JP6675931B2 - Substrate processing system, substrate processing method, and hole injection layer forming apparatus - Google Patents

Description

  The present invention relates to a substrate processing system, a substrate processing method, and a hole injection layer forming apparatus for forming an organic layer such as a hole injection layer of an organic light emitting diode on a substrate by a film forming method using an inkjet method.

  Conventionally, an organic light emitting diode (OLED) has been known as an organic EL (Electroluminescence) device. An organic EL display using such an organic light emitting diode has the advantages of being thin, lightweight, low power consumption, and excellent in response speed, viewing angle, and contrast ratio. In recent years, it has attracted attention as a panel display (FPD).

  The organic light emitting diode has a structure in which an organic layer is interposed between an anode and a cathode on a substrate. The organic layer includes, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer. When forming a hole injection layer or the like among these organic layers, a method of applying an organic material constituting the organic layer on a substrate by an inkjet method and forming a film is used.

  Among such organic light emitting diodes, those used for an organic EL display or the like have organic EL elements for each of red, green, and blue, and these elements have individual light emitting layers. As for the formation of these light-emitting layers, an ink-jet method can be adopted similarly to the above-described hole injection layer and the like, but the ink for the blue light-emitting layer is not practical in terms of emission luminance and the like. Therefore, in the conventional organic light emitting diode, the red light emitting layer and the green light emitting layer are formed by a film forming method using an inkjet method, and the blue light emitting layer is formed by a vapor deposition method (see Patent Document 1).

JP 2013-171771 A

  However, as disclosed in Patent Document 1, a hybrid type organic light emitting diode using both a film forming method using an ink jet method and a vapor deposition method has a long life of a blue organic EL element, specifically, a lighting life of blue light. There is room for improvement. Further, even if the lighting life of blue light can be extended by changing the method of manufacturing the organic light emitting diode, there is a problem if the emission characteristics of the red EL element and the green EL element are reduced. .

  The present invention has been made in view of the above circumstances, and a substrate processing system and a substrate processing method for forming an organic layer such as a hole injection layer of an organic light emitting diode on a substrate by a film forming method using an inkjet method. Another object of the present invention is to provide a hole injection layer forming apparatus that prolongs the lighting life of blue light while maintaining good emission characteristics of each color of an organic light emitting diode.

  In order to achieve the above object, the present invention provides a hole injection layer and a hole transport layer for each color of an organic light emitting diode that emits light in a color different from blue and blue, and a light emitting layer for the another color. A first hole injection layer forming apparatus for forming the hole injection layer for another color on a substrate at a first baking temperature, the substrate processing system being formed on the substrate; A hole transport layer forming apparatus for forming the hole transport layer for another color on the hole injection layer for another color at a second firing temperature higher than the first firing temperature; Forming a blue hole injection layer at a third firing temperature equal to or lower than the first firing temperature on the substrate on which the hole injection layer for one color and the hole transport layer for another color are formed. And a second hole injection layer forming apparatus to be formed.

  The substrate processing system may further include, on the hole transport layer for another color and the hole injection layer for blue formed on the substrate, at a firing temperature lower than the third firing temperature, A different layer forming apparatus for forming a light emitting layer and a hole transporting layer for blue respectively.

  In addition, the substrate processing system may include, in place of the heterogeneous layer forming apparatus, on the hole transport layer for another color formed on the substrate at a firing temperature lower than the third firing temperature, A light emitting layer forming apparatus for forming the light emitting layer, and the blue hole transport layer on the blue hole injection layer formed on the substrate at another firing temperature lower than the third firing temperature. May be provided with another apparatus for forming a hole transport layer.

  According to another aspect of the present invention, there is provided a hole injection layer forming apparatus for forming a blue hole injection layer on a substrate of an organic light emitting diode that emits light of a color different from blue and blue. And a discharge device for discharging an organic material constituting the hole injection layer for blue onto the substrate on which the hole injection layer and the hole transport layer of another color are formed.

  The hole injection layer forming apparatus includes a drying device for drying the organic material discharged onto the substrate by the discharge device, and a firing process for firing the organic material dried by the drying device to form the hole injection layer for blue. And a device.

  The apparatus for forming a hole injection layer further includes, when forming the hole injection layer for blue, a vaporized component of an organic material forming the hole injection layer for blue adheres to the hole transport layer of another color. It is preferable to have an anti-adhesion mechanism to prevent the adhesion.

  According to another aspect of the present invention, a hole injection layer and a hole transport layer for each color of an organic light emitting diode that emits light of a color different from blue and blue and a light emitting layer for the different color are formed on a substrate. Forming a hole injection layer for another color on a substrate at a first baking temperature, wherein the hole injection layer for another color is formed on the hole injection layer for another color formed on the substrate. Forming a hole transport layer for another color at a second firing temperature higher than the first firing temperature; and forming a hole injection layer for another color and a positive hole for another color. Forming a hole injection layer for blue at a third firing temperature equal to or lower than the first firing temperature on the substrate on which the hole transport layer is formed.

  The above-mentioned organic light-emitting diode is provided on the hole transport layer for another color, on the hole transport layer for another color, the light emitting layer for another color formed by a film forming method using an inkjet method, and on the hole transport layer for blue. And a blue light-emitting layer formed by an evaporation method so as to cover the light-emitting layer for another color.

  ADVANTAGE OF THE INVENTION According to this invention, the lighting life of blue light can be lengthened, maintaining the favorable light emission characteristic of each color in an organic light emitting diode.

FIG. 1 is a cross-sectional view schematically illustrating a configuration of an organic light emitting diode according to an embodiment of the present invention. FIG. 4 is a view for explaining a conventional method for forming an organic layer of an organic light emitting diode. FIG. 4 is a diagram for explaining a method of forming an organic layer of an organic light emitting diode by the substrate processing system according to the first embodiment of the present invention. It is a figure for explaining the example of composition of the substrate processing system concerning a 1st embodiment of the present invention. It is a figure explaining the example of composition of the substrate processing system concerning a 2nd embodiment of the present invention. It is a figure for explaining other examples of a below-mentioned 2nd hole injection layer formation device concerning the present invention.

  Hereinafter, embodiments of the present invention will be described. In the specification and the drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted.

  Since the embodiment of the present invention is a substrate processing system for forming an organic layer of an organic light emitting diode on a substrate by a film forming method using an ink jet method, the organic light emitting diode will be described first.

FIG. 1 is a sectional view schematically showing the configuration of an organic light emitting diode according to an embodiment of the present invention.
The organic light emitting diode 1 includes a red organic EL element 1R, a green organic EL element 1G, and a blue organic EL element 1B, and emits light of colors other than blue and blue (red and green).

  The red organic EL element 1R emits red light, and on a glass substrate (hereinafter abbreviated as substrate) 10 as a substrate, an anode (anode) 11R, a hole injection layer 12R, It has a configuration in which a hole transport layer 13R, a red light emitting layer 14R, a connection layer (Hybrid Connection Layer) 15, a blue light emitting layer 16, an electron transport layer 17, an electron injection layer 18, and a cathode (cathode) 19 are stacked.

  The green organic EL element 1G emits green light, and similarly to the red organic EL element 1R, an anode 11G, a hole injection layer 12G, and a hole transport layer 13G are formed on the substrate 10 in this order from the substrate 10 side. , A green light-emitting layer 14 </ b> G, a connection layer 15, a blue light-emitting layer 16, an electron transport layer 17, an electron injection layer 18, and a cathode 19.

  The blue organic EL element 1B emits blue light. On the substrate 10, an anode 11B, a hole injection layer 12B, a hole transport layer 13B, a connection layer 15, a blue light emitting layer 16 are arranged in this order from the substrate G side. , An electron transport layer 17, an electron injection layer 18, and a cathode 19.

  Although not shown, a drive circuit for driving each of the elements 1R, 1G, and 1B and a partition wall for the purpose of insulating the elements from each other are provided on the substrate G. In the following description, in the organic light emitting diode 1, the portions on the anodes 11R, 11G, and 11B sides are described as lower portions, and the portions on the cathode 19 side are described as upper portions.

  The anodes 11R, 11G, and 11B are transparent electrodes made of, for example, ITO (Indium Tin Oxide), and are formed by an evaporation method or the like.

  The hole injection layers 12R, 12G, and 12B are layers for improving hole injection efficiency, and are formed by a film forming method using an inkjet method. The same material is used for the hole injection layers 12R, 12G, and 12B.

  Note that in a film formation method using an ink-jet method, an organic material for the hole injection layers 12R, 12G, and 12B is applied, and then the organic material is dried and fired at a predetermined firing temperature, so that the hole is injected. The injection layers 12R, 12G, and 12B are formed. The same applies to the case where a film formation method using an inkjet method is adopted for other layers (for example, the hole transport layers 13R, 13G, and 13B).

  The hole transport layers 13R and 13G of the red organic EL element 1R and the green organic EL element 1G are layers for increasing the efficiency of transporting holes to the red light emitting layer 14R and the green light emitting layer 14G, respectively, and the blue organic EL element 1B The hole transport layer 13B is a layer for increasing the efficiency of transporting holes to the blue light emitting layer 16.

The same material is used for the hole transport layers 13R and 13G of the red organic EL element 1R and the green organic EL element 1G.
For the hole transport layer 13B of the blue organic EL element 1B, the material of the hole transport layer 13R of the red organic EL element 1R and the material of the hole transport layer 13G of the green organic EL element 1G are determined from the relationship of blue light emission efficiency and the like. Different materials are used.
The hole transport layers 13R, 13G, and 13B are formed by a film forming method using an inkjet method.

  Since the molecular design for increasing the hole transport efficiency and the molecular design for increasing the hole injection efficiency are different, each of the hole injection layer 12R and the hole transport layer 13R of the red organic EL element 1R has a different structure. Is different, and the firing temperature suitable for the organic material of the hole transport layer 13R is higher than the firing temperature suitable for the organic material of the hole injection layer 12R. The same applies to the green organic EL element 1G.

  The red light emitting layer 14R and the green light emitting layer 14G are layers that generate red and green light by recombination of electrons and holes in the layers 14R and 14G, respectively. The red light emitting layer 14R and the green light emitting layer 14G are formed by a film forming method using an inkjet method.

  The connection layer 15 is a layer that prevents holes that have not been recombined in the red light emitting layer 14R and the green light emitting layer 14G from reaching the blue light emitting layer 16, and is formed over the entire surface of the substrate 10. Are formed so as to cover the red light emitting layer 14R, the green light emitting layer, and the hole transport layer 13B. This connection layer 15 is formed by, for example, an evaporation method.

  The blue light emitting layer 16 is a layer that emits blue light by recombining electrons and holes in the layer 16. The blue light emitting layer 16 is also formed over the entire surface of the substrate 10 in the same manner as the connection layer 15. Specifically, not only the upper part of the hole transport layer 13B of the blue organic EL element 1B but also the red light emitting layer 14R and the green It is formed so as to cover also the upper part of the light emitting layer 14G. The blue light emitting layer 16 is formed by, for example, an evaporation method.

The electron transport layer 17 is a layer for increasing the efficiency of transporting electrons to the red light emitting layer 14R, the green light emitting layer 14G, and the blue light emitting layer 16.
The electron injection layer 18 is a layer for improving electron injection efficiency.
For the cathode 19, for example, aluminum is used.
The electron transport layer 17, the electron injection layer 18, and the cathode 19 are formed by, for example, an evaporation method.

  Among the layers constituting the organic light emitting diode 1, the hole injection layers 12R, 12G, 12B, the hole transport layers 13R, 13G, 13B, the red light emitting layer 14R, the green light emitting layer 14G, the connection layer 15, the blue light emitting layer 16, The electron transport layer 17 and the electron injection layer 18 are organic layers made of an organic material. In addition, among these organic layers, the hole injection layers 12R, 12G, and 12B, the hole transport layers 13R, 13G, and 13B, the red light-emitting layer 14R, and the green light-emitting layer 14G are formed by the inkjet method as described above. It is formed.

  The organic light-emitting diode 1 having the above-described components is configured such that a predetermined number of holes injected in the hole injection layer 12R are applied to the red organic EL element 1R by applying a voltage between the anode 11R and the cathode 19 of the red organic EL element 1R. A predetermined number of electrons transported to the red light emitting layer 14R via the transport layer 13R and injected by the electron injection layer 18 are transferred to the red light emitting layer 14R via the electron transport layer 17, the blue light emitting layer 16 and the connection layer 15. Be transported. Then, holes and electrons are recombined in the red light emitting layer 14R to form excited state molecules, and the light emitting layer 14R emits light. The same applies to the green organic EL element 1G.

  On the other hand, by applying a voltage between the anode 11B and the cathode 19 of the blue organic EL element 1B, a predetermined amount of holes injected in the hole injection layer 12B is transmitted through the hole transport layer 13B and the connection layer 15. Then, a predetermined number of electrons injected by the electron injection layer 18 are transported to the blue light emitting layer 16 via the electron transport layer 17. Then, holes and electrons are recombined in the blue light emitting layer 16 to form excited molecules, and the light emitting layer 16 emits light.

In such an organic light emitting diode, the emission life of blue light is short. In this regard, as a result of repeated studies by the present inventors, it has been found that the lower the firing temperature of the hole injection layer of the blue organic EL device, the longer the emission life of blue light.
It was also found that when the firing temperature of the hole injection layer of each color was lowered, the hole injection efficiency was increased, that is, the amount of current was increased. Further, regarding the red organic EL element and the green organic EL element, when the firing temperature of the hole injection layer is lowered, the light emission characteristics of these elements are deteriorated. It was clarified that the blue component increased in the light.
In other words, the material of the hole injection layer of the organic light emitting diode according to the present embodiment is a material that, when the firing temperature is low, has a longer light emission lifetime of blue light and lowers the light emission characteristics of the red and green organic EL elements. It became clear that it was.

  The following can be considered as a reason why the emission temperature of the red organic EL element is deteriorated when the firing temperature of the hole injection layer is lowered. By lowering the firing temperature of the hole injection layer, the hole injection efficiency is increased, that is, the amount of holes is increased, and even if the connection layer 15 is present, only the red light emitting layer of the red organic EL element is used. It is considered that recombination of holes and electrons occurs in the blue light emitting layer, and blue light is emitted. The same reason can be considered for the emission characteristics of the green organic EL element.

Based on these findings, the present inventor has conceived of a substrate processing system that can extend the life of a blue organic EL element without deteriorating the emission characteristics of the red organic EL element and the green organic EL element.
Before describing a method for forming an organic layer according to the first embodiment of the present invention, a conventional method for forming an organic layer of an organic light emitting diode will be described.

FIG. 2 is a view for explaining a conventional method for forming an organic layer of the organic light emitting diode 1.
In the conventional method for forming an organic layer of the organic light emitting diode 1, first, as shown in FIG. 2A, anodes 11R, 11G of a red organic EL element 1R, a green organic EL element 1G, and a blue organic EL element 1B, respectively. , 11B, the hole injection layers 12R, 12G, 12B are formed by a film forming method using an inkjet method. Specifically, an organic material for the hole injection layers 12R, 12G, and 12B is applied on each of the anodes 11R, 11G, and 11B by an ink-jet method, and then the organic material is dried and heated at a predetermined firing temperature (for example, 150 ° C.). ) To form the hole injection layers 12R, 12G, and 12B.

  Next, as shown in FIG. 2B, a hole transport layer 13R is formed on the hole injection layer 12R of the red organic EL element 1R, and a hole transport layer 13G is formed on the hole injection layer 12G of the green organic EL element 1G. Are each formed by a film forming method using an ink jet method. Specifically, the organic materials of the hole transport layers 13R and 13G are applied on the hole injection layers 12R and 12G of the red organic EL element 1R and the green organic EL element 1G by an ink jet method, and thereafter, the organic material is applied. It is dried and fired at a firing temperature (for example, 200 ° C.) higher than a predetermined firing temperature of the hole injection layers 12R, 12G, and 12B to form the hole transport layers 13R, 13G.

In this conventional method, after simultaneously forming the hole injection layers 12R, 12G, and 12B, that is, after forming the hole injection layer 12B of the blue organic EL element 1B, the firing temperature is higher than that at the time of forming the hole injection layer. The formation of the hole transport layers 13R and 13B accompanied by baking is performed. Therefore, even if the firing temperature of the entire hole injection layer including the hole injection layer 12B is lowered for the purpose of extending the life of the blue organic EL element 1B, a desired result cannot be obtained.
Therefore, in the substrate processing system according to the first embodiment of the present invention, the organic layer of the organic light emitting diode 1 is formed as follows.

FIG. 3 is a diagram illustrating a method for forming an organic layer of the organic light emitting diode according to the first embodiment.
In the present forming method, as shown in FIG. 3A, a hole injection layer 12R, 12G is formed on each of the anodes 11R, 11G of the red organic EL element 1R and the green organic EL element 1G by an inkjet method. Formed. Specifically, an organic material for the hole injection layers 12R and 12G is applied on each of the anodes 11R and 11G by an inkjet method, and then the organic material is dried and fired at a first firing temperature (for example, 150 ° C.). Then, the hole injection layers 12R and 12G are formed.

  Next, as shown in FIG. 3B, a hole transport layer 13R is formed on the hole injection layer 12R of the red organic EL element 1R, and a hole transport layer 13G is formed on the hole injection layer 12G of the green organic EL element 1G. Are formed by a film forming method using an ink jet method. Specifically, the organic materials of the hole transport layers 13R and 13G are applied on the hole injection layers 12R and 12G of the red organic EL element 1R and the green organic EL element 1G by an ink jet method, and thereafter, the organic material is applied. It is dried and fired at a second firing temperature (for example, 200 ° C.) higher than the first firing temperature to form the hole transport layers 13R and 13G.

  Thereafter, as shown in FIG. 3C, a hole injection layer 12B is formed on the anode 11B of the blue organic EL element 1B by a film forming method using an inkjet method. Specifically, an organic material for the hole injection layer 12B is applied on the anode 11B by an inkjet method, and then the organic material is dried and fired at a third firing temperature equal to the first firing temperature. The hole injection layer 12B is formed.

  Then, as shown in FIG. 3D, a red light emitting layer 14R is formed on the hole transport layer 13R of the red organic EL element 1R, a green light emitting layer 14G is formed on the hole transport layer 13G of the green organic EL element 1G, A hole transport layer 13B is formed on the hole injection layer 12B of the blue organic EL element 1B by a film forming method using an inkjet method. Specifically, the organic material of the red light emitting layer 14R is formed on the hole transport layer 13R, the organic material of the green light emitting layer 14G is formed on the hole transport layer 13G, and the organic material of the hole transport layer 13B is formed on the hole injection layer 12B. Organic materials are applied by an ink-jet method, and these organic materials are dried and fired at a firing temperature lower than the first firing temperature (for example, 100 ° C.), and the red light emitting layer 14R, the green light emitting layer 14G, and the hole transport layer 13B are formed. To form

  After the film formation by the inkjet method, the connection layer 15, the blue light emitting layer 16, and the like are formed by a vapor deposition method.

  As described above, in the method of forming the organic layer of the organic light emitting diode 1 in the substrate processing system according to the present embodiment, the hole injection layer 12B of the blue organic EL element 1B is replaced with the red organic EL element 1R and the green organic EL element 1G. Instead of being formed simultaneously with the hole injection layers 12R and 12G, they are formed after the formation of the hole transport layers 13R and 13G that require a high temperature. Accordingly, since the hole injection layer 12B of the blue organic EL element 1B is not exposed to a high temperature, the lighting life of the organic light emitting diode 1 for blue light can be extended as compared with that manufactured by a conventional method. . In addition, since the hole injection layers 12R and 12G and the hole transport layers 13R and 13G of the red organic EL element 1R and the green organic EL element 1G are fired at the same firing temperature as the conventional one, the red and green light emission characteristics are the same. There is no deterioration as compared with those manufactured by the method.

In order to perform the method for forming the organic layer of the organic light emitting diode 1 described above, the substrate processing system according to the present embodiment is configured as follows.
FIG. 4 is a diagram illustrating a configuration example of the substrate processing system according to the present embodiment. The anodes 11R, 11G, and 11B are previously formed on the substrate 10 to be processed by the substrate processing system 100 in FIG. 4, and the substrate processing system 100 includes the hole injection layers 12R, 12G, and 12B, The transport layers 13R, 13G, 13B, the red light emitting layer 14R, and the green light emitting layer 14G are formed.

  The substrate processing system 100 of FIG. 4 includes a first hole injection layer forming device 110, a hole transport layer forming device 120, a second hole injection layer forming device 130, and a heterogeneous layer forming device 140. They are arranged side by side in this order along the transport path 101 of the substrate 10.

  The first hole injection layer forming apparatus 110 forms the hole injection layer 12R of the red organic EL element 1R and the hole injection layer 12G of the green organic EL element 1G on the substrate 10 at a first firing temperature. is there.

  The first hole injection layer forming apparatus 110 applies the organic material of the hole injection layers 12R and 12G to the anodes 11R and 11G of the red organic EL element 1R and the green organic EL element 1G on the substrate 10 by an ink jet method. An ink jet type coating device (hereinafter, IJ device) 111 is provided as a discharge device.

  In addition, the first hole injection layer forming apparatus 110 includes a dryer 112 for drying the organic material applied by the IJ apparatus 111 under reduced pressure. The dryer 112 has, for example, a turbo-molecular pump (not shown), and is configured to dry the organic material by reducing the internal atmosphere to, for example, 1 Pa or less by the turbo-molecular pump.

  Further, the first hole injection layer forming apparatus 110 includes a baking machine 113 for baking the organic material dried by the drier 112 at a first baking temperature. The baking machine 113 has a hot plate (not shown) on which the substrate 10 is placed, and is configured to bake the organic material by the hot plate.

  The organic material applied by the IJ apparatus 111 is dried by the dryer 112 and fired at the first firing temperature by the firing machine 113, so that the hole injection layers 12R and 12G are formed on the substrate (the anodes 11R and 11G). It is formed.

  Although not shown, the first hole injection layer forming device 110 includes a substrate transport device that transports the substrate 10 to the IJ device 111, the dryer 112, and the baking machine 113, and a transition for transferring the substrate 10. The apparatus includes a device, a buffer device for temporarily storing the substrate 10, a temperature adjusting device for adjusting the substrate fired by the firing machine 113 to a predetermined temperature (for example, normal temperature), and the like. These substrate transfer device, transition device, buffer device, and temperature control device are also provided in the hole transport layer forming device 120, the second hole injection layer forming device 130, and the heterogeneous layer forming device 140.

  The hole transport layer forming apparatus 120 forms the hole transport layer 13R and the hole transport layer 13G at the second firing temperature on the hole injection layer 12R and the hole injection layer 12G formed on the substrate 10, respectively. Things.

  The hole transport layer forming apparatus 120 includes an IJ apparatus 121 that applies the organic materials of the hole transport layers 13R and 13G to the hole injection layers 12R and 12G of the substrate 10 by an inkjet method.

  In addition, the hole transport layer forming device 120 includes a dryer 122 for drying the organic material applied by the IJ device 121 under reduced pressure. The configuration of the dryer 122 is the same as that of the dryer 112 described above.

  Further, the hole transport layer forming device 120 includes a firing machine 123 for firing the organic material dried by the dryer 122 at a second firing temperature. The configuration of the baking machine 123 is the same as that of the baking machine 113 described above.

  The organic material applied by the IJ apparatus 121 is dried by the dryer 122 and fired by the firing machine 123 at the second firing temperature, so that the hole transport layers 13R and 13G (the hole injection layers 12R and 12G of the substrate) are formed. ).

  The second hole injection layer forming apparatus 130 forms the third hole injection layer 12B of the blue organic EL element 1B on the substrate 10 on which the hole injection layers 12R and 12G and the hole transport layers 13R and 13G are formed. It is formed at the firing temperature.

  The second hole injection layer forming apparatus 130 is provided on the anode 11B of the substrate 10 on which the hole injection layers 12R and 12G and the hole transport layers 13R and 13G of the red organic EL element 1R and the green organic EL element 1G are formed. And an IJ apparatus 131 for applying the organic material of the hole injection layer 12B by an ink jet method.

  Further, the second hole injection layer forming apparatus 130 has a dryer 132 for drying the organic material applied by the IJ apparatus 131 under reduced pressure. The configuration of the dryer 132 is the same as that of the dryer 112 described above.

  Further, the second hole injection layer forming apparatus 130 has a firing machine 133 for firing the organic material dried by the dryer 132 at a third firing temperature. The configuration of the baking machine 133 is the same as that of the baking machine 113 described above.

  The organic material applied by the IJ device 131 is dried by the dryer 132 and fired at the third firing temperature by the firing machine 133, so that the hole injection layer 12B is formed on (the anode 11B of) the substrate.

  The different layer forming apparatus 140 includes a red light emitting layer 14R on the hole transport layer 13R, a green light emitting layer 14G on the hole transport layer 13G, a hole transport layer 13B on the hole injection layer 12B, and a fourth layer. It is formed at each firing temperature.

  The heterogeneous layer forming apparatus 140 includes an organic material for the red light emitting layer 14R on the hole transport layer 13R, an organic material for the green light emitting layer 14G on the hole transport layer 13G, and a hole transport on the hole injection layer 12B. An IJ device 141 for applying the organic material of the layer 13B by an ink-jet method is provided. Since the organic material of the red light emitting layer 14R, the organic material of the green light emitting layer 14G, and the organic material of the hole transport layer 13B are different materials, the IJ device 141 has a droplet discharge head (nozzle) for each organic material.

  The heterogeneous layer forming apparatus 140 has a dryer 142 for drying the organic material applied by the IJ apparatus 141 under reduced pressure. The configuration of the dryer 142 is the same as that of the dryer 112 described above.

  Further, the heterogeneous layer forming apparatus 140 has a firing machine 133 for firing the organic material dried by the dryer 142 at a fourth firing temperature. The configuration of the baking machine 133 is the same as that of the baking machine 113 described above.

  The plurality of organic materials applied by the IJ device 141 are collectively dried by the dryer 142 and baked collectively by the baking machine 133 at the fourth baking temperature, so that the red light emitting layer 14R, the green light emitting layer 14G and The hole transport layer 13B is formed on the substrate (the hole transport layers 13R and 13G and the hole injection layer 12B).

  The above-described substrate processing system 100 has a control unit (not shown). Each device 110, 120, 130, 140 of the substrate processing system 100 is controlled by this control unit.

  In the substrate processing system 100, as described above, the second hole injection layer 12B is formed separately from the first hole injection layer forming apparatus 110 that forms the hole injection layers 12R and 12G. The forming apparatus 130 is provided, and after forming the hole transport layers 13R and 13G requiring high temperature, the hole injection layer 12B is formed by the second hole injection layer forming apparatus 130. Accordingly, since the hole injection layer 12B is not exposed to a high temperature, the lighting life of the organic light emitting diode 1 for blue light can be extended as compared with that manufactured by the conventional method. Further, since the hole injection layers 12R and 12G and the hole transport layers 13R and 13G are fired at the same firing temperature as before, the red and green emission characteristics may be deteriorated as compared with those manufactured by the conventional method. Absent.

  In the above description, the third baking temperature, that is, the baking temperature of the hole injection layer 12B of the blue organic EL element 1B is the first baking temperature, that is, the baking temperature of the red organic EL element 1R and the green organic EL element 1G. Although described as being the same, the third firing temperature may be lower than the first firing temperature. Thereby, the lighting life of the blue light of the organic light emitting diode 1 can be further extended.

FIG. 5 is a diagram illustrating a substrate processing system according to a second embodiment of the present invention.
In the substrate processing system 100 of FIG. 4, the red light emitting layer 14R, the green light emitting layer 14G, and the hole injection layer 12B of the blue organic EL element 1B are fired at the same firing temperature (fourth firing temperature). The apparatus, that is, the heterogeneous layer forming apparatus 140 was used.

In contrast, the substrate processing system 200 of FIG. 5 includes a device for forming the red light emitting layer 14R and the green light emitting layer 14G (light emitting layer forming device 210) and a device for forming the hole transport layer 13B (hole transport layer forming device). 220) are separate devices.
This configuration includes the firing temperature of the firing device 213 of the light emitting layer forming device 210, that is, the firing temperature of the red light emitting layer 14R and the green light emitting layer 14G, and the firing temperature of the firing device 213 of the hole transport layer forming device 220, that is, the hole. It is preferable when the firing temperature of the injection layer 12B is different. These firing temperatures are designed so that the above-described third firing temperature is lower.

  The configurations of the IJ devices 211 and 221 and the dryers 212 and 222 of the light emitting layer forming device 210 and the hole transport layer forming device 220 are the same as those of the heterogeneous layer forming device 140.

  In addition, the firing temperature of the red light emitting layer 14R and the firing temperature of the green light emitting layer 14G may be different. In this case, the apparatus for forming the red light emitting layer 14R and the apparatus for forming the green light emitting layer 14G are separate. Preferably, it is a device.

FIG. 6 is a schematic diagram illustrating another example of the second hole injection layer forming apparatus.
The second hole injection layer forming apparatus 130 'of FIG. 6 has an adhesion preventing mechanism 134 in a dryer 132'.

  When the hole injection layer 12B of the blue organic EL element 1B is formed, the adhesion preventing mechanism 134 converts the vaporized component of the organic material of the hole injection layer 12B into the hole transport layer 13R and / or the blue color of the red organic EL element 1R. This is to prevent adhesion to the hole transport layer 13B of the organic EL element 1B. The adhesion preventing mechanism 134 can be constituted by, for example, a cooling plate. The cooling plate is a plate-like member cooled to a lower temperature than the substrate 10 on which the hole transport layers 13R and 13B are formed, and is separated from the substrate 10 placed in the device (dryer 132 '). It is provided at the position.

  Further, the adhesion preventing mechanism 134 can be configured by a heating device that heats the substrate 10 on which the hole transport layers 13R and 13B are formed. Further, the adhesion preventing mechanism 134 can be constituted by the cooling plate and the heating device.

  In the above example, the adhesion preventing mechanism is provided in the dryer of the second hole injection layer forming apparatus, but may be provided in the IJ apparatus or the baking machine. It may be provided on two or all of them.

  INDUSTRIAL APPLICATION This invention is useful for the technique of apply | coating a processing liquid on a board | substrate.

100, 200: substrate processing system 110: first hole injection layer forming device 111, 121, 131, 141, 211, 221: ink jet type coating device (IJ device)
112, 122, 132, 132 ', 142, 212, 222 ... dryer 113, 123, 133, 143, 213, 223 ... baking machine 120 ... hole transport layer forming apparatus 130, 130' ... second hole injection Layer forming device 134: adhesion preventing mechanism 140: heterogeneous layer forming device 210: light emitting layer forming device 220: hole transport layer forming device

Claims (9)

A substrate processing system for forming a hole injection layer and a hole transport layer for each color of the organic light emitting diode that emits light of a different color from blue and blue and the light emitting layer for the different color on a substrate,
A first hole injection layer forming apparatus for forming the hole injection layer for another color on a substrate at a first baking temperature;
A hole transport layer that forms the hole transport layer for another color on the hole injection layer for another color formed on the substrate at a second firing temperature higher than the first firing temperature; A forming device;
At a third firing temperature equal to or lower than the first firing temperature, blue hole injection is performed on the substrate on which the hole injection layer for another color and the hole transport layer for another color are formed. A second hole injection layer forming apparatus for forming a layer.   On the hole transport layer for another color and the hole injection layer for blue formed on the substrate, at a firing temperature lower than the third firing temperature, the light emitting layer for another color and the blue The substrate processing system according to claim 1, further comprising a different layer forming apparatus that forms each of the hole transport layers. A light emitting layer forming apparatus for forming the light emitting layer for another color on the hole transporting layer for another color formed on the substrate at a firing temperature lower than the third firing temperature;
Another hole transport layer forming apparatus for forming the hole transport layer for blue at another firing temperature lower than the third firing temperature on the hole injection layer for blue formed on the substrate. The substrate processing system according to claim 1, further comprising:   The organic light emitting diode, on the hole transport layer for another color, the light emitting layer for another color formed by a film forming method using an inkjet method, and on the hole transport layer for blue The substrate processing system according to any one of claims 1 to 3, further comprising a blue light emitting layer formed by a vapor deposition method so as to cover the light emitting layer for another color. A hole injection layer forming apparatus for forming a hole injection layer for blue of an organic light emitting diode that emits light of a different color from blue and blue on a substrate,
On the substrate on which the hole injection layer of another color and the hole transport layer of another color are formed, a discharge device for discharging an organic material constituting a hole injection layer for blue to the substrate is provided. A hole injection layer forming apparatus characterized by the above-mentioned. A drying device for drying the organic material discharged to the substrate by the discharge device,
The hole injection layer forming apparatus according to claim 5, further comprising: a firing apparatus for firing the organic material dried by the drying apparatus to form the hole injection layer for blue.   At the time of forming the hole injection layer for blue, having an adhesion preventing mechanism for preventing a vaporized component of an organic material constituting the hole injection layer for blue from being attached to the hole transport layer of another color. The hole injection layer forming apparatus according to claim 5, wherein:   The organic light emitting diode, on the hole transport layer for another color, the light emitting layer for another color formed by a film forming method using an inkjet method, and on the hole transport layer for blue The hole injection layer according to any one of claims 5 to 7, further comprising a blue light-emitting layer formed by an evaporation method so as to cover the light-emitting layer for another color. Forming equipment. A substrate processing method of forming a hole injection layer and a hole transport layer for each color of the organic light emitting diode that emits light of a different color from blue and blue and a light emitting layer for the different color on a substrate,
Forming the hole injection layer for another color on a substrate at a first baking temperature;
Forming the hole transport layer for another color at a second firing temperature higher than the first firing temperature on the hole injection layer for another color formed on the substrate;
At a third firing temperature equal to or lower than the first firing temperature, the blue hole injection is performed on the substrate on which the hole injection layer for another color and the hole transport layer for another color are formed. Forming a layer.