JP2005322436A - Manufacturing method, device of organic el element, and organic el element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance adhesiveness of a light emitting layer and an electron injecting electrode formed on the light emitting layer, and improve an element characteristic. <P>SOLUTION: While the light emitting layer 4 is heat-treated in a chamber 11 or after it is heat-treated, the electron injection electrode 5 is formed on a surface of the light emitting layer 4 by a vapor deposition method. Because the heat-treatment of the light emitting layer 4 and formation of the electron injection electrode 5 are carried out inside the same chamber 11, adhesion of an impure material onto the surface of the light emitting layer 4 can be reduced, and adhesiveness of the light emitting layer 4 and the electron injection electrode 5 can be enhanced. Furthermore, to improve an element characteristic becomes possible. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention provides, for example, a manufacturing method and apparatus for manufacturing an organic EL element used in an organic EL display device or the like, in which an organic EL (Electroluminescence) film and an electrode film are sequentially laminated on an element substrate, and such manufacturing. The present invention relates to the technical field of organic EL devices manufactured by the method.

In this type of organic EL device manufacturing method, a light-emitting layer, which is an organic thin film made of at least one organic compound, is formed on an electrode film formed on a substrate, and another electrode film is formed thereon. Be filmed.

  Regardless of the type of organic compound constituting the organic thin film, one of the factors affecting the characteristics of the organic EL element is the adhesion between the laminated films. The adhesion between the films affects the contact between the organic thin film and the electrode, and a correlation with the deterioration of the organic EL element is observed. In order to improve the light emission characteristics and lifetime of the organic EL element, the technique for forming an organic thin film is an important issue, and various studies have been made.

  For example, according to the method for manufacturing an organic EL element disclosed in Patent Document 1, after forming an organic layer made of a low molecular weight dye using a vacuum vapor deposition method, it is the lowest among the materials constituting this organic layer. It is said that the lifetime of the organic EL element can be extended by performing a heat treatment in the temperature range of −20 ° C. to + 20 ° C. from the glass transition temperature.

  In addition, according to the method for manufacturing an organic EL element disclosed in Patent Document 2, an ink composition for an organic EL element containing a precursor of a conjugated polymer organic compound is ejected and patterned by an ink jet method, and is subjected to heat treatment. The light emitting layer is formed by polymerizing.

  Furthermore, according to the technique disclosed in Patent Document 3, an organic EL element ink composition comprising an organic light emitting material and a predetermined solvent on a substrate or a hole injection / transport layer formed on the substrate. The heat treatment is performed in a vacuum.

Japanese Patent Laid-Open No. 11-40352 Japanese Patent Laid-Open No. 11-40358 JP 2003-282248 A

  However, an organic thin film produced by a coating method such as an ink jet method has a problem that it adversely affects the characteristics of the organic EL element because the adhesion at the interface between the laminated films is not high. Further, since the heat treatment of the light emitting layer and the electrode formation are separate processes, it is difficult to simplify the manufacturing process.

  Further, when the organic thin film formed by the coating method is heat-treated in the air and then formed thereon by a vapor deposition method, foreign matters such as water and oxygen adhere to the surface of the heat-treated organic thin film, There is a problem that the adhesive force between the organic thin film and the film deposited thereon is lowered. Such a decrease in adhesion between films leads to a decrease in device characteristics such as a decrease in current injection efficiency.

  Therefore, the present invention makes it possible, for example, to improve the adhesion between the organic layer and the electrode laminated thereon and to reduce the manufacturing cost by simplifying the manufacturing process of the organic EL element. An object is to provide an element manufacturing method and apparatus, and an organic EL element.

  In order to solve the above problems, the method for producing an organic EL device according to the present invention includes a step of forming an organic layer by a coating method, and the chamber is heated or after the chamber is heated. And forming an electrode on the organic layer by vacuum deposition.

  According to the method for manufacturing an organic EL element according to the present invention, for example, an organic layer is formed by a coating method such as a spin coating method or an ink jet method on an object on which an electrode is formed on a substrate. Is done. As the organic layer, a high molecular film is suitably formed depending on the coating method, but a low molecular system may be formed. Moreover, an organic layer becomes a light emitting layer in an organic EL element, for example. Subsequently, an electrode is formed on the organic layer by vacuum vapor deposition while heating the organic layer in the chamber or after the heat treatment. As the electrode, a conductive metal film is suitably formed. The electrode is, for example, an electrode for electron injection in the organic EL element. The solvent contained in the organic layer is vaporized by the heat treatment, so that the organic layer is stabilized, and an electrode is formed on the stable organic film simultaneously with or before or after the heat treatment. .

  Here, in particular, in the chamber, the surface of the heat-treated organic layer is not exposed to the outside air, so impurities that adhere to the surface of the organic layer when heat-treated in the atmosphere are present in the present invention. It hardly adheres to the surface of the organic layer. For example, moisture, oxygen, etc. present in the atmosphere hardly adhere to the surface of the heat-treated organic layer. Accordingly, it is possible to deposit an electrode on the clean surface of the organic layer, and it is possible to improve the adhesion between the organic layer and the electrode and improve the element characteristics. In addition, if an electrode is formed directly on the organic layer after heat treatment in the chamber, the organic layer is heat-treated outside the chamber, and then the laminate including the organic layer is moved into the chamber to form an electrode. Compared with the case of forming, for example, the manufacturing process can be simplified to the extent that there is no need for the conveying process or the like, leading to a reduction in manufacturing cost.

  In one aspect of the method for producing an organic EL element according to the present invention, as a pre-process for forming the electrode, the organic layer is heat-treated in a state where the inside of the chamber is reduced to less than atmospheric pressure.

  According to this aspect, in the decompressed chamber, the solvent contained in the organic layer is vaporized at a temperature lower than that under atmospheric pressure, and vaporizes in a short time. Therefore, the heat treatment for stabilizing the organic layer is shorter than the heat treatment under atmospheric pressure, and the time required for manufacturing the organic EL element is shortened. Will improve. Of course, the pressure in the chamber may be sufficiently reduced until a vacuum is reached. Note that the heat treatment may be performed at atmospheric pressure or normal pressure without reducing the pressure.

  In order to solve the above problems, an organic EL device manufacturing apparatus according to the present invention includes a heating unit that heat-treats an organic layer formed by a coating method, and a vapor deposition unit that forms an electrode on the organic layer by a vacuum deposition method. And a first chamber in which the heating means and the vapor deposition means are disposed.

  According to the apparatus for manufacturing an organic EL element according to the present invention, first, an object on which an organic layer is formed by a coating method is prepared. Next, such an object to be formed is accommodated inside the first chamber, for example, by a transfer device or manually. Subsequently, the organic layer is heat-treated in the first chamber by the heating means provided in the first chamber. Thereby, the organic layer is stabilized by evaporating the solvent contained in the organic layer. Further, simultaneously with or before or after this heat treatment, an electrode is formed on the organic film by the vapor deposition means similarly disposed in the first chamber.

  Therefore, as in the case of the manufacturing method according to the present invention described above, impurities that adhere to the surface of the organic layer when heat-treated in the atmosphere hardly adhere to the surface of the organic layer according to the present invention. . Thereby, the adhesive force between the organic layer and the electrode is enhanced, and the element characteristics are improved. In addition, since heat treatment and vacuum deposition can be performed in the same chamber, the manufacturing process can be simplified and the manufacturing cost can be reduced.

  In one aspect of the organic EL device manufacturing apparatus according to the present invention, the heating means and the vapor deposition means are used to form the electrode while the organic layer is heat-treated by the heating means or after the heat treatment. Control means for controlling the vapor deposition means is further provided.

  According to this aspect, the organic layer is heat-treated by the heating means in the first chamber under the control of the control means, and further, the electrode is formed on the organic film by the vapor deposition means simultaneously with or before or after the heat treatment. Is formed. Therefore, a high quality organic EL element can be manufactured efficiently.

  In another aspect of the apparatus for manufacturing an organic EL element according to the present invention, a coating unit for forming the organic layer is provided.

  According to this aspect, the coating unit forms the organic layer on the substrate by a coating method such as an ink jet method or a spin coating method. And the to-be-formed object in which the organic layer was formed in this way can also be moved in a 1st chamber by a conveying apparatus etc., for example. Thus, a manufacturing process can be simplified by performing a series of manufacturing processes from coating formation of an organic layer to heat treatment and electrode formation with one apparatus.

  In the aspect provided with this application means, you may further provide the 2nd chamber by which the said application means is arrange | positioned inside.

  If comprised in this way, since the apply | coating method can be performed in the sealed space in a 2nd chamber, it can suppress effectively that an impurity mixes in the organic layer apply | coated. Therefore, a higher quality organic layer can be manufactured, and finally a higher quality organic EL element can be manufactured.

  Further, when the second chamber apparatus is provided in this way, the object to be formed on which the organic layer is formed is conveyed from the second chamber into the first chamber without breaking the sealed atmosphere. Means may further be provided.

  If comprised in this way, the to-be-formed in which the organic layer was formed, without breaking the sealed atmosphere from the 1st chamber to the 2nd chamber by the conveyance means which has a mechanical or electrical conveyance mechanism, for example Since an object is conveyed, it can suppress effectively that an impurity adheres to the surface of an organic layer during conveyance. Furthermore, by transferring between the two chambers by the transfer means, the time for moving the substrate between the processes can be shortened, and the manufacturing time of the organic EL element can be shortened, thereby reducing the manufacturing cost. Leads to.

  In order to solve the above problems, an organic EL device according to the present invention is formed by vacuum deposition in an organic layer formed by a coating method and in the chamber while heat-treating or heat-treating the organic layer in the chamber. And an electrode formed on the organic layer by a method.

  According to the organic EL device of the present invention, since the adhesion between the organic layer and the electrode is enhanced, an organic EL device with enhanced device characteristics can be obtained. The organic layer may be a light emitting layer, for example. If comprised in this way, it becomes possible to improve the adhesiveness of a light emitting layer and an electrode, and can obtain the organic EL element with which element characteristics, such as current injection efficiency, were improved.

  Further, the electrode may be an electron injection electrode. If comprised in this way, the organic EL element with which the electron injection efficiency from an electrode was raised can be obtained.

  Such an operation and other advantages of the present invention will become apparent from the embodiments described below.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Configuration of organic EL element)
In FIG. 1, an embodiment of the organic EL element according to the present invention will be described. The organic EL element 6 includes a hole injection electrode 2, a hole injection / transport layer 3, a light emitting layer 4, and an electron injection electrode 5 that are sequentially stacked on the substrate 1. The organic EL element 6 is a light emitting element that emits light by recombination of holes injected from the hole injection electrode 2 and electrons injected from the electron injection electrode 5.

  The substrate 1 is a light-transmitting substrate that constitutes an example of the “form” according to the present invention, and for example, a glass substrate is used. Further, wiring for driving the organic EL element may be formed on the substrate 1. The hole injection electrode 2 is a transparent electrode made of, for example, ITO (Indium Tin Oxide). The hole injection / transport layer 3 is a buffer layer provided between the light emitting layer 4 and the hole injection electrode 2, and enhances the bonding property between the light emitting layer 4 and the hole injection electrode 2. The hole injection / transport layer 3 has a function of increasing the hole injection efficiency and increasing the moving speed of the injected holes. The hole injection / transport layer 3 is an organic layer formed by coating an organic compound, and is formed by a coating method such as an inkjet method. As an organic compound that forms the hole injection / transport layer 3, for example, a mixture of a polythiophene derivative such as polyethylenedioxythiophene and polystyrene sulfonic acid can be used.

  The light-emitting layer 4 is a layer in which light is generated by recombination of electrons and holes, and is an organic layer formed by applying an organic compound as a light-emitting material on the hole injection / transport layer 3. . When the light emitting layer 4 is formed, a solution in which an organic compound as a light emitting material is dissolved or dispersed is applied by a coating method such as an inkjet method or a spin coating method. The solvent contained in this solution is vaporized by the heat treatment, and the light emitting layer 4 is formed.

  Further, the organic compound used as the light emitting material may be a material that is polymerized when subjected to heat treatment. As such a polymer material, for example, a precursor of a conjugated polymer organic compound, which is formed on a hole injection / transport layer as a composition for an organic EL device together with a fluorescent dye, and then cured by heating. In this way, it is possible to produce a conjugated polymer. As such a polymer material, for example, when the precursor is a sulfonium salt, a material that becomes a conjugated polymer organic compound by releasing a sulfonium group by heat treatment can be mentioned. Such a conjugated polymer organic compound is solid and has strong fluorescence, and can form a homogeneous solid ultrathin film. Furthermore, since the precursor of such a compound forms a strong conjugated polymer film after curing, the precursor solution (emulsion) is adjusted to a desired viscosity applicable to inkjet patterning before heat curing. It is possible to form a film under optimum conditions in a simple and short time.

  As such a precursor, for example, a polyarylene vinylene precursor is preferable. Since the polyarylene vinylene precursor is water-soluble or soluble in an organic solvent and can be polymerized, a high-quality thin film can be obtained optically. Such polyarylene vinylene precursors include PPV (poly (para-phenylene vinylene)) precursor, MO-PPV (poly (2,5-dimethoxy-1,4-phenylene vinylene)) precursor, CN-PPV (Poly (2,5-bishexyloxy-1,4-phenylene- (1-cyanovinylene))) precursor, MEH-PPV (poly [2-methoxy-5- (2′-ethylenehexyloxy)]-para -Phenylene vinylene) precursor, PPV derivative precursor, PTV (poly (2,5-thienylene vinylene)) precursor poly (alkylthiophene) precursor, PFV (poly (2,5-furylene) Vinylene)) precursor, poly (paraphenylene) precursor, polyalkylfluorene precursor, and the like.

  The precursor of the PPV or PPV derivative is soluble in water and is polymerized by heating after film formation to form a PPV layer. In addition, PPV or PPV derivative precursors have strong fluorescence, and are also conductive polymers in which double-bonded π-electrons are delocalized on the polymer chain, resulting in high-performance organic EL devices. be able to.

  The organic compound forming the light emitting layer 4 may not have the above-described precursor. When forming the light emitting layer 4, you may apply | coat the solution formed by melt | dissolving the light emitting material which is an organic compound in the high boiling point solvent whose boiling point is 200 degreeC or more. Such organic compounds include polyfluorene derivatives, polyphenylene derivatives, polyvinylcarbazole, polythiophene derivatives, or polymer materials such as berylene dyes, coumarin dyes, rhodamine dyes such as rubrene, perylene, 9,10-diphenylanthracene, It is used by doping with tetraphenylbutadiene, Nile red, coumarin 6, quinacridone and the like. These organic compounds are desirably contained at a concentration of 0.5 to 1.5 wt%. The light emitting layer 4 can be formed using any organic compound of high molecular weight material or low molecular weight material. Here, the high molecular weight material is an organic substance having a molecular weight of 10,000 or more, and the low molecular weight material is an organic substance having a molecular weight of about several tens to several hundreds.

  Moreover, as said high boiling point solvent, the thing whose boiling point is 200-400 degreeC under atmospheric pressure can be used, for example, and a high boiling point solvent is used individually or as a mixture. Specific examples of high-boiling solvents include dodecylbenzene (boiling point 331 ° C), cyclohexylbenzene (boiling point 240 ° C), 1,2,3,4-tetramethylbenzene (boiling point 203 ° C), 3-isopropylbiphenyl (boiling point 290 ° C). ), 3-methylbiphenyl (boiling point 272 ° C), 4-methylbiphenyl (boiling point 267 ° C), p-anisyl alcohol (boiling point 259 ° C), 1-methylnaphthalene (boiling point 240-243 ° C), 1, 2, 3 , 4-tetrahydronaphthalene (boiling point 207 ° C.), or derivatives thereof. When an organic compound dissolved in such a high boiling point solvent is discharged by an ink jet apparatus or the like, the solvent is not completely evaporated but remains in the light emitting layer 4. Here, the boiling point (200 to 400 ° C.) of the high boiling point solvent can be lowered by reducing the pressure in the chamber in which the electron injection electrode 5 is deposited to less than atmospheric pressure. Therefore, the light emitting layer 4 can be heat-treated at a temperature lower than the boiling point under atmospheric pressure. By evaporating the solvent contained in the light emitting layer 4 at a low temperature, unevenness and holes generated in the light emitting layer 4 due to bumping are reduced, and the light emitting layer 4 is stabilized. Therefore, it is possible to obtain the light emitting layer 4 having excellent surface smoothness and adhesion between films.

  The electron injection electrode 5 is formed on the light emitting layer 4 by vapor deposition. The electron injection electrode 5 is formed while heat-treating the light-emitting layer 4 in the chamber where the electron injection electrode 5 is deposited or after heat treatment. That is, a series of steps from the heat treatment of the light emitting layer 4 to the electron injection electrode 5 are performed in the same chamber. Therefore, the surface of the heat-treated light emitting layer 4 is not exposed to the atmosphere outside the chamber, and impurities such as moisture and oxygen existing in the atmosphere hardly adhere to the surface of the light emitting layer 4. The surface of the light emitting layer 4 thus heat-treated is a clean surface to which almost no impurities are attached. By depositing the electron injection electrode 5 on the clean surface of the light emitting layer 4, the light emitting layer 4 and the electron Adhesion with the injection electrode 5 is enhanced, and device characteristics such as electron injection efficiency are improved.

  In the present embodiment, the organic EL element in which the hole injection electrode, the hole injection / transport layer, the light emitting layer, and the electron injection electrode are sequentially stacked on the substrate has been described. The organic EL element is not limited to the element structure described above, and any element structure may be used as long as it is an organic EL element obtained by forming an electrode by an evaporation method on an organic layer formed by a coating method. Of course it is good. In addition, in the present embodiment, the case where a simple organic EL element 6 is formed on the substrate 1 is described for convenience, but actually, for example, such an organic EL element is divided into banks and matrixed. A large number of organic EL elements capable of matrix driving for performing full-color image display may be formed on the substrate. Furthermore, a switching element for active matrix driving of such an organic EL element and a wiring therefor may be provided on the substrate 1.

(Manufacturing method of organic EL element)
Next, a method for manufacturing the organic EL element 6 described with reference to FIG. 1 will be described with reference to FIGS. Here, FIG. 2 and FIG. 3 are process diagrams sequentially showing the configuration of the cross section corresponding to FIG. 1 in each process of the manufacturing process.

  First, as shown in FIG. 2A, after the substrate 1 is washed, the hole injection electrode 2 is formed on the substrate 1. Since dust or moisture in the air remains on the surface of the hole injection electrode 2, these are removed by washing. The surface of the hole injection electrode 2 is washed with wet and finally dry washed. Dry cleaning means applying UV (ultraviolet) ozone or processing with oxygen plasma. Further thereon, a composition for forming the hole injection / transport layer 3 is discharged using an ink jet apparatus, and the hole injection / transport layer 3 is formed by heating and drying.

  Subsequently, as shown in FIG. 2B, a light emitting layer 41 is formed on the hole injection / transport layer 3 by applying a light emitting material by a coating method such as an inkjet method or a spin coating method. The light emitting material forming the light emitting layer 41 is an organic compound, and is applied by being dissolved or dispersed in a required solvent. Since the light emitting layer 41 has not been heat-treated yet, the solvent is not sufficiently vaporized. Therefore, the light emitting layer 41 before the heat treatment is an unstable organic layer containing a solvent.

  Subsequently, as shown in FIG. 3A, the laminate formed up to the light emitting layer 41 is moved into the chamber 11 together with the substrate 1, and the pressure in the chamber 11 is reduced to less than atmospheric pressure by a decompression device (not shown). The light emitting layer 41 is heat-treated. The heater 10 is an example of the “heating means” according to the present invention that heats the light emitting layer 41, and heats the light emitting layer 41 through the chucked substrate 1. By reducing the pressure inside the chamber 11 to less than the atmospheric pressure outside the chamber 11, the boiling point of the solvent contained in the light emitting layer 41 is lowered. Therefore, the solvent can be vaporized at a lower temperature than when heat treatment is performed under atmospheric pressure, and the solvent contained in the light emitting layer 41 can be quickly removed at a lower temperature.

  The temperature control of the heater 10 is performed by the control unit 13 as an example of the “control unit” according to the present invention. The control unit 13 also controls the vapor deposition unit 12 as well as the temperature control of the heater 10. The control unit 13 controls the deposition conditions such as the temperature of the heater 10 and the temperature of the deposition unit 12 to form the electron injection electrode 5 under optimum deposition conditions.

  According to the method for manufacturing an organic EL device according to this embodiment, the boiling point of the solvent can be lowered by reducing the pressure in the chamber 11 to a vacuum state, and a low temperature range such as room temperature (20 ° C.) to 150 ° C. The light emitting layer 41 can also be heat-treated. Since the heat treatment of the light emitting layer 41 is completed in a shorter time than when heat treatment is performed under atmospheric pressure, the manufacturing time of the organic EL element can be greatly shortened, and the manufacturing process of the organic EL element is simplified. It becomes possible to do. Further, the temperature at which the light emitting layer 41 is heat-treated is preferably equal to or lower than the boiling point of the solvent contained in the light emitting layer 41. By heat-processing below the boiling point of a solvent, it can suppress that a solvent bumps, and can suppress that the surface of the light emitting layer 41 is roughened by bumping of a solvent. Since the light emitting layer 41 formed by the coating method can have a uniform film thickness as compared with the light emitting layer formed by the vapor deposition method, the light emitting layer can be obtained while taking advantage of a uniform film thickness obtained by the coating method. The surface roughness of 41 can be reduced, and the light emitting layer 4 having good film quality can be formed.

  It is more preferable to heat-treat the light emitting layer 41 at −15 ° C. to + 40 ° C. from the glass transition temperature of the organic compound forming the light emitting layer 41 and below the boiling point of the solvent. By heating below the boiling point of the solvent, bumping of the solvent remaining in the light emitting layer 41 can be suppressed and vaporization can be performed slowly. Therefore, the surface of the light emitting layer 4 is not roughened by the heat treatment. More preferably, it is possible to control the film quality such as fluidizing the light emitting layer 41 by heat treatment near the glass transition temperature and smoothing the surface, and the electron injection deposited on the light emitting layer 4. Adhesiveness with the electrode 5 can also be improved.

  The light emitting layer 41 may be polymerized by heat-treating the light emitting layer 41 that has not been sufficiently polymerized when formed by a coating method in the chamber 11 under reduced pressure. As such a light emitting material, a material containing a precursor of a conjugated polymer organic compound and a fluorescent substance that changes the light emission characteristics of the light emitting layer can be exemplified.

  Subsequently, as shown in FIG. 3B, the electron injection electrode 5 is formed on the surface of the heat-treated light emitting layer 4 by vapor deposition. The electron injection electrode 5 is formed by evaporating an electrode material evaporated from the vapor deposition unit 12 disposed in the chamber 11 on the surface of the light emitting layer 4. That is, a series of manufacturing processes from the heat treatment of the light emitting layer 4 to the vapor deposition of the electron injection electrode 5 are performed in the same chamber 11. According to such a method for manufacturing an organic EL element, since the surface of the light emitting layer 4 once heat-treated is not exposed to the atmosphere, impurities such as moisture and oxygen are almost adhered to the surface of the light emitting layer 4. There is no. Therefore, the electron injection electrode 5 can be formed on the clean surface of the light emitting layer 4, the adhesion between the light emitting layer 4 and the electron injection electrode 5 can be increased, and the device characteristics can be improved. Furthermore, compared with the case where the electron injection electrode is deposited after the laminate having the light emitting layer formed is transported into the chamber, for example, the manufacturing process can be simplified because the transport process is not required. It also leads to a reduction in the manufacturing cost of EL elements.

  The light emitting layer 4 may be heat-treated at atmospheric pressure or normal pressure without reducing the pressure inside the chamber 11, or a gas other than air may be introduced into the chamber 11 and heat-treated. By performing the heat treatment in the sealed chamber 11, excess impurities do not adhere to the light emitting layer 4.

  Further, the present invention is not limited to the case where the electron injection electrode 5 is formed after the heat treatment of the light emitting layer 4, and the electron injection electrode 5 may be formed while the light emitting layer 4 is heat treated. Thus, the manufacturing process can be shortened by forming the electron injection electrode 5 while heat-treating the light emitting layer 4. Moreover, the manufacturing method of the organic EL element of this embodiment is not limited to the case where the electron injection electrode 5 is directly formed on the surface of the light emitting layer 4, and the case where the electron transport layer and other layers are deposited on the light emitting layer 4. It is also a suitable method, and the adhesion between these layers can be increased.

  The organic EL element 6 can be manufactured by the above manufacturing process. Further, after the electron injection electrode 5 is formed, the organic EL element is completed by sealing from above the electron injection electrode 5 in the sealing process. .

  In the aspect described in this embodiment, a case where one organic EL element is manufactured is described. However, if the method for manufacturing an organic EL element according to this embodiment is applied, a plurality of elements are formed simultaneously. It is also possible to manufacture organic EL elements that emit light of different wavelengths, that is, light of different colors. For example, if an organic compound for forming a light emitting layer is separately applied by an ink jet method, a plurality of organic EL elements for color display having different emission wavelengths can be formed on one substrate.

(Organic EL device manufacturing equipment)
Next, an embodiment of an organic EL element manufacturing apparatus (hereinafter referred to as an organic EL manufacturing apparatus) according to the present invention will be described with reference to FIG. FIG. 4 is a configuration diagram of the organic EL manufacturing apparatus 20.

  In FIG. 4, the organic EL manufacturing apparatus 20 according to this embodiment includes (I) a heater 27 that heat-treats a light emitting layer that is an organic layer, and a vapor deposition unit 29 that forms an electrode such as an electron injection electrode thereon. A vacuum deposition apparatus 31 including a chamber 32 in which a heater 27 and a deposition unit 29 are disposed, and a coating apparatus 21 including (II) an inkjet apparatus 22 for forming a light emitting layer by a coating method in a chamber 35. And is configured.

  The coating device 21 includes an inkjet device 22 that is an example of a coating unit, and the inkjet device 22 is disposed inside a chamber 35 that is a second chamber. Furthermore, the coating device 21 includes a stage 34 for fixing the stacked body 23a when forming the light emitting layer, and conveyors 24 and 25 for transporting the stacked body 23b including the light emitting layer. Further, the coating device 21 may include a decompression device 37 and a gas introduction device 38 for adjusting the atmospheric pressure and atmosphere in the chamber 35.

  The ink jet device 22 is an example of the “coating means” according to the present invention that discharges ink to form an organic layer such as a light emitting layer on the laminate 23a. The ink constituting the light emitting layer contains an organic compound such as a light emitting material. The laminate 23a is formed by laminating thin films such as a hole injection electrode and a hole injection / transport layer on a substrate. In FIG. 4, the laminate 23a and the laminate 23a and The detailed layer structure of 23b is not shown. Further, the coating means is not limited to the ink jet device 22, and may be a coating device such as a spin coater, and may be another coating device. Of course, the laminated structure of the laminated body 23b is not limited to the laminated structure of the present embodiment.

  The chamber 35 constituting the coating apparatus 21 is an example of the “second chamber” according to the present invention, as opposed to the chamber 32 that is an example of the “first chamber” according to the present invention. The inside of the chamber 35 is maintained in a clean state so that impurities such as oxygen and moisture do not adhere to the light emitting layer after the formation of the coating.

  The coating device 21 may include a decompression device 37 for decompressing the inside of the chamber 35 and a gas introduction device 38 for introducing a predetermined type of gas into the chamber 35. The decompression device 37 decompresses the interior of the chamber 35 and removes impurities such as moisture and oxygen existing inside the chamber 35. The gas introduction device 38 discharges moisture and oxygen to the outside of the chamber 35 by introducing an inert gas or the like into the chamber 35 and maintains the inside of the chamber 35 in a clean state. The decompression device 37 and the gas introduction device 38 are another decompression device and gas introduction device for the decompression device and the gas introduction device provided in the vacuum vapor deposition device 31. In this manner, by applying the light emitting layer in the chamber 35 maintained in a clean state, it is possible to reduce the adhesion of impurities to the light emitting layer, and to improve element characteristics and adhesion.

  The organic EL manufacturing apparatus 20 may include only the vacuum vapor deposition apparatus 31, and the stacked body 23 b on which the light emitting layer is applied is put into the vacuum vapor deposition apparatus 31 from another apparatus disposed away from the vacuum vapor deposition apparatus 31. May be. As will be described later, the organic EL manufacturing apparatus 20 can automatically carry the laminated body 23b from the coating apparatus 21 to the vacuum vapor deposition apparatus 31, and the laminated body 23b can be more efficiently compared to the case where a separate coating apparatus is provided. Can be transported. Therefore, according to the organic EL manufacturing apparatus 20, an organic EL element can be efficiently manufactured.

  The conveyors 24 and 25 are an example of the “conveying means” according to the present invention for conveying the laminate 23b, which is an object to be formed, from the coating apparatus 21 to the vacuum vapor deposition apparatus 31. The laminated body 23b in which the light emitting layer is formed on the laminated body 23a is delivered to the conveyor 24 by the stage 34. The conveyor 24 conveys the laminated body 23b upward, turns the laminated body 23b upside down during or before conveyance, and inverts the upper surface and the lower surface of the laminated body 23b. By reversing the upper surface and the surface of the stacked body 23b, the electron injection electrode can be formed as it is without reversing the stacked body 23b by the vacuum vapor deposition apparatus 31 described later. The conveyor 25 receives the laminated body 23b from the conveyor 24, and conveys the laminated body 23b to the vacuum evaporation apparatus 31. The stacked body 23 b is transported to the vacuum deposition apparatus 31 via the gate valve 26 that connects the coating apparatus 21 and the vacuum deposition apparatus 31. The gate valve 26 has airtightness. By transporting the stacked body 23b via the gate valve 26, a light emitting layer is formed in the chamber 35 that is a sealed space, and then the stacked body 23b is externally attached. It can be transferred to the chamber 32 of the vacuum deposition apparatus 31 without being exposed to the atmosphere. As described above, when the laminate 23b is transported in the sealed space, the impurities hardly adhere to the surface of the light emitting layer formed by coating. Therefore, the laminate 23b can be transported to the vacuum evaporation apparatus 31 in a state where a clean surface is maintained, and the adhesion between the electron injection layer formed on the light emitting layer and the light emitting layer can be increased, Element characteristics can also be improved. In addition, the to-be-formed object by which the light emitting layer was apply | coated and formed may be manually conveyed to the vacuum evaporation system 31, and the heat processing of a light emitting layer and vapor deposition of an electron injection electrode should just be performed in the same chamber.

  The coating device 21 does not need to have a heating means for heat-treating the light emitting layer. The stacked body 23 b is heated in the chamber 32 after being transported to the vacuum deposition apparatus 31. Therefore, it is not necessary to provide heating means for heat-treating the light emitting layer in the coating device 21, and the configuration of the coating device 21 can be simplified.

  The vacuum deposition apparatus 31 includes a heater 27 for heat-treating a light emitting layer formed by a coating method, a vapor deposition means 29 for forming an electron injection electrode on the light emitting layer by a vacuum vapor deposition method, a heater 27 and a vapor deposition unit 29 inside. A chamber 32 is provided.

  The vacuum vapor deposition apparatus 31 holds the laminated body 23 b conveyed from the coating apparatus 21 with the substrate holder 28. The substrate holder 28 can also be used as a mask for patterning the electron injection electrode on the surface of the light emitting layer. The lower side of the substrate holder 28 faces the vapor deposition unit 29, and the electron injection electrode is formed on the surface of the light emitting layer facing the vapor deposition unit 29 from the opening of the substrate holder 28.

  The heater 27 is an example of a heating unit for heating the stacked body 23b on which the light emitting layer is formed. The heater 27 only needs to have an output capable of heat-treating the light-emitting layer in a temperature range corresponding to the characteristics of the solvent contained in the light-emitting layer. For example, the heater 23 is raised from at least 100 ° C. to 200 ° C. What is necessary is just to have the output which can be heated. According to the vacuum evaporation apparatus 31, the inside of the chamber 32 can be depressurized, and the boiling point of the solvent remaining in the light emitting layer can be lowered. Therefore, the output range of the heater 27 heats the light emitting layer under atmospheric pressure. It may be smaller than the case of processing.

  The vapor deposition unit 29 is an example of the “vapor deposition means” according to the present invention. The vapor deposition unit 29 is disposed below the chamber 32 and is located immediately below the stacked body 23 b held by the substrate holder 28. The vapor deposition unit 29 includes, for example, a crucible or boat filled with a vapor deposition material, and a heater for heating the crucible or boat. The electron injection electrode is formed by evaporating the electrode material evaporated from the vapor deposition means 29 on the surface of the light emitting layer.

  The chamber 32 is provided with a decompression device 33. According to the decompression device 33, it is possible to perform heat treatment of the light emitting layer and vapor deposition of the electron injection electrode in a state where the pressure in the chamber is reduced from atmospheric pressure. The chamber 32 may be provided with a gas introduction device 36. According to such a gas introduction device, by introducing an inert gas or the like into the chamber 32, impurities such as moisture and oxygen can be discharged to the outside of the chamber 32, so that a light emitting layer having a clean surface can be formed. An electron injection electrode can be formed. Moreover, the vacuum evaporation apparatus 31 should just be provided with at least one of the decompression device 33 and the gas introducing device 36. FIG. By adjusting the atmosphere and pressure in the chamber 32 at least one of the decompression device 33 and the gas introduction device 36, an organic EL device having excellent device characteristics can be manufactured.

  The heater 27 and the vapor deposition unit 29 are controlled by the control unit 39. When the electron injection electrode is formed on the surface of the light emitting layer of the laminate 23b, the control unit 39 controls the heating temperature of the heater 27 and the vapor deposition unit 29 so that vapor deposition is performed under optimum conditions.

  Furthermore, the vacuum deposition apparatus 31 may include a film thickness monitor. The crystal vibration film thickness monitor 30 is, for example, a film thickness monitor equipped with a crystal resonator, and is provided facing downward so that the crystal resonator faces the vapor deposition source 29. The crystal oscillator thickness monitor 30 is a monitor that calculates the film thickness from the change in weight of the vapor deposition material attached to the crystal oscillator. The crystal oscillator film thickness monitor 30 can accurately control the film forming conditions of the electron injection electrode based on the measured film thickness data.

  As described above, according to the organic EL device manufacturing apparatus of the present invention, the heat treatment of the organic layer such as the light emitting layer and the formation of the electrode on the light emitting layer can be continuously performed in the same chamber. It is possible to reduce the manufacturing cost by simplifying the manufacturing process of the organic EL element.

  Furthermore, according to the organic EL device manufacturing apparatus according to the present invention, since the object on which the light emitting layer is formed is isolated from the outside of the chamber, impurities are once formed on the surface of the light emitting layer that has been heat-treated. The electron injection electrode can be deposited on the clean surface of the light emitting layer with little adhesion. Therefore, adhesion of impurities such as water to the surface of the heat-treated organic layer can prevent a decrease in the adhesive force between the organic layer and the electrode film deposited thereon, thereby improving device characteristics. be able to.

  Note that the present invention is not limited to the above-described embodiment, and can be appropriately changed within a scope not departing from the gist or idea of the invention that can be read from the claims and the entire specification, and an element accompanying such a change. The device manufacturing method and the manufacturing apparatus are also included in the technical scope of the present invention.

It is sectional drawing of the organic EL element which concerns on embodiment of this invention. It is manufacturing process sectional drawing (the 1) which shows the manufacturing method of the organic EL element which concerns on embodiment of this invention later on. It is manufacturing process sectional drawing (the 2) which shows the manufacturing method of the organic EL element which concerns on embodiment of this invention later on. It is a block diagram of the manufacturing apparatus of the organic EL element which concerns on embodiment of this invention.

Explanation of symbols

  Light emitting layer 4, electron injection electrode 5, organic EL element 6, heater 10, chambers 11 and 32, vapor deposition units 12 and 29, control units 13 and 39, ink jet device 22, organic EL manufacturing device 20, coating device 21, vacuum vapor deposition Device 31, decompression device 33, 37, gas introduction device 36, 38

Claims (8)

Forming an organic layer by a coating method;
Forming an electrode on the organic layer by vacuum vapor deposition in the chamber while heat-treating the organic layer in the chamber or after the heat-treatment;
A method for producing an organic EL device, comprising:   2. The method of manufacturing an organic EL element according to claim 1, wherein in the step of forming the electrode, the organic layer is heat-treated in a state where the inside of the chamber is decompressed to less than atmospheric pressure. Heating means for heat-treating the organic layer formed by the coating method;
A vapor deposition means for forming an electrode on the organic layer by vacuum vapor deposition;
A first chamber in which the heating means and the vapor deposition means are disposed;
An apparatus for manufacturing an organic EL element, comprising:   The heating means and a control means for controlling the vapor deposition means are further provided so that the electrode is formed by the vapor deposition means while the organic layer is heated by the heating means or after the heat treatment. The manufacturing apparatus of the organic EL element of Claim 3.   The apparatus for producing an organic EL element according to any one of claims 3 to 4, further comprising a coating unit for forming the organic layer.   The organic EL element manufacturing apparatus according to claim 5, further comprising a second chamber in which the coating unit is disposed.   The apparatus according to claim 6, further comprising a conveying unit configured to convey the object on which the organic layer is formed from the second chamber to the first chamber without breaking a sealed atmosphere. An organic EL device manufacturing apparatus. An organic layer formed by a coating method;
An electrode formed on the organic layer by vacuum deposition in the chamber while heat-treating the organic layer in the chamber or after the heat-treatment,
An organic EL device comprising:

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