CN100490213C - Method of manufacturing color filter substrate, method of manufacturing electro-optical device, electro-optical device, and electronic apparatus - Google Patents

Abstract

The invention provides a method of manufacturing an electro-optical device, which is characterized in that it includes the steps of forming a first partition wall part (112a) and a second partition wall part (112b) on a substrate, and spraying each partition wall part by a droplet ejection method. A step of ejecting a liquid containing each functional material constituting the electro-optical layer from each opening. The ejected liquid has different viscosities for the respective electro-optic layers. On the other hand, in the partition wall forming step, at the position where the viscosity is ejected relatively low, the liquid from the first partition wall (112a) 2 The surface area of the protruding part of the partition wall part (112b) is relatively small, and at the position where a relatively high-viscosity liquid is ejected, the part of the first partition wall part (112a) protrudes from the second partition wall part (112b) The surface area of the part is relatively large. Thereby, the film thickness uniformity and flatness of the formed electro-optic layer can be improved.

Description

Manufacturing method of color filter substrate, electro-optical device and manufacturing method thereof, electronic device

technical field

The present invention relates to a manufacturing method of a color filter substrate, a manufacturing method of an electro-optical device, an electro-optical device, and an electronic device.

Background technique

In recent years, the development of color organic electroluminescent devices (organic EL devices) having a structure using an inkjet method that liquefies light-emitting material inks such as organic fluorescent materials and ejects the ink onto a substrate is ongoing. , a method of patterning a luminescent material, in which a luminescent layer made of the luminescent material is sandwiched between an anode and a cathode (for example, refer to Patent Document 1).

[Patent Document 1] JP-A-2002-252083

However, in the case of using the inkjet method to manufacture an organic EL device, it is important to uniformize the emission characteristics (luminance, color purity, etc.) of each pixel (light-emitting element) formed in an array. The utilization rate of manufacturing materials has a great influence. When uniformizing the above-mentioned luminescent characteristics, it is necessary to form each luminescent layer uniformly and flatly among the pixels, and in particular, the uniformity and flatness of the film thickness are greatly affected by the drying conditions of the applied ink. Therefore, the drying condition becomes a very important factor for improving the uniformity of the light-emitting element. In the aforementioned Patent Document 1, although there is no clear description of the drying step of the ink dripped on the substrate, the formation of the light emitting layer is actually performed through the following steps.

First, a substrate on which pixel electrodes and banks for dividing each pixel region are formed is prepared, and a hole injection/transport layer is first formed in the region surrounded by the bank by an inkjet method. Thereafter, on the substrate on which the hole injection/transport layer was formed, the ink for the red light-emitting layer filled in the inkjet head was dropped into the region surrounded by the banks, and then the dropped ink was dried to obtain A red luminescent layer is formed. Similarly, the ink for the green light-emitting layer was fixedly placed on the substrate using an inkjet head, and the green light-emitting layer was formed through a drying process. Next, the ink for the blue light-emitting layer was fixedly arranged on the substrate using an inkjet head in the same manner, followed by a drying process to form a blue light-emitting layer. In this way, a color organic EL device is produced by patterning the red light-emitting layer, the green light-emitting layer, and the blue light-emitting layer on the substrate.

In this way, when forming light-emitting layers with different light-emitting colors, a manufacturing method is generally employed in which ink of one color is dropped, dried, and then light-emitting layers of other colors are formed. This is because, generally, in light-emitting layers with different light-emitting colors, ink constituent materials are different, and thus the composition of the solvent is also different, and thus the optimal conditions for dropping and drying are different for each color.

However, since the ink is sequentially dripped and dried for each color in this way, it takes a lot of time to manufacture, and, for example, after the red light emitting layer is formed, in the process of forming the green light emitting layer, the The dried red light-emitting layer is exposed again to a solvent atmosphere, and the red light-emitting layer may be re-dissolved depending on the type of solvent. As a result, deterioration may occur in the light-emitting layer, resulting in deterioration of characteristics.

Contents of the invention

The present invention was made to solve the above-mentioned problems, and an object of the present invention is to provide a color filter substrate that can greatly improve the production efficiency of a color filter substrate having a plurality of colored layers, and can make the film thickness of each colored layer formed uniform. And a method of manufacturing a color filter substrate with improved flatness. In addition, it is also an object to provide an electro-optical device that can greatly improve the production efficiency of an electro-optical device including a plurality of electro-optical layers such as a light-emitting layer, and that can improve the film thickness uniformity and flatness of each formed electro-optical layer. A method of manufacturing an electro-optical device.

In order to solve the above-mentioned problems, the method for manufacturing a color filter substrate of the present invention is a method for manufacturing a color filter substrate provided with a plurality of multicolor colored layers in a predetermined pattern, and is characterized in that it includes: forming a first partition wall portion on the substrate and the second partition wall part forming step, wherein the first partition wall part has a first opening part constituting the formation region of the colored layer, the second partition wall part is located on the first partition wall part, and has the same configuration of the colored layer. the second opening in the layer forming region; and spraying a liquid in which each coloring material constituting the coloring layer is dissolved or dispersed in a solvent into each opening of each of the partition walls by a droplet discharge method The ejecting step of the above, wherein the ejected liquid is a liquid having a different viscosity for each colored layer, and in the partition forming step, the ejected liquid is in a shape protruding from the inner surface of the opening of the second partition The first partition wall portion is formed such that the surface area of a portion protruding from the second partition wall portion among the first partition wall portion is relatively small in the opening portion from which a relatively low-viscosity liquid is ejected, and on the other hand, In the opening from which the relatively high-viscosity liquid is ejected, the surface area of a portion protruding from the second partition among the first partitions is made relatively large.

As a result of repeated studies by the present inventors in view of the above problems, it was found that the film thickness of the formed colored layer becomes non-uniform due to the difference in viscosity of the liquid. That is, when the viscosity of the liquid used is high, the film thickness of the colored layer formed in the opening of the partition wall tends to increase at the center; The film thickness of the colored layer in the opening of the portion tends to become larger at the peripheral portion (the side closer to the partition wall portion).

In addition, as a result of research by the present inventors, it has been found that the film thickness of the formed colored layer becomes non-uniform due to the difference in surface area of the portion (protruding portion) protruding from the inner surface of the opening of the second partition wall portion among the first partition wall portion. That is, when the surface area of the above-mentioned protruding portion of the first partition wall portion is small, the film thickness of the colored layer formed in the opening of the partition wall portion tends to become larger at the central portion; When the surface area of the protruding portion is large, the film thickness of the colored layer formed in the opening of the partition wall portion tends to increase at the peripheral portion (the side closer to the partition wall portion).

Furthermore, based on such research results, the present inventors succeeded in discovering a method that can make the film thickness of the colored layer uniform and flat when the viscosity of the liquid used varies for each pattern. That is, by appropriately adjusting the area of the protruding portion of the first partition wall according to the viscosity of the liquid as in the above-mentioned production method of the present invention, specifically, by ejecting a relatively low-viscosity liquid In the opening portion of the first partition wall portion, the surface area of the protruding portion of the first partition wall portion is relatively small, and in the opening portion for ejecting a relatively high-viscosity liquid, the surface area of the protruding portion of the first partition wall portion is relatively large, The film thickness of each colored layer can be made uniform and flat.

In addition, in order to solve the above-mentioned problems, the method for manufacturing an electro-optical device of the present invention is a method for manufacturing an electro-optical device having a plurality of various types of electro-optical layers in a predetermined pattern, and is characterized by comprising: forming a first partition wall on a substrate part and the second partition wall part forming process, wherein the first partition wall part has the first opening part constituting the formation region of the electro-optical layer, the second partition wall part is located on the first partition wall part, and also has the configuration the second opening in the region where the electro-optical layer is formed; and each function of the electro-optical layer that is dissolved or dispersed in a solvent is discharged into each opening of each of the partition walls by a droplet discharge method. A step of ejecting a liquid material of a material, wherein the ejected liquid is a liquid having a different viscosity for each electro-optic layer, and in the step of forming the partition wall, the second partition wall The inner surface of the opening of the opening protrudes to form the first partition wall, and the surface area of the part protruding from the second partition wall of the first partition wall is relatively small in the opening for ejecting a relatively low-viscosity liquid. On the other hand, the surface area of the part protruding from the second partition wall among the first partition wall parts is made relatively large in the opening part from which a relatively high-viscosity liquid is ejected.

As a result of repeated studies by the present inventors in view of the above problems, it was found that the film thickness of the formed electro-optical layer becomes non-uniform due to the difference in viscosity of the liquid. That is, when the viscosity of the liquid used is high, the film thickness of the electro-optical layer formed in the opening of the partition portion tends to become larger at the center; The film thickness of the electro-optic layer in the opening of the partition wall tends to increase at the peripheral portion (the side closer to the partition wall).

In addition, as a result of research by the present inventors, it has been found that the film thickness of the formed electro-optic layer becomes non-uniform due to the difference in surface area of the portion (protruding portion) protruding from the inner surface of the opening of the second partition wall portion among the first partition wall portion. . That is, when the surface area of the protrusion of the first partition wall is small, the film thickness of the electro-optical layer formed in the opening of the partition wall tends to become larger at the center. On the other hand, when the surface area of the first partition wall When the surface area of the protruding portion is large, the film thickness of the electro-optical layer formed in the opening of the partition wall tends to increase at the peripheral portion (the side closer to the partition wall).

Furthermore, based on such research results, the present inventors succeeded in discovering a method for making the film thickness of the electro-optic layer uniform and flat when the viscosity of the liquid used varies for each pattern. That is, by appropriately adjusting the area of the protruding portion of the first partition wall according to the viscosity of the liquid as in the above-mentioned production method of the present invention, specifically, by ejecting a relatively low-viscosity liquid In the opening portion of the first partition wall portion, the surface area of the protruding portion of the first partition wall portion is relatively small, and in the opening portion for ejecting a relatively high-viscosity liquid, the surface area of the protruding portion of the first partition wall portion is relatively large, The film thickness of each electro-optical layer can be made uniform and flat.

In the step of forming the partition wall, the protruding length of the first partition wall protruding from the inner surface of the opening of the second partition wall part may be relatively small in the opening part from which the relatively low-viscosity liquid is ejected. , and on the other hand, in the opening from which the relatively high-viscosity liquid is ejected, the protruding length of the first partition wall protruding from the second partition wall is relatively large. By doing so, it is possible to easily adjust the surface area of the protrusion.

In addition, in the present invention, a drying step may be included in which, after the discharge step, the discharged liquids are respectively and simultaneously dried with respect to the various electro-optic layers. By performing drying of the respective electro-optical layers together in this way, the production efficiency of the electro-optical device can be greatly improved compared with conventional ones. Moreover, when drying the electro-optical layers simultaneously, it is preferable to use the same solvent for each electro-optic layer, but when the same solvent is used for different functional materials, the viscosity of each liquid will change. different. Therefore, by adopting the method of the present invention in such a case, it is possible to prevent or suppress problems such as uneven film thickness of the electro-optical device due to the difference in viscosity of the liquid.

The drying step is preferably a vacuum drying step. By using vacuum drying to dry the liquid applied on the substrate, the drying conditions can be finely controlled, and the film thickness uniformity and flatness of the dried electro-optic layer can be improved.

Furthermore, the electro-optical device of the present invention is characterized by being obtained by the above manufacturing method, and the electronic device of the present invention is characterized by including the electro-optical device as a display unit, for example. Such electro-optical devices and electronic devices are low-cost and highly reliable devices and devices.

Description of drawings

FIG. 1 is a circuit diagram showing an organic EL device according to this embodiment.

FIG. 2 is a plan view showing the organic EL device according to the present embodiment.

3 is a cross-sectional configuration diagram showing a display region of the organic EL device according to the present embodiment.

FIG. 4 is a process diagram illustrating a manufacturing method of the embodiment.

FIG. 5 is a process diagram illustrating a manufacturing method of the embodiment.

FIG. 6 is a process diagram illustrating a manufacturing method of the embodiment.

FIG. 7 is a process diagram illustrating a manufacturing method of the embodiment.

FIG. 8 is a process diagram illustrating a manufacturing method of the embodiment.

FIG. 9 is a process diagram illustrating a manufacturing method of the embodiment.

FIG. 10 is a process diagram illustrating the manufacturing method of the embodiment.

Fig. 11 is an enlarged schematic view showing a laminated structure of an inorganic bank layer and an organic bank layer.

FIG. 12 is an explanatory view showing one embodiment of layers formed in the bank portion.

FIG. 13 is an explanatory view showing a different form of layers formed in the bank portion.

Fig. 14 is a plan view showing the configuration of the shower head according to the embodiment.

Fig. 15 is a plan view showing the configuration of the inkjet device according to the embodiment.

FIG. 16 is a perspective view showing an example of an electronic device.

17 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

18 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

19 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

20 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

21 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

22 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

23 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

24 is a schematic cross-sectional view showing the relationship between the shape of the formed film, the viscosity of the liquid composition, and the protrusion width of the banks.

Among the figure: 2—substrate, 110—organic EL layer (electro-optic layer), 110a—hole injection/transport layer, 110b—light-emitting layer, 111—pixel electrode, 112—coffering dam portion (partition wall portion), 112a— Inorganic bank layer (first partition), 112b—organic bank layer (second partition), 112e—first laminated part (protruding part).

Detailed ways

Next, an organic EL device as one embodiment of the electro-optical device of the present invention and a method of manufacturing the organic EL device will be described.

1 is an explanatory diagram showing the wiring structure of the organic EL device of this embodiment, FIG. 2 is a schematic plan view of the organic EL device of this embodiment, and FIG. 3 is a schematic cross-sectional view of a display region of the organic EL device of this embodiment.

(Organic EL device)

As shown in FIG. 1 , the organic EL device of this embodiment has a plurality of scanning lines 101 respectively arranged, a plurality of signal lines 102 extending in a direction intersecting with the scanning lines 101, and a plurality of signal lines 102 extending in a direction parallel to the signal lines 102. There are three power supply lines 103, and a pixel region P is provided near each intersection of the scanning line 101 and the signal line 102.

A data-side drive circuit 104 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102 . In addition, a scanning-side driving circuit 105 including a shift register and a level shifter is connected to the scanning line 101 .

In addition, in each pixel region P, there are provided switching thin film transistors 122 for supplying scanning signals to the gate electrodes through the scanning lines 101, and devices for holding pixel signals supplied from the signal lines 102 through the switching thin film transistors 122. The storage capacitor cap and the driving thin film transistor 123 for supplying the pixel signal held by the storage capacitor cap to the gate electrode flow a driving current from the power supply line 103 when electrically connected to the power supply line 103 via the driving thin film transistor 123. A pixel electrode (electrode) 111 and an organic EL layer 110 sandwiched between the pixel electrode 111 and a cathode (counter electrode) 12 . A light-emitting element is constituted by the electrode 111, the counter electrode 12, and the organic EL layer 110.

When the scanning line 101 is driven and the thin film transistor 122 for switching is turned ON, the potential of the signal line 102 at this time is held by the storage capacitor cap, and the ON/OFF of the thin film transistor 123 for driving is determined according to the state of the storage capacitor cap. state. In addition, the current flows from the power supply line 103 to the pixel electrode 111 through the channel of the thin film transistor 123 for driving, and then flows through the organic EL layer 110 to the cathode 12 . In the organic EL layer 110 , light is emitted according to the amount of current flowing.

As shown in FIG. 3 , the organic EL device of this embodiment includes: a transparent substrate 2 made of glass or the like; The cathode 12 on the element part 11. Here, the display element 10 is constituted by the light emitting element portion 11 and the cathode 12 .

The substrate 2 is, for example, a transparent substrate such as glass, and as shown in FIG. Furthermore, the display region 2a is a region formed of light emitting elements arranged in a matrix.

In addition, in the non-display area 2c, the aforementioned power lines 103 (103R, 103G, 103B) are arranged. On both sides of the display area 2a, the scanning-side driving circuits 105, 105 are arranged. In addition, on both sides of the scanning side driving circuits 105 and 105, the driving circuit control signal wiring 105a and the driving circuit power supply wiring 105b connected to the scanning side driving circuits 105 and 105 are provided. An inspection circuit 106 for inspecting the quality and defects of the display device during the manufacturing process or at the time of shipment is arranged above the display area 2 a in the figure.

In the cross-sectional configuration diagram of FIG. 3 , three pixel regions A are shown. In the organic EL device of this embodiment, on the substrate 2, the circuit element portion 14 formed with a circuit such as a TFT, the light emitting element portion 11 formed with the organic EL layer 110, and the cathode 12 are stacked in this order, and the organic EL layer 110 is stacked on the substrate. The light emitted from the two sides passes through the circuit element portion 14 and the substrate 2 and is emitted to the lower side of the substrate 2 (observer side), and the light emitted from the organic EL layer 110 to the opposite side of the substrate 2 is reflected by the cathode 12 and transmitted. The light passes through the circuit element portion 14 and the substrate 2 and is emitted toward the lower side of the substrate 2 (observer side).

Furthermore, if a transparent material is used as the cathode 12, light emitted from the cathode side can be emitted. Examples of the transparent cathode material include ITO (indium tin oxide), Pt, Ir, Ni, or Pd.

In the circuit element portion 14 , an underprotective film 2 c made of a silicon oxide film is formed on the substrate 2 , and an island-shaped semiconductor film 141 made of polysilicon is formed on the underprotective film 2 c. On the semiconductor film 141, an active region 141a and a drain region 141b are formed by implanting high-density phosphorus ions. The portion where the phosphorus ions are not introduced becomes the channel region 141c.

In addition, a transparent gate insulating film 142 covering the base protective film 2c and the semiconductor film 141 is formed, and a gate electrode 143 made of Al, Mo, Ta, Ti, W, etc. is formed on the gate insulating film 142 ( scanning line 101 ), a transparent first interlayer insulating film 144 a and a second interlayer insulating film 144 b are formed on the gate electrode 143 and the gate insulating film 142 . The gate electrode 143 is provided at a position corresponding to the channel region 141 c of the semiconductor film 141 . In addition, contact holes 145 and 146 respectively connected to the source and drain regions 141a and 141b of the semiconductor film 141 are formed through the first and second interlayer insulating films 144a and 144b.

In addition, a transparent pixel electrode 111 made of ITO or the like is patterned in a predetermined shape on the second interlayer insulating film 144b, and one contact hole 145 is connected to the pixel electrode 111. In addition, the other contact hole 146 is connected to the power line 103 . In this manner, the driving thin film transistor 123 connected to each pixel electrode 111 is formed in the circuit element portion 14 .

The light-emitting element unit 11 is divided by organic EL layers 110 stacked on a plurality of pixel electrodes 111 . . . The part 112 is mainly constituted. A cathode 12 is arranged on the organic EL layer 110 . These pixel electrodes 111, the organic EL layer 110, and the cathode 12 constitute a light emitting element. Here, the pixel electrode 111 is formed of, for example, ITO, and is patterned into a substantially rectangular shape in plan view. The bank part 112 is provided in the shape which partitions each pixel electrode 111....

As shown in FIG. 3 , the dam portion 112 includes an inorganic material dam layer (first dam layer) 112 a as a first barrier wall portion located on the substrate 2 side, and a second barrier wall portion as a second barrier wall portion positioned away from the substrate 2 , as shown in FIG. 3 . The composition of the organic matter bank layer (second bank layer) 112b. The inorganic bank layer 112a is made of, for example, TiO ₂ or SiO ₂ , and the organic bank layer 112b is made of, for example, acrylic resin or polyimide resin.

The inorganic and organic bank layers 112a and 112b are formed to ride on the peripheral portion of the pixel electrode 111 . In a plan view, the periphery of the pixel electrode 111 and the inorganic bank layer 112a are arranged to partially overlap each other. In addition, the organic bank layer 112b is similarly arranged to overlap a part of the pixel electrode 111 in a planar manner. In addition, the inorganic bank layer 112a is formed to protrude toward the center side of the pixel electrode 111 compared to the edge end of the organic bank layer 112b. In this way, by forming each first lamination portion (projection portion) 112e of the inorganic bank layer 112a inside the pixel electrode 111, the lower opening 112c corresponding to the formation position of the pixel electrode 111 is provided.

In addition, an upper opening 112d is formed in the organic bank layer 112b. The upper opening 112d is provided corresponding to the formation position of the pixel electrode 111 and the lower opening 112c. The upper opening 112d is formed wider than the front width of the lower opening 112c and narrower than the pixel electrode 111 as shown in FIG. 3 . In addition, it may be formed such that the upper portion of the upper opening 112 d is substantially at the same position as the end of the pixel electrode 111 . At this time, as shown in FIG. 3 , the cross section of the upper opening 112 d of the organic matter bank layer 112 b becomes inclined. Thus, in the bank part 112, the opening part 112g which connects the lower opening part 112c and the upper opening part 112d is formed.

In addition, in the bank portion 112, a region showing lyophilicity and a region showing lyophobicity are formed. The regions exhibiting lyophilicity are the first laminated portion 112e of the inorganic bank layer 112a and the electrode surface 111a of the pixel electrode 111, and these regions are surface-treated to be lyophilic by plasma treatment using oxygen as a processing gas. In addition, the region showing liquid repellency is the wall surface of the upper opening 112d and the upper surface 112f of the organic bank layer 112, and these regions are treated with tetrafluoromethane, tetrafluoromethane or carbon tetrafluoride as the plasma treatment gas to make the surface Fluorinated (treated for liquid repellency).

The organic EL layer 110 is composed of a hole injection/transport layer 110a laminated on the pixel electrode 111, and a light emitting layer 110b formed adjacent to the hole injection/transport layer 110a.

The hole injection/transport layer 110a has a function of injecting holes into the light emitting layer 110b, and has a function of transporting holes inside the hole injection/transport layer 110a. By providing such a hole injection/transport layer 110a between the pixel electrode 111 and the light emitting layer 110b, device characteristics such as light emitting efficiency and lifetime of the light emitting layer 110b are improved. In addition, in the light-emitting layer 110b, holes injected from the hole injection/transport layer 110a and electrons injected from the cathode 12 recombine in the light-emitting layer to emit light.

The hole injection/transport layer 110a is formed on the first stacked portion 112e of the inorganic bank layer by forming the flat portion 110a1 formed on the pixel electrode surface 111a in the lower opening 112c and in the upper opening 112d. The peripheral portion 110a2 constitutes. In addition, the hole injecting/transporting layer 110a is only formed on the pixel electrode 111 due to structural factors, and is formed between the inorganic bank layers 112a (the lower opening 112c) (it may also be formed only on the aforementioned flat portion). The way).

In addition, the light emitting layer 110b is formed over the flat portion 110a1 and the peripheral portion 110a2 of the hole injection/transport layer 110a, and the thickness on the flat portion 110a1 is set to a range of 50nm to 80nm. The light-emitting layer 110b has three types: a red light-emitting layer 110b1 that emits red (R) light, a green light-emitting layer 110b2 that emits green (G) light, and a blue light-emitting layer 110b3 that emits blue (B) light, as shown in FIG. 2 , the light emitting layers 110b1 to 110b3 are arranged in stripes.

Since the peripheral portion 110a2 having a non-uniform thickness is formed on the first stacked portion 112e of the inorganic bank layer, the peripheral portion 110a2 is insulated from the pixel electrode 111 by the first stacked portion 112e, and holes are not released. It is injected into the light-emitting layer 110b from the peripheral portion 110a2. In this way, the current from the pixel electrode 111 only flows into the flat portion 110a1, and the holes can be uniformly transported from the flat portion 110a1 to the light-emitting layer 110b, and only the central part of the light-emitting layer 110b can be made to emit light, and the light emission of the light-emitting layer 110b can be made even. The amount remains constant.

In addition, since the inorganic bank layer 112a extends toward the center side of the pixel electrode 111 compared with the organic bank layer 112b, the junction portion of the inorganic bank layer 112a to the pixel electrode 111 and the flat portion 110a1 can be utilized. The shape of the light emitting layer 110b can be trimmed to suppress the unevenness of the light emitting intensity among the light emitting layers 110b.

In addition, since the electrode surface 111a of the pixel electrode 111 and the first laminated portion 112e of the inorganic bank layer exhibit lyophilicity, the organic EL layer 110 is uniformly in close contact with the pixel electrode 111 and the inorganic bank layer 112a, The organic EL layer 110 is not extremely thinned on the inorganic bank layer 112a, so that a short circuit between the pixel electrode 111 and the cathode 12 can be prevented.

In addition, since the upper surface 112f of the organic bank layer 112b and the wall surface of the upper opening 112d exhibit liquid repellency, the adhesion between the organic EL layer 110 and the organic bank layer 112b does not decrease, and the organic EL layer 110 is released from the opening 112g. overflow situation.

Furthermore, as a material for forming the hole injection/transport layer, for example, a mixture of polythiophene derivatives such as polyethylenedioxythiophene and polystyrenesulfonic acid can be used. In addition, as the material of the light-emitting layer 110b, for example, (poly)p-phenylene vinylene derivatives, polyphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole, polythiophene derivatives, perylene-based dyes, etc., can be used. , coumarin dyes, rhodamine dyes or rubrene, diphenylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, Coumarin 6, quinacridine (two) ketone, etc. are used.

The cathode 12 is formed on the entire surface of the light emitting element portion 11 , is paired with the pixel electrode 111 , and functions to flow current through the organic EL layer 110 . The cathode 12 is formed by laminating a calcium layer and an aluminum layer, for example. At this time, it is preferable to provide a material with a low work function on the cathode side near the light-emitting layer. In particular, in this mode, it is in direct contact with the light-emitting layer 110b and plays a role of injecting electrons into the light-emitting layer 110b.

In addition, LiF may be formed between the light-emitting layer 110b and the cathode 12 to improve luminous efficiency. Furthermore, the red and green light emitting layers 110b1 and 110b2 are not limited to lithium fluoride, and other materials may be used. Therefore, at this time, a layer made of lithium fluoride may be formed only on the blue (B) light emitting layer 110b3, and a material other than lithium fluoride may be stacked on the other red and green light emitting layers 110b1, 110b2. In addition, lithium fluoride may not be formed on the red and green light emitting layers 110b1 and 110b2, but only calcium may be formed.

In addition, aluminum forming the cathode 12 is a material that reflects light emitted from the light emitting layer 110b toward the substrate 2 side, and is preferably composed of an Ag film or a laminated film of Al and Ag in addition to the Al film. In addition, a protective layer for preventing oxidation made of SiO, SiO ₂ , SiN or the like may be provided on aluminum.

In the light emitting element portion 11 shown in FIG. 3 , there is a sealing portion in an actual organic EL device. The sealing portion can be formed, for example, by applying a sealing resin annularly around the substrate 2 and then sealing it with a sealing pot. The sealing resin is preferably made of a thermosetting resin, an ultraviolet curable resin, or the like, and is particularly preferably made of an epoxy resin that is a kind of thermosetting resin. This sealing portion is provided to prevent oxidation of the cathode 12 or the light-emitting layer formed in the light-emitting element portion 11 . In addition, a gas absorbent for absorbing water, oxygen, and the like may be provided inside the airtight can, so that water or oxygen intruding into the airtight can can be absorbed.

(Manufacturing method of organic EL device)

A method of manufacturing the organic EL device will be described below with reference to the drawings.

The production method of this embodiment includes (1) bank portion forming step, (2) hole injection/transport layer forming step, (3) light emitting layer forming step, (4) cathode forming step, (5) sealing step, and the like. Furthermore, the manufacturing method described here is an example, and other steps may be added or part of the steps described above may be deleted as necessary. Furthermore, (2) the hole injection/transport layer forming step and (3) the light emitting layer forming step were performed using a liquid discharge method (inkjet method) using a droplet discharge device.

In addition, in the production method of this embodiment, in (3) the light emitting layer forming step, the liquid composition to be ejected onto the substrate 2 is composed of a common mixed solvent for the light emitting layer forming liquid composition of each color, After the discharge of all the liquid compositions for the respective colors is completed, a drying step is performed together.

(1) Cofferdam part forming process

In the dam portion forming step, the dam portion 112 is formed at a predetermined position on the substrate 2 . The bank portion 112 has a structure in which an inorganic material bank layer 112a is formed as a first bank layer and an organic material bank layer 112b is formed as a second bank layer.

(1)-1 Formation of the inorganic bank layer 112a

First, as shown in FIG. 4 , an inorganic bank layer 112 a is formed at a predetermined position on the substrate. The position where the inorganic bank layer 112a is formed is on the second interlayer insulating film 144b and the pixel electrode 111 . Furthermore, the second interlayer insulating film 144b is formed on the circuit element portion 14 in which the thin film transistors, scanning lines, signal lines, and the like are disposed. The inorganic bank layer 112a can be made of inorganic materials such as SiO ₂ and TiO ₂ , for example. These materials are formed by, for example, a CVD method, a coating method, a sputtering method, a vapor deposition method, or the like. In addition, the film thickness of the inorganic bank layer 112a is preferably in the range of 50 nm to 200 nm, particularly preferably 150 nm.

The inorganic bank layer 112a is formed in a shape having an opening by forming an inorganic film on the entire surface of the interlayer insulating film 144 and the pixel electrode 111, and then patterning the inorganic film by photolithography or the like. The opening is a portion corresponding to the position where the electrode surface 111a of the pixel electrode 111 is formed, and is provided as a lower opening 112c as shown in FIG. 4 . In addition, at this time, the inorganic bank layer 112a is formed so as to partially overlap the peripheral portion of the pixel electrode 111, so that the planar light emitting region of the light emitting layer 110 can be suppressed.

(1)-2 Formation of organic cofferdam layer 112b

Then, the organic material bank layer 112b as the second bank layer is formed.

Specifically, as shown in FIG. 4, the organic bank layer 112b is formed on the inorganic bank layer 112a. As a material constituting the organic bank layer 112b, a material having heat resistance and solvent resistance such as acrylic resin or polyimide resin is used. Using these materials, the organic bank layer 112b is patterned and formed by photolithography or the like. Furthermore, when patterning is performed, the upper opening 112d is formed in the organic bank layer 112b. The upper opening 112d is provided at a position corresponding to the electrode surface 111a and the lower opening 112c.

As shown in FIG. 4, the upper opening 112d is preferably formed wider than the lower opening 112c formed in the inorganic bank layer 112a. In addition, the best cross-sectional shape of the organic bank layer 112b forms a tapered shape, and it is preferable that the bottom surface of the organic bank layer 112b is narrower than the width of the pixel electrode 111, and the uppermost surface of the organic bank layer 112b is connected to the pixel electrode. 111 is about the same width.

Thus, the first stacked portion 112e surrounding the lower opening 112c of the inorganic bank layer 112a protrudes toward the center of the pixel electrode 111 more than the organic bank layer 112b. In this way, by connecting the upper opening 112d formed on the organic bank layer 112b and the lower opening 112c formed on the inorganic bank layer 112a, a hole that penetrates the inorganic bank layer 112a and the organic bank layer 112b is formed. The opening 112g. Furthermore, in the present embodiment, the amount of protrusion of the portion of the inorganic bank layer 112a protruding toward the center side of the pixel electrode 111 is different for each pixel. Specifically, for each light emitting layer 110b1, 110b2 and 110b3 employ different protrusion amounts.

In addition, the thickness of the organic bank layer 112b is preferably in the range of 0.1 μm to 3.5 μm, particularly preferably about 2 μm. The reason for adopting such a range is as follows.

That is, if the thickness is less than 0.1 μm, since the organic bank layer 112b is thinner than the total thickness of the hole injection/transport layer and the light emitting layer described later, the light emitting layer 110b may protrude from the upper opening 112d. Not ideal. In addition, when the thickness exceeds 3.5 μm, the step due to the upper opening 112 d becomes large, and the step coverage of the cathode 12 on the upper opening 112 d cannot be ensured, which is not preferable. In addition, if the thickness of the organic material bank layer 112b is set to 2 μm or more, it is preferable from the viewpoint of improving the insulation between the cathode 12 and the driving thin film transistor 123 .

In addition, the surface of the formed dam portion 112 and the surface of the pixel electrode 111 is preferably subjected to appropriate surface treatment by plasma treatment, specifically, the surface of the dam portion 112 is treated to be lyophobic and the surface of the pixel electrode 111 is made to be lyophilic. deal with.

First, the surface treatment of the pixel electrode 111 can be carried out by using O ₂ plasma treatment using oxygen, for example, at a plasma power of 100kW-800kW, an oxygen flow rate of 50ml/min-100ml/min, and a plate transport speed of 0.5mm/sec. The region including the surface of the pixel electrode 111 can be made lyophilic by performing the treatment under the conditions of ~10 mm/sec and a substrate temperature of 70° C. to 90° C. In addition, the cleaning of the surface of the pixel electrode 111 and the adjustment of the work function may be performed simultaneously by the O ₂ plasma treatment.

Then, the surface treatment of the cofferdam part 112 can be carried out by _CF4 plasma treatment using tetrafluoromethane, for example, by plasma power 100kW-800kW, tetrafluoromethane flow rate 50ml/min-100ml/min, substrate transport speed The upper opening 112d and the upper surface 112f of the dam portion 112 can be made liquid-repellent by processing under the conditions of 0.5 mm/sec to 10 mm/sec and a substrate temperature of 70° C. to 90° C.

(2) Hole injection/transport layer formation process

Then, in the light-emitting element forming process, first, a hole injection/transport layer is formed on the pixel electrode 111 .

In the hole injection/transport layer forming step, a liquid composition containing a hole injection/transport layer forming material is discharged onto the electrode surface 111 a by using, for example, an inkjet device as a droplet discharge device. Thereafter, drying treatment and heat treatment are performed to form the hole injection/transport layer 110a on the pixel electrode 111 and the inorganic bank layer 112a. Here, the hole injection/transport layer 110a may not be formed on the first laminated portion 112e, that is, the hole injection/transport layer may be formed only on the pixel electrode 111.

The manufacturing method by inkjet is as follows. That is, as shown in FIG. 5 , a liquid composition containing a hole injection/transport layer forming material is ejected from a plurality of nozzles formed on the inkjet head H1. Here, although the composition is filled in each pixel by scanning the inkjet head, it may also be performed by scanning the substrate 2 . In addition, the composition can also be filled by relatively moving the inkjet head and the substrate 2 . In addition, in subsequent steps using the inkjet head, the above points are the same.

The discharge by the inkjet head is as follows. That is, the discharge nozzle H2 formed in the inkjet head H1 is arranged so as to face the electrode surface 111, and the liquid composition is discharged from the nozzle H2. Around the pixel electrode 111, a dam 112 that divides the lower opening 112c is formed, and the ink jet head H1 faces the pixel electrode surface 111a located in the lower opening 112c. While the substrate 2 is relatively moving, droplets 110c of the liquid composition are ejected from the ejection nozzle H2 onto the electrode surface 111a with a controlled amount of each droplet.

As the liquid composition used in this step, for example, a composition obtained by dissolving a mixture of a polythiophene derivative such as polyethylenedioxythiophene (PEDOT) and polystyrenesulfonic acid (PSS) in a polar solvent can be used. As the polar solvent, for example, isopropanol (IPA), n-butanol, γ-butyrolactone, N-methylpyrrolidone (NMP), 1,3-dimethyl-2-imidazolidinone (DMI ) and its derivatives, glycol ethers such as carbitol acetate, butyl carbitol acetate, etc.

Examples of a more specific composition include PEDOT/PSS mixture (PEDOT/PSS=1:20): 12.52% by weight, IPA: 10% by weight, NMP: 27.48% by weight, and DMI: 50% by weight. Furthermore, the viscosity of the liquid composition is preferably about 1 mPa·s to 20 mPa·s, particularly preferably about 4 mPa·s to 15 mPa·s.

By using such a liquid composition, it becomes possible to discharge stably without clogging in the discharge nozzle H2. Furthermore, the same material may be used for the red (R), green (G), and blue (B) light-emitting layers 110b1 to 110b3 as the material for forming the hole injection/transport layer, or it may be used alternately for each light-emitting layer. In this embodiment, different hole injection/transport layer forming materials are used for the red (R), green (G), and blue (B) light-emitting layers 110b1-110b3, and the liquid ejected to the light-emitting layers 110b1-110b3 The compositions vary in viscosity.

Here, when liquid compositions having different viscosities are ejected, the film thickness of the formed hole injection/transport layer may become non-uniform due to the difference in viscosity. Specifically, as shown in FIG. 12, when the viscosity of the liquid composition used is low (for example, 1 mPa·s), the film thickness of the formed layer 201 is just in the peripheral portion (here, close to the inorganic material bank layer). 112a), on the other hand, when the viscosity of the liquid composition is high (for example, 20mPa·s), then as shown in Figure 13, the film thickness of the formed layer 202 has a central tendency to grow larger.

On the other hand, independently of the viscosity, the formed hole injection/transport layer may be affected by the surface area of the portion (first lamination portion) 112e protruding from the organic bank layer 112a in the inorganic bank layer 112a. The case where the film thickness becomes non-uniform. Specifically, when the surface area of the protruding portion 112e of the inorganic bank layer 112a is large, the film thickness of the formed layer tends to increase at the peripheral portion (the side closer to the partition wall portion), and on the other side. On the other hand, when the surface area of the protruding portion 112e of the inorganic bank layer 112a is small, the film thickness of the formed layer tends to increase in the central portion. In addition, specifically, when the protruding width (the width L1 shown in FIG. 11 ) of the protruding portion 112e of the inorganic bank layer 112a is about 5 μm, the film thickness of the formed layer has a thickness at the peripheral portion (close to one side of the partition wall) becomes larger (see FIG. 12 ), on the other hand, when the protruding width (width L1 shown in FIG. 11 ) of the protruding portion 112e of the inorganic bank layer 112a is about 1 μm, the formed The film thickness of the layer tends to increase in the center (see FIG. 13 ).

Therefore, in this embodiment, since the viscosities of the liquid compositions ejected to the light emitting layers 110b1 to 110b3 of the respective colors are different, the surface area of the protruding portion 112e of the inorganic bank layer 112a is adjusted in advance for each of the light emitting layers 110b1 to 110b3 (that is, Pixels of each color) are different, thereby preventing or suppressing the formation of a non-uniform hole injecting/transporting layer. Specifically, in a pixel that ejects a liquid composition with a relatively high viscosity, the amount of protrusion of the protrusion 112e is increased to increase the surface area of the protrusion 112e, and in a pixel that ejects a liquid composition with a relatively low viscosity. In the pixel of the composition, the protrusion amount of the protrusion 112e is reduced, and the surface area of the protrusion 112e is reduced.

Returning to FIG. 5 , droplets 110c of the ejected composition spread on the lyophilic-treated electrode surface 111a and the first laminated portion 112e, and are filled in the lower and upper openings 112c, 112d. Even if the first composition droplet 110c deviates from the prescribed ejection position and is sprayed onto the upper surface 112f, the upper surface 112f will not be wetted by the first composition droplet 110c, and the bounced first composition droplet 110c will roll. into the lower and upper openings 112c, 112d.

The amount of the composition ejected onto the electrode surface 111a depends on the size of the lower and upper openings 112c and 112d, the thickness of the hole injection/transport layer to be formed, and the amount of the hole injection/transport layer forming material in the liquid composition. concentration etc. In addition, the droplets 110c of the liquid composition may be sprayed onto the same electrode surface 111a not only once but divided into several times. In this case, the amount of the liquid composition may be the same each time, or the liquid composition may be changed each time. In addition, the liquid composition may be discharged not only to the same position on the electrode surface 111a, but also to different positions within the electrode surface 111a each time.

For the configuration of the inkjet head, a head H as shown in FIG. 14 can be used. In addition, it is preferable to arrange the substrate and the inkjet head as shown in FIG. 15 .

In FIG. 14 , reference numeral H7 is a support substrate for supporting the aforementioned inkjet head H1 , and a plurality of inkjet heads H1 are provided on the support substrate H7 .

On the ink ejection surface (surface opposite to the substrate) of the inkjet head H1, a plurality of (for example, 1 180 nozzles in a row, a total of 360 nozzles) discharge nozzles. In addition, the inkjet head H1 directs the ejection nozzles toward the substrate side, and in a state of being inclined by a predetermined angle with respect to the X-axis (or Y-axis), approximately in a row along the X-axis direction, and in a row along the Y-axis. They are positioned and supported at a plurality of positions (6 in one row in FIG. 14 , 12 in total) in a state of being arranged in two rows at predetermined intervals on a substantially rectangular support plate 20 in plan view.

In the inkjet head device shown in FIG. 15 , reference numeral 1115 denotes a stage on which the substrate 2 is placed, and reference numeral 1116 denotes a guide rail for guiding the stage 1115 along the x-axis direction (main scanning direction) in the figure. In addition, the printhead H can move along the y-axis direction (sub-main scanning direction) in the figure by means of the support member 1111 and the guide rail 1113. In addition, the printhead H can rotate along the θ-axis direction in the figure, so that the inkjet head H1 can be moved relative to the The main scanning direction is inclined by a predetermined angle. In this way, by arranging the inkjet head obliquely with respect to the scanning direction, the nozzle pitch can be made to correspond to the pixel pitch. In addition, by adjusting the tilt angle, it can be made to correspond to any pixel pitch.

The substrate 2 shown in FIG. 15 has a structure in which a plurality of chips are arranged on a mother substrate. That is, the area of one chip corresponds to one display device. Here, although three display regions 2a are formed, it is not limited thereto. For example, when coating the composition on the left display area 2a on the substrate 2, the nozzle H is moved to the left in the figure by the guide rail 1113, and the substrate 2 is moved to the upper side in the figure by the guide rail 1116. , coating is performed while scanning the substrate 2 . The same applies to the display area 2 a located at the right end. Furthermore, the head H shown in FIG. 14 and the inkjet device shown in FIG. 15 are used not only in the hole injection/transport layer forming process but also in the light emitting layer forming process.

Then, a drying process as shown in FIG. 6 is performed. That is, the sprayed first composition is dried to evaporate the solvent contained in the first composition to form the hole injection/transport layer 110a. When the drying process is performed, the evaporation of the solvent contained in the liquid composition is mainly caused when the inorganic material bank layer 112a and the organic material bank layer 112b are approached, and the hole injection/transport layer is concentrated together with the evaporation of the solvent. Precipitate. In this way, as shown in FIG. 6 , a peripheral portion 110a2 made of a material for forming a hole injection/transport layer is formed on the first laminated portion 112e. The peripheral portion 110a2 is in close contact with the wall surface of the upper opening 112d (the organic matter bank layer 112b), and its thickness becomes thinner on the side closer to the electrode surface 111a, and becomes thinner on the side away from the electrode face 111a, that is, near the organic matter bank layer 112b. thickened on one side.

Also, at the same time, the solvent evaporates on the electrode surface 111a due to the drying process, so that a flat portion 110a1 made of a hole injection/transport layer forming material is formed on the electrode surface 111a. Since the evaporation rate of the solvent is substantially uniform on the electrode surface 111a, the material for forming the hole injection/transport layer is uniformly concentrated on the electrode surface 111a, thereby forming a flat portion 110a1 of uniform thickness. In this way, the hole injection/transport layer 110a composed of the peripheral portion 110a2 and the flat portion 110a1 is formed. Furthermore, it is also possible to form a hole injection/transport layer only on the electrode surface 111a without forming it on the peripheral portion 110a2.

The above-mentioned drying treatment is performed, for example, in a nitrogen atmosphere at room temperature and at a pressure of, for example, about 133.3 Pa (1 Torr). When the pressure is too low, it is not preferable because the liquid droplets 110c of the composition boil. In addition, when the temperature is higher than room temperature, the evaporation rate of the polar solvent increases, and a flat film cannot be formed. After the drying treatment, the polar solvent or water remaining in the hole injection/transport layer 110 a is removed by heating in nitrogen gas, preferably at 200° C. for about 10 minutes in vacuum.

In the hole injecting/transporting layer forming step described above, the ejected composition droplets 110c are filled in the lower and upper openings 112c, 112d. The liquid composition in the barrier layer 112b is bounced off and rolled into the lower and upper openings 112c and 112d. In this way, the liquid droplets 110c of the ejected composition can certainly be filled in the lower and upper openings 112c, 112d, and the hole injection/transport layer 110a can be formed on the electrode surface 111a.

(3) Emitting layer formation process

The light emitting layer forming step is composed of a light emitting layer forming material discharging step and a drying step.

The liquid composition for forming the light-emitting layer is discharged onto the hole injection/transport layer 110a by the inkjet method in the same manner as in the above-mentioned hole injection/transport layer forming step. Thereafter, the discharged liquid composition is subjected to drying treatment (and heat treatment) to form the light emitting layer 110b on the hole injection/transport layer 110a.

Fig. 7 shows a discharge step of discharging a liquid composition containing a material for forming a light-emitting layer by inkjet. As shown in the figure, the inkjet head H5 and the substrate 2 are relatively moved, and liquid combinations containing light-emitting layer forming materials of various colors (for example, blue (B) in this case) are ejected from the ejection nozzles H6 formed on the inkjet head. thing.

When ejecting, the ejection nozzles are made to face the hole injection/transport layer 110a located in the lower and upper openings 112c and 112d, and while the inkjet head H5 and the substrate 2 are relatively moved, a liquid-like layer is ejected. combination. The liquid amount per drop of the liquid amount ejected from the ejection nozzle H6 is controlled. The liquid (liquid composition droplet 110e) whose liquid amount is thus controlled is discharged from the discharge nozzle, and the liquid composition droplet 110e is discharged onto the hole injection/transport layer 110a.

In this embodiment, the discharge of another liquid composition for a light-emitting layer is performed continuously with the arrangement of the liquid composition droplet 110e. That is, as shown in FIG. 8 , the liquid composition droplets 110 f and 110 g are ejected and arranged without drying the liquid composition droplets 110 e dropped onto the substrate 2 . When the liquid composition droplets 110e to 110g for forming the light emitting layers 110b1 to 110b3 of the respective colors are dropped in this way, a plurality of nozzles filled with the liquid compositions for the respective colors may be independently scanned. The arrangement of the liquid composition droplets 110e to 110g on the substrate 2 can also be performed substantially simultaneously by scanning the plurality of heads integrally.

As shown in FIG. 8 , the ejected liquid compositions 110e to 110g spread over the hole injection/transport layer 110a and fill the lower and upper openings 112c and 112d. On the other hand, even if liquid composition droplets 110e to 110g are ejected onto the upper surface 112f from the predetermined ejection position on the upper surface 112f subjected to the lyophobic treatment, the upper surface 112f will not be covered by the liquid composition. The droplets 110e to 110g are infiltrated, and the liquid composition droplets 110e to 110g roll into the lower and upper openings 112c and 112d.

The amount of the liquid composition ejected onto each hole injection/transport layer 110a is determined by the size of the lower and upper openings 112c and 112d, the thickness of the light emitting layer 110b to be formed, the concentration of the light emitting layer material in the liquid composition, and the like. In addition, the liquid compositions 110e to 110g may be sprayed onto the same hole injection/transport layer 110a not only once but divided into several times. At this time, the amount of the liquid composition may be the same each time, or the liquid amount of the liquid composition may be changed each time. In addition, not only the same position in the hole injection/transport layer 110a may be ejected, but the liquid composition may be ejected to different positions in the hole injection/transport layer 110a each time.

As the light-emitting layer forming material, polyfluorene-based polymer derivatives, (poly)p-phenylene vinylene derivatives, polyphenylene derivatives, polyvinylcarbazole, polythiophene derivatives, perylene-based dyes, Coumarin-based dyes, rhodamine-based dyes, or doping organic EL materials into the polymers. For example, it can be used by doping rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6, quinacridone or the like. In addition, as solvents for dissolving or dispersing these light-emitting layer-forming materials, the same kind of solvents are used for each color light-emitting layer.

Here, in the same manner as the formation process of the hole injection/transport layer, when liquid compositions made of different materials, that is, liquid compositions with different viscosities are discharged, due to the difference in viscosity, the formed light-emitting layer The film thickness will become uneven. Therefore, in the present embodiment, the surface area of the protruding portion 112e of the inorganic bank layer 112a is made different in advance for each light emitting layer 110b1 to 110b3 (that is, for each color pixel) to prevent or suppress the formation of a light emitting layer with an uneven film thickness. Case. Specifically, in a pixel that ejects a liquid composition with a relatively high viscosity, the amount of protrusion of the protrusion 112e is increased to increase the surface area of the protrusion 112e, and in a pixel that ejects a liquid composition with a relatively low viscosity. In the pixel of the object, the protrusion amount of the protrusion 112e is reduced, and the surface area of the protrusion 112e is reduced.

Then, after the liquid compositions 110e to 110g for the respective colors are arranged at predetermined positions, they are dried together to form the light emitting layers 110b1 to 110b3. That is, the solvent contained in the liquid composition droplets 110e to 110g is evaporated by drying to form a red (R) light-emitting layer 110b1, a green (G) light-emitting layer 110b2, and a blue (B) light-emitting layer as shown in FIG. 9 . 110b3. Moreover, although FIG. 9 shows one light-emitting layer emitting red, green, and blue light, it can be clearly seen from FIG. 1 or other figures that the light-emitting elements are originally formed in a matrix. A plurality of light-emitting layers (corresponding to each color) are shown in the figure.

In addition, drying of the liquid composition of the light-emitting layer is preferably performed by vacuum drying, and if a specific example is to be given, it can be performed under conditions of a pressure of about 133.3 Pa (1 Torr) at room temperature in a nitrogen atmosphere. When the pressure is too low, the liquid composition is not preferable because of bumping. In addition, when the temperature is higher than room temperature, since the evaporation rate of the solvent increases, the material for forming the light emitting layer excessively adheres to the wall surface of the upper opening 112d, which is not preferable.

Then, after the vacuum drying is completed, it is preferable to anneal the light emitting layer 110b using a heating means such as a hot plate. This annealing treatment is performed at a common temperature and time for maximizing the emission characteristics of each organic EL layer.

Thus, on the pixel electrode 111, the hole injection/transport layer 110a and the light emitting layer 110b are formed.

Furthermore, a surface modification step for surface modification of the surface of the hole injection/transport layer 110a may be performed before the discharge step of the light-emitting layer forming material.

In the light emitting layer forming step, in order to prevent redissolution of the hole injection/transport layer 110a, it is preferable to use a solvent that does not dissolve the hole injection/transport layer 110a as a solvent of the liquid composition used when forming the light emitting layer. However, on the other hand, since the hole injection/transport layer 110a has a low affinity for solvents, even if a liquid composition containing a solvent is ejected onto the hole injection/transport layer 110a, there is a possibility that the hole injection/transport layer 110a cannot be injected/transported. The transport layer 110a and the light-emitting layer 110b are in close contact, or the light-emitting layer 110b cannot be uniformly coated. Therefore, in order to improve the affinity of the surface of the hole injection/transport layer 110a to the solvent and the material for forming the light emitting layer, it is preferable to perform a surface modification step before forming the light emitting layer.

In the surface modification step, the surface modification material that is the same solvent as the solvent of the liquid composition used in the formation of the light-emitting layer or a solvent similar thereto can be used by inkjet method (droplet discharge method), spin coating, etc. The hole injecting/transporting layer 110 a is coated by coating or dipping and then dried. As the surface modifying material used here, as the same solvent as the solvent of the liquid composition, cyclohexylbenzene, isopropyl biphenyl, trimethylbenzene, etc. can be enumerated, as the solvent similar to the liquid composition As the solvent, tetramethylbenzenetoluene, toluene, xylene, etc. can be mentioned.

(4) Cathode forming process

Then, as shown in FIG. 10, a cathode 12 paired with a pixel electrode (anode) 111 is formed. That is, the cathode 12 is formed, for example, in which a calcium layer and an aluminum layer are sequentially stacked on the entire area of the substrate 2 including the light emitting layers 110b of each color and the organic bank layer 112b. In this way, the cathode 12 is covered over the entire region where the light emitting layers 110b of the respective colors are formed, and organic EL elements corresponding to the respective colors of red, green, and blue are respectively formed.

Cathode 12 is preferably formed by, for example, vapor deposition, sputtering, or CVD, and is particularly preferably formed by vapor deposition from the viewpoint of preventing heat-induced damage to light-emitting layer 110b. In addition, a protective layer such as SiO ₂ or SiN may be provided on the cathode 12 in order to prevent oxidation.

(5) Sealing process

Finally, the substrate 2 on which the organic EL element was formed and the separately prepared sealing substrate were sealed with a sealing resin. A sealing resin made of, for example, a thermosetting resin or an ultraviolet curing resin is applied to the peripheral portion of the substrate 2, and the sealing substrate is arranged on the sealing resin. The sealing process is preferably performed in an inert gas atmosphere such as nitrogen, argon, or helium. In the air, if a defect such as a pinhole is generated in the cathode 12, water, oxygen, etc. may intrude through the defect and oxidize the cathode 12, which is not preferable.

Thereafter, the organic EL device of this embodiment is completed by connecting the cathode 12 to the wiring of the substrate 2 and connecting the wiring of the circuit element portion 14 to a driver IC (driver circuit) provided on the substrate 2 or outside.

When using the above-mentioned production method, in the case where the viscosity of the liquid composition used is different for each color light-emitting layer (that is, for each pixel), it is also possible to store the inorganic material according to the viscosity of the liquid composition. The area of the protruding portion 112e of the layer 112a is appropriately adjusted. As a result, the film thicknesses of the respective light emitting layers 110b1 to 110b3 can be made uniform and flat, and an organic EL device having excellent optical characteristics can be manufactured. Furthermore, in this method, since only the protrusion amount of the protrusion part 112e of the inorganic bank layer 112a is adjusted, it is very simple.

In this embodiment mode, although the organic EL device and its manufacturing method have been described, the present invention can also be applied to a manufacturing method of a color filter substrate in which multi-color color material layers are arranged and formed, and a semiconductor device including an organic TFT or the like. Of course, in the manufacturing method of the device in the color filter or device manufacturing method of the present invention, the effect of improving the flatness of the formed color material layer or functional layer can also be obtained.

Here, the film shape (especially surface shape) of each layer formed in the bank layer 112 in the above-mentioned manufacturing process, the viscosity of the liquid composition used in the film formation, and the inorganic material bank layer 112a The relationship between the protrusion amount (protrusion width) of the protruding portion (first lamination portion) 112e will be described in detail.

First, Fig. 17(a)-(e) are on the substrate with the bank layer 112 having the same structure, that is, the protruding width L1 of the protruding portion 112e to the inorganic bank layer 112a is each the same (here L1=3 μm ) on a substrate, a schematic cross-sectional view showing the difference in the shape of the resulting film 200 when liquid compositions with different viscosities η (mPa·s) are ejected. When liquid compositions having different viscosities are ejected to form a film in this way, the surface shape of the obtained film 200 changes due to the difference in viscosity. That is, for the case of low viscosity (Fig. 17(a) and (b)), the film 200 becomes concave, and its cross-sectional shape becomes U-shaped. On the contrary, for the case of high viscosity (Fig. 17(e) and (d) )), the film 200 becomes convex, and its cross-sectional shape becomes an inverted U shape.

On the other hand, Fig. 18 (a) ~ (e) is for the liquid composition of the same viscosity (here η = 14mPa·s) on the substrate equipped with different bank layers 112 of various shapes, that is, on the inorganic A schematic cross-sectional view showing the difference in the shape of the obtained film 200 when the projecting width L1 of the projecting portion 112e of the object bank layer 112a is different when ejected. When a liquid composition having the same viscosity is sprayed onto substrates having different protrusion widths L1 of the protrusions 112e to form a film, the surface shape of the obtained film 200 also changes due to the difference in viscosity. That is, when the protrusion width L1 is large ( FIG. 18( a )), the film 200 becomes concave, and its cross-sectional shape becomes U-shaped. On the contrary, for the case where the protrusion width L1 is small ( FIG. 18 ( e )), the film 200 becomes convex, and its cross-sectional shape becomes an inverted U shape.

17 and 18, it is found that the shape of the film 200 can be controlled in various ways by utilizing the viscosity of the liquid composition and the protrusion amount of the protrusion 112e (that is, the surface area of the protrusion 112e). That is, this is because, although in the example shown in Fig. 17 and Fig. 18, when using the liquid composition of viscosity η=14mPa·s, and under the situation that the protruding width L1 of protruding portion 112e is set to 3 μm, it is possible to form The surface shape of the film 200 is flat, but as shown in FIG. 19, for example, in the case of using a liquid composition with a relatively low viscosity (η=4mPa·s), by making the protrusion width L1 relatively small (L1=1μm), The film 200 can be formed with a flat surface shape. On the other hand, as shown in FIG. 20, for example, in the case of using a relatively high viscosity (η=24mPa·s) liquid composition, the surface shape can be formed by making the protrusion width L1 relatively large (L1=5μm). Flat membrane 200 .

However, when a two-layer bank is formed on the substrate as in the present embodiment, the bank on the lower layer is formed into a protruding shape, and a single layer is formed in the bank by a droplet discharge method. In the case of a functional film, flattening of the surface shape of the functional film can be achieved as follows. Specifically, as shown in FIG. 21, when forming a color filter as a functional layer, in the process of forming a red layer 200R, a green layer 200G, and a blue layer 200B, if the If the viscosity of the liquid composition is uniform for each color R, G, and B, a flat color filter can be obtained by making the shape of the banks of each color R, G, and B the same. That is, by setting the protruding width of the protruding portion 112e of the lower layer (inorganic material dam layer) 112a as L2=L3=L4=3 μm for the dams for forming the color layers 200R, 200G, and 200B, for the dams used for forming The liquid composition of each color layer 200R, 200G, 200B can flatten the surface shape of each color layer 200R, 200G, 200B obtained by setting the viscosity as ηR=ηG=ηB=14mPa·s.

In addition, since the materials constituting the color layers 200R, 200G, and 200B are different, the viscosity of the liquid compositions of each color is determined by changing the solvent type for each color, or by changing the concentration for each color, or by changing the viscosity of the liquid composition according to the situation. Different molecular weights of constituent materials can be unified for each color.

On the other hand, assuming that the viscosities of the liquid compositions of each color are different from each other for ηR=4mPa·s, ηG=14mPa·s, and ηB=24mPa·s as shown in Figure 21(b), the lower layer of the cofferdam (Inorganic bank layer) 112a When the protrusion width of the protrusion 112e is set to L2 = L3 = L4 = 3 μm and uniform, the red layer 200R formed of a low-viscosity liquid composition will have a concave surface shape, The blue layer 200B formed from the high-viscosity liquid composition has a convex surface shape.

Therefore, when the viscosities of the liquid compositions of each color are different, as shown in FIG. Different color layers 200R, 200G, and 200B can be formed with flat surface shapes. Specifically, in the red layer 200R using a liquid composition with a viscosity ηR=4mPa·s, the protrusion width L2 of the dam is set to 1 μm, and in the green layer 200G using a liquid composition with a viscosity ηG=14mPa·s, The protrusion width L3 of the bank was set to 3 μm, and in the blue layer 200B using a liquid composition with a viscosity ηB=24 mPa·s, the protrusion width L4 of the bank was set to 5 μm, which can be optimized. Furthermore, since the viscosity of the liquid composition differs depending on the dischargeability, solubility, composition, etc., it generally differs for each functional film to be formed. Even in this case, by making the protrusion width of the lower layer (inorganic bank layer) of the bank composed of two layers different for each of the functional films as described above, it is also possible to form the respective surface shapes flat, Functional film with uniform film thickness.

On the other hand, in the organic EL device of the present embodiment described above, since the constituent materials of the light-emitting layers 110b1 to 110b3 of the respective colors are different, under normal conditions (same solvent, same concentration), the liquid combination for forming the light-emitting layer For each color, the viscosity of the substance will be different. On the other hand, since the hole injection/transport layer 110a formed under the light emitting layer 110b has the same constituent materials for each color, it is used to form the hole injection/transport layer 110a under normal conditions (same solvent, same concentration). The viscosity of the liquid composition of the transport layer 110a is unified for each color.

Therefore, as shown in FIG. 22(a), in order to obtain a flat film for the hole injection/transport layers 110aR, 110aG, and 110aB, the viscosity of the liquid composition is unified to ηaR=ηaG=ηaB=14mPa·s, In addition, when the protrusion width of the inorganic bank layer 112a is uniformly L2=L3=L4=3 μm, as shown in FIG. When the concentration of the substance is uniform, the light-emitting layer 110b having a flat surface shape can be formed. In addition, here, in order to set the viscosity of the liquid composition for forming the light-emitting layers 110b1, 110b2, and 110b3 of each color to ηbR=ηbG=ηbB=14mPa·s, different types of solvents are used for the liquid compositions of each color.

In the case where the protruding widths L2, L3, and L4 of the inorganic bank layer 112a are unified for each color as described above, it can be combined with the hole injection/transport layer 110a and the light emitting layer 110b by combining the used liquid The viscosity of the material is uniform for each color, and each flat film shape is obtained.

On the other hand, when forming the light-emitting layers 110b1, 110b2, and 110b3, if the liquid composition is composed of the same type of solvent and the same concentration for each color, the liquid composition for forming the light-emitting layer will become the Compositions with different viscosities for each color. Specifically, as shown in FIG. 23, for the red light-emitting layer 110bR viscosity ηbR=4mPa·s, for the green light-emitting layer 110bG viscosity ηbG=14mPa·s, for the blue light-emitting layer 110bB viscosity ηbB=24mPa·s Case. In this case, when the protrusion width of the inorganic bank layer 112a is unified to L2=L3=L4=3 μm as shown in FIG. , the surface has a concave shape, and in the high-viscosity (ηbB=24mPa·s) blue light emitting layer 110b3, the surface has a convex shape.

Therefore, when the viscosity of the liquid composition for forming the light emitting layer is different for each color, as shown in FIG. 24, by making the protrusion width of the inorganic bank layer 112a different for each color, A light-emitting layer with a flat surface shape is formed in each color. Specifically, in the banks forming the red light emitting layer, L2=1 μm, in the bank forming the green light emitting layer, L3=3 μm, in the bank forming the blue light emitting layer, L4=5 μm .

Furthermore, when the protruding width of the bank is different for each color, the liquid composition of the hole injection/transport layer 110a serving as the lower layer of the light emitting layer 110b is also required to form the layer 110a in a flat state. It is necessary to make the viscosity different for each color. Here, as shown in FIG. 24(a), the viscosity ηaR=4mPa·s for the red hole injection/transport layer 110aR, the viscosity ηaG=14mPa·s for the green hole injection/transport layer 110aG, and the blue The hole injection/transport layer 110aB has a viscosity ηaB=24mPa·s. In this way, also for the hole injection/transport layer 110a, a layer with a flat surface shape can be obtained. In addition, the light emitting layers 110b1, 110b2, and 110b3 can be formed by spraying liquid compositions having the above-mentioned viscosities onto the hole injection/transport layer 110a, and a flat surface shape can also be obtained for the light emitting layer 110b. layer.

(Electronic equipment)

FIG. 16 shows an embodiment of the electronic device of the present invention. The electronic device of this embodiment includes the above-mentioned organic EL device as a display unit. Here, an example of a mobile phone is shown in a perspective view, and reference numeral 1000 denotes a main body of the mobile phone, and reference numeral 1001 denotes a display portion using the above-mentioned organic EL device 1 . In such an electronic device including the organic EL device of the present embodiment as a display means, good light emission characteristics can be obtained.

Claims (7)

1. the manufacture method of a colour filtering chip basic board, this colour filtering chip basic board possesses a plurality of multi-color coloring layers with predetermined pattern, it is characterized in that, comprising:

The wall part that forms the 1st wall part and the 2nd wall part on substrate forms operation, wherein the 1st wall part possesses the 1st peristome in the formation zone that constitutes described dyed layer, the 2nd wall part is positioned on the 1st wall part, and possesses the 2nd peristome in the formation zone that constitutes described dyed layer equally; With

In each peristome of described each wall part, utilize drop ejection method to be ejected in the ejection operation of dissolving or be dispersed with the aqueous body of each coloured material that constitutes described dyed layer in the solvent,

Wherein, described aqueous body is the aqueous body that dyed layer of all kinds is had different viscosities respectively,

Form in the operation at described wall part, to form described the 1st wall part from the outstanding shape of the opening inner face of described the 2nd wall part, in the peristome of the aqueous body that sprays relatively low viscosity, make the central surface area of described the 1st wall part less relatively from the outstanding part of the 2nd wall part, on the other hand, in the peristome of the aqueous body that sprays relative viscosity higher, make the central surface area of described the 1st wall part relatively large from the outstanding part of the 2nd wall part.

2. the manufacture method of an electro-optical device, this electro-optical device possesses a plurality of multiple electro-optic layer with predetermined pattern, it is characterized in that, comprising:

The wall part that forms the 1st wall part and the 2nd wall part on substrate forms operation, wherein the 1st wall part possesses the 1st peristome in the formation zone that constitutes described electro-optic layer, the 2nd wall part is positioned on the 1st wall part, and possesses the 2nd peristome in the formation zone that constitutes described electro-optic layer equally; With

In each peristome of described each wall part, utilize drop ejection method to be ejected in the ejection operation of dissolving or be dispersed with the aqueous body of each functional material that constitutes described electro-optic layer in the solvent,

Wherein, described aqueous body is the aqueous body that various electro-optic layer is had different viscosities respectively,

Form in the operation at described wall part, to form described the 1st wall part from the outstanding shape of the opening inner face of described the 2nd wall part, in the peristome of the aqueous body that sprays relatively low viscosity, make the central surface area of described the 1st wall part less relatively from the outstanding part of the 2nd wall part, on the other hand, in the peristome of the aqueous body that sprays relative viscosity higher, make the central surface area of described the 1st wall part relatively large from the outstanding part of the 2nd wall part.

3. the manufacture method of electro-optical device according to claim 2, it is characterized in that, form in the operation at described wall part, in the peristome of the aqueous body that sprays relatively low viscosity, make from the outstanding length of outstanding described the 1st wall part of the opening inner face of described the 2nd wall part less relatively, on the other hand, in the peristome of the aqueous body that sprays relative viscosity higher, make from the outstanding length of outstanding described the 1st wall part of described the 2nd wall part relatively large.

4. according to the manufacture method of claim 2 or 3 described electro-optical devices, it is characterized in that solvent contained in the described aqueous body all is same solvent or the mixed solvent that contains this same solvent for various electro-optic layer.

5. according to the manufacture method of claim 2 or 3 described electro-optical devices, it is characterized in that, comprise drying process, after described ejection operation, make the aqueous body that is sprayed dry simultaneously respectively in various electro-optic layer.

6. electro-optical device, it is characterized in that, use any described manufacture method manufacturing in the claim 2 to 5, this electro-optical device possesses a plurality of multiple electro-optic layer with predetermined pattern, on substrate, has the wall part that forms by the 1st wall part and the 2nd wall part, wherein the 1st wall part possesses the 1st peristome in the formation zone that constitutes described electro-optic layer, and the 2nd wall part is positioned on the 1st wall part, and possesses the 2nd peristome in the formation zone that constitutes described electro-optic layer equally;

In each peristome of described each wall part, utilize drop ejection method to be ejected in the aqueous body that dissolves or be dispersed with each functional material that constitutes described electro-optic layer in the solvent, described aqueous body is the aqueous body that various electro-optic layer is had different viscosities respectively,

To form described the 1st wall part from the outstanding shape of the opening inner face of described the 2nd wall part, in the peristome of the aqueous body that sprays relatively low viscosity, make the central surface area of described the 1st wall part less relatively from the outstanding part of the 2nd wall part, on the other hand, in the peristome of the aqueous body that sprays relative viscosity higher, make the central surface area of described the 1st wall part relatively large from the outstanding part of the 2nd wall part.

7. an electronic equipment is characterized in that, possesses the described electro-optical device of claim 6.

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