical axis shows the voltage change ( ⁇ V) when the initial voltage is 0, and the horizontal axis shows the drive time (h).
- the current density was set to 50 mA / cm 2 and each light emitting device was driven.
- the LT90 of the device 1 (the time when the brightness decreases to 90% of the initial brightness) was 95 hours, and the LT90 of the device 2 was 112 hours.
- the LT90 of the comparison device 3 was 64 hours.
- the device 1 and the device 2 have a smaller long-term change in voltage and are less likely to increase in voltage than the comparative device 3.
- Device 1 and Device 2 comprises a first layer 821 containing Liq
- the third layer 823 is a Li 2 O film, during, in that it has a second layer 822 containing no Liq, comparison device Different from 3.
- the configuration in which the second layer 822 is provided between the first layer 821 and the third layer 823 is a light emitting device. It turned out that the reliability of.
- the same organic compound as the first layer 821 (ZADN in this example) may be used for the second layer 822, and different organic compounds (in this example) may be used. It was found that NBphen) may be used.
- ⁇ Operating characteristics of light emitting device ⁇ The operating characteristics of the device 4 and the comparison device 5 were measured. The measurement was performed at room temperature (atmosphere maintained at 25 ° C.).
- FIG. 15 shows the luminance-current efficiency characteristics of each light emitting device.
- FIG. 16 shows the voltage-current characteristics of each light emitting device.
- Table 4 shows the main initial characteristic values of each light emitting device at around 1000 cd / m 2 .
- the device 4 had better luminance-current efficiency characteristics and voltage-current characteristics than the comparative device 5.
- FIG. 17 shows an emission spectrum when a current is passed through each light emitting device at a current density of 12.5 mA / cm 2 .
- Each light emitting device of this embodiment has a tandem structure in which two light emitting units that emit blue light are laminated.
- Each light emitting device contains 3,10-bis [N- (9-phenyl-9H-carbazole-2-yl) -N-phenylamino] naphtho [2,3-b; 6] contained in the light emitting layers 813a and 813b.
- 7-b'] Bisbenzofuran (abbreviation: 3,10PCA2Nbf (IV) -02) was derived from the emission spectrum and showed an emission spectrum having a maximum peak near 457 nm.
- FIGS. 18 and 19 the vertical axis represents the normalized luminance (%) when the initial luminance is 100%, and the horizontal axis represents the driving time (h) of the element.
- the vertical axis shows the voltage change ( ⁇ V) when the initial voltage is 0, and the horizontal axis shows the drive time (h).
- the initial brightness was set to 5000 cd / m 2 and each light emitting device was driven.
- the device 4 shows higher reliability than the comparison device 5. Specifically, the LT95 of the device 4 was 446 hours. On the other hand, the LT95 of the comparison device 5 was less than 1 hour.
- the device 4 has a smaller long-term change in voltage and is less likely to increase in voltage than the comparative device 5.
- the third layer 823 is a Li 2 O film, during, in that it has a second layer 822 containing no Liq, a comparison device 5 ..
- the configuration in which the second layer 822 is provided between the first layer 821 and the third layer 823 is a light emitting device. It turned out that the reliability of.
- 201 substrate, 202: insulating layer, 202a: insulating layer, 202b: insulating layer, 203B: light emitting device, 203G: light emitting device, 203R: light emitting device, 203W: light emitting device, 204: insulating layer, 205: substrate, 206B: Color filter, 206G: Color filter, 206R: Color filter, 207: Space, 208: Adhesive layer, 209: Black matrix, 210: Transistor, 211: First electrode, 212G: Conductive layer, 212R: Conductive layer, 213: EL layer, 215: Second electrode, 220B: Optical distance, 220G: Optical distance, 220R: Optical distance, 301: Substrate, 302: Pixel part, 303: Circuit part, 304a: Circuit part, 304b: Circuit part, 305 : Sealing material, 306: Substrate, 307: Wiring, 308: FPC, 309:
Landscapes
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Electroluminescent Light Sources (AREA)
Abstract
Description
図2A~図2Dは、第1の層における第1の物質の濃度を説明する図である。図2E、図2Fは、第1の層及び第2の層における第1の物質の濃度を説明する図である。
図3Aは、発光装置の一例を示す上面図である。図3B、図3Cは、発光装置の一例を示す断面図である。
図4A~図4Dは、発光装置の一例を示す断面図である。
図5Aは、発光装置の一例を示す上面図である。図5Bは、発光装置の一例を示す断面図である。図5C、図5Dは、トランジスタの一例を示す断面図である。
図6A~図6Dは、電子機器の一例を示す図である。
図7A~図7Fは、電子機器の一例を示す図である。
図8A~図8Cは、電子機器の一例を示す図である。
図9A、図9Bは、実施例の発光デバイスを示す図である。
図10は、実施例1の発光デバイスの輝度−電流効率特性を示す図である。
図11は、実施例1の発光デバイスの電圧−電流特性を示す図である。
図12は、実施例1の発光デバイスの発光スペクトルを示す図である。
図13は、実施例1の発光デバイスの信頼性試験の結果を示す図である。
図14は、実施例1の発光デバイスの信頼性試験の結果を示す図である。
図15は、実施例2の発光デバイスの輝度−電流効率特性を示す図である。
図16は、実施例2の発光デバイスの電圧−電流特性を示す図である。
図17は、実施例2の発光デバイスの発光スペクトルを示す図である。
図18は、実施例2の発光デバイスの信頼性試験の結果を示す図である。
図19は、実施例2の発光デバイスの信頼性試験の結果を示す図である。
本実施の形態では、本発明の一態様の発光デバイスについて図1~図2を用いて説明する。
図1A~図1Dに、本発明の一態様の発光デバイスを示す。
第1の層1121は、第1の有機化合物と、第1の物質と、を有する。
第2の層1122は、第2の有機化合物を有する。
第3の層1123は、第2の物質を有する。
本発明の一態様の発光デバイスにおける発光モデルについて説明する。
以下では、発光デバイスに用いることができる材料について詳述する。なお、機能層1105a(正孔注入層1111a、正孔輸送層1112a)、第1の層1121、第2の層1122、第3の層1123、及び第4の層1124に用いることが好ましい材料は、それぞれ上述の通りであるが、以下に示す材料を用いてもよい。
発光デバイスの一対の電極を形成する材料としては、金属、合金、電気伝導性化合物、及びこれらの混合物などを適宜用いることができる。具体的には、In−Sn酸化物(ITOともいう)、In−Si−Sn酸化物(ITSOともいう)、In−Zn酸化物、In−W−Zn酸化物が挙げられる。その他、アルミニウム(Al)、チタン(Ti)、クロム(Cr)、マンガン(Mn)、鉄(Fe)、コバルト(Co)、ニッケル(Ni)、銅(Cu)、ガリウム(Ga)、亜鉛(Zn)、インジウム(In)、スズ(Sn)、モリブデン(Mo)、タンタル(Ta)、タングステン(W)、パラジウム(Pd)、金(Au)、白金(Pt)、銀(Ag)、イットリウム(Y)、ネオジム(Nd)などの金属、及びこれらを適宜組み合わせて含む合金を用いることもできる。その他、上記例示のない元素周期表の第1族または第2族に属する元素(例えば、リチウム(Li)、セシウム(Cs)、カルシウム(Ca)、ストロンチウム(Sr))、ユウロピウム(Eu)、イッテルビウム(Yb)などの希土類金属及びこれらを適宜組み合わせて含む合金、グラフェン等を用いることができる。
正孔注入層は、EL層に正孔を注入しやすくする機能を有する。例えば、正孔注入層は、陽極から注入された正孔を、正孔輸送層(または発光層など)に注入する機能を有することができる。例えば、正孔注入層は、正孔を発生させ、当該正孔を正孔輸送層(または発光層など)に注入する機能を有することができる。
発光層は、発光物質を含む層である。発光層は、1種または複数種の発光物質を有することができる。発光物質としては、青色、紫色、青紫色、緑色、黄緑色、黄色、橙色、赤色などの発光色を呈する物質を適宜用いる。また、発光物質として、近赤外光を発する物質を用いることもできる。
電子注入層は、EL層に電子を注入しやすくする機能を有する。例えば、電子注入層は、陰極から注入された電子を、電子輸送層(または発光層など)に注入する機能を有することができる。例えば、電子注入層は、電子を発生させ、当該電子を電子輸送層(または発光層など)に注入する機能を有することができる。
本実施の形態では、本発明の一態様の発光装置について図3~図5を用いて説明する。
図3Aに、発光装置の上面図を示し、図3B、図3Cに、図3Aの一点鎖線X1−Y1間及びX2−Y2間の断面図を示す。図3A~図3Cに示す発光装置は、例えば、照明装置に用いることができる。発光装置は、ボトムエミッション、トップエミッション、デュアルエミッションのいずれであってもよい。
図4Aに、発光装置の断面図を示す。図4Aに示す発光装置は、トランジスタと発光デバイスとが電気的に接続されてなるアクティブマトリクス型の発光装置である。
本発明の一態様の発光装置は、パッシブマトリクス型またはアクティブマトリクス型とすることができる。アクティブマトリクス型の発光装置について図5を用いて説明する。
本実施の形態では、本発明の一態様の電子機器について図を用いて説明する。
本実施例で示すデバイス1、デバイス2、及び比較デバイス3は、図9Aに示すように、基板800上に第1の電極801が形成され、第1の電極801上に正孔注入層811a、正孔輸送層812a1、正孔輸送層812a2、発光層813a、第1の層821、第2の層822、第3の層823、第4の層824、正孔注入層811b、正孔輸送層812b、発光層813b1、発光層813b2、発光層813b3、電子輸送層814b1、電子輸送層814b2、及び電子注入層815bが順次積層され、電子注入層815b上に第2の電極803が形成された構造を有する。
デバイス1、デバイス2、及び比較デバイス3の動作特性について測定した。なお、測定は室温(25℃に保たれた雰囲気)で行った。
次に、各発光デバイスに対する信頼性試験を行った。信頼性試験の結果を図13及び図14に示す。図13において、縦軸は初期輝度を100%とした時の規格化輝度(%)を示し、横軸は駆動時間(h)を示す。図14において、縦軸は初期電圧を0とした時の電圧変化(ΔV)を示し、横軸は駆動時間(h)を示す。なお、信頼性試験は、電流密度を50mA/cm2に設定し、各発光デバイスを駆動させた。
デバイス4及び比較デバイス5の動作特性について測定した。なお、測定は室温(25℃に保たれた雰囲気)で行った。
次に、各発光デバイスに対する信頼性試験を行った。信頼性試験の結果を図18及び図19に示す。図18において、縦軸は初期輝度を100%とした時の規格化輝度(%)を示し、横軸は素子の駆動時間(h)を示す。図19において、縦軸は初期電圧を0とした時の電圧変化(ΔV)を示し、横軸は駆動時間(h)を示す。なお、信頼性試験は、初期輝度を5000cd/m2に設定し、各発光デバイスを駆動させた。
Claims (23)
- 第1の電極、第1の発光層、第1の層、第2の層、第3の層、第2の発光層、及び第2の電極をこの順で積層して有し、
前記第1の層は、第1の有機化合物と、第1の物質と、を有し、
前記第2の層は、第2の有機化合物を有し、
前記第3の層は、第2の物質を有し、
前記第1の有機化合物は、電子輸送性材料であり、
前記第1の物質は、金属、金属塩、金属酸化物、または有機金属塩であり、
前記第2の有機化合物は、電子輸送性材料であり、
前記第2の物質は、電子注入性材料であり、
前記第2の層は、前記第1の層に比べて、前記第1の物質の濃度が低い、発光デバイス。 - 請求項1において、
前記第2の層は、前記第1の物質を含まない、発光デバイス。 - 請求項1または2において、
前記第1の有機化合物と前記第2の有機化合物とは、同一の有機化合物である、発光デバイス。 - 請求項1乃至3のいずれか一において、
前記第3の層は、さらに、第3の有機化合物を有し、
前記第3の有機化合物は、電子輸送性材料である、発光デバイス。 - 請求項4において、
前記第3の有機化合物は、前記第1の有機化合物及び前記第2の有機化合物の少なくとも一方と同一の有機化合物である、発光デバイス。 - 請求項1乃至5のいずれか一において、
前記第1の物質は、アルカリ金属またはアルカリ土類金属を有する、有機金属錯体である、発光デバイス。 - 請求項1乃至6のいずれか一において、
前記第1の物質は、窒素及び酸素を有する配位子と、アルカリ金属またはアルカリ土類金属と、を有する有機金属錯体である、発光デバイス。 - 請求項1乃至7のいずれか一において、
前記第1の物質は、キノリノール配位子と、アルカリ金属またはアルカリ土類金属と、を有する有機金属錯体である、発光デバイス。 - 請求項1乃至8のいずれか一において、
前記第2の物質は、アルカリ金属、アルカリ土類金属、または希土類金属を有する、発光デバイス。 - 請求項1乃至9のいずれか一において、
前記第1の有機化合物は、HOMO準位が−6.0eV以上であり、かつ電界強度[V/cm]の平方根が600における電子移動度が1×10−7cm2/Vs以上5×10−5cm2/Vs以下である、発光デバイス。 - 請求項1乃至10のいずれか一において、
前記第1の層は、前記第1の発光層側の第1の領域と、前記第2の発光層側の第2の領域と、を有し、
前記第1の領域と前記第2の領域とは、前記第1の有機化合物と前記第1の物質の濃度比が異なる、発光デバイス。 - 請求項1乃至10のいずれか一において、
前記第1の層は、前記第1の発光層側の第1の領域と、前記第2の発光層側の第2の領域と、を有し、
前記第2の領域は、前記第1の領域よりも、前記第1の物質の濃度が低い、発光デバイス。 - 請求項1乃至12のいずれか一において、
さらに、正孔注入層を有し、
前記正孔注入層は、前記第1の電極と前記第1の発光層との間に位置し、
前記正孔注入層は、第1の化合物及び第2の化合物を有し、
前記第1の化合物は、前記第2の化合物に対する電子受容性を有し、
前記第2の化合物のHOMO準位は、−5.7eV以上−5.4eV以下である、発光デバイス。 - 請求項13において、
さらに、第1の正孔輸送層を有し、
前記第1の正孔輸送層は、前記正孔注入層と前記第1の発光層との間に位置し、
前記第1の正孔輸送層は、第3の化合物を有し、
前記第3の化合物のHOMO準位は、前記第2の化合物のHOMO準位以下の値であり、
前記第3の化合物のHOMO準位と前記第2の化合物のHOMO準位との差は、0.2eV以内である、発光デバイス。 - 請求項14において、
前記第2の化合物及び前記第3の化合物は、それぞれ、カルバゾール骨格、ジベンゾフラン骨格、ジベンゾチオフェン骨格、及びアントラセン骨格のうち少なくとも一つを有する、発光デバイス。 - 請求項14において、
さらに、第2の正孔輸送層を有し、
前記第2の正孔輸送層は、前記第1の正孔輸送層と前記第1の発光層との間に位置し、
前記第2の正孔輸送層は、第4の化合物を有し、
前記第4の化合物のHOMO準位は、前記第3の化合物のHOMO準位よりも低い、発光デバイス。 - 請求項16において、
前記第2の化合物、前記第3の化合物、及び前記第4の化合物は、それぞれ、カルバゾール骨格、ジベンゾフラン骨格、ジベンゾチオフェン骨格、及びアントラセン骨格のうち少なくとも一つを有する、発光デバイス。 - 請求項1乃至17のいずれか一において、
前記第1の発光層は、青色の光を発する発光物質を有する、発光デバイス。 - 請求項1乃至18のいずれか一において、
前記第1の発光層は、青色の光を発する蛍光発光物質を有する、発光デバイス。 - 請求項1乃至19のいずれか一に記載の発光デバイスと、
トランジスタ及び基板のうち少なくとも一つと、を有する、発光装置。 - 請求項20に記載の発光装置と、
コネクタ及び集積回路のうち少なくとも一つと、を有する、発光モジュール。 - 請求項21に記載の発光モジュールと、
アンテナ、バッテリ、筐体、カメラ、スピーカ、マイク、及び操作ボタンのうち少なくとも一つと、を有する、電子機器。 - 請求項1乃至19のいずれか一に記載の発光デバイスと、
筐体、カバー、及び支持台のうち少なくとも一つと、を有する、照明装置。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202080028260.3A CN113678572A (zh) | 2019-04-12 | 2020-04-01 | 发光器件、发光装置、发光模块、电子设备以及照明装置 |
KR1020217036155A KR20210149797A (ko) | 2019-04-12 | 2020-04-01 | 발광 디바이스, 발광 장치, 발광 모듈, 전자 기기, 및 조명 장치 |
JP2021513026A JP7494165B2 (ja) | 2019-04-12 | 2020-04-01 | 発光デバイス、発光装置、発光モジュール、電子機器、及び照明装置 |
US17/598,549 US20220173347A1 (en) | 2019-04-12 | 2020-04-01 | Light-emitting device, light-emitting apparatus, light-emitting module, electronic device, and lighting device |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2019076244 | 2019-04-12 | ||
JP2019-076244 | 2019-04-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2020208474A1 true WO2020208474A1 (ja) | 2020-10-15 |
Family
ID=72751581
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/IB2020/053071 WO2020208474A1 (ja) | 2019-04-12 | 2020-04-01 | 発光デバイス、発光装置、発光モジュール、電子機器、及び照明装置 |
Country Status (5)
Country | Link |
---|---|
US (1) | US20220173347A1 (ja) |
JP (1) | JP7494165B2 (ja) |
KR (1) | KR20210149797A (ja) |
CN (1) | CN113678572A (ja) |
WO (1) | WO2020208474A1 (ja) |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007179933A (ja) * | 2005-12-28 | 2007-07-12 | Sanyo Electric Co Ltd | 有機エレクトロルミネッセント素子及び有機エレクトロルミネッセント表示装置 |
WO2009069434A1 (ja) * | 2007-11-28 | 2009-06-04 | Fuji Electric Holdings Co., Ltd. | 有機エレクトロルミネッセンス素子 |
JP2011096406A (ja) * | 2009-10-27 | 2011-05-12 | Seiko Epson Corp | 発光素子、発光装置、表示装置および電子機器 |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP5072312B2 (ja) | 2005-10-18 | 2012-11-14 | 株式会社半導体エネルギー研究所 | 有機金属錯体及びそれを用いた発光素子、発光装置 |
KR101321673B1 (ko) * | 2009-05-29 | 2013-10-23 | 가부시키가이샤 한도오따이 에네루기 켄큐쇼 | 플루오렌 유도체, 발광 소자, 발광 장치, 전자 장치, 및 조명 장치 |
CN104272488B (zh) * | 2012-05-31 | 2017-09-08 | 乐金显示有限公司 | 有机发光二极管 |
WO2015118426A2 (en) * | 2014-02-06 | 2015-08-13 | Semiconductor Energy Laboratory Co., Ltd. | Light-emitting element, lighting device, and electronic appliance |
JP6780925B2 (ja) * | 2014-07-25 | 2020-11-04 | 株式会社半導体エネルギー研究所 | 発光素子、発光装置、電子機器及び照明装置 |
US20170062749A1 (en) * | 2015-09-01 | 2017-03-02 | Semiconductor Energy Laboratory Co., Ltd. | Light-Emitting Element, Light-Emitting Device, Electronic Device, and Lighting Device |
-
2020
- 2020-04-01 JP JP2021513026A patent/JP7494165B2/ja active Active
- 2020-04-01 KR KR1020217036155A patent/KR20210149797A/ko active Search and Examination
- 2020-04-01 CN CN202080028260.3A patent/CN113678572A/zh active Pending
- 2020-04-01 WO PCT/IB2020/053071 patent/WO2020208474A1/ja active Application Filing
- 2020-04-01 US US17/598,549 patent/US20220173347A1/en active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007179933A (ja) * | 2005-12-28 | 2007-07-12 | Sanyo Electric Co Ltd | 有機エレクトロルミネッセント素子及び有機エレクトロルミネッセント表示装置 |
WO2009069434A1 (ja) * | 2007-11-28 | 2009-06-04 | Fuji Electric Holdings Co., Ltd. | 有機エレクトロルミネッセンス素子 |
JP2011096406A (ja) * | 2009-10-27 | 2011-05-12 | Seiko Epson Corp | 発光素子、発光装置、表示装置および電子機器 |
Non-Patent Citations (1)
Title |
---|
SZU-HUNG LIAO ET AL.: "Hydroxynaphthyridine-Derived Group III Metal Chelates:Wide Band Gap and Deep Blue Analogues of Green Alq3 (Tris(8- hydroxyquinolate)aluminum)and Their Versatile Applications for Organic Light-Emitting Diodes", J.AM.CHEM.SOC., vol. 131, 2008, pages 763 - 777, XP055000886, DOI: 10.1021/ja807284e * |
Also Published As
Publication number | Publication date |
---|---|
JP7494165B2 (ja) | 2024-06-03 |
US20220173347A1 (en) | 2022-06-02 |
KR20210149797A (ko) | 2021-12-09 |
JPWO2020208474A1 (ja) | 2020-10-15 |
CN113678572A (zh) | 2021-11-19 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP7066811B2 (ja) | 発光素子、表示装置、電子機器および照明装置 | |
JP6817737B2 (ja) | 発光素子、表示装置、電子機器、及び照明装置 | |
JP6650844B2 (ja) | 発光素子、表示装置、電子機器、及び照明装置 | |
CN111341927B (zh) | 发光元件、显示装置、电子设备及照明装置 | |
TWI834944B (zh) | 發光元件、顯示裝置、電子裝置、及照明設備 | |
JP6851145B2 (ja) | 発光素子、発光装置、電子機器及び照明装置 | |
JP7044475B2 (ja) | 発光素子、表示装置、電子機器、及び照明装置 | |
JP2021192435A (ja) | 発光素子、表示装置、電子機器および照明装置 | |
JP6969887B2 (ja) | 表示装置および電子機器 | |
TW201939784A (zh) | 發光元件、顯示模組、照明模組、發光裝置、顯示裝置、電子器具、及照明裝置 | |
JP7055856B2 (ja) | 発光装置 | |
JP7475281B2 (ja) | 有機化合物、発光デバイス用ホスト材料、発光デバイス、発光装置、発光モジュール、電子機器、 | |
WO2021260494A1 (ja) | 正孔注入層用複合材料、光デバイス、装置、モジュール、電子機器、及び、照明装置 | |
WO2022023864A1 (ja) | 発光デバイス、発光装置、発光モジュール、電子機器、及び、照明装置 | |
WO2020121097A1 (ja) | 発光デバイス、発光装置、電子機器、および照明装置 | |
WO2020208474A1 (ja) | 発光デバイス、発光装置、発光モジュール、電子機器、及び照明装置 | |
WO2022238804A1 (ja) | 発光デバイス、発光装置、表示装置、電子機器、照明装置 | |
WO2021171130A1 (ja) | 発光デバイス、発光装置、電子機器および照明装置 | |
JP2021014452A (ja) | 有機化合物、発光デバイス、受光デバイス、発光装置、発光モジュール、電子機器、及び照明装置 | |
JP2024096157A (ja) | 化合物 | |
KR20230137317A (ko) | 발광 디바이스, 발광 장치, 전자 기기, 표시 장치,조명 장치 | |
KR20240002705A (ko) | 발광 디바이스 |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 20788449 Country of ref document: EP Kind code of ref document: A1 |
|
ENP | Entry into the national phase |
Ref document number: 2021513026 Country of ref document: JP Kind code of ref document: A |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
ENP | Entry into the national phase |
Ref document number: 20217036155 Country of ref document: KR Kind code of ref document: A |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 20788449 Country of ref document: EP Kind code of ref document: A1 |