JP2008243406A - Electro-optical device and manufacturing method of electro-optical device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electro-optical device in which barrier ribs to regulate a membrane forming region can be formed with high precision and provide its manufacturing method. <P>SOLUTION: For manufacturing an electro-optical device, after barrier ribs 112 are formed, a liquid composition is coated on an inner side of the barrier ribs 112 and dried and a hole injection-transport layer of a light emitting element and a light emitting layer are formed. When these barrier ribs 112 are formed, after a resin layer of acrylic resin and polyamide resin for forming a first barrier rib layer 112a is formed, a second barrier rib layer 112b composed of fluorine acrylic resin and fluorine polyamide resin is formed on a upper layer of the resin layer, and the second barrier rib layer 112b is masked and undergoes a dry-etching, and the first barrier rib layer 112a is formed on a lower layer side of the second barrier rib layer 112b. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an electro-optical device including a substrate having a thin film formed in a region surrounded by a partition wall, and a method for manufacturing the same.

  In recent years, a light emitting material such as an organic fluorescent material is used as a liquid composition, and a method of patterning the light emitting material by ejecting the liquid composition onto a substrate by an ink jet method is employed between the anode and the cathode. An organic EL (electroluminescence) device having a structure in which a light emitting layer made of the light emitting material is sandwiched has been developed. Such an organic EL device is, for example, a line head of an image forming apparatus such as a copying machine or a display device. It is used as an electro-optical device.

Further, when discharging the liquid composition, as shown in FIG. 6A, the substrate 2 is surrounded by a partition 112z called a bank, and the partition 112z is made of SiO2 so that the liquid composition does not protrude from a predetermined region. _2. A technology in which a hydrophilic first partition layer 112x made of an inorganic compound such as TiO ₂ and a water-repellent second partition layer 112y made of an organic compound such as an acrylic resin or a polyimide resin are laminated. It has been proposed (see Patent Document 1).
JP 2003-249375 A

  In recent years, pixel miniaturization has progressed in display devices and the like, and in order to cope with such miniaturization, it is necessary to further improve the accuracy of the application region (thin film formation region) of the liquid composition. It is also necessary to improve the accuracy of the shape of 112z. However, conventionally, when the first partition layer 112x is formed, after forming the inorganic compound layer, a mask is formed using a photolithography technique, and then etching is performed. Therefore, there is a problem that the first partition layer 112x cannot be formed with high accuracy.

  In the partition 112z, it is preferable that the side wall of the first partition layer 112x and the side wall of the second partition layer 112y form a continuous surface. After forming the inorganic compound layer for forming the partition wall layer 112x, the second partition wall layer 112y is formed, and then the inorganic compound layer is patterned by dry etching using the second partition wall layer 112y as a mask. Should be good. However, since the second partition layer 112y is made of resin, there is an excessive difference in the etching rate during the dry etching between the second partition layer 112y and the inorganic compound layer constituting the first partition layer 112x. 6B, there is a problem that the first partition layer 112x has an overhang structure formed at a position where the first partition layer 112x is retracted from the side wall of the second partition layer 112y.

Further, in order to impart water repellency to the second partition layer 112y, plasma treatment is often performed using CF ₄ gas. However, the plasma treatment varies depending on the size of the substrate 2 or the condition of the wiring and the degree of plasma generation. As a result, there is a problem that the wettability of the substrate 2 varies and unevenness of the film thickness occurs. In addition, when plasma processing is performed using CF ₄ gas, there is a problem that a part of the bank is etched and particles generated thereby adhere to the substrate.

  In view of the above problems, an object of the present invention is to provide an electro-optical device capable of forming a partition defining a thin film formation range with high accuracy, and a method for manufacturing the same.

It is another object of the present invention to provide an electro-optical device capable of imparting water repellency to the second partition layer without performing plasma treatment using CF ₄ gas, and a method for manufacturing the same. .

  In order to solve the above-described problem, the present invention provides an electro-optical device including a substrate in which a thin film is formed in a region surrounded by a partition wall in which a second partition layer is stacked on a first partition layer. The first partition layer is formed of a first resin material, and the second partition layer is formed of a second resin material having higher water repellency than the first resin material. To do.

In the present invention, both the first partition layer and the second partition layer constituting the partition are made of a resin material. For this reason, in the present invention, since the following manufacturing method can be applied, both the first partition layer and the second partition layer can be formed with high accuracy such as shape. Further, the second partition layer is formed of a second resin material having higher water repellency than the first resin material, and the resin material itself has water repellency. For this reason, even if the plasma treatment is not performed using the CF ₄ gas, the second partition wall layer has water repellency, so that problems such as variations in wettability of the substrate due to the plasma treatment do not occur.

  According to the present invention, in the method of manufacturing an electro-optical device including a substrate in which a thin film is formed in a region surrounded by a partition wall in which a second partition layer is stacked on a first partition layer, A first partition wall resin layer forming step of forming a resin layer for forming the partition wall layer, and a resin material having a higher water repellency than the resin layer by providing a second partition wall layer having a predetermined pattern on the resin layer And forming the first partition layer on the lower layer side of the second partition layer by patterning the resin layer using the second partition layer as a mask. 1 partition wall layer forming step, and a liquid material disposing step of disposing a liquid material for forming a thin film in a region surrounded by the partition wall.

  In another aspect of the present invention, in a method of manufacturing an electro-optical device including a substrate in which a thin film is formed in a region surrounded by a partition wall in which a second partition layer is stacked on a first partition layer. After the first resin material is applied, the first partition material layer is formed by exposing and developing to form the first partition wall layer, and the first resin material is formed on the first partition wall layer. A second partition layer forming step of applying a second resin material having low hydrophilicity, and then exposing and developing to laminate the second partition layer on top of the first partition layer; A liquid material disposing step of disposing a liquid material for forming a thin film in the region.

  In the present invention, the second resin material is preferably a fluorine-containing resin material, for example.

  In the present invention, it is preferable that the side wall of the first partition wall layer and the side wall of the second partition wall layer form a continuous surface.

  In the present invention, the thin film is a functional layer including at least an organic light emitting layer. In this case, a first electrode is formed on the lower layer side of the thin film, and a second electrode is formed on the upper layer side of the functional layer. Will be.

  In this invention, it is preferable to have a hydrophilic treatment process for improving the hydrophilicity of the said 1st partition layer. In this case, in the hydrophilic treatment step, for example, oxygen plasma treatment or UV ozone treatment is performed.

  The electro-optical device according to the present invention is used in an electronic apparatus such as a line head of an image forming apparatus such as a copying machine or a display device.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is applied to an electro-optical device in which a thin film is formed independently for each thin film formation region over the entire area of the plurality of thin film formation regions. An example in which the present invention is applied to the case of forming a light emitting element (functional layer (hole injection / transport layer and light emitting layer) of an organic EL element) will be described. Therefore, the scale of each layer and each member is different from the actual one.

[Embodiment 1]
(Electrical configuration)
FIG. 1 is a block diagram showing an electrical configuration of an active matrix organic EL display device as an example of an electro-optical device to which the present invention is applied. The electro-optical device 1 illustrated in FIG. 1 includes a plurality of scanning lines 101, a plurality of signal lines 102 extending in a direction intersecting the scanning lines 101, and a plurality of power supply lines 103 extending in parallel to the signal lines 102. In addition to having a wired configuration, a pixel region 100 is provided near each intersection of the scanning line 101 and the signal line 102. A data side driving circuit 104 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 102, and a scanning side driving circuit 105 including a shift register and a level shifter is connected to the scanning line 101. Each pixel region 100 holds a switching thin film transistor 122 to which a scanning signal is supplied to the gate electrode via the scanning line 101, and a pixel signal supplied from the signal line 102 via the switching thin film transistor 122. The storage capacitor 7, the driving thin film transistor 123 to which the pixel signal held by the storage capacitor 7 is supplied to the gate electrode, and the power supply line 103 through the driving thin film transistor 123. A pixel electrode 111 (anode / first electrode) through which a drive current flows from the power supply line 103 and a functional layer 110 sandwiched between the pixel electrode 111 and the cathode 12 (second electrode) are provided. . Here, the pixel electrode 111, the functional layer 110, and the cathode 12 constitute a light emitting element 5 made of an organic EL element.

  According to such a configuration, when the scanning line 101 is driven and the switching thin film transistor 122 is turned on, the potential of the signal line 102 at that time is held in the holding capacitor 7, and the holding capacitor 7 is driven according to the state. The on / off state of the thin film transistor 123 is determined. Then, current flows from the power supply line 103 to the pixel electrode 111 through the channel of the driving thin film transistor 123, and further current flows to the cathode 12 through the functional layer 110. As a result, the functional layer 110 emits light according to the amount of current flowing through it.

(Configuration of each pixel area)
2A and 2B are a cross-sectional view of the electro-optical device according to Embodiment 1 of the present invention and an enlarged cross-sectional view showing the periphery of the partition wall. Since the basic structure of the organic EL device is well known, detailed description thereof is omitted, but the cross-sectional structure of the electro-optical device 1 of the present embodiment is generally expressed as shown in FIG. FIG. 2A shows a pixel region 100 for three colors of red (R), green (G), and blue (B), and a pixel driving circuit is formed on the substrate 2 by a thin film transistor or the like. The circuit element unit 14, the pixel electrode 111 made of an ITO film, the light emitting element unit 11 including the functional layer 110, and the cathode 12 are sequentially stacked. On the surface side of the cathode 12, a sealing portion is constituted by a sealing resin, a sealing substrate, a sealing can, and the like, but the illustration thereof is omitted because it is not directly related to the present invention.

  In the electro-optical device 1 of the present embodiment, the cathode 12 is made of a reflective material such as Al (aluminum), and light emitted from the functional layer 110 toward the substrate 2 passes through the circuit element unit 14 and the substrate 2. Light emitted to the lower side (observer side) of the substrate 2 and emitted from the functional layer 110 to the opposite side of the substrate 2 is reflected by the cathode 12 and passes through the circuit element unit 14 and the substrate 2 to be transmitted to the substrate 2. It is emitted to the lower side (observer side). If a transparent material such as ITO, Pt, Ir, Ni, or Pd is used as the cathode 12 and a reflective layer is formed on the lower layer side of the pixel electrode 111, light can be emitted from the cathode 12 side. .

  Hereinafter, the structure of each part is demonstrated concretely. First, in the circuit element portion 14, a base protective film 2c made of a silicon oxide film is formed on the substrate 2, and an island-shaped semiconductor film 141 made of polycrystalline silicon is formed on the base protective film 2c. In the semiconductor film 141, a source region 141a and a drain region 141b are formed by high concentration P (phosphorus) ion implantation, and a portion where P is not introduced becomes a channel region 141c. Further, a transparent gate insulating film 142 covering the base protective film 2c and the semiconductor film 141 is formed in the circuit element portion 14, and a gate electrode made of Al, Mo, Ta, Ti, W, or the like is formed on the gate insulating film 142. 143 (scanning line 101) is formed, and a transparent first interlayer insulating film 144a and a second interlayer insulating film 144b are formed on the gate electrode 143 and the gate insulating film 142. The gate electrode 143 is formed at a position corresponding to the channel region 141c of the semiconductor film 141. In addition, contact holes 145 and 146 are formed in the interlayer insulating films 144a and 144b so as to penetrate through these insulating films and are connected to the source and drain regions 141a and 141b of the semiconductor film 141, respectively.

  A transparent pixel electrode 111 made of ITO or the like is patterned and formed in a predetermined shape on the second interlayer insulating film 144b. One contact hole 145 is connected to the pixel electrode 111, and the other contact hole 146 is a power source. Connected to line 103. In this way, the driving thin film transistor 123 connected to each pixel electrode 111 is formed in the circuit element unit 14. The circuit element unit 14 is also formed with the storage capacitor 7 and the switching thin film transistor 122 described above, but these are not shown in FIG.

  Next, in the light emitting element portion 11, a bank-shaped partition wall 112 formed between the functional layers 110 stacked on the upper layers of the plurality of pixel electrodes 111 and surrounding each functional layer 110. And are configured. In this embodiment, the functional layer 110 corresponds to the thin film in the present invention, and the region surrounded by the partition 112 corresponds to the thin film formation region in the present invention.

  A cathode 12 is formed on the functional layer 110, and the light emitting element 5 is configured by the pixel electrode 111, the functional layer 110, and the cathode 12.

  The functional layer 110 includes, for example, a hole injection / transport layer 110a stacked on the pixel electrode 111 and a light emitting layer 110b stacked on the hole injection / transport layer 110a. In addition, other functional layers having other functions, for example, an interlayer layer or an electron transport layer may be formed adjacent to the light emitting layer 110b. The hole injection / transport layer 110a has a function of injecting holes into the light emitting layer 110b and a function of transporting holes inside the hole injection / transport layer 110a. In the light emitting layer 110b, the holes injected from the hole injecting / transporting layer 110a and the electrons injected from the cathode 12 are recombined in the light emitting layer to emit light. Here, the light emitting layer 110b includes, for each color corresponding to each pixel, a red light emitting layer that emits red (R), a green light emitting layer that emits green (G), and a blue light emitting layer that emits blue (B). It is formed as.

  The hole injecting / transporting layer 110a is formed by discharging a liquid composition containing a hole injecting / transporting layer forming material and a polar solvent into the partition 112 and removing the polar solvent, as will be described later. It is. The light emitting layer 110b is also formed by discharging a liquid composition containing a light emitting layer forming material and a polar solvent into the partition 112 and then removing the polar solvent.

  The cathode 12 is formed on the entire surface of the light emitting element portion 11 and plays a role of flowing a current through the functional layer 110 in a pair with the pixel electrode 111. For example, the cathode 12 is formed by laminating a calcium layer and an aluminum layer. At this time, it is preferable to provide a cathode having a low work function on the cathode near the light emitting layer, and in this embodiment, in particular, it plays a role of injecting electrons into the light emitting layer 110b in direct contact with the light emitting layer 110b. Depending on the material of the light emitting layer 110b, LiF may be formed between the light emitting layer 110b and the cathode 12 for the purpose of increasing the light emission efficiency. Here, the aluminum that forms the cathode 12 reflects light emitted from the light emitting layer 110b toward the substrate 2, and an Ag film, a laminated film of Al and Ag, or the like can be used in addition to the Al film.

(Structure of the partition wall)
As shown in FIGS. 2 (a) and 2 (b), the partition 112 defines a range in which a liquid composition for forming the hole injection / transport layer 110a and the light emitting layer 110b is applied. The first partition layer 112a located on the lower layer side (substrate 2 side) and the second partition layer 112b stacked on the first partition layer 112a.

  In such a partition 112, the first partition layer 112a has a thickness in the range of, for example, 50 to 200 nm. The first partition layer 112a has high hydrophilicity and a small contact angle with water. Therefore, the first partition layer 112a is lyophilic with respect to the liquid composition for forming the hole injection / transport layer 110a and the light emitting layer 110b. Such a hydrophilic first partition layer 112a can be realized by being made of a first resin material such as an acrylic resin or a polyimide resin.

On the other hand, the second partition layer 112b has a thickness in the range of, for example, 0.1 to 3.5 μm, and is thicker than the first partition layer 112a. Further, the second partition layer 112b has a lower hydrophilicity and a larger contact angle with water than the first partition layer 112a. Therefore, the second partition layer 112b has liquid repellency with respect to the liquid composition for forming the hole injection / transport layer 110a and the light emitting layer 110b. In forming this water-repellent second partition layer 112b, in this embodiment, it is realized by using a fluorine-containing resin material (second resin material) such as a fluorine-containing acrylic resin or a fluorine-containing polyimide resin. Yes. Such a fluorine-containing resin has a fluorine bond, and the resin itself has water repellency. Therefore, in this embodiment, the second partition layer 112b is not subjected to plasma treatment using CF ₄ gas.

  In this embodiment, the side wall 112c of the first partition wall layer 112a and the side wall 112d of the second partition wall layer 112b are flush with each other and form a continuous surface.

(Method of manufacturing electro-optical device 1)
A method of manufacturing the electro-optical device 1 according to this embodiment will be described with reference to FIGS. 3 and 4 are process cross-sectional views illustrating the manufacturing process of the electro-optical device 1 of the present embodiment.

In manufacturing the electro-optical device 1 of the present embodiment, after forming the circuit element portion 14, the following steps ST11: partition forming step ST12: lyophobic step ST13: hole injection / transport layer forming solution applying step ST14: positive Hole injection / transport layer fixing step ST15: Light emitting layer forming liquid coating step ST16: A light emitting layer fixing step is performed. In addition, a manufacturing method is not restricted to this, When other processes are removed as needed, it may be added.

  Hereinafter, the respective steps will be described with reference to FIGS. 3 and 4 as well. In the partition formation step ST11 shown in FIGS. 3A to 3C, first, as shown in FIG. 3A, in the first partition resin layer formation step, the first partition is formed on the entire surface of the substrate 2. A resin layer 112e such as an acrylic resin or a polyimide resin for forming the layer 112a is applied by a spin coat method or the like and then baked.

  Next, as shown in FIG. 3B, in the second partition layer forming step, a second partition layer 112b made of a fluorine-containing resin is formed in a predetermined pattern on the resin layer 112e. More specifically, a photosensitive resin is used as the fluorine-containing resin, a fluorine-containing resin material (fluorine-containing acrylic resin material or fluorine-containing polyimide resin material) is applied to the upper layer of the resin layer 112e, and then exposed and developed. Two partition wall layers 112b are formed in a predetermined pattern. Here, the thickness of the second partition layer 112b is preferably in the range of 0.1 to 3.5 μm, and particularly preferably about 2 μm. If the thickness is less than 0.1 μm, the second partition layer 112b is thinner than the total thickness of the hole injection / transport layer and the light emitting layer, which will be described later, and the light emitting layer 110b overflows. On the other hand, when the thickness exceeds 3.5 μm, step coverage of the cathode 12 cannot be secured, which is not preferable. Further, if the thickness of the second partition layer 112b is 2 μm or more, the insulation between the cathode 12 and the driving thin film transistor 123 can be increased.

  Next, in the first partition layer forming step, the resin layer 112e is patterned using the second partition layer 112b as a mask, and on the lower layer side of the second partition layer 112b as shown in FIG. A first partition layer 112a is formed. More specifically, dry etching is performed on the resin layer 112e using the second partition layer 112b as a mask to form the first partition layer 112a on the lower layer side of the second partition layer 112b. At that time, since the resin layer 112e (first partition layer 112a) and the second partition layer 112b are both resin materials, the etching rates are equal. Therefore, the side wall 112c of the first partition wall layer 112a and the side wall 112d of the second partition wall layer 112b are flush with each other and form a continuous surface.

  Next, in the hole injection / transport layer forming liquid application step ST13 shown in FIG. 4A, for example, while the inkjet head H1 and the substrate 2 are relatively moved, the positive injection is performed from the plurality of nozzles H2 of the inkjet head H1. A liquid composition containing the hole injection / transport layer forming material is discharged onto the pixel electrode 111. Here, a partition 112 is formed around the pixel electrode 111, and the droplet 110 c ejected from the nozzle H 2 of the inkjet head H 1 lands on a region surrounded by the partition 112 and spreads on the pixel electrode 111. . At that time, even if the droplet 110c is deviated from the predetermined discharge position and discharged onto the upper surface 112f of the partition wall 112, the upper surface 112f has liquid repellency, so that the droplet 110c does not get wet and is repelled. The dropped droplet 110c rolls into the partition 112. Here, as the liquid composition, 3,4-polyethylenediosithiophene / polystyrene sulfonic acid (PEDOT / PSS) which is a polyolefin derivative, polyphenylene vinylene whose polymer precursor is polytetrahydrothiophenylphenylene, 1,1- A composition in which a hole injection / transport layer forming material such as bis- (4-N, N-ditolylaminophenyl) cyclohexane or the like is dissolved in a polar solvent can be used. Examples of the polar solvent include glycol ethers such as isopropyl alcohol, normal butanol, γ-butyrolactone, N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone and derivatives thereof, carbitol acetate, and butyl carbitol acetate. And the like. The hole injection / transport layer forming material may be the same material for each pixel of red (R), green (G), and blue (B), and the composition may be changed for each pixel.

  Next, a hole injection / transport layer fixing step ST14 shown in FIG. 4B is performed. For this purpose, the discharged liquid composition is heated and dried, the polar solvent contained in the liquid composition is evaporated, and the hole injection / transport layer 110a is fixed. The fixing process is performed, for example, in a nitrogen atmosphere at room temperature and a pressure of, for example, about 133.3 Pa (1 Torr). If the pressure is too low, the droplet 110c will boil, which is not preferable. On the other hand, if 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, it is preferable to completely remove the polar solvent and water remaining in the hole injecting / transporting layer 110a by performing a heat treatment in nitrogen, preferably in vacuum, at 200 ° C. for about 10 minutes. .

  Next, the light emitting layer 110b is formed, but before that, a surface modification step may be performed on the hole injection / transport layer 110a. In the light emitting layer forming step ST15, in order to prevent re-dissolution of the hole injecting / transporting layer 110a, as a solvent for the liquid composition used for forming the light emitting layer, a non-soluble insoluble in the hole injecting / transporting layer 110a. A polar solvent is used. On the other hand, since the hole injection / transport layer 110a has low affinity for the nonpolar solvent, the hole injection / transport layer 110a can be ejected onto the hole injection / transport layer 110a even if a liquid composition containing the nonpolar solvent is discharged onto the hole injection / transport layer 110a. There is a possibility that the transport layer 110a and the light emitting layer 110b cannot be adhered to each other or the light emitting layer 110b cannot be uniformly applied. Therefore, before the light emitting layer forming step ST15, a surface modifier made of the same solvent as the non-polar solvent of the liquid composition used when forming the light emitting layer 110b or a similar solvent, such as cyclohexylbenzene, Hydrobenzofuran, trimethylbenzene, tetramethylbenzene, toluene, xylene, or a mixture thereof is applied onto the hole injection / transport layer 110a by the ink jet method (droplet discharge method), spin coating method, or dipping method, and then dried. . By performing such a surface modification step, the surface of the hole injection / transport layer 110a is easily adapted to the nonpolar solvent. In the subsequent step, the liquid composition containing the light emitting layer forming material is injected with the hole injection / transport layer 110a. It can be uniformly applied to the transport layer 110a. Note that a composition in which a hole transporting material is dissolved in the surface modifying material may be applied onto the hole injection / transport layer 110a by an inkjet method and dried.

  Next, in the light emitting layer forming step ST15 shown in FIG. 4C, for example, a liquid containing the light emitting layer forming material from the plurality of nozzles H6 of the ink jet head H5 while relatively moving the ink jet head H5 and the substrate 2. The composition is discharged onto the hole injection / transport layer 110a. At that time, as the liquid composition for forming the light emitting layer, a liquid composition having a composition corresponding to the color corresponding to each pixel is discharged. Here, a partition 112 is formed around the hole injecting / transporting layer 110a, and the droplet 110e discharged from the nozzle H6 of the inkjet head H5 lands on the region surrounded by the partition 112, and the hole Spreads on the injection / transport layer 110a. At this time, even if the droplet 110e is deviated from the predetermined ejection position and ejected onto the upper surface 112f of the partition wall 112, the upper surface 112f has liquid repellency, so that the droplet 110e is not wetted and repelled. The dropped droplet 110e rolls into the partition 112.

  Examples of such a liquid composition include polyfluorene derivatives, polyphenylene derivatives, polyvinyl carbazole, polythiophene derivatives, or polymer materials such as perylene dyes, coumarin dyes, rhodamine dyes such as rubrene, perylene, 9, 10 -The thing which mix | blended the light emitting layer forming material doped with diphenylanthracene, tetraphenyl butadiene, Nile red, coumarin 6, quinacridone etc. in the nonpolar solvent is used. As a light-emitting layer forming material, a π-conjugated polymer material in which double-bonded π electrons are non-polarized on a polymer chain is also a conductive polymer, so that it has excellent light-emitting performance and is therefore preferably used. . In particular, a compound having a fluorene skeleton in the molecule, that is, a polyfluorene compound is more preferably used. In addition to such materials, for example, a composition for an organic EL device disclosed in JP-A-11-40358, that is, a precursor of a conjugated polymer organic compound, and at least one kind for changing light emission characteristics A composition for an organic EL device comprising the above fluorescent dye can also be used as a light emitting layer forming material. The nonpolar solvent is preferably insoluble in the hole injecting / transporting layer 110a. For example, cyclohexylbenzene, dihydrobenzofuran, trimethylbenzene, tetramethylbenzene, or the like can be used. By using such a nonpolar solvent for the liquid composition for forming the light emitting layer, the liquid composition for forming the light emitting layer can be applied without re-dissolving the hole injection / transport layer 110a.

  Next, the light emitting layer fixing step shown in FIG. For this purpose, the discharged liquid composition is heated and dried to evaporate the nonpolar solvent contained in the liquid composition, thereby fixing the light emitting layer 110b. The fixing process is performed, for example, in a nitrogen atmosphere at room temperature at a pressure of about 133.3 Pa (1 Torr) for 5 to 10 minutes. If the pressure is too low, the liquid composition will be bumped, which is not preferable. Further, when the temperature is set to room temperature or higher, the evaporation rate of the nonpolar solvent is increased, and a large amount of the light emitting layer forming material adheres to the wall surface of the partition 112, which is not preferable. Examples of other drying means include a far-infrared irradiation method and a high-temperature nitrogen gas spraying method.

  After the hole injection / transport layer 110a and the light emitting layer 110b are formed on the pixel electrode 111 in this manner, the illustration of the light emitting layer 110b and the second partition wall layer 112b is omitted in the counter electrode forming step, although illustration is omitted. After the cathode 12 (counter electrode) is formed on the entire surface, the surface of the cathode 12 is covered with a sealing resin, a sealing substrate, a sealing can, or the like.

(Main effects of this form)
As described above, in this embodiment, since the second partition layer 112b has liquid repellency, the liquid composition for forming the hole injection / transport layer and the liquid composition for forming the light emitting layer are used as the partition 112. When the liquid composition is applied to the inside of the film, the liquid composition does not get over the partition 112 and protrude into an adjacent region. Therefore, even when the region surrounded by the partition 112 is narrow, the liquid composition can be applied accurately.

  Further, the first partition layer 112a is formed on the lower layer side of the second partition layer 112b by dry etching the resin layer 112e using the second partition layer 112b made of a resin material as a mask. The side wall 112c of the partition wall layer 112a and the side wall 112d of the second partition wall layer 112b are in a flush state and there is no extra step. Therefore, since the hole injecting / transporting layer 110a and the light emitting layer 110b can be formed flat on the pixel electrode 111, even when the light emitting element 5 (organic EL element) is miniaturized, the light emitting characteristics of the light emitting element 5 are obtained. And reliability can be improved.

[Embodiment 2]
5A and 5B are a cross-sectional view of the electro-optical device according to the second embodiment of the present invention and a cross-sectional view showing the periphery of the partition wall in an enlarged manner. Since the basic configuration of the present embodiment is the same as that of the first embodiment, common portions are denoted by the same reference numerals and description thereof is omitted.

  As shown in FIGS. 5 (a) and 5 (b), in this embodiment as well, the liquid composition for forming the hole injection / transport layer 110a and the light emitting layer 110b on the substrate 2 is the same as in the first embodiment. A partition wall 112 is defined to define a region to be coated, and the partition wall 112 is laminated on a first partition layer 112a located on a lower layer side (substrate 2 side) and an upper layer of the first partition layer 112a. And a second partition layer 112b. In such a partition 112, the first partition layer 112a is made of a first resin material such as acrylic resin or polyimide resin, and has high hydrophilicity. In contrast, the second partition layer 112b is made of a fluorine-containing resin material (second resin material) such as a fluorine-containing acrylic resin or a fluorine-containing polyimide resin, and is more hydrophilic than the first partition layer 112a. Is low. Here, the side wall 112c of the first partition wall layer 112a protrudes from the side wall 112d of the second partition wall layer 112b.

  In forming the partition 112 having such a configuration, first, a first resin material such as acrylic resin or polyimide resin is applied, and then exposed and developed to form the first partition layer 112a. A layer forming step is performed. Next, a second resin material such as a fluorine-containing acrylic resin or a fluorine-containing polyimide resin having a lower hydrophilicity than the first resin material is applied to the upper layer of the first partition wall layer 112a, and then exposed and developed. A second partition layer forming process is performed in which the second partition layer 112b is stacked on the upper partition layer 112a.

  After the partition 112 is formed in this manner, as described with reference to FIG. 4, the liquid composition for forming the hole injection / transport layer and the light emitting layer forming are formed in the region surrounded by the partition 112. The liquid arrangement | positioning process of apply | coating the liquid composition of this is performed.

  Even in such a manufacturing method, since the inorganic compound is not etched when the partition 112 is formed, the shape accuracy of the partition 112 is not deteriorated due to side etching or the like.

[Other embodiments]
In Embodiment Mode 2, the mask pattern is different between the exposure mask for forming the first partition layer 112a and the exposure mask for forming the second partition layer 112b. The side wall 112c of the partition wall layer 112a is configured to protrude from the side wall 112d of the second partition wall layer 112b. However, an exposure mask for forming the first partition wall layer 112a and the second partition wall layer 112b are provided. In the exposure mask used to form the barrier rib 112, the side wall 112c of the first barrier rib layer 112a and the side wall 112d of the second barrier rib layer 112b are flush with each other in the same mask pattern. May be.

  In addition, a first resin material for forming the first partition wall layer 112a and a second resin material for forming the second partition wall layer 112b are sequentially applied, collectively exposed and developed, A partition 112 may be formed in which the side wall 112c of the first partition layer 112a and the side wall 112d of the second partition layer 112b are flush with each other.

  Further, after the partition wall 112 is formed, the hydrophilicity of the first partition wall layer 112a is increased by performing a plasma treatment using oxygen as a processing gas, or a hydrophilic treatment process such as UV ozone treatment in contact with ozone under UV irradiation. May be raised. In that case, the second partition layer 112b is also exposed to plasma treatment or UV ozone treatment, but the entire second partition layer 112b is made of a fluorine-containing acrylic resin, a fluorine-containing polyimide resin, or the like. Therefore, the water repellency is not impaired by such treatment.

  In the case of Embodiment Mode 2, the first partition layer 112a is formed, and before the second partition layer 112b is formed, plasma treatment using oxygen as a processing gas or contact with ozone under UV irradiation is performed. A hydrophilization treatment process such as UV ozone treatment may be performed.

  The technical scope of the present invention is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, in the above embodiment, the present invention is applied to form the light emitting element 5 in the organic EL device. However, if the thin film is formed over the entire region surrounded by the partition wall, the color filter is used. It may be applied to form. Such a color filter is used for forming a light emitting element 5 that emits white light and displaying a color image by passing the white light through the color filter in an organic EL device, for example. The color filter is used to display a color image in a liquid crystal device among electro-optical devices, for example. Furthermore, the present invention may be applied when a thin film is formed as a wiring or an electrode by applying and drying a liquid composition.

1 is a block diagram illustrating an electrical configuration of an active matrix organic EL display device as an example of an electro-optical device to which the present invention is applied. FIG. FIG. 2 is a cross-sectional view of the electro-optical device according to the first embodiment of the present invention and a cross-sectional view showing an enlarged periphery of a partition wall. FIG. 6 is a process cross-sectional view illustrating a manufacturing process of the electro-optical device according to the first embodiment of the invention. FIG. 6 is a process cross-sectional view illustrating a manufacturing process of the electro-optical device according to the first embodiment of the invention. FIG. 4 is a cross-sectional view of an electro-optical device according to a second embodiment of the present invention, and a cross-sectional view illustrating an enlarged periphery of a partition wall. It is sectional drawing which expands and shows the conventional partition periphery.

Explanation of symbols

1 .. Electro-optical device, 2 .. Substrate, 5 .. Light emitting element, 12 .. Cathode (second electrode), 100... Pixel region, 110... Functional layer, 110 a. (Functional layer), 110b... Light emitting layer (functional layer), 111... Pixel electrode (first electrode), 112 .. partition wall, 112 a... First partition layer, 112 b. 112c .. Side wall of the first partition layer, 112d .. Side wall of the second partition layer

Claims (8)

In an electro-optical device including a substrate in which a thin film is formed in a region surrounded by a partition wall in which a second partition layer is stacked on a first partition layer.
The first partition layer is formed of a first resin material,
The electro-optical device, wherein the second partition layer is formed of a second resin material having higher water repellency than the first resin material.   The electro-optical device according to claim 1, wherein the second resin material is a fluorine-containing resin material.   The electro-optical device according to claim 1, wherein the side wall of the first partition wall layer and the side wall of the second partition wall layer form a continuous surface. The thin film is a functional layer including at least an organic light emitting layer,
4. The electro-optical device according to claim 1, wherein a first electrode is formed on a lower layer side of the thin film, and a second electrode is formed on an upper layer side of the functional layer. 5. apparatus. In a method of manufacturing an electro-optical device including a substrate in which a thin film is formed in a region surrounded by a partition wall in which a second partition layer is stacked on a first partition layer,
A first partition wall resin layer forming step of forming a resin layer for forming the first partition layer;
A second partition layer forming step of forming a second partition layer having a predetermined pattern on the resin layer with a resin material having higher water repellency than the resin layer;
Patterning the resin layer using the second partition layer as a mask, and forming the first partition layer on the lower layer side of the second partition layer; and
A liquid material disposing step of disposing a liquid material for forming a thin film in a region surrounded by the partition;
A method for manufacturing an electro-optical device. In a method of manufacturing an electro-optical device including a substrate in which a thin film is formed in a region surrounded by a partition wall in which a second partition layer is stacked on a first partition layer,
A first partition layer forming step of applying the first resin material, and then exposing and developing to form the first partition layer;
A second resin material having a lower hydrophilicity than the first resin material is applied to the upper layer of the first partition layer, and then exposed to light and developed to form the second partition layer on the first partition layer. A second partition layer forming step of laminating layers;
A liquid material disposing step of disposing a liquid material for forming a thin film in a region surrounded by the partition;
A method for manufacturing an electro-optical device.   The method of manufacturing an electro-optical device according to claim 5, further comprising a hydrophilic treatment step for increasing the hydrophilicity of the first partition wall layer.   8. The method of manufacturing an electro-optical device according to claim 7, wherein in the hydrophilic treatment step, oxygen plasma treatment or UV ozone treatment is performed.

Images