JP2011065800A - Organic el device, method of manufacturing the same, and electronic equipment equipped with this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL device, and a method of manufacturing the same, with emission life and emission efficiency improved as compared with a conventional one, as well as an electronic equipment equipped with the same. <P>SOLUTION: The organic EL device 1 is provided with an element substrate 20, and an organic EL element 8 fitted on the element substrate 20 with an anode 24, an organic function layer 30 and a cathode 26 laminated in turn. The organic function layer 30 at least contains a hole transport layer 32, a red-color light-emitting layer 33, an intermediate layer 34 adjusting flow of electrons and holes, a blue-color light-emitting layer 35, a green-color light-emitting layer 36, and an electron transport layer 37 containing a diffusion layer 37b with alkali metal or alkaline earth metal diffused, arranged in turn on the anode 24, and the organic EL element 8 is put under heat treatment at a temperature higher than the lowest among glass transition temperatures of respective materials constituting the organic function layer 30. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an organic EL device, a method for manufacturing the same, and an electronic apparatus including the same.

  An organic electroluminescence element (hereinafter referred to as an organic EL element) is known as a light emitting element using a phenomenon in which light is emitted by recombination of electrons and holes. The organic EL element includes an organic functional layer including a light emitting layer between an anode that supplies holes and a cathode that supplies electrons. The organic EL element emits light by recombination of holes supplied from the anode and electrons supplied from the cathode in the organic functional layer.

  Incidentally, it is known that the organic EL element has a light emission luminance that decreases as the driving time becomes longer, and also has a light emission efficiency that decreases with respect to a current flowing through the organic functional layer. In addition, in the initial stage after the formation of the organic EL element, the light emission luminance and the light emission efficiency may be significantly reduced. If such an organic EL element is used as it is as a light emitting element after it is formed, desired characteristics cannot be obtained in a short time, and display quality may be deteriorated.

  Therefore, initial deterioration of the formed organic EL element is performed so that the change in the light emission characteristics and the change in the electrical characteristics of the organic EL element in a state where it is used as an organic electroluminescence device (hereinafter referred to as an organic EL device) is reduced. There has been proposed a method for stabilizing the light emission characteristics and electrical characteristics by (aging) (for example, Patent Document 1). In the method described in Patent Document 1, aging is performed by applying heat treatment to the organic EL element or applying an electric field.

JP 2003-264073 A

  However, depending on the temperature and the heating time during the heat treatment, there is a problem that the characteristics of the organic EL element are greatly impaired, and the light emission life and the light emission efficiency of the organic EL element may be reduced. For example, in Patent Document 1, the temperature during the heat treatment is preferably equal to or lower than the glass transition temperature of the organic material of the organic EL element. Therefore, there is a demand for a configuration of an organic EL device or a heat treatment method in which the light emission lifetime and light emission efficiency of the organic EL element are not lowered in the heat treatment.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 An organic EL device according to this application example includes a substrate and an organic EL element that is provided on the substrate and in which an anode, an organic functional layer, and a cathode are sequentially stacked. The hole transport layer, the first light-emitting layer that emits light in a first color, the intermediate layer that adjusts the flow of electrons and holes, and the first color, which are sequentially disposed on the anode, A second light-emitting layer that emits light in a different second color, a third light-emitting layer that emits light in a third color different from the first color and the second color, and an alkali metal or an alkaline earth metal The organic EL element is heat-treated at a temperature higher than the lowest temperature among the glass transition temperatures of the respective materials constituting the organic functional layer. It is characterized by.

  The organic EL element according to this application example is heat-treated at a temperature higher than the lowest temperature among the glass transition temperatures of the respective materials constituting the organic functional layer. The inventors have conventionally determined that the temperature at which the organic EL element is subjected to the heat treatment is preferably a temperature lower than the glass transition temperature of the organic material, whereas the experiment shows that the heat treatment is performed at a temperature higher than the glass transition temperature. It has been found that the light emission lifetime and the light emission efficiency of the organic EL element are improved by performing the above. Therefore, according to this configuration, it is possible to provide an organic EL device in which the light emission lifetime and the light emission efficiency of the organic EL element are improved by performing heat treatment.

  Application Example 2 An organic EL device manufacturing method according to this application example includes a step of forming an organic EL element by sequentially stacking an anode, an organic functional layer, and a cathode on a substrate, and heating the organic EL element. And the step of forming the organic EL element includes, as the organic functional layer, a hole transport layer, a first light emitting layer that emits light of a first color, and an electron and hole Light emitting in a third color different from the first color and the second color, an intermediate layer for adjusting the flow, a second light emitting layer that emits light in a second color different from the first color A step of forming at least a third light-emitting layer and an electron transport layer including a diffusion layer in which an alkali metal or an alkaline earth metal is diffused, and in the step of heat-treating the organic EL element, the organic function The lowest temperature of the glass transition temperature of each material constituting the layer Remote wherein the heat treatment at high temperatures.

  In the method for manufacturing an organic EL element according to this application example, the organic EL element is subjected to heat treatment at a temperature higher than the lowest temperature among the glass transition temperatures of the respective materials constituting the organic functional layer. . Therefore, according to this method, it is possible to provide a method for manufacturing an organic EL device in which the light emission lifetime and the light emission efficiency of the organic EL element are improved as compared with the conventional method.

  Application Example 3 In the method of manufacturing an organic EL device according to the application example, in the step of heat-treating the organic EL element, the heat treatment may be performed by irradiating the organic EL element with laser light. Good.

  According to this method, the heat treatment is performed by irradiating the organic EL element with laser light in the heat treatment step. For this reason, the part which should be heat-processed can be heated intensively by irradiating a laser beam compared with the method of leaving an organic electroluminescent apparatus in the thermo-hygrostat kept at high temperature. For this reason, while raising an organic functional layer to predetermined temperature for a shorter time, it can return to room temperature for a shorter time. In addition, since the diffusion region can be formed in the diffusion layer of the intermediate layer or the electron transport layer by this heat treatment, the heat treatment for forming the diffusion region may not be performed separately. Thereby, since the time which the material which comprises an organic functional layer is exposed to high temperature becomes shorter, the deterioration of the characteristic of the organic EL element by temperature can be suppressed.

  Application Example 4 An electronic apparatus according to this application example includes the organic EL device described above or the organic EL device manufactured using the method for manufacturing the organic EL device described above. To do.

  According to this configuration, the electronic apparatus includes the organic EL device having a long lifetime and high light emission efficiency. For this reason, an electronic device with high reliability of the display portion can be provided.

1 is a schematic front view showing a configuration of an organic EL device according to a first embodiment. 1 is a block diagram showing an electrical configuration of an organic EL device according to a first embodiment. FIG. 3 is a cross-sectional view of a main part showing the structure of the organic EL device according to the first embodiment. 1 is a schematic cross-sectional view showing a configuration of an organic EL element according to a first embodiment. 3 is a flowchart showing a method for manufacturing the organic EL device according to the first embodiment. The figure explaining the heat processing method which concerns on 2nd Embodiment. FIG. 11 illustrates a mobile phone as an electronic apparatus. 3 is a graph comparing temporal changes in light emission luminance due to differences in heat treatment temperature of Example 1. FIG. The graph which shows the emitted light intensity in the organic electroluminescent apparatus of the conventional structure. The figure which shows the result of Example 2. FIG. The graph which shows the relationship between the heating temperature of Example 2, the thickness of a diffused layer, and the light emission lifetime. FIG. 6 shows the results of Example 3.

  The present embodiment will be described below with reference to the drawings. In each of the drawings to be referred to, in order to show the configuration in an easy-to-understand manner, the layer thickness, dimensional ratio, angle, and the like of each component are appropriately changed. In each drawing to be referred to, some elements, wiring, connection portions, and the like are omitted.

(First embodiment)
<Outline of organic EL device>
First, an outline of the organic EL device of the present embodiment will be described with reference to FIGS. 1, 2, and 3. FIG. 1 is a schematic front view showing the configuration of the organic EL device according to the first embodiment. FIG. 2 is a block diagram showing an electrical configuration of the organic EL device according to the first embodiment. FIG. 3 is a cross-sectional view of the main part showing the structure of the organic EL device according to the first embodiment. Specifically, FIG. 3 is a partial cross-sectional view taken along the line AA ′ of FIG.

  As shown in FIG. 1, the organic EL device 1 includes a light emitting region 4 having a substantially rectangular planar shape on an element substrate 20 as a substrate. The light emitting region 4 is a region that substantially contributes to light emission in the organic EL device 1. In the light emitting region 4, pixels 2 that emit red (R), green (G), or blue (B) light are arranged. The pixel 2 has, for example, a substantially rectangular planar shape. Note that the pixel 2 is actually very fine and is shown enlarged for the sake of illustration.

  The pixel 2 is a minimum unit of display of the organic EL device 1, and includes a pixel 2R that emits red light, a pixel 2G that emits green light, and a pixel 2B that emits blue light (hereinafter, referred to as “pixel 2B”). If the corresponding colors are not distinguished, they are also simply referred to as pixels 2). In the organic EL device 1, one pixel group is configured from the pixels 2R, 2G, and 2B, and various colors are displayed by appropriately changing the luminance of the pixels 2R, 2G, and 2B in each pixel group. Can do.

  The organic EL device 1 has an organic EL element 8 (see FIG. 2) provided on the element substrate 20 and arranged for each pixel 2. In addition, the organic EL device 1 includes a sealing substrate 40 that is disposed so as to overlap the element substrate 20 in a planar manner. The sealing substrate 40 is slightly smaller than the element substrate 20. The sealing substrate 40 is bonded to the element substrate 20 and seals the plurality of organic EL elements 8 provided on the element substrate 20.

  Two scanning line driving circuits 15 and one data line driving circuit 14 are provided in a portion of the element substrate 20 that protrudes in a frame shape from the sealing substrate 40. A flexible relay substrate 5 for connecting the scanning line driving circuit 15 and the data line driving circuit 14 to the external driving circuit is mounted on the terminal portion 20a of the element substrate 20.

  As shown in FIG. 2, the organic EL device 1 is an active matrix type organic EL device using a thin film transistor (hereinafter referred to as TFT) as a switching element. The organic EL device 1 includes a scanning line 16 provided on the element substrate 20, a signal line 17 extending in a direction intersecting the scanning line 16, and a power supply line 18 extending in parallel with the signal line 17. .

  In the organic EL device 1, the pixels 2 are arranged in a region surrounded by the scanning lines 16 and the signal lines 17. The pixels 2 are arranged in a matrix along the extending direction of the scanning lines 16 and the extending direction of the signal lines 17. The pixel 2 includes a switching TFT 11, a driving TFT 12, a storage capacitor 13, an anode 24, a cathode 26, and an organic functional layer 30. The organic functional layer 30 includes a light emitting layer that emits light when excited by recombination of holes and electrons injected by an electric field. The organic EL element 8 is configured by the anode 24, the organic functional layer 30, and the cathode 26.

  Connected to the signal line 17 is a data line driving circuit 14 including a shift register, a level shifter, a video line, and an analog switch. Further, a scanning line driving circuit 15 having a shift register and a level shifter is connected to the scanning line 16.

  In the organic EL device 1, when the scanning line 16 is driven and the switching TFT 11 is turned on, the image signal supplied via the signal line 17 is held in the holding capacitor 13 and driven according to the state of the holding capacitor 13. The on / off state of the TFT 12 is determined. When electrically connected to the power supply line 18 via the driving TFT 12, a drive current flows from the power supply line 18 to the anode 24, and further a current flows to the cathode 26 through the organic functional layer 30.

  The light emitting layer of the organic functional layer 30 emits light with a luminance corresponding to the amount of current flowing between the anode 24 and the cathode 26. In the present embodiment, the organic EL element 8 emits white light when the red (R), green (G), and blue (B) light emitting layers of the organic functional layer 30 emit light.

  As shown in FIG. 3, the organic EL device 1 includes an organic EL element 8 (an anode 24, an organic functional layer 30, and a cathode 26), a partition wall 25, a gas barrier layer 28, and a color filter 42 on an element substrate 20. And a sealing substrate 40. The element substrate 20 includes a substrate 10, a driving TFT 12 formed on the substrate 10, an interlayer insulating layer 22, and a planarizing layer 23. The organic EL device 1 is a top emission type in which light emitted from the organic EL element 8 is emitted to the sealing substrate 40 side. Details of the configuration of the organic EL element 8 will be described later.

Since the organic EL device 1 is a top emission type, the substrate 10 may use either a translucent material or an opaque material. Examples of the translucent material include glass, quartz, and resin (plastic and plastic film). Examples of the light-impermeable material include ceramics such as alumina, metal sheets such as stainless steel that have been subjected to insulation treatment such as surface oxidation, thermosetting resins and thermoplastic resins, and films thereof (plastic films). Can be given. The substrate 10 may be covered with a protective layer made of, for example, silicon oxide (SiO ₂ ).

  The driving TFT 12 is provided on the substrate 10 corresponding to the pixel 2. The driving TFT 12 includes a semiconductor film 12a, a gate insulating layer 21, a gate electrode 12g, a drain electrode 12d, and a source electrode 12s. A source region, a drain region, and a channel region are formed in the semiconductor film 12a. The semiconductor film 12 a is covered with the gate insulating layer 21. The gate electrode 12g is positioned so as to overlap the channel region of the semiconductor film 12a in plan view with the gate insulating layer 21 interposed therebetween.

  The interlayer insulating layer 22 covers the gate electrode 12g and the gate insulating layer 21. The drain electrode 12d is conductively connected to the drain region of the semiconductor film 12a through a contact hole provided in the interlayer insulating layer 22. Similarly, the source electrode 12s is conductively connected to the source region of the semiconductor film 12a through a contact hole. A protective layer made of, for example, silicon nitride (SiN) may be provided to cover the interlayer insulating layer 22, the drain electrode 12d, and the source electrode 12s.

  The planarization layer 23 is provided so as to cover the interlayer insulating layer 22, the drain electrode 12d, and the source electrode 12s. The planarization layer 23 has a substantially flat surface that does not reflect irregularities due to the drain electrode 12d, the source electrode 12s, and other wiring portions. The planarization layer 23 is made of, for example, an acrylic resin.

  The anode 24 is provided for each pixel 2 on the planarization layer 23. In order to further improve the reflectivity, for example, the anode 24 may be laminated on the reflective layer with an inorganic insulating layer or the like interposed therebetween. The anode 24 is conductively connected to the driving TFT 12 through a contact hole provided in the planarizing layer 23.

  The partition wall 25 is provided on the planarization layer 23. The partition wall 25 has an opening 25 a and partitions the region of the pixel 2. The partition wall 25 is formed so as to run on the peripheral edge portion of the anode 24 with a predetermined width along the periphery of the opening 25a. The thickness of the partition wall 25 is, for example, about 2 μm. Note that an inorganic insulating layer having an opening that is slightly smaller than the opening 25 a may be provided between the planarization layer 23 and the partition wall 25.

  The organic functional layer 30 is formed so as to cover the anode 24 and the partition wall 25. The cathode 26 is provided so as to cover the organic functional layer 30.

  The gas barrier layer 28 is provided so as to cover the cathode 26 (organic EL element 8). The gas barrier layer 28 has a function of hermetically sealing the organic EL element 8 and blocking oxygen and moisture. The gas barrier layer 28 is made of, for example, a silicon compound such as silicon oxide or silicon oxynitride in consideration of light transmittance, adhesion, water resistance, gas barrier properties, and the like. The thickness of the gas barrier layer 28 is preferably about 100 nm to 400 nm.

  Instead of the single gas barrier layer 28, a multilayer thin film protective layer including an electrode protective layer, an organic buffer layer, and a gas barrier layer may be provided. In that case, the electrode protective layer and the gas barrier layer are made of, for example, a silicon compound such as silicon oxide or silicon oxynitride, and the organic buffer layer is made of an organic material such as an epoxy resin. With such a configuration, it is possible to relieve uneven portions due to the partition walls 25 and the like, and to relieve stress generated by warping or volume expansion of the element substrate 20. In addition, since the organic EL element 8 can be sealed more airtightly, effects such as improvement in reliability of the organic EL device 1 and prevention of deterioration / deterioration (improvement in durability) can be obtained.

  The sealing substrate 40 is disposed so as to face the organic EL element 8 covered with the gas barrier layer 28. The sealing substrate 40 is made of a light-transmitting material, and is made of, for example, glass, quartz, resin (plastic, plastic film), or the like. The sealing substrate 40 is bonded to the element substrate 20 side by a sealing material (not shown) provided along the outer periphery of the sealing substrate 40. The space between the sealing substrate 40 and the element substrate 20 side (the gas barrier layer 28) is formed by, for example, an adhesive 41 made of translucent urethane resin, acrylic resin, epoxy resin, polyolefin resin, or the like. Filled.

  The color filter 42 is provided on the organic EL element 8 side of the sealing substrate 40. The color filter 42 includes a red color filter 42R, a green color filter 42G, and a blue color filter 42B (hereinafter, simply referred to as the color filter 42 when the corresponding colors are not distinguished). . The color filters 42R, 42G, and 42B are disposed corresponding to the pixels 2R, 2G, and 2B, and are provided so as to overlap the organic EL element 8 in a plane.

  The white light emitted by the organic EL element 8 passes through the color filters 42R, 42G, and 42B, so that light of three different colors R, G, and B is emitted from the pixels 2R, 2G, and 2B. Between the adjacent color filters 42R, 42G, and 42B, a light shielding layer 43 that partitions the color filters 42R, 42G, and 42B is provided. A flattening layer that covers the surfaces of the color filters 42R, 42G, and 42B and the light shielding layer 43 on the organic EL element 8 side and relaxes the unevenness of the surfaces may be provided.

  In the organic EL device 1, light emitted from the organic functional layer 30 to the cathode 26 side is emitted to the sealing substrate 40 side. Further, light emitted from the organic functional layer 30 to the anode 24 side is reflected by, for example, the anode 24 and is emitted to the sealing substrate 40 side.

  The organic EL device 1 is not limited to the active matrix type configuration, and may be a passive (simple) matrix type configuration. The organic EL device 1 is not limited to the top emission type, and may be a bottom emission type.

<Configuration of organic EL element>
Next, details of the configuration of the organic EL element will be described. FIG. 4 is a schematic cross-sectional view showing the configuration of the organic EL element according to the first embodiment. As shown in FIG. 4, the organic EL element 8 according to the first embodiment has a configuration in which an anode 24, an organic functional layer 30, and a cathode 26 are laminated. The organic functional layer 30 includes a hole injection layer 31, a hole transport layer 32, a red light emitting layer 33, an intermediate layer 34, a blue light emitting layer 35, a green light emitting layer 36, an electron transport layer 37, and an electron. The injection layer 38 and the injection layer 38 are stacked in this order.

  In the organic EL element 8, when a voltage is applied to the anode 24 and the cathode 26, electrons are supplied from the cathode 26 side to the light emitting layers of the red light emitting layer 33, the blue light emitting layer 35, and the green light emitting layer 36 ( And holes are supplied (injected) from the anode 24 side. In each light-emitting layer, holes and electrons recombine, and excitons (excitons) are generated by the energy released during the recombination. When excitons return to the ground state, energy (fluorescence or phosphorescence) is generated. Emits (emits light). Thereby, the organic EL element 8 emits white light.

(anode)
The anode 24 is an electrode that injects holes into the hole transport layer 32 through the hole injection layer 31. The material of the anode 24 is preferably a material that has translucency and has a large work function and excellent conductivity. Examples of the material of the anode 24 include ITO, IZO (Indium Zinc Oxide), In ₃ O ₃ , SnO ₂ , Sb-containing SnO ₂ , oxides such as Al-containing ZnO, Au, Pt, Ag, Cu or the like. An alloy etc. are mention | raise | lifted and it can use combining 1 type (s) or 2 or more types of these. The average thickness of the anode 24 is not particularly limited, but is preferably about 10 nm to 200 nm, and more preferably about 50 nm to 150 nm.

(cathode)
The cathode 26 is an electrode that injects electrons into the electron transport layer 37 through the electron injection layer 38. As the material of the cathode 26, a material having a small work function is preferable. Examples of the material of the cathode 26 include Li, Mg, Ca, Sr, La, Ce, Er, Eu, Sc, Y, Yb, Ag, Cu, Al, Cs, Rb, and alloys containing these. One or more of these can be used in combination.

  When an alloy is used as the material of the cathode 26, an alloy containing a stable metal element such as Ag, Al, or Cu, more specifically, an alloy such as MgAg, AlLi, or CuLi is preferable. By using such an alloy, the electron injection efficiency and stability of the cathode 26 can be improved. The average thickness of the cathode 26 is not particularly limited, but is preferably about 100 nm to 10000 nm, and more preferably about 200 nm to 500 nm.

(Hole injection layer)
The hole injection layer 31 has a function of improving the hole injection efficiency from the anode 24. The material of the hole injection layer 31 (hole injection material) is not particularly limited. For example, copper phthalocyanine or 4,4 ′, 4 ″ -tris (N, N-phenyl-3-methylphenylamino) Examples thereof include triphenylamine (m-MTDATA), N, N′-bis- (4-diphenylamino-phenyl) -N, N′-diphenyl-biphenyl-4-4′-diamine represented by the following chemical formula 1.

  The average thickness of the hole injection layer 31 is not particularly limited, but is preferably about 5 nm to 150 nm, and more preferably about 10 nm to 100 nm. The hole injection layer 31 may be omitted.

(Hole transport layer)
The hole transport layer 32 has a function of transporting holes injected from the anode 24 through the hole injection layer 31 to the red light emitting layer 33. As the material for the hole transport layer 32, various p-type polymer materials and various p-type low-molecular materials can be used alone or in combination. (1-naphthyl) -N, N′-diphenyl-1,1′-diphenyl-4,4′-diamine (α-NPD), N, N′-diphenyl-N, N′-bis (3-methylphenyl) ) -1,1'-diphenyl-4,4'-diamine (TPD) and other tetraarylbenzidine derivatives, tetraaryldiaminofluorene compounds or derivatives thereof (amine compounds), etc. Two or more kinds can be used in combination.

  The average thickness of the hole transport layer 32 is not particularly limited, but is preferably about 10 nm to 150 nm, and more preferably about 10 nm to 100 nm. The hole transport layer 32 can be omitted.

(Red light emitting layer)
The red light emitting layer 33 includes a red light emitting material. By using light of a relatively long wavelength such as red, a light emitting material having a relatively small energy level difference (band gap) between the lowest unoccupied molecular orbital (HOMO) and the highest occupied molecular orbital (LUMO) should be used. Can do. Thus, the light emitting material having a relatively small band gap easily captures holes and electrons and easily emits light. Therefore, by providing the red light-emitting layer 33 on the anode 24 side, the blue light-emitting layer 35 and the green light-emitting layer 36 that have a large band gap and are difficult to emit light can be set on the cathode 26 side, and each light-emitting layer can emit light in a balanced manner.

  In addition, when the material has a relatively small band gap, such as a red light emitting material, even when the density of electrons and holes in the red light emitting layer 33 is low, light can be suitably emitted. Although it does not specifically limit as a red luminescent material, Various red fluorescent materials and red phosphorescent materials can be used 1 type or in combination of 2 or more types.

  The red fluorescent material is not particularly limited as long as it emits red fluorescence. For example, perylene derivatives such as tetraaryldiindenoperylene derivatives shown in the following chemical formula 3, europium complexes, benzopyran derivatives, rhodamine derivatives, benzothios. Xanthene derivatives, porphyrin derivatives, Nile red, 2- (1,1-dimethylethyl) -6- (2- (2,3,6,7-tetrahydro-1,1,7,7-tetramethyl-1H, 5H) -Benzo (ij) quinolizin-9-yl) ethenyl) -4H-pyran-4H-ylidene) propanedinitrile (DCJTB), 4- (dicyanomethylene) -2-methyl-6- (p-dimethylaminostyryl)- Examples thereof include 4H-pyran (DCM).

  The red phosphorescent material is not particularly limited as long as it emits red phosphorescence, and examples thereof include metal complexes such as iridium, ruthenium, platinum, osmium, rhenium, and palladium. Among the ligands of these metal complexes, And those having at least one of phenylpyridine skeleton, bipyridyl skeleton, porphyrin skeleton and the like. More specifically, tris (1-phenylisoquinoline) iridium, bis [2- (2′-benzo [4,5-α] thienyl) pyridinate-N, C3 ′] iridium (acetylacetonate) (btp2Ir (acac )), 2,3,7,8,12,13,17,18-octaethyl-12H, 23H-porphyrin-platinum (II), bis [2- (2′-benzo [4,5-α] thienyl) Pyridinate-N, C3 ′] iridium, bis (2-phenylpyridine) iridium (acetylacetonate) and the like.

  Further, as a material of the red light emitting layer 33, a host material (first host material) using the above-described red light emitting material as a guest material may be used. The first host material recombines holes and electrons to generate excitons, and transfers the exciton energy to the red light-emitting material (Ferster movement or Dexter movement), thereby changing the red light-emitting material. It has a function to excite. Therefore, for example, the first host material can be doped with a red light-emitting material that is a guest material as a dopant.

  The first host material is not particularly limited as long as it exhibits the above-described function with respect to the red light emitting material to be used. For example, when the red light emitting material includes a red fluorescent material, for example, a distyrylarylene derivative , Naphthacene derivatives, anthracene derivatives as shown in the following chemical formula 4, anthracene derivatives such as 2-t-butyl-9,10-di (2-naphthyl) anthracene (TBADN), perylene derivatives, distyrylbenzene derivatives, distyrylamine Derivatives, quinolinolato metal complexes such as tris (8-quinolinolato) aluminum complex (Alq3), triarylamine derivatives such as tetraphenylamine tetramers, oxadiazole derivatives, and rubrene such as rubrene derivatives shown below And its derivatives, silole derivatives, dicarbazole derivatives Oligothiophene derivatives, benzopyran derivatives, triazole derivatives, benzoxazole derivatives, benzothiazole derivatives, quinoline derivatives, 4,4′-bis (2,2′-diphenylvinyl) biphenyl (DPVBi), and the like. Can be used alone or in combination of two or more.

  Further, when the red light emitting material includes a red phosphorescent material, examples of the first host material include 3-phenyl-4- (1′-naphthyl) -5-phenylcarbazole, 4,4′-N, N ′. -Carbazole derivatives, such as dicarbazole biphenyl (CBP), etc. are mention | raise | lifted, Among these, 1 type can be used individually or in combination of 2 or more types.

  When the first host material is included in the red light emitting layer 33, the content (dope amount) of the red light emitting material in the red light emitting layer 33 is preferably 0.01 wt% to 10 wt%, and 0.1 wt%. More preferably, it is ˜5 wt%. By setting the content of the red light emitting material in such a range, the light emission efficiency can be optimized, and the red light emitting layer 33 is formed while balancing the light emitting amount of the blue light emitting layer 35 and the green light emitting layer 36. Can emit light.

  Moreover, the average thickness of the red light emitting layer 33 is not particularly limited, but is preferably about 5 nm to 30 nm, and more preferably about 10 nm to 20 nm. Thereby, each light emitting layer of the organic EL element 8 can be made to emit light with good balance.

(Middle layer)
The intermediate layer 34 is provided between the red light emitting layer 33 and the blue light emitting layer 35 so as to be in contact therewith. The intermediate layer 34 has a function of adjusting the amount of electrons transported from the blue light emitting layer 35 to the red light emitting layer 33. The intermediate layer 34 has a function of adjusting the amount of holes transported from the red light emitting layer 33 to the blue light emitting layer 35. Further, the intermediate layer 34 has a function of preventing exciton energy from moving between the red light emitting layer 33 and the blue light emitting layer 35. With this function, the red light emitting layer 33 and the blue light emitting layer 35 can each emit light efficiently. As a result, each light emitting layer can emit light in a well-balanced manner, and the organic EL element 8 can emit light in a desired color, for example, white, and the light emission efficiency and life of the organic EL element 8 can be improved. Can be planned.

  The average thickness of the intermediate layer 34 is, for example, about 1 nm to 60 nm. By providing the relatively thick intermediate layer 34 in this way, current is prevented from flowing through the organic EL element 8 when a weak voltage is applied between the anode 24 and the cathode 26. For this reason, when the driving of the organic EL element 8 is released, a black floating phenomenon that occurs when a weak voltage is generated between the anode 24 and the cathode 26 and a current flows through the organic EL element 8 is prevented. Further, when the average thickness is equal to or less than the upper limit value, the amount of electrons and holes transported in the intermediate layer 34 is reduced, and the light emission efficiency is prevented from being lowered.

  By providing the intermediate layer 34 as described above, the organic EL element 8 has the black floating phenomenon suppressed while maintaining excellent light emission efficiency and light emission balance. Further, since the intermediate layer 34 is relatively thick as described above, it has excellent durability. Furthermore, since the emission balance is excellent, it is possible to prevent the holes and electrons from concentrating on the specific light emitting layer and deteriorating the light emitting layer. As described above, the light emission life of the organic EL element 8 as a whole can be extended.

  On the other hand, when the average thickness of the intermediate layer 34 is less than the lower limit value, when a weak voltage is applied between the anode 24 and the cathode 26, current easily flows through the organic EL element 8, and black The floating phenomenon cannot be suppressed. On the other hand, when the average thickness of the intermediate layer 34 exceeds the upper limit, the light emission efficiency of the organic EL element 8 as a whole is drastically reduced. The average thickness of the intermediate layer 34 may be in the range as described above, but in order to obtain a more remarkable effect, it is preferably 1 nm to 60 nm, and more preferably 3 nm to 20 nm.

  The material of the intermediate layer 34 is not particularly limited as long as the intermediate layer 34 can exhibit the function as described above. For example, a material having a function of transporting holes (hole transport material) A material having a function of transporting electrons (electron transport material) or the like can be used, and a hole transport material is preferably used. In general, holes have a lower mobility than electrons, but the intermediate layer 34 contains a hole transport material, so that holes are smoothly transferred from the intermediate layer 34 to the blue light emitting layer 35, and each light emission. The layer becomes easy to emit light in a balanced manner, and the organic EL element 8 can emit light in a target color, for example, white and has excellent luminous efficiency.

  The hole transport material used for the intermediate layer 34 is not particularly limited as long as the intermediate layer 34 exhibits the function as described above. For example, the hole transport material has an amine skeleton in the hole transport material described above. An amine material can be used, but a benzidine amine derivative is preferably used. In particular, among benzidine-based amine derivatives, the amine-based material used for the intermediate layer 34 is preferably a material into which two or more aromatic ring groups are introduced, and a tetraarylbenzidine derivative is more preferable. Examples of such benzidine-based amine derivatives include N, N′-bis (1-naphthyl) -N, N′-diphenyl [1,1′-biphenyl] -4,4′- Examples include diamine (α-NPD), N, N, N ′, N′-tetranaphthyl-benzidine (TNB), and the like.

  Such an amine-based material is generally excellent in hole transportability. Therefore, holes can be smoothly transferred from the red light emitting layer 33 to the blue light emitting layer 35 via the intermediate layer 34. In addition, since the holes are sufficiently supplied to the blue light emitting layer 35 that is least likely to emit light among the light emitting layers, each light emission is performed even when the voltage applied between the anode 24 and the cathode 26 is changed. The light emission balance of the layer is difficult to change.

  In addition to the hole transport material, the intermediate layer 34 preferably includes an electron transport material at the same time. Thereby, the intermediate layer 34 has an electron transport property and a hole transport property. That is, the intermediate layer 34 has a bipolar property. When the intermediate layer 34 is bipolar, holes are smoothly transferred from the red light emitting layer 33 through the intermediate layer 34 to the blue light emitting layer 35, and the red light emitting layer 33 is transmitted from the blue light emitting layer 35 through the intermediate layer 34. Electrons can be transferred smoothly to As a result, electrons and holes can be efficiently injected into the red light emitting layer 33 and the blue light emitting layer 35 to emit light.

  Further, by having bipolar properties, the intermediate layer 34 is excellent in resistance to carriers (electrons and holes). For this reason, even if electrons and holes are recombined in the intermediate layer 34 to generate excitons, the deterioration of the intermediate layer 34 can be prevented or suppressed. Thereby, the deterioration by the exciton of the intermediate layer 34 can be prevented or suppressed, and as a result, the durability (light emission life) of the organic EL element 8 can be made excellent.

  The electron transport material that can be used for the intermediate layer 34 is not particularly limited as long as the intermediate layer 34 exhibits the functions described above, and for example, an acene-based material can be used. Since the acene-based material has excellent electron transport properties, electrons can be smoothly transferred from the blue light emitting layer 35 to the red light emitting layer 33 through the intermediate layer 34. In addition, since the acene-based material is excellent in exciton resistance, deterioration of the intermediate layer 34 due to excitons can be prevented or suppressed, and as a result, the durability of the organic EL element 8 can be improved.

  Examples of such acene-based materials include naphthalene derivatives, anthracene derivatives, tetracene derivatives, pentacene derivatives, hexacene derivatives, heptacene derivatives, and the like, and one or more of these can be used in combination. , Naphthalene derivatives and anthracene derivatives are preferably used, and anthracene derivatives are more preferably used. Examples of the anthracene derivative include an anthracene derivative represented by Chemical Formula 4 and 2-t-butyl-9,10-di-2-naphthylanthracene (TBADN) represented by Chemical Formula 6 below.

  When the hole transport material and the electron transport material are simultaneously contained in the intermediate layer 34, the content of the hole transport material in the intermediate layer 34 is not particularly limited, but is preferably 5 wt% to 95 wt%, and 7 wt% % To 90 wt% is more preferable, and 10 wt% to 85 wt% is even more preferable. The content of the acene-based material in the intermediate layer 34 is not particularly limited, but is preferably 10 wt% to 70 wt%, more preferably 15 wt% to 60 wt%, and 20 wt% to 55 wt%. More preferably.

  When the content of the hole transport material in the intermediate layer 34 is CH [wt%] and the content of the electron transport material is CE [wt%], the relationship of 0.5 ≦ CH / CE ≦ 20 may be satisfied. Preferably, it is more preferable to satisfy the relationship of 1.0 ≦ CH / CE ≦ 10. Thereby, it is possible to inject electrons and holes into the red light emitting layer 33 and the blue light emitting layer 35, respectively, while making the intermediate layer 34 more excellent in resistance to carriers and excitons. The light emission balance of the light emitting layer can be made more excellent. Further, even when the voltage applied to the organic EL element 8 changes, the light emission balance of each light emitting layer is more difficult to change.

(Blue light emitting layer)
The blue light emitting layer 35 includes a blue light emitting material. By using light having a relatively short wavelength such as blue, a light emitting material having a relatively large band gap can be used. As described above, a light emitting material having a relatively large band gap is less likely to capture holes and electrons than a light emitting material having a relatively small band gap. However, by disposing the blue light emitting layer 35 in such a position, holes and electrons are sufficiently supplied to the blue light emitting layer 35, and the blue light emitting layer 35 can sufficiently emit light.

  In addition, the energy of excitons generated by recombination of electrons and holes near the interface between the intermediate layer 34 and the blue light emitting layer 35 is efficiently used for light emission of the blue light emitting layer 35. For this reason, each light emitting layer can emit light with good balance. Further, even when the voltage applied to the organic EL element 8 is weak or when the voltage changes, the light emission balance of each light emitting layer is difficult to change. The blue light emitting material is not particularly limited, and various blue fluorescent materials and blue phosphorescent materials can be used alone or in combination of two or more.

  The blue fluorescent material is not particularly limited as long as it emits blue fluorescence. For example, a distyrylamine derivative such as a distyryldiamine compound represented by the following chemical formula 7, a fluoranthene derivative, a pyrene derivative, perylene, and perylene Derivatives, anthracene derivatives, benzoxazole derivatives, benzothiazole derivatives, benzimidazole derivatives, chrysene derivatives, phenanthrene derivatives, distyrylbenzene derivatives, tetraphenylbutadiene, 4,4′-bis (9-ethyl-3-carbazovinylene) -1, 1′-biphenyl (BCzVBi), poly [(9.9-dioctylfluorene-2,7-diyl) -co- (2,5-dimethoxybenzene-1,4-diyl)], poly [(9,9- Dihexyloxyfluorene-2,7-diyl) -o Toco- (2-methoxy-5- {2-ethoxyhexyloxy} phenylene-1,4-diyl)], poly [(9,9-dioctylfluorene-2,7-diyl) -co- (ethylnyl) Benzene)] and the like, and one of these may be used alone or in combination of two or more.

  The blue phosphorescent material is not particularly limited as long as it emits blue phosphorescence, and examples thereof include metal complexes such as iridium, ruthenium, platinum, osmium, rhenium, and palladium. More specifically, bis [4,6-difluorophenylpyridinate-N, C2 ′]-picolinate-iridium, tris [2- (2,4-difluorophenyl) pyridinate-N, C2 ′] iridium, bis [2- (3,5-trifluoromethyl) pyridinate-N, C2 ′]-picolinate-iridium, bis (4,6-difluorophenylpyridinate-N, C2 ′) iridium (acetylacetonate) .

  In addition to the blue light emitting material as described above, a host material (second host material) using the blue light emitting material as a guest material may be used as the material of the blue light emitting layer 35. As the second host material that can be used for the blue light emitting layer 35, the same host material as the first host material of the red light emitting layer 33 described above can be used.

  When the blue light emitting layer 35 includes the second host material, the content (dope amount) of the blue light emitting material in the blue light emitting layer 35 is preferably 0.01 wt% to 20 wt%, and 1 wt% to 15 wt%. It is more preferable that By making the content of the blue light emitting material within such a range, the light emission efficiency can be optimized, and the blue light emitting layer is balanced with the light emitting amount of the red light emitting layer 33 and the green light emitting layer 36 described later. 35 can emit light.

  Moreover, although the average thickness of the blue light emitting layer 35 is not specifically limited, It is preferable that it is about 10 nm-30 nm, and it is more preferable that it is about 12 nm-20 nm.

(Green light emitting layer)
The green light emitting layer 36 includes a green light emitting material. The green light emitting material is not particularly limited, and various green fluorescent materials and green phosphorescent materials can be used alone or in combination of two or more.

  The green fluorescent material is not particularly limited as long as it emits green fluorescence. For example, quinacridone such as a coumarin derivative, a quinacridone derivative represented by the following chemical formula 8 and derivatives thereof, 9,10-bis [(9-ethyl- 3-carbazole) -vinylenyl] -anthracene, poly (9,9-dihexyl-2,7-vinylenefluorenylene), poly [(9,9-dioctylfluorene-2,7-diyl) -co- (1, 4-diphenylene-vinylene-2-methoxy-5- {2-ethylhexyloxy} benzene)], poly [(9,9-dioctyl-2,7-divinylenefluorenylene) -ortho-co- (2-methoxy -5- (2-ethoxylhexyloxy) -1,4-phenylene)], etc., one of which is used alone or two or more of them are combined It can also be used.

  The green phosphorescent material is not particularly limited as long as it emits green phosphorescence, and examples thereof include metal complexes such as iridium, ruthenium, platinum, osmium, rhenium, and palladium. Among these, at least one of the ligands of these metal complexes preferably has a phenylpyridine skeleton, a bipyridyl skeleton, a porphyrin skeleton, or the like. More specifically, fac-tris (2-phenylpyridine) iridium (Ir (ppy) 3), bis (2-phenylpyridinate-N, C2 ′) iridium (acetylacetonate), fac-tris [5 -Fluoro-2- (5-trifluoromethyl-2-pyridine) phenyl-C, N] iridium.

  Further, the green light emitting layer 36 may contain a host material (third host material). As the third host material of the green light emitting layer 36, the same host material as the first host material of the red light emitting layer 33 described above can be used.

  When the green light emitting layer 36 includes the third host material, the content (dope amount) of the green light emitting material in the green light emitting layer 36 is preferably 0.01 wt% to 20 wt%, and 1 wt% to 15 wt%. It is more preferable that By setting the content of the green light emitting material within such a range, the light emission efficiency can be optimized, and the green light emitting layer 36 can be formed while balancing the light emitting amount of the red light emitting layer 33 and the blue light emitting layer 35. Can emit light. Further, the average thickness of the green light emitting layer 36 is not particularly limited, but is preferably about 5 nm to 20 nm, and more preferably about 8 nm to 15 nm.

(Electron transport layer)
The electron transport layer 37 has a function of transporting electrons injected from the cathode 26 through the electron injection layer 38 to the green light emitting layer 36. The electron transport layer 37 is composed of two layers of a base layer 37a and a diffusion layer 37b. The base layer 37 a is disposed on the side in contact with the green light emitting layer 36, and the diffusion layer 37 b is disposed on the side in contact with the electron injection layer 38.

  The base layer 37a is preferably made of an electron transport material having a lower electron mobility than the diffusion layer 37b. Examples of the material (electron transport material) of the base layer 37a include quinolines such as organometallic complexes having 8-quinolinol or a derivative thereof such as tris (8-quinolinolato) aluminum (Alq3) shown in the following chemical formula 9 as a ligand. Derivatives, perylene derivatives, pyridine derivatives, pyrimidine derivatives, quinoxaline derivatives, diphenylquinone derivatives, nitro-substituted fluorene derivatives, and the like can be used, and one or more of these can be used in combination.

  The average thickness of the base layer 37a is not particularly limited, but is preferably about 0.5 nm to 100 nm, and more preferably about 1 nm to 50 nm.

  The diffusion layer 37b is preferably made of an electron transport material having a higher electron mobility than the base layer 37a. Examples of the material (electron transport material) of the diffusion layer 37b include an oxadiazole derivative (tBu-PBD) shown in the following chemical formula 10 and a silole derivative (ET4) shown in the chemical formula 11 below. Species or a combination of two or more can be used. For example, alkali metal or alkaline earth metal such as Li, Na, Cs, Mg, Ca, Sr, and Ba is diffused in the diffusion layer 37b.

  The average thickness of the diffusion layer 37b is not particularly limited, but is preferably about 5 nm to 70 nm, and more preferably about 7 nm to 60 nm.

  Since the electron transport layer 37 has the diffusion layer 37b on the side in contact with the electron injection layer 38, the alkali metal or alkaline earth metal contained in the electron injection layer 38 has a lower electron mobility than the diffusion layer 37b. Difficult to diffuse into the base layer 37a made of the electron transport material. For this reason, diffusion of these alkali metals and alkaline earth metals into the green light emitting layer 36 is suppressed. Thereby, since the green light emitting layer 36 can emit light efficiently, the light emission efficiency and the light emission lifetime of the organic EL element 8 can be improved.

(Electron injection layer)
The electron injection layer 38 has a function of improving the efficiency of electron injection from the cathode 26. Examples of the material (electron injection material) of the electron injection layer 38 include various inorganic insulating materials and various inorganic semiconductor materials.

  Examples of such inorganic insulating materials include alkali metal chalcogenides (oxides, sulfides, selenides, tellurides), alkaline earth metal chalcogenides, alkali metal halides, and alkaline earth metal halides. Of these, one or two or more of these can be used in combination. By forming the electron injection layer using these as main materials, the electron injection property can be further improved. In particular, alkali metal compounds (alkali metal chalcogenides, alkali metal halides, etc.) have a very small work function, and the organic EL element 8 can obtain high luminance by forming the electron injection layer 38 using the work function. It becomes.

Examples of the alkali metal chalcogenide include Li ₂ O, LiO, Na ₂ S, Na ₂ Se, NaO and the like. Examples of the alkaline earth metal chalcogenide include CaO, BaO, SrO, BeO, BaS, MgO, and CaSe. Examples of the alkali metal halide include CsF, LiF, NaF, KF, LiCl, KCl, and NaCl. Examples of the alkaline earth metal halide include CaF ₂ , BaF ₂ , SrF ₂ , MgF ₂ , and BeF ₂ .

  In addition, as the inorganic semiconductor material, for example, an oxide including at least one element of Li, Na, Ba, Ca, Sr, Yb, Al, Ga, In, Cd, Mg, Si, Ta, Sb, and Zn Nitride or oxynitride can be used, and one or more of these can be used in combination.

  The average thickness of the electron injection layer 38 is not particularly limited, but is preferably about 0.1 nm to 1000 nm, more preferably about 0.2 nm to 100 nm, and about 0.2 nm to 50 nm. Further preferred.

  In addition, although the above-mentioned organic EL element 8 had the three light emitting layers in the organic functional layer 30, the light emitting layer may be two layers or four layers or more. The emission color of the light emitting layer is not limited to R, G, and B described above. Moreover, the intermediate | middle layer 34 should just be provided between the at least 1 interlayer of light emitting layers, and may have an intermediate | middle layer of two or more layers.

<Method for manufacturing organic EL device>
Next, a method for manufacturing the organic EL device according to the first embodiment will be described. FIG. 5 is a flowchart showing a method for manufacturing the organic EL device according to the first embodiment.

  As shown in FIG. 5, the manufacturing method of the organic EL device includes a substrate preparation step S10, an organic EL element formation step S20, a sealing step S40, and a heat treatment step S50.

  In the substrate preparation step S10, the driving TFT 12, the interlayer insulating layer 22, and the planarization layer 23 are formed on the substrate 10 by a known method to prepare the element substrate 20.

  Next, organic EL element formation process S20 is performed. The organic EL element forming step S20 includes an anode forming step S21, a hole injection layer forming step S22, a hole transport layer forming step S23, a red light emitting layer forming step S24, an intermediate layer forming step S25, and a blue light emitting layer. It includes a formation step S26, a green light emitting layer formation step S27, an electron transport layer formation step S28, an electron injection layer formation step S29, and a cathode formation step S30.

  In the anode forming step S <b> 21, the anode 24 is formed on the element substrate 20. The anode 24 is formed by, for example, chemical vapor deposition (CVD) methods such as plasma CVD and thermal CVD, dry plating methods such as vacuum deposition, wet plating methods such as electrolytic plating, thermal spraying methods, sol-gel methods, MOD methods, metal foils. It can be formed by using, for example, bonding.

  Subsequently, in the hole injection layer forming step S <b> 22, the hole injection layer 31 is formed on the anode 24. The hole injection layer 31 can be formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering, or the like.

  The hole injection layer 31 is dried (desolvent or desolvent) after supplying a hole injection layer forming material obtained by, for example, dissolving a hole injection material in a solvent or dispersing in a dispersion medium onto the anode 24. It can also be formed by using a dispersion medium. As a method for supplying the hole injection layer forming material, for example, various coating methods such as a spin coating method, a roll coating method, and an ink jet printing method can be used. By using such a coating method, the hole injection layer 31 can be formed relatively easily. Examples of the solvent or dispersion medium used for the preparation of the hole injection layer forming material include various inorganic solvents, various organic solvents, or mixed solvents containing these.

  The drying can be performed, for example, by standing in an atmospheric pressure or a reduced pressure atmosphere, heat treatment, or blowing an inert gas. Prior to this step, the upper surface of the anode 24 may be subjected to oxygen plasma treatment. Thereby, it is possible to impart lyophilicity to the upper surface of the anode 24, remove (clean) organic substances adhering to the upper surface of the anode 24, adjust the work function near the upper surface of the anode 24, and the like. .

  Here, as conditions for the oxygen plasma treatment, for example, the plasma power is about 100 W to 800 W, the oxygen gas flow rate is about 50 mL / min to 100 mL / min, and the conveying speed of the member to be processed (anode 24) is 0.5 mm / sec to 10 mm / min. It is preferable to set the temperature of the element substrate 20 to about 70 ° C. to 90 ° C. for about sec.

  Subsequently, in the hole transport layer forming step S <b> 23, the hole transport layer 32 is formed on the hole injection layer 31. The hole transport layer 32 can be formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering, or the like. Further, by supplying a hole transport layer forming material obtained by dissolving a hole transport material in a solvent or dispersing in a dispersion medium onto the hole injection layer 31, drying (desolvation or dedispersion medium) is performed. Can also be formed.

  Subsequently, in the red light emitting layer forming step S <b> 24, the red light emitting layer 33 is formed on the hole transport layer 32. The red light emitting layer 33 can be formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering, or the like.

  Subsequently, in the intermediate layer forming step S <b> 25, the intermediate layer 34 is formed on the red light emitting layer 33. The intermediate layer 34 can be formed, for example, by a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering.

  Subsequently, in the blue light emitting layer forming step S <b> 26, the blue light emitting layer 35 is formed on the intermediate layer 34. The blue light emitting layer 35 can be formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering.

  Subsequently, in the green light emitting layer forming step S <b> 27, the green light emitting layer 36 is formed on the blue light emitting layer 35. The green light emitting layer 36 can be formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum evaporation or sputtering.

  Subsequently, in the electron transport layer forming step S28, the base layer 37a and the diffusion layer 37b are stacked on the green light emitting layer 36 to form the electron transport layer 37. The electron transport layer 37 can be formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering. The electron transport layer 37 is dried (desolvent or dedispersed) after supplying an electron transport layer forming material obtained by, for example, dissolving an electron transport material in a solvent or dispersing in a dispersion medium onto the green light emitting layer 36. It can also be formed by the medium.

  Subsequently, in the electron injection layer forming step S <b> 29, the electron injection layer 38 is formed on the electron transport layer 37. In the case where an inorganic material is used as the constituent material of the electron injection layer 38, the electron injection layer 38 is formed by, for example, a vapor phase process using a CVD method, a dry plating method such as vacuum deposition or sputtering, or application and baking of inorganic fine particle ink. Etc. can be used.

  Subsequently, in the cathode formation step S <b> 30, the cathode 26 is formed on the electron injection layer 38. The cathode 26 can be formed by using, for example, a vacuum deposition method, a sputtering method, joining of metal foils, application and firing of metal fine particle ink, or the like. The organic EL element 8 formed on the element substrate 20 is obtained through the organic EL element forming step S20.

  Next, in the sealing step S40, first, the gas barrier layer 28 is formed so as to cover the organic EL element 8 (cathode 26). The gas barrier layer 28 can be formed using, for example, an ion plating method, a CVD method, or the like. Subsequently, the sealing substrate 40 is bonded to the element substrate 20, and the space between the sealing substrate 40 and the gas barrier layer 28 is filled with the adhesive 41. The sealing substrate 40 is disposed so that the surface on which the color filter 42 is provided faces the organic EL element 8. Thereby, the organic EL device 1 is obtained.

  Next, in the heat treatment step S50, the organic EL device 1 (organic EL element 8) is subjected to heat treatment. The temperature of the heat treatment is set higher than the lowest temperature among the glass transition temperatures (Tg) of the respective materials constituting the organic functional layer 30 of the organic EL element 8. In the organic EL element 8 of the present embodiment, the lowest Tg among the materials constituting the organic functional layer 30 is, for example, about 80 ° C. On the other hand, the temperature of the heat treatment is preferably about 100 ° C. to 120 ° C., and more preferably about 120 ° C.

  As the heating method in the heat treatment step S50, for example, the organic EL device 1 is left in a constant temperature and humidity chamber maintained at a predetermined temperature. The heating time is preferably set to a time until the temperature of the organic functional layer 30 reaches the above temperature. In the heat treatment step S50, it is only necessary that the temperature of the organic functional layer 30 reaches the above temperature by the heat treatment, and maintaining the temperature for a long time after reaching the above temperature deteriorates the characteristics of the organic functional layer 30. This is not preferable because it may cause

  By performing this heat treatment step S50, the light emission lifetime and the light emission efficiency of the organic EL element 8 are improved as shown in the examples described later. Thereby, the organic EL device 1 in which the light emission lifetime and the light emission efficiency of the organic EL element 8 are improved as compared with the related art can be provided.

(Second Embodiment)
Next, a second embodiment will be described. In the second embodiment, the configuration of the organic EL device is the same as that of the first embodiment, and the manufacturing method of the organic EL device includes the same steps, but the heating method in the heat treatment step S50 is different. ing. More specifically, the organic EL device manufacturing method according to the second embodiment is different in that the heat treatment of the organic EL device 1 is performed by irradiating laser light in the heat treatment step S50.

  An example of the heat treatment method in the heat treatment step S50 of the method for manufacturing the organic EL device according to the second embodiment will be described. FIG. 6 is a diagram illustrating a heat treatment method according to the second embodiment.

  The heat treatment step S50 is performed, for example, in the chamber 100 shown in FIG. The chamber 100 is formed of, for example, a metal such as aluminum, an alloy, or the like, and is configured to be able to seal the internal space. The inside of the chamber 100 is depressurized by a vacuum pump (not shown). The chamber 100 is provided with a light introduction window 102 made of, for example, glass. A stage 110 on which the organic EL device 1 that performs heat treatment is placed is disposed in the chamber 100. The stage 110 is configured to be movable in the direction of the arrow in FIG. 6 with the organic EL device 1 placed thereon.

  A laser light source 120 is disposed outside the light introduction window 102 of the chamber 100. The laser light source 120 generates laser light L. The laser light L generated by the laser light source 120 is applied to the surface of the organic EL device 1 placed on the stage 110 through the light introduction window 102. Heat treatment is performed by the laser light L.

  In addition, the surface scan of the laser beam L with respect to the organic EL device 1 can be performed by moving the stage 110. There is no limitation in particular as the light source 120, According to the kind of thin film formed on the organic EL apparatus 1 which is a to-be-irradiated body, it can select from a well-known laser light source suitably.

  Compared with the method of leaving the organic EL device 1 in the constant temperature and humidity chamber of the first embodiment by irradiating the organic EL device 1 with laser light and performing the heat treatment, the portion to be heat-treated is concentrated. Can be heated. For this reason, the organic functional layer 30 can be raised to a predetermined temperature in a shorter time and returned to room temperature in a shorter time. Further, since the diffusion region can be formed in the intermediate layer 34 or the diffusion layer 37b of the electron transport layer 37 by this heat treatment, it is not necessary to separately perform the heat treatment for forming the diffusion region. Thereby, since the time which the material which comprises the organic functional layer 30 is exposed to high temperature becomes shorter, the deterioration of the characteristic of the organic EL element 8 by temperature can be suppressed.

  Therefore, according to the manufacturing method of the organic EL device according to the second embodiment, it is possible to provide the organic EL device 1 in which the light emission lifetime and the light emission efficiency of the organic EL element 8 are further improved. In the method for manufacturing the organic EL device according to the second embodiment, the heat treatment step S50 may be performed before the sealing step S40.

<Electronic equipment>
The above-described organic EL device 1 can be used by being mounted on a mobile phone 500 as an electronic device, for example, as shown in FIG. The mobile phone 500 includes the organic EL device 1 in the display unit 502. With this configuration, the mobile phone 500 including the display portion 502 can perform bright display with a longer lifetime.

  Further, the electronic device may be an electronic book, a personal computer, a digital still camera, a viewfinder type or a monitor direct-view type video tape recorder, an in-vehicle monitor of a car navigation device, and the like.

  Furthermore, the organic EL device 1 of the present invention can also be used as a light source or illumination device for a device other than a display device, for example, an exposure head of a printer head.

  Next, examples of the present invention will be described.

Example 1
<1. Relationship between heat treatment temperature of organic EL element and emission lifetime>
First, as Example 1, an organic EL device having the configuration of the organic EL device 1 according to the first embodiment was manufactured by the method for manufacturing an organic EL device according to the first embodiment. The specific configuration of the organic functional layer in the organic EL device of Example 1 is as follows.

  The hole injection layer 31 was formed with a thickness of 30 nm using m-MTDATA as a material. The hole transport layer 32 was formed with a thickness of 20 nm using α-NPD as a material. The red light emitting layer 33 was formed with a thickness of 5 nm using rubrene as a host material and a perylene derivative as a dopant. The intermediate layer 34 was formed with a thickness of 5 nm using α-NPD as a material. The blue light emitting layer 35 was formed with a thickness of 12 nm using ADN (made by Idemitsu Kosan Co., Ltd.) as the host material and BD142 (made by Idemitsu Kosan Co., Ltd.) as the dopant. The green light emitting layer 36 was formed with a thickness of 8 nm using Alq3 as the host material and quinacridone as the dopant. In the electron transport layer 37, the base layer 37a was formed with a thickness of 20 nm using Alq3 as a material, and the diffusion layer 37b was formed with a thickness of 20 nm using quinacridone as a material. The electron injection layer 38 was formed with a thickness of 1 nm using LiF as a material.

Then, the experiment which heat-processes the organic EL apparatus of the said Example 1 at different temperature was conducted. FIG. 8 is a graph comparing changes in light emission luminance over time due to differences in heat treatment temperature in Example 1. Specifically, in the heat treatment step S50 according to the first embodiment, the organic EL device of Example 1 was subjected to heat treatment at different temperatures of 95 ° C, 105 ° C, 110 ° C, 115 ° C, and 120 ° C. is there. The heating time was 14 hours at 95 ° C. and 4 hours at other temperatures. In FIG. 8, the horizontal axis represents the light emission time when the organic EL device is driven at 400 mA / cm ² , and the vertical axis represents the ratio of light emission luminance when the light emission luminance at the initial time is 1.

  As shown in FIG. 8, in the organic EL device of Example 1, based on the case of heating at 95 ° C., the higher the heat treatment temperature, the longer the time for light emission with the same light emission luminance. From this result, it can be seen that in the organic EL device 1 of Example 1, if the temperature is at least 120 ° C., the higher the heat treatment temperature, the longer the light emission lifetime.

  FIG. 9 is a graph showing light emission intensity in an organic EL device having a conventional configuration. Specifically, as an organic EL device having a conventional configuration, an organic EL device having the same configuration as that of the organic EL device of Example 1 is used except that the diffusion layer 37b in the electron transport layer 37 and the intermediate layer 34 are not included. Thus, the emission intensity is compared between the initial time point and the time point when the heat treatment is performed at different temperatures of 115 ° C. and 120 ° C. The heating time was 4 hours for both 115 ° C. and 120 ° C. In FIG. 9, the horizontal axis is the emission wavelength, and the vertical axis is the emission intensity.

  As shown in FIG. 9, it can be seen that the higher the heating temperature is, the lower the light emission intensity of the organic EL device, that is, the light emission lifetime is lower than the initial time point. The temperatures of 115 ° C. and 120 ° C. are higher than the lowest temperature among the glass transition temperatures of the materials constituting the organic functional layer, and “the temperature during the heat treatment is the organic material of the organic EL element” in Patent Document 1. It is a result corresponding to the description that "the glass transition temperature or lower of is preferable."

  On the other hand, in the heat treatment experiment of this example shown in FIG. 8, the emission life is longer when heated at a temperature higher than the lowest temperature among the glass transition temperatures of the materials constituting the organic functional layer. The result was contrary to the idea. The reason why the result contrary to the conventional idea is obtained is considered that the configuration of the organic functional layer including the electron transport layer 37 including the diffusion layer 37b and the intermediate layer is involved. Therefore, further experiments were performed with different configurations such as the thickness of the diffusion layer and the intermediate layer of the electron transport layer in the organic functional layer.

(Example 2)
<2. Relationship between diffusion layer thickness and emission lifetime and emission efficiency in electron transport layer>
Next, as Example 2, an organic EL device was manufactured by changing the thickness of the diffusion layer 37 b in the electron transport layer 37. The specific configuration of the organic functional layer in the organic EL device of Example 2 is as follows.

  The hole injection layer 31 was formed with a thickness of 30 nm using HI406 (made by Idemitsu Kosan Co., Ltd.) as a material. The hole transport layer 32 was formed with a thickness of 20 nm using α-NPD as a material. The red light emitting layer 33 was formed with a thickness of 5 nm using BH215 (made by Idemitsu Kosan Co., Ltd.) as the host material and RD001 (made by Idemitsu Kosan Co., Ltd.) as the dopant. The intermediate layer 34 was formed with a thickness of 5 nm using α-NPD as a material. The blue light emitting layer 35 was formed with a thickness of 12 nm using BH215 (made by Idemitsu Kosan Co., Ltd.) as the host material and BD102 (made by Idemitsu Kosan Co., Ltd.) as the dopant. The green light emitting layer 36 was formed with a thickness of 8 nm using BH215 (made by Idemitsu Kosan Co., Ltd.) as the host material and GD206 (made by Idemitsu Kosan Co., Ltd.) as the dopant. The base layer 37a of the electron transport layer 37 was formed with a thickness of 10 nm using Alq3 as a material, and the diffusion layer 37b was formed using tBu-PBD as a material with different thicknesses. The electron injection layer 38 was formed with a thickness of 1 nm using LiF as a material.

  Furthermore, in Example 2, the heat treatment step S50 according to the second embodiment was applied as a method for performing the heat treatment of the organic EL device. More specifically, heat treatment was performed by laser light irradiation, and the heat treatment temperature was 120 ° C. Further, as Comparative Example 1, by using an organic EL device having the same configuration as that of Example 2 in which the diffusion layer 37b of the electron transport layer 37 was formed with a thickness of 5 nm, irradiation with laser light was performed as in Example 2. Heat treatment was performed at a temperature of 120 ° C.

(Example 2-1)
In the configuration of Example 2, the thickness of the diffusion layer 37b in the electron transport layer 37 was 7 nm.

(Example 2-2)
In the configuration of Example 2, the thickness of the diffusion layer 37b in the electron transport layer 37 was 10 nm.

(Example 2-3)
In the configuration of Example 2, the thickness of the diffusion layer 37b in the electron transport layer 37 was set to 30 nm.

(Example 2-4)
In the configuration of Example 2, the thickness of the diffusion layer 37b in the electron transport layer 37 was 50 nm.

(Example 2-5)
In the configuration of Example 2, the thickness of the diffusion layer 37b in the electron transport layer 37 was set to 60 nm.

(Example 2-6)
In the configuration of Example 2, the thickness of the diffusion layer 37b in the electron transport layer 37 was set to 70 nm.

Next, in the organic EL device of Example 2, the current efficiency due to the difference in thickness of the diffusion layer 37b and LT80 were compared. FIG. 10 is a diagram showing the results of Example 2. In FIG. 10, the voltage indicates the ratio of the voltage of Example 2 when the voltage in the organic EL device of Comparative Example 1 is 1. The current efficiency indicates the ratio of the current efficiency of Example 2 when the current efficiency (cd / A) in Comparative Example 1 is 1. LT80 indicates the ratio of LT80 of Example 2 when LT80 in Comparative Example 1 is set to 1. Here, LT80 is a time (hour) until the light emission luminance reaches 80% when the organic EL device is driven at 400 mA / cm ² and the light emission luminance at the initial point is set to 100%.

  As shown in FIG. 10, in Example 2-1, Example 2-2, and Example 2-3, the voltage is lower than that of Comparative Example 1, and the current efficiency and LT80 are higher. Next, in Example 2-4 and Example 2-5, the voltage is slightly higher than in Comparative Example 1, and the current efficiency and LT80 are higher. Therefore, in Example 2-1 to Example 2-5, the light emission luminance and the light emission lifetime are improved as compared with Comparative Example 1.

  On the other hand, in Example 2-6, the voltage is higher than that of Comparative Example 1. And although LT80 becomes higher than the comparative example 1, it is low compared with Example 2-1 to Example 2-5. In addition, the current efficiency is reduced, and thus the emission luminance is lower than that in Comparative Example 1 in Example 2-6.

  From these results, it is considered that if the thickness of the diffusion layer 37b in the electron transport layer 37 is in the range of 7 nm to 60 nm, the light emission luminance and the light emission lifetime of the organic EL device are improved. When heat treatment is performed, diffusion at the cathode portion occurs due to the heat, and when the electron transport layer 37 does not have a two-layer structure including the diffusion layer 37b, an alkali metal such as Li or an alkali contained in the electron injection layer 38 is used. The earth metal diffuses beyond the electron transport layer 37 to the light emitting layer interface. This is considered to cause a decrease in the light emission efficiency and light emission lifetime of the organic EL device. In contrast, when the electron transport layer 37 has a two-layer structure including the diffusion layer 37b and the thickness of the diffusion layer 37b is set in a range in which the initial characteristics are not deteriorated, Li or the like can diffuse to the light emitting layer interface. Therefore, it is considered that the light emission luminance and the light emission lifetime of the organic EL device are improved.

  Next, in the configuration in which the thickness of the diffusion layer of Example 2 is different, the light emission lifetimes when the temperature of the heat treatment is varied were compared. FIG. 11 is a graph showing the relationship between the heating temperature, the thickness of the diffusion layer, and the light emission lifetime in Example 2. Here, using the organic EL devices having the configurations of Comparative Example 1 (Example 1) and Example 2, heat treatment was performed at temperatures of 95 ° C., 105 ° C., 120 ° C., and 135 ° C. by laser light irradiation. . In FIG. 10, the horizontal axis represents the thickness (nm) of the diffusion layer 37b in the electron transport layer 37, and the vertical axis represents LT80 when LT80 (hour) of Comparative Example 1 subjected to heat treatment at 120 ° C. is 1. Ratio. The polygonal line in FIG. 11 is a plot of LT80 (ratio) when the heating temperature is the same for each of the thicknesses of the diffusion layers in the organic EL devices of Example 1 and Example 2.

  As shown in FIG. 11, LT80 has the longest heat treatment temperature of 120 ° C., the shorter the order of 105 ° C. and 95 ° C., and 135 ° C., regardless of the thickness of the diffusion layer 37 b in the electron transport layer 37. When is the shortest. Also from this result, if the intermediate layer 34 and the diffusion layer 37b are included, the light emission lifetime can be obtained by performing heat treatment at a temperature higher than the lowest temperature among the glass transition temperatures of the materials constituting the organic functional layer 30. Can be seen to improve. Therefore, it is considered that by performing such heat treatment, it is possible to provide an organic EL device in which the light emission lifetime and the light emission efficiency of the organic EL element are improved as compared with the related art.

  Further, from this result, the light emission lifetime is improved as the heat treatment temperature is increased from 95 ° C. to at least 120 ° C., but the light emission lifetime is decreased when the heat treatment temperature is increased to 135 ° C. Therefore, it is considered that the heat treatment temperature is preferably about 120 ° C. When the heat treatment temperature is increased to 135 ° C., it is assumed that the characteristics of the organic functional layer 30 are deteriorated.

  Next, in FIG. 11, when the heat treatment temperatures are the same and the emission lifetimes when the thicknesses of the diffusion layers 37b in the electron transport layer 37 are different are compared, the diffusion layers 37b are obtained when the heat treatment temperatures are 105 ° C. and 120 ° C. The emission lifetime is improved when the thickness is 7 nm to 60 nm, compared with the case where the thickness of the film is 5 nm. In addition, when the heat treatment temperature is 95 ° C. and 135 ° C., the light emission lifetime is improved when the thickness of the diffusion layer 37b is 10 nm to 60 nm, compared with the case where the thickness of the diffusion layer 37b is 5 nm. Therefore, from the results shown in FIGS. 10 and 11, it is considered that the thickness of the diffusion layer 37b is preferably 7 nm to 60 nm.

(Example 3)
<3. Relationship between the thickness of the intermediate layer and the emission lifetime and emission efficiency>
Next, as Example 3, an organic EL device was manufactured by changing the thickness of the intermediate layer 34. In the organic EL device of Example 3, the thickness of the intermediate layer 34 is different from that of the organic EL device of Example 2, and the diffusion layer 37b in the electron transport layer 37 is made of ET4 as a material of 30 nm and 60 nm. , And 70 nm in thickness, but the other configurations are the same. In Example 3, similarly to Comparative Example 1 and Example 2, heat treatment was performed at a temperature of 120 ° C. by laser light irradiation.

(Example 3-1)
The thickness of the intermediate layer 34 was 3 nm, and the thickness of the diffusion layer 37b was 30 nm.

(Example 3-2)
The thickness of the intermediate layer 34 was 10 nm, and the rest of the configuration was the same as in Example 3-1.

(Example 3-3)
The thickness of the intermediate layer 34 was 15 nm, and the rest of the configuration was the same as in Example 3-1.

(Example 3-4)
The thickness of the intermediate layer 34 was 20 nm, and the other configuration was the same as that of Example 3-1.

(Example 3-5)
The thickness of the intermediate layer 34 was 25 nm, and the other configuration was the same as that of Example 3-1.

(Example 3-6)
The thickness of the intermediate layer 34 was 30 nm, and the other configuration was the same as that of Example 3-1.

(Example 3-7)
The thickness of the intermediate layer 34 was 15 nm, and the thickness of the diffusion layer 37b was 60 nm. The other configuration was the same as that of Example 3-1.

(Example 3-8)
The thickness of the intermediate layer 34 was 15 nm, and the thickness of the diffusion layer 37b was 70 nm. The other configuration was the same as that of Example 3-1.

  Further, as Comparative Example 2, the following organic EL device was manufactured.

(Comparative Example 2-1)
The intermediate layer 34 is not provided, and the thickness of the diffusion layer 37b is 5 nm. The other configuration was the same as that of Example 3-1.

(Comparative Example 2-2)
The intermediate layer 34 is not provided, and the thickness of the diffusion layer 37b is 30 nm. The other configuration was the same as that of Example 3-1.

(Comparative Example 2-3)
The thickness of the intermediate layer 34 was 1 nm, and the thickness of the diffusion layer 37b was 30 nm. The other configuration was the same as that of Example 3-1.

  Next, in the organic EL device of Example 3, the current efficiency due to the difference in the thickness of the intermediate layer 34 and LT80 were compared. FIG. 12 is a diagram showing the results of Example 3. In FIG. 12, the voltage indicates the ratio of the voltage of Example 3 when the voltage in the organic EL device of Comparative Example 2-1 is 1. The current efficiency indicates the ratio of the current efficiency of Example 3 when the current efficiency (cd / A) in Comparative Example 2-1 is 1. LT80 indicates the ratio of LT80 of Example 3 when LT80 in Comparative Example 2-1 is set to 1.

  As shown in FIG. 12, in Example 3-1, Example 3-2, Example 3-3, and Example 3-4, the voltage is lower than that of Comparative Example 2-1, and current efficiency and LT80 are reduced. Is getting higher. In Example 3-7, the voltage is higher than that of Comparative Example 2-1, but the current efficiency and LT80 are higher. Therefore, in the organic EL devices of these examples, the light emission luminance and the light emission lifetime are improved as compared with the organic EL device of Comparative Example 2-1.

  However, in Example 3-5, LT80 is the same as that of Comparative Example 2-1, but the voltage is higher and the current efficiency is lower. Moreover, in Example 3-6 and Example 3-8, the voltage is higher than that of Comparative Example 2-1, and the current efficiency and LT80 are reduced.

  From these results, the current efficiency and the light emission lifetime are improved when the thickness of the intermediate layer 34 is 3 nm to 20 nm. However, if the thickness of the diffusion layer 37b in the electron transport layer 37 is 70 nm even if the thickness of the intermediate layer 34 is 15 nm, both the current efficiency and the light emission lifetime are lowered.

  In Comparative Example 2-2, the voltage is higher than that of Comparative Example 2-1, and the current efficiency and LT80 are reduced. In Comparative Example 2-3, the voltage is higher and the current efficiency is lower than that of Comparative Example 2-1. Therefore, when the intermediate layer 34 is not provided or when the intermediate layer 34 is thin, it is considered that the current efficiency and the light emission lifetime are not improved even if the diffusion layer 37b is formed with a preferable thickness.

  Therefore, from the result shown in FIG. 12, it is considered that the thickness of the intermediate layer 34 is preferably 3 nm to 20 nm. From the results shown in FIG. 12, it is considered that the upper limit of the thickness of the diffusion layer 37b in the electron transport layer 37 is preferably 60 nm.

  DESCRIPTION OF SYMBOLS 1 ... Organic EL apparatus, 8 ... Organic EL element, 20 ... Element board | substrate as a board | substrate, 24 ... Anode, 26 ... Cathode, 30 ... Organic functional layer, 33 ... Red light emitting layer as 1st light emitting layer, 34 ... Middle 35, a blue light-emitting layer as a second light-emitting layer, 36, a green light-emitting layer as a third light-emitting layer, 37, an electron transport layer, 37b, a diffusion layer, 500, a mobile phone as an electronic device.

Claims (4)

A substrate, and an organic EL element that is provided on the substrate and in which an anode, an organic functional layer, and a cathode are sequentially stacked,
The organic functional layer is disposed in order on the anode,
A hole transport layer;
A first light emitting layer that emits light in a first color;
An intermediate layer that regulates the flow of electrons and holes;
A second light emitting layer that emits light in a second color different from the first color;
A third light emitting layer that emits light in a third color different from the first color and the second color;
An electron transport layer including a diffusion layer in which alkali metal or alkaline earth metal is diffused, and at least
The organic EL device, wherein the organic EL device is heat-treated at a temperature higher than the lowest temperature among the glass transition temperatures of the respective materials constituting the organic functional layer. Forming an organic EL element by sequentially stacking an anode, an organic functional layer, and a cathode on a substrate;
Heating the organic EL element, and
The step of forming the organic EL element includes the organic functional layer,
A hole transport layer;
A first light emitting layer that emits light in a first color;
An intermediate layer that regulates the flow of electrons and holes;
A second light emitting layer that emits light in a second color different from the first color;
A third light emitting layer that emits light in a third color different from the first color and the second color;
Including at least a step of forming an electron transport layer including a diffusion layer in which an alkali metal or an alkaline earth metal is diffused,
In the step of heat-treating the organic EL element, the organic EL device is produced by heat-treating at a temperature higher than the lowest temperature among the glass transition temperatures of the respective materials constituting the organic functional layer. It is a manufacturing method of the organic EL device according to claim 2,
In the step of heat-treating the organic EL element, the heat treatment is performed by irradiating the organic EL element with laser light.   An electronic device comprising the organic EL device according to claim 1 or the organic EL device manufactured using the method for manufacturing an organic EL device according to claim 2.

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