Patent Publication Number: US-2009220679-A1

Title: Display apparatus, and display apparatus manufacturing method and apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of application Ser. No. 10/716,885 filed Nov. 18, 2003 (abandoned), which is incorporated herein in its entirety by this reference. 
     This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2002-335237, filed Nov. 19, 2002, the entire contents of which are incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a display apparatus having optical elements formed on a substrate, and a display apparatus manufacturing method and apparatus. 
     2. Description of the Related Art 
     An organic EL element has a multilayered structure in which an anode, an EL layer made of an organic compound, and a cathode are stacked in this order. When a positive bias voltage is applied between the anode and the cathode, the EL layer emits light. A plurality of such organic EL elements each serving as a sub pixel that emits red, green, or blue light are arrayed in a matrix on a substrate, thereby implementing an organic EL display panel that displays an image. 
     In an active matrix driving organic EL display panel, one of the anode and cathode can be formed as a common electrode common to all sub pixels. At least the other electrode and EL layer must be patterned for each sub pixel. A conventional semiconductor device manufacturing technique can be applied as a method of patterning an anode or cathode for each sub pixel. That is, an anode or cathode can be patterned for each sub pixel by appropriately executing a film formation step using PVD or CVD, a mask step using photo-lithography, and a thin film shape process step using etching. 
     Jpn. pat. Appln. KOKAI Publication No. 10-12377 and 2000-353594 propose a technique for patterning an EL layer for each sub pixel by using the inkjet technology. In this technique, a material for an EL layer is dissolved in an organic solvent to prepare an organic solution. A droplet of the solution is discharged from a nozzle for each sub pixel, thereby patterning the EL layer for each sub pixel. 
     In this technique for patterning the EL Layer by using the inkjet method, the solvent in which the organic material for the EL layer is dissolved may evaporate at the tip portion of the nozzle that discharges the solution. Since the nozzle may then clog, a defective sub pixel without any EL layer may be formed, or the EL layer thickness in a sub pixel may become nonuniform. 
     When the EL layer should be patterned by the inkjet method, the EL solution must be discharged while aligning the nozzle to each sub pixel position and sequentially scanning the sub pixels. Hence, the time taken to pattern all EL layers in the plane is long. To pattern all EL layers in the plane in a short time, the inkjet apparatus must have a plurality of nozzles so that the organic solution is applied simultaneously from them. In this case, the plurality of nozzles must be arrayed in a single plane in the inkjet apparatus. To provide an organic EL display panel which attains a high resolution by precisely arraying sub pixels, the plurality of nozzles must also be precisely arrayed. The array must be finely designed in accordance with the distance between adjacent sub pixels, resulting in a difficulty. Hence, with film formation using only the inkjet method, it is difficult to precisely pattern the EL layer in a short time. 
     BRIEF SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a display apparatus obtained by efficiently executing precise pixel patterning, and a display apparatus manufacturing method and apparatus. 
     In order to achieve the above object, according to a first aspect of the present invention, there is provided a display apparatus comprising: 
     a substrate; 
     a first electrode and a second electrode which are formed on the substrate; and 
     an optical material layer which is located between the first electrode and the second electrode and formed by bringing a droplet of an optical material containing liquid, that sticks to a predetermined position of a surface of a plate in accordance with a pattern based on a difference in wettability, into contact with the substrate and transferring the droplet to the substrate side. 
     Since the droplet is transferred, the optical material layer can quickly be formed, and a structure suitable for mass production can be obtained. When a partition is formed, the droplet can be surrounded by the partition. Hence, the optical material layer having a predetermined shape can be accurately patterned. Especially when a partition having liquid repellency is used, the droplet can be suppressed from flowing to pixels other than the desired pixel. 
     According to a second aspect of the present invention, there is provided a method of manufacturing a display apparatus including an optical element having an optical material layer between a first electrode and a second electrode which are formed on a substrate, comprising: 
     an aligning step of making the substrate oppose a plate which has a wettability changeable layer and to which a droplet of an optical material containing liquid sticks in accordance with a pattern based on a difference in wettability, and of aligning the substrate and the plate; and 
     a transfer step of bringing the droplet into contact with the substrate to transfer the droplet to the substrate side, thereby forming the optical material layer. 
     According to this method, since films of the optical material containing liquid can be formed simultaneously for a plurality of pixels, the productivity is higher than that of the inkjet method which applies the optical material containing liquid to each pixel. The liquid repellent portion of the wettability changeable layer of the pattern repels the optical material containing liquid. Most of the optical material containing liquid collects at a desired pattern portion. Since the amount of the optical material containing liquid can be a minimum necessary amount, the cost can be reduced. 
     According to a third aspect of the present invention, there is provided a display apparatus manufacturing apparatus for manufacturing a display apparatus including an optical element having an optical material layer between a first electrode and a second electrode which are formed on a substrate, comprising: 
     moving means, having a plate having a wettability changeable layer with a pattern based on a difference in wettability to an optical material containing liquid, for bringing a droplet sticking to the wettability changeable layer into contact with the substrate. 
     According to the present invention, a droplet can be patterned at a desired position of a plate by changing the wettability by irradiating the plate with active rays. Hence, the droplet of the optical material containing liquid can be quickly transferred to the substrate side as compared to the inkjet method. 
     In this specification, an “optical material containing liquid” indicates a liquid containing an organic compound that forms the optical material layer or a precursor thereof. The liquid may be a solution prepared by dissolving an organic compound or a precursor thereof. Alternatively, the liquid may be a dispersion prepared by dispersing an organic compound or a precursor thereof. The liquid may partially contain an inorganic substance. “Active rays” indicate rays that excite a photocatalyst, including visible rays, UV rays, electron beam, and infrared rays. Examples of a “photocatalyst” are titanium oxide, zinc oxide, tin oxide, strontium titanate, tungsten oxide, bismuth oxide, and iron oxide. 
     Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
       The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the general description given above and the detailed description of the embodiments given below, serve to explain the principles of the invention. 
         FIG. 1  is a plan view showing an organic EL display panel according to the first embodiment of the present invention; 
         FIG. 2  is a sectional view of the organic EL display panel shown in  FIG. 1 ; 
         FIGS. 3A to 3D  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 1 ; 
         FIG. 4  is a sectional view showing a step in manufacturing a plate to be used to manufacture the organic EL display panel shown in  FIG. 1 ; 
         FIGS. 5A to 5C  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 1 ; 
         FIGS. 6A to 6C  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 1 ; 
         FIGS. 7A to 7C  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 1  as a modification to the first embodiment; 
         FIG. 8  is a sectional view showing an organic EL display panel according to the second embodiment of the present invention; 
         FIGS. 9A to 9C  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 8 ; 
         FIGS. 10A and 10B  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 8 , 
         FIGS. 11A to 11C  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 8 ; 
         FIG. 12  is a sectional view showing an organic EL display panel according to the third embodiment of the present invention; 
         FIGS. 13A to 13C  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 12 ; 
         FIGS. 14A and 14B  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 12 ; and 
         FIGS. 15A to 15C  are sectional views showing steps in manufacturing the organic EL display panel shown in  FIG. 12 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Detailed embodiments of the present invention will be described below with reference to the accompanying drawing. However, the scope of the invention is not limited to the illustrated examples. In the following description, “when viewed from the upper side” means “when viewed from a direction perpendicular to the planar direction of a transparent substrate  12  (to be described later)”. 
     First Embodiment 
       FIG. 1  is a plan view of an organic EL display panel  10  serving as a display apparatus.  FIG. 2  is a sectional view taken along a line (II)-(II) in  FIG. 1 . 
     In the organic EL display panel  10 , red, green, and blue sub pixels are arrayed in a matrix when viewed from the upper side. The organic EL display panel  10  executes matrix display by an active matrix driving method. More specifically, in the organic EL display panel  10 , each sub pixel is constituted by one-organic EL element  11  and one pixel circuit that drives the organic EL element  11 . A signal is input from a peripheral driver (not shown) to the pixel circuit through a signal line  51  and a scanning line  52 . The pixel circuit turns on/off a current flowing to the organic EL element  11  in accordance with the signal. Alternatively, the pixel circuit holds the current value to keep a predetermined luminance of the organic EL element  11  during its light emission period. The pixel circuit is formed from at least one thin-film transistor per sub pixel. A capacitor and the like are sometimes added as needed. In this embodiment, the pixel circuit is formed from two transistors  21 . Three sub pixels of red, green, and blue are continuously arrayed to form one pixel. 
     The organic EL display panel  10  has a flat transparent substrate  12 . The plurality of scanning lines  52  run in the horizontal direction on one surface  12   a  of the transparent substrate  12 . The scanning lines  52  are arrayed parallel to each other almost at an equal interval when viewed from the upper side. The scanning lines  52  have electrical conductivity. The scanning lines  52  are covered with a gate insulating film  23  formed on the entire surface  12   a  of the transparent substrate  12 . The plurality of signal lines  51  run in the vertical direction on the gate insulating film  23 . The signal lines  51  are perpendicular to the scanning lines  52  when-viewed from the upper side. The signal lines  51  are also arrayed parallel to each other almost at an equal interval when viewed from the upper side. 
     The plurality of transistors  21  are formed on the surface  12   a  of the transparent substrate  12 . Each transistor  21  is formed from a gate electrode  22 , gate insulating film  23 , semiconductor film  24 , impurity-doped semiconductor films  25  and  26 , drain electrode  27 , and source electrode  28 . These components are stacked to form an MOS field effect transistor. The gate insulating film  23  is formed on the entire surface of the transparent substrate  12 . The gate insulating film  23  is common to all the transistors  21 . 
     The transistors  21  are covered with a protective insulating film  18 . The protective insulating film  18  is formed into a mesh pattern along the signal lines  51  and scanning lines  52  when viewed from the upper side. Accordingly, a plurality of surrounded regions  19  surrounded by the protective insulating film  18  are formed as if they were arrayed in a matrix on the transparent substrate  12 . The protective insulating film  18  is made of an inorganic silicide such as silicon oxide (SiO 2 ) or silicon nitride (SiN). 
     A partition  20  is formed on the protective insulating film  18 . The partition  20  is also formed into a mesh pattern when viewed from the upper side, like the protective insulating film  18 . The width of the partition  20  increases toward the transparent substrate  12 . The partition  20  has insulating properties. The partition  20  is made of an organic compound such as a photosensitive resin like polyimide resin, acrylic resin, or novolac resin. A film (e.g., a fluoroplastic film) with a “liquid repellency” may be formed on the surface of the partition  20 . The surface layer of the partition  20  may have liquid repellency. The “liquid repellency” is a surface property in which the surface has a contact angle of more than 40° with an “organic compound containing liquid (liquid which contains an organic compound)”, i.e., an optical material containing liquid. In other words, the liquid repellency is a surface property in which the surface repels the organic compound containing liquid. The “organic compound containing liquid” is a liquid containing an organic compound as the optical material that forms an EL layer  15  ( 15 (R),  15 (G),  15 (B)) which is to be described later or its precursor. The organic compound containing liquid may be a solution prepared by dissolving, as a solute, an organic compound that forms the EL layer  15  or its precursor in a solvent. The organic compound containing liquid may be a dispersion prepared by dispersing an organic compound that forms the EL layer  15  or its precursor in a liquid. The liquid repellency of the partition  20  will be described later in detail in the section “Lyophilic Process and Liquid Repellent Process”. 
     The organic EL element  11  as an optical element will be described next. The organic EL element  10  has a multilayered structure in which an anode  13  ( 13 (R),  13 (G),  13 (B)), the EL layer  15 , and a cathode  16  are stacked in this order from the side of the transparent substrate  12 . The anode  13  has a transparency to visible light and electrical conductivity. The anode  13  is made of a material having a relatively high work function. The anode  13  is made of, e.g., indium oxide, zinc oxide, or tin oxide or a mixture containing at least one of them (e.g., indium tin oxide (ITO) or indium zinc oxide). 
     The anode or anode section  13  is formed in each of regions surrounded by the signal lines  51  and scanning lines  52  when viewed from the upper side. The plurality of anode sections  13  are arrayed in a matrix on the gate insulating film  23  at an interval. 
     Each anode section  13  corresponds to one surrounded region  19  when viewed from the upper side. The area of the surrounded region  19  is smaller than that of the anode  13 . The surrounded region  19  is arranged in the anode  13 . The outer peripheral portion of the anode  13  partially overlaps the protective insulating film  18  and partition  20 . In this example, the anode  13  is connected to the source electrode  28  of the transistor  21 . Alternately, the anode  13  may be connected to another transistor or capacitor depending on the circuit arrangement of the pixel circuit. A film with a “lyophilic effect” may be formed on the surface of the anode  13 . The surface layer of the anode  13  may have a lyophilic effect. The “lyophilic effect” indicates a surface property in which the surface has a contact angle of 40° or less with an organic compound containing liquid, and the organic compound containing liquid is hardly repelled. That is, the lyophilic effect means a surface wets well with the organic compound containing liquid. The lyophilic effect of the anode  13  will be described later in detail in the section “Lyophilic Process and Liquid Repellent Process”. 
     The EL layer  15  is formed on each anode section  13 . The EL layers  15  are arrayed in a matrix when viewed from the upper side and arranged in corresponding surrounded regions  19 . 
     The EL layer  15  is an optical material layer made of a light-emitting material as an organic compound. The EL layer  15  recombines holes injected from the anode  13  and electrons injected from the cathode  16  to generate excitons and emits red, green, or blue light. For example, an EL layer  15  that emits red light, an EL layer  15  that emits green light, and an EL layer  15  that emits blue light are arrayed in the horizontal direction in this order. The color tone of one pixel is defined by the three color EL layers  15 . Throughout the drawings, (R) is added to the EL layer  15  that emits red light. (G) is added to the EL layer  15  that emits green light. (B) is added to the EL layer  15  that emits blue light. (R), (G), or (B) is also added to the anode  13  and surrounded region  19  corresponding to each color. 
     An electron transport substance may be mixed into the EL layer  15 , as needed. A hole transport substance may be mixed into the EL layer  15 , as needed. Both an electron transport substance and a hole transport substance may be mixed into the EL layer  15 , as needed. 
     Each EL layer  15  may have a three-layered structure including a hole transport layer, a light-emitting layer of narrow sense, and an electron transport layer sequentially from the anode  13 . Alternately, each EL layer  15  may have a two-layered structure including a hole transport layer and a light-emitting layer of narrow sense sequentially from the anode  13 . Each EL layer  15  may have a single-layered structure including a light-emitting layer of narrow sense. Alternatively, each EL layer  15  may have a multilayered structure in which an electron or hole injection layer is inserted between appropriate layers in one of the above layer structures. The EL layers  15  are formed by waterless lithography, as will be described later. The hole transport layer, light-emitting layer of narrow sense, and electron transport layer are also layers made of organic compounds. That is, they are optical material layers. 
     The cathode  16  is formed continuously on the entire one side of the transparent substrate  12  to cover all the EL layers  15  and the partition  20 . The cathode  16  opposes the anode  13  in each surrounded region  19 . The cathode  16  contains at least a material having a low work function in the surface that is in contact with the EL layers  15 . More specifically, the cathode  16  is made of a simple substance selected from magnesium, calcium, lithium, barium, and a rare earth, or an alloy containing at least one of these simple substances. The cathode  16  may have a multilayered structure. For example, the cathode  16  may have a multilayered structure in which the surface of a film made of the above-described material with a low work function is covered with a material such as aluminum or chromium that has a high work function and low resistivity. The cathode  16  preferably has a light shielding effect with respect to visible light. The cathode  16  more preferably has a high reflectivity to visible light emitted from the EL layer  15 . That is, since the cathode  16  acts as a mirror surface that reflects visible light, the light utilization efficiency can be increased. 
     As described above, the cathode  16  is a continuous layer common to all sub pixels. The anode  13  and EL layer  15  are separately formed for each sub pixel. 
     A method of manufacturing the organic EL display panel  10  will be described next. 
     The manufacturing method of the organic EL display panel  10  comprises the following steps. 
     (i) Driving Substrate Manufacturing Step: The transistors  21 , anodes  13 , and partition  20  are sequentially formed on the transparent substrate  12 . 
     (ii) Print Step: The EL layers  15  are formed for each color by using a plate of a corresponding color. More specifically, an organic compound-containing liquid containing an organic compound that emits red light is applied to a red plate. The organic compound containing liquid applied to the red plate is transferred to the transparent substrate  12 . With this process, the red EL layers  15 (R) are formed on the red anodes  13 (R). In a similar way, the green EL layers  15 (G) and blue EL layers  15 (B) are also sequentially formed by using green and blue plates. 
     (iii) Electrode Formation Step: The Cathode  16  is Formed. 
     These steps will be described below in detail. 
     First, a “plate making step” is executed as preparation for (i) driving substrate manufacturing step. In the plate making step, a master is prepared for each of red, green, and blue. A red plate, green plate, and blue plate are made from these masters. The red plate is used to pattern the red EL layers  15 (R). The green plate is used to pattern the green EL layers  15 (G). The blue plate is used to pattern the blue EL layers  15 (B). 
     There are two plate making methods. Both the plate making methods use photocatalytic reaction and can be applied to all the red, green, and blue plates. 
     The first plate making method will be described. 
     First, as shown in  FIG. 3A , a wettability changeable layer  202  is formed on a surface  201   a  of a substrate  201  as a flat base material. This is the master for a plate. 
     The wettability changeable layer  202  changes its wettability when irradiated with active rays hν. The wettability changeable layer  202  contains a photocatalyst which causes a change in wettability. As the active rays h ν, rays in any wave range that excites the photocatalyst can be used, including visible rays, UV rays, and infrared rays. 
     Examples of the photocatalytic material used for the wettability changeable layer  202  are metal oxides such as titanium oxide (TiO 2 ), zinc oxide (ZnO), tin oxide (SnO 2 ), strontium titanate (SrTiO 3 ), tungsten oxide (WO 3 ), bismuth oxide (Bi 2 O 3 ), and iron oxide (Fe 2 O 3 ), which are known as optical semiconductors. Especially, titanium oxide is preferably used. Either anatase-type titanium oxide or rutile-type titanium oxide can be used. Anatase-type titanium oxide is more preferably used because the excitation wavelength is 380 nm or less. The amount of the photocatalyst in the photocatalyst containing layer is preferably 5 to 60 wt %, and more preferably, 20 to 40 wt %. 
     The binder that can be used in the wettability changeable layer  202  preferably has a high binding energy so that the principal skeleton does not decompose upon photoexcitation of the photocatalyst. Examples of such a material are (A) organopolysiloxane that exhibits a high strength by hydrolyzing and polycondensing chlorosilane or alkoxysilane by sol-gel reaction and (B) organopolysiloxane crosslinked to reactive silicone that has a high water repellency or oil repellency. 
     In (A), the main component can be one or two or more hydrolytic condensates or hydrolytic co-condensates of a silicide, which are represented by a general formula R 3   n SiR 4   4-n  (n=1 to 3). In this general formula, R 3  can be, e.g., an alkyl group, fluoroalkyl group, vinyl group, amino group, or epoxy group. R 4  can be, e.g., a halogen or a functional group, methoxyl group, ethoxyl group, or acetyl group containing a halogen. Polysiloxane containing a fluoroalkyl group can particularly preferably be used as a binder. More specifically, one or two or more hydrolytic condensates or hydrolytic co-condensates of fluoroalkylsilane can be used. Alternatively, a generally known fluorine-based silane coupling agent may be used. Examples of a fluoroalkyl group are functional groups represented by 
       —(CH 2 ) a (CF 2 ) b CF 3   (1) 
       —(CH 2 ) c (CF 2 ) d CF(CF 3 ) 2   (2) 
     wherein a, b, c, and d are integers (a, b, c, d≧0). 
     An example of the reactive silicone of (B) is a compound having a skeleton represented by 
       —(Si(R 1 )(R 2 )O) n —  (3) 
     wherein n is an integer (n≧2), and R 1  and R 2  can be a substituted or non-substituted alkyl, alkenyl, aryl, or cyanoalkyl group with a carbon number 1 to 10. Preferably, 40 mol % or less of the entire compound can be vinyl, phenyl, or phenyl halide. At least one of R 1  and R 2  is preferably a methyl group because the surface is energy is minimum. More preferably, the content of the methyl group is 60 mol % or more, and at least one reactive group such as a hydroxyl group is present in the molecular chain of the chain terminal or side chain. 
     In addition to organopolysiloxane described above, a stable organo silicide such as dimethyl polysiloxane that causes no crosslinking reaction may be mixed into the binder. 
     The wettability changeable layer  202  can be formed by, e.g., applying a coating liquid containing a photocatalyst to the base material by spray coating, dip coating, roll coating, or bead coating. When a coating liquid containing a photocatalyst is to be used, a solvent that can be used for the coating liquid is not particularly limited. An example of the solvent is an alcohol-based organic solvent such as ethanol or isopropanol. 
     An example of the method of forming the wettability changeable layer  202  will be described in detail. 
     The substrate  201  is cleaned by pure water. A coating liquid (to be referred to as a silazane-based solution hereinafter) prepared by dissolving a silazane compound having a fluoroalkyl group is applied to the surface  201   a  of the substrate  201  by dip coating. A photocatalyst is dispersed in this silazane-based solution. 
     The “silazane compound having a fluoroalkyl group” has an Si—N—Si bond. The fluoroalkyl group is bonded to N and/or Si. An example is a monomer, oligomer, or polymer represented by 
       RfSi(NH) 3/2   (4) 
     wherein Rf is a fluoroalkyl group. 
     An example of the solvent for the silazane-based solution is a fluorine-based solvent. 
     As the silazane compound, a silazane oligomer (KP-801M available from Shin-Etsu Chemical Co., Ltd.) represented by general formula (5) and chemical structure formula (6) is used. In the above-described dip coating step, a silazane-based solution (concentration: 3%) prepared by dissolving the silazane oligomer as a solute in an m-xylene hexafluoride solvent is applied to the substrate  201  by dip coating. 
     
       
         
         
             
             
         
       
     
     Next, an inert gas such as nitrogen gas or argon gas is blown to the substrate  201  to evaporate the solvent of the silazane-based solution. The silazane compound is deposited on the surface  201   a  of the substrate  201 . The solvent may be evaporated by heating. 
     When the substrate  201  is left to stand for 10 to 30 min, the silazane compound hydrolyzes in the presence of water in the atmosphere, and bonds and polymerizes to the surface of the substrate  201 . The wettability changeable layer  202  which contains, as a binder, a condensate having a fluoroalkyl group bonded to a main chain made of silicon and oxygen is formed on the substrate  201 . The condensate contained in the wettability changeable layer  202  is represented by 
     
       
         
         
             
             
         
       
     
     wherein Rf is a fluoroalkyl group having liquid repellency, as described above, and X is the atom of the substrate  201  or an atom chemically adsorbed in the surface of the substrate  201 . When the silazane compound is a silazane oligomer represented by general formula (5), Rf is C 8 F 17 C 2 H 4 . The binder of the wettability changeable layer  202  is a condensate whose side chain contains a functional group containing fluorine. Hence, the wettability changeable layer  202  has a low wettability to an organic compound containing liquid and exhibits liquid repellency. The formed wettability changeable layer  202  contains a photocatalyst. 
     As shown in  FIG. 3B , the wettability changeable layer  202  is partially irradiated with the active rays hν by using a photomask substrate  203 α. A red plate  200 R is thus completed. 
     The photomask substrate  203 α has a flat transparent substrate  204  that passes the active rays hν. A mesh-like mask  205  that hardly passes the active rays hν is formed on a surface  204   a  of the transparent substrate  204 . Since the mask  205  has a mesh pattern, a number of opening portions  205   a  are formed in the mask  205 . The array pattern of the opening portions  205   a  when viewed from the upper side is the same as the array pattern of the surrounded regions  19 (R) corresponding to the pixels that emit red light. 
     The photomask substrate  203 α having the above structure is made to oppose the wettability changeable layer  202 . The wettability changeable layer  202  is irradiated with the active rays hν through the photomask substrate  203 α. The mask  205  of the photomask substrate  203 α shields the active rays hν while the opening portions  205   a  pass the active rays hν. In this way, the active rays hν become incident on the wettability changeable layer  202 . In the lyophilic region  202   a  where the active rays hν are incident, since the active rays hν become incident on the photocatalyst (e.g., titanium oxide), active oxygen species (e.g., .OH) are generated. The active oxygen species desorb the functional group (e.g., Rf) that exhibits liquid repellency and substitutes it with a functional group (e.g., —OH) that exhibits a lyophilic effect. For this reason, in the lyophilic region  202   a  where the active rays hν are incident, the wettability increases, and a lyophilic effect is obtained. Accordingly, a pattern based on a difference in wettability, i.e., a pattern having the lyophilic region  202   a  and a liquid repellent region  202   b  is formed in the wettability changeable layer  202 . 
     The lyophilic regions  202   a  where the active rays hν are incident correspond to the surrounded regions  19 (R) of red light-emitting pixels in the wettability changeable layer  202 . The liquid repellent regions  202   b  where the active rays hν are not incident correspond to the surrounded regions  19 (G) of green light-emitting pixels, the surrounded regions  19 (B) of blue light-emitting pixels, and the partition  20 . Hence, the array pattern of the lyophilic regions  202   a  when viewed from the upper side is the same as the array pattern of the surrounded regions  19 (R) when viewed from the upper side. 
     A green plate  200 G ( FIG. 6A ) and blue plate  200 B ( FIG. 6B ) are also made by partially irradiating masters with the active rays hν, like the red plate  200 R. For the green plate  200 G, the active rays hν are sent onto the wettability changeable layer  202  only in regions corresponding to the green surrounded regions  19 (G) by using a photomask substrate. For the blue plate  200 B, the active rays hν are sent onto the wettability changeable layer  202  only in regions corresponding to the blue surrounded regions  19 (B) by using a photomask substrate. Hence, in the green plate  200 G, the array pattern of the lyophilic regions  202   a  when viewed from the upper side is the same as the array pattern of the surrounded regions  19 (G) when viewed from the upper side. In the blue plate  200 B, the array pattern of the lyophilic regions  202   a  when viewed from the upper side is the same as the array pattern of the surrounded regions  19 (B) when viewed from the upper side. 
     The second plate making method will be described. 
     In the second plate making method, the wettability changeable layer  202  need not contain a photocatalyst. However, as shown in  FIG. 4 , a photomask substrate  203 β is used in place of the photomask substrate  203  α used in the first plate making method. The photomask substrate  203 β has a transparent substrate  204  and mask  205 , like the photomask substrate  203 α. In addition, a photocatalytic film  206  that covers the entire mask  205  is formed on a side of the entire surface  204 α of the transparent substrate  204 . Examples of the photocatalytic material of the photocatalytic film  206  are metal oxides such as titanium oxide (TiO 2 ), zinc oxide (ZnO), tin oxide (SnO 2 ), strontium titanate (SrTiO 3 ), tungsten oxide (WO 3 ), bismuth oxide (Bi 2 O 3 ), and iron oxide (Fe 2 O 3 ). The binder of the photocatalytic film  206  is not particularly limited as long as it has a resistance against the active rays hν. The photocatalytic film  206  may be formed only on a part of the surface  204   a  of the transparent substrate  204 , which is exposed in the opening portions  205   a  of the mask  205 . 
     The photomask substrate  203 β is made to oppose the wettability changeable layer  202 . The opening portions  205   a  are partially irradiated with the active rays hν from the upper side of the photomask substrate  203 β. The photocatalytic film  206  is excited by the active rays hν to generate active oxygen species (.OH). The active oxygen species change the liquid repellency of the opposing lyophilic region  202   a  to the lyophilic effect. Hence, the plate  200 R having a pattern based on the difference between the lyophilic effect and the liquid repellency is completed. The mask  205  shields the active rays hν. The function of the photocatalyst is as follows. When the active rays hν become incident on the photocatalytic film  206 , the active oxygen species are generated. The active oxygen species diffuse the gas phase between the photomask substrate  203 β and the wettability changeable layer  202 . Active oxygen that has arrived at the wettability changeable layer  202  desorbs the functional group that exhibits the liquid repellency in the wettability changeable layer  202  and substitutes the functional group with ones that exhibits a lyophilic effect. 
     The second plate making method can also be applied to make the green plate  200 G and blue plate  200 B. The second plate making method is the same as the first plate making method except that the photocatalytic film  206  is formed on the photomask substrate  203 β. Even in the second plate making method, the wettability changeable layer  202  can also contain a photocatalyst, as in the first plate making method. 
     “(i) Driving Substrate Manufacturing Step” 
     As shown in  FIG. 3C , a film formation step such as PVD or CVD, a mask step such as photolithography, and a thin film shape process step such as etching are appropriately executed to pattern the plurality of scanning lines  52  and gate electrodes  22  arrayed in the row direction. Then, the scanning lines  52  and gate electrodes  22  are covered with the gate insulating film  23  that is formed on the entire surface  12   a  of the transparent substrate  12 . Next, the semiconductor film  24 , and impurity-doped semiconductor films  25  and  26  are formed and patterned to pattern the anode  13  on the surface  12   a  of the transparent substrate  12  in correspondence with each sub pixel. The plurality of signal lines  51  are patterned to be arrayed in the column direction that is perpendicular to the row direction. In addition, the drain electrodes  27  and source electrodes  28  are patterned. The source electrodes  28  of the transistors  21  are patterned to be connected to the anodes  13 . 
     After formation of the anodes  13  and transistors  21 , a film formation step such as PVD or CVD, a mask step such as photolithography, and a thin film shape process step such as etching are executed to form the mesh-shaped protective insulating film  18  made of silicon nitride or silicon oxide so as to surround each anode  13 . A photosensitive resin film made of a photosensitive resin such as polyimide is formed on one surface of the transparent substrate  12 . The photosensitive resin film is partially exposed. Then, a removing liquid is applied to the photosensitive resin film to process the shape of the photosensitive resin film into a mesh pattern on the protective insulating film  18 . Accordingly, the mesh-shaped partition  20  made of the photosensitive resin is formed. The surrounded regions  19  surrounded by the protective insulating film  18  and partition  20  are formed. In each surrounded region  19 , the anode  13  is exposed ( FIG. 3D ). In exposing a negative photo-sensitive resin film, a portion that overlaps the protective insulating film  18  is irradiated with light. Conversely, in exposing a positive photosensitive resin film, a region surrounded by the protective insulating film  18  is irradiated with light. 
     Next, the side of the surface  12   a  of the transparent substrate  12 , i.e., the surfaces of the anodes  13 , protective insulating film  18 , and partition  20  are cleaned. The cleaning may be done by oxygen plasma cleaning under a pressure lower than the atmospheric pressure or by UV/ozone cleaning. A lyophilic process is executed for the surface of the anode  13  in each surrounded region  19 , and a liquid repellent process is executed for the surface of the partition  20 , as needed. This will be described in detail in the section “Lyophilic Process and Liquid Repellent Process”. The structure having the anodes  13 , transistors  21 , protective insulating film  18 , and partition  20  formed on the surface  12   a  of the transparent substrate  12  will be referred to as a driving substrate. 
     “(ii) Print Step” 
     As shown in  FIG. 5A , a red organic compound containing liquid  60   r  is applied on the wettability changeable layer  202  of the red plate  200 R. Examples of the applying method are dip coating, die coating, roll coating, and spin coating. In the wettability changeable layer  202 , the lyophilic region  202   a  irradiated with the active rays hν has a lyophilic effect. The liquid repellent region  202   b  that is not irradiated with the active rays hν has liquid repellency. Hence, a droplet of the organic compound containing liquid  60   r  sticks to only the lyophilic region  202   a  irradiated with the active rays hν. At this time, the red plate  200 R may be oscillated. Even if a small amount of the organic compound containing liquid  60   r  remains in the liquid repellent region  202   b , the remaining organic compound containing liquid  60   r  can be removed from the red plate  200 R by the surface tension of the organic compound containing liquid  60   r . The red plate  200 R may be tilted. In this case, the organic compound containing liquid  60   r  on the liquid repellent region  202   b  flows down due to its weight while the organic compound containing liquid  60   r  in the lyophilic region  202   a  remains. Alternatively, the red plate  200 R may be oscillated while being tilted. In this case, the unnecessary organic compound containing liquid  60   r  on the liquid repellent region  202   b  can be removed to the outside. 
     As shown in  FIG. 5B , a plate  200  is made to oppose the surface  12   a  of the transparent substrate  12  on which the transistors  21 , anodes  13 , and partition  20  are formed. The transparent substrate  12  and red plate  200 R are aligned such that the red anodes  13 (R) oppose the lyophilic regions  202   a  with the organic compound containing liquid. When at least one of an arm (not shown) which holds the red plate  200 R and a stage (not shown) on which the transparent substrate  12  is placed is appropriately moved, the organic compound containing liquids  60   r  that are projecting from the surface of the red plate  200 R respectively come into contact with the anodes  13 (R). The organic compound containing liquid  60   r  sticking to each lyophilic region  202   a  is transferred to a corresponding one of red anodes  13 (R). If the anode  13  is made of ITO, the metal oxide has a rough surface and wets well with the organic compound containing liquid  60   r . With this process, the EL layer  15 (R) that emits red light is formed on the anode  13 (R) corresponding to a pixel that emits red light in each surrounded region  19 (R) ( FIG. 5C ). Even when a small misalignment occurs, and the organic compound containing liquid  60   r  comes into contact with the side wall of the partition  20 , the organic compound containing liquid flows from the side wall of the partition  20  onto the red anode  13 (R). Hence, the variation in thickness of the formed red EL layer  15 (R) is not so large as to affect display. Since the surrounded regions  19 (R) are separated by the partition  20 , the organic compound containing liquid  60   r  transferred to the surrounded region  19 (R) does not leak to the adjacent surrounded region  19  in which an organic compound containing liquid of a different color should be transferred. 
     As in the red plate, droplets  60   g  of an organic compound containing liquid containing an organic compound that emits green light are respectively brought into contact with the anodes  13 (G) by using the green plate  200 G, thereby transferring the organic compound containing liquid to the anodes  13 (G). In this way, the green EL layer  15 (G) is formed on the anode  13 (G) in each surrounded region  19 (G) ( FIG. 6A ). Next, as in the red plate, droplets  60   b  of an organic compound containing liquid containing an organic compound that emits blue light are correspondingly brought into contact with the anodes  13 (G) by using the blue plate  200 B, thereby transferring the organic compound containing liquid to the anode  13 (B). In this way, the blue EL layer  15 (B) is formed on the anode  13 (B) in each surrounded region  19 (B) ( FIG. 6B ). The red EL layer  15 (R), green EL layer  15 (G), and blue EL layer  15 (B) need not always be formed in this order. In addition, the red EL layer  15 (R), green EL layer  15 (G), and blue EL layer  15 (B) need not always be arrayed in this order from the left side. 
     “(iii) Electrode Formation Step” 
     By a film formation method such as PVD or CVD using deposition or sputtering, the cathode  16  is formed on the entire surface to cover the EL layers  15  ( FIG. 6C ). After formation of the cathode  16 , the organic EL elements  11  are sealed by a sealing medium. 
     In the organic EL display panel  10  manufactured in the above way, a pixel circuit supplies a current to the organic EL element  11  in accordance with a signal input through the signal line  51  and scanning line  52 . In the organic EL element  11 , holes are injected from the anode  13  to the EL layer  15  while electrons are injected from the cathode  16  to the EL layer  15  so that a current flows. When the holes and electrons are transported and recombined in the EL layer  15 , the EL layer  15  emits light. Since the anode  13  and substrate  12  are transparent, the light emitted by the EL layer  15  exits from a lower surface  12   b  of the transparent substrate  12 . The lower surface  12   b  serves as a display surface. 
     As described above, in this embodiment, the plates  200 R,  200 G, and  200 B are made for the respective colors. The EL layers  15  are formed for each color by using a corresponding plate. Hence, the red EL layers  15 (R), green EL layers  15 (G), or blue EL layers  15 (B) can be formed simultaneously. That is, when transfer is executed only three times in (ii) print step, all the EL layers  15  on the transparent substrate  12  can be formed. For this reason, the organic EL display panel  10  can be manufactured in a short time. 
     Instead of forming the EL layers by using nozzles as in the inkjet method, the EL layers  15  are patterned by transfer using the plates  200 R,  200 G, and  200 B. The larger number of pixels on which EL layers should be formed becomes, the higher the film forming efficiency becomes. In addition, no clogging occurs, unlike the inkjet method. Hence, the EL layers  15  are prevented from having nonuniform thicknesses. Furthermore, the EL layers  15  can be precisely arrayed and formed, as compared to the inkjet method. 
     “Lyophilic Process and Liquid Repellent Process” 
     Before (ii) print step, as shown in  FIG. 7A , after the side of the surface  12   a  of the transparent substrate  12  is cleaned by pure water and dried, a second wettability changeable layer  14  that covers the anodes  13  and the entire partition  20  may be formed on a side of the surface  12   a  of the transparent substrate  12 . 
     The second wettability changeable layer  14  is the same as the wettability changeable layer  202  of the master member as the base of the plate  200  but need not always contain any photocatalyst. When the second wettability changeable layer  14  contains no photocatalyst, corrosion of the anode  13  can be suppressed. In addition, any decrease in hole injection effect from the anode  13  to the EL layer  15  can be suppressed. The second wettability changeable layer  14  can be formed in accordance with the same procedures as those for the wettability changeable layer  202 . If no photocatalyst is dispersed in the coating liquid to be changed to the second wettability changeable layer  14 , the resultant second wettability changeable layer  14  contains no photocatalyst. 
     Before (ii) print step, the entire second wettability changeable layer  14  has liquid repellency. The second wettability changeable layer  14  is a liquid repellent layer that repels the organic compound containing liquid. In (ii) print step, before the EL layers  15 (R),  15 (G), and  15 (B) of the respective colors are formed by using the plates, the second wettability changeable layer  14  is irradiated with the active rays hν in regions that overlap the anodes  13 (R),  13 (G), and  13 (B) of the respective colors. 
     More specifically, as shown in  FIG. 7A , before the EL layers  15 (R) are formed by using the red plate  200 R, only regions that overlap the surrounded regions  19 (R) corresponding to pixels that emit red light are irradiated with the active rays hν by using, e.g., the photomask substrate  203 α or photomask substrate  203 β (in  FIG. 7A , the photomask substrate  203 β prepared by forming the photocatalytic film  206  on the lower surface of the transparent substrate  204 ) used in making the red plate  200 R. With this process, the second wettability changeable layer  14  changes to the lyophilic layers  14 (R) having a lyophilic effect in the regions that overlap the red anodes  13 (R). 
     Next, as described above in (ii) print step, by using the red plate  200 R, a solution containing an EL material that emits red light is transferred and applied onto the lyophilic layers  14 (R) formed on the surfaces of the red anodes  13 (R). Before the organic compound containing liquid is transferred to the surrounded regions  19 (R), the second wettability changeable layer  14  is changed to the lyophilic layers  14 (R) having a lyophilic effect only in the surrounded regions  19 (R). Hence, the lyophilic layer wets well with the solution containing the EL material that emits red light. The second wettability changeable layer  14  having liquid repellency is formed on the surfaces of the partition  20  and the surrounded regions  19 (G) and  19 (B) of the remaining colors. The second wettability changeable layer  14  repels the solution containing the EL material that emits red light. For this reason, the solution containing the EL material that emits red light collects only in the red surrounded regions  19 (R). When the solvent in the solution dries, the EL layers  15 (R) are formed. The EL material that emits red light may be a polymer in the solution. Alternatively, a monomer or oligomer that causes polymerization after the solution may be used. 
     Next, only the green surrounded regions  19 (G) of the second wettability changeable layer  14  are irradiated with the active rays hν by using the photomask substrate  203 α or photomask substrate  203 β used in making the green plate. With this process, the second wettability changeable layer  14  changes to the lyophilic layers  14 (G) in the surrounded regions  19 (G) ( FIG. 7B ). After that, as described above in (ii) print step, by using the green plate  200 G, a solution containing an EL material that emits green light is transferred and applied onto the lyophilic layers  14 (G) formed on the surfaces of the green anodes  13 (G). The surfaces of the surrounded regions  19 (G) have the lyophilic layers  14 (G) and therefore wets well with the solution. However, the second wettability changeable layer  14  remains liquid repellent on the surfaces of the partition  20  and the surrounded regions  19 (B) of the remaining color. The second wettability changeable layer  14  repels the solution containing the EL material that emits green light. For this reason, the solution containing the EL material that emits green light collects only in the green surrounded regions  19 (G). When the solvent in the solution dries, the EL layers  15 (G) are formed. The EL material that emits green light may be a polymer in the solution. Alternatively, a monomer or oligomer that causes polymerization after the solution may be used. 
     Next, only the blue surrounded regions  19 (B) of the second wettability changeable layer  14  are irradiated with the active rays hν by using the photomask substrate  203 α or photomask substrate  203 β used in making the blue plate. With this process, the second wettability changeable layer  14  changes to the lyophilic layers  14 (B) in the surrounded regions  19 (B) ( FIG. 7C ). After that, as described above in (ii) print step, by using the blue plate, a solution containing an EL material that emits blue light is transferred and applied onto the lyophilic layers  14 (B) formed on the surfaces of the blue anodes  13 (B) corresponding to the EL layers  15 (B). The surfaces of the surrounded regions  19 (B) have the lyophilic layers  14 (B) and therefore wets well with the solution. However, the second wettability changeable layer  14  remains liquid repellent on the surface of the partition  20 . The second wettability changeable layer  14  repels the solution containing the EL material that emits blue light. For this reason, the solution containing the EL material that emits blue light collects only in the blue surrounded regions  19 (B). When the solvent in the solution dries, the EL layers  15 (B) are formed. The EL material that emits blue light may be a polymer in the solution. Alternatively, a monomer or oligomer that causes polymerization after the solution may be used. 
       FIGS. 7A to 7C  show the photomask substrate  203 β on which the photocatalytic film  206  is formed. When the second wettability changeable layer  14  contains a photocatalyst, the photomask substrate  203 α may be used. 
     For example, when the second wettability changeable layer  14  is formed by hydrolyzing and condensing a silazane compound having a fluoroalkyl group represented by general formula (5), the main chain of silicon and oxygen is formed along the surfaces of the anodes  13 , protective insulating film  18 , and partition  20 . The second wettability changeable layer  14  is very thin. Additionally, in the lyophilic layers  14 (R),  14 (G), and  14 (B), the fluoroalkyl group arranged in the direction of thickness of the second wettability changeable layer  14  is substituted with a hydroxyl group. For this reason, the lyophilic layers  14 (R),  14 (G), and  14 (B) in the surrounded regions  19  become thinner, i.e., the thickness falls between 0.0 nm (exclusive) and 1.0 nm (inclusive). That is, the lyophilic layers  14 (R),  14 (G), and  14 (B) are thinner than a portion (liquid repellent portion) that is not irradiated with light. Hence, even when any one of the lyophilic layers  14 (R),  14 (G), and  14 (B) is inserted between the anode  13  and the EL layer  15 , the insulating properties of the lyophilic layers  14 (R),  14 (G), and  14 (B) can be neglected. For this reason, hole injection from the anode  13  to the EL layer  15  is not impeded. 
     Instead of forming the second wettability changeable layer  14 , the surfaces of the anodes  13  may be imparted with a lyophilic effect, and the surface of the partition  20  may be imparted with liquid repellency by the following method. Before (ii) print step, the partition  20  is irradiated with a fluoride plasma such as CF 4  plasma. At this time, a radical species of fluorine reacts in the surface layer of the partition  20  and forms a fluoride (mainly a compound of fluorine and carbon) in the surface layer of the partition  20 . Accordingly, the surface of the partition  20  obtains liquid repellency. Next, the anodes  13  are irradiated with an oxygen plasma. The surface layers of the anodes  13  are ashed so that the fluoride layers in the surface layers of the anodes  13  are removed. Accordingly, the anodes  13  obtain a lyophilic effect. After that, the above-described (ii) print step is executed. 
     Second Embodiment 
     In this embodiment, an EL display panel  105  having EL layers  15  each constructed by a plurality of charge transport layers, as shown in the sectional view of  FIG. 8 , will be described. In the organic EL display panel  105 , each EL layer  15  has a multilayered structure in which a hole transport layer  151  and a light-emitting layer  152  of narrow sense are stacked in this order sequentially from an anode  13 . The remaining constituent elements of the organic EL display panel  105  are the same as those of the organic EL display panel  10  of the first embodiment. The same reference numerals as in the organic EL display panel  10  denote the same constituent elements in the organic EL display panel  105 , and a detailed description thereof will be omitted. Throughout the drawing, (R) is added to the light-emitting layer  152  of narrow sense, which emits red light. (G) is added to the light-emitting layer  152  of narrow sense, which emits green light. (B) is added to the light-emitting layer  152  of narrow sense, which emits blue light. (R), (G), or (B) is also added to the hole transport layer  151  corresponding to each color. 
     A method of manufacturing the EL display panel  105  will be described next with reference to  FIGS. 9A to 11C .  FIGS. 9A to 11C  are sectional views showing the method of manufacturing the EL display panel  105  according to the second embodiment. 
     First, as in the first embodiment, (i) driving substrate manufacturing step is executed to manufacture a driving substrate. The surface side of the driving substrate is cleaned by pure water. Then, a second wettability changeable layer  14  that covers the anodes  13  and an entire partition  20  is formed on an entire surface  12   a  of a transparent substrate  12 . 
     The second wettability changeable layer  14  is the same as a wettability changeable layer  202  but need not always contain any photocatalyst. When the second wettability changeable layer  14  contains no photocatalyst, corrosion of the anode  13  can be suppressed. In addition, any decrease in hole injection effect from the anode  13  to the EL layer  15  can be suppressed. The second wettability changeable layer  14  can be formed in accordance with the same procedures as those for the wettability changeable layer  202 . If no photocatalyst is dispersed in the coating liquid, the resultant second wettability changeable layer  14  contains no photocatalyst. 
     Next, as shown in  FIG. 9A , portions of the second wettability changeable layer  14  where a red hole transport layer  151 (R), green hole transport layer  151 (G), and blue hole transport layer  151 (B) (to be described later) should be formed are exposed by using a photomask substrate  203 γ. The photomask substrate  203 γ has a flat transparent substrate  204  that passes active rays hν. A mask  205  that does not pass the active rays hν and has a mesh pattern, like the partition  20 , is formed on a surface  204   a  of the transparent substrate  204 . Since the mask  205  has a mesh pattern, opening portions  205   a  arrayed in a matrix are formed in the mask  205 . That is, the array pattern of the opening portions  205   a  when viewed from the upper side corresponds to the array pattern of surrounded regions  19  corresponding to all pixels, i.e., R, G, and B pixels. A photocatalytic film  206  is formed on the lower surface of the transparent substrate  204  to cover the mask  205 . 
     When the photomask substrate  203 γ is used, the transparent substrate  204  is placed on the transparent substrate  12  such that the opening portions  205   a  oppose the surrounded regions  19 (R),  19 (G), and  19 (B). The transparent substrate  204  is irradiated with the active rays hν from the upper side. By the photocatalytic function of the photocatalytic film  206 , a functional group having liquid repellency in the second wettability changeable layer  14  is desorbed and substituted with a functional group having a lyophilic effect only on the anodes  13 (R),  13 (G), and  13 (B) (i.e., only on the portions irradiated with the light) so that lyophilic layers  14 X are formed. At this time, the second wettability changeable layer  14  that covers the surface of the partition  20  is shielded from the active rays hν by the mask  205 . Hence, the second wettability changeable layer  14  does not change to the lyophilic layer  14 X. 
     As shown in  FIG. 9B , the wettability changeable layer  202  of a plate  208 , which has a pattern with lyophilic regions  202   a  and liquid repellent region  202   b , is made to oppose the transparent substrate  12 . The lyophilic regions  202   a  of the plate  208  are arrayed in a matrix. The liquid repellent region  202   b  has a mesh pattern. That is, the array pattern of the lyophilic regions  202   a  when viewed from the upper side corresponds to that of the surrounded regions  19  corresponding to the pixels of all colors. The array pattern is almost the same as that of the lyophilic layers  14 X. Droplets  61  of a solution containing at least a hole transport material stick to the surfaces of the respective lyophilic regions  202   a  in equal amounts. The droplet  61  may be a solution containing an organic material such as a mixture of poly-(3, 4) ethylene dioxythiophene and polystyrene sulfonate. A solution in which a hole transport inorganic material is dispersed may be used. Alternatively, a mixture of the above solutions may be used. When a solution containing a hole transport material is applied on the entire surface of the plate  208 , the droplets  61  can have a predetermined pattern due to the lyophilic and liquid repellent effects of the lyophilic regions  202   a  and liquid repellent region  202   b  which are formed on the surface. 
     The above-described plate  208  is placed closer to the transparent substrate  12 . As shown in  FIG. 9C , the droplets  61  come into contact with the lyophilic layers  14 X of the transparent substrate  12  and are thus transferred onto the lyophilic layers  14 X. When the droplets dry, the hole transport layers  151 (R),  151 (G), and  151 (B) are formed. At this time, even when the droplet  61  comes into contact with the second wettability changeable layer  14  that covers the side wall surface of the partition  20 , the droplet  61  is repelled and inevitably flows onto the lyophilic layer  14 X. Since the droplet  61  spreads on the lyophilic layer  14 X in a uniform thickness, a hole transport layer  151  having a uniform thickness can be formed. At this time, all the hole transport layers  151 (R),  151 (G), and  151 (B) are made of the same material. 
     As shown in  FIG. 10A , light-emitting layers  152 (R) of narrow sense are formed by using a red plate  200 R. More specifically, a predetermined amount of a red organic compound containing liquid  152   r  is applied on each lyophilic region  202   a  of the red plate  200 R as a droplet. The red plate  200 R is aligned by moving at least one of the red plate  200 R and the transparent substrate  12  such that the red organic compound containing liquid  152   r  opposes the hole transport layer  151 (R) on each anode  13 (R) of the transparent substrate  12 . The organic compound containing liquid  152   r  is a liquid containing an organic compound that forms the light-emitting layer  152 (R) of narrow sense, or its precursor. The liquid may be a solution prepared by dissolving, as a solute, an organic compound that forms the light-emitting layer  152 (R) of narrow sense, or its precursor in a solvent. Alternatively, the liquid may be a dispersion prepared by dispersing an organic compound that forms the light-emitting layer  152 (R) of narrow sense, or its precursor in a liquid. 
     At least one of the red plate  200 R and transparent substrate  12  is moved to bring the red organic compound containing liquid  152   r  on the red plate  200 R into contact with the hole transport layer  151 (R) on each anode  13 (R) of the transparent substrate  12 . The red organic compound containing liquid  152   r  on the red plate  200 R is transferred onto the hole transport layer  151 (R) on each anode  13 (R). After drying, light-emitting layers  152 (R) of narrow sense are formed, as shown in  FIG. 10B . 
     As shown in  FIG. 11A , light-emitting layers  152 (G) of narrow sense are formed by using a green plate  200 G. More specifically, a predetermined amount of a green organic compound containing liquid  152   g  is applied on each lyophilic region  202   a  of the green plate  200 G as a droplet. The green plate  200 G is aligned by moving at least one of the green plate  200 G and the transparent substrate  12  such that the green organic compound containing liquid  152   g  opposes the hole transport layer  151 (G) on each anode  13 (G) of the transparent substrate  12 . The organic compound containing liquid  152   g  is a liquid containing an organic compound that forms the light-emitting layer  152 (G) of narrow sense, or its precursor. The liquid may be a solution prepared by dissolving, as a solute, an organic compound that forms the light-emitting layer  152 (G) of narrow sense, or its precursor in a solvent. Alternatively, the liquid may be a dispersion prepared by dispersing an organic compound that forms the light-emitting layer  152 (G) of narrow sense, or its precursor in a liquid. 
     At least one of the green plate  200 G and transparent substrate  12  is moved to bring the green organic compound containing liquid  152   g  on the green plate  200 G into contact with the hole transport layer  151 (G) on each anode  13 (G) of the transparent substrate  12 . The green organic compound containing liquid  152   g  on the green plate  200 G is transferred onto the hole transport layer  151 (G) on each anode  13 (G). After drying, light-emitting layers  152 (G) of narrow sense are formed. From the viewpoint of yield, the green organic compound containing liquid  152   g  is preferably transferred after the red organic compound containing liquid  152   r  transferred onto the anodes  13 (G) dries and changes to the light-emitting layers  152 (R) of narrow sense. If priority is placed on mass production, transfer may be executed before drying is ended. 
     As shown in  FIG. 11B , light-emitting layers  152 (B) of narrow sense are formed by using a blue plate  200 B. More specifically, a predetermined amount of a blue organic compound containing liquid  152   b  is applied on each lyophilic region  202   a  of the blue plate  200 B as a droplet. The blue plate  200 B is aligned by moving at least one of the blue plate  200 B and the transparent substrate  12  such that the blue organic compound containing liquid  152   b  opposes the hole transport layer  151 (B) on each anode  13 (B) of the transparent substrate  12 . The organic compound containing liquid  152   b  is a liquid containing an organic compound that forms the light-emitting layer  152 (B) of narrow sense, or its precursor. The liquid may be a solution prepared by dissolving, as a solute, an organic compound that forms the light-emitting layer  152 (B) of narrow sense, or its precursor in a solvent. Alternatively, the liquid may be a dispersion prepared by dispersing an organic compound that forms the light-emitting layer  152 (B) of narrow sense, or its precursor in a liquid. 
     At least one of the blue plate  200 B and transparent substrate  12  is moved to bring the blue organic compound containing liquid  152   b  on the blue plate  200 B into contact with the hole transport layer  151 (B) on each anode  13 (B) of the transparent substrate  12 . The blue organic compound containing liquid  152   b  on the blue plate  200 B is transferred onto the hole transport layer  151 (B) on each anode  13 (B). After drying, light-emitting layers  152 (B) of narrow sense are formed. From the viewpoint of yield, the blue organic compound containing liquid  152   b  is preferably transferred after the green organic compound containing liquid  152   g  transferred onto the anodes  13 (G) dries and changes to the light-emitting layers  152 (G) of narrow sense. If priority is placed on mass production, transfer may be executed before drying is ended. The red light-emitting layer  152 (R), green light-emitting layer  152 (G), and blue light-emitting layer  152 (B) need not always be formed in this order. In addition, the red light-emitting layer  152 (R), green light-emitting layer  152 (G), and blue light-emitting layer  152 (B) need not always be arrayed in this order. 
     As shown in  FIG. 11C , by a film formation method such as PVD or CVD using deposition or sputtering, a cathode  16  is formed on the entire surface to cover the light-emitting layers  152  of narrow sense. After formation of the cathode  16 , the organic EL elements  11  are sealed by a sealing medium (not shown). 
     In patterning the lyophilic regions  202   a  on the red plate  200 R, green plate  200 G, or blue plate  200 B, when the wettability changeable layer  202  contains a photocatalyst, the lyophilic regions  202   a  may be patterned by using a photomask substrate  203 α . When the wettability changeable layer  202  contains no photocatalyst, patterning may be executed by using the photomask substrate  203 α. In patterning the lyophilic regions  202   a  on the plate  208 , when the wettability changeable layer  202  contains a photocatalyst, the lyophilic regions  202   a  on the plate  208  may be patterned by using a photomask substrate obtained by removing the photocatalytic film  206  from the photomask substrate  203 γ. When the wettability changeable layer  202  contains no photocatalyst, patterning is executed by using the photomask substrate  203 γ. 
     If the application pattern accuracy of the droplets  61  and its transfer pattern accuracy to the transparent substrate  12  by the plate  208  are high, the second wettability changeable layer  14  and lyophilic layers  14 X need not always be formed on the transparent substrate  12 . 
     Third Embodiment 
     In this embodiment, an EL display panel  110  having no partition, as shown in the sectional view of  FIG. 12 , will be described. The remaining constituent elements of the organic EL display panel  110  are the same as those of the organic EL display panel  105  of the second embodiment. The same reference numerals as in the organic EL display panel  105  denote the same constituent elements in the organic EL display panel  110 , and a detailed description thereof will be omitted. 
     A method of manufacturing the organic display panel  110  will be described next with reference to  FIGS. 13A to 15C .  FIGS. 13A to 15C  are sectional views showing the method of manufacturing the EL display panel  110  according to the third embodiment. 
     As shown in  FIG. 3C , as in the first embodiment, signal lines  51  and scanning lines  52  are patterned on a transparent substrate  12 . An anode  13  and transistors  21  are patterned for each pixel on a surface  12   a  of the transparent substrate  12 . After that, a protective insulating film  18  is formed to cover the transistors  21  and interconnections such as the signal lines  51 . In the first embodiment, the partition  20  is patterned. In the third embodiment, no partition is formed. Next, as in the first embodiment, a second wettability changeable layer  14  having liquid repellency is formed on the entire surface on the side of the surface  12   a  of the transparent substrate  12  to cover the anodes  13  and protective insulating film  18 . The second wettability changeable layer  14  preferably contains no photocatalyst. 
     Next, as shown in  FIG. 13A , the second wettability changeable layer  14  is partially exposed by the photocatalyst by using a photomask substrate  203 γ, as in the second embodiment. More specifically, a transparent substrate  204  is placed on the transparent substrate  12  such that the array pattern of opening portions  205   a  opposes that of surrounded regions  19 . The transparent substrate  204  is irradiated with active rays hν from the upper side. By the photocatalytic function of the photocatalytic film  206 , a functional group having liquid repellency in the second wettability changeable layer  14  is desorbed and substituted with a functional group having a lyophilic effect only on the anodes  13 (R),  13 (G), and  13 (B) (i.e., only on the portions irradiated with the light) so that lyophilic layers  14 X are formed. At this time, the second wettability changeable layer  14  that covers the surface of the protective insulating film  18  which protects the transistors  21  is shielded from the active rays hν by a mask  205 . Hence, the second wettability changeable layer  14  does not change to the lyophilic layer  14 X. 
     As shown in  FIG. 13B , as in the second embodiment, a droplet  61  is applied on each lyophilic region  202   a  of a plate  208 . The plate  208  is placed closer to the transparent substrate  12 . The droplet  61  is a solution containing at least a hole transport material. The droplet  61  may be absolution containing an organic material such as a mixture of poly-(3, 4) ethylene dioxythiophene and polystyrene sulfonate. A solution in which a hole transport inorganic material is dispersed may be used. Alternatively, a mixture of the above solutions may be used. 
     Then, as shown in  FIG. 13C , the droplet  61  comes into contact with each lyophilic layer  14 X on the transparent substrate  12  and is selectively transferred onto the lyophilic layer  14 X. After drying, hole transport layers  151  are formed. At this time, even when the droplet  61  comes into contact with the second wettability changeable layer  14  that covers the side wall surface of the partition  20 , the droplet  61  is repelled and inevitably flows onto the lyophilic layer  14 X. Since the droplet  61  spreads on the lyophilic layer  14 X in a uniform thickness, a hole transport layer  151  having a uniform thickness can be formed. 
     As shown in  FIG. 14A , light-emitting layers  152 (R) of narrow sense are formed by using a red plate  200 R. More specifically, a predetermined amount of a red organic compound containing liquid  152   r  is applied on each lyophilic region  202   a  of the red plate  200 R. The red plate  200 R is aligned by moving at least one of the red plate  200 R and the transparent substrate  12  such that the red organic compound containing liquid  152   r  opposes the hole transport layer  151 (R) on each anode  13 (R) of the transparent substrate  12 . 
     At least one of the red plate  200 R and transparent substrate  12  is moved to bring the red organic compound containing liquid  152   r  on the red plate  200 R into contact with the hole transport layer  151 (R) on each anode  13 (R) of the transparent substrate  12 . The red organic compound containing liquid  152   r  on the red plate  200 R is transferred onto the hole transport layer  151 (R) on each anode  13 (R). After drying, light-emitting layers  152 (R) of narrow sense are formed, as shown in  FIG. 14B . 
     As shown in  FIG. 15A , light-emitting layers  152 (G) of narrow sense are formed by using a green plate  200 G. More specifically, a predetermined amount of a green organic compound containing liquid  152   g  is applied on each lyophilic region  202   a  of the green plate  200 G. The green plate  200 G is aligned by moving at least one of the green plate  200 G and the transparent substrate  12  such that the green organic compound containing liquid  152   g  opposes the hole transport layer  151 (G) on each anode  13 (G) of the transparent substrate  12 . 
     At least one of the green plate  200 G and transparent substrate  12  is moved to bring the green organic compound containing liquid  152   g  on the green plate  200 G into contact with the hole transport layer  151 (G) on each anode  13 (G) of the transparent substrate  12 . The green organic compound containing liquid  152   g  on the green plate  200 G is transferred onto the hole transport layer  151 (G) on each anode  13 (G). After drying, light-emitting layers  152 (G) of narrow sense are formed. From the viewpoint of yield, the green organic compound containing liquid  152   g  is preferably transferred after the red organic compound containing liquid  152   r  transferred onto the anodes  13 (G) dries and changes to the light-emitting layers  152 (R) of narrow sense. If priority is placed on mass production, transfer may be executed before drying is ended. 
     As shown in  FIG. 15B , light-emitting layers  152 (B) of narrow sense are formed by using a blue plate  200 B. More specifically, a predetermined amount of a blue organic compound containing liquid  152   b  is applied on each lyophilic region  202   a  of the blue plate  200 B. The blue plate  200 B is aligned by moving at least one of the blue plate  200 B and the transparent substrate  12  such that the blue organic compound containing liquid  152   b  opposes the hole transport layer  151 (B) on each anode  13 (B) of the transparent substrate  12 . 
     At least one of the blue plate  200 B and transparent substrate  12  is moved to bring the blue organic compound containing liquid  152   b  on the blue plate  200 B into contact with the hole transport layer  151 (B) on each anode  13 (B) of the transparent substrate  12 . The blue organic compound containing liquid  152   b  on the blue plate  200 B is transferred onto the hole transport layer  151 (B) on each anode  13 (B). After drying, light-emitting layers  152 (B) of narrow sense are formed. From the viewpoint of yield, the blue organic compound containing liquid  152   b  is preferably transferred after the green organic compound containing liquid  152   g  transferred onto the anodes  13 (G) dries and changes to the light-emitting layers  152 (G) of narrow sense. If priority is placed on mass production, transfer may be executed before drying is ended. The red light-emitting layer  152 (R), green light-emitting layer  152 (G), and blue light-emitting layer  152 (B) need not always be formed in this order. In addition, the red light-emitting layer  152 (R), green light-emitting layer  152 (G), and blue light-emitting layer  152 (B) need not always be arrayed in this order. 
     As shown in  FIG. 15C , by a film formation method such as PVD or CVD using deposition or sputtering, a cathode  16  is formed on the entire surface to cover the light-emitting layers  152  of narrow sense. After formation of the cathode  16 , the organic EL elements  11  are sealed by a sealing medium (not shown). 
     If the application pattern accuracy of the droplets  61  and its transfer pattern accuracy to the transparent substrate  12  by the plate  208  are high, the second wettability changeable layer  14  and lyophilic layers  14 X need not always be formed on the transparent substrate  12 . 
     In patterning the lyophilic regions  202   a  on the red plate  200 R, green plate  200 G, or blue plate  200 B, when the wettability changeable layer  202  contains a photocatalyst, a photomask substrate  203 α may be used in place of the photomask substrate  203 β. Alternatively, both the plate and photomask substrate may contain a photocatalyst. 
     Even in this embodiment, the red hole transport layers  151 (R), green hole transport layers  151 (G), or blue hole transport layers  151 (B) can be simultaneously formed, as in the second embodiment. In addition, the red light-emitting layers  152 (R), green light-emitting layers  152 (G), or blue light-emitting layers  152 (B) can be simultaneously formed for each color. Hence, the Organic EL display panel  110  can be manufactured in a short time. Furthermore, the EL layers  15  are patterned by transfer using the plates  200 R,  200 G, and  200 B. Hence, the EL layers  15  are prevented from having nonuniform thicknesses. Also, the EL layers  15  can be precisely arrayed and formed, as compared to the inkjet method. 
     In addition, a pattern having lyophilic regions and a liquid repellent region is formed on the second wettability changeable layer  14 . For this reason, the EL layer  15  for each sub pixel can be patterned without forming the partition  20 , unlike the first embodiment. 
     The present invention is not limited to the above embodiments, and various changes and modifications can be made within the spirit and scope of the invention. In the above embodiments, the cathode  16  is common to all the organic EL elements  11 . However, a cathode common to the organic EL elements  11  of the same color may be formed. That is, a red cathode common to red pixels, a green cathode common to green pixels, and a blue cathode common to blue pixels may be electrically insulated from each other. A cathode may be formed for each organic EL element  11 . When a cathode is formed for each organic EL element  11 , an anode common to all the organic EL elements  11  may be formed. In this case, the pixel circuit for each sub pixel is connected to the cathode. The organic EL element  11  may have a cathode, EL layer, and anode sequentially from the transparent substrate  12 . In the above embodiments, the present invention is applied to an active matrix organic EL display panel having the transistors  21 . The present invention can also be applied to a simple matrix driving display panel. 
     According to the present invention, optical material layers corresponding to a plurality of pixels can be simultaneously formed. Hence, the productivity can be increased as compared to the inkjet method which applies an optical material for each pixel. The liquid repellent portion of the wettability changeable layer of the pattern repels the optical material containing liquid. Most of the optical material containing liquid collects at a desired pattern portion. Since the amount of the optical material containing liquid can be a minimum necessary amount, the cost can be reduced. 
     Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.