WO2011049141A1 - Light-emitting device equipped with organic electroluminescent element, process for production of the light-emitting device, and organic electroluminescent display device equipped with the light-emitting device - Google Patents

Light-emitting device equipped with organic electroluminescent element, process for production of the light-emitting device, and organic electroluminescent display device equipped with the light-emitting device Download PDF

Info

Publication number
WO2011049141A1
WO2011049141A1 PCT/JP2010/068519 JP2010068519W WO2011049141A1 WO 2011049141 A1 WO2011049141 A1 WO 2011049141A1 JP 2010068519 W JP2010068519 W JP 2010068519W WO 2011049141 A1 WO2011049141 A1 WO 2011049141A1
Authority
WO
WIPO (PCT)
Prior art keywords
substrate
layer
light emitting
organic
electrode
Prior art date
Application number
PCT/JP2010/068519
Other languages
French (fr)
Japanese (ja)
Inventor
秀謙 尾方
Original Assignee
シャープ株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by シャープ株式会社 filed Critical シャープ株式会社
Publication of WO2011049141A1 publication Critical patent/WO2011049141A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K59/00—Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
    • H10K59/80—Constructional details
    • H10K59/8794—Arrangements for heating and cooling

Definitions

  • the present invention relates to a light emitting device using an organic electroluminescent element, a method for manufacturing the same, and an organic electroluminescent display device including the light emitting device. More specifically, the present invention relates to a light emitting device that efficiently releases heat accompanying light emission of an organic electroluminescent element and suppresses unevenness of luminance, a method for manufacturing the same, and an organic electroluminescent display device including the light emitting device.
  • FPD thin flat panel display
  • LCD liquid crystal display
  • PDP self-luminous plasma display panel
  • inorganic EL inorganic electroluminescence
  • organic EL organic electroluminescence
  • the organic EL device includes a light emitting layer made of at least an organic compound between a pair of electrodes, and a charge injection layer that injects charges into the light emitting layer as necessary, or a charge transport that transports charges from the electrodes to the light emitting layer. Some are further provided with layers and the like.
  • the organic EL element is thin, lightweight, and has characteristics such as low-voltage driving, high luminance, and self-light emission, and therefore, research and development has been actively conducted.
  • application of organic EL elements to light sources such as electrophotographic copying machines or printers, or light emission is expected.
  • the organic EL element When an organic EL element is used for light emission, the organic EL element has surface emission, has high color rendering properties, and has an advantage that light control is easy.
  • fluorescent lamps contain mercury, but organic EL elements do not contain mercury, and there are many advantages such as that the organic EL elements do not contain ultraviolet rays.
  • Non-patent Document 1 Since Tang et al. Reported on low-voltage driven organic EL elements (Non-patent Document 1), research on organic EL elements has been actively conducted.
  • the organic EL element when a voltage is applied, energy is generated by recombination of holes injected from the anode and electrons injected from the cathode.
  • the organic EL element is a self-luminous element utilizing the principle that the light emitting layer emits light by the energy. However, the organic EL element releases 80% or more of the energy generated by recombination as heat. When the temperature in the organic EL device rises, there is a problem that the organic compound constituting the device is altered and the life of light emission is shortened.
  • the current flow increases exponentially as the temperature rises. Therefore, when a partial temperature rise occurs in the organic EL element, the current concentrates in that portion, resulting in uneven brightness due to a partial increase in emission intensity. If the temperature continues to rise further, the luminance unevenness due to deterioration or destruction of the organic EL element will be finally caused.
  • Patent Documents 1 to 4 disclose a device for releasing the heat of the organic EL element.
  • the substrate is formed of a material having higher thermal conductivity than ordinary soda glass, such as sapphire or quartz having light transmittance. According to this configuration, the heat generated from the organic EL element can be effectively radiated to the ambient air through the transparent substrate, and it is possible to sufficiently take measures against moisture, thereby deteriorating the characteristics of the organic EL element. Can improve.
  • the thermal resistance between the organic EL element and the heat absorption side of the Peltier element is set to be smaller than the thermal resistance between the organic EL element and the heat dissipation side of the Peltier element. ing.
  • the organic EL element is driven to emit light, if the Peltier element is driven at the same time, the heat generated by the light emission of the organic EL element is positively transferred to the heat dissipation side of the Peltier element by the action of the Peltier element.
  • the organic EL element is cooled. Thereby, lifetime can be improved, without reducing the brightness
  • a heat radiating means for radiating the heat of the sealing substrate for sealing the organic EL element to the outside is formed.
  • the heat dissipating means for example, heat dissipating fins, heat pipes, Peltier elements or the like can be used.
  • Patent Document 4 discloses a configuration in which a heat transfer layer is provided on the side opposite to the light emitting surface of the organic EL element.
  • the said heat-transfer layer is a layer which accelerates
  • Japanese Patent Publication “JP 10-144468 (published May 29, 1998)” Japanese Patent Publication “Japanese Patent Laid-Open No. 2004-296100 (published on October 21, 2004)” Japanese Patent Publication “Japanese Patent Laid-Open No. 2005-149853 (published on June 9, 2005)” Japanese Patent Publication “JP 2008-311076 (released on Dec. 25, 2008)”
  • Patent Documents 1 to 4 described above technologies for dissipating heat generated by light emission of the organic EL element are disclosed.
  • any of these techniques is insufficient to suppress heat generation or durability even if heat generation is suppressed. This causes problems such as a decrease in the number of times.
  • the organic EL element disclosed in Patent Document 1 is expensive in consideration of the light transmittance of the organic EL element, but sapphire or quartz is used. However, even when sapphire is used, the thermal conductivity is as high as 46 W / (m ⁇ K). A material having a higher thermal conductivity than sapphire is expensive and has a low light transmission, so it can hardly be used. Therefore, the organic EL element disclosed in this document has a limit in heat dissipation.
  • the organic EL element disclosed in Patent Document 2 the organic EL element can be cooled, but an electrode for the organic EL element and an electrode for the Peltier element must be prepared. Therefore, the manufacturing cost is increased. Furthermore, the surface of the organic EL element disclosed in this document is covered with a passivation film. In general, an organic EL element is very sensitive to oxygen or moisture. Therefore, when the organic EL element is left in the atmosphere, deterioration due to the entry of oxygen or water vapor into the organic EL element is caused. Therefore, the organic EL element disclosed in this document is covered with a passivation film as a protective film. However, since only the passivation film cannot block oxygen or moisture, the organic EL element deteriorates.
  • heat radiation means such as a heat radiation fin, a heat pipe, or a Peltier element is formed outside the sealing substrate. Therefore, since the heat generated by the light emission of the organic EL element is dissipated through the sealing substrate, the cooling efficiency is deteriorated.
  • Patent Document 4 discloses a configuration in which a heat transfer layer is provided on the side opposite to the light emitting surface of the organic EL element.
  • the heat transfer layer is formed by forming a thermally conductive polymer as a heat transfer layer by vapor deposition polymerization after an organic EL element is formed. At this time, there is a case where the organic EL element is damaged by the vapor deposition of the heat conductive polymer on the organic EL element and the light emitting performance is lowered.
  • the present invention has been made in view of the above problems, and an object of the present invention is to provide a light-emitting device that can efficiently remove the heat generated by the organic EL element during continuous driving, and a method for manufacturing the light-emitting device. And an organic electroluminescence display device including the light-emitting device.
  • a light-emitting device having at least one organic electroluminescence element formed by sequentially laminating at least a first electrode, a light-emitting layer, and a second electrode, A first external substrate formed on the light extraction side for extracting light from the light emitting layer; A conductive layer in contact with an electrode formed on the opposite side of the light extraction side of the first electrode and the second electrode, and having a work function larger than the work function of the electrode; A second external substrate disposed opposite the first external substrate and encapsulating the organic electroluminescence element together with the first external substrate; Formed on the second external substrate, having one end connected to the conductive layer, the other end extending outside the region sealed by the first external substrate and the second external substrate, and the conductive layer Wiring on the substrate having a work function equal to or higher than the work function; And an external conductive layer formed at the other end of the wiring on the substrate, having a work function smaller than that of the wiring on the
  • the organic EL element when a voltage is applied to an organic EL element, the organic EL element generates heat as the light emitting layer emits light. As the temperature in the organic EL element rises, the current flow improves exponentially. Therefore, when a partial temperature rise occurs in the organic EL element, the current concentrates in that portion, resulting in uneven brightness due to a partial increase in emission intensity.
  • the light extraction side electrode among the first electrode and the second electrode for driving the organic electroluminescence element (hereinafter also referred to as organic EL element).
  • organic EL element organic electroluminescence element
  • a conductive layer having a work function larger than that of the electrode is in contact with the conductive layer. Therefore, the electrode and the conductive layer constitute a Peltier element.
  • both are connected in series with each other, when a voltage is applied to the electrode to drive the organic EL element, the Peltier element is also driven at the same time.
  • heat generated in the organic EL element is absorbed by the conductive layer having a higher work function from the electrode on the light extraction side (Peltier effect). Further, the heat absorbed by the electrode is transferred to the first wiring to the wiring on the substrate.
  • the external conductive layer having a work function smaller than the work function of the wiring on the substrate is formed at the other end of the wiring on the substrate, the heat of the wiring on the substrate is transferred to the external conductive layer.
  • the heat of the external conductive layer is radiated by the heat dissipation structure of the external conductive layer.
  • the heat generated from the light emitting layer of the organic EL element is absorbed by the conductive layer, and the heat absorbed by the conductive layer is dissipated by the external conductive layer.
  • the partial temperature rise generated in the organic EL element can be efficiently removed, so that the light emission luminance can be made uniform. Further, since the Peltier element and the organic EL element are connected in series, both can be driven by a common power source. In addition, since the light-emitting device according to the present invention is sandwiched and sealed between two external substrates, oxygen and moisture can be prevented from entering the organic EL element even when left in the atmosphere. .
  • a method for manufacturing a light emitting device is as follows. Forming an organic electroluminescent element by forming at least a first electrode, a light emitting layer, and a second electrode on the substrate in the order of the first electrode, the light emitting layer, and the second electrode; Preparing at least one organic electroluminescence element; Forming a conductive layer having a work function larger than the work function of the second electrode on the second electrode; Contacting the first external substrate to the lower surface of the substrate; A second external substrate on which a wiring on the substrate having a work function equal to or higher than the work function of the conductive layer is formed so as to face the first external substrate so that one end of the wiring on the substrate is connected to the conductive layer.
  • a step of sealing the organic electroluminescence element The substrate having an external conductive layer having a work function smaller than a work function of the wiring on the substrate and having a heat dissipation structure extended outside a region sealed by the first external substrate and the second external substrate And a step of providing at the other end of the upper wiring.
  • a method for manufacturing a light emitting device is as follows.
  • a conductive layer having a work function larger than that of at least the first electrode, the light emitting layer, the second electrode, and the first electrode on the substrate, the conductive layer, the first electrode, the light emitting layer, and the second Forming an organic electroluminescence element including the conductive layer by forming the electrodes in order, and Preparing at least one organic electroluminescence element;
  • a step of sealing the organic electroluminescence element The substrate having an external conductive layer having a work function smaller than a work function of the wiring on the substrate and having a heat dissipation structure extended outside a region sealed by the first external substrate and the second external substrate And a step of providing at an end portion of the upper wiring.
  • the organic electroluminescence display device is characterized by including any of the light-emitting devices described above in order to solve the above-described problems.
  • an organic EL display device equipped with a light emitting device that suppresses uneven luminance of the organic EL element and heat generation of the organic EL element.
  • the Peltier effect is induced by the conductive layer, and the amount of heat absorbed at that portion also increases. As a result, the luminance can be made uniform. Furthermore, by providing an external conductive layer having a heat dissipation structure in addition to the conductive layer, the heat generation of the organic EL element can be more efficiently removed.
  • the light-emitting device according to the present invention is sandwiched and sealed between two external substrates, oxygen and moisture can be prevented from entering the organic EL element even when left in the atmosphere. .
  • the light emitting device according to the present invention it is possible to efficiently remove the heat generated from the organic EL element when continuously driven, and to provide a highly durable organic EL element.
  • FIG. 1 is a view showing a cross section of a light emitting device 20 according to the present embodiment.
  • the light emitting device 20 has a configuration in which an organic EL element 15 (organic electroluminescence element) formed on a substrate 2 is sandwiched and sealed between two external substrates 1 and 8 facing each other. Specifically, as shown in FIG. 1, an anode 3 (first electrode, second electrode), a cathode 5 (first electrode, second electrode), and an organic layer 4 (light emitting layer) are formed on a substrate 2. Each is formed in order. A conductive layer 6 exhibiting an endothermic effect is formed on the cathode 5, and an external substrate 8 (a first external substrate and a second external substrate) is formed on the conductive layer 6. Under the substrate 2, an external substrate 1 (first external substrate, second external substrate) is formed.
  • the conductive layer 6 is connected to one end of the wiring 7a (wiring on the substrate).
  • the wiring 7 a extends outside a region sealed by the external substrate 1 and the external substrate 8.
  • An external conductive layer 9 having a heat dissipation structure is connected to the other end of the wiring 7a, and a lead wiring 11b is connected to the external conductive layer 9.
  • the substrate 2 and the anode 3 are connected to the wiring 7 b formed on the external substrate 8 through the conductive portion 10.
  • the lead wiring 11a is connected to the wiring 7b.
  • the organic EL element 15 and the conductive layer 6 are connected in series. Therefore, when the organic EL element 15 is driven, the conductive layer 6 is also driven at the same time. As a result, the heat generated by the organic EL element 15 is absorbed by the conductive layer 6, and the heat absorbed by the conductive layer 6 can be dissipated by the external conductive layer 9. This detailed mechanism will be explained later.
  • the light-emitting device 20 absorbs the heat generated by the organic EL element 15 by the conductive layer 6 and the external conductive layer 9 and dissipates it in order to prevent the temperature of the organic EL element 15 from rising.
  • the detailed mechanism will be described.
  • the conductive layer 6 is formed on the cathode 5, and the conductive layer 6 and the external conductive layer 9 are connected via the wiring 7a.
  • the external conductive layer 9 has a heat sink or a heat radiating fin, and has a heat radiating structure.
  • a conductive material having a work function larger than that of the cathode 5 is used for the conductive layer 6.
  • a conductive material having a work function higher than that of the conductive layer 6 is used.
  • a conductive material having a work function smaller than that of the wiring 7a is used for the external conductive layer 9. According to this configuration, the heat generated in the light emitting layer of the organic EL element 15 is transferred to the cathode 5.
  • the conductive layer 6 has a larger work function than the cathode 5, Is absorbed by the conductive layer 6. Furthermore, since the wiring 7a has a work function higher than that of the conductive layer 6, the heat of the conductive layer 6 is absorbed by the wiring 7a. These utilize the effect (Peltier effect) in which heat is transferred from one metal to the other when a current is passed through the joint between the two types of metal. Furthermore, since the external conductive layer 9 has a smaller work function than the wiring 7 a, the heat of the wiring 7 a is transferred to the external conductive layer 9. The heat of the external conductive layer 9 is radiated by the heat dissipation structure of the external conductive layer 9. Thus, the heat generated from the light emitting layer of the organic EL element 15 is absorbed by the conductive layer 6, and the heat absorbed by the conductive layer 6 is dissipated by the external conductive layer 9.
  • the temperature rise is large in the bright portion. As the temperature rises, the current value is further increased.
  • the Peltier effect is induced by the conductive layer 6, and the heat absorption amount at that portion also increases. As a result, the luminance can be made uniform. Furthermore, by providing the external conductive layer 9 having a heat dissipation structure in addition to the conductive layer 6, the heat generation of the organic EL element 15 can be more efficiently removed.
  • a plurality of conductive layers 6 may be provided. In this case, it is necessary to use a conductive material having a higher work function as it becomes an upper layer (wiring 7a side).
  • the conductive layer 6 is provided between the cathode 5 and the external substrate 1.
  • FIG. 2 is a view showing a cross section of the organic EL element 15 in the short side direction.
  • FIG. 3 is a diagram showing a cross section of the organic EL element 15 in the long side direction.
  • the organic EL element 15 is configured by sequentially laminating an anode 3, an organic layer 4, and a cathode 5 on a substrate 2, and the organic layer 4 includes at least a light emitting layer 4c. Is included.
  • the organic layer 4 may include other layers in addition to the light emitting layer 4c. Each layer does not have to be a single layer and may have a multilayer structure. For example, the following configuration is also possible.
  • Anode / hole transport layer / light emitting layer / electron transport layer / cathode (2) Anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode (3) anode / Hole injection layer / hole transport layer / electron blocking layer / light emitting layer / hole blocking layer / electron injection layer / cathode
  • the cross section of the organic EL element 15 which has the electron blocking layer 4d / electron carrying layer 4e / cathode 5 is shown.
  • the hole injection layer 4a is a layer for efficiently receiving holes from the anode 3 and efficiently injecting holes into the light emitting layer 4c.
  • the hole transport layer 4b is a layer for efficiently receiving holes from the anode 3 and efficiently transferring holes to the light emitting layer 4c.
  • the electron injection layer is a layer for efficiently receiving electrons from the cathode 5 and efficiently injecting electrons into the light emitting layer 4c.
  • the electron transport layer 4e is a layer that efficiently receives electrons from the cathode 5 and efficiently delivers electrons to the light emitting layer 4c.
  • the hole blocking layer 4d is a layer that prevents holes from passing through the cathode 5 without recombining with electrons, and the electron blocking layer prevents electrons from passing through the anode 3 without recombining with holes. It is a blocking layer.
  • the organic layer 4 may include a charge generation layer.
  • the charge generation layer is a layer having a function of maintaining the inside of the organic layer 4 at a substantially equal potential when receiving light, and injecting holes from one main surface and electrons from the other main surface. Therefore, if a charge generation layer is provided between the light emitting layers 4c, recombination of holes and electrons can be induced by injecting holes into the cathode 5 and injecting electrons into the anode. it can.
  • the light extraction from the light emitting layer 4c may be performed from either the anode 3 side or the cathode 5 side. Therefore, either a bottom emission type or a top emission type may be used.
  • the conductive layer 6 is formed so as to be in contact with the electrode formed on the side opposite to the light extraction side among the anode 3 side and the cathode 5.
  • each member of the light-emitting device 20 is demonstrated in detail.
  • the substrate 2 of the organic EL element 15 a glass substrate, a metal substrate, a flexible substrate, or the like is used. However, when using a roll-to-roll method, a flexible substrate is preferable.
  • flexible substrates include plastic films such as OPP (stretched polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), or PPS (polyphenylene sulfite), quartz glass films, or a film in which glass and a film are laminated. is there.
  • the substrate 2 is preferably a substrate having insulating properties and high light transmittance.
  • a protective film such as a SiO 2 (silicon oxide) film that prevents elution of alkali oxide from the film substrate.
  • a metal electrode formed of a metal having a high work function in order to inject holes into the light emitting layer 4c more efficiently.
  • Au gold
  • Ag silver
  • Pt platinum
  • Ni nickel
  • a transparent electrode may be used to extract light from the light emitting layer 4c from the anode 3 side.
  • transparent conductive materials such as ITO (indium tin oxide), IDIXO (Idemitsu Kosan Co., Ltd., Idemitsu transparent conductive material), GZO (gallium-doped zinc oxide), or SnO 2 (tin oxide).
  • an electrode in which a metal having a low work function and a stable metal are stacked there are Ca (calcium) / Al (aluminum), Ce (cerium) / Al, Cs (cesium) / Al, Ba (barium) / Al, etc. as a combination of metals to be laminated.
  • an electrode containing a metal having a low work function may be used.
  • LiF (lithium fluoride) / Al LiF / Ca / Al
  • BaF 2 (barium fluoride) / Ba / Al or LiF / Al / Ag.
  • a dry process such as a vapor deposition method, an EB (electron beam) method, an MBE (electron beam melting) method, or a sputtering method, a spin coating method, a printing method, an ink jet method, or the like is used.
  • a wet process can be used.
  • a conductive material having a work function larger than that of the cathode 5 is used for the conductive layer 6.
  • the conductive material include Au (gold), Ag (silver), ITO (indium tin oxide), and the like.
  • the hole injection layer 4a is preferably a material having a work function between the work function of the anode 3 and the HOMO (highest occupied level) level of the light emitting layer 4c.
  • an inorganic p-type semiconductor material a porphyrin compound, TPD (N, N′-bis- (3-methylphenyl) -N, N′-bis- (phenyl) -benzidine), or NPD (N, N′-diethyl) (Naphthalen-1-yl) -N, N′-diphenyl-benzidine) and other low molecular weight materials such as aromatic tertiary amine compounds, hydrazone compounds, quinacridone compounds, or styrylamine compounds, PANI (polyaniline), PEDT / Polymer materials such as PSS (3,4-polyethylenedioxythiophene / polystyrene sulfonate), Poly-TPD (poly [triphenylamine derivative]), or PVCz (polyvinylcarbazole), Pre-PPV (poly (p- Phenylene vinylene) precursor), or Pre-PNV (poly (p-naphthalene vinylen
  • the hole injection layer 4a can be formed by a dry process such as a direct vapor deposition method using at least one of the above hole injection materials. It should be noted that there is no problem even if the hole injection layer 4a is formed by using two or more kinds of the hole injection materials. In this case, an additive such as a donor or an acceptor may be contained.
  • the hole injection layer forming coating solution may contain two or more of the above hole injection materials.
  • the hole injection layer forming coating solution may contain a binding resin, a leveling agent, an additive, or the like.
  • the binding resin for example, polycarbonate or polyester can be used.
  • a donor or an acceptor etc. can be used as an additive.
  • the solvent for the hole injection layer forming coating solution may be any solvent that can dissolve or disperse the hole injection material. For example, pure water, methanol, ethanol, THF (tetrahydrofuran), chloroform, xylene, trimethylbenzene, or the like can be used.
  • the LUMO level of the hole transport layer 4b lower than the LUMO level of the light emitting layer 4c.
  • the band gap of the hole transport layer 4b is larger than the band gap of the light emitting layer 4c.
  • hole transport materials include N, N′-bis (3-methylphenyl) -N, N′-bis (phenyl) -benzidine (TPD), or N, N′-di (naphthalen-1-yl) And aromatic tertiary amine compounds such as —N, N′-diphenyl-benzidine (NPD).
  • the hole transport layer 4b can be formed by a dry process such as a direct vapor deposition method using at least one hole transport material satisfying the above conditions. Note that there is no problem even if the hole transport layer 4b is formed by using two or more hole transport materials satisfying the above conditions. In this case, an additive such as a donor or an acceptor may be contained.
  • the coating liquid for hole transport layer formation may contain 2 or more types of hole transport materials which satisfy
  • the hole transport layer forming coating solution may contain a binding resin, a leveling agent, or an additive.
  • the binding resin for example, polycarbonate, polyester or the like can be used.
  • a donor or an acceptor etc. can be used as an additive.
  • the solvent for the coating liquid for forming the hole transport layer may be any solvent that can dissolve or disperse the hole transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
  • the same material as the hole injection material can be used.
  • the electron blocking layer it is preferable to use a material in which the absolute value of the LUMO (lowest vacancy level) level is smaller than the absolute value of the LUMO level of the hole injection layer 4a in contact with the electron blocking layer.
  • the absolute value of the LUMO (lowest vacancy level) level is smaller than the absolute value of the LUMO level of the hole injection layer 4a in contact with the electron blocking layer.
  • the electrical blocking layer can be formed by a dry process such as a direct vapor deposition method using at least one type of electron blocking material that satisfies the above conditions.
  • a dry process such as a direct vapor deposition method using at least one type of electron blocking material that satisfies the above conditions.
  • an electron blocking layer forms an electron blocking layer using two or more types of electron blocking materials which satisfy
  • the coating liquid for forming an electron blocking layer may contain 2 or more types of electron blocking materials which satisfy
  • the coating solution for forming an electron blocking layer may contain a binding resin, a leveling agent, or an additive.
  • the binding resin for example, polycarbonate, polyester or the like can be used.
  • a donor or an acceptor etc. can be used as an additive.
  • the solvent for the electron blocking layer-forming coating solution may be any solvent that can dissolve or disperse the hole transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
  • a light emitting material generally used in an organic EL device can be used.
  • a low molecular light emitting material, a polymer light emitting material, or a precursor of a polymer light emitting material is used. Can also be used.
  • low-molecular light emitting material examples include aromatic dimethylidene compounds such as DPVBi (4,4′-bis (2,2′-diphenylvinyl) -biphenyl), 5-methyl-2- [2- [4- (5 Oxadiazole compounds such as -methyl-2-benzoxazolyl) phenyl] vinyl] benzoxazole, TAZ (3- (4-biphenylyl) -4-phenyl-5-t-butylphenyl-1,2,4 -Triazole derivatives such as triazole), styrylbenzene compounds such as 1,4-bis (2-methylstyryl) benzene, thiopyrazine dioxide derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, diphenoquinone derivatives, or fluorenone derivatives Organic material, azomethine zinc complex, or Alq 3 ((8-hydroxyquino Fluorescent organic metal compounds such as lina),
  • polymer light-emitting materials include poly (2-decyloxy-1,4-phenylene) DO-PPP, PPP-NEt 3 + (poly [2,5-bis- [2- (N, N, N-triethyl).
  • Examples of the precursor of the polymer light emitting material include a PPV precursor, a PNV precursor, a PPP precursor, and the like.
  • the light emitting layer 4c emits a specific color depending on its type, but the light emitting device 20 may be provided with a combination of a plurality of light emitting layers 4c that emit different colors.
  • a light emitting device 20 that emits white light can be obtained by combining a blue light emitting layer 4c, a green light emitting layer 4c, and a red light emitting layer 4c.
  • the light emitting layer 4c can be formed using at least one of the above light emitting materials. Note that there is no problem even if two or more kinds of the light emitting materials are used. Further, for the light emitting layer 4c, at least one kind of hole transport material or electron transport material may be used instead of the light emitting material. In this case, there is no problem even if two or more hole transport materials or electron transport materials are used.
  • the light emitting layer 4c can be formed by a dry process such as a direct vapor deposition method using at least a light emitting material, a hole transport material, or an electron transport material.
  • a dry process such as a direct vapor deposition method using at least a light emitting material, a hole transport material, or an electron transport material.
  • a wet process using a coating solution for forming the light emitting layer 4c in which at least a light emitting material, a hole transport material, or an electron transport material is dissolved in a solvent.
  • the coating liquid for forming the light emitting layer 4c may contain two or more kinds of light emitting materials, hole transport materials, or electron transport materials.
  • the coating liquid for forming the light emitting layer 4c may contain a binding resin, a leveling agent, an additive, or the like.
  • the binding resin for example, polycarbonate, polyester or the like can be used. Moreover, a donor or an acceptor etc. can be used as an additive.
  • the solvent for the coating solution for forming the light emitting layer 4c may be any solvent that can dissolve or disperse the light emitting material, the hole transport material, or the electron transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
  • the hole transport material of the light emitting layer 4c can use the material similar to the hole transport material used for the hole transport layer 4b.
  • the electron transport material of the light emitting layer 4c the same material as the electron transport material used for the electron transport layer 4e can be used.
  • the same material as the following electron transport material can be used for the hole blocking layer 4d.
  • hole blocking materials examples include 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), or bis (2-methyl-8-quinolinolate) (p-phenylphenolate) aluminum ( III) (BAlq) and the like.
  • the hole blocking layer 4d When the hole blocking layer 4d is formed, the hole blocking layer 4d having a thickness of about 10 nm can be formed between the light emitting layer 4c and the electron transport layer 4e by, for example, BCP using a vacuum deposition method. .
  • the electron transport layer 4e efficiently receives electrons from the electron injection layer and efficiently delivers them to the light emitting layer 4c. Therefore, it is preferable to use a material having a LUMO level between the LUMO level of the electron injection layer and the LUMO level of the light emitting layer 4c. Thereby, electrons can be injected and transported to the light emitting layer 4c more efficiently, and the voltage of the organic EL element 15 can be reduced or the light emission efficiency can be increased.
  • the HOMO level of the electron transport layer 4e higher than the HOMO level of the light emitting layer 4c.
  • the band gap of the electron transport layer 4e is larger than the band gap of the light emitting layer 4c.
  • electron transport materials include inorganic materials that are n-type semiconductors, low molecular weight materials such as oxadiazole derivatives, triazole derivatives, thiopyrazine dioxide derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, diphenoquinone derivatives, or fluorenone derivatives, Examples thereof include a polymer material such as Poly-OXZ (poly (oxadiazole)) or PSS (polystyrene derivative).
  • the electron transport layer 4e can be formed by a dry process such as a direct vapor deposition method using at least one of the above electron transport materials. Note that there is no problem even if the electron transport layer 4e is formed by using two or more kinds of the electron transport layer 4e. In this case, an additive such as a donor or an acceptor may be contained.
  • the coating liquid for electron transport layer formation may contain the said electron transport material 2 or more types.
  • the coating liquid for forming an electron transport layer may contain a binding resin, a leveling agent, or an additive.
  • the binding resin for example, polycarbonate, polyester or the like can be used.
  • a donor or an acceptor etc. can be used as an additive.
  • the solvent for the electron transport layer forming coating solution may be any solvent that can dissolve or disperse the electron transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
  • the electron injection layer it is preferable to use a material having a higher LUMO energy level than the electron transport layer 4e in order to perform electron injection / transport more efficiently. Furthermore, it is preferable to use a material whose electron moving speed is lower than that of the electron transporting material.
  • the electron injection material include fluorides such as LiF (lithium fluoride) or BaF 2 (barium fluoride), and oxides such as Li 2 O (lithium oxide).
  • the charge generation layer has a function of maintaining the organic layer 4 at a substantially equipotential during light reception and injecting holes from one main surface and electrons from the other main surface.
  • the charge generation layer one having one surface having hole injection properties and the other surface having electron injection properties is used.
  • transparent electrodes such as Mg (magnesium), Ag, Al, Mg—Ag alloy, Mg—Al alloy (magnesium-aluminum alloy), thin film metal such as Al—Li alloy, ITO, or IZO (indium zinc oxide)
  • an electron injecting compound such as an electron transporting compound such as an oxylene metal complex or an N-containing ring compound, an alkali metal, an alkaline earth metal, a rare earth metal, or a compound containing these.
  • TCNQ (7,7,4) is added to a hole transporting material such as 2-TNATA (4,4 ′, 4 ′′ -tris [N, N- (2-naphthyl) phenylamino] triphenylamine) or NPD.
  • the charge generation layer can be formed by a dry process such as a direct vapor deposition method using at least one of the above charge generation materials. Note that there is no problem even if the charge generation layer is formed by using two or more kinds of the charge generation materials.
  • the charge generation layer may be conductive, semiconductive, or electrically insulating.
  • the coating liquid for charge generation layer formation may contain two or more kinds of the above-described charge generation / transport materials.
  • the coating solution for forming the charge generation layer may contain a binding resin, a leveling agent, an additive, or the like.
  • the binding resin for example, polycarbonate, polyester or the like can be used.
  • a donor or an acceptor etc. can be used as an additive.
  • the solvent for the charge generation layer forming coating solution may be any solvent that can dissolve or disperse the charge generation material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
  • At least one of the two substrates may be light transmissive. Therefore, it is sufficient that at least the substrate on the light extraction side of the light emitting device 20 is transparent.
  • glass, resin, a metal substrate, or the like can be used.
  • a glass, resin, metal substrate or the like conventionally used for sealing can be used for the substrate on the side where the organic EL element 15 is sealed.
  • the thermal conductivity is high.
  • a metal substrate such as aluminum or stainless steel, or ceramics is preferred. Further, it is more preferable to arrange graphite or the like having a high emissivity on the outside thereof.
  • the external substrates 1 and 8 may be flat or curved and may have a bent portion.
  • substrate on the side which seals the organic EL element 15 can use the method of bonding together with a thermosetting resin or UV curable resin, or a glass fusion method, for example.
  • the method of mixing moisture absorbents, such as a calcium oxide, in inert gas can be used.
  • a dry process such as a vacuum deposition method has been shown as a method for forming each organic layer 4, but a wet process such as a doctor blade method, a dip coating method, a micro gravure method, a spray method, an ink jet method, or a printing method is used. Can be used.
  • a wet process such as a doctor blade method, a dip coating method, a micro gravure method, a spray method, an ink jet method, or a printing method is used.
  • after forming the organic layer 4 it is preferable to heat-dry in order to remove a residual solvent.
  • the heat drying is preferably performed in an inert gas from the viewpoint of preventing deterioration of the organic material.
  • the organic EL element 15 to be mounted on the light emitting device 20 is formed.
  • the organic EL element 15 according to this embodiment is preferably formed by a roll-to-roll method.
  • the substrate 2 on which the anode 3 is previously formed is set in a roll-to-roll vapor deposition apparatus. Thereafter, the set substrate 2 is transported at a constant speed.
  • Each organic layer 4 and cathode 5 are formed in order on the anode 3 of the substrate 2 that has been transported, and a strip-shaped organic EL element 15 is formed.
  • a conductive layer 6 having a work function larger than that of the cathode 5 is formed on the cathode 5 of the organic EL element 15 and is wound up again in a roll shape. In this way, a strip-shaped organic EL element 15 having the conductive layer 6 is completed.
  • each layer can be finished to a desired film thickness by controlling the vapor deposition rate when forming each organic layer 4, cathode 5 and conductive layer 6.
  • a protective film may be formed in order to prevent damage such as damage due to moisture from the outside or scratches due to physical contact when winding the roll.
  • a protective film may be attached to the surface of the organic EL element 15 and then wound in a roll shape.
  • the protective film include metal thin films such as Al and Ag, organic films such as phthalocyanine, or inorganic films such as SiON (silicon oxynitride), SiO (silicon monoxide), and SiN (silicon nitride).
  • Examples of the method for forming the protective film include EB vapor deposition, sputtering, ion plating, and resistance heating vapor deposition.
  • Examples of the protective layer include metal thin films such as Al and Ag, organic films such as phthalocyanine, and inorganic films such as SiON, SiO, and SiN.
  • Examples of the formation method include EB vapor deposition, sputtering, ion plating, and resistance heating vapor deposition.
  • At least one organic EL element 15 is prepared. Specifically, the strip-shaped organic EL element 15 is divided, and the organic EL elements 15 are divided into one by one.
  • An external substrate 8 is disposed on the conductive layer 6 of the divided organic EL element 15.
  • Wirings 7 a and 7 b are formed on the external substrate 8. When the external substrate 8 is disposed on the conductive layer 6, the conductive layer 6 and the wirings 7a and 7b are aligned and disposed. At this time, one end of the wiring 7 a is connected to the conductive layer 6. According to this configuration, the cathode 5 is electrically connected to the wiring 7 a through the conductive layer 6.
  • the wiring 7a extends outside the region sealed by the external substrate 1 and the external substrate 8 described below, and an external conductive layer 9 having a work function smaller than that of the wiring 7a is formed at the other end of the wiring 7a. ing.
  • a lead wiring 11 b is connected to the external conductive layer 9.
  • the external conductive layer 9 is connected to an insulated heat sink or heat radiating fin, and has a heat radiating structure (not shown). With the heat dissipation structure, the heat absorbed by the wiring 7a can be dissipated.
  • a heat sink or a heat radiating fin is directly connected to the other end of the wiring 7a, and the lead wiring 11b is further connected to the wiring 7a. May be. In this case, since the heat absorbed by the wiring 7a can be radiated by the heat dissipation structure of the lead wiring 11b, the external conductive layer 9 may not be provided.
  • the anode 3 of the organic EL element 15 is connected to the wiring 7b through the conductive portion 10.
  • a film-like conductive resin material is used as the conductive portion 10, and the anode 3 and the wiring 7b are connected by thermocompression bonding of the anode 3 and the wiring 7b through the resin material.
  • the lead wiring 11a is connected to the wiring 7b.
  • the external substrate 1 is brought into contact with and fixed to the external substrate 8 having the organic EL element 15, specifically, the upper surface of the substrate 2. At this time, the space between the external substrate 1 and the external substrate 8 is sealed with a UV curable resin or the like.
  • the bottom emission type light-emitting device 20 is manufactured.
  • the roll-to-roll method since the organic EL element 15 can be continuously produced on the substrate 2, a large vapor deposition apparatus is not necessary, and the initial investment cost can be suppressed. Furthermore, in this manufacturing method, material utilization efficiency is high and a patterning mask is not required, so that it can be manufactured at low cost.
  • the light emitting device 20 obtained by the manufacturing method described above is a bottom emission type
  • FIG. 4 is a cross-sectional view of the top emission type light emitting device 20. The manufacturing method will be described below.
  • the organic EL element 15 to be mounted on the light emitting device 20 is formed.
  • the organic EL element 15 according to this embodiment is preferably formed by a roll-to-roll method.
  • the procedure first, the substrate 2 is set in a roll-to-roll vapor deposition apparatus. Thereafter, the set substrate 2 is transported at a constant speed. A conductive layer 6 having a work function larger than that of the cathode 5 is formed on the substrate 2 that has been transported. Then, the cathode 5 is formed on the conductive layer 6, the organic layers 4 and the anode 3 are sequentially formed, and the band-shaped organic EL element 15 is formed. The obtained strip-shaped organic EL element 15 is again wound into a roll. In this way, a strip-shaped organic EL element 15 having the conductive layer 6 is completed.
  • At least one organic EL element 15 is prepared. Specifically, the strip-shaped organic EL element 15 is divided, and the organic EL elements 15 are divided into one by one.
  • An external substrate 8 is arranged under the substrate 2 of the divided organic EL element 15.
  • Wirings 7 a and 7 b are formed on the external substrate 8. At this time, one end of the wiring 7b is connected to the conductive layer 6 through the conductive portion 10a.
  • the conductive portion 10a having a thickness of about 200 ⁇ m is formed by screen printing using a silver paste wiring member made of silver fine particles and a binder resin.
  • the conductive layer 6 and the wiring 7b are connected by thermocompression bonding the conductive portion 10a between the conductive layer 6 and the wiring 7b. According to this configuration, the cathode 5 is electrically connected to the wiring 7 b through the conductive layer 6.
  • the wiring 7b extends outside a region sealed by the external substrate 1 and the external substrate 8, and an external conductive layer 9 having a work function smaller than that of the wiring 7b is formed at the other end of the wiring 7b.
  • a lead wiring 11 a is connected to the external conductive layer 9.
  • the external conductive layer 9 is connected to an insulated heat sink or heat radiating fin, and has a heat radiating structure (not shown). With the heat dissipation structure, the heat absorbed by the wiring 7b can be dissipated.
  • a material smaller than the work function of the wiring 7b is used as the extraction wiring 11a, a heat sink or a heat radiation fin is directly connected to the other end of the wiring 7b, and the extraction wiring 11a is further connected to the wiring 7b. May be. In this case, since the heat absorbed by the wiring 7b can be radiated by the heat dissipation structure of the lead wiring 11b, the external conductive layer 9 may not be provided.
  • the anode 3 of the organic EL element 15 is connected to the wiring 7a through the conductive portion 10b. Specifically, the anode 3 and the wiring 7a are connected by forming the conductive portion 10b in the same manner as the conductive portion 10a. Note that the wiring 7a extends to the outside of the region sealed by the external substrate 1 and the external substrate 8 described below, and a lead-out wiring 11b is connected to the other end of the wiring 7a. Finally, the external substrate 1 is abutted and fixed on the external substrate 8 having the organic EL element 15, specifically, the upper surface of the anode 3. At this time, the space between the external substrate 1 and the external substrate 8 is sealed with a UV curable resin or the like.
  • the top emission type light emitting device 20 is manufactured.
  • two or more organic EL elements 15 can be mounted on the light emitting device 20 according to the present embodiment.
  • organic EL elements 15 that are complementary colors may be combined and disposed on the substrate 2.
  • the three organic EL elements 15, that is, the organic EL element 15 that emits red light, the organic EL element 15 that emits green light, and the organic EL element 15 that emits blue light may be combined and disposed on the substrate 2.
  • the color of light emitted from the light emitting device 20 can be arbitrarily adjusted, and color rendering can be improved.
  • the organic EL element 15 is preferably provided with an auxiliary electrode locally or entirely along the long side direction. As a result, the voltage drop due to the resistance of the electrode can be reduced, and unevenness in the light emission of the organic EL element 15 can be eliminated.
  • a metal such as Al, Au, Ag, or Cu having excellent conductivity can be used.
  • the conductive layer is formed on the second electrode, and the light is extracted from the first electrode side.
  • the light emitting device according to the present invention can be realized as a bottom emission type light emitting device.
  • the conductive layer is formed between the substrate and the first electrode, and the light is extracted from the second electrode side.
  • the light emitting device according to the present invention can be realized as a top emission type light emitting device.
  • the wiring on the substrate has a work function larger than a work function of the conductive layer.
  • the first wiring absorbs the heat absorbed by the conductive layer more efficiently. Therefore, the heat generated by the organic EL element can be removed more efficiently.
  • the heat dissipation structure is any one of a heat dissipation fin and a heat sink.
  • the external conductive layer can dissipate heat efficiently, and the heat generation of the induced EL element can be efficiently removed.
  • the organic electroluminescence element is preferably formed by a roll-to-roll method.
  • the organic EL element according to the present invention can be continuously mass-produced, the manufacturing cost can be suppressed.
  • Example 1 A substrate having a lower electrode (anode) made of ITO on the surface of a 10 m ⁇ 20 mm PET film was prepared.
  • the film substrate was subjected to ultrasonic cleaning for 10 minutes using acetone and IPA (isopropyl alcohol). Thereafter, UV ozone cleaning was performed for 30 minutes.
  • the cleaned film substrate was set in a roll-to-roll vapor deposition apparatus, and the film substrate was conveyed at a constant speed of 1 m / sec.
  • a hole injection layer having a thickness of about 30 nm was formed on the surface of the anode on the conveyed film substrate using CuPc (copper phthalocyanine) by vacuum deposition.
  • a hole transport layer having a thickness of about 20 nm is formed on the hole injection layer using ⁇ -NPD (4′-bis [N- (1-naphthyl) -N-phenyl-amino] biphenyl)). It formed by the vacuum evaporation method.
  • An electron blocking layer having a thickness of about 30 nm is formed on the hole transport layer using HMTPD (4,4′-bis- [N, N ′-(3-tolyl) amino-3,3′-dimethylbiphenyl]. Was formed by vacuum evaporation.
  • the charge transporting red light emitting layer includes ⁇ -NPD (hole transport material) and TAZ (3-phenyl-4 (1′-naphthyl) -5-phenyl-1,2,4-triazole) (electron transport material).
  • the charge transporting green light emitting layer includes ⁇ -NPD (hole transport material), TAZ (electron transport material), Ir (ppy) 3 (tri (2-phenylpyridine) iridium) (green light emitting dopant), and Were formed by co-deposition by controlling the ratio of the respective deposition rates to be 1.0: 1.0: 0.1.
  • a both charge transporting blue light emitting layer having a thickness of about 10 nm was formed by vacuum deposition.
  • the dual charge transporting blue light emission includes ⁇ -NPD (hole transport material), TAZ (electron transport material) and t-BuPBD (2- (4′-t-butylphenyl) -5- (4 ′′ -biphenylyl). ) -1,3,4-oxadiazol) (blue light emitting dopant), and the ratio of the respective vapor deposition rates is controlled to be 1.5: 0.5: 0.2 and co-deposited. This formed a white light-emitting layer.
  • a hole blocking layer having a thickness of about 10 nm was formed on the light emitting layer by vacuum deposition using BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline).
  • an electron transport layer having a thickness of about 30 nm was formed on the hole blocking layer by using Alq 3 (tris (8-hydroxyquinoline) aluminum).
  • an electron injection layer having a thickness of about 1 nm was formed by vacuum deposition using LiF.
  • Platinum-palladium having a work function larger than that of aluminum was deposited on the cathode of the formed strip-shaped organic EL element to a thickness of 2000 mm or less. As a result, a conductive layer was formed on the cathode of the strip-shaped organic EL element.
  • a strip-shaped organic EL element having a conductive layer was divided into 15 cm lengths to obtain six organic EL elements.
  • the obtained organic EL element was fixed on the glass substrate at intervals of 5 mm. At this time, the cathode side was brought into contact with the glass substrate.
  • platinum-palladium wiring is formed in advance, and the wiring is electrically connected in parallel to the anode and cathode of each organic EL element.
  • An aluminum layer was formed on platinum-palladium as an external electrode layer at the end of the wiring connected to the cathode.
  • a glass substrate for sealing was fixed using a UV curable resin on a glass substrate having an organic EL element, and fins for heat dissipation were connected to the external electrode layer. At this time, in order to prevent deterioration due to moisture or the like, the operation was performed in a dry air boot.
  • Example 1 After forming a strip-shaped organic EL device in the same manner as in Example 1, the strip-shaped organic EL device was divided into 15 cm lengths without depositing platinum-palladium on the cathode, and six organic EL devices were obtained. Got. Each organic EL element was fixed on a glass substrate in the same manner as in Example 1. At this time, aluminum wiring was previously formed on the glass substrate. And the glass substrate for sealing was fixed on the glass substrate which has an organic EL element like Example 1, and the fin for thermal radiation was connected to the external electrode layer.
  • the light emitting device of Comparative Example 1 does not have a conductive layer, aluminum wiring is connected on the aluminum electrode (cathode). Further, an aluminum layer is formed as an external electrode layer at the end of the aluminum wiring. Therefore, the cathode, the wiring, and the external electrode layer are all made of aluminum, and there is no difference in work function.
  • the light emitting device of Example 1 has a conductive layer having a work function larger than that of the cathode on the cathode, and an aluminum layer is formed as an external electrode layer at the end of the wiring. Therefore, the work function of the conductive layer is larger than that of the cathode, and the work function of the external electrode layer is smaller than that of the wiring.
  • the heat generated in the organic EL element is transferred to the cathode.
  • the conductive layer has a larger work function than the cathode, the heat of the cathode is absorbed by the conductive layer.
  • the heat of the wiring is immediately transferred to the external conductive layer because the external conductive layer has a smaller work function than the wiring. Then, the heat of the external electrode layer is radiated by the heat dissipation fin of the external electrode layer.
  • the temperature of the organic EL element when the light emitting device of Example 1 is driven for 10 minutes is as low as 30 degrees, whereas the temperature of the organic EL element when the light emitting device of Comparative Example 1 is driven for 10 minutes. was as high as 43 degrees.
  • the light emitting device according to the present invention can be used, for example, for a display device using an organic electroluminescence element.

Landscapes

  • Electroluminescent Light Sources (AREA)

Abstract

Disclosed is a light-emitting device (20) having at least one organic El element (15) mounted thereon. In the organic El element (15), at least an anode (3), a cathode (5) and an organic layer (4) comprising a light-emitting layer are laminated on a substrate (2). An electrically conductive layer (6) having a higher work function than that of the cathode (5) is provided on the cathode (5), and an external substrate (1) is in contact with the lower surface of the substrate (2). Another external substrate (8) is arranged further above the electrically conductive substrate (6), and both the external substrate (8) and the external substrate (1) seal the organic El element (15). The electrically conductive layer (6) is connected to the external substrate (8) through a wiring (7a), an external electrically conductive layer (9) having a lower work function than that of the wiring (7a) and having a heat dissipating structure is connected to the wiring (7a). The anode (3) is connected to the external substrate (8) through the wiring (7b).

Description

有機エレクトロルミネッセンス素子を用いた発光装置、およびその製造方法、ならびに該発光装置を備えた有機エレクトロルミネッセンス表示装置LIGHT EMITTING DEVICE USING ORGANIC ELECTROLUMINESCENT ELEMENT, ITS MANUFACTURING METHOD, AND ORGANIC ELECTROLUMINESCENT DISPLAY DEVICE EQUIPPED WITH THE LIGHT EMITTING DEVICE
　本発明は、有機エレクトロルミネッセンス素子を用いた発光装置、およびその製造方法、ならびに該発光装置を備えた有機エレクトロルミネッセンス表示装置に関する。より詳しくは、有機エレクトロルミネッセンス素子の発光に伴う熱を効率的に放出し、輝度むらを抑えた発光装置、およびその製造方法、ならびに該発光装置を備えた有機エレクトロルミネッセンス表示装置に関するものである。 The present invention relates to a light emitting device using an organic electroluminescent element, a method for manufacturing the same, and an organic electroluminescent display device including the light emitting device. More specifically, the present invention relates to a light emitting device that efficiently releases heat accompanying light emission of an organic electroluminescent element and suppresses unevenness of luminance, a method for manufacturing the same, and an organic electroluminescent display device including the light emitting device.
　近年では、従来主流であったブラウン管を使用した表示装置から、薄型のフラットパネルディスプレイ（ＦＰＤ）の表示装置のニーズが高まりつつある。ＦＰＤには、非自発光型の液晶ディスプレイ（ＬＣＤ）、自発光型のプラズマディスプレイパネル（ＰＤＰ）、無機エレクトロルミネッセンス（無機ＥＬ）ディスプレイ、または有機エレクトロルミネッセンス（有機ＥＬ）ディスプレイ等が知られている。中でも、有機ＥＬ素子は、薄型であり、軽量であるという利点から、有機ＥＬ素子を利用したＦＰＤの進歩は特に著しい。 In recent years, there has been a growing need for thin flat panel display (FPD) display devices from the conventional display devices using cathode ray tubes. As the FPD, a non-self-luminous liquid crystal display (LCD), a self-luminous plasma display panel (PDP), an inorganic electroluminescence (inorganic EL) display, an organic electroluminescence (organic EL) display, or the like is known. . Among them, the progress of FPD using the organic EL element is particularly remarkable because of the advantage that the organic EL element is thin and lightweight.
　有機ＥＬ素子は、一対の電極間に、少なくとも有機化合物から成る発光層を備えており、必要に応じて発光層に電荷を注入する電荷注入層、または電極から発光層に電荷を輸送する電荷輸送層等をさらに備えたものもある。前述したように、有機ＥＬ素子は、薄型であり、軽量であり、なおかつ低電圧駆動、高輝度および自発光等の特性を有していることから、その研究開発が盛んに行われている。特に、最近では、電子写真複写機、またはプリンター等の光源、または発光等への有機ＥＬ素子の応用が期待されている。有機ＥＬ素子を発光に用いた場合、有機ＥＬ素子は面発光であり、高い演色性を示し、なおかつ調光が容易であるという利点がある。さらには、蛍光灯は水銀を含んでいるが、有機ＥＬ素子は水銀を含んでおらず、有機ＥＬ素子の発光には紫外線を含まない等、優位な点が多い。 The organic EL device includes a light emitting layer made of at least an organic compound between a pair of electrodes, and a charge injection layer that injects charges into the light emitting layer as necessary, or a charge transport that transports charges from the electrodes to the light emitting layer. Some are further provided with layers and the like. As described above, the organic EL element is thin, lightweight, and has characteristics such as low-voltage driving, high luminance, and self-light emission, and therefore, research and development has been actively conducted. In particular, recently, application of organic EL elements to light sources such as electrophotographic copying machines or printers, or light emission is expected. When an organic EL element is used for light emission, the organic EL element has surface emission, has high color rendering properties, and has an advantage that light control is easy. Furthermore, fluorescent lamps contain mercury, but organic EL elements do not contain mercury, and there are many advantages such as that the organic EL elements do not contain ultraviolet rays.
　Ｃ．Ｗ．Ｔａｎｇらによる低電圧駆動の有機ＥＬ素子の報告（非特許文献１）がなされて以来、有機ＥＬ素子に関する研究が盛んに行われている。有機ＥＬ素子は、電圧を印加することにより、陽極より注入された正孔と陰極より注入された電子との再結合によってエネルギーが生じる。有機ＥＬ素子は、当該エネルギーによって発光層が発光する原理を利用した自発光素子である。しかしながら、有機ＥＬ素子は、再結合によって生じたエネルギーの８０％以上を熱として放出してしまう。有機ＥＬ素子中の温度が上昇すると、素子を構成する有機化合物に変質等が生じ、発光の寿命が短くなってしまうという問題がある。また、有機ＥＬ素子は、温度の上昇に伴って、電流の流れが指数関数的に良くなる。したがって、有機ＥＬ素子に部分的な温度上昇が生じると、その部分に電流が集中してしまい、部分的な発光強度の増加による輝度のむらが生じてしまう。さらに温度上昇が続くと、最終的には有機ＥＬ素子の劣化または破壊による輝度のむらを引き起こしてしまう。 C. W. Since Tang et al. Reported on low-voltage driven organic EL elements (Non-patent Document 1), research on organic EL elements has been actively conducted. In the organic EL element, when a voltage is applied, energy is generated by recombination of holes injected from the anode and electrons injected from the cathode. The organic EL element is a self-luminous element utilizing the principle that the light emitting layer emits light by the energy. However, the organic EL element releases 80% or more of the energy generated by recombination as heat. When the temperature in the organic EL device rises, there is a problem that the organic compound constituting the device is altered and the life of light emission is shortened. In addition, in the organic EL element, the current flow increases exponentially as the temperature rises. Therefore, when a partial temperature rise occurs in the organic EL element, the current concentrates in that portion, resulting in uneven brightness due to a partial increase in emission intensity. If the temperature continues to rise further, the luminance unevenness due to deterioration or destruction of the organic EL element will be finally caused.
　そこで、特許文献１～４では、有機ＥＬ素子の熱を放出する工夫が開示されている。特許文献１に開示されている有機ＥＬ素子では、基板が光透過性を有するサファイア、または石英等、通常のソーダガラスに比べ熱伝導率が高い材料で形成されている。この構成によれば、有機ＥＬ素子から発生する熱を透明基板を通じて周囲空気中に効果的に放熱することができ、かつ耐湿対策も十分に行うことが可能となり、有機ＥＬ素子の特性の劣化を改善できる。 Therefore, Patent Documents 1 to 4 disclose a device for releasing the heat of the organic EL element. In the organic EL element disclosed in Patent Document 1, the substrate is formed of a material having higher thermal conductivity than ordinary soda glass, such as sapphire or quartz having light transmittance. According to this configuration, the heat generated from the organic EL element can be effectively radiated to the ambient air through the transparent substrate, and it is possible to sufficiently take measures against moisture, thereby deteriorating the characteristics of the organic EL element. Can improve.
　また、特許文献２に開示されている有機ＥＬ素子では、有機ＥＬ素子とペルチェ素子の吸熱側との熱抵抗が、有機ＥＬ素子とペルチェ素子の放熱側との熱抵抗よりも小さいように設定されている。そして、有機ＥＬ素子が駆動されて発光する際に、ペルチェ素子を同時に駆動させると、有機ＥＬ素子の発光に伴って発生する熱がペルチェ素子の作用により積極的にペルチェ素子の放熱側に移動されて有機ＥＬ素子が冷却される。これにより、有機ＥＬ素子の輝度を低下させずに寿命を向上させることができる。 In the organic EL element disclosed in Patent Document 2, the thermal resistance between the organic EL element and the heat absorption side of the Peltier element is set to be smaller than the thermal resistance between the organic EL element and the heat dissipation side of the Peltier element. ing. When the organic EL element is driven to emit light, if the Peltier element is driven at the same time, the heat generated by the light emission of the organic EL element is positively transferred to the heat dissipation side of the Peltier element by the action of the Peltier element. Thus, the organic EL element is cooled. Thereby, lifetime can be improved, without reducing the brightness | luminance of an organic EL element.
　特許文献３に開示されている有機ＥＬ素子には、有機ＥＬ素子を封止するための封止基板の熱を外部に放熱するための放熱手段が形成されている。放熱手段としては、例えば、放熱フィン、ヒートパイプ、またはペルチェ素子等が使用できる。これにより、有機ＥＬ素子の発熱を外部に放熱することにより、発光層の温度を下げ、発熱に伴う発光層の劣化を防止することができる。 In the organic EL element disclosed in Patent Document 3, a heat radiating means for radiating the heat of the sealing substrate for sealing the organic EL element to the outside is formed. As the heat dissipating means, for example, heat dissipating fins, heat pipes, Peltier elements or the like can be used. Thereby, by radiating the heat generated by the organic EL element to the outside, the temperature of the light emitting layer can be lowered, and the deterioration of the light emitting layer due to the heat generation can be prevented.
　一方、特許文献４には、有機ＥＬ素子の発光面とは反対側に伝熱層が設けられている構成が開示されている。当該伝熱層は、有機ＥＬ素子の発光に伴って生成した熱を外部への放熱を促進する層である。この構成によれば、長時間連続駆動時の有機ＥＬ素子の温度上昇が防止され、耐久性の強い有機ＥＬ素子が得られる。 On the other hand, Patent Document 4 discloses a configuration in which a heat transfer layer is provided on the side opposite to the light emitting surface of the organic EL element. The said heat-transfer layer is a layer which accelerates | stimulates the heat | fever produced | generated with the light emission of the organic EL element to the exterior. According to this structure, the temperature rise of the organic EL element at the time of continuous driving for a long time is prevented, and a highly durable organic EL element can be obtained.
日本国公開特許公報「特開平１０－１４４４６８（１９９８年５月２９日公開）」Japanese Patent Publication “JP 10-144468 (published May 29, 1998)” 日本国公開特許公報「特開２００４－２９６１００（２００４年１０月２１日公開）」Japanese Patent Publication “Japanese Patent Laid-Open No. 2004-296100 (published on October 21, 2004)” 日本国公開特許公報「特開２００５－１４９８５３（２００５年６月９日公開）」Japanese Patent Publication “Japanese Patent Laid-Open No. 2005-149853 (published on June 9, 2005)” 日本国公開特許公報「特開２００８－３１１０７６（２００８年１２月２５日公開）」Japanese Patent Publication “JP 2008-311076 (released on Dec. 25, 2008)”
　上記した特許文献１～４では、有機ＥＬ素子の発光による発熱を放熱する技術が開示されているが、いずれも発熱を抑えるのには不十分であったり、または発熱を抑えられても耐久性が低下してしまったり等、問題が生じてしまう。 In Patent Documents 1 to 4 described above, technologies for dissipating heat generated by light emission of the organic EL element are disclosed. However, any of these techniques is insufficient to suppress heat generation or durability even if heat generation is suppressed. This causes problems such as a decrease in the number of times.
　具体的には、特許文献１に開示されている有機ＥＬ素子では、有機ＥＬ素子の光透過性を考慮し、高価であるが、サファイアまたは石英等を用いている。しかし、サファイアを用いた場合でも、熱伝導率は４６Ｗ／（ｍ・Ｋ）と高値である。サファイアよりも熱伝導率が高い材料は高価であり、なおかつ光透過性が低いため、ほとんど使用できない。したがって、本文献に開示されている有機ＥＬ素子は、その放熱性に限度がある。 Specifically, the organic EL element disclosed in Patent Document 1 is expensive in consideration of the light transmittance of the organic EL element, but sapphire or quartz is used. However, even when sapphire is used, the thermal conductivity is as high as 46 W / (m · K). A material having a higher thermal conductivity than sapphire is expensive and has a low light transmission, so it can hardly be used. Therefore, the organic EL element disclosed in this document has a limit in heat dissipation.
　一方、特許文献２に開示されている有機ＥＬ素子では、有機ＥＬ素子を冷却することができるが、有機ＥＬ素子用の電極とペルチェ素子用の電極とをそれぞれ用意しなければならない。そのため、製造コストが高くなってしまう。さらには、本文献に開示されている有機ＥＬ素子は、該表面がパッシベーション膜によって覆われている。一般的に、有機ＥＬ素子は酸素または水分に非常に弱いため、大気中に有機ＥＬ素子を放置すると、酸素または水蒸気の有機ＥＬ素子内への進入による劣化が引き起こされる。そのため、本文献に開示されている有機ＥＬ素子には、その保護膜として、パッシベーション膜によって覆っている。しかしながら、パッシベーション膜だけでは、酸素または水分を遮断することができないため、有機ＥＬ素子が劣化してしまう。 On the other hand, in the organic EL element disclosed in Patent Document 2, the organic EL element can be cooled, but an electrode for the organic EL element and an electrode for the Peltier element must be prepared. Therefore, the manufacturing cost is increased. Furthermore, the surface of the organic EL element disclosed in this document is covered with a passivation film. In general, an organic EL element is very sensitive to oxygen or moisture. Therefore, when the organic EL element is left in the atmosphere, deterioration due to the entry of oxygen or water vapor into the organic EL element is caused. Therefore, the organic EL element disclosed in this document is covered with a passivation film as a protective film. However, since only the passivation film cannot block oxygen or moisture, the organic EL element deteriorates.
　また、特許文献３に開示されている有機ＥＬ素子には、封止基板の外側に放熱フィン、ヒートパイプ、またはペルチェ素子等の放熱手段を形成している。したがって、有機ＥＬ素子の発光によって生じた熱を、封止基板を介して放熱しているため、冷却効率が悪くなる。 Further, in the organic EL element disclosed in Patent Document 3, heat radiation means such as a heat radiation fin, a heat pipe, or a Peltier element is formed outside the sealing substrate. Therefore, since the heat generated by the light emission of the organic EL element is dissipated through the sealing substrate, the cooling efficiency is deteriorated.
　さらに、特許文献４には、有機ＥＬ素子の発光面とは反対側に伝熱層が設けられている構成が開示されている。当該伝熱層は、有機ＥＬ素子を作成した後に、蒸着重合によって熱伝導性ポリマーを伝熱層として形成している。この際、有機ＥＬ素子上への熱伝導性ポリマーの蒸着によって、有機ＥＬ素子がダメージを受けて発光性能が低下する場合がある。 Furthermore, Patent Document 4 discloses a configuration in which a heat transfer layer is provided on the side opposite to the light emitting surface of the organic EL element. The heat transfer layer is formed by forming a thermally conductive polymer as a heat transfer layer by vapor deposition polymerization after an organic EL element is formed. At this time, there is a case where the organic EL element is damaged by the vapor deposition of the heat conductive polymer on the organic EL element and the light emitting performance is lowered.
　本発明は、上記の問題に鑑みてなされたものであり、その目的は、連続駆動時の有機ＥＬ素子の発熱を効率的に取り除くことができる発光装置、および当該発光装置の製造方法の製造方法、ならびに該発光装置を備えた有機エレクトロルミネッセンス表示装置を提供することにある。 The present invention has been made in view of the above problems, and an object of the present invention is to provide a light-emitting device that can efficiently remove the heat generated by the organic EL element during continuous driving, and a method for manufacturing the light-emitting device. And an organic electroluminescence display device including the light-emitting device.
　本発明に係る発光装置は、上記の課題を解決するために、
　少なくとも第一電極、発光層および第二電極を順次積層して成る有機エレクトロルミネッセンス素子を、少なくとも１つ搭載した発光装置であって、
　前記発光層からの光を取り出す光取り出し側に形成された第一外部基板と、
　前記第一電極および第二電極のうち前記光取り出し側の反対側に形成されている電極に接し、かつ当該電極の仕事関数よりも大きい仕事関数を有する導電層と、
　前記第一外部基板に対向して配置され、かつ前記第一外部基板と共に前記有機エレクトロルミネッセンス素子を封止する第二外部基板と、
　前記第二外部基板に形成され、一端が前記導電層に接続されるとともに、他端が前記第一外部基板および前記第二外部基板によって封止された領域の外部に伸び、かつ前記導電層の仕事関数以上の仕事関数を有する基板上配線と、
　前記基板上配線の他端に形成され、当該基板上配線の仕事関数よりも小さい仕事関数を有し、かつ放熱構造を有する外部導電層とを備えていることを特徴としている。 In order to solve the above problems, a light-emitting device according to the present invention provides
A light-emitting device having at least one organic electroluminescence element formed by sequentially laminating at least a first electrode, a light-emitting layer, and a second electrode,
A first external substrate formed on the light extraction side for extracting light from the light emitting layer;
A conductive layer in contact with an electrode formed on the opposite side of the light extraction side of the first electrode and the second electrode, and having a work function larger than the work function of the electrode;
A second external substrate disposed opposite the first external substrate and encapsulating the organic electroluminescence element together with the first external substrate;
Formed on the second external substrate, having one end connected to the conductive layer, the other end extending outside the region sealed by the first external substrate and the second external substrate, and the conductive layer Wiring on the substrate having a work function equal to or higher than the work function;
And an external conductive layer formed at the other end of the wiring on the substrate, having a work function smaller than that of the wiring on the substrate, and having a heat dissipation structure.
　一般に、有機ＥＬ素子に電圧を印加すると、その発光層の発光に伴い有機ＥＬ素子が発熱してしまう。有機ＥＬ素子中の温度が上昇すると、電流の流れが指数関数的に良くなる。したがって、有機ＥＬ素子に部分的な温度上昇が生じると、その部分に電流が集中してしまい、部分的な発光強度の増加による輝度のむらが生じてしまう。 Generally, when a voltage is applied to an organic EL element, the organic EL element generates heat as the light emitting layer emits light. As the temperature in the organic EL element rises, the current flow improves exponentially. Therefore, when a partial temperature rise occurs in the organic EL element, the current concentrates in that portion, resulting in uneven brightness due to a partial increase in emission intensity.
　ここで、上記の構成によれば、本発明の発光装置においては、有機エレクトロルミネッセンス素子（以下有機ＥＬ素子とも表記）を駆動するための第一電極および第二電極のうち、光取り出し側の電極に、当該電極の仕事関数よりも大きい仕事関数を有する導電層が接している。したがって、当該電極と当該導電層とはペルチェ素子を構成する。また、両者は互いに直列に接続されているので、有機ＥＬ素子を駆動すべく電極に電圧を印加すると、同時にペルチェ素子も駆動される結果となる。 Here, according to the above configuration, in the light emitting device of the present invention, the light extraction side electrode among the first electrode and the second electrode for driving the organic electroluminescence element (hereinafter also referred to as organic EL element). Further, a conductive layer having a work function larger than that of the electrode is in contact with the conductive layer. Therefore, the electrode and the conductive layer constitute a Peltier element. In addition, since both are connected in series with each other, when a voltage is applied to the electrode to drive the organic EL element, the Peltier element is also driven at the same time.
　このとき有機ＥＬ素子において発生した熱は、光取り出し側の電極から、より仕事関数の大きい導電層に吸熱される（ペルチェ効果）。さらに、当該電極が吸熱した熱は、基板上配線に第一配線に伝熱する。ここで、基板上配線の他端部には、基板上配線の仕事関数よりも小さい仕事関数を有する外部導電層が形成されているため、基板上配線の熱は外部導電層に伝熱される。そして、外部導電層が有する放熱構造によって、外部導電層の熱が放熱される。 At this time, heat generated in the organic EL element is absorbed by the conductive layer having a higher work function from the electrode on the light extraction side (Peltier effect). Further, the heat absorbed by the electrode is transferred to the first wiring to the wiring on the substrate. Here, since the external conductive layer having a work function smaller than the work function of the wiring on the substrate is formed at the other end of the wiring on the substrate, the heat of the wiring on the substrate is transferred to the external conductive layer. The heat of the external conductive layer is radiated by the heat dissipation structure of the external conductive layer.
　このようにして、有機ＥＬ素子の発光層から生じた熱は、導電層によって吸熱され、さらに導電層が吸熱した熱は外部導電層によって放熱される。以上のように、本発明によれば、連続して駆動した時の有機ＥＬ素子の発熱を効率的に取り除くことができる発光装置を提供することができる。 Thus, the heat generated from the light emitting layer of the organic EL element is absorbed by the conductive layer, and the heat absorbed by the conductive layer is dissipated by the external conductive layer. As described above, according to the present invention, it is possible to provide a light-emitting device that can efficiently remove the heat generated by the organic EL element when continuously driven.
　さらに、本発明の発光装置では、有機ＥＬ素子において発生した部分的な温度上昇を、効率的に除去できるので、発光輝度を均一化することができる。また、ペルチェ素子と有機ＥＬ素子とが直列に接続されているため、共通の電源によって両者を駆動できる。また、本発明に係る発光装置は、２枚の外部基板によって挟まれて封止されているので、大気中に放置しても、酸素および水分が有機ＥＬ素子内に入り込むのを防ぐことができる。 Furthermore, in the light emitting device of the present invention, the partial temperature rise generated in the organic EL element can be efficiently removed, so that the light emission luminance can be made uniform. Further, since the Peltier element and the organic EL element are connected in series, both can be driven by a common power source. In addition, since the light-emitting device according to the present invention is sandwiched and sealed between two external substrates, oxygen and moisture can be prevented from entering the organic EL element even when left in the atmosphere. .
　本発明に係る発光装置の製造方法は、上記の課題を解決するために、
　基板上に少なくとも第一電極、発光層および第二電極を、前記第一電極、前記発光層、および前記第二電極の順に形成することによって、有機エレクトロルミネッセンス素子を形成する工程と、
　前記有機エレクトロルミネッセンス素子を少なくとも１つ用意する工程と、
　前記第二電極上に、当該第二電極の仕事関数よりも大きい仕事関数を有する導電層を形成する工程と、
　前記基板の下面に第一外部基板を当接する工程と、
　前記導電層の仕事関数以上の仕事関数を有する基板上配線が形成された第二外部基板を、当該基板上配線の一端を前記導電層に接続させるように前記第一外部基板に対向して配置することによって、前記有機エレクトロルミネッセンス素子を封止する工程と、
　前記基板上配線の仕事関数よりも小さい仕事関数を有し、かつ放熱構造を有する外部導電層を、前記第一外部基板および前記第二外部基板によって封止された領域の外部に伸びた前記基板上配線の他端に設ける工程とを含むことを特徴としている。 In order to solve the above problems, a method for manufacturing a light emitting device according to the present invention is as follows.
Forming an organic electroluminescent element by forming at least a first electrode, a light emitting layer, and a second electrode on the substrate in the order of the first electrode, the light emitting layer, and the second electrode;
Preparing at least one organic electroluminescence element;
Forming a conductive layer having a work function larger than the work function of the second electrode on the second electrode;
Contacting the first external substrate to the lower surface of the substrate;
A second external substrate on which a wiring on the substrate having a work function equal to or higher than the work function of the conductive layer is formed so as to face the first external substrate so that one end of the wiring on the substrate is connected to the conductive layer. A step of sealing the organic electroluminescence element,
The substrate having an external conductive layer having a work function smaller than a work function of the wiring on the substrate and having a heat dissipation structure extended outside a region sealed by the first external substrate and the second external substrate And a step of providing at the other end of the upper wiring.
　上記の構成によれば、高い放熱作用を有するボトムエミッション型の発光装置を提供することができる。 According to the above configuration, it is possible to provide a bottom emission type light emitting device having a high heat dissipation action.
　本発明に係る発光装置の製造方法は、上記の課題を解決するために、
　基板上に少なくとも第一電極、発光層、第二電極および前記第一電極の仕事関数よりも大きい仕事関数を有する導電層を、前記導電層、前記第一電極、前記発光層、および前記第二電極の順に形成することによって、前記導電層を備えた有機エレクトロルミネッセンス素子を形成する工程と、
　前記有機エレクトロルミネッセンス素子を少なくとも１つ用意する工程と、
　前記第二電極の上面に第一外部基板を当接する工程と、
　前記導電層の仕事関数以上の仕事関数を有する基板上配線が形成された第二外部基板を、当該基板上配線の一端を前記導電層に接続させるように前記第一外部基板に対向して配置することによって、前記有機エレクトロルミネッセンス素子を封止する工程と、
　前記基板上配線の仕事関数よりも小さい仕事関数を有し、かつ放熱構造を有する外部導電層を、前記第一外部基板および前記第二外部基板によって封止された領域の外部に伸びた前記基板上配線の端部に設ける工程とを含むことを特徴としている。 In order to solve the above problems, a method for manufacturing a light emitting device according to the present invention is as follows.
A conductive layer having a work function larger than that of at least the first electrode, the light emitting layer, the second electrode, and the first electrode on the substrate, the conductive layer, the first electrode, the light emitting layer, and the second Forming an organic electroluminescence element including the conductive layer by forming the electrodes in order, and
Preparing at least one organic electroluminescence element;
Contacting the first external substrate with the upper surface of the second electrode;
A second external substrate on which a wiring on the substrate having a work function equal to or higher than the work function of the conductive layer is formed so as to face the first external substrate so that one end of the wiring on the substrate is connected to the conductive layer. A step of sealing the organic electroluminescence element,
The substrate having an external conductive layer having a work function smaller than a work function of the wiring on the substrate and having a heat dissipation structure extended outside a region sealed by the first external substrate and the second external substrate And a step of providing at an end portion of the upper wiring.
　上記の構成によれば、高い放熱作用を有するトップエミッション型の発光装置を提供することができる。 According to the above configuration, it is possible to provide a top emission type light emitting device having a high heat dissipation action.
　本発明に係る有機エレクトロルミネッセンス表示装置は、上記の課題を解決するために、上述したいずれかの発光装置を備えていることを特徴としている。 The organic electroluminescence display device according to the present invention is characterized by including any of the light-emitting devices described above in order to solve the above-described problems.
　上記の構成によれば、有機ＥＬ素子の輝度のむらおよび有機ＥＬ素子の発熱を抑えた発光装置を搭載した有機ＥＬ表示装置を提供することができる。 According to the above configuration, it is possible to provide an organic EL display device equipped with a light emitting device that suppresses uneven luminance of the organic EL element and heat generation of the organic EL element.
　本発明の他の目的、特徴、および優れた点は、以下に示す記載によって十分分かるであろう。また、本発明の利点は、添付図面を参照した次の説明で明白になるであろう。 Other objects, features, and superior points of the present invention will be fully understood from the following description. The advantages of the present invention will become apparent from the following description with reference to the accompanying drawings.
　本発明に係る発光装置によれば、導電層によってペルチェ効果が誘起され、その部分での吸熱量も高くなる。その結果、輝度を均一化することができる。さらに、導電層に加え、放熱構造を有する外部導電層を備えていることによって、有機ＥＬ素子の発熱をより効率的に取り除くことができる。 According to the light emitting device of the present invention, the Peltier effect is induced by the conductive layer, and the amount of heat absorbed at that portion also increases. As a result, the luminance can be made uniform. Furthermore, by providing an external conductive layer having a heat dissipation structure in addition to the conductive layer, the heat generation of the organic EL element can be more efficiently removed.
　また、本発明に係る発光装置は、２枚の外部基板によって挟まれて封止されているので、大気中に放置しても、酸素および水分が有機ＥＬ素子内に入り込むのを防ぐことができる。以上より、本発明に係る発光装置では、連続して駆動した時の有機ＥＬ素子の発熱を効率的に取り除くことができ、なおかつ耐久性の強い有機ＥＬ素子を提供することができる。 In addition, since the light-emitting device according to the present invention is sandwiched and sealed between two external substrates, oxygen and moisture can be prevented from entering the organic EL element even when left in the atmosphere. . As described above, in the light emitting device according to the present invention, it is possible to efficiently remove the heat generated from the organic EL element when continuously driven, and to provide a highly durable organic EL element.
本発明の一実施形態に係る発光装置（ボトムエミッション型）の断面を示す図である。It is a figure which shows the cross section of the light-emitting device (bottom emission type) which concerns on one Embodiment of this invention. 本発明の一実施形態に係る有機エレクトロルミネッセンス素子の短辺方向の断面を示す図である。It is a figure which shows the cross section of the short side direction of the organic electroluminescent element which concerns on one Embodiment of this invention. 本発明の一実施形態に係る有機エレクトロルミネッセンス素子の長辺方向の断面を示す図である。It is a figure which shows the cross section of the long side direction of the organic electroluminescent element which concerns on one Embodiment of this invention. 本発明の一実施形態に係る発光装置（トップエミッション型）の断面を示す図である。It is a figure which shows the cross section of the light-emitting device (top emission type) which concerns on one Embodiment of this invention.
　（発光装置２０の概要）
　本実施形態に係る発光装置２０の概要について、図１を参照して説明する。図１は、本実施形態に係る発光装置２０の断面を示す図である。 (Outline of the light emitting device 20)
An outline of the light emitting device 20 according to the present embodiment will be described with reference to FIG. FIG. 1 is a view showing a cross section of a light emitting device 20 according to the present embodiment.
　発光装置２０は、基板２上に形成された有機ＥＬ素子１５（有機エレクトロルミネッセンス素子）を、互いに対向する２枚の外部基板１，８によって挟んで封止した構成をしている。具体的には、図１に示すように、基板２上には、陽極３（第一電極、第二電極）、陰極５（第一電極、第二電極）および有機層４（発光層）の順にそれぞれ形成されている。陰極５上には、吸熱作用を示す導電層６が形成されており、導電層６のさらに上には外部基板８（第一外部基板、第二外部基板）が形成されている。基板２の下には、外部基板１（第一外部基板、第二外部基板）が形成されている。 The light emitting device 20 has a configuration in which an organic EL element 15 (organic electroluminescence element) formed on a substrate 2 is sandwiched and sealed between two external substrates 1 and 8 facing each other. Specifically, as shown in FIG. 1, an anode 3 (first electrode, second electrode), a cathode 5 (first electrode, second electrode), and an organic layer 4 (light emitting layer) are formed on a substrate 2. Each is formed in order. A conductive layer 6 exhibiting an endothermic effect is formed on the cathode 5, and an external substrate 8 (a first external substrate and a second external substrate) is formed on the conductive layer 6. Under the substrate 2, an external substrate 1 (first external substrate, second external substrate) is formed.
　導電層６は、配線７ａ（基板上配線）の一端に接続されている。配線７ａは、外部基板１および外部基板８によって封止された領域の外部に伸びている。そして、配線７ａの他端には、放熱構造を有する外部導電層９が接続されており、当該外部導電層９には引出配線１１ｂが接続されている。一方、基板２および陽極３は、導電部１０を介して、外部基板８に形成された配線７ｂと接続されている。当該配線７ｂには、引出配線１１ａが接続されている。 The conductive layer 6 is connected to one end of the wiring 7a (wiring on the substrate). The wiring 7 a extends outside a region sealed by the external substrate 1 and the external substrate 8. An external conductive layer 9 having a heat dissipation structure is connected to the other end of the wiring 7a, and a lead wiring 11b is connected to the external conductive layer 9. On the other hand, the substrate 2 and the anode 3 are connected to the wiring 7 b formed on the external substrate 8 through the conductive portion 10. The lead wiring 11a is connected to the wiring 7b.
　この構成によれば、有機ＥＬ素子１５と導電層６とが直列に接続されている。したがって、有機ＥＬ素子１５を駆動すると、導電層６も同時に駆動する構成になっている。これによって、有機ＥＬ素子１５が発した熱を導電層６が吸熱し、さらに導電層６が吸熱した熱を外部導電層９が放熱することができる。この詳しいメカニズムは、後ほど説明する。 According to this configuration, the organic EL element 15 and the conductive layer 6 are connected in series. Therefore, when the organic EL element 15 is driven, the conductive layer 6 is also driven at the same time. As a result, the heat generated by the organic EL element 15 is absorbed by the conductive layer 6, and the heat absorbed by the conductive layer 6 can be dissipated by the external conductive layer 9. This detailed mechanism will be explained later.
　（吸熱および放熱のメカニズム）
　有機ＥＬ素子１５に電圧を印加すると、陽極３から正孔が注入され、陰極５から電子が注入される。有機層４は発光層を有しており、注入された正孔および電子は、有機層４の発光層において再結合し、エネルギ－を生じる。生じたエネルギーを利用して、発光層は発光するが、生じたエネルギーの８０％以上は熱として放出されてしまう。そのため、発光に伴う有機ＥＬ素子１５の発熱によって、素子中の温度が上昇すると、素子を構成する有機化合物に変質等が生じ、発光の寿命が短くなってしまうという問題がある。また、有機ＥＬ素子１５は、温度の上昇に伴って、電流の流れが指数関数的に良くなる。したがって、有機ＥＬ素子１５に部分的な温度上昇が生じると、その部分に電流が集中してしまい、部分的な発光強度の増加による輝度のむらが生じてしまう。 (Mechanism of heat absorption and heat dissipation)
When a voltage is applied to the organic EL element 15, holes are injected from the anode 3 and electrons are injected from the cathode 5. The organic layer 4 has a light emitting layer, and the injected holes and electrons recombine in the light emitting layer of the organic layer 4 to generate energy. The light emitting layer emits light using the generated energy, but 80% or more of the generated energy is released as heat. Therefore, when the temperature in the element rises due to heat generation of the organic EL element 15 due to light emission, there is a problem that the organic compound constituting the element is altered and the life of light emission is shortened. In the organic EL element 15, the current flow increases exponentially as the temperature rises. Therefore, when a partial temperature rise occurs in the organic EL element 15, the current concentrates in that portion, resulting in uneven brightness due to a partial increase in light emission intensity.
　そこで、本実施形態に係る発光装置２０は、有機ＥＬ素子１５の温度上昇を防ぐために、導電層６および外部導電層９によって、有機ＥＬ素子１５が発した熱を吸熱し、放熱している。その詳しいメカニズムについて説明する。 Therefore, the light-emitting device 20 according to the present embodiment absorbs the heat generated by the organic EL element 15 by the conductive layer 6 and the external conductive layer 9 and dissipates it in order to prevent the temperature of the organic EL element 15 from rising. The detailed mechanism will be described.
　前述したように、導電層６は陰極５の上に形成されており、当該導電層６と外部導電層９とは配線７ａを介して接続されている。さらに、外部導電層９は、ヒートシンクまたは放熱フィンを有しており、放熱構造を有している。この際、導電層６には、陰極５よりも仕事関数が大きい導電性材料を用いる。また、配線７ａには、導電層６の仕事関数以上の仕事関数を有する導電性材料を用いる。さらに、外部導電層９には、配線７ａよりも仕事関数が小さい導電性材料を用いる。この構成によれば、有機ＥＬ素子１５の発光層で生じた熱は陰極５に伝熱するが、陰極５よりも導電層６の方が大きい仕事関数を有しているため、陰極５の熱は導電層６に吸熱される。さらに、配線７ａは導電層６の仕事関数以上の仕事関数を有しているため、導電層６の熱は配線７ａに吸熱される。これらは、２種類の金属の接合部に電流を流すと、片方の金属からもう片方の金属へ熱が移動する効果（ペルチェ効果）を利用している。さらに、配線７ａよりも外部導電層９の方が小さい仕事関数を有しているため、配線７ａの熱は外部導電層９に伝熱される。そして、外部導電層９が有する放熱構造によって、外部導電層９の熱が放熱される。このようにして、有機ＥＬ素子１５の発光層から生じた熱は、導電層６によって吸熱され、さらに導電層６が吸熱した熱は外部導電層９によって放熱される。 As described above, the conductive layer 6 is formed on the cathode 5, and the conductive layer 6 and the external conductive layer 9 are connected via the wiring 7a. Further, the external conductive layer 9 has a heat sink or a heat radiating fin, and has a heat radiating structure. At this time, a conductive material having a work function larger than that of the cathode 5 is used for the conductive layer 6. For the wiring 7a, a conductive material having a work function higher than that of the conductive layer 6 is used. Further, a conductive material having a work function smaller than that of the wiring 7a is used for the external conductive layer 9. According to this configuration, the heat generated in the light emitting layer of the organic EL element 15 is transferred to the cathode 5. However, since the conductive layer 6 has a larger work function than the cathode 5, Is absorbed by the conductive layer 6. Furthermore, since the wiring 7a has a work function higher than that of the conductive layer 6, the heat of the conductive layer 6 is absorbed by the wiring 7a. These utilize the effect (Peltier effect) in which heat is transferred from one metal to the other when a current is passed through the joint between the two types of metal. Furthermore, since the external conductive layer 9 has a smaller work function than the wiring 7 a, the heat of the wiring 7 a is transferred to the external conductive layer 9. The heat of the external conductive layer 9 is radiated by the heat dissipation structure of the external conductive layer 9. Thus, the heat generated from the light emitting layer of the organic EL element 15 is absorbed by the conductive layer 6, and the heat absorbed by the conductive layer 6 is dissipated by the external conductive layer 9.
　前述したように、輝度にむらがある有機ＥＬ素子１５において、輝度の明るい部分では温度上昇が大きい。温度が上昇することにより、さらに電流値が高くなるが、本実施形態に係る発光装置２０によれば、導電層６によってペルチェ効果が誘起され、その部分での吸熱量も高くなる。その結果、輝度を均一化することができる。さらに、導電層６に加え、放熱構造を有する外部導電層９を備えていることによって、有機ＥＬ素子１５の発熱をより効率的に取り除くことができる。 As described above, in the organic EL element 15 having uneven luminance, the temperature rise is large in the bright portion. As the temperature rises, the current value is further increased. However, according to the light emitting device 20 according to the present embodiment, the Peltier effect is induced by the conductive layer 6, and the heat absorption amount at that portion also increases. As a result, the luminance can be made uniform. Furthermore, by providing the external conductive layer 9 having a heat dissipation structure in addition to the conductive layer 6, the heat generation of the organic EL element 15 can be more efficiently removed.
　なお、導電層６は複数層設けても良い。この場合には、上層（配線７ａ側）になるほど仕事関数が大きい導電性材料を用いる必要がある。また、陰極５が外部基板１上に形成され、陽極３が外部基板８の下に形成されている構造の場合には、導電層６は陰極５と外部基板１との間に設ける。 Note that a plurality of conductive layers 6 may be provided. In this case, it is necessary to use a conductive material having a higher work function as it becomes an upper layer (wiring 7a side). When the cathode 5 is formed on the external substrate 1 and the anode 3 is formed below the external substrate 8, the conductive layer 6 is provided between the cathode 5 and the external substrate 1.
　（有機ＥＬ素子１５の構成）
　本実施形態に係る発光装置２０の有機ＥＬ素子１５の詳しい構成について、図２および図３を参照して説明する。図２は、有機ＥＬ素子１５の短辺方向の断面を示す図である。図３は、有機ＥＬ素子１５の長辺方向の断面を示す図である。 (Configuration of organic EL element 15)
A detailed configuration of the organic EL element 15 of the light emitting device 20 according to the present embodiment will be described with reference to FIGS. FIG. 2 is a view showing a cross section of the organic EL element 15 in the short side direction. FIG. 3 is a diagram showing a cross section of the organic EL element 15 in the long side direction.
　本実施形態に係る有機ＥＬ素子１５は、図２に示すように、基板２上に陽極３、有機層４および陰極５を順次積層して構成されており、有機層４は、少なくとも発光層４ｃを含んでいる。ただし、有機層４は発光層４ｃ以外に他の層を含んでいても良い。また、各層はいずれも１層である必要はなく、多層構造を有していても良い。例えば、以下のような構成も可能である。
（１）陽極／正孔輸送層／発光層／電子輸送層／陰極
（２）陽極／正孔注入層／正孔輸送層／発光層／電子輸送層／電子注入層／陰極
（３）陽極／正孔注入層／正孔輸送層／電子ブロッキング層／発光層／正孔ブロッキング層／電子注入層／陰極
　図３では、陽極３／正孔注入層４ａ／正孔輸送層４ｂ／発光層４ｃ／電子ブロッキング層４ｄ／電子輸送層４ｅ／陰極５を有した有機ＥＬ素子１５の断面を示している。正孔注入層４ａとは、陽極３から効率良く正孔を受け取り、発光層４ｃへ効率良く正孔を注入するための層である。正孔輸送層４ｂも同様に、陽極３から効率良く正孔を受け取り、発光層４ｃへ効率良く正孔を受け渡すための層である。一方、電子注入層は、陰極５から効率良く電子を受け取り、発光層４ｃへ効率良く電子を注入するための層である。電子輸送層４ｅも同様に、陰極５から効率良く電子を受け取り、発光層４ｃへ効率良く電子を受け渡すための層である。正孔ブロッキング層４ｄは、正孔が電子と再結合せずに陰極５へ抜けるのを妨害する層であり、電子ブロッキング層は、電子が正孔と再結合せずに陽極３へ抜けるのを妨害する層である。 As shown in FIG. 2, the organic EL element 15 according to the present embodiment is configured by sequentially laminating an anode 3, an organic layer 4, and a cathode 5 on a substrate 2, and the organic layer 4 includes at least a light emitting layer 4c. Is included. However, the organic layer 4 may include other layers in addition to the light emitting layer 4c. Each layer does not have to be a single layer and may have a multilayer structure. For example, the following configuration is also possible.
(1) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (2) Anode / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer / cathode (3) anode / Hole injection layer / hole transport layer / electron blocking layer / light emitting layer / hole blocking layer / electron injection layer / cathode In FIG. 3, anode 3 / hole injection layer 4a / hole transport layer 4b / light emitting layer 4c / The cross section of the organic EL element 15 which has the electron blocking layer 4d / electron carrying layer 4e / cathode 5 is shown. The hole injection layer 4a is a layer for efficiently receiving holes from the anode 3 and efficiently injecting holes into the light emitting layer 4c. Similarly, the hole transport layer 4b is a layer for efficiently receiving holes from the anode 3 and efficiently transferring holes to the light emitting layer 4c. On the other hand, the electron injection layer is a layer for efficiently receiving electrons from the cathode 5 and efficiently injecting electrons into the light emitting layer 4c. Similarly, the electron transport layer 4e is a layer that efficiently receives electrons from the cathode 5 and efficiently delivers electrons to the light emitting layer 4c. The hole blocking layer 4d is a layer that prevents holes from passing through the cathode 5 without recombining with electrons, and the electron blocking layer prevents electrons from passing through the anode 3 without recombining with holes. It is a blocking layer.
　なお、有機層４は電荷発生層を含む場合もある。電荷発生層とは、受光時に有機層４内を略等電位に保つとともに、一方の主表面より正孔を、他方の主表面より電子を注入する機能を持つ層である。したがって、電荷発生層を発光層４ｃの間に設ける等すれば、陰極５側に正孔を注入し、陽極側に電子を注入することによって、正孔と電子との再結合を誘起することができる。 The organic layer 4 may include a charge generation layer. The charge generation layer is a layer having a function of maintaining the inside of the organic layer 4 at a substantially equal potential when receiving light, and injecting holes from one main surface and electrons from the other main surface. Therefore, if a charge generation layer is provided between the light emitting layers 4c, recombination of holes and electrons can be induced by injecting holes into the cathode 5 and injecting electrons into the anode. it can.
　なお、本実施形態に係る有機ＥＬ素子１５では、発光層４ｃの光の取り出しは、陽極３側および陰極５側のいずれからでも良い。したがって、ボトムエミッション型、およびトップエミッション型のどちらでも良い。導電層６は、陽極３側および陰極５のうち、光取り出し側の反対側に形成されている電極に接するように形成される。 In the organic EL element 15 according to this embodiment, the light extraction from the light emitting layer 4c may be performed from either the anode 3 side or the cathode 5 side. Therefore, either a bottom emission type or a top emission type may be used. The conductive layer 6 is formed so as to be in contact with the electrode formed on the side opposite to the light extraction side among the anode 3 side and the cathode 5.
　（発光装置２０の基板２の概要）
　以下では、発光装置２０の各部材について詳細に説明する。まず、有機ＥＬ素子１５の基板２としては、ガラス基板、金属基板、またはフレキシブル基板等が用いられる。ただし、ロールツーロール法を用いる場合には、フレキシブル基板が好ましい。 (Outline of the substrate 2 of the light emitting device 20)
Below, each member of the light-emitting device 20 is demonstrated in detail. First, as the substrate 2 of the organic EL element 15, a glass substrate, a metal substrate, a flexible substrate, or the like is used. However, when using a roll-to-roll method, a flexible substrate is preferable.
　フレキシブル基板としてはＯＰＰ（延伸ポリプロピレン）、ＰＥＴ（ポリエチレンテレフタレート）、ＰＥＮ（ポリエチレンナフタレート）、またはＰＰＳ（ポリフェニレンサルファイト）等のプラスチックフィルム、石英ガラスフィルム、またはガラスとフィルムとを積層したフィルム等がある。なお、基板２としては、絶縁性を有し、光透過性が高い基板であることが好ましい。さらに、フィルム基板を用いる場合は、フィルム基板からのアルカリ酸化物の溶出を防ぐＳｉＯ２（酸化シリコン）膜等の保護膜を有していることがより好ましい。 Examples of flexible substrates include plastic films such as OPP (stretched polypropylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), or PPS (polyphenylene sulfite), quartz glass films, or a film in which glass and a film are laminated. is there. Note that the substrate 2 is preferably a substrate having insulating properties and high light transmittance. Furthermore, when using a film substrate, it is more preferable to have a protective film such as a SiO 2 (silicon oxide) film that prevents elution of alkali oxide from the film substrate.
　（発光装置２０の電極の概要）
　陽極３および陰極５として適用可能なものを以下に示す。陽極３には、発光層４ｃに正孔をより効率良く注入するために、仕事関数が高い金属から形成された金属電極を用いることが好ましい。例えば、Ａｕ（金）、Ａｇ（銀）、Ｐｔ（白金）、またはＮｉ（ニッケル）等である。また、陽極３側から発光層４ｃの光を取り出すために、透明電極を用いても良い。例えば、ＩＴＯ（酸化インジウムスズ）、ＩＤＩＸＯ（出光興産株式会社製の出光透明導電材料）、ＧＺＯ（ガリウム添加酸化亜鉛）、またはＳｎＯ２（酸化スズ）等の透明導電材料が挙げられる。 (Outline of electrode of light emitting device 20)
What can be applied as the anode 3 and the cathode 5 is shown below. For the anode 3, it is preferable to use a metal electrode formed of a metal having a high work function in order to inject holes into the light emitting layer 4c more efficiently. For example, Au (gold), Ag (silver), Pt (platinum), Ni (nickel), or the like. Further, a transparent electrode may be used to extract light from the light emitting layer 4c from the anode 3 side. Examples thereof include transparent conductive materials such as ITO (indium tin oxide), IDIXO (Idemitsu Kosan Co., Ltd., Idemitsu transparent conductive material), GZO (gallium-doped zinc oxide), or SnO 2 (tin oxide).
　一方、陰極５には、発光層４ｃに電子をより効率良く注入するために、仕事関数が低い金属と安定した金属とを積層した電極を用いることが好ましい。例えば積層する金属の組み合わせとして、Ｃａ（カルシウム）／Ａｌ（アルミニウム）、Ｃｅ（セリウム）／Ａｌ、Ｃｓ（セシウム）／Ａｌ、またはＢａ（バリウム）／Ａｌ等がある。また、仕事関数が低い金属を含有する電極を用いても良い。例えば、Ｃａ－Ａｌ合金（カルシウム－アルミニウム合金）、Ｍｇ－Ａｇ合金（マグネシウム－銀合金）、またはＬｉ－Ａｌ合金（リチウム－アルミニウム合金）等がある。絶縁層（薄膜）と金属電極とを組み合わせた電極を用いても良い。例えば、ＬｉＦ（フッ化リチウム）／Ａｌ、ＬｉＦ／Ｃａ／Ａｌ、ＢａＦ２（フッ化バリウム）／Ｂａ／Ａｌ、またはＬｉＦ／Ａｌ／Ａｇ等である。なお、上記陰極５の膜厚を５０ｎｍ以下の半透膜にすることによって、陰極５側から発光層４ｃの光を取り出すことも可能である。 On the other hand, in order to inject electrons into the light emitting layer 4c more efficiently, it is preferable to use an electrode in which a metal having a low work function and a stable metal are stacked. For example, there are Ca (calcium) / Al (aluminum), Ce (cerium) / Al, Cs (cesium) / Al, Ba (barium) / Al, etc. as a combination of metals to be laminated. Alternatively, an electrode containing a metal having a low work function may be used. For example, there are a Ca—Al alloy (calcium-aluminum alloy), a Mg—Ag alloy (magnesium-silver alloy), a Li—Al alloy (lithium-aluminum alloy), and the like. You may use the electrode which combined the insulating layer (thin film) and the metal electrode. For example, LiF (lithium fluoride) / Al, LiF / Ca / Al, BaF 2 (barium fluoride) / Ba / Al, or LiF / Al / Ag. In addition, it is also possible to take out the light of the light emitting layer 4c from the cathode 5 side by making the film thickness of the said cathode 5 into a semi-permeable film 50 nm or less.
　陽極３および陰極５の作製方法としては、蒸着法、ＥＢ（電子ビーム）法、ＭＢＥ（電子ビーム溶解）法、またはスパッタ法等のドライプロセス、またはスピンコート法、印刷法、またはインクジェット法等のウェットプロセスを用いることができる。 As a manufacturing method of the anode 3 and the cathode 5, a dry process such as a vapor deposition method, an EB (electron beam) method, an MBE (electron beam melting) method, or a sputtering method, a spin coating method, a printing method, an ink jet method, or the like is used. A wet process can be used.
　（発光装置２０の導電層６の概要）
　導電層６には、前述したように、陰極５よりも仕事関数が大きい導電性材料を用いる。導電層６の作製方法としては、陽極３および陰極５の作製方法と同様の方法用いることができる。導電材料の例として、Ａｕ（金）、Ａｇ（銀）、またはＩＴＯ（酸化インジウムスズ）等が挙げられる。 (Outline of the conductive layer 6 of the light emitting device 20)
As described above, a conductive material having a work function larger than that of the cathode 5 is used for the conductive layer 6. As a manufacturing method of the conductive layer 6, the same method as the manufacturing method of the anode 3 and the cathode 5 can be used. Examples of the conductive material include Au (gold), Ag (silver), ITO (indium tin oxide), and the like.
　（発光装置２０の正孔注入層４ａの概要）
　正孔注入層４ａでは、前述したように、陽極３から効率良く正孔を受け取り、発光層４ｃへ効率良く受け渡す。そのため、正孔注入層４ａには、陽極３の仕事関数と、発光層４ｃのＨＯＭＯ（最高被占準位）レベルとの間の仕事関数を有する材料であることが好ましい。例えば、無機ｐ型半導体材料、ポルフィリン化合物、ＴＰＤ（Ｎ，Ｎ’－ビス－（３－メチルフェニル）－Ｎ，Ｎ’－ビス－（フェニル）－ベンジジン）、またはＮＰＤ（Ｎ，Ｎ’－ジ（ナフタレン－１－イル）－Ｎ，Ｎ’－ジフェニル－ベンジジン）等の芳香族第三級アミン化合物、ヒドラゾン化合物、キナクリドン化合物、またはスチリルアミン化合物等の低分子材料、ＰＡＮＩ（ポリアニリン）、ＰＥＤＴ／ＰＳＳ（３，４－ポリエチレンジオキシチオフェン／ポリスチレンサルフォネイト）、Ｐｏｌｙ－ＴＰＤ（ポリ［トリフェニルアミン誘導体］）、またはＰＶＣｚ（ポリビニルカルバゾール）等の高分子材料、Ｐｒｅ－ＰＰＶ（ポリ（ｐ－フェニレンビニレン）前駆体）、またはＰｒｅ－ＰＮＶ（ポリ（ｐ－ナフタレンビニレン）前駆体）等の高分子材料前駆体等を用いることができる。これらは、有機ＥＬ装置、または有機光導電体に一般的に使用する正孔注入材料である。 (Outline of the hole injection layer 4a of the light emitting device 20)
In the hole injection layer 4a, as described above, holes are efficiently received from the anode 3 and efficiently transferred to the light emitting layer 4c. Therefore, the hole injection layer 4a is preferably a material having a work function between the work function of the anode 3 and the HOMO (highest occupied level) level of the light emitting layer 4c. For example, an inorganic p-type semiconductor material, a porphyrin compound, TPD (N, N′-bis- (3-methylphenyl) -N, N′-bis- (phenyl) -benzidine), or NPD (N, N′-diethyl) (Naphthalen-1-yl) -N, N′-diphenyl-benzidine) and other low molecular weight materials such as aromatic tertiary amine compounds, hydrazone compounds, quinacridone compounds, or styrylamine compounds, PANI (polyaniline), PEDT / Polymer materials such as PSS (3,4-polyethylenedioxythiophene / polystyrene sulfonate), Poly-TPD (poly [triphenylamine derivative]), or PVCz (polyvinylcarbazole), Pre-PPV (poly (p- Phenylene vinylene) precursor), or Pre-PNV (poly (p-naphthalene vinylene) precursor Polymer material precursors such as (body) can be used. These are hole injection materials commonly used in organic EL devices or organic photoconductors.
　正孔注入層４ａは、上記正孔注入材料を少なくとも１種類用いて直接蒸着法等のドライプロセスによって形成できる。なお、上記正孔注入材料を２種類以上使用して正孔注入層４ａを形成しても問題ない。この場合には、ドナーまたはアクセプター等の添加剤を含有していても良い。 The hole injection layer 4a can be formed by a dry process such as a direct vapor deposition method using at least one of the above hole injection materials. It should be noted that there is no problem even if the hole injection layer 4a is formed by using two or more kinds of the hole injection materials. In this case, an additive such as a donor or an acceptor may be contained.
　なお、正孔注入層４ａの別の形成方法として、上記正孔注入材料を少なくとも１種類溶媒に溶かした正孔注入層形成用塗液を用いたウェットプロセスがある。なお、正孔注入層形成用塗液は、上記正孔注入材料を２種類以上含有していても良い。また、正孔注入層形成用塗液は、結着用の樹脂、レベリング剤、または添加剤等を含有していても良い。結着用樹脂としては、例えば、ポリカーボネート、またはポリエステル等を用いることができる。また、添加剤としては、ドナーまたはアクセプター等を使用できる。正孔注入層形成用塗液の溶媒としては、上記正孔注入材料を溶解、または分散できる溶剤であれば良い。例えば、純水、メタノール、エタノール、ＴＨＦ（テトラヒドロフラン）、クロロホルム、キシレン、またはトリメチルベンゼン等を用いることができる。 As another method for forming the hole injection layer 4a, there is a wet process using a coating liquid for forming a hole injection layer in which the hole injection material is dissolved in at least one kind of solvent. The hole injection layer forming coating solution may contain two or more of the above hole injection materials. The hole injection layer forming coating solution may contain a binding resin, a leveling agent, an additive, or the like. As the binding resin, for example, polycarbonate or polyester can be used. Moreover, a donor or an acceptor etc. can be used as an additive. The solvent for the hole injection layer forming coating solution may be any solvent that can dissolve or disperse the hole injection material. For example, pure water, methanol, ethanol, THF (tetrahydrofuran), chloroform, xylene, trimethylbenzene, or the like can be used.
　（発光装置２０の正孔輸送層４ｂの概要）
　正孔輸送層４ｂでは、前述したように、正孔注入層４ａから効率良く正孔を受け取り、発光層４ｃへ効率良く受け渡す。そのため、正孔輸送層４ｂには、正孔注入層４ａのＨＯＭＯレベルと、発光層４ｃのＨＯＭＯレベルとの間の仕事関数を有する材料を用いることが好ましい。これによって、正孔をより効率よく発光層４ｃに注入・輸送でき、有機ＥＬ素子１５の電圧を低減、または有機ＥＬ素子１５の発光効率を高めることができる。さらに、発光層４ｃからの電子の漏れを防止し、発光層４ｃでの発光効率を高めるために、正孔輸送層４ｂのＬＵＭＯレベルを発光層４ｃのＬＵＭＯレベルよりも低くすることが好ましい。また、発光層４ｃ中に励起子を閉じ込めるために、正孔輸送層４ｂのバンドギャップを発光層４ｃのバンドギャップよりも大きくすることが好ましい。正孔輸送材料の例として、Ｎ，Ｎ’－ビス（３－メチルフェニル）－Ｎ，Ｎ’－ビス（フェニル）－ベンジジン（ＴＰＤ）、またはＮ，Ｎ’－ジ（ナフタレン－１－イル）－Ｎ，Ｎ’－ジフェニル－ベンジジン（ＮＰＤ）等の芳香族第三級アミン化合物等が挙げられる。 (Outline of the hole transport layer 4b of the light emitting device 20)
As described above, in the hole transport layer 4b, holes are efficiently received from the hole injection layer 4a and are efficiently transferred to the light emitting layer 4c. Therefore, it is preferable to use a material having a work function between the HOMO level of the hole injection layer 4a and the HOMO level of the light emitting layer 4c for the hole transport layer 4b. Thereby, holes can be injected and transported to the light emitting layer 4c more efficiently, and the voltage of the organic EL element 15 can be reduced or the light emission efficiency of the organic EL element 15 can be increased. Furthermore, in order to prevent leakage of electrons from the light emitting layer 4c and increase the light emission efficiency in the light emitting layer 4c, it is preferable to make the LUMO level of the hole transport layer 4b lower than the LUMO level of the light emitting layer 4c. Moreover, in order to confine excitons in the light emitting layer 4c, it is preferable that the band gap of the hole transport layer 4b is larger than the band gap of the light emitting layer 4c. Examples of hole transport materials include N, N′-bis (3-methylphenyl) -N, N′-bis (phenyl) -benzidine (TPD), or N, N′-di (naphthalen-1-yl) And aromatic tertiary amine compounds such as —N, N′-diphenyl-benzidine (NPD).
　正孔輸送層４ｂは、上記条件を満たす正孔輸送材料を少なくとも１種類用いて直接蒸着法等のドライプロセスによって形成できる。なお、上記条件を満たす正孔輸送材料を２種類以上用いて正孔輸送層４ｂを形成しても問題ない。この場合には、ドナーまたはアクセプター等の添加剤を含有していても良い。 The hole transport layer 4b can be formed by a dry process such as a direct vapor deposition method using at least one hole transport material satisfying the above conditions. Note that there is no problem even if the hole transport layer 4b is formed by using two or more hole transport materials satisfying the above conditions. In this case, an additive such as a donor or an acceptor may be contained.
　なお、正孔輸送層４ｂの別の形成方法として、上記条件を満たす正孔輸送材料を少なくとも１種類溶媒に溶かした正孔輸送層形成用塗液を用いたウェットプロセスがある。なお、正孔輸送層形成用塗液は、上記条件を満たす正孔輸送材料を２種類以上含有していても良い。また、正孔輸送層形成用塗液は、結着用の樹脂、レベリング剤、または添加剤等を含有していても良い。結着用樹脂としては、例えば、ポリカーボネート、ポリエステル等を用いることができる。また、添加剤としては、ドナーまたはアクセプター等を使用できる。正孔輸送層形成用塗液の溶媒としては、正孔輸送材料を溶解、または分散できる溶剤であれば良い。例えば、純水、メタノール、エタノール、ＴＨＦ、クロロホルム、キシレン、またはトリメチルベンゼン等を用いることができる。 As another method for forming the hole transport layer 4b, there is a wet process using a hole transport layer forming coating solution in which a hole transport material satisfying the above conditions is dissolved in at least one kind of solvent. In addition, the coating liquid for hole transport layer formation may contain 2 or more types of hole transport materials which satisfy | fill the said conditions. In addition, the hole transport layer forming coating solution may contain a binding resin, a leveling agent, or an additive. As the binding resin, for example, polycarbonate, polyester or the like can be used. Moreover, a donor or an acceptor etc. can be used as an additive. The solvent for the coating liquid for forming the hole transport layer may be any solvent that can dissolve or disperse the hole transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
　（発光装置２０の電子ブロッキング層の概要）
　電子ブロッキング層には、上記正孔注入材料と同様の材料を用いることが可能である。ただし、電子ブロッキング層には、該ＬＵＭＯ（最低空準位）レベルの絶対値が、電子ブロッキング層と接する正孔注入層４ａのＬＵＭＯレベルの絶対値よりも小さくなる材料を用いるのが良い。これより、電子をより効率よく、発光層４ｃに閉じ込めることができる。 (Outline of electron blocking layer of light emitting device 20)
For the electron blocking layer, the same material as the hole injection material can be used. However, for the electron blocking layer, it is preferable to use a material in which the absolute value of the LUMO (lowest vacancy level) level is smaller than the absolute value of the LUMO level of the hole injection layer 4a in contact with the electron blocking layer. Thus, electrons can be confined more efficiently in the light emitting layer 4c.
　電気ブロッキング層は、上記条件を満たす電子ブロッキング材料を少なくとも１種類用いて直接蒸着法等のドライプロセスによって形成できる。なお、電子ブロッキング層は、上記条件を満たす電子ブロッキング材料を２種類以上用いて電子ブロッキング層を形成しても問題ない。 The electrical blocking layer can be formed by a dry process such as a direct vapor deposition method using at least one type of electron blocking material that satisfies the above conditions. In addition, even if an electron blocking layer forms an electron blocking layer using two or more types of electron blocking materials which satisfy | fill the said conditions, it is satisfactory.
　なお、電子ブロッキング層の別の形成方法として、上記条件を満たす電子ブロッキング材料を少なくとも１種類溶媒に溶かした電子ブロッキング層形成用塗液を用いたウェットプロセスがある。なお、電子ブロッキング層形成用塗液は、上記条件を満たす電子ブロッキング材料を２種類以上含有していても良い。また、電子ブロッキング層形成用塗液は、結着用の樹脂、レベリング剤、または添加剤等を含有していても良い。結着用樹脂としては、例えば、ポリカーボネート、ポリエステル等を用いることができる。また、添加剤としては、ドナーまたはアクセプター等を使用できる。電子ブロッキング層形成用塗液の溶媒としては、正孔輸送材料を溶解、または分散できる溶剤であれば良い。例えば、純水、メタノール、エタノール、ＴＨＦ、クロロホルム、キシレン、またはトリメチルベンゼン等を用いることができる。 As another method for forming the electron blocking layer, there is a wet process using a coating liquid for forming an electron blocking layer in which an electron blocking material satisfying the above conditions is dissolved in at least one solvent. In addition, the coating liquid for electron blocking layer formation may contain 2 or more types of electron blocking materials which satisfy | fill the said conditions. The coating solution for forming an electron blocking layer may contain a binding resin, a leveling agent, or an additive. As the binding resin, for example, polycarbonate, polyester or the like can be used. Moreover, a donor or an acceptor etc. can be used as an additive. The solvent for the electron blocking layer-forming coating solution may be any solvent that can dissolve or disperse the hole transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
　（発光装置２０の発光層４ｃの概要）
　発光層４ｃとしては、有機ＥＬ装置に一般的に使用する発光材料を用いることができるが、それ以外にも、例えば、低分子発光材料、高分子発光材料、または高分子発光材料の前駆体等も利用できる。低分子発光材料とは、例えば、ＤＰＶＢｉ（４，４’－ビス（２，２’－ジフェニルビニル）－ビフェニル）等の芳香族ジメチリデェン化合物、５－メチル－２－［２－［４－（５－メチル－２－ベンゾオキサゾリル）フェニル］ビニル］ベンゾオキサゾール等のオキサジアゾール化合物、ＴＡＺ（３－（４－ビフェニルイル）－４－フェニル－５－ｔ－ブチルフェニル－１，２，４－トリアゾール）等のトリアゾール誘導体、１，４－ビス（２－メチルスチリル）ベンゼン等のスチリルベンゼン化合物、チオピラジンジオキシド誘導体、ベンゾキノン誘導体、ナフトキノン誘導体、アントラキノン誘導体、ジフェノキノン誘導体、またはフルオレノン誘導体等の蛍光性有機材料、アゾメチン亜鉛錯体、またはＡｌｑ３（（８－ヒドロキシキノリナト）アルミニウム錯体）等の蛍光性有機金属化合物等である。一方、高分子発光材料とは、ポリ（２－デシルオキシ－１，４－フェニレン）ＤＯ－ＰＰＰ、ＰＰＰ－ＮＥｔ３ ＋（ポリ［２，５－ビス－［２－（Ｎ，Ｎ，Ｎ－トリエチルアンモニウム）エトキシ］－１，４－フェニル－アルト－１，４－フェニルレン］ジブロマイド）、ＭＥＨ－ＰＰＶ（ポリ［２－（２’－エチルヘキシルオキシ）－５－メトキシ－１，４－フェニレンビニレン］）、ＭＰＳ－ＰＰＶ（ポリ［５－メトキシ－（２－プロパノキシサルフォニド）－１，４－フェニレンビニレン］）、ＣＮ－ＰＰＶ（ポリ［２，５－ビス－（ヘキシルオキシ）－１，４－フェニレン－（１－シアノビニレン）］）、ＰＤＡＦ（ポリ（９，９－ジオクチルフルオレン））、またはポリスピロ等がある。また、高分子発光材料の前駆体としては、ＰＰＶ前駆体、ＰＮＶ前駆体、またはＰＰＰ前駆体等が挙げられる。 (Outline of the light emitting layer 4c of the light emitting device 20)
As the light emitting layer 4c, a light emitting material generally used in an organic EL device can be used. In addition, for example, a low molecular light emitting material, a polymer light emitting material, or a precursor of a polymer light emitting material is used. Can also be used. Examples of the low-molecular light emitting material include aromatic dimethylidene compounds such as DPVBi (4,4′-bis (2,2′-diphenylvinyl) -biphenyl), 5-methyl-2- [2- [4- (5 Oxadiazole compounds such as -methyl-2-benzoxazolyl) phenyl] vinyl] benzoxazole, TAZ (3- (4-biphenylyl) -4-phenyl-5-t-butylphenyl-1,2,4 -Triazole derivatives such as triazole), styrylbenzene compounds such as 1,4-bis (2-methylstyryl) benzene, thiopyrazine dioxide derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, diphenoquinone derivatives, or fluorenone derivatives Organic material, azomethine zinc complex, or Alq 3 ((8-hydroxyquino Fluorescent organic metal compounds such as linato) aluminum complex). On the other hand, polymer light-emitting materials include poly (2-decyloxy-1,4-phenylene) DO-PPP, PPP-NEt 3 + (poly [2,5-bis- [2- (N, N, N-triethyl). Ammonium) ethoxy] -1,4-phenyl-alt-1,4-phenyllene] dibromide), MEH-PPV (poly [2- (2′-ethylhexyloxy) -5-methoxy-1,4-phenylenevinylene) ], MPS-PPV (poly [5-methoxy- (2-propanoxysulfonide) -1,4-phenylenevinylene]), CN-PPV (poly [2,5-bis- (hexyloxy) -1 , 4-phenylene- (1-cyanovinylene)]), PDAF (poly (9,9-dioctylfluorene)), or polyspiro. Further, examples of the precursor of the polymer light emitting material include a PPV precursor, a PNV precursor, a PPP precursor, and the like.
　発光層４ｃは、その種類によってある特定の色を発光するが、発光装置２０には、異なる色を発光する発光層４ｃを複数組み合わせて設けても良い。例えば、青色の発光層４ｃと、緑色の発光層４ｃと、赤色の発光層４ｃとを組み合わせることによって、白色に発光する発光装置２０にすることも可能である。 The light emitting layer 4c emits a specific color depending on its type, but the light emitting device 20 may be provided with a combination of a plurality of light emitting layers 4c that emit different colors. For example, a light emitting device 20 that emits white light can be obtained by combining a blue light emitting layer 4c, a green light emitting layer 4c, and a red light emitting layer 4c.
　発光層４ｃは、上記発光材料を少なくとも１種類用いて形成できる。なお、上記発光材料を２種類以上用いて形成しても問題ない。また、発光層４ｃには、発光材料の代わりに少なくとも１種類の正孔輸送材料、または電子輸送材料を用いても良い。この場合には、２種類以上の正孔輸送材料、または電子輸送材料を用いても問題ない。 The light emitting layer 4c can be formed using at least one of the above light emitting materials. Note that there is no problem even if two or more kinds of the light emitting materials are used. Further, for the light emitting layer 4c, at least one kind of hole transport material or electron transport material may be used instead of the light emitting material. In this case, there is no problem even if two or more hole transport materials or electron transport materials are used.
　発光層４ｃは、少なくとも発光材料、正孔輸送材料、または電子輸送材料を用いて直接蒸着法等のドライプロセスによって形成できる。また、発光層４ｃの別の形成方法として、少なくとも発光材料、正孔輸送材料、または電子輸送材料を溶媒に溶かした発光層４ｃ形成用塗液を用いたウェットプロセスもある。なお、発光層４ｃ形成用塗液は、２種類以上の発光材料、正孔輸送材料、または電子輸送材料を含有していても良い。また、発光層４ｃ形成用塗液は、結着用の樹脂、レベリング剤、または添加剤等を含有していても良い。結着用樹脂としては、例えば、ポリカーボネート、ポリエステル等を用いることができる。また、添加剤としては、ドナーまたはアクセプター等を使用できる。発光層４ｃ形成用塗液の溶媒としては、発光材料、正孔輸送材料、または電子輸送材料を溶解、または分散できる溶剤であれば良い。例えば、純水、メタノール、エタノール、ＴＨＦ、クロロホルム、キシレン、またはトリメチルベンゼン等を用いることができる。なお、発光層４ｃの正孔輸送材料は、正孔輸送層４ｂに用いる正孔輸送材料と同様の材料を用いることができる。また、発光層４ｃの電子輸送材料は、電子輸送層４ｅに用いる電子輸送材料と同様の材料を用いることができる。 The light emitting layer 4c can be formed by a dry process such as a direct vapor deposition method using at least a light emitting material, a hole transport material, or an electron transport material. As another method for forming the light emitting layer 4c, there is a wet process using a coating solution for forming the light emitting layer 4c in which at least a light emitting material, a hole transport material, or an electron transport material is dissolved in a solvent. The coating liquid for forming the light emitting layer 4c may contain two or more kinds of light emitting materials, hole transport materials, or electron transport materials. Moreover, the coating liquid for forming the light emitting layer 4c may contain a binding resin, a leveling agent, an additive, or the like. As the binding resin, for example, polycarbonate, polyester or the like can be used. Moreover, a donor or an acceptor etc. can be used as an additive. The solvent for the coating solution for forming the light emitting layer 4c may be any solvent that can dissolve or disperse the light emitting material, the hole transport material, or the electron transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used. In addition, the hole transport material of the light emitting layer 4c can use the material similar to the hole transport material used for the hole transport layer 4b. Further, as the electron transport material of the light emitting layer 4c, the same material as the electron transport material used for the electron transport layer 4e can be used.
　（発光装置２０の正孔ブロッキング層４ｄの概要）
　正孔ブロッキング層４ｄには、下記電子輸送材料と同様の材料を用いることが可能である。ただし、正孔ブロッキング層には、電子を輸送する機能を有し、なおかつ正孔を輸送する能力が著しく小さい材料を用いるのが好ましい。これより、正孔を発光層４ｃにより効率良く閉じ込めることができる。 (Outline of the hole blocking layer 4d of the light emitting device 20)
For the hole blocking layer 4d, the same material as the following electron transport material can be used. However, it is preferable to use a material having a function of transporting electrons and a very small ability to transport holes for the hole blocking layer. Accordingly, holes can be efficiently confined by the light emitting layer 4c.
　正孔ブロッキング材料の例としては、２，９－ジメチル－４，７－ジフェニル－１，１０－フェナントロリン（ＢＣＰ）、またはビス（２－メチル－８－キノリノラート）（ｐ－フェニルフェノラート）アルミニウム（ＩＩＩ）（ＢＡｌｑ）等が挙げられる。 Examples of hole blocking materials include 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), or bis (2-methyl-8-quinolinolate) (p-phenylphenolate) aluminum ( III) (BAlq) and the like.
　正孔ブロッキング層４ｄを形成する際には、発光層４ｃと電子輸送層４ｅとの間に、例えばＢＣＰを用いて真空蒸着法によって厚さ１０ｎｍ程度の正孔ブロッキング層４ｄを形成することができる。 When the hole blocking layer 4d is formed, the hole blocking layer 4d having a thickness of about 10 nm can be formed between the light emitting layer 4c and the electron transport layer 4e by, for example, BCP using a vacuum deposition method. .
　（発光装置２０の電子輸送層４ｅの概要）
　電子輸送層４ｅは、前述したように、電子注入層から効率良く電子を受け取り、発光層４ｃへ効率良く受け渡す。そのため、電子注入層のＬＵＭＯレベルと、発光層４ｃのＬＵＭＯレベルとの間のＬＵＭＯレベルを有する材料を用いることが好ましい。これによって、電子をより効率良く発光層４ｃに注入・輸送でき、有機ＥＬ素子１５の電圧を低減、または、発光効率を高めることができる。さらに、発光層４ｃからの電子の漏れを防止し、発光層４ｃでの発光効率を高めるために、電子輸送層４ｅのＨＯＭＯレベルを発光層４ｃのＨＯＭＯレベルよりも高くすることが好ましい。また、発光層４ｃ中に励起子を閉じ込めるために、電子輸送層４ｅのバンドギャップを発光層４ｃのバンドギャップよりも大きくすることが好ましい。電子輸送材料の例として、ｎ型半導体である無機材料、オキサジアゾール誘導体、トリアゾール誘導体、チオピラジンジオキシド誘導体、ベンゾキノン誘導体、ナフトキノン誘導体、アントラキノン誘導体、ジフェノキノン誘導体、またはフルオレノン誘導体等の低分子材料、Ｐｏｌｙ－ＯＸＺ（ポリ（オキサジアゾール））、またはＰＳＳ（ポリスチレン誘導体）等の高分子材料等が挙げられる。 (Outline of the electron transport layer 4e of the light emitting device 20)
As described above, the electron transport layer 4e efficiently receives electrons from the electron injection layer and efficiently delivers them to the light emitting layer 4c. Therefore, it is preferable to use a material having a LUMO level between the LUMO level of the electron injection layer and the LUMO level of the light emitting layer 4c. Thereby, electrons can be injected and transported to the light emitting layer 4c more efficiently, and the voltage of the organic EL element 15 can be reduced or the light emission efficiency can be increased. Furthermore, in order to prevent leakage of electrons from the light emitting layer 4c and increase the light emission efficiency in the light emitting layer 4c, it is preferable to set the HOMO level of the electron transport layer 4e higher than the HOMO level of the light emitting layer 4c. Further, in order to confine excitons in the light emitting layer 4c, it is preferable that the band gap of the electron transport layer 4e is larger than the band gap of the light emitting layer 4c. Examples of electron transport materials include inorganic materials that are n-type semiconductors, low molecular weight materials such as oxadiazole derivatives, triazole derivatives, thiopyrazine dioxide derivatives, benzoquinone derivatives, naphthoquinone derivatives, anthraquinone derivatives, diphenoquinone derivatives, or fluorenone derivatives, Examples thereof include a polymer material such as Poly-OXZ (poly (oxadiazole)) or PSS (polystyrene derivative).
　電子輸送層４ｅは、上記電子輸送材料を少なくとも１種類用いて直接蒸着法等のドライプロセスによって形成できる。なお、上記電子輸送層４ｅを２種類以上用いて電子輸送層４ｅを形成しても問題ない。この場合には、ドナーまたはアクセプター等の添加剤を含有していても良い。 The electron transport layer 4e can be formed by a dry process such as a direct vapor deposition method using at least one of the above electron transport materials. Note that there is no problem even if the electron transport layer 4e is formed by using two or more kinds of the electron transport layer 4e. In this case, an additive such as a donor or an acceptor may be contained.
　なお、電子輸送層４ｅの別の形成方法として、上記電子輸送材料を少なくとも１種類溶媒に溶かした電子輸送層形成用塗液を用いたウェットプロセスがある。なお、電子輸送層形成用塗液は、上記電子輸送材料を２種類以上含有していても良い。また、電子輸送層形成用塗液は、結着用の樹脂、レベリング剤、または添加剤等を含有していても良い。結着用樹脂としては、例えば、ポリカーボネート、ポリエステル等を用いることができる。また、添加剤としては、ドナーまたはアクセプター等を使用できる。電子輸送層形成用塗液の溶媒としては、電子輸送材料を溶解、または分散できる溶剤であれば良い。例えば、純水、メタノール、エタノール、ＴＨＦ、クロロホルム、キシレン、またはトリメチルベンゼン等を用いることができる。 As another method for forming the electron transport layer 4e, there is a wet process using a coating liquid for forming an electron transport layer in which the electron transport material is dissolved in at least one kind of solvent. In addition, the coating liquid for electron transport layer formation may contain the said electron transport material 2 or more types. The coating liquid for forming an electron transport layer may contain a binding resin, a leveling agent, or an additive. As the binding resin, for example, polycarbonate, polyester or the like can be used. Moreover, a donor or an acceptor etc. can be used as an additive. The solvent for the electron transport layer forming coating solution may be any solvent that can dissolve or disperse the electron transport material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
　（発光装置２０の電子注入層の概要）
　電子注入層には、電子の注入・輸送をより効率良く行うために、電子輸送層４ｅよりもＬＵＭＯのエネルギー準位が高い材料を用いることが好ましい。さらには、電子輸送材料よりも電子の移動速度が低い材料を用いることが好ましい。電子注入材料の例として、ＬｉＦ（フッ化リチウム）、またはＢａＦ２（フッ化バリウム）等のフッ化物、あるいはＬｉ２Ｏ（酸化リチウム）等の酸化物等が挙げられる。 (Outline of electron injection layer of light emitting device 20)
For the electron injection layer, it is preferable to use a material having a higher LUMO energy level than the electron transport layer 4e in order to perform electron injection / transport more efficiently. Furthermore, it is preferable to use a material whose electron moving speed is lower than that of the electron transporting material. Examples of the electron injection material include fluorides such as LiF (lithium fluoride) or BaF 2 (barium fluoride), and oxides such as Li 2 O (lithium oxide).
　（発光装置２０の電荷発生層の概要）
　電荷発生層は、前述したように、受光時に有機層４を略等電位に保つとともに、一方の主表面より正孔を、他方の主表面より電子を注入する機能をもつ。電荷発生層には、一方の面が正孔注入性を有しており、かつ他方の面が電子注入性を有しているものを使用する。例えば、Ｍｇ（マグネシウム）、Ａｇ、Ａｌ、Ｍｇ－Ａｇ合金、Ｍｇ－Ａｌ合金（マグネシウム－アルミニウム合金）、またはＡｌ－Ｌｉ合金等の薄膜金属、ＩＴＯ、またはＩＺＯ（酸化インジウム亜鉛）などの透明電極、オキレンの金属錯体または含Ｎ素環化合物等の電子輸送性化合物、アルカリ金属、アルカリ土類金属、または希土類金属、あるいはこれらを含有する化合物等から成る電子注入性化合物の混合層等がある。さらには、２－ＴＮＡＴＡ（４，４’，４”－トリス［Ｎ，Ｎ－（２－ナフチル）フェニルアミノ］トリフェニルアミン）、またはＮＰＤ等の正孔輸送性材料にＴＣＮＱ（７，７，８，８－テトラシアノ－ｐ－キノジメタン）、ＦｅＣｌ３（塩化鉄（ＩＩＩ））等の電子吸引性酸化剤をドープしたもの、ｐ型導電性高分子、またはｐ型半導体等から成る正孔導電性有機層、ｐ型α－Ｓｉ、ｐ型Ｓｉ、ｐ型ＣｄＴｅ、またはｐ型ＣｕＯ等のｐ型半導体、またはｎ型α－Ｓｉ、ｎ型Ｓｉ、ｎ型ＣｄＳ、またはｎ型ＺｎＳ等のｎ型半導体、あるいはこれらを組み合わせたｐ型またはｎ型の導電性高分子等も利用できる。当該導電性高分子の例として、ポリアリーレンビニレン、またはポリチェニレンビニレン等が挙げられる。 (Outline of the charge generation layer of the light emitting device 20)
As described above, the charge generation layer has a function of maintaining the organic layer 4 at a substantially equipotential during light reception and injecting holes from one main surface and electrons from the other main surface. As the charge generation layer, one having one surface having hole injection properties and the other surface having electron injection properties is used. For example, transparent electrodes such as Mg (magnesium), Ag, Al, Mg—Ag alloy, Mg—Al alloy (magnesium-aluminum alloy), thin film metal such as Al—Li alloy, ITO, or IZO (indium zinc oxide) And an electron injecting compound such as an electron transporting compound such as an oxylene metal complex or an N-containing ring compound, an alkali metal, an alkaline earth metal, a rare earth metal, or a compound containing these. Further, TCNQ (7,7,4) is added to a hole transporting material such as 2-TNATA (4,4 ′, 4 ″ -tris [N, N- (2-naphthyl) phenylamino] triphenylamine) or NPD. Hole conductivity made of an electron-withdrawing oxidizing agent such as 8,8-tetracyano-p-quinodimethane), FeCl 3 (iron (III) chloride), p-type conductive polymer, or p-type semiconductor Organic layer, p-type semiconductor such as p-type α-Si, p-type Si, p-type CdTe, or p-type CuO, or n-type such as n-type α-Si, n-type Si, n-type CdS, or n-type ZnS A semiconductor, or a p-type or n-type conductive polymer in combination of these can also be used, and examples of the conductive polymer include polyarylene vinylene and polychenylene vinylene.
　電荷発生層は、上記電荷発生材料を少なくとも１種類用いて直接蒸着法等のドライプロセスによって形成できる。なお、上記電荷発生材料を２種類以上用いて電荷発生層を形成しても問題ない。電荷発生層は、導電性、半導電性、または電気絶縁性を有するものでも良い。 The charge generation layer can be formed by a dry process such as a direct vapor deposition method using at least one of the above charge generation materials. Note that there is no problem even if the charge generation layer is formed by using two or more kinds of the charge generation materials. The charge generation layer may be conductive, semiconductive, or electrically insulating.
　電荷発生層の別の形成方法として、上記電荷発生材料を少なくとも１種類溶媒に溶かした電荷発生層形成用塗液を用いたウェットプロセスがある。なお、電荷発生層形成用塗液は、上記電荷発生送材料を２種類以上含有していても良い。また、電荷発生層形成用塗液は、結着用の樹脂、レベリング剤、または添加剤等を含有していても良い。結着用樹脂としては、例えば、ポリカーボネート、ポリエステル等を用いることができる。また、添加剤としては、ドナーまたはアクセプター等を使用できる。電荷発生層形成用塗液の溶媒としては、電荷発生材料を溶解、または分散できる溶剤であれば良い。例えば、純水、メタノール、エタノール、ＴＨＦ、クロロホルム、キシレン、またはトリメチルベンゼン等を用いることができる。 As another method of forming the charge generation layer, there is a wet process using a charge generation layer forming coating solution in which the above charge generation material is dissolved in at least one kind of solvent. In addition, the coating liquid for charge generation layer formation may contain two or more kinds of the above-described charge generation / transport materials. The coating solution for forming the charge generation layer may contain a binding resin, a leveling agent, an additive, or the like. As the binding resin, for example, polycarbonate, polyester or the like can be used. Moreover, a donor or an acceptor etc. can be used as an additive. The solvent for the charge generation layer forming coating solution may be any solvent that can dissolve or disperse the charge generation material. For example, pure water, methanol, ethanol, THF, chloroform, xylene, trimethylbenzene, or the like can be used.
　（発光装置２０の外部基板１，８の概要）
　有機ＥＬ素子１５を挟む２枚の外部基板１，８では、２枚のうち少なくともいずれかが光透過性を有していれば良い。したがって、少なくとも発光装置２０の光取り出し側の基板が透明であれば良い。例えば、ガラス、樹脂、または金属基板等を用いることができる。一方、有機ＥＬ素子１５を封止する側の基板には、従来から封止に用いられているガラス、樹脂、または金属基板等を用いることができるが、放熱効率を考慮すると熱伝導率の高いアルミニウムまたはステンレス等の金属基板、あるいはセラミックスが好ましい。さらにその外側には、放射率の高いグラファイト等を配置することがより好ましい。なお、外部基板１，８は、平面または曲面でも良く、屈曲部を有していても良い。 (Outline of the external substrates 1 and 8 of the light emitting device 20)
In the two external substrates 1 and 8 sandwiching the organic EL element 15, at least one of the two substrates may be light transmissive. Therefore, it is sufficient that at least the substrate on the light extraction side of the light emitting device 20 is transparent. For example, glass, resin, a metal substrate, or the like can be used. On the other hand, a glass, resin, metal substrate or the like conventionally used for sealing can be used for the substrate on the side where the organic EL element 15 is sealed. However, in consideration of heat dissipation efficiency, the thermal conductivity is high. A metal substrate such as aluminum or stainless steel, or ceramics is preferred. Further, it is more preferable to arrange graphite or the like having a high emissivity on the outside thereof. The external substrates 1 and 8 may be flat or curved and may have a bent portion.
　なお、有機ＥＬ素子１５を封止する側の基板の封止方法は、例えば、熱硬化樹脂またはＵＶ硬化樹脂によって貼り合わせる方法、またはガラス融着法などを用いることができる。また、ガラスまたは金属等で封止する際には、不活性ガス中に酸化カルシウム等の吸湿剤等を混入する方法を用いることができる。このように、有機ＥＬ素子１５および電極を封止することによって、外部からの酸素、および水分が発光装置２０内に混入するのを防止できるので、発光装置２０の寿命を向上できる。 In addition, the sealing method of the board | substrate on the side which seals the organic EL element 15 can use the method of bonding together with a thermosetting resin or UV curable resin, or a glass fusion method, for example. Moreover, when sealing with glass or a metal etc., the method of mixing moisture absorbents, such as a calcium oxide, in inert gas can be used. Thus, by sealing the organic EL element 15 and the electrode, it is possible to prevent external oxygen and moisture from being mixed into the light emitting device 20, so that the lifetime of the light emitting device 20 can be improved.
　以上では、各有機層４の形成方法として、真空蒸着法等のドライプロセスを示したが、ドクターブレード法、ディップコート法、マイクログラビア法、スプレー法、インクジェット法、または印刷法等のウェットプロセスを用いることができる。ウェットプロセスを用いて有機層４を形成する場合には、有機層４における吸湿および有機材料の変質を考えると、有機層４を不活性ガス、または真空中で形成することが好ましい。また、有機層４を形成した後に、残留溶媒を除去するために加熱乾燥を行うことが好ましい。加熱乾燥は、有機材料の変質を防止する観点で、不活性ガス中で行うことが好ましい。さらに、より効果的に残留溶剤を除去するためには、加熱乾燥を減圧下で行うことが好ましい。 In the above, a dry process such as a vacuum deposition method has been shown as a method for forming each organic layer 4, but a wet process such as a doctor blade method, a dip coating method, a micro gravure method, a spray method, an ink jet method, or a printing method is used. Can be used. In the case of forming the organic layer 4 using a wet process, it is preferable to form the organic layer 4 in an inert gas or vacuum in consideration of moisture absorption in the organic layer 4 and alteration of the organic material. Moreover, after forming the organic layer 4, it is preferable to heat-dry in order to remove a residual solvent. The heat drying is preferably performed in an inert gas from the viewpoint of preventing deterioration of the organic material. Furthermore, in order to remove the residual solvent more effectively, it is preferable to perform heat drying under reduced pressure.
　（発光装置２０の製造方法）
　本実施形態に係る発光装置２０の製造方法について説明する。 (Manufacturing method of the light-emitting device 20)
A method for manufacturing the light emitting device 20 according to the present embodiment will be described.
　まず、発光装置２０に搭載する有機ＥＬ素子１５を形成する。本実施形態に係る有機ＥＬ素子１５は、ロールツーロール法によって形成されることが好ましい。その手順としては、まず予め陽極３が形成してある基板２をロールツーロール蒸着装置にセットする。その後、セットした基板２を一定の速度で搬送する。搬送されてきた基板２の陽極３上に、各有機層４および陰極５を順番に形成し、帯状の有機ＥＬ素子１５を形成する。有機ＥＬ素子１５の陰極５の上に、陰極５よりも大きい仕事関数を有する導電層６を形成し、再びロール状に巻き取る。このようにして、導電層６を有する帯状の有機ＥＬ素子１５ができ上がる。この際、各有機層４、陰極５および導電層６を形成する時の蒸着速度を制御することによって、各層を所望の膜厚に仕上げることができる。 First, the organic EL element 15 to be mounted on the light emitting device 20 is formed. The organic EL element 15 according to this embodiment is preferably formed by a roll-to-roll method. As the procedure, first, the substrate 2 on which the anode 3 is previously formed is set in a roll-to-roll vapor deposition apparatus. Thereafter, the set substrate 2 is transported at a constant speed. Each organic layer 4 and cathode 5 are formed in order on the anode 3 of the substrate 2 that has been transported, and a strip-shaped organic EL element 15 is formed. A conductive layer 6 having a work function larger than that of the cathode 5 is formed on the cathode 5 of the organic EL element 15 and is wound up again in a roll shape. In this way, a strip-shaped organic EL element 15 having the conductive layer 6 is completed. At this time, each layer can be finished to a desired film thickness by controlling the vapor deposition rate when forming each organic layer 4, cathode 5 and conductive layer 6.
　なお、有機ＥＬ素子１５を形成した後、外部からの水分等によるダメージ、またはロールを巻き取る際の物理的な接触による傷等のダメージを防止するために、保護膜を形成しても良い。また、有機ＥＬ素子１５の表面に保護膜を貼り合わせてからロール状に巻き取らせても良い。なお、保護膜としては、Ａｌ、Ａｇ等の金属薄膜、フタロシアニン等の有機膜、またはＳｉＯＮ（酸窒化シリコン）、ＳｉＯ（一酸化シリコン）、ＳｉＮ（窒化シリコン）等の無機膜等が挙げられる。 Note that after the organic EL element 15 is formed, a protective film may be formed in order to prevent damage such as damage due to moisture from the outside or scratches due to physical contact when winding the roll. Alternatively, a protective film may be attached to the surface of the organic EL element 15 and then wound in a roll shape. Examples of the protective film include metal thin films such as Al and Ag, organic films such as phthalocyanine, or inorganic films such as SiON (silicon oxynitride), SiO (silicon monoxide), and SiN (silicon nitride).
　保護膜の形成方法は、ＥＢ蒸着法、スパッタリング法、イオンプレーティング法、または抵抗加熱蒸着法等が挙げられる。また、保護層としては、Ａｌ、Ａｇ等の金属薄膜、フタロシアニン等の有機膜、ＳｉＯＮ、ＳｉＯ、ＳｉＮ等の無機膜が挙げられる。その形成方法としては、ＥＢ蒸着法、スパッタリング法、イオンプレーティング法、または抵抗加熱蒸着法等がある。 Examples of the method for forming the protective film include EB vapor deposition, sputtering, ion plating, and resistance heating vapor deposition. Examples of the protective layer include metal thin films such as Al and Ag, organic films such as phthalocyanine, and inorganic films such as SiON, SiO, and SiN. Examples of the formation method include EB vapor deposition, sputtering, ion plating, and resistance heating vapor deposition.
　続いて、有機ＥＬ素子１５を少なくとも１つ用意する。具体的には、帯状の有機ＥＬ素子１５を分断し、有機ＥＬ素子１５を１個ずつに分ける。分断した有機ＥＬ素子１５の導電層６上に外部基板８を配置する。外部基板８には、配線７ａ，７ｂが形成されている。外部基板８を導電層６上に配置する際には、導電層６と該配線７ａ，７ｂとを位置合わせして配置する。このとき、配線７ａの一端が導電層６に接続される。この構成によれば、陰極５は、導電層６を介して配線７ａと電気的に接続されることになる。また、配線７ａは、下記外部基板１および外部基板８によって封止される領域の外部に伸びており、配線７ａの他端には、配線７ａよりも仕事関数の小さい外部導電層９が形成されている。当該外部導電層９には、引出配線１１ｂが接続されている。この際、外部導電層９は、絶縁されたヒートシンク、または放熱フィンと接続しており、放熱構造を有している（図示せず）。当該放熱構造によって、配線７ａが吸熱した熱を放熱することができる。なお、引出配線１１ｂとして、配線７ａの仕事関数よりも小さい材料を用いる場合は、ヒートシンク、または放熱フィンを配線７ａの他端に直接接続し、当該配線７ａに引出配線１１ｂをさらに接続した構造にしても良い。この場合は、配線７ａが吸熱した熱を引出配線１１ｂが有する放熱構造によって放熱することができるため、外部導電層９は設けなくても良い。 Subsequently, at least one organic EL element 15 is prepared. Specifically, the strip-shaped organic EL element 15 is divided, and the organic EL elements 15 are divided into one by one. An external substrate 8 is disposed on the conductive layer 6 of the divided organic EL element 15. Wirings 7 a and 7 b are formed on the external substrate 8. When the external substrate 8 is disposed on the conductive layer 6, the conductive layer 6 and the wirings 7a and 7b are aligned and disposed. At this time, one end of the wiring 7 a is connected to the conductive layer 6. According to this configuration, the cathode 5 is electrically connected to the wiring 7 a through the conductive layer 6. In addition, the wiring 7a extends outside the region sealed by the external substrate 1 and the external substrate 8 described below, and an external conductive layer 9 having a work function smaller than that of the wiring 7a is formed at the other end of the wiring 7a. ing. A lead wiring 11 b is connected to the external conductive layer 9. At this time, the external conductive layer 9 is connected to an insulated heat sink or heat radiating fin, and has a heat radiating structure (not shown). With the heat dissipation structure, the heat absorbed by the wiring 7a can be dissipated. When a material smaller than the work function of the wiring 7a is used as the lead wiring 11b, a heat sink or a heat radiating fin is directly connected to the other end of the wiring 7a, and the lead wiring 11b is further connected to the wiring 7a. May be. In this case, since the heat absorbed by the wiring 7a can be radiated by the heat dissipation structure of the lead wiring 11b, the external conductive layer 9 may not be provided.
　有機ＥＬ素子１５の陽極３は、導電部１０を介して配線７ｂと接続される。具体的には、導電部１０としてフィルム状の導電性樹脂材料を用い、同樹脂材料を介して陽極３と配線７ｂとを熱圧着することによって陽極３と配線７ｂとが接続される。なお、配線７ｂには、引出配線１１ａが接続されている。最後に、有機ＥＬ素子１５を有する外部基板８上、具体的には基板２の上面に外部基板１を当接させて固定する。このとき、ＵＶ硬化樹脂等によって、外部基板１と外部基板８との間を封止する。 The anode 3 of the organic EL element 15 is connected to the wiring 7b through the conductive portion 10. Specifically, a film-like conductive resin material is used as the conductive portion 10, and the anode 3 and the wiring 7b are connected by thermocompression bonding of the anode 3 and the wiring 7b through the resin material. The lead wiring 11a is connected to the wiring 7b. Finally, the external substrate 1 is brought into contact with and fixed to the external substrate 8 having the organic EL element 15, specifically, the upper surface of the substrate 2. At this time, the space between the external substrate 1 and the external substrate 8 is sealed with a UV curable resin or the like.
　以上のようにして、ボトムエミッション型の発光装置２０が製造される。ロールツウロール法を用いると、基板２上に有機ＥＬ素子１５を連続的に作製できるので、大型の蒸着装置の必要がなく初期投資費を抑えることができる。さらには、本製造方法では、材料利用効率が高く、パターニングのマスクも必要ないため、低コストで製造することができる。 As described above, the bottom emission type light-emitting device 20 is manufactured. When the roll-to-roll method is used, since the organic EL element 15 can be continuously produced on the substrate 2, a large vapor deposition apparatus is not necessary, and the initial investment cost can be suppressed. Furthermore, in this manufacturing method, material utilization efficiency is high and a patterning mask is not required, so that it can be manufactured at low cost.
　上記した製造方法によって得られる発光装置２０はボトムエミッション型であるが、図４に示すようなトップエミッション型の発光装置２０を製造することも可能である。図４は、トップエミッション型の発光装置２０の断面を示す図である。その製造方法について、以下に説明する。 Although the light emitting device 20 obtained by the manufacturing method described above is a bottom emission type, it is also possible to manufacture a top emission type light emitting device 20 as shown in FIG. FIG. 4 is a cross-sectional view of the top emission type light emitting device 20. The manufacturing method will be described below.
　まず、発光装置２０に搭載する有機ＥＬ素子１５を形成する。前述したように、本実施形態に係る有機ＥＬ素子１５は、ロールツーロール法によって形成されることが好ましい。その手順としては、まず基板２をロールツーロール蒸着装置にセットする。その後、セットした基板２を一定の速度で搬送する。搬送されてきた基板２上に、陰極５よりも大きい仕事関数を有する導電層６を形成する。そして、導電層６上に陰極５を形成し、各有機層４および陽極３を順番に形成していき、帯状の有機ＥＬ素子１５を形成する。得られた帯状の有機ＥＬ素子１５を再びロール状に巻き取る。このようにして、導電層６を有する帯状の有機ＥＬ素子１５ができ上がる。 First, the organic EL element 15 to be mounted on the light emitting device 20 is formed. As described above, the organic EL element 15 according to this embodiment is preferably formed by a roll-to-roll method. As the procedure, first, the substrate 2 is set in a roll-to-roll vapor deposition apparatus. Thereafter, the set substrate 2 is transported at a constant speed. A conductive layer 6 having a work function larger than that of the cathode 5 is formed on the substrate 2 that has been transported. Then, the cathode 5 is formed on the conductive layer 6, the organic layers 4 and the anode 3 are sequentially formed, and the band-shaped organic EL element 15 is formed. The obtained strip-shaped organic EL element 15 is again wound into a roll. In this way, a strip-shaped organic EL element 15 having the conductive layer 6 is completed.
　続いて、有機ＥＬ素子１５を少なくとも１つ用意する。具体的には、帯状の有機ＥＬ素子１５を分断し、有機ＥＬ素子１５を１個ずつに分ける。分断した有機ＥＬ素子１５の基板２の下に外部基板８を配置する。外部基板８には、配線７ａ，７ｂが形成されている。このとき、配線７ｂの一端が導電部１０ａを介して導電層６に接続される。具体的には、例えば、銀微粒子およびバインダ樹脂からなる銀ペースト配線部材を用いて、スクリーン印刷によって厚さ２００μｍ程度の導電部１０ａを形成する。当該導電部１０ａを導電層６と配線７ｂとの間に熱圧着することによって、導電層６と配線７ｂとは接続される。この構成によれば、陰極５は、導電層６を介して配線７ｂと電気的に接続されることになる。 Subsequently, at least one organic EL element 15 is prepared. Specifically, the strip-shaped organic EL element 15 is divided, and the organic EL elements 15 are divided into one by one. An external substrate 8 is arranged under the substrate 2 of the divided organic EL element 15. Wirings 7 a and 7 b are formed on the external substrate 8. At this time, one end of the wiring 7b is connected to the conductive layer 6 through the conductive portion 10a. Specifically, for example, the conductive portion 10a having a thickness of about 200 μm is formed by screen printing using a silver paste wiring member made of silver fine particles and a binder resin. The conductive layer 6 and the wiring 7b are connected by thermocompression bonding the conductive portion 10a between the conductive layer 6 and the wiring 7b. According to this configuration, the cathode 5 is electrically connected to the wiring 7 b through the conductive layer 6.
　配線７ｂは、外部基板１および外部基板８によって封止される領域の外部に伸びており、当該配線７ｂの他端には配線７ｂよりも仕事関数が小さい外部導電層９が形成されている。当該外部導電層９には、引出配線１１ａが接続されている。この際、外部導電層９は、絶縁されたヒートシンク、または放熱フィンと接続しており、放熱構造を有している（図示せず）。当該放熱構造によって、配線７ｂが吸熱した熱を放熱することができる。なお、引出配線１１ａとして、配線７ｂの仕事関数よりも小さい材料を用いる場合は、ヒートシンク、または放熱フィンを配線７ｂの他端に直接接続し、当該配線７ｂに引出配線１１ａをさらに接続した構造にしても良い。この場合は、引出配線１１ｂが有する放熱構造によって配線７ｂが吸熱した熱を放熱することができるため、外部導電層９は設けなくても良い。 The wiring 7b extends outside a region sealed by the external substrate 1 and the external substrate 8, and an external conductive layer 9 having a work function smaller than that of the wiring 7b is formed at the other end of the wiring 7b. A lead wiring 11 a is connected to the external conductive layer 9. At this time, the external conductive layer 9 is connected to an insulated heat sink or heat radiating fin, and has a heat radiating structure (not shown). With the heat dissipation structure, the heat absorbed by the wiring 7b can be dissipated. When a material smaller than the work function of the wiring 7b is used as the extraction wiring 11a, a heat sink or a heat radiation fin is directly connected to the other end of the wiring 7b, and the extraction wiring 11a is further connected to the wiring 7b. May be. In this case, since the heat absorbed by the wiring 7b can be radiated by the heat dissipation structure of the lead wiring 11b, the external conductive layer 9 may not be provided.
　有機ＥＬ素子１５の陽極３は、導電部１０ｂを介して配線７ａと接続される。具体的には、導電部１０ａと同様にして導電部１０ｂを形成することによって、陽極３と配線７ａとは接続される。なお、配線７ａは、下記外部基板１および外部基板８によって封止される領域の外部に伸びており、当該配線７ａの他端には、引出配線１１ｂが接続されている。最後に、有機ＥＬ素子１５を有する外部基板８上、具体的には陽極３の上面に外部基板１を当接させて固定する。このとき、ＵＶ硬化樹脂等によって、外部基板１と外部基板８との間を封止する。 The anode 3 of the organic EL element 15 is connected to the wiring 7a through the conductive portion 10b. Specifically, the anode 3 and the wiring 7a are connected by forming the conductive portion 10b in the same manner as the conductive portion 10a. Note that the wiring 7a extends to the outside of the region sealed by the external substrate 1 and the external substrate 8 described below, and a lead-out wiring 11b is connected to the other end of the wiring 7a. Finally, the external substrate 1 is abutted and fixed on the external substrate 8 having the organic EL element 15, specifically, the upper surface of the anode 3. At this time, the space between the external substrate 1 and the external substrate 8 is sealed with a UV curable resin or the like.
　以上のようにして、トップエミッション型の発光装置２０が製造される。
なお、本実施形態に係る発光装置２０には、２個以上の有機ＥＬ素子１５を搭載することが可能である。この際、補色となる有機ＥＬ素子１５同士を組み合わせて基板２上に配置しても良い。また、赤色に発光する有機ＥＬ素子１５、緑色に発光する有機ＥＬ素子１５、および青色に発光する有機ＥＬ素子１５の３個の有機ＥＬ素子１５を組み合わせて基板２上に配置しても良い。これによって、発光装置２０が発光する光の色を任意に調整することが可能となり、演色性を高めることができる。 As described above, the top emission type light emitting device 20 is manufactured.
Note that two or more organic EL elements 15 can be mounted on the light emitting device 20 according to the present embodiment. At this time, organic EL elements 15 that are complementary colors may be combined and disposed on the substrate 2. Alternatively, the three organic EL elements 15, that is, the organic EL element 15 that emits red light, the organic EL element 15 that emits green light, and the organic EL element 15 that emits blue light may be combined and disposed on the substrate 2. As a result, the color of light emitted from the light emitting device 20 can be arbitrarily adjusted, and color rendering can be improved.
　有機ＥＬ素子１５には、長辺方向に沿って局所または全体に補助電極を設けることが好ましい。これによって、電極の抵抗による電圧の低下を低減し、有機ＥＬ素子１５の発光のむらをなくすことができる。補助電極としては、導電性に優れたＡｌ、Ａｕ、Ａｇ、またはＣｕ等の金属を用いることができる。 The organic EL element 15 is preferably provided with an auxiliary electrode locally or entirely along the long side direction. As a result, the voltage drop due to the resistance of the electrode can be reduced, and unevenness in the light emission of the organic EL element 15 can be eliminated. As the auxiliary electrode, a metal such as Al, Au, Ag, or Cu having excellent conductivity can be used.
　また、発光素子２０を備えた有機エレクトロルミネッセンス表示装置を実現することも可能である。 It is also possible to realize an organic electroluminescence display device including the light emitting element 20.
　本発明は上述した実施形態に限定されるものではなく、請求項に示した範囲で種々の変更が可能である。すなわち、請求項に示した範囲で適宜変更した技術的手段を組み合わせて得られる実施形態についても本発明の技術的範囲に含まれる。 The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope indicated in the claims. That is, embodiments obtained by combining technical means appropriately changed within the scope of the claims are also included in the technical scope of the present invention.
　〔実施形態の総括〕
　以上のように、本発明に係る発光装置においては、前記導電層は、前記第二電極上に形成されており、前記第一電極側から前記光を取り出すことが好ましい。 [Summary of Embodiment]
As described above, in the light emitting device according to the present invention, it is preferable that the conductive layer is formed on the second electrode, and the light is extracted from the first electrode side.
　上記の構成によれば、本発明に係る発光装置を、ボトムエミッション型発光装置として実現することができる。 According to the above configuration, the light emitting device according to the present invention can be realized as a bottom emission type light emitting device.
　また、本発明に係る発光装置においては、前記導電層は、前記基板と前記第一電極との間に形成されており、前記第二電極側から前記光を取り出すことが好ましい。 In the light emitting device according to the present invention, it is preferable that the conductive layer is formed between the substrate and the first electrode, and the light is extracted from the second electrode side.
　上記の構成によれば、本発明に係る発光装置を、トップエミッション型発光装置として実現することができる。 According to the above configuration, the light emitting device according to the present invention can be realized as a top emission type light emitting device.
　また、本発明に係る発光装置においては、前記基板上配線は、前記導電層の仕事関数よりも大きい仕事関数を有することが好ましい。 In the light emitting device according to the present invention, it is preferable that the wiring on the substrate has a work function larger than a work function of the conductive layer.
　上記の構成によれば、ペルチェ効果がより一層誘起されるので、導電層が吸熱した熱を第一配線がより効率良く吸熱する。したがって、有機ＥＬ素子が発した熱をより効率的に取り除くことができる。 According to the above configuration, since the Peltier effect is further induced, the first wiring absorbs the heat absorbed by the conductive layer more efficiently. Therefore, the heat generated by the organic EL element can be removed more efficiently.
　また、本発明に係る発光装置においては、前記放熱構造は、放熱フィンおよびヒートシンクのいずれかであることを特徴としている。 Further, in the light emitting device according to the present invention, the heat dissipation structure is any one of a heat dissipation fin and a heat sink.
　上記の構成によれば、外部導電層が効率良く放熱をすることができ、誘起ＥＬ素子の発熱を効率的に取り除くことができる。 According to the above configuration, the external conductive layer can dissipate heat efficiently, and the heat generation of the induced EL element can be efficiently removed.
　さらに、本発明に係る発光装置の製造方法では、前記有機エレクトロルミネッセンス素子を、ロールツーロール法によって形成することが好ましい。 Furthermore, in the method for manufacturing a light emitting device according to the present invention, the organic electroluminescence element is preferably formed by a roll-to-roll method.
　上記の構成によれば、本発明に係る有機ＥＬ素子を連続的に量産することができるので、製造コストを抑えることができる。 According to the above configuration, since the organic EL element according to the present invention can be continuously mass-produced, the manufacturing cost can be suppressed.
　発明の詳細な説明の項においてなされた具体的な実施形態または実施例は、あくまでも、本発明の技術内容を明らかにするものであって、そのような具体例にのみ限定して狭義に解釈されるべきものではなく、本発明の精神と次に記載する請求の範囲内で、いろいろと変更して実施することができるものである。 The specific embodiments or examples made in the detailed description section of the invention are merely to clarify the technical contents of the present invention, and are limited to such specific examples and are interpreted in a narrow sense. It should be understood that various modifications may be made within the spirit of the invention and the scope of the following claims.
　以下、実施例および比較例を挙げて本発明をさらに詳しく説明するが、本発明はその要旨を超えない限り、これら実施例に限定されるものではない。 Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples. However, the present invention is not limited to these examples unless it exceeds the gist.
　（実施例１）
　１０ｍ×２０ｍｍのＰＥＴフィルムの表面にＩＴＯから成る下電極（陽極）を有する基板を用意した。当該フィルム基板を、アセトンおよびＩＰＡ（イソピルアルコール）を用いて、超音波洗浄を１０分間行った。その後、ＵＶオゾン洗浄を３０分間行った。洗浄したフィルム基板を、ロールツーロール蒸着装置にセットし、当該フィルム基板を１ｍ／ｓｅｃの定速で搬送した。 Example 1
A substrate having a lower electrode (anode) made of ITO on the surface of a 10 m × 20 mm PET film was prepared. The film substrate was subjected to ultrasonic cleaning for 10 minutes using acetone and IPA (isopropyl alcohol). Thereafter, UV ozone cleaning was performed for 30 minutes. The cleaned film substrate was set in a roll-to-roll vapor deposition apparatus, and the film substrate was conveyed at a constant speed of 1 m / sec.
　搬送されてきたフィルム基板上の陽極の表面に、ＣｕＰｃ（銅フタロシアニン）を用いて厚さ３０ｎｍ程度の正孔注入層を真空蒸着法によって形成した。 A hole injection layer having a thickness of about 30 nm was formed on the surface of the anode on the conveyed film substrate using CuPc (copper phthalocyanine) by vacuum deposition.
Figure JPOXMLDOC01-appb-C000001
Figure JPOXMLDOC01-appb-C000001
　次いで、正孔注入層の上には、α－ＮＰＤ（４’－ビス［Ｎ－（１－ナフチル）－Ｎ－フェニル－アミノ］ビフェニル））を用いて厚さ２０ｎｍ程度の正孔輸送層を真空蒸着法によって形成した。 Next, a hole transport layer having a thickness of about 20 nm is formed on the hole injection layer using α-NPD (4′-bis [N- (1-naphthyl) -N-phenyl-amino] biphenyl)). It formed by the vacuum evaporation method.
Figure JPOXMLDOC01-appb-C000002
Figure JPOXMLDOC01-appb-C000002
　正孔輸送層の上には、ＨＭＴＰＤ（４，４’－ビス－［Ｎ，Ｎ’－（３－トリル）アミノ－３，３’－ジメチルビフェニル］を用いて厚さ３０ｎｍ程度の電子ブロッキング層を真空蒸着法によって形成した。 An electron blocking layer having a thickness of about 30 nm is formed on the hole transport layer using HMTPD (4,4′-bis- [N, N ′-(3-tolyl) amino-3,3′-dimethylbiphenyl]. Was formed by vacuum evaporation.
Figure JPOXMLDOC01-appb-C000003
Figure JPOXMLDOC01-appb-C000003
　電子ブロッキング層の上には、厚さ２０ｎｍ程度の両電荷輸送性赤色発光層を真空蒸着法によって形成した。当該両電荷輸送性赤色発光層は、α－ＮＰＤ（正孔輸送材料）とＴＡＺ（３－フェニル－４（１’－ナフチル）－５－フェニル－１，２，４－トリアゾール）（電子輸送材料）とｂｔｐ２Ｉｒ（ａｃａｃ）（ビス（２－（２’－ベンゾ［４，５－α］チエニル）ピリジナト－Ｎ、Ｃ３’）イリジウム（アセチルアセトネ－ト））（赤色発光ド－パント）とをそれぞれの蒸着速度の比率が０．６：１．４：０．１５になるように制御し、共蒸着させて形成した。 On the electron blocking layer, a dual charge transporting red light emitting layer having a thickness of about 20 nm was formed by vacuum deposition. The charge transporting red light emitting layer includes α-NPD (hole transport material) and TAZ (3-phenyl-4 (1′-naphthyl) -5-phenyl-1,2,4-triazole) (electron transport material). ) And btp 2 Ir (acac) (bis (2- (2′-benzo [4,5-α] thienyl) pyridinato-N, C3 ′) iridium (acetylacetonate)) (red emitting dopant) Were formed by co-deposition by controlling the ratio of the respective deposition rates to be 0.6: 1.4: 0.15.
Figure JPOXMLDOC01-appb-C000004
Figure JPOXMLDOC01-appb-C000004
Figure JPOXMLDOC01-appb-C000005
Figure JPOXMLDOC01-appb-C000005
　次いで、両電荷輸送性赤色発光層の上には、厚さ２０ｎｍ程度の両電荷輸送性緑色発光層を真空蒸着法によって形成した。当該両電荷輸送性緑色発光層は、α－ＮＰＤ（正孔輸送材料）とＴＡＺ（電子輸送材料）とＩｒ（ｐｐｙ）３（トリ（２－フェニルピリジン）イリジウム）（緑色発光ド－パント）とをそれぞれの蒸着速度の比率が１．０：１．０：０．１になるように制御し、共蒸着させて形成した。 Next, on the both charge transporting red light emitting layer, a both charge transporting green light emitting layer having a thickness of about 20 nm was formed by vacuum deposition. The charge transporting green light emitting layer includes α-NPD (hole transport material), TAZ (electron transport material), Ir (ppy) 3 (tri (2-phenylpyridine) iridium) (green light emitting dopant), and Were formed by co-deposition by controlling the ratio of the respective deposition rates to be 1.0: 1.0: 0.1.
Figure JPOXMLDOC01-appb-C000006
Figure JPOXMLDOC01-appb-C000006
　さらに、両電荷輸送性緑色発光層の上には、厚さ１０ｎｍ程度の両電荷輸送性青色発光層を真空蒸着法によって形成した。当該両電荷輸送性青色発光は、α－ＮＰＤ（正孔輸送材料）とＴＡＺ（電子輸送材料）とｔ－ＢｕＰＢＤ（２－（４’－ｔ－ブチルフェニル）－５－（４”－ビフェニルイル）－１，３，４－オキサジアゾ－ル）（青色発光ド－パント）とをそれぞれの蒸着速度の比率が１．５：０．５：０．２となるように制御し、共蒸着させて形成した。これにより、白色の発光層が得られた。 Furthermore, on the both charge transporting green light emitting layer, a both charge transporting blue light emitting layer having a thickness of about 10 nm was formed by vacuum deposition. The dual charge transporting blue light emission includes α-NPD (hole transport material), TAZ (electron transport material) and t-BuPBD (2- (4′-t-butylphenyl) -5- (4 ″ -biphenylyl). ) -1,3,4-oxadiazol) (blue light emitting dopant), and the ratio of the respective vapor deposition rates is controlled to be 1.5: 0.5: 0.2 and co-deposited. This formed a white light-emitting layer.
Figure JPOXMLDOC01-appb-C000007
Figure JPOXMLDOC01-appb-C000007
　次に、発光層の上には、ＢＣＰ（２，９－ジメチル－４，７－ジフェニル－１，１０－フェナントロリン）を用いて厚さ１０ｎｍ程度の正孔ブロッキング層を真空蒸着法によって形成した。 Next, a hole blocking layer having a thickness of about 10 nm was formed on the light emitting layer by vacuum deposition using BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline).
Figure JPOXMLDOC01-appb-C000008
Figure JPOXMLDOC01-appb-C000008
　次いで、正孔ブロッキング層の上には、Ａｌｑ３（トリス（８－ヒドロキシキノリン）アルミニウム）を用いて厚さ３０ｎｍ程度の電子輸送層を形成した。 Next, an electron transport layer having a thickness of about 30 nm was formed on the hole blocking layer by using Alq 3 (tris (8-hydroxyquinoline) aluminum).
　そして、電子輸送層の上には、ＬｉＦを用いて厚さ１ｎｍ程度の電子注入層を真空蒸着法によって形成した。 Then, on the electron transport layer, an electron injection layer having a thickness of about 1 nm was formed by vacuum deposition using LiF.
　さらに、電子注入層の表面には、真空蒸着法によってアルミニウムを堆積した。これにより、厚さ３００ｎｍ程度の上電極（陰極）が形成され、帯状の有機ＥＬ素子が形成された。 Furthermore, aluminum was deposited on the surface of the electron injection layer by vacuum evaporation. As a result, an upper electrode (cathode) having a thickness of about 300 nm was formed, and a band-shaped organic EL element was formed.
　形成した帯状の有機ＥＬ素子の陰極上にアルミニウムよりも大きい仕事関数を持つ白金－パラジウムを厚さ２０００Å以下に堆積した。これによって、帯状の有機ＥＬ素子の陰極上に、導電層が形成された。 Platinum-palladium having a work function larger than that of aluminum was deposited on the cathode of the formed strip-shaped organic EL element to a thickness of 2000 mm or less. As a result, a conductive layer was formed on the cathode of the strip-shaped organic EL element.
　導電層を有する帯状の有機ＥＬ素子を、１５ｃｍの長さに分断し、６本の有機ＥＬ素子を得た。得られた有機ＥＬ素子を５ｍｍ間隔でガラス基板上に固定した。この際、陰極側をガラス基板に当接させた。ガラス基板上には、予め白金－パラジウムの配線が形成されており、当該配線は各有機ＥＬ素子の陽極および陰極部に並列に電気的に接続している。陰極に接続している配線の端部には外部電極層として白金－パラジウム上にアルミニウム層を形成した。 A strip-shaped organic EL element having a conductive layer was divided into 15 cm lengths to obtain six organic EL elements. The obtained organic EL element was fixed on the glass substrate at intervals of 5 mm. At this time, the cathode side was brought into contact with the glass substrate. On the glass substrate, platinum-palladium wiring is formed in advance, and the wiring is electrically connected in parallel to the anode and cathode of each organic EL element. An aluminum layer was formed on platinum-palladium as an external electrode layer at the end of the wiring connected to the cathode.
　最後に、有機ＥＬ素子を有するガラス基板上に、ＵＶ硬化樹脂を用いて封止用のガラス基板を固定し、外部電極層には放熱用のフィンを接続した。この際、水分等による劣化を防止するために、当該作業はドライエア－ブ－ス中で行った。 Finally, a glass substrate for sealing was fixed using a UV curable resin on a glass substrate having an organic EL element, and fins for heat dissipation were connected to the external electrode layer. At this time, in order to prevent deterioration due to moisture or the like, the operation was performed in a dry air boot.
　以上のようにして作製した有機ＥＬ素子を６本搭載した発光装置に、１０Ｖの電圧を印加すると、６０００ｃｄ／ｍ２の白色発光が得られた。発光装置を６０００ｃｄ／ｍ２で１０分間発光させ、有機ＥＬ素子の温度を測定したところ、３０度であった。 When a voltage of 10 V was applied to the light emitting device on which six organic EL elements produced as described above were mounted, white light emission of 6000 cd / m 2 was obtained. The light emitting device emitted light at 6000 cd / m 2 for 10 minutes, and the temperature of the organic EL element was measured and found to be 30 degrees.
　（比較例１）
　実施例１と同様にして帯状の有機ＥＬ素子を形成した後、陰極上には白金－パラジウムを堆積せずに、帯状の有機ＥＬ素子を１５ｃｍの長さに分断し、６本の有機ＥＬ素子を得た。各有機ＥＬ素子を実施例１と同様にしてガラス基板上に固定した。この際、ガラス基板上には、予めアルミニウムの配線を形成した。そして、実施例１と同様にして有機ＥＬ素子を有するガラス基板上に封止用のガラス基板を固定し、外部電極層には放熱用のフィンを接続した。 (Comparative Example 1)
After forming a strip-shaped organic EL device in the same manner as in Example 1, the strip-shaped organic EL device was divided into 15 cm lengths without depositing platinum-palladium on the cathode, and six organic EL devices were obtained. Got. Each organic EL element was fixed on a glass substrate in the same manner as in Example 1. At this time, aluminum wiring was previously formed on the glass substrate. And the glass substrate for sealing was fixed on the glass substrate which has an organic EL element like Example 1, and the fin for thermal radiation was connected to the external electrode layer.
　実施例１と同様にして作製した発光装置に、１０Ｖの電圧を印加すると、６０００ｃｄ／ｍ２の白色発光が得られた。発光装置を６０００ｃｄ／ｍ２で１０分間発光させ、有機ＥＬ素子の温度を測定したところ、４３度であった。 When a voltage of 10 V was applied to the light emitting device manufactured in the same manner as in Example 1, white light emission of 6000 cd / m 2 was obtained. The light emitting device emitted light at 6000 cd / m 2 for 10 minutes, and the temperature of the organic EL element was measured and found to be 43 degrees.
　比較例１の発光装置は、導電層を有していないため、アルミニウム電極（陰極）の上には、アルミニウムの配線が接続されている。さらに、アルミニウムの配線の端部には、外部電極層としてアルミニウム層が形成されている。したがって、陰極と配線と外部電極層とはすべてアルミニウムからできており、仕事関数に差がない。一方、実施例１の発光装置は、陰極よりも大きい仕事関数を持つ導電層を、陰極上に有しており、なおかつ配線の端部には、外部電極層としてアルミニウム層が形成されている。したがって、導電層の仕事関数は陰極の仕事関数よりも大きく、外部電極層の仕事関数は配線よりも小さい構成になっている。この構成によれば、有機ＥＬ素子で生じた熱は陰極に伝熱するが、陰極よりも導電層の方が大きい仕事関数を有しているため、陰極の熱は導電層に吸熱される。さらに、導電層が吸熱した熱は配線に伝熱するが、配線よりも外部導電層の方が小さい仕事関数を有しているため、配線の熱はすぐに外部導電層に伝熱される。そして、外部電極層が有する放熱用のフィンによって、外部電極層の熱が放熱される。そのため、実施例１の発光装置を１０分間駆動した場合の有機ＥＬ素子の温度は３０度と低温であったのに対し、比較例１の発光装置を１０分間駆動した場合の有機ＥＬ素子の温度は、４３度と高温であった。 Since the light emitting device of Comparative Example 1 does not have a conductive layer, aluminum wiring is connected on the aluminum electrode (cathode). Further, an aluminum layer is formed as an external electrode layer at the end of the aluminum wiring. Therefore, the cathode, the wiring, and the external electrode layer are all made of aluminum, and there is no difference in work function. On the other hand, the light emitting device of Example 1 has a conductive layer having a work function larger than that of the cathode on the cathode, and an aluminum layer is formed as an external electrode layer at the end of the wiring. Therefore, the work function of the conductive layer is larger than that of the cathode, and the work function of the external electrode layer is smaller than that of the wiring. According to this configuration, the heat generated in the organic EL element is transferred to the cathode. However, since the conductive layer has a larger work function than the cathode, the heat of the cathode is absorbed by the conductive layer. Furthermore, although the heat absorbed by the conductive layer is transferred to the wiring, the heat of the wiring is immediately transferred to the external conductive layer because the external conductive layer has a smaller work function than the wiring. Then, the heat of the external electrode layer is radiated by the heat dissipation fin of the external electrode layer. Therefore, the temperature of the organic EL element when the light emitting device of Example 1 is driven for 10 minutes is as low as 30 degrees, whereas the temperature of the organic EL element when the light emitting device of Comparative Example 1 is driven for 10 minutes. Was as high as 43 degrees.
　本発明に係る発光装置は、例えば有機エレクトロルミネッセンス素子を利用する表示装置等に用いることができる。 The light emitting device according to the present invention can be used, for example, for a display device using an organic electroluminescence element.
１　外部基板
２　基板
３　陽極
４　有機層
４ａ　正孔注入層
４ｂ　正孔輸送層
４ｃ　発光層
４ｄ　電子ブロッキング層
４ｅ　電子輸送層
５　陰極
６　導電層
７ａ，７ｂ　配線（基板上配線）
８　外部基板
９　外部導電層
１０，１０ａ，１０ｂ　導電部
１１ａ，１１ｂ　引出配線
１５　有機ＥＬ素子
２０　発光装置 DESCRIPTION OF SYMBOLS 1 External substrate 2 Substrate 3 Anode 4 Organic layer 4a Hole injection layer 4b Hole transport layer 4c Light emitting layer 4d Electron blocking layer 4e Electron transport layer 5 Cathode 6 Conductive layers 7a and 7b Wiring (on-substrate wiring)
8 External substrate 9 External conductive layers 10, 10a, 10b Conductive portions 11a, 11b Lead wiring 15 Organic EL element 20 Light emitting device

Claims (9)

  1. 　少なくとも第一電極、発光層および第二電極を順次積層して成る有機エレクトロルミネッセンス素子を、少なくとも１つ搭載した発光装置であって、
    　前記発光層からの光を取り出す光取り出し側に形成された第一外部基板と、
    　前記第一電極および第二電極のうち前記光取り出し側の反対側に形成されている電極に接し、かつ当該電極の仕事関数よりも大きい仕事関数を有する導電層と、
    　前記第一外部基板に対向して配置され、かつ前記第一外部基板と共に前記有機エレクトロルミネッセンス素子を封止する第二外部基板と、
    　前記第二外部基板に形成され、一端が前記導電層に接続されるとともに、他端が前記第一外部基板および前記第二外部基板によって封止された領域の外部に伸び、かつ前記導電層の仕事関数以上の仕事関数を有する基板上配線と、
    　前記基板上配線の他端に形成され、当該基板上配線の仕事関数よりも小さい仕事関数を有し、かつ放熱構造を有する外部導電層とを備えていることを特徴とする発光装置。     A light-emitting device having at least one organic electroluminescence element formed by sequentially laminating at least a first electrode, a light-emitting layer, and a second electrode,
    A first external substrate formed on the light extraction side for extracting light from the light emitting layer;
    A conductive layer in contact with an electrode formed on the opposite side of the light extraction side of the first electrode and the second electrode, and having a work function larger than the work function of the electrode;
    A second external substrate disposed opposite the first external substrate and encapsulating the organic electroluminescence element together with the first external substrate;
    Formed on the second external substrate, having one end connected to the conductive layer, the other end extending outside the region sealed by the first external substrate and the second external substrate, and the conductive layer Wiring on the substrate having a work function equal to or higher than the work function;
    A light emitting device comprising: an external conductive layer formed on the other end of the wiring on the substrate, having a work function smaller than that of the wiring on the substrate, and having a heat dissipation structure.
  2. 　前記導電層は、前記第二電極上に形成されており、
    　前記第一電極側から前記光を取り出すことを特徴とする請求項１に記載の発光装置。     The conductive layer is formed on the second electrode;
    The light emitting device according to claim 1, wherein the light is extracted from the first electrode side.
  3. 　前記導電層は、前記基板と前記第一電極との間に形成されており、
    　前記第二電極側から前記光を取り出すことを特徴とする請求項１に記載の発光装置。     The conductive layer is formed between the substrate and the first electrode,
    The light emitting device according to claim 1, wherein the light is extracted from the second electrode side.
  4. 　前記基板上配線は、前記導電層の仕事関数よりも大きい仕事関数を有することを特徴とする請求項１～３のいずれか１項に記載の発光装置。 The light emitting device according to any one of claims 1 to 3, wherein the wiring on the substrate has a work function larger than a work function of the conductive layer.
  5. 　前記放熱構造は、放熱フィンまたはヒートシンクのいずれかであることを特徴とする請求項１～４のいずれか１項に記載の発光装置。 The light emitting device according to any one of claims 1 to 4, wherein the heat dissipation structure is either a heat dissipation fin or a heatsink.
  6. 　基板上に少なくとも第一電極、発光層および第二電極を、前記第一電極、前記発光層、および前記第二電極の順に形成することによって、有機エレクトロルミネッセンス素子を形成する工程と、
    　前記有機エレクトロルミネッセンス素子を少なくとも１つ用意する工程と、
    　前記第二電極上に、当該第二電極の仕事関数よりも大きい仕事関数を有する導電層を形成する工程と、
    　前記基板の下面に第一外部基板を当接する工程と、
    　前記導電層の仕事関数以上の仕事関数を有する基板上配線が形成された第二外部基板を、当該基板上配線の一端を前記導電層に接続させるように前記第一外部基板に対向して配置することによって、前記有機エレクトロルミネッセンス素子を封止する工程と、
    　前記基板上配線の仕事関数よりも小さい仕事関数を有し、かつ放熱構造を有する外部導電層を、前記第一外部基板および前記第二外部基板によって封止された領域の外部に伸びた前記基板上配線の他端に設ける工程とを含むことを特徴とする発光装置の製造方法。     Forming an organic electroluminescent element by forming at least a first electrode, a light emitting layer, and a second electrode on the substrate in the order of the first electrode, the light emitting layer, and the second electrode;
    Preparing at least one organic electroluminescence element;
    Forming a conductive layer having a work function larger than the work function of the second electrode on the second electrode;
    Contacting the first external substrate to the lower surface of the substrate;
    A second external substrate on which a wiring on the substrate having a work function equal to or higher than the work function of the conductive layer is formed so as to face the first external substrate so that one end of the wiring on the substrate is connected to the conductive layer. A step of sealing the organic electroluminescence element,
    The substrate having an external conductive layer having a work function smaller than a work function of the wiring on the substrate and having a heat dissipation structure extended outside a region sealed by the first external substrate and the second external substrate And a step of providing at the other end of the upper wiring.
  7. 　基板上に少なくとも第一電極、発光層、第二電極および前記第一電極の仕事関数よりも大きい仕事関数を有する導電層を、前記導電層、前記第一電極、前記発光層、および前記第二電極の順に形成することによって、前記導電層を備えた有機エレクトロルミネッセンス素子を形成する工程と、
    　前記有機エレクトロルミネッセンス素子を少なくとも１つ用意する工程と、
    　前記第二電極の上面に第一外部基板を当接する工程と、
    　前記導電層の仕事関数以上の仕事関数を有する基板上配線が形成された第二外部基板を、当該基板上配線の一端を前記導電層に接続させるように前記第一外部基板に対向して配置することによって、前記有機エレクトロルミネッセンス素子を封止する工程と、
    　前記基板上配線の仕事関数よりも小さい仕事関数を有し、かつ放熱構造を有する外部導電層を、前記第一外部基板および前記第二外部基板によって封止された領域の外部に伸びた前記基板上配線の端部に設ける工程とを含むことを特徴とする発光装置の製造方法。     A conductive layer having a work function larger than that of at least the first electrode, the light emitting layer, the second electrode, and the first electrode on the substrate, the conductive layer, the first electrode, the light emitting layer, and the second Forming an organic electroluminescence element including the conductive layer by forming the electrodes in order, and
    Preparing at least one organic electroluminescence element;
    Contacting the first external substrate with the upper surface of the second electrode;
    A second external substrate on which a wiring on the substrate having a work function equal to or higher than the work function of the conductive layer is formed so as to face the first external substrate so that one end of the wiring on the substrate is connected to the conductive layer. A step of sealing the organic electroluminescence element,
    The substrate having an external conductive layer having a work function smaller than a work function of the wiring on the substrate and having a heat dissipation structure extended outside a region sealed by the first external substrate and the second external substrate And a step of providing at an end portion of the upper wiring.
  8. 　前記有機エレクトロルミネッセンス素子を、ロールツーロール法によって形成することを特徴とする請求項６または７に記載の発光装置の製造方法。 The method for manufacturing a light emitting device according to claim 6 or 7, wherein the organic electroluminescence element is formed by a roll-to-roll method.
  9. 　請求項１～５のいずれか１項に記載の発光装置を備えていることを特徴としている有機エレクトロルミネッセンス表示装置。 An organic electroluminescence display device comprising the light-emitting device according to any one of claims 1 to 5.
PCT/JP2010/068519 2009-10-21 2010-10-20 Light-emitting device equipped with organic electroluminescent element, process for production of the light-emitting device, and organic electroluminescent display device equipped with the light-emitting device WO2011049141A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2009-242469 2009-10-21
JP2009242469 2009-10-21

Publications (1)

Publication Number Publication Date
WO2011049141A1 true WO2011049141A1 (en) 2011-04-28

Family

ID=43900364

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2010/068519 WO2011049141A1 (en) 2009-10-21 2010-10-20 Light-emitting device equipped with organic electroluminescent element, process for production of the light-emitting device, and organic electroluminescent display device equipped with the light-emitting device

Country Status (1)

Country Link
WO (1) WO2011049141A1 (en)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005338419A (en) * 2004-05-26 2005-12-08 Matsushita Electric Works Ltd Sealing body for surface light emitting device, and surface light emitting device
JP2007026970A (en) * 2005-07-20 2007-02-01 Hitachi Displays Ltd Organic light emitting display device
JP2007242243A (en) * 2006-03-03 2007-09-20 Seiko Epson Corp Organic semiconductor device and electronic apparatus
JP2008047298A (en) * 2006-08-10 2008-02-28 Pentax Corp Organic electroluminescent element
JP2008089633A (en) * 2006-09-29 2008-04-17 Seiko Epson Corp Electro-optical device and electronic apparatus
JP2008234841A (en) * 2007-03-16 2008-10-02 Seiko Epson Corp Light-emitting device
JP2010061074A (en) * 2008-09-08 2010-03-18 Seiko Epson Corp Electro-optical apparatus
JP2010536155A (en) * 2007-08-14 2010-11-25 フラウンホーファーゲゼルシャフト ツール フォルデルング デル アンゲヴァンテン フォルシユング エー．フアー． Organic electronic device

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2005338419A (en) * 2004-05-26 2005-12-08 Matsushita Electric Works Ltd Sealing body for surface light emitting device, and surface light emitting device
JP2007026970A (en) * 2005-07-20 2007-02-01 Hitachi Displays Ltd Organic light emitting display device
JP2007242243A (en) * 2006-03-03 2007-09-20 Seiko Epson Corp Organic semiconductor device and electronic apparatus
JP2008047298A (en) * 2006-08-10 2008-02-28 Pentax Corp Organic electroluminescent element
JP2008089633A (en) * 2006-09-29 2008-04-17 Seiko Epson Corp Electro-optical device and electronic apparatus
JP2008234841A (en) * 2007-03-16 2008-10-02 Seiko Epson Corp Light-emitting device
JP2010536155A (en) * 2007-08-14 2010-11-25 フラウンホーファーゲゼルシャフト ツール フォルデルング デル アンゲヴァンテン フォルシユング エー．フアー． Organic electronic device
JP2010061074A (en) * 2008-09-08 2010-03-18 Seiko Epson Corp Electro-optical apparatus

Similar Documents

Publication Publication Date Title
JP4736890B2 (en) Organic electroluminescence device
JP5476061B2 (en) Organic electroluminescence device and method for manufacturing the same
WO2009142030A1 (en) Organic electroluminescent device, display device and illuminating device
US8497497B2 (en) Organic electroluminescent element, method for manufacturing the organic electroluminescent element, and light emitting display device
TWI599030B (en) Organic light-emitting element
WO2011001567A1 (en) Organic el light emitter, organic el lighting device, and process for production of organic el light emitter
JP2004014172A (en) Organic electroluminescent element, and its production method and application
JP4544937B2 (en) Organic functional device, organic EL device, organic semiconductor device, organic TFT device, and manufacturing method thereof
US8901804B2 (en) Organic EL illumination device and method for manufacturing the same
US20140326976A1 (en) Organic electroluminescent element
JP2009277791A (en) Organic el element
US8525163B2 (en) Organic EL device, method for fabricating organic EL device, and organic EL illumination system
JP5672705B2 (en) Light emitting device and manufacturing method thereof
WO2010119503A1 (en) Organic electroluminescent element and manufacturing method thereof
JP2004047381A (en) Flexible organic electroluminescent element, manufacturing method of same, information display device, and lighting device
JP5277319B2 (en) Organic EL device and manufacturing method thereof
WO2011024346A1 (en) Organic electroluminescent element, organic electroluminescent display device, and organic electroluminescent illuminating device
WO2011049141A1 (en) Light-emitting device equipped with organic electroluminescent element, process for production of the light-emitting device, and organic electroluminescent display device equipped with the light-emitting device
JP2008078036A (en) Organic electroluminescent element and organic electroluminescent display
JP4315755B2 (en) Organic EL device
KR101291801B1 (en) Manufactuing Method Of Organic Light Emitting Diode Device
JP2007096270A (en) Electroluminescent element
JP2005235564A (en) Organic el device
WO2013024885A1 (en) Method for manufacturing organic electroluminescence element

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: 10824990

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 10824990

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP