JP2006114453A - Organic el element, manufacturing method of the same, and organic el device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic EL element having high brightness and a long life which can be relatively easily applied, a manufacturing method of the same, and an organic EL device provided with the organic EL element. <P>SOLUTION: The EL element is composed of first lamination bodies (20A) laminated on one face of a substrate (10) and second lamination bodies (20B) laminated at a position opposing the first lamination body on the other face of the substrate. The first and the second lamination bodies are constituted of a pair of electrode layers (11a, 21, 24) of which at least one layer is transparent, and an organic layer (23) interposed between the pair of electrode layers. Each of first and second transparent insulation layers (30) is interposed between the first lamination layer and the second lamination body. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention includes, for example, an organic EL element in which an organic EL (Electroluminescence) film and an electrode film are sequentially laminated on a substrate, a manufacturing method thereof, and an illumination light source, a color display, and the like including such an organic EL element. The present invention relates to the technical field of organic EL devices such as printer heads.

  This type of organic EL element has a laminated structure in which an organic thin film including at least a light emitting layer is sandwiched between a pair of electrode films on a substrate, and carriers injected from the pair of electrode films are recombined in the light emitting layer. It emits light. At least one of the pair of electrode films is a transparent electrode such as ITO (Indium Tin Oxide) in order to extract light outside the device.

Although such an organic EL element is expected to be applied to a display or the like, there is a problem that the lifetime becomes extremely short as the luminance increases. For example, when light is emitted at about several thousand cd / m ² required for a display, the element is remarkably deteriorated and it is not yet easy to put it to practical use.

  On the other hand, Patent Document 1 describes a technique for doubling substantial luminance by using an organic EL element having a configuration in which a plurality of light emitting units are stacked between a pair of electrodes. These light emitting units are each partitioned by a layer forming an equipotential surface, and are connected in series. In such an organic EL element, since each light emitting unit emits light simultaneously when a predetermined voltage is applied between both electrodes, it is possible to obtain light emission with high luminance and high efficiency which has been difficult to realize so far.

JP 2003-45676 A

  However, in the above configuration, since the light emitting units are connected in series, the driving voltage increases according to the number of light emitting units, and thus there is a technical problem that a high voltage driving circuit is required. In other words, it is technically difficult to apply the existing drive circuit as it is, and since the drive circuit element for high voltage is expensive, the application of the organic EL element is necessarily limited to a high-grade apparatus. become.

  The present invention has been made in view of the above-mentioned problems, for example, and has a high luminance and a long lifetime, and can be applied relatively easily, a method for manufacturing the same, and such an organic EL element. It is an object to provide an organic EL device provided.

  In order to solve the above problems, the organic EL element of the present invention is laminated on one surface of a substrate, and at least one of the pair of electrode layers is transparent and an organic layer sandwiched between the pair of electrode layers. An n number of first stacked bodies (where n is a natural number of 2 or more), a first transparent insulating layer inserted between each of the n first stacked bodies, and the substrate It is laminated | stacked on the other surface in the position facing the said 1st laminated body, and at least one is comprised including a pair of transparent electrode layer and the organic layer pinched | interposed between this pair of electrode layer ( Provided that m is a natural number of 2 or more) and a second transparent insulating layer inserted between each of the m second stacked bodies.

The organic EL element of the present invention has a structure in which a plurality of laminated bodies that can function as individual light emitting elements are laminated on both one side and the other side of the substrate.
Each laminate is formed by sandwiching a single layer or multiple layers of organic layers between a pair of electrode layers. The organic layer includes a light emitting layer, and may further include, for example, a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, or the like. Light generated in the light emitting layer is extracted from the light emitting side of the stacked body. However, in such an organic EL element, light cannot be extracted outside the element unless it passes through a plurality of stacked bodies. Therefore, at least the electrode layer located on the light emitting side of the element needs to be a transparent electrode such as ITO (Indium Tin Oxide). The light emitting direction of the element is preferably set centering on the direction perpendicular to the layer surface of the laminate so that the element emits light, and the light may be emitted from either the upper surface side or the lower surface side of the substrate. The light may be emitted from both the upper surface side and the lower surface side.

  In such an organic EL element, since a plurality of stacked bodies as light emitting units are stacked, if these stacked bodies are driven at the same time, high light emission can be realized by overlapping these to emit light. In this case, in each stacked body, the current supply amount can be relatively suppressed, so that the lifetime of the element can be extended.

  Moreover, in this organic EL element, since the laminated body is configured to be laminated using both surfaces of the substrate, it is easy to form a laminated structure. For example, when four laminates are laminated on one side of the substrate and two are formed on each side of the substrate, the former is structurally more difficult to manufacture even though the light emission luminance as the element is the same. Is expensive. Actually, as the number of layers to be laminated on one side of the substrate increases, a step due to the presence of lower-layer wiring or the like occurs on the base surface, making it difficult to stack the layers flatly. As a result, the wiring density of the lead-out wiring increases, or the wiring space is expanded and the aperture ratio decreases. Therefore, if the lead-out wiring is integrated in the stacking direction in order to reduce the wiring density, a deep contact hole is now required. In any case, as the stacked body is stacked, the layout of the lead wiring becomes more complicated, and it becomes difficult to manufacture while maintaining the characteristics and reliability of the element. On the other hand, in the present invention, since the laminate is laminated using both sides of the substrate, it is only necessary to form fewer laminates on each side of the substrate than the number of layers to be originally laminated. Double can be secured. Therefore, in the organic EL element of the present invention, it is possible to reduce manufacturing problems caused by the increase in the number of stacked layers as described above.

  Furthermore, in the present invention, the laminates are partitioned by a transparent insulating layer. The insulating layer is transparent for the same reason as the electrode layer. By electrically insulating the stacked bodies, the stacked bodies can be connected in parallel. In principle, all the stacked bodies connected in parallel are driven at the same voltage as the voltage applied to the entire device. Therefore, the organic EL element can be driven by an existing drive circuit without using a high-voltage drive circuit only by devising the wiring. Since the driving circuit for high voltage is quite expensive, the cost of the apparatus is greatly increased. However, when the organic EL element of the present invention is used, such a fear can be avoided and the apparatus can be widely applied to various apparatuses.

  As a result, according to the organic EL element of the present invention, it is possible to increase the luminance and extend the lifetime, and it can be easily applied to various devices.

  In one aspect of the organic EL device of the present invention, the transparent electrode layer and the first and second transparent insulating layers in the first and second laminates are each formed by an ion plating method.

  According to this aspect, the transparent electrode layer is formed by the ion plating method. As described above, in this organic EL element, a transparent electrode such as ITO is used for the electrode layer located on the light emitting side in order to transmit light in the light emitting direction of the element. Such a transparent electrode material is usually formed by sputtering. However, when forming an electrode by sputtering, the organic layer deposited on the lower layer side may be damaged. Therefore, when forming a structure in which a transparent electrode is provided on an organic layer, such as a so-called “top emission type” organic EL element that extracts light from the upper surface side of the substrate or the organic EL element of Patent Document 1 above. In practice, the electrode layer is formed using metal instead of ITO. This is because the metal thin film can be formed by a method such as vapor deposition that does not damage the organic layer. However, in that case, the transmittance is remarkably lowered as compared with the case where a transparent electrode material such as ITO is used.

  On the other hand, in the present invention, since the transparent electrode layer is formed by the ion plating method, the transparent electrode layer can be formed of a transparent electrode material such as ITO without damaging the organic layer. It becomes. In the organic EL device of the present invention, since there are a plurality of such transparent electrode layers, the transmittance is good in all of them, and the effect of having almost no damage to any of the organic layers is great, The brightness of the element can be sufficiently increased.

  In addition, since the transparent insulating layer is also formed by the ion plating method here, it is possible to improve the reliability with respect to the damage prevention of the organic layer, and to form the transparent insulating layer and the transparent electrode layers positioned above and below it. Films can be continuously formed using the same ion plating apparatus, and the film formation throughput can be improved.

  In another aspect of the organic EL element of the present invention, the electrode layer which is the uppermost layer on the one surface in the first stacked body, or the uppermost layer on the other surface in the second stacked body. The electrode layer is made of a metal film, and the electrode layers other than the metal film in the first and second stacked bodies are made of a transparent conductive film.

  According to this aspect, the organic EL element is configured to extract light from one side or the other side of the substrate. That is, the uppermost electrode layer on either one of the both surfaces of the substrate is made of a metal film that reflects light, while the electrode layers positioned on the light emitting side are both made of a transparent conductive film to extract light. .

  In this way, by taking out light from one side in the stacking direction of the first and second stacked bodies stacked via the substrate, it is possible to efficiently increase the luminance.

  In another aspect of the organic EL element of the present invention, each of the first and second stacked bodies includes an electron injection layer for injecting electrons into the organic layer between the pair of electrode layers.

  According to this aspect, the electron injection layer is included in each of the first and second stacked bodies. In the organic EL device of the present invention, the electrode layer located on the light emitting side is a transparent electrode layer, but when the cathode is formed of ITO or the like, electrons are supplied to the organic layer because of its high work function. difficult. Therefore, in order to increase the electron injection efficiency, an electron injection layer is provided between the organic layer and the cathode. Thereby, it is possible to maintain or improve the luminous efficiency of each laminated body.

  In order to solve the above-described problems, an organic EL device of the present invention includes the organic EL element of the present invention (including various aspects thereof) and the pair of electrode layers in each of the first stacked bodies on one end side. The first power supply wiring that is electrically connected to one and the other end is electrically connected to the power source for driving each of the first stacked bodies, and each of the first stacked bodies A first electrode wiring electrically connected to the other of the pair of electrode layers, and one end of the first electrode wiring electrically connected to one of the pair of electrode layers in each of the second stacked bodies, and the other end The side is electrically connected to a second power supply wiring electrically connected to a power source for driving each of the second stacked bodies, and to the other of the pair of electrode layers in each of the second stacked bodies. Second electrode wiring, and for supplying the first power Each of the n first stacked bodies is electrically connected in parallel to the power supply by a line and the first electrode wiring, and the m is connected by the second power supply wiring and the second electrode wiring. Each of the second stacked bodies is configured to be electrically connected in parallel to the power source.

  According to the organic EL device of the present invention, since the above-described organic EL element according to the present invention is provided, high luminance and long life can be achieved. Further, in this apparatus, the organic EL element is electrically parallel to the power source by the power supply wiring and the electrode wiring on the one surface and the other surface of the substrate, respectively. Configured to be connected. The first stacked bodies connected in parallel with each other are driven under the same voltage, and the second stacked bodies connected in parallel with each other are also driven under the same voltage. Therefore, this organic EL device can be driven by an existing power supply circuit without using a high-voltage power supply circuit, and can be widely applied to various devices while suppressing an increase in the cost of the device.

  Such an organic EL device is, for example, a projection display device, a television set, a mobile phone, an electronic notebook, a word processor, a viewfinder capable of performing high-power image display with low power consumption and high brightness. Various types of electronic equipment such as video tape recorders, direct-view type video tape recorders, workstations, videophones, POS terminals, touch panels, etc., printers using organic EL devices as exposure heads, image forming devices such as copy and facsimile realizable.

  In order to solve the above problems, the organic EL device manufacturing method of the present invention is laminated on one surface of a substrate, at least one of which is an organic layer sandwiched between a pair of transparent electrode layers and the pair of electrode layers. N (where n is a natural number greater than or equal to 2) first laminated bodies configured to include layers, and first transparent insulating layers respectively inserted between the n first laminated bodies, It is laminated | stacked in the position facing the said 1st laminated body in the other surface of the said board | substrate, and at least one was comprised including a pair of transparent electrode layer and the organic layer pinched | interposed between this pair of electrode layer An organic EL element including m (where m is a natural number of 2 or more) second stacked bodies and a second transparent insulating layer inserted between each of the m second stacked bodies is manufactured. A method for manufacturing an organic EL device for use in a transparent electrode is at least one of the pair of electrode layers. Forming the first laminate on the one surface, including a conductive layer forming step of forming a transparent electrode layer as a transparent conductive film by an ion plating method, and an organic layer forming step of forming the organic layer, a first stacking step repeated n times, a first insulating layer forming step of forming the first transparent insulating layer on the first stacked body by an ion plating method after the first stacking step, and the pair of pairs A conductive layer forming step of forming a transparent electrode layer, which is at least one of the electrode layers, as a transparent conductive film by an ion plating method, and an organic layer forming step of forming the organic layer. A second insulating layer formed on the other surface and repeated m times; and after the second laminating step, the second transparent insulating layer is formed on the second laminated body by an ion plating method. Layered And a step.

According to the method for manufacturing an organic EL element of the present invention, the electrode layer and the transparent insulating layer in each of the first and second laminates are formed by an ion plating method. A transparent electrode material such as ITO is used for forming the transparent electrode layer, and a transparent insulating material such as SiO ₂ , SiN _x , and AlO ₂ is used for forming the transparent insulating layer. Such a material is usually formed by sputtering or the like. If these transparent materials are formed by sputtering or the like in the production of an organic EL element, the underlying organic layer may be damaged by exposure to plasma.

  On the other hand, in the manufacturing method of the present invention, since the transparent electrode layer and the transparent insulating layer are formed by the ion plating method, the organic layer is hardly damaged, and each of these layers has good permeability. It can be formed of a transparent material. In the organic EL device of the present invention, since there are a plurality of such transparent electrode layers, the transmittance is good in all of them, and the effect of almost no damage to any of the organic layers is great. It is possible to sufficiently increase the luminance of the element. That is, according to the method for manufacturing an organic EL element of the present invention, the above-described organic EL element of the present invention can be manufactured with good characteristics.

  Further, in this case, at least the transparent insulating layer and the transparent electrode layers positioned above and below it can be continuously formed in the same ion plating apparatus, and the film formation throughput can be improved. In order to manufacture the organic EL device of the present invention, it is necessary to form a larger number of layers than usual, and thus improvement in manufacturing efficiency is important.

  In one aspect of the method for producing an organic EL element of the present invention, at least a part of the steps is formed by connecting a vacuum vapor deposition apparatus and an ion plating apparatus through a vacuum transfer chamber so that a sealed space can be formed. The conductive layer forming step and the first and second insulating layer forming steps are executed in the ion plating apparatus.

  According to this aspect, at least a part of the layer formation is performed using a unique film forming apparatus. This film forming apparatus can perform ion plating and vacuum deposition, and the formation of the transparent conductive layer and the transparent insulating layer is performed in this apparatus. Further, for example, a part or all of the organic layer, or a part of an element such as a metal electrode provided when one side of the substrate is a light emitting side is formed by vacuum deposition in this apparatus.

  Here, since the film forming apparatus is hermetically sealed as a whole, the substrate surface is exposed to the atmosphere by taking out the substrate from the apparatus after ion plating or vacuum vapor deposition, and adverse effects such as oxidation or adsorption of impurities are suffered. It is possible to prevent fear.

  In an aspect using this film forming apparatus, when each of the first and second stacked bodies is formed so as to include an electron injection layer for injecting electrons into the organic layer, between the pair of electrode layers, The first and second stacking steps include an electron injection layer forming step of forming the electron injection layer by a vacuum vapor deposition method in the vacuum evaporation apparatus, and after the electron injection layer forming step and before the conductive layer forming step. And a transfer step of transferring the substrate from the vacuum deposition apparatus to the ion plating apparatus through the vacuum transfer chamber.

  In this aspect, when each stacked body manufactures an organic EL element having an electron injection layer, the electron injection layer is formed by vacuum deposition in the film formation apparatus, and then in the same film formation apparatus, A transparent electrode layer is formed on the electron injection layer by ion plating.

  In this series of steps, if the substrate is taken out from the vacuum deposition apparatus into the outside air and placed in the ion plating apparatus, the electron injection layer may be oxidized by being exposed to the outside air. On the other hand, in this mode, the substrate is transferred from the vacuum deposition apparatus in the film forming apparatus to the ion plating apparatus between the processes via the vacuum transfer chamber. At this time, since the substrate is transported between the devices without being exposed to the atmosphere, exposure of the electron injection layer on the substrate surface to the atmosphere may cause adverse effects such as oxidation or adsorption of impurities. It is possible to prevent. Therefore, an element with good characteristics can be manufactured.

  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 with reference to the drawings.

<1: Organic EL device>
First, with reference to FIGS. 1 to 3, a basic configuration of an organic EL element according to an embodiment of the present invention will be described. Each of FIGS. 1 to 3 is a cross-sectional view illustrating a schematic configuration of the organic EL element according to the present embodiment.

<1-1: Top emission type organic EL element>
In FIG. 1, an organic EL element 1 is a top emission type light emitting element that extracts light from the upper surface side of an element substrate 10, and is formed on the upper surface of an element substrate 10 made of a glass substrate, a resin film substrate, a semiconductor substrate, or the like. A plurality of stacked bodies 20A are formed by forming a plurality of stacked bodies 20B on the lower surface at positions opposite to the stacked body 20A. A transparent insulating layer 30 is inserted between the stacked bodies 20 (that is, the stacked body 20A and the stacked body 20B).

  The stacked body 20 has a structure in which an electron injection layer 22 and an organic layer 23 serving as a light emitting source are sandwiched between a cathode 11 a or a cathode 21 and an anode 24, and each layer is stacked on the element substrate 10. It becomes.

  The cathodes 11a and 21 function as electron injection electrodes. The cathode 11a is a cathode corresponding to the lowermost layer in the light emitting direction among the layers constituting the organic EL element 1, and is formed on the lower surface of the element substrate 10 as the uppermost layer of the stacked body 20B. Since the cathode 11a is arranged on the side opposite to the light emission side, it is a metal electrode made of aluminum or the like having high reflectivity in order to increase the light extraction efficiency. Since the cathode 21 is a cathode other than the cathode 11a and is disposed on the light emission side, the cathode 21 is a transparent electrode using a high transmittance transparent conductive material (for example, ITO or titanium nitride) in order to increase the light extraction efficiency. The

  The electron injection layer 22 is a buffer layer provided between the light emitting layer and the cathode, and has a function of enhancing the bonding property between the light emitting layer and the cathode and increasing the electron injection efficiency. Here, since it is difficult to select a material having a low work function for the transparent cathode 21, it is necessary to increase the electron injection efficiency by providing the electron injection layer 22. As a material for the electron injection layer 22, for example, a co-deposited film of bathocuproine and cesium, a co-deposited film of magnesium and silver, LiF / Ca / Al, or the like can be used.

  The organic layer 23 is a single-layer or multilayer organic thin film including a light-emitting layer, and includes, for example, a hole injection / transport layer. The light emitting layer is a layer in which light is generated by recombination of electrons and holes injected from the cathode 11 a or 21 and the anode 24. The hole injection layer is a buffer layer provided between the light emitting layer and the anode 24 and improves the bonding property between the light emitting layer and the anode 24. The hole transport layer has a function of increasing the hole injection efficiency and increasing the moving speed of the injected holes. As the organic compound for forming the hole injection / transport layer, for example, a mixture of a polythiophene derivative such as polyethylenedioxythiophene and polystyrene sulfonic acid can be used. The configuration of the organic layer 23 is not particularly limited except that it includes a light emitting layer.

  Since the anode 24 functions as a hole injection electrode and is located on the light emission side, it is a transparent electrode made of, for example, ITO.

The transparent insulating layer 30 is provided to electrically partition the stacked bodies 20 and is formed from a transparent insulating material such as SiO ₂ , SiN _X , AlO _{2 and the} like in order to be disposed between the layers. The effect of the transparent insulating film 30 will be described later.

  In the present embodiment, the cathode 21 and the anode 24, which are transparent electrodes, and the transparent insulating layer 30 are each formed by an ion plating method. Therefore, the risk of damaging the electron injection layer 22 and the organic layer 23 during these film formations is avoided, and the manufacture of the organic EL element 1 having such a structure is practically possible.

  The stacked body 20 </ b> A is configured by stacking an anode 24, an organic layer 23, an electron injection layer 22, and a cathode 21 in this order on one surface of the element substrate 10. The stacked body 20 </ b> B is configured by stacking the anode 24, the organic layer 23, the electron injection layer 22, and the cathode 11 a or 21 in this order on the other surface of the element substrate 10. Here, since these laminated bodies 20 are laminated via the transparent insulating layer 30, each can be connected in parallel to the power source. Accordingly, each stacked body 20 is driven by a current flowing through a different current path for each stacked body 20 under the same voltage applied from the power source. FIG. 1 shows a case where wiring and power supplies 50A and 50B are provided on the upper surface side and the lower surface side of the element substrate 10 to drive the stacked body 20A and the stacked body 20B separately. May be shared on both sides of the element substrate 10.

  In the organic EL element 1, any light generated in the organic layer 23 of each stacked body 20 is extracted from the upper surface side of the element substrate 10 to the outside of the element. At this time, if the stacked body 20 is driven simultaneously, the light emitted from each stacked body 20 is emitted in an overlapping manner, so that the light emission luminance as the organic EL element 1 is doubled according to the number of the stacked bodies 20. . Therefore, according to the organic EL element 1, it is possible to emit light or display with high luminance. At the same time, in such an organic EL element 1, the amount of current supplied to each stacked body 20 can be relatively suppressed. Therefore, the lifetime of the element can be extended.

  In the organic EL element 1, each stacked body 20 is connected in parallel to the power source 50, and the driving voltage is constant regardless of the number of the stacked bodies 20. An existing power supply can be used instead of a power supply. If three laminated bodies 20 are connected in series to a power source and driven, if the applied voltage to each laminated body 20 is, for example, 10V, the drive voltage of the entire element is 30V. In this case, since an existing drive circuit cannot be used, a drive circuit for high voltage is required. In other words, the drive circuit side is inevitably modified. In addition, since the high-voltage drive circuit is quite expensive, the cost of the device using this element is greatly increased. On the other hand, when the stacked bodies 20 are connected in parallel as in the organic EL element 1 of the present embodiment, if the applied voltage to the stacked body 20 is, for example, 10V, the drive voltage of the entire element is also within 10V. Such a problem does not occur and can be widely applied to various apparatuses.

  Furthermore, since the organic EL element 1 is configured by laminating the laminated body 20 using both surfaces of the element substrate 10, it is easy to form a laminated structure. For example, when four laminates are laminated on one side of the substrate and two on each side of the substrate, the former is structurally more difficult to manufacture even though the light emission luminance as the element is the same. Is expensive. In other words, the more laminated the layers, the more difficult it is to form a layered structure, and the circuit layout such as the lead-out wiring becomes complicated, making it difficult to manufacture while maintaining the characteristics and reliability of the elements. It becomes. On the other hand, in the present embodiment, it is only necessary to form fewer stacked bodies 20 on the respective surfaces of the element substrate 10 than the number of layers to be originally stacked. Can be doubled. Therefore, according to the organic EL element 1, it is possible to reduce manufacturing problems caused by an increase in the number of stacked layers while achieving high luminance by stacking.

<1-2: Bottom emission type organic EL element>
In FIG. 2, the organic EL element 2 is a bottom emission type light emitting element that extracts light from the lower surface side of the element substrate 10. The cathode 11b is a cathode corresponding to the lowermost layer in the light emitting direction among the layers constituting the organic EL element 2, and is formed on the upper surface of the element substrate 10 as the uppermost layer of the stacked body 20A. Since the element substrate 10 is disposed on the light emitting side, the element substrate 10 is a transparent substrate such as a glass substrate or a resin film substrate.

  Also in this organic EL element 2, since the laminated body 20 is laminated on both surfaces of the element substrate 10, and each laminated body 20 is connected in parallel to the power sources 50A to 50B, the organic EL element 1 and The same operation and effect are exhibited.

<1-3: Double-sided light emitting organic EL device>
In FIG. 3, the organic EL element 3 is configured in substantially the same manner as the organic EL element 1. However, in this case, as the uppermost layer on the lower surface side of the element substrate 10, a cathode 21 made of a transparent conductive material is formed instead of the metal cathode 11a. Therefore, the organic EL element 3 can simultaneously extract light from both sides of the element substrate 10.

  The configuration of the organic EL element 3 is the same as that of the organic EL element 1 except for the above, and exhibits the same operations and effects as the organic EL element 1.

<2: Manufacturing method of organic EL element>
Next, with reference to FIG.4 and FIG.5 further, the manufacturing method of the organic EL element which concerns on this embodiment is demonstrated. FIG. 4 shows a schematic configuration of a film forming apparatus applied to the manufacturing method according to the present embodiment. FIG. 5 is a flowchart showing a method for manufacturing an organic EL element according to this embodiment. In the following, a case where the “bottom emission type” organic EL element 2 is manufactured will be described as a typical example, but elements of other aspects can be manufactured by substantially the same method.

<2-1: Film forming apparatus>
Before describing a specific manufacturing process, the configuration of the film forming apparatus 200 according to the present embodiment will be described.

  In FIG. 4, a film forming apparatus 200 connects a vacuum deposition apparatus 201, an ion plating apparatus 202, and between the vacuum deposition apparatus 201 and the ion plating apparatus 202, and transports the element substrate 10 between the apparatuses. The vacuum transfer chamber 203 is generally configured. Vacuum gates 204a and 204b are disposed at the junction between the vacuum deposition apparatus 201 and the vacuum transfer chamber 203 and at the junction between the ion plating apparatus 202 and the vacuum transfer chamber 203, respectively.

  In the vacuum vapor deposition apparatus 201, a base part 211 on which the film forming material 210 is placed and a heating apparatus 212 such as a heater for heating and evaporating the film forming material 210 are arranged at the bottom of the apparatus. On the other hand, a substrate holding unit (not shown) is disposed at a position facing the base unit 211, and the element substrate 10 is conveyed to the substrate holding unit and disposed. Further, an openable / closable shutter 213 is disposed between the base portion 211 and the element substrate 10 to block a path through which the evaporated film forming material 210 reaches the element substrate 10.

  Further, the vacuum deposition apparatus 201 is configured so that the internal vacuum degree is maintained by sucking and exhausting the gas by the exhaust apparatus 220 including the vacuum gate 220a and the exhaust pump 220b.

  The ion plating apparatus 202 exhausts the gas in the plasma generation unit 250, the film formation unit 260 that performs film formation, the substrate transfer unit 270 that transfers the element substrate 10 stacked up to the electron injection layer 15, and the film formation unit 260. And an exhaust device 280 to be configured.

  The plasma generation unit 250 includes a DC power source 251, a magnetic field generation coil 252, and a discharge anode 253, and has a function of converting the introduced argon gas into plasma and introducing it into the film forming material 261. In the film forming unit 260, a base unit 262 for mounting a film forming material 261 such as ITO and a gas supply unit 263 for supplying an atmospheric gas are arranged, and the element substrate 10 is arranged at a position facing the base unit 262. Is done.

  Further, the ion plating apparatus 202 is configured such that the internal vacuum degree is maintained by sucking and exhausting gas by an exhaust apparatus 280 including a vacuum gate 280a and an exhaust pump 280b. The ion plating apparatus 202 has a configuration in which the element substrate 10 is disposed outside the plasma generation region. As will be described later, the element substrate 10 is directly applied to the plasma when the cathode 21 as the transparent conductive layer is formed. Since it is not exposed, an organic EL element having high luminance and high reliability can be obtained without damaging the lower organic layer 23 and the electron injection layer 22.

  The vacuum transfer chamber 203 is provided with an exhaust device 230 composed of a vacuum gate 230a and an exhaust pump 230b, and is configured to be able to exhaust a gas and maintain the degree of vacuum inside.

  Here, the film forming apparatus 200 is used to form the stacked body 20 on both surfaces of the element substrate 10. That is, in the film forming apparatus 200, after the stacked body 20A is formed on one surface, the element substrate 10 on which the stacked body 20A is formed is held or transported in order to form the stacked body 20B on the other surface. There is a case. In order to prevent damage to the stacked body 20 </ b> A at that time, a protective film may be provided so as to cover one surface, and the substrate holding mechanism and the transport mechanism in the film forming apparatus 200 are configured to hold the periphery of the element substrate 10. Also good.

<2-2: Manufacturing process>
Next, each manufacturing process of the organic EL element 2 using the film forming apparatus 200 will be specifically described.

  In the flowchart of FIG. 5, first, the stacked body 20 </ b> A is stacked on the upper surface of the element substrate 10. Using the ion plating apparatus 202, the anode 24 as a transparent conductive layer is formed on the upper surface of the element substrate 10 (step S11). That is, the element substrate 10 is disposed at a position facing the base 262 and the argon plasma generated by the plasma generation unit 250 is introduced to evaporate the film forming material 261 such as ITO, and the upper surface of the element substrate 10. Deposit.

  Next, the organic layer 23 is formed on the anode 24 (step S12). The organic layer 23 includes, for example, a hole injection / transport layer and a light emitting layer, and can be formed by a vacuum deposition method or a coating method such as a spin coating method or an ink jet method depending on the material of each layer. Therefore, the element substrate 10 is transferred from the ion plating apparatus 202 to the vacuum deposition apparatus 201 through the vacuum transfer chamber 203 before the organic layer 23 is formed. Alternatively, when the organic layer 23 is formed by a coating method, the element substrate 10 is once taken out from the film forming apparatus 200.

  The hole injecting / transporting layer formed as the organic layer 23 is formed, for example, by discharging a composition containing a hole injecting / transporting layer forming material with an ink jet apparatus and performing a drying process and a heat treatment.

  The formation of the light emitting layer includes, for example, a surface modification process, a light emitting layer forming material discharge process, and a drying process. In the surface modification step, a surface modifying material that is the same solvent as the non-polar solvent of the composition used for forming the light emitting layer or a similar solvent is injected into the hole by an ink jet method, a spin coat method, or a dip method. It is carried out by drying after coating on the transport layer. As the surface modifier, for example, cyclohexylbenzene, dihydrobenzofuran, trimethylbenzene, tetramethylbenzene and the like can be adopted as the same nonpolar solvent of the composition, and as a nonpolar solvent of the composition, for example, toluene Xylene or the like can be used. In the light emitting layer forming material discharging step, a composition containing the light emitting layer forming material is discharged onto the hole injection / transport layer by an inkjet method. Then, it dries and evaporates the nonpolar solvent contained in a composition, precipitates a light emitting layer forming material, and forms a light emitting layer. The formation of the organic layer 23 is preferably performed in an atmosphere free from water vapor and oxygen, and the operation is preferably performed in an inert gas atmosphere such as nitrogen or argon.

  After the formation of the organic layer 23, the element substrate 10 outside the film forming apparatus 200 is transferred into the vacuum vapor deposition apparatus 201 and placed at a predetermined position.

  Next, the electron injection layer 22 is formed on the organic layer 23 using the vacuum evaporation apparatus 201 (step S13). The inside of the vacuum evaporation apparatus 201 is kept in a predetermined vacuum state by the exhaust apparatus 220. The film forming material 210 placed on the base 211 is heated and evaporated by the heating device 212 and deposited on the organic layer 23. The thickness of the formed electron injection layer 22 can be adjusted by closing the shutter 213 and blocking the path through which the evaporated film forming material 210 reaches the element substrate 10.

  Here, in FIG. 5, it is assumed that n stacks 20A (where n is a natural number of 2 or more) are stacked, and the stacked body 20 formed halfway at this time is the Yth (that is, At present, Y = 1). As will be described later, the series of steps described here is repeated n times. At that time, the cathode 21 and the transparent insulating layer 30 are formed (step S14: Y) until the formation of the uppermost laminate 20 is started (step S14: N), as will be described later.

  Next, the element substrate 10 formed up to the electron injection layer 22 is transported from the vacuum deposition apparatus 201 to the ion plating apparatus 202 (step S15). Specifically, the gas in the vacuum transfer chamber 203 is evacuated in advance by an exhaust device 230 including a vacuum gate 230a and an exhaust pump 230b, and the vacuum transfer chamber 203 is placed in a vacuum state similar to that of the vacuum vapor deposition device 201. . After the formation of the electron injection layer 22, the vacuum gate 204a is opened, the element substrate 10 is transferred from the vacuum deposition apparatus 201 to the vacuum transfer chamber 203, and the vacuum gate 204a is closed. At this time, the inside of the ion plating apparatus 202 is also evacuated by the exhaust apparatus 280, and the same vacuum state is set. Subsequently, the vacuum gate 204b is opened, the element substrate 10 is transferred from the vacuum transfer chamber 203 to the ion plating apparatus 202, and the vacuum gate 204b is closed.

  By doing so, after forming the electron injection layer 22 by the vacuum deposition method, it is possible to proceed to the next step of forming the cathode 21 while maintaining a predetermined vacuum state. For this reason, it becomes possible to prevent oxidation of the surface of the electron injection layer 22 and adsorption of other unnecessary gases.

  Next, the cathode 21 which is a transparent conductive layer is formed on the electron injection layer 22 using the ion plating apparatus 202 (step S16). For example, the cathode 21 can be divided into an upper layer and a lower layer as follows. First, a lower layer made of ITO is formed on the electron injection layer 22. In this case, ITO is placed on the base 262 as the film forming material 261, and ITO is deposited on the entire surface of the electron injection layer 22 in an argon gas atmosphere not containing oxygen, thereby forming a lower layer. Argon gas is introduced into the plasma generation unit 250, converted into argon plasma by the DC power supply 251, and introduced into the film forming material 261 on the base 262 by the magnetic field generation coil 252 and the discharge anode 253. ITO evaporates when heated by argon plasma. The evaporated ITO is deposited on the electron injection layer 22 in an argon gas atmosphere.

  Here, when the lower layer is deposited, no bias is applied between the film forming material 261 and the element substrate 10. Therefore, the evaporated film forming material 261 is deposited without being accelerated. By not accelerating the film forming material, damage to the film on which the film forming material is deposited, the electron injection layer 22 serving as the base, and the like can be suppressed.

  When film formation of the lower layer is completed, oxygen is subsequently introduced into the film forming unit 260 to form the upper layer. Oxygen gas is introduced into the inside from the gas supply unit 263 to create an argon gas atmosphere containing oxygen. The evaporated ITO is combined with oxygen gas, and an upper layer of low resistance and high transmittance containing a large amount of oxygen is formed. Thus, the cathode 21 is formed.

  Through the above steps, the first stacked body 20A is completed on one surface of the element substrate 10.

Next, using the ion plating apparatus 202, the transparent insulating layer 30 is formed on the cathode 21 (step S17). The transparent insulating film 30 is formed in the same manner as the cathode 21 except that a transparent insulating material such as SiO ₂ , SiN _x , and AlO ₂ is used as the film forming material 261.

  Thereafter, in the same manner as described above, the formation process of the stacked body 20 and the formation process of the transparent insulating layer 30 are repeated. At this time, when the cathode 21, the transparent insulating layer 30, and the anode 24 are sequentially formed, these layers are continuously formed by using the ion plating apparatus 202, so that the deposition throughput can be improved. it can.

  In the step of forming the n-th, that is, the uppermost laminate 20 (ie, Y = n), when the anode 24, the organic layer 23, and the electron injection layer 22 are formed as described above, the cathode 11b The process proceeds to the formation process (step S14: N). In the case of the organic EL element 2 shown in FIG. 2, since the two stacked bodies 20A are stacked, the above-described series of steps is executed only once, and the uppermost stacked body 20A (ie, Y = 2) In the forming step, the cathode 11b is formed instead of the cathode 21.

  That is, as the uppermost layer of the organic EL element 2, the cathode 11b is formed on the electron injection layer 22 using the vapor deposition apparatus 201 (step S18). Therefore, the cathode 11 b can be continuously deposited following the electron injection layer 22. As the film forming material 210 in this case, for example, a metal material containing aluminum (Al), or calcium (Ca), lithium fluoride (LiF), strontium fluoride (SrF2), magnesium (Mg), silver (Ag) A metal material containing at least one of the above is used.

  The formation of the stacked body 20A is completed through the above steps. In addition, following the step of forming the cathode 11b, a sealing film made of silicon oxynitride or the like may be formed on the cathode 11b by the ion plating apparatus 202. Specifically, first, the gas in the film forming unit 260 is exhausted by the exhaust device 280. Subsequently, an atmospheric gas such as nitrogen gas is introduced from the gas supply unit 263 into the film forming unit 260. Further, the film forming material 261 is exchanged from ITO to silicon oxide. Argon gas is introduced into the plasma generation unit 250, converted into argon plasma by the DC power supply 251, and introduced into the film forming material 261 on the base 262 by the magnetic field generation coil 252 and the discharge anode 253. Silicon oxide is heated by argon plasma and evaporated. The evaporated silicon oxide particles are ionized by argon plasma, enter a state of high activity and enter the surface of the cathode 11b. The silicon oxide deposited on the cathode 11b reacts with the nitrogen gas in the atmospheric gas to become silicon oxynitride, so that a dense and uniform sealing film can be formed. This sealing film can also function as a protective film in the next step.

  Next, a protective film is provided so as to cover the upper surface side of the element substrate 10 (step S18). The protective film is provided for the purpose of preventing damage to the stacked body 20A formed on the element substrate 10 in the following steps. For example, the protective film may be formed on the element substrate 10 like a sealing film. Alternatively, a resin film or the like may be temporarily attached.

  Next, the element substrate 10 is inverted (step S19), and the stacked body 20B is subsequently laminated on the lower surface of the element substrate 10. In FIG. 5, m stacked bodies 20B (where m is a natural number of 2 or more) are stacked, and a series of steps for forming the stacked body 20B is repeated m times (step S26). In addition, this series of processes is the same as the formation process of the stacked body 20A, the formation process of the anode 24 (step S21), the formation process of the organic layer 23 (step S22), the formation process of the electron injection layer 22 (step S23), The element substrate 10 is transported (step S24) and the cathode 21 is formed (step S25) in this order. Each step can be performed as described above. Then, when the uppermost laminate 20B is formed (step S26: N), all the processes are completed. Incidentally, in the organic EL element 2, two stacked bodies 20A and 20B are stacked, but the number of stacked bodies 20A (that is, n) and the number of stacked bodies 20B (that is, m) are not necessarily the same. Not necessary.

  As described above, the organic EL element 2 is completed.

  As described above, according to the method of manufacturing the organic EL device in the present embodiment, since the stacked body 20 is stacked on both surfaces of the element substrate 10, such a stacked structure is relatively easy even when the number of stacked layers is large. It is possible to manufacture a highly reliable device.

  Further, since the anode 24 and the cathode 21, which are the transparent electrode layers, and the transparent insulating layer 30 are formed by the ion plating apparatus 202, the electron injection layer 22 and the organic layer 23 are not damaged and are caused by the damage. Thus, it is possible to obtain the organic EL element 2 having high luminance and high reliability. In particular, the present ion plating apparatus 202 has a structure in which the element substrate 10 is arranged outside the plasma generation region, so that the element substrate 10 is not directly exposed to the plasma, so that the light emitting layer and the electron injection layer are damaged. There is little or no practice.

  Further, since the anode 24, the cathode 21, and the transparent insulating layer 30 are formed by the same ion plating apparatus 202, three film forming processes can be continuously performed, and a process such as transporting a substrate can be performed. The film formation throughput can be improved.

  Furthermore, in the formation process of each laminated body 20, after forming the electron injection layer 22 with the vacuum evaporation apparatus 201, the element substrate 10 is placed in a vacuum atmosphere and transported, and the cathode by the ion plating apparatus 202 as the next process. Since the process shifts to the formation of 21, the oxidation of the electron injection layer 22 can be prevented. Therefore, the characteristics of the electron injection layer 22 are not deteriorated, and as a result, it is possible to manufacture the organic EL element 2 having good characteristics.

<3: Organic EL device>
Next, with reference to FIGS. 6 to 8, an embodiment according to an organic EL device including the organic EL element of the above embodiment will be described. In the following, the case where the “bottom emission type” organic EL element 2 as shown in FIG.

<3-1: Overall configuration of organic EL device>
The overall configuration of the organic EL device will be described with reference to FIG. FIG. 6 is a schematic plan view of the organic EL device when the element substrate 10 is viewed from the sealing substrate side. Here, an active matrix driving type organic EL device with a built-in driving circuit is taken as an example.

  In FIG. 6, a plurality of pixel driving signal lines 116 a are wired in the image display region 110 on the element substrate 10, and a plurality of pixel portions that are electrically connected to the pixel driving signal lines 116 a are predetermined. Arranged in a pattern. Each of the plurality of pixel portions includes an organic EL element 2. In FIG. 6, the specific configuration of the pixel driving signal line 116a and the pixel portion in the image display area 110 is not shown, and details thereof will be described later.

  In the peripheral region located around the image display region 110, a Y-side drive circuit unit 132 is provided along two sides of the element substrate 10 facing each other with the image display region 110 interposed therebetween, and is adjacent to the two sides. An X-side drive circuit unit 152 is provided along one side. The plurality of pixel driving signal lines 116 a are electrically connected to the Y side driving circuit unit 132 and the X side driving circuit unit 152. In FIG. 6, among the plurality of pixel drive signal lines 116 a, the pixel drive signal line 116 a electrically connected to the X side drive circuit unit 152 is connected to the X side drive circuit unit 152 from one side of the image display region 110. A portion of the wiring extending and extending is shown.

  Furthermore, a plurality of mounting terminals 102 are provided along one side of the element substrate 10 on which the X-side drive circuit unit 152 is provided. The wiring substrate 300 is mounted on these mounting terminals 102 by, for example, a TAB (Tape Automated Bonding) method or a COG (Chip On Grass) method. The wiring substrate 300 is formed with an external circuit that supplies various signals for driving the scanning line driving circuit and the data line driving circuit.

  The Y-side drive circuit unit 132 is provided with a scanning line driving circuit, and for example, wiring for electrically connecting the pixel driving signal line 116a to circuit elements in the scanning line driving circuit, and scanning line driving. Wiring and the like serving as a supply path for various signals for driving the circuit are provided. The X-side drive circuit unit 152 is provided with a data line drive circuit, and for example, wiring for electrically connecting the pixel drive signal line 116a and circuit elements in the data line drive circuit, data line drive, and the like. Wiring and the like serving as a supply path for various signals for driving the circuit are provided. The wiring 116 b is electrically connected to the input / output signal line 118 through the X-side drive circuit unit 152.

  A plurality of types of input / output signal lines 118 are provided corresponding to the types of signals input to and output from the external circuit. For example, the plurality of input / output signal lines 118 are provided with a pixel driving power line 118a and a driving circuit signal line as described below. The pixel driving power supply line 118a is supplied with pixel driving power from an external circuit.

  Here, as described above, since the drive voltage of the organic EL element 2 does not increase regardless of the number of the stacked bodies 20 as described above, for example, an existing power supply is used instead of a high-voltage power supply. Can do. One end side of the pixel driving power line 118a is electrically connected to a power supply line as the pixel driving signal line 116a via the X side driving circuit unit 152 or the Y side driving circuit unit 132.

  A driving circuit signal for driving the scanning line driving circuit and the data line driving circuit is supplied from an external circuit to the driving circuit signal line. For example, as shown in FIG. 6, the driving circuit signal line is supplied with driving circuit power that serves as a power source for the scanning line driving circuit and the data line driving circuit. A power supply line 118b is included.

<3-2: Configuration of Pixel Unit>
Next, referring to FIGS. 7 and 8 in addition to FIG. 6, the configuration of the pixel portion in the image display area 110 of the organic EL device will be specifically described. FIG. 7 is a block diagram showing the overall configuration of the organic EL device, and FIG. 8 is a cross-sectional view of an arbitrary pixel portion on the element substrate on which data lines, scanning lines, organic EL elements and the like are formed.

  First, the electrical configuration of the image display area 110 of the organic EL device will be described with reference to FIG.

  In the image display region 110 on the upper surface side of the element substrate 10, data lines 114 and scanning lines 112 corresponding to the pixel driving signal lines 116 a in FIG. 6 are extended vertically and horizontally, and each pixel unit 70 corresponding to the intersection thereof. Are arranged in a matrix. Further, power supply lines 117 corresponding to the pixel units 70 arranged for the respective data lines 114 extend in the image display area 110. The power supply line 117 also corresponds to the pixel drive signal line 116a in FIG.

  In this embodiment, in order to perform color display, the image display area 110 is provided with, for example, three types of pixel portions 70 for R, G, and B, and corresponds to the three types of pixel portions 70. Three kinds of data lines 114 and three kinds of power supply lines 117 are provided. In FIG. 7, for example, three types of pixel portions 70 are provided for every three adjacent data lines 114. Among the three data lines 114, any one of the three types of pixel units 70 is arranged on any one of the data lines 114. In addition, corresponding types of power supply lines 117 are electrically connected to the pixel units 70 arranged in this way.

  As described above, the scanning line driving circuit 130 and the data line driving circuit 150 are provided in the peripheral region on the element substrate 10. The scanning line driving circuit 130 and the data line driving circuit 150 are driven based on a driving circuit signal supplied from an external circuit through the mounting terminal 102 and the driving circuit signal line as the input / output signal line 118 in FIG. Is done. Then, the scanning line driving circuit 130 sequentially supplies scanning signals to the plurality of scanning lines 112. The data line driving circuit 150 supplies three types of image signals for R, G, and B to the three types of data lines 114 wired in the image display area 110. The operations of the two types of scanning line driving circuits 130 and the operation of the data line driving circuit 150 are synchronized with each other by a synchronization signal 160 supplied from an external circuit.

  In the peripheral region, three types of pixel driving power lines 118 a are provided corresponding to the three types of power supply lines 117. Each of the three types of power supply lines 117 is supplied with pixel driving power from an external circuit via the mounting terminal 102 and the corresponding pixel driving power supply line 118a.

  Here, if attention is paid to one pixel portion 70 in FIG. 7, the organic EL element 2 is provided in the pixel portion 70 and, for example, a switching transistor 76 and a driving transistor 74 configured using TFTs, In addition, a holding capacitor 78 is provided. In the pixel unit 70, each transistor is configured by, for example, a thin film transistor (hereinafter referred to as “TFT” as appropriate).

  The scanning line 112 is electrically connected to the gate electrode of the switching transistor 76, the data line 114 is electrically connected to the source electrode of the switching transistor 76, and the drain electrode of the switching transistor 76 is connected to the drain electrode of the switching transistor 76. The gate electrode of the driving transistor 74a is electrically connected.

  Here, the source electrodes of the driving transistor 74 a are both electrically connected to the power supply line 117. The anode of the stacked body 20A constituting the organic EL element 2 is electrically connected in parallel to the drain electrode of the driving transistor 74a.

  On the lower surface side of the element substrate 10, the same structure as that of the upper surface side is configured to be mirror-symmetric with respect to the element substrate 10. Among them, the gate electrode of the driving transistor 74 b is electrically connected to the drain electrode of the switching transistor 76. The anode of the stacked body 20B is electrically connected in parallel to the drain electrode of the driving transistor 74b. Thus, the stacked bodies 20A and 20B are connected in parallel to the power supply line 117 via the driving transistors 74a and 74b, respectively.

  In such an organic EL device, in addition to the configuration of the pixel circuit illustrated in FIG. 7, a current program type pixel circuit, a voltage program type pixel circuit, a voltage comparison type pixel circuit, and a subframe type pixel are provided. It is possible to employ various types of pixel circuits such as circuits.

  Next, a more detailed configuration of the pixel unit 70 will be described with reference to FIG.

  For example, the semiconductor layer 3 of the switching transistor 76 and the driving transistor 74a is formed on the upper surface of the element substrate 10 configured using a transparent substrate such as a transparent resin or a glass substrate. The semiconductor layer 3 is formed using, for example, a low-temperature polysilicon film. On the semiconductor layer 3, the gate insulating layer 2 of the switching transistor 76 and the driving transistor 74a is formed so as to embed the semiconductor layer 3. On the gate insulating layer 2, the gate electrode 3a of the driving transistor 74 and the scanning line 112 (not shown here) are formed as the same film. The gate electrode 3a and the scanning line 112 are made of a metal material containing at least one of Al (aluminum), W (tungsten), Ta (tantalum), Mo (molybdenum), Ti (titanium), copper (Cu), and the like. Is formed.

  An interlayer insulating layer 41 is formed on the gate insulating layer 2 so as to embed the scanning line 112 and the gate electrode 3a of the driving transistor 74a. The interlayer insulating layer 41 and the gate insulating layer 2 are made of, for example, a silicon oxide film.

  On the interlayer insulating layer 41, the power supply line 117, the drain electrode 42 of the driving transistor 74a, and the data line 114 (not shown here) are formed as the same film. These are each comprised from the electrically-conductive material which contains aluminum (Al) or ITO (Indium Tin Oxide), for example. Contact holes 501 and 502 are formed in the interlayer insulating layer 41 so as to penetrate the interlayer insulating layer 41 and the gate insulating layer 2 and reach the semiconductor layer 3 of the driving transistor 74a. As shown in FIG. 8, the conductive film constituting the power supply line 117 and the drain electrode 42 is continuously formed so as to reach the surface of the semiconductor layer 3 along the inner walls of the contact holes 501 and 502. .

  On the interlayer insulating layer 41, for example, a silicon nitride film (SiN) is formed as the protective layer 45 so as to embed the power supply line 117 and the drain electrode 42. On the protective layer 45, an opening region in the pixel portion 70 is formed between the banks formed by the insulating layers 46 and 47. Two stacked bodies 20A are stacked in the opening region. The formation procedure is in accordance with the manufacturing method described above.

  Between the banks of the insulating layers 46, the anode 24, the organic layer 23, the electron injection layer 22, and the cathode 21 are stacked in this order with the protective layer 45 as a base. The anode 24 is formed using ITO as a transparent conductive material so as to extend from the opening region and overlap with a part of the drain electrode 42. An organic layer 23 is formed on the anode 24. Among them, the light emitting material of the light emitting layer is selected according to R, G and B of the organic EL element 2. The cathode 21 is formed using a transparent conductive material, and is drawn out of the opening region and grounded.

  On the upper layer side, a transparent insulating layer 30 is formed on one surface. Between the banks of the insulating layers 47, the anode 24, the organic layer 23, the electron injection layer 22 and the cathode 11b are formed with the transparent insulating layer 30 as a base. They are stacked in order. The anode 24 extends from the opening region and is formed so as to overlap with a part of the drain electrode 42 through a contact hole. The light emitting material of the upper organic layer 23 is the same material as that of the lower organic layer 23. The cathode 11b is drawn out of the opening area and grounded. In FIG. 7, the sealing substrate is not shown.

  On the other hand, on the lower surface of the element substrate 10, the same structure as that on the upper surface side is configured to be mirror-symmetric with respect to the element substrate 10. That is, the driving transistor 74b is formed immediately above the element substrate 10, and two stacked bodies 20B are stacked on the interlayer insulating layer 51 and the protective layer 55 as a base. Each stacked body 20 </ b> B is formed in an opening region formed by a bank including the insulating layers 56 and 57. Here, the opening region on the upper surface of the element substrate 10 and the opening region on the lower surface are opened at positions opposite to each other, and the stacked body 20A and the stacked body 20B are as if they are continuous through the element substrate 10. It is arranged as if.

  In this type of organic EL device, it is desirable that the pixel aperture ratio is high, and the area of each pixel tends to be as small as possible for high definition. Accordingly, the pixel portion as shown in FIG. 8 is fine, and elements such as wirings and transistors are formed in a limited region around the opening region. For this reason, when the number of stacked layers 20 increases, it becomes a problem how to route the lead-out wiring from the cathode 21 and the anode 24. In that case, the circuit layout becomes complicated anyway, and it becomes difficult to manufacture while maintaining the characteristics and reliability of the element. In addition, if the number of layers stacked on one side increases, as shown in FIG. 8, more margin is actually required for the opening region, and the opening ratio may be reduced.

  On the other hand, in the organic EL element 2, four laminated bodies 20 are distributed to each surface of the element substrate 10, and twice the space for the lead-out wiring is secured as compared with the case where the laminated body is formed only on one side of the substrate. It is not necessary to widen the margin of the opening region so much. Therefore, manufacturing problems caused by an increase in the number of stacked layers are reduced.

  Therefore, the organic EL device of this embodiment has high luminance and high reliability, and can be manufactured relatively easily. In addition, although it is a structure in which the light emitting units are stacked, it can be configured without using an expensive high-voltage power supply, and thus can be widely applied as various devices.

<3-3: Operation of Organic EL Device>
When the organic EL device is driven, scanning signals are supplied via scanning lines 112 on both sides of the element substrate 10. As a result, the switching transistor 76 is turned on. Therefore, the image signal supplied from the data line 114 is applied to the gate of the driving transistor 74 and written to the storage capacitor 78. At this time, the driving transistor 74 is turned on, and a driving current is applied from the power supply line 117 to the organic EL element 2 via the driving transistor 74. At this time, since the gate voltage of the driving transistor 74 is fixed by the image signal written in the storage capacitor 78, a constant current corresponding to the image signal flows on the organic EL element 2 side.

  Here, since the stacked bodies 20A and the stacked bodies 20B of the organic EL element 2 are connected in parallel to the drain electrode 42, the same current flows in each of the stacked bodies 20A and 20B. , Emits light in the same way.

  The light generated in the light emitting layer is extracted from the lower surface side of the element substrate 10 (in the direction of arrow X in FIG. 8). At this time, since a total of four stacked bodies of the stacked bodies 20A and 20B emit light at the same time, the luminous efficiency is simply quadrupled and the luminance is increased.

  On the contrary, the organic EL element 2 in the present embodiment can obtain the same luminance as the conventional one even if the drive current is reduced, and can extend the lifetime of the element by the decrease in current. Alternatively, it contributes to lower power consumption.

<3-4: Second Embodiment of Organic EL Device>
Next, another embodiment of the organic EL device of the present invention will be described with reference to FIG. FIG. 9 conceptually shows the configuration of the pixel portion of the organic EL device according to the second embodiment.

  In FIG. 9, the organic EL element 2 ′ in the pixel portion is a “bottom emission type” similar to the organic EL element 2, and the two stacked bodies 20A are connected in parallel to the power source 50A. The individual stacked bodies 20B are connected in parallel to the power supply 50B. A specific configuration of the pixel portion including the organic EL element 2 ′ is generally configured as shown in FIGS. 7 and 8.

  Since the stacked bodies 20 connected in parallel have independent current paths, in principle, they can be driven independently of each other. Therefore, in the organic EL device of the present embodiment, the switching elements 61, 62, 63 and 64 are provided between the respective anodes of the stacked body 20 and the power sources 50A to 50B, and the stacked body 20 is independently driven and controlled. It is configured to be. The switching elements 61 to 64 may be TFTs such as the driving transistor 74, for example. In this case, if the laminate 20 is driven so as to be interlocked with the light emission time and the amount of drive current, it contributes to extending the life of the element.

  In the above embodiment, the bottom emission type organic EL device has been described. However, the organic EL device of the present invention emits light emitted from the organic EL element 1 (see FIG. 1) as display light from the sealing substrate side. It may be configured as a top emission type.

<4: Electronic equipment>
Next, an electronic apparatus to which the organic EL device of the above embodiment is applied will be described with reference to FIGS.

<4-1: Mobile computer>
First, an example in which the above-described organic EL device is applied to a mobile personal computer will be described. FIG. 10 is a perspective view showing the configuration of this personal computer. In FIG. 10, a computer 1200 includes a main body 1204 including a keyboard 1202 and a display unit 1206 configured using an organic EL device.

<4-2: Mobile phone>
Further, an example in which this organic EL device is applied to a mobile phone will be described. FIG. 11 is a perspective view showing the configuration of this mobile phone. In FIG. 11, a cellular phone 1300 includes an organic EL device together with a plurality of operation buttons 1302.

  In addition, the organic EL device according to the embodiment includes a notebook personal computer, a PDA, a television, a viewfinder, a monitor direct-view video tape recorder, a car navigation device, a pager, an electronic notebook, a calculator, a word processor, a work The present invention can be applied to an apparatus including a station, a POS terminal, a touch panel, and a printer.

  The present invention is not limited to the above-described embodiments, and can be appropriately changed without departing from the gist or philosophy of the invention that can be read from the claims and the entire specification, and an organic EL element accompanied by such a change. , And an organic EL device provided with the same are also included in the technical scope of the present invention.

It is sectional drawing which shows the 1st basic composition of the organic EL element which concerns on embodiment of this invention. It is sectional drawing which shows the 2nd basic composition of the organic EL element which concerns on embodiment of this invention. It is sectional drawing which shows the 3rd basic composition of the organic EL element which concerns on embodiment of this invention. It is sectional drawing which represents roughly the structure of the film-forming apparatus used for manufacture of the organic EL element which concerns on embodiment. It is a flowchart showing the manufacture procedure of the organic EL element which concerns on embodiment. 1 is a schematic plan view of an organic EL device when an element substrate is viewed from a sealing substrate side. It is a block diagram which shows the whole structure of an organic electroluminescent apparatus. It is sectional drawing of the arbitrary pixel parts of the element substrate in which the data line, the scanning line, the anode, the light emitting layer, etc. were formed. It is sectional drawing which represents roughly the structure of the pixel part of the organic electroluminescent apparatus concerning 2nd Embodiment. It is a perspective view which shows the structure of the personal computer which is an example of the electronic device to which the organic EL apparatus is applied. It is a perspective view which shows the structure of the mobile telephone which is an example of the electronic device to which an organic EL apparatus is applied.

Explanation of symbols

1, 2, 3 ... Organic EL element, 10 ... Element substrate, 11a, 11b ... (metal) cathode, 20A, 20B ... Laminate, 21 ... (transparent) cathode, 22 ... Electron injection layer, 23 ... Organic layer, 24 ... Anode, 30 ... Transparent insulating layer, 50A, 50B ... Power source, 70 ... Pixel part, 74a, 74b ... Driving transistor, 200 ... Deposition device, 201 ... Vacuum deposition device, 202 ... Ion plating device, 203 ... Transport apparatus.

Claims (8)

It is laminated on one surface of the substrate, and at least one is composed of a pair of transparent electrode layers and an organic layer sandwiched between the pair of electrode layers (where n is a natural number of 2 or more) ) First laminate,
A first transparent insulating layer inserted between each of the n first stacked bodies;
It is laminated | stacked in the position facing the said 1st laminated body in the other surface of the said board | substrate, and at least one was comprised including a pair of transparent electrode layer and the organic layer pinched | interposed between this pair of electrode layer m (where m is a natural number of 2 or more) second laminates;
An organic EL element, comprising: a second transparent insulating layer inserted between each of the m second stacked bodies.   2. The organic EL according to claim 1, wherein the transparent electrode layer and the first and second transparent insulating layers in the first and second laminates are formed by an ion plating method, respectively. element. The electrode layer that is the uppermost layer on the one surface in the first stacked body, or the electrode layer that is the uppermost layer on the other surface in the second stacked body is made of a metal film,
3. The organic EL element according to claim 1, wherein electrode layers other than the metal film in the first and second laminates are made of a transparent conductive film.   4. Each of the first and second stacked bodies includes an electron injection layer for injecting electrons into the organic layer between the pair of electrode layers. 5. The organic EL element of description. An organic EL element according to any one of claims 1 to 4,
One end side is electrically connected to one of the pair of electrode layers in each of the first stacked bodies, and the other end side is electrically connected to a power source for driving each of the first stacked bodies. First power supply wiring
A first electrode wiring electrically connected to the other of the pair of electrode layers in each of the first stacked bodies;
One end side is electrically connected to one of the pair of electrode layers in each of the second stacked bodies, and the other end side is electrically connected to a power source for driving each of the second stacked bodies. Second power supply wiring
A second electrode wiring electrically connected to the other of the pair of electrode layers in each of the second laminates,
Each of the n first stacked bodies is electrically connected in parallel to the power supply by the first power supply wiring and the first electrode wiring, and the second power supply wiring and the second power supply wiring are connected. An organic EL device characterized in that each of the m second stacked bodies is electrically connected in parallel to the power supply by electrode wiring. It is laminated on one surface of the substrate, and at least one is composed of a pair of transparent electrode layers and an organic layer sandwiched between the pair of electrode layers (where n is a natural number of 2 or more) ), A first transparent insulating layer inserted between each of the n number of first laminates, and a layer opposite to the first laminate on the other surface of the substrate. And m (where m is a natural number of 2 or more) second laminated bodies, each including at least one pair of transparent electrode layers and an organic layer sandwiched between the pair of electrode layers, An organic EL element manufacturing method for manufacturing an organic EL element including a second transparent insulating layer inserted between each of m second stacked bodies,
Including a conductive layer forming step of forming a transparent electrode layer as at least one of the pair of electrode layers as a transparent conductive film by an ion plating method, and an organic layer forming step of forming the organic layer. Forming a body on said one surface and repeating n times,
A first insulating layer forming step of forming the first transparent insulating layer on the first stacked body by an ion plating method after the first stacking step;
Including a conductive layer forming step of forming a transparent electrode layer as at least one of the pair of electrode layers as a transparent conductive film by an ion plating method, and an organic layer forming step of forming the organic layer. Forming a body on the other surface and repeating m times,
And a second insulating layer forming step of forming the second transparent insulating layer on the second stacked body by an ion plating method after the second stacking step. At least a part of the steps is performed using a film forming apparatus in which a vacuum deposition apparatus and an ion plating apparatus are connected via a vacuum transfer chamber so that a sealed space can be formed together.
The method for manufacturing an organic EL element according to claim 6, wherein the conductive layer forming step and the first and second insulating layer forming steps are performed in the ion plating apparatus. When each of the first and second stacked bodies is formed between the pair of electrode layers so as to include an electron injection layer for injecting electrons into the organic layer,
The first and second lamination steps include
An electron injection layer forming step of forming the electron injection layer by a vacuum evaporation method in the vacuum evaporation apparatus;
A transfer step of transferring the substrate from the vacuum deposition apparatus to the ion plating apparatus through the vacuum transfer chamber after the electron injection layer formation step and before the conductive layer formation step. The manufacturing method of the organic EL element of Claim 7.

Images