JP3867698B2 - Electro-optical device, manufacturing method thereof, and electronic apparatus - Google Patents

Description

  The present invention relates to a technique for displaying an image using an electro-optic element that converts an electrical action such as supply of current or application of voltage into an optical action such as change in luminance (gradation) or transmittance.

  An apparatus that displays an image using an electro-optical element such as an organic light emitting diode (hereinafter referred to as “OLED (Organic Light Emitting Diode)”) element is a dot matrix that displays various images by a plurality of pixels arranged in a matrix. It is roughly divided into a type and a segment type that displays a specific image in a fixed manner. Among these, in the segment type electro-optical device, as shown in Patent Document 1, for example, the electro-optical element is driven by an electrode patterned so as to have a shape of an image to be displayed.

JP2001-244081 (paragraph 0027 and FIG. 1)

  However, in this segment type electro-optical device, it is necessary to create a photomask for patterning the electrodes for each image to be displayed. Therefore, it is very difficult to newly manufacture an electro-optical device having different images. There is a problem of cost. The present invention has been made in view of such circumstances, and an object thereof is to reduce the cost required for changing the displayed image.

  In order to achieve this object, the first feature of the electro-optical device according to the present invention is that a plurality of pixel electrodes arranged in a planar shape and a plurality of electric electrodes each provided on the surface of each pixel electrode are provided. An optical element; a counter electrode facing the plurality of pixel electrodes with the electro-optical elements interposed therebetween; and one or more pixel electrodes selected according to a predetermined image from the plurality of pixel electrodes and a power supply circuit And a conductive portion that is selectively provided between the power supply circuit and the one or more pixel electrodes. According to this configuration, since the conductive portion that electrically connects the pixel electrode selected according to the desired image and the power supply circuit is selectively provided, even when an electro-optical device that displays different images is manufactured. It is not necessary to prepare a photomask for patterning each electrode into a shape corresponding to the image. Therefore, according to the present invention, it is possible to reduce the cost of manufacturing electro-optical devices that display different images. The electro-optical element in the present invention is an element for converting an electrical action such as supply of current or application of voltage into a change in optical characteristics such as change in luminance (light emission amount) or transmittance. Typical examples of electro-optic elements are organic light emitting diode (OLED) elements such as organic electroluminescent elements and light emitting polymers.

  In another aspect of the present invention, a wiring connected to the power supply circuit is provided, and a conduction portion is provided between the one or more pixel electrodes and the wiring. According to this aspect, since it is possible to select whether each of the plurality of pixel electrodes is electrically connected to the power supply circuit, it is possible to display more various images. A specific form of this aspect will be described later in detail as the first embodiment. On the other hand, in another aspect of the present invention, a plurality of wirings each having one or a plurality of pixel electrodes connected thereto are provided, while the conduction portion is selected according to a predetermined image among the plurality of wirings. It is provided between each wiring connected to the pixel electrode and the power supply circuit. According to this aspect, since the presence or absence of electrical connection to the power supply circuit is selected for each of one or a plurality of pixel electrodes commonly connected to each wiring, the configuration can be simplified. A specific form of this aspect will be described later in detail as a second embodiment.

  In addition, a second feature of the electro-optical device according to the invention includes a plurality of pixel electrodes arranged in a planar shape, a plurality of electro-optical elements each provided on a surface of each pixel electrode, A counter electrode facing the plurality of pixel electrodes with an electro-optic element interposed therebetween, and a plurality of conductive portions, each provided between the pixel electrode and the power supply circuit, for conducting the pixel electrode and the power supply circuit. In other words, each of the resistance values includes a plurality of conductive portions selected according to a predetermined image. According to this configuration, a desired image (particularly a multi-gradation image) is displayed by appropriately selecting the resistance value of the conductive portion interposed between each pixel electrode and the power supply circuit. Accordingly, even in the case of manufacturing an electro-optical device that displays different images, it is not necessary to prepare a photomask for patterning each electrode into a shape corresponding to the image. The manufacturing cost can be reduced.

  In another aspect of the electro-optical device according to the second feature, a wiring connected to the power supply circuit is provided, and each of the plurality of conductive portions is provided between each pixel electrode and the wiring. According to this aspect, since the resistance value of the path from the pixel electrode to the power supply circuit can be selected for each of the plurality of pixel electrodes, more various images can be displayed. In addition, the specific form of this aspect is explained in full detail later as 3rd Embodiment. Further, in this aspect, the resistance value of each conducting portion is determined by various factors such as the number of conducting portions connecting each pixel electrode and the wiring and the kind of conductive material forming the conducting portion. On the other hand, in another aspect of the present invention, a plurality of wirings each having one or a plurality of pixel electrodes connected thereto are provided, and each of the plurality of conductive portions is provided between each wiring and the power supply circuit. According to this aspect, since the resistance value of the path leading to the power supply circuit is selected for each of one or a plurality of pixel electrodes commonly connected to each wiring, the configuration can be simplified.

  In a desirable aspect of the electro-optical device having the first and second features, a resistance layer formed of a conductive material having a predetermined resistivity and interposed between the pixel electrode and the counter electrode is provided. Provided. According to this aspect, even if any one of the pixel electrode and the counter electrode is short-circuited for some reason, it is possible to suppress the influence of the short-circuit from affecting another pixel electrode that is electrically connected to the pixel electrode. In this aspect, it is desirable that the resistance layer is provided on the side opposite to the observation side (that is, the side on which the observer who views the displayed image is located) as viewed from the electro-optic element. In this way, the light emitted from the electro-optic element (or the light transmitted through the electro-optic element) can be emitted to the observation side without passing through the resistance layer. The quality can be maintained.

  In the electro-optical device according to the present invention, a configuration in which a film body having an opening is provided on the surface of the base material and the conduction portion is provided in a region surrounded by the inner periphery of the opening is also employed. obtain. According to this configuration, it is possible to use a relatively inexpensive method (droplet discharge method) in which a conductive portion is formed by landing a droplet containing a conductive material in a region surrounded by the opening. However, the conducting portion can be formed by other methods.

  In order to achieve the above object, the first feature of the manufacturing method according to the present invention is that a plurality of pixel electrodes are arranged in a plane, and an electro-optic element is formed in the plane of each pixel electrode. A step of forming counter electrodes opposed to the plurality of pixel electrodes across the electro-optic elements, and one or more pixel electrodes selected according to a predetermined image among the plurality of pixel electrodes; And a step of selectively forming a conduction portion for conducting the power supply circuit. According to this method, an electro-optical device that displays a predetermined image can be obtained by selectively forming a conducting portion that conducts the pixel electrode and the power supply circuit. Therefore, a different photomask is prepared for each image to be displayed. do not have to. Therefore, according to the present invention, it is possible to reduce the cost of manufacturing electro-optical devices that display different images.

  Furthermore, the second feature of the manufacturing method according to the present invention is that a plurality of pixel electrodes are arranged in a plane, a step of forming an electro-optic element in the plane of each pixel electrode, Forming a counter electrode opposed to the plurality of pixel electrodes with an electro-optic element interposed therebetween, and a plurality of electrical connections between the pixel electrodes and the power supply circuit, each having a resistance value selected according to a predetermined image Forming a conductive portion. According to this method, since an electro-optical device that displays a predetermined image can be obtained by appropriately selecting the resistance value of each conductive portion interposed between the pixel electrode and the power supply circuit, for each image to be displayed There is no need to prepare a different photomask. Therefore, according to the present invention, it is possible to reduce the cost of manufacturing electro-optical devices that display different images.

  In the step of forming the conducting portion in the manufacturing method having the first and second features, the conducting portion is formed by ejecting a droplet containing a conductive material from an ejection port and landing the droplet. It is desirable to do. According to this method, the manufacturing cost can be reduced as compared with the case where the conductive portion is formed using a photolithography technique or the like.

  In addition, the order in which each process is implemented in the manufacturing method which concerns on the said 1st and 2nd characteristic is arbitrary. For example, in the manufacturing method according to the first feature, the step of forming the plurality of pixel electrodes, the step of forming the electro-optic element, the step of forming the counter electrode, and the step of forming the conductive portion are performed in any order. Also good.

  Specific embodiments for carrying out the present invention will be described with reference to the drawings. In the following, a mode in which the present invention is applied to an electro-optical device using an organic electroluminescence element as an example of an OLED element as an electro-optical element will be exemplified, but the scope to which the present invention can be applied is limited to this device. is not. Further, in the respective drawings shown below, the dimensions and ratios of the respective constituent elements are appropriately changed from the actual ones in order to make the respective constituent elements large enough to be recognized on the drawings.

<A: First Embodiment>
<A-1: Configuration of electro-optical device>
FIG. 1 is a block diagram illustrating a configuration of the electro-optical device according to the present embodiment. As shown in the figure, the electro-optical device 100 includes a display panel 1 and a power supply circuit 8. As shown in FIG. 1 and FIG. 2, which is a cross-sectional view of the display panel 1, the display panel 1 has a flat substrate 10 made of glass or plastic. The display panel 1 according to the present embodiment is a bottom emission type panel in which light emitted from an OLED element 21 described later is transmitted through the substrate 10 and emitted to the observation side (lower side in FIG. 2).

  On the plate surface of the substrate 10, a plurality of pixel electrodes 11 are arranged in a matrix form in the X direction and the Y direction. Each pixel electrode 11 is a substantially rectangular electrode functioning as an anode of the OLED element 21 and is formed of a light-transmitting conductive material such as indium tin oxide (ITO). Furthermore, a wiring 12 extending in the Y direction and having one end connected to the power supply circuit 8 is provided in a region corresponding to the gap between the pixel electrodes 11 adjacent in the X direction when viewed from the direction perpendicular to the base material 10. ing.

  As shown in FIG. 2, a partition wall 14 is provided on the plate surface of the substrate 10. The partition walls 14 are provided in a lattice shape so as to overlap with the gaps between the pixel electrodes 11 adjacent to each other in the X direction or the Y direction, and the plate surface of the base material 10 (more specifically, a second insulating layer 32 described later). Protruding from the surface of As shown in FIG. 2, the wiring 12 described above overlaps a portion extending in the Y direction in the lattice-shaped partition wall 14. The OLED element 21 as an electro-optical element is provided on the surface of the pixel electrode 11 so as to enter a space (depression) surrounded on all sides by the partition wall 14. Each OLED element 21 has a structure in which a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer are stacked in this order when viewed from the pixel electrode 11 side, and any of red, green, and blue Emits light of a wavelength corresponding to that color. Each OLED element 21 is laminated with a resistance layer 23 made of a conductive material having a predetermined resistivity.

  The plate surface of the base material 10 on which the partition wall 14 and the OLED element 21 are provided is covered with a counter electrode 15 connected to the power supply circuit 8. The counter electrode 15 is a single electrode provided to face the plurality of pixel electrodes 11 with each OLED element 21 interposed therebetween, and functions as a cathode of the OLED element 21. The counter electrode 15 in the present embodiment is formed of a light-reflective conductive material such as a single metal such as aluminum or silver or an alloy containing these metals as a main component. According to this configuration, light emitted from the OLED element 21 to the side opposite to the observation side (upper side in FIG. 2) can be reflected to the observation side by the counter electrode 15. The plate surface of the substrate 10 on which the counter electrode 15 is formed is covered with a sealing layer 17 over the entire area. The sealing layer 17 is a layer for protecting each element such as the counter electrode 15 formed on the substrate 10.

  On the other hand, the power supply circuit 8 is a circuit for supplying power to each wiring 12 and the counter electrode 15. More specifically, the power supply circuit 8 applies a higher power supply voltage side to the wiring 12, while applying a lower power supply voltage side (ground potential) to the counter electrode 15. As described above, when a voltage is applied between each pixel electrode 11 and the counter electrode 15, a current flows through the OLED element 21 and the OLED element 21 emits light. That is, a pixel is constituted by the pixel electrode 11 and the counter electrode 15 and the OLED element 21 sandwiched between both electrodes. Here, in the configuration in which the resistance layer 23 is not provided between each pixel electrode 11 and the counter electrode 15, when a certain pixel electrode 11 and the counter electrode 15 are short-circuited for some reason (for example, a defect of the OLED element 21). The potential of the wiring 12 is lowered to the potential of the counter electrode 15, and this influence also reaches other pixel electrodes 11 connected to the pixel electrode 11 through the wiring 12. On the other hand, under the configuration in which the resistance layer 23 is provided as in the present embodiment, even if one pixel electrode 11 and the counter electrode 15 are short-circuited, the pixel electrode 11 is connected to the pixel electrode 11 via the wiring 12. The influence exerted by the short circuit on the pixels of the other connected pixel electrodes 11 (pixel electrodes 11 arranged in the Y direction) can be suppressed. As shown in FIG. 2, in the present embodiment, a configuration in which the resistance layer 23 is interposed between the OLED element 21 and the counter electrode 15 is illustrated, but the resistance layer 23 is connected to the pixel electrode 11. A configuration interposed between the OLED element 21 and the OLED element 21 can also be adopted. However, in the bottom emission type display panel 1, since the light emitted from the OLED element 21 is emitted from the pixel electrode 11 to the observation side through the base material 10, from the viewpoint of ensuring luminance by suppressing light loss. Then, as shown in FIG. 2, the resistance layer 23 is provided on the side opposite to the observation side when viewed from the OLED element 21 (that is, the light emitted from the OLED element 21 does not pass through the resistance layer 23 and the substrate 10 It can be said that the configuration of emitting light to the side is desirable.

  The electro-optical device 100 according to the present embodiment is a device that fixedly displays a specific image (hereinafter referred to as “target image”). In order to realize this display, power is supplied from the power supply circuit 8 only to a plurality of pixels (hereinafter sometimes referred to as “display pixels”) selected from among a large number of pixels as constituting the target image. It has become so. In the present embodiment, as shown in FIG. 1, among the plurality of pixel electrodes 11, the pixel electrode 11 of the display pixel is electrically connected to the wiring 12, while other pixels (hereinafter referred to as “non-display pixels”). In some cases, the pixel electrode 11 is insulated from the wiring 12. When a voltage is applied from the power supply circuit 8 to the wiring 12 under this configuration, the wiring 12 is connected only to the pixel electrode 11 of the display pixel among the plurality of pixel electrodes 11 forming a column along the wiring 12. A voltage is selectively applied through the vias. As a result, only the OLED element 21 of the display pixel emits light and the target image is displayed.

  Here, FIG. 3 is an enlarged plan view showing elements related to each pixel. Of the two pixel electrodes 11 shown enlarged in FIG. 3, the upper pixel electrode 11 is a pixel electrode 11 constituting a display pixel, and the lower pixel electrode 11 is a pixel electrode 11 constituting a non-display pixel. . 4 is a cross-sectional view taken along line IV-IV in FIG. 3, and FIG. 5 is a cross-sectional view taken along line V-V in FIG. As shown in FIG. 3, each wiring 12 extending in the Y direction has a protruding portion 121 that protrudes toward the pixel electrode 11 (X direction). Further, as shown in FIGS. 4 and 5, the plate surface of the base material 10 on which the wiring 12 is formed is covered with the first insulating layer 31 over the entire area. The first insulating layer 31 is a film body formed of an insulating material such as a resin material, and a portion opened so as to penetrate the first insulating layer 31 in the thickness direction (hereinafter referred to as a “conductive opening”). ) 311 is provided for each pixel. When viewed from the direction perpendicular to the plate surface of the base material 10, as shown in FIG. 3, the conduction opening 311 partially overlaps the protrusion 121 of the wiring 12 and extends in the X direction. It has become. As shown in FIGS. 3 and 4, the pixel electrode 11 and the wiring 12 (and thus the power supply circuit 8) are conducted in the conduction opening 311 corresponding to the display pixel among the plurality of pixels. A conducting portion 34 (a hatched portion in FIG. 3) is provided. More specifically, the conductive portion 34 is formed so as to enter a space (depression) surrounded by the inner peripheral edge of the conductive opening 311 with the base material 10 as a bottom surface (that is, to fill the conductive opening 311). The The conductive portion 34 is formed of various conductive materials such as gold and copper. As described above, the protruding portion 121 of the wiring 12 is provided so as to protrude inward from the inner peripheral edge of the conductive opening 311, and therefore, the protruding portion 121 and the conductive portion 34 provided in the conductive opening 311, Touch. On the other hand, as shown in FIGS. 3 and 5, the conduction portion 34 is not provided in the conduction opening 311 corresponding to the non-display pixel among the plurality of pixels.

  The surface of the first insulating layer 31 is covered with the second insulating layer 32. The second insulating layer 32 is a film body made of an insulating material such as a resin material, like the first insulating layer 31. As shown in FIG. 4, a portion corresponding to the display pixel in the second insulating layer 32 is provided so as to cover the conductive portion 34. On the other hand, as shown in FIG. 5, the portion corresponding to the non-display pixel in the second insulating layer 32 enters the space surrounded by the inner peripheral edge of the opening 311 for conduction with the base material 10 as the bottom surface ( That is, it is provided so as to fill the opening 311 for conduction). As shown in FIG. 3, the second insulating layer 32 has the second insulating layer 32 at a position in the region of the opening 311 for conduction as viewed from the direction perpendicular to the base material 10 and does not overlap the protruding portion 121 of the wiring 12. An opening 321 penetrating the insulating layer 32 in the thickness direction is provided.

  On the other hand, the pixel electrode 11 has an extending portion 111 that extends so as to overlap the opening 321 of the second insulating layer 32. As shown in FIG. 4, the extension portion 111 of the pixel electrode 11 constituting the display pixel enters the opening 321 and reaches the conduction portion 34 which is the bottom surface. With this configuration, the pixel electrode 11 constituting the display pixel is electrically connected to the wiring 12 and the power supply circuit 8 via the conduction portion 34. On the other hand, as shown in FIG. 5, since the non-display pixel is not provided with the conductive portion 34, the extension portion 111 of the pixel electrode 11 constituting the non-display pixel enters the opening 321 and the base material 10. Reach the board surface. Accordingly, the pixel electrode 11 constituting the non-display pixel is electrically insulated from the wiring 12 by the second insulating layer 32. The structure above the pixel electrode 11 is as described with reference to FIG. In this way, the display pixel and the non-display pixel differ only in the presence or absence of the conduction portion 34.

<A-2: Manufacturing method of electro-optical device>
Next, a method for manufacturing the electro-optical device 100 described above will be described. In the following, the process from the formation of the wiring 12 to the formation of the pixel electrode 11 will be described with reference to FIG. 6 corresponding to the cross-sectional view of FIG. The process will be described with reference to FIG. 7 corresponding to the sectional view of FIG.

  First, as shown in FIG. 6A, the wiring 12 having the protrusion 121 is formed on the plate surface of the substrate 10. More specifically, after a conductive thin film made of aluminum, silver, copper, or the like is formed by a film forming technique such as sputtering, the wiring 12 is formed by performing a patterning process using a photolithography technique on the thin film. can get. Subsequently, as illustrated in FIG. 6B, the first insulating layer 31 having the conductive opening 311 is formed so as to cover the plate surface of the base material 10. Specifically, a photosensitive organic material such as polyimide, acrylic, or polyamide is applied on the substrate 10 and then cured by heating, and the thin film is exposed and developed using a predetermined photomask. A first insulating layer 31 is obtained.

  Next, as shown in FIG. 6C, the conductive portion 34 is selectively formed with respect to the one corresponding to the display pixel among the plurality of conductive openings 311 provided in the first insulating layer 31. . For this formation, a droplet discharge method (inkjet method) is used. That is, as shown in FIG. 6C, after the discharge port 71 is moved above the conductive opening 311 corresponding to the display pixel among the large number of conductive openings 311, A droplet containing a conductive material is discharged and landed in the opening 311 for conduction. By repeating this process for all the display pixels and then drying, the conductive portion 34 is selectively formed only in the display pixels. On the other hand, a droplet that becomes the conductive portion 34 is not discharged to the conductive opening 311 corresponding to the non-display pixel. The material of the droplets discharged from the discharge port 71 in this step is made of various conductive materials such as metal materials (for example, gold, silver, copper, palladium or nickel), conductive polymers or superconductive materials. Fine particles (hereinafter referred to as “conductive particles”) dispersed in a liquid such as water may be employed. In view of the discharge from the discharge port 71, the particle size of the conductive particles is preferably about 50 nm (nanometer) to about 0.1 μm (micrometer). Moreover, in order to disperse | distribute electroconductive particle in a liquid efficiently, you may coat the surface of each electroconductive particle with an organic material. For example, the conducting portion 34 is formed by adding xylene to toluene in which fine particles having a diameter of about 10 nm made of gold are dispersed and discharging a liquid having a viscosity of about 3 mPa · s (millipascal second) from the discharge port 71. Is done.

  Next, as shown in FIG. 6D, a second insulating layer 32 having an opening 321 is formed so as to cover the surface of the first insulating layer 31. The second insulating layer 32 is formed of a common material in the same process as the first insulating layer 31. Further, as shown in FIG. 6E, the pixel electrode 11 having the extending portion 111 is formed on the surface of the second insulating layer 32 so as to correspond to each of the display pixel and the non-display pixel. The pixel electrode 11 is formed by forming a conductive and light-transmitting thin film made of indium tin oxide, indium oxide, zinc oxide-based amorphous, or the like by a film forming technique such as sputtering, and then applying a photolithography technique to the thin film. It is obtained by performing a patterning process using The extension 111 of the pixel electrode 11 obtained in this way enters the opening 321 of the second insulating layer 32 and contacts the conductive portion 34 in the display pixel, while the conductive portion of the first insulating layer 31 in the non-display pixel. It reaches the surface of the substrate 10 through the common opening 311. Note that when the display panel 1 is a top emission type, the pixel electrode 11 is not required to be light transmissive. Therefore, a conductive material having light reflectivity such as a single metal such as aluminum or silver or an alloy containing these as a main component. The pixel electrode 11 is formed of a material (or a conductive material that does not have optical transparency).

Subsequently, as shown in FIG. 7A, the partition wall 14 is formed on the surface of the second insulating layer 32. Specifically, a photosensitive organic material such as polyimide, acrylic or polyamide is applied on the second insulating layer 32 and then cured by heating, and this thin film is exposed and developed using a predetermined photomask. Thus, a lattice-like partition wall 14 is obtained. Further, the partition wall 14 is subjected to plasma treatment using a gas such as CF ₄ , SiF ₄ or BF ₃ as a reaction gas, and the surface thereof is modified so as to exhibit liquid repellency (water repellency). Instead of modifying the surface of the partition wall 14, the partition wall 14 itself may have liquid repellency by adding a fluoride to the organic material to be the partition wall 14.

  Next, as shown in FIG. 7B, OLED elements 21 are formed in each of a large number of regions partitioned by the partition walls 14. For this formation, a droplet discharge method (inkjet method) is used. That is, as shown in FIG. 7B, after the discharge port 72 is moved above the region where the OLED element 21 is to be formed, a droplet containing an electro-optical material is discharged from the discharge port 72. To land on the surface of the pixel electrode 11. The OLED element 21 is obtained by repeating this for all pixels and then drying. The hole transport layer of the OLED element 21 is formed of, for example, a polythiophene derivative, a polypyrrole derivative, or a material obtained by doping them. More specifically, a dispersion obtained by dispersing 3,4-polyethylenedioxythiophene in polystyrene sulfonic acid as a solvent and adding water (PEDOT / PSS dispersion) is discharged from the discharge port 72 to be positive. A hole transport layer is formed. In addition, the light emitting layer of the OLED element 21 includes, for example, a polyfluorene derivative (PV), a polyparaphenylene vinylene derivative (PPV), a polyphenylene derivative (PP), a polyparaphenylene derivative (PPP), a polyvinyl carbazole (PVK), and a polythiophene derivative. , Polydialkylfluorene (PDAF), polyfluorenebenzothiadiazole (PFBT), polyalkylthiophene (PAT), or polymethylphenylsilane (PMPS). In addition to these polymer materials, polymer materials such as perylene dyes, coumarin dyes or rhodamine dyes, rubrene, perylene, 9,10-diphenylanthracene, tetraphenylbutadiene, Nile red, coumarin 6 or quinacridone. The light emitting layer can also be formed by a material doped with a low molecular material.

As described above, since the surface of the partition wall 14 exhibits liquid repellency, the droplet containing the electro-optic material efficiently stays in the space (depression) surrounded by the partition wall 14. In the step shown in FIG. 6E, if the pixel electrode 11 that is the landing point of the liquid droplet is formed of a material having a lyophilic surface, the liquid droplet discharged from the discharge port 72 is removed from the pixel electrode 11. Can be landed efficiently on the surface. Further, from the viewpoint of efficiently retaining droplets at the bottom of the space partitioned by the partition wall 14, the first layer exhibiting lyophilicity and the second layer exhibiting liquid repellency are viewed from the substrate 10 side. A method of forming the partition walls 14 by forming the thin films laminated in order is also suitable. Alternatively, the partition wall 14 is formed by molding a thin film in which a first layer made of an inorganic material such as SiO ₂ and a second layer made of an organic material such as acrylic or polyimide are viewed in this order and laminated in this order. A method of performing plasma treatment on the partition wall 14 can also be adopted. According to this method, since the degree of surface modification differs between the first layer and the second layer (the second layer exhibits higher liquid repellency than the first layer), the droplets are efficiently retained. be able to.

  Next, as illustrated in FIG. 7C, the resistance layer 23 is formed so as to overlap each OLED element 21. The resistance layer 23 is made of various conductive materials having a predetermined resistivity such as a semiconductor material such as polysilicon, or a dispersion of 3,4-polyethylenedioxythiophene / polystyrene sulfonic acid (PEDOT / PSS) or an organic silicon material. Formed by material. When the resistance layer 23 is formed of a semiconductor material, the resistance value can be arbitrarily controlled for each pixel by appropriately adjusting the thickness and the amount of impurities implanted. Similarly to the conductive portion 34, the resistance layer 23 is made of various metals such as gold, silver, copper, palladium, nickel, or a liquid material in which fine particles made of various conductive materials such as a conductive polymer and a superconductor are dispersed. May be formed. In this case, a droplet discharge method can be used for forming the resistance layer 23. That is, the resistance layer 23 is formed by discharging droplets in which conductive fine particles are dispersed from the discharge port (not shown) toward the substrate 10 and landing on the surface of the OLED element 21. In this method, the resistance value of the resistance layer 23 can be arbitrarily controlled by appropriately adjusting the dispersion amount (concentration) of the conductive particles in the solvent and the droplet amount.

Subsequently, as illustrated in FIG. 7D, the counter electrode 15 is formed so as to cover the entire surface of the base material 10 (that is, so as to cover the partition wall 14 and the OLED element 21). For this formation, various film forming techniques such as vacuum evaporation and sputtering are used. The counter electrode 15 is made of various conductive materials such as various simple materials such as aluminum, magnesium, lithium or calcium, and alloys containing these materials as main components. Note that the counter electrode 15 may be formed by stacking a plurality of layers each made of a different material. For example, the counter electrode 15 can be formed by stacking Li ₂ O and Al, stacking LiF and Al, or stacking MgF ₂ and Al. Further, in the case of the top emission type display panel 1, in order to suppress the loss of light from the OLED element 21 toward the observation side (the side opposite to the base material 10), a conductive material having light transmittance such as indium tin oxide. The counter electrode 15 is formed of a conductive material.

  Then, the sealing layer 17 is formed so that the whole surface of the base material 10 may be covered (refer FIG. 2). The sealing layer 17 is formed of various inorganic compounds, and is preferably formed of a silicon compound, that is, silicon nitride, silicon oxynitride, silicon oxide, or the like. However, the sealing layer 17 may be formed of other materials such as alumina, tantalum oxide, titanium oxide, and other ceramics. Thus, when the sealing layer 17 is formed of an inorganic compound, the adhesion between the sealing layer 17 and the cathode 15 is increased, particularly when the cathode 15 is formed of an inorganic compound. It becomes a dense layer with no oxygen and moisture barrier properties.

  Alternatively, the sealing layer 17 may be formed by laminating a plurality of layers made of different materials selected from the various silicon compounds described above. More specifically, a layer made of a silicon compound and a layer made of silicon oxynitride are stacked in this order as viewed from the cathode 15 side, or a layer made of silicon oxynitride and a layer made of silicon oxide are made into a cathode It is desirable to form the sealing layer 17 by laminating in this order as viewed from the 15 side. On the other hand, in the top emission type display panel 1, the sealing layer 17 needs to have light transmittance. For this reason, it is desirable that the light transmittance when the sealing layer 17 is irradiated with light belonging to the visible light region is 80% or more by appropriately adjusting the material and film thickness of the sealing layer 17. Moreover, it is good also as a structure by which the sealing member (not shown) was bonded together in the inert gas atmosphere so that the whole surface of the base material 10 might be covered. If the OLED element 21 is disposed in a sealed space surrounded by the sealing member and the base material 10 under this configuration, the OLED element 21 can be isolated from oxygen and moisture in the atmosphere.

  After the sealing layer 17 described above is formed, the power supply circuit 8 is mounted in the vicinity of the edge of the substrate 10 to obtain the electro-optical device 100. According to the electro-optical device 100 according to the present embodiment, the configuration is extremely simple as compared with a general electro-optical device of an active matrix driving system in which a switching element such as a thin film transistor is provided for each pixel (that is, High-definition and high-definition display can be realized regardless of the configuration provided with only the minimum necessary components for image display.

  As described above, according to the present embodiment, only the pixel electrode 11 corresponding to the pixel constituting the target image among the many pixel electrodes 11 is selectively connected to the power supply circuit 8 via the conduction unit 34. Therefore, the electro-optical device 100 that displays a desired target image is obtained by appropriately selecting whether or not the conductive portion 34 is formed according to the content of the target image, and the base material 10 such as the pixel electrode 11 or the OLED element 21. The process of forming the above elements is made common regardless of the contents of the target image. In particular, it is not necessary to change the photomask for forming the pixel electrode 11 according to the content of the target image. Therefore, according to the present embodiment, the cost for creating the display panel 1 for displaying different target images is remarkably reduced. In other words, it is possible to create the display panel 1 that can display various target images according to the user's request without increasing the manufacturing cost. In addition, in the present embodiment, there is an advantage that the conductive portion 34 is formed by a relatively inexpensive droplet discharge method.

<B: Second Embodiment>
Next, the configuration of the electro-optical device according to the second embodiment of the invention will be described. In the first embodiment, the configuration in which only the pixel electrode 11 constituting the display pixel among the pixel electrodes 11 is selectively connected to the wiring 12 is exemplified. On the other hand, in the electro-optical device 101 according to the present embodiment, as shown in FIG. 8, all the pixel electrodes 11 are connected to the wirings 12, and a display pixel is configured among these wirings 12. Only the wiring 12 connected to the pixel electrode 11 (hereinafter sometimes referred to as “display wiring”) is selectively connected to the power supply circuit 8 via the conducting portion 34. According to this configuration, the target image is displayed by the light emission of a plurality of pixels arranged in the Y direction.

  FIG. 9 is a cross-sectional view showing the relationship between the display wiring 12 and a wiring (hereinafter referred to as “power wiring”) 81 drawn from the power supply circuit 8, and FIG. 10 is a wiring other than the display wiring among the plurality of wirings 12. 12 (hereinafter, also referred to as “non-display wiring”) and a power supply wiring 81 are cross-sectional views. As shown in these drawings, in the vicinity of the region where the power supply circuit 8 is mounted in the base material 10, a power supply wiring 81 and a wiring 12 to which pixel electrodes 11 arranged in the Y direction are connected in common. Are spaced apart from each other with their ends facing each other.

  The surface of the substrate 10 on which the power supply wiring 81 and the wiring 12 are formed is covered with the first insulating layer 31. A conductive opening 311 that penetrates the first insulating layer 31 in the thickness direction is provided in a portion of the first insulating layer 31 where the end of the power supply wiring 81 and the end of the wiring 12 approach each other. . Here, FIG. 11 is an enlarged plan view showing a portion where the power supply wiring 81 and the wiring 12 are close to each other. As shown in the figure, when viewed from a direction perpendicular to the plate surface of the substrate 10, the end of the power supply wiring 81 and the end of the wiring 12 protrude from the inner peripheral edge of the opening 311 for conduction and The shape reaches the inside of the opening 311. As shown in FIG. 9, the conduction openings 34 made of various conductive materials are provided in the conduction openings 311 corresponding to the display wirings 12 among the plurality of wirings 12. More specifically, the conductive portion 34 is formed so as to enter the space (depression) surrounded by the conductive opening 311 with the base material 10 as the bottom surface (that is, fill the conductive opening 311). As described above, each end portion of the power supply wiring 81 and the wiring 12 is provided so as to protrude inward from the inner peripheral edge of the conduction opening 311, so that the display wiring 12 is connected to the power supply wiring 81 via the conduction portion 34. It will be conducted. On the other hand, as shown in FIG. 10, the conduction portion 34 is not provided in the conduction opening 311 corresponding to the non-display wiring 12. Therefore, the non-display wiring 12 is electrically insulated from the power supply circuit 8. The surface of the first insulating layer 31 is covered with the second insulating layer 32. When a voltage is applied from the power supply circuit 8 to the power supply wiring 81 under this configuration, the voltage is selectively applied only to the pixel electrodes 11 arranged along the display wiring 12 among the plurality of wirings 12. . As a result, only the OLED element 21 of the display pixel (that is, the pixel connected to the display wiring 12) emits light and the target image is displayed. The first insulating layer 31, the second insulating layer 32, and the conducting portion 34 in the present embodiment are made of the same material as the first insulating layer 31, the second insulating layer 32, and the conducting portion 34 in the first embodiment, respectively. It can be formed in the same process. For example, the conductive portion 34 is obtained by discharging a droplet containing a conductive material from the discharge port 71 and landing in the conductive opening 311.

  On the other hand, the relationship between each pixel and the wiring 12 is common regardless of whether it is a display pixel or a non-display pixel. That is, an opening is provided in the first insulating layer 31 and the second insulating layer 32 that cover the wiring 12 formed on the substrate 10, and the pixel electrode 11 provided on the surface of the second insulating layer 32 has this opening. Conductive with the wiring 12 through the portion. The configuration above the pixel electrode 11 is the same as that in the first embodiment.

  As described above, according to the present embodiment, the electro-optical device 101 that displays a desired target image can be obtained by appropriately selecting whether or not the conductive portion 34 is formed according to the content of the target image. As in the first embodiment, the cost for creating the display panel 1 for displaying different target images is remarkably reduced. In this embodiment, since the presence / absence of conduction between the wiring 12 and the power supply wiring 81 is selected, it is not possible to distinguish between conduction and non-conduction for each of a plurality of pixels connected to the common wiring 12. However, even in this configuration, high-definition display with multiple gradations is possible by making the resistance value of the resistance layer 23 different for each pixel. In the present embodiment, the configuration in which all of the plurality of pixel electrodes 11 arranged in the Y direction are connected to the wiring 12 is illustrated. However, as in the first embodiment, the conduction of each pixel electrode 11 to the display wiring 12 is performed. Further, non-conduction may be appropriately selected according to the target image.

<C: Third Embodiment>
Next, the configuration of the electro-optical device according to the third embodiment of the invention will be described. In the first embodiment and the second embodiment, the configuration in which the presence / absence of conduction between each pixel electrode 11 and the power supply circuit 8 is appropriately selected is illustrated. On the other hand, in the present embodiment, each of the plurality of pixel electrodes 11 is electrically connected to the power supply circuit 8, while the resistance value between each pixel electrode 11 and the power supply circuit 8 is the content of the target image. It is selected accordingly.

  FIG. 12 is a block diagram illustrating a configuration of the electro-optical device 102 according to the present embodiment. As shown in the figure, each of the plurality of pixel electrodes 11 arranged in a matrix on the substrate 10 has a resistor 35 connected to a wiring 12 extending in the Y direction and having one end connected to the power supply circuit 8. Connected through. The resistance value of each resistor 35 is appropriately selected according to the content of the target image. Specifically, the resistance value of the resistor 35 connected to the pixel electrode 11 of the pixel with high luminance in the target image is lower than the resistance value of the resistor 35 connected to the pixel electrode 11 of the pixel with low luminance. . According to this configuration, the voltage applied to the pixel electrode 11 connected to the resistor 35 having a low resistance value is higher than the voltage applied to the pixel electrode 11 connected to the resistor 35 having a high resistance value. Therefore, the luminance of the pixel constituted by the pixel electrode 11 according to the former is higher than the luminance of the pixel constituted by the pixel electrode 11 according to the latter, and as a result, the target image is displayed with multiple gradations. .

  Here, FIG. 13 is an enlarged plan view showing elements related to the pixels, and FIG. 14 is a cross-sectional view taken along line XIV-XIV in FIG. As shown in these drawings, in the configuration in the vicinity of the pixel electrode 11 in the present embodiment, the wiring 12 formed on the plate surface of the substrate 10 is covered with the first insulating layer 31 and the second insulating layer 32. 3 is common to the electro-optical device 100 shown in FIG. 3 in that the pixel electrode 11 is formed so that the extending portion 111 enters the opening 321 of the second insulating layer 32. On the other hand, the configuration of this embodiment is different from the electro-optical device 100 according to the first embodiment in that three conduction openings 311 are formed for one pixel. In the present embodiment, the conduction portion 34 (hatching in FIG. 13 is selectively performed with respect to one to three conduction openings 311 selected according to the luminance of the target image among these three conduction openings 311. A given part) is provided. The conducting portion 34 is for conducting the pixel electrode 11 and the wiring 12 (and thus the power supply circuit 8). FIG. 13 illustrates a configuration in which the conductive portion 34 is formed only in the two conductive openings 311 located in the upper part of the drawing. On the other hand, as shown in FIG. 14, the conduction portion 34 is not formed in one conduction opening 311 positioned below in the figure. In this configuration, the pixel electrode 11 and the wiring 12 (and thus the power supply circuit 8) are electrically connected through only two conductive portions 34. Thus, by selecting the number of conducting portions 34 for conducting the pixel electrode 11 and the wiring 12 for each pixel according to the content of the target image, the resistance value between the pixel electrode 11 and the wiring 12 can be reduced. It is adjusted. For example, the resistance value between the pixel electrode 11 in which all three conduction openings 311 are provided with conduction parts 34 and the wiring 12 is provided with the conduction part 34 only in one conduction opening 311. It becomes lower than the resistance value between the pixel electrode 11 and the wiring 12. That is, the resistor 35 shown in FIG. 12 corresponds to the conduction portion 34 whose number is appropriately selected according to the content of the target image. The manufacturing method of the electro-optical device 100 having this configuration is the same as the method described with reference to FIGS. However, in the process shown in FIG. 6B, three conductive openings 311 are formed for one pixel, while in the process shown in FIG. 6C, the number corresponding to the content of the target image is set. The conductive portion 34 is formed by discharging a droplet containing a conductive material from the discharge port 71 to the conductive opening 311.

  As described above, in the present embodiment, the contents of the target image (more specifically, the levels of the pixels constituting the target image) are interposed between each of the large number of pixel electrodes 11 and the power supply circuit 8. A resistor 35 having a resistance value selected according to the tone) is provided. Therefore, the process of forming various components such as the pixel electrode 11 is made common regardless of the content of the target image. Therefore, according to the present embodiment, as in the first and second embodiments, the cost for creating the display panel 1 for displaying different target images is significantly reduced.

<D: Modification>
The embodiment described above is merely an example. Various modifications can be made to this embodiment without departing from the spirit of the present invention. Specifically, the following modifications can be considered.

(1) The configurations shown in the first to third embodiments can be appropriately combined and employed. For example, in the third embodiment, as in the first embodiment, the non-display pixel that does not constitute the target image is not formed with the conductive portion 34 in any of the three conductive openings 311, and the non-display pixel The pixel electrode 11 and the power supply circuit 8 may be electrically insulated. Further, as shown in the second embodiment, the plurality of conduction openings 311 shown in the third embodiment are formed between the power supply wiring 81 and the wiring 12 of the power supply circuit 8, and some or all of them are formed. Alternatively, the conductive portion 34 may be selectively provided in the conductive opening 311 so that the resistance value between each wiring 12 and the power supply circuit 8 varies depending on the content of the target image.

(2) In the third embodiment, the configuration in which the three conductive openings 311 are formed is illustrated, but the number of the conductive openings 311 for each pixel is arbitrary. As the number of the conductive openings 311 increases, the applied voltages to the pixel electrodes 11 become more diversified, so that a multi-tone target image can be displayed. Further, in the third embodiment, the configuration in which the resistance value between the pixel electrode 11 and the power supply circuit 8 is adjusted according to the number of the conductive portions 34 is illustrated, but one conductive opening 311 and While providing the conduction | electrical_connection part 34, it is good also as a structure which changes suitably the resistance value itself of the conduction | electrical_connection part 34 according to the content of the object image. For example, the resistance value of the conductive portion 34 of each pixel may be made different by selecting one of a plurality of conductive materials having different low efficiencies to form the conductive portion 34. Further, when the conductive portion 34 is formed by the droplet discharge method, the resistance value of the conductive portion 34 of each pixel is made different by appropriately adjusting the concentration of the conductive material contained in the droplet and the volume of the droplet. You may make it let.

(3) The method of forming the conduction part 34 and the OLED element 21 is not limited to the droplet discharge method. For example, the OLED element 21 can also be formed by a method of transferring a material constituting the OLED element 21 onto the base material 10 with a laser. Further, the OLED element 21 may be formed over the entire display region by vapor deposition, spin coating, or the like. As described above, even when the OLED element 21 is formed over the entire surface of the substrate 10, various images can be displayed by selectively forming the conductive portion 34. That is, by selectively forming the conductive portion 34 for a specific pixel, it is possible to distinguish between a display pixel and a non-display pixel, and the amount of light emitted from the display pixel to the observation side (or other electro-optical material is transmitted). The amount of light emitted to the observation side) can be arbitrarily adjusted by appropriately varying the resistance value of the conductive portion 34 corresponding to the display pixel.

(4) In the above-described embodiment, the bottom emission type display panel 1 is exemplified, but the present invention is naturally applied to the top emission type display panel 1. Here, in the bottom emission type display panel 1, the configuration in which the resistance layer 23 is interposed between the OLED element 21 and the counter electrode 15 is illustrated from the viewpoint of suppressing the loss of the emitted light amount, but the top emission type display panel is illustrated. 1, a configuration in which a resistance layer 23 is interposed between the pixel electrode 11 and the OLED element 21 is desirable.

(5) The present invention can also be applied to an electro-optical device using an electro-optical element other than an OLED element. As an electro-optical device to which the present invention can be applied, a plasma display panel (PDP) using a high-pressure gas such as helium or neon as an electro-optical element, a field emission display (FED) using a phosphor as an electro-optical element, or the like Is mentioned.

<E: Electronic equipment>
Next, an electronic apparatus having the electro-optical device according to the invention will be described. FIG. 15 is a perspective view showing a configuration of a mobile phone having an electro-optical device to which the present invention is applied. As shown in this figure, the mobile phone 1200 includes a plurality of operation buttons 1202 operated by a user, a mouthpiece 1204 for outputting a sound received from another terminal device, and a sound transmitted to the other terminal device. In addition to the mouthpiece 1206 for inputting, the electro-optical device 100 (or the electro-optical device 101 or 102) for displaying various images is provided. The display area of the electro-optical device 100 is divided into a first area 1001 and a second area 1002. Among these, the first area 1001 is an area where various images are displayed while being appropriately changed by a dot matrix type display method. On the other hand, the second area 1002 is an area in which the target image is fixedly displayed by applying the present invention. That is, in the second region 1002, only the display pixels selected as constituting the target image among the plurality of pixels are electrically connected to the power supply circuit 8.

  In addition to the mobile phone shown in FIG. 15, electronic devices that can use the electro-optical device according to the present invention include a notebook computer, a liquid crystal television, a viewfinder type (or monitor direct view type) video recorder, Car navigation devices, pagers, electronic notebooks, calculators, word processors, workstations, videophones, POS terminals, devices equipped with touch panels, and the like.

1 is a block diagram illustrating a configuration of an electro-optical device according to a first embodiment of the invention. FIG. FIG. 3 is a cross-sectional view illustrating a configuration of a display panel in the electro-optical device. FIG. 3 is an enlarged plan view showing a configuration near a pixel electrode in the display panel. It is sectional drawing seen from the IV-IV line in FIG. 3, and is a figure which shows the structure in connection with a display pixel. FIG. 5 is a cross-sectional view taken along line VV in FIG. 3 and shows a configuration related to non-display pixels. FIG. 10 is a process drawing illustrating the manufacturing method of the same electro-optical device. FIG. 10 is a process drawing illustrating the manufacturing method of the same electro-optical device. FIG. 6 is a block diagram illustrating a configuration of an electro-optical device according to a second embodiment of the invention. FIG. 3 is a cross-sectional view of a display panel in the same electro-optical device, showing a configuration related to display wiring. It is sectional drawing of the same display panel, and is a figure which shows the structure in connection with non-display wiring. It is a top view which expands and shows a power supply wiring and wiring among the display panels. FIG. 10 is a block diagram illustrating a configuration of an electro-optical device according to a third embodiment of the invention. 3 is an enlarged plan view showing a configuration in the vicinity of a pixel electrode in a display panel of the electro-optical device. It is sectional drawing seen from the XIV-XIV line | wire in FIG. It is a perspective view which shows the structure of the mobile telephone which is an example of the electronic device which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100,101,102 ... Electro-optical device, 1 ... Display panel, 10 ... Base material, 11 ... Pixel electrode, 111 ... Extension part, 12 ... Wiring, 121 ... Projection part, 14 ... Partition wall 15 .. Counter electrode 17... Sealing layer 21... OLED element 23 .. Resistance layer 31... First insulating layer 311 .. Opening for conduction 32. 321 ... Opening part 34 ... Conducting part 35 ... Resistor 71, 72 ... Discharge port 8 ... Power supply circuit 81 ... Power supply wiring

Claims (16)

A plurality of pixel electrodes arranged in a plane;
A plurality of electro-optic elements each provided on the surface of each pixel electrode;
A counter electrode facing the plurality of pixel electrodes across the electro-optic elements;
A conductive portion that is selectively provided between one or more pixel electrodes selected according to a predetermined image among the plurality of pixel electrodes and a power supply circuit, and conducts the one or more pixel electrodes and the power supply circuit. And an electro-optical device. Comprising wiring connected to the power supply circuit;
The electro-optical device according to claim 1, wherein the conductive portion is provided between the one or more pixel electrodes and the wiring. A plurality of wirings each having the pixel electrode connected thereto;
The electricity according to claim 1, wherein the conduction portion is provided between each of the plurality of wirings connected to one or more pixel electrodes selected according to a predetermined image and the power supply circuit. Optical device. A plurality of pixel electrodes arranged in a plane;
A plurality of electro-optic elements each provided on the surface of each pixel electrode;
A counter electrode facing the plurality of pixel electrodes across the electro-optic elements;
A plurality of conduction portions, each provided between the pixel electrode and the power supply circuit, for conducting the pixel electrode and the power supply circuit, each of which has a resistance value selected according to a predetermined image. And an electro-optical device. Comprising wiring connected to the power supply circuit;
The electro-optical device according to claim 4, wherein each of the plurality of conductive portions is provided between each pixel electrode and the wiring. The electro-optical device according to claim 5, wherein the resistance value of each conduction portion is a value corresponding to the number of conduction portions connecting the pixel electrodes and the wiring. The electro-optical device according to claim 5, wherein the resistance value of each conductive portion is a value corresponding to a type of a conductive material forming the conductive portion. A plurality of wirings each having the pixel electrode connected thereto;
The electro-optical device according to claim 4, wherein each of the plurality of conductive portions is provided between each of the wirings and the power supply circuit. The electro-optical device according to claim 1, further comprising: a resistance layer formed of a conductive material having a predetermined resistivity and interposed between the pixel electrode and the counter electrode. The electro-optical device according to claim 9, wherein the resistance layer is provided on a side opposite to the observation side when viewed from the electro-optical element. A film body provided on the surface of the substrate and having an opening;
The electro-optical device according to claim 1, wherein the conductive portion is provided in a region surrounded by an inner peripheral edge of the opening of the film body. The electro-optical device according to claim 1, wherein the electro-optical element is an organic light-emitting diode element.   An electronic apparatus comprising the electro-optical device according to claim 1. Forming a plurality of pixel electrodes in a planar arrangement;
Forming an electro-optic element on the surface of each pixel electrode;
Forming a counter electrode facing the plurality of pixel electrodes across the electro-optic elements;
And a step of selectively forming a conducting portion for conducting one or more pixel electrodes selected according to a predetermined image among the plurality of pixel electrodes and a power supply circuit. Forming a plurality of pixel electrodes in a planar arrangement;
Forming an electro-optic element on the surface of each pixel electrode;
Forming a counter electrode facing the plurality of pixel electrodes across the electro-optic elements;
Forming a plurality of conducting portions each conducting the pixel electrode and the power supply circuit with a resistance value selected in accordance with a predetermined image. 16. The electro-optical device according to claim 14, wherein in the step of forming the conductive portion, the conductive portion is formed by discharging a droplet including a conductive material from a discharge port and landing the droplet. Production method.

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