JP2005266755A - Method for manufacturing electrooptical device, electrooptical device and electronic equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing an electrooptical device with which a panel is thinned without damaging terminals in the panel on which substrates for the electrooptical device are stuck to the opposite substrate, the electrooptical device manufactured by the method and electronic equipment using the same. <P>SOLUTION: In the case of manufacturing an organic EL display device or a liquid crystal display device on which the plurality of substrates 2 for the elecrooptic device are stuck to the large-sized substrate 3, the opposite (sealing) substrate 4 is stuck on the side where the terminals 20 of the substrates 2 for the electrooptical device are formed, the opposite (sealing) substrate 4 is ground and thinned at the state. In this case, the terminals 20 of the substrates 2 for the electrooptical device are covered with the opposite (sealing) substrate 4, after thinning, the sealing substrate 4 is cut off with a laser and the terminals 20 are exposed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing an electro-optical device, an electro-optical device, and an electronic apparatus using the same.

  Among various electro-optical devices, for example, in an organic EL display device, a substrate having a pixel switching element and an organic EL element in each of a large number of pixel regions arranged in a matrix is used. The organic EL element injects electrons and holes from the electron injection electrode and the hole injection electrode into the light emitting part, recombines the injected electrons and holes at the emission center to bring the organic molecules into an excited state, and the organic molecules Produces fluorescence when it returns from the excited state to the ground state. Here, if a fluorescent material that is a luminescent material is selected, the luminescent color can be changed, so that a color image can be displayed.

  Such an organic EL display device is required to have a size exceeding 30 inches as in the case of a liquid crystal device, but in that case, the substrate is also enlarged. For this reason, a line for manufacturing a TFT (Thin Film Transistor) as a pixel switching element is enlarged. In addition, increasing the size of the substrate itself decreases the yield in the cleaning process and the film forming process. Furthermore, if an attempt is made to construct a TFT with a low-temperature polysilicon TFT for the purpose of using an inexpensive glass substrate as the substrate, laser annealing for crystallizing amorphous silicon into polysilicon becomes unstable.

In view of this, it has been proposed that a large-sized organic EL display device is configured by planarly arranging a plurality of substrates having a size that can be manufactured with conventional techniques and facilities. Such an enlargement technique includes a method of arranging a plurality of electro-optical device substrates in a plane after forming all of the pixel switching elements and organic EL elements on the electro-optical device substrate, and an electro-optical device. And a method of forming a plurality of electro-optic device substrates in a planar manner after forming pixel switching elements on the substrate, and then forming an organic EL element on each electro-optic device substrate. However, in the latter case, there is an advantage that the joint between the substrates for the electro-optical device is not conspicuous (see, for example, Patent Documents 1 and 2).
JP 2001-102171 A JP 2002-297063 A

  However, as in the techniques described in Patent Documents 1 and 2, when a plurality of electro-optical device substrates are bonded to a large substrate, the electro-optical device is thicker and the weight cannot be reduced. There is a problem. In addition, there is a problem that a new type of electro-optical device having a curved substrate cannot be manufactured. However, when a thin substrate is used from the beginning, there is a problem in that the substrate is broken during the manufacturing process and the yield tends to decrease. Therefore, it is conceivable to reduce the thickness of the panel in a state where a large substrate or a sealing substrate (counter substrate) is bonded to the electro-optic device substrate to form a panel. There is a problem in that the terminals formed on the substrate for the electro-optical device are also etched and damaged. Such a problem also occurs in a liquid crystal device or the like.

  In view of the above problems, a method for manufacturing an electro-optical device capable of reducing the thickness of a panel obtained by bonding an electro-optical device substrate and a counter substrate without damaging terminals, and an electro-optical device manufactured by this method And providing an electronic device using the same.

  In order to solve the above-described problem, in the present invention, in a panel in which one side of a terminal for an electro-optical device substrate on which a terminal is formed is bonded to a counter substrate and the terminal is covered with the counter substrate, the panel is fixed to a surface plate. It has a fixing step for fixing with wax, a thinning step for polishing and thinning the panel, and a cutting step for cutting the counter substrate to expose the terminals.

  In the present invention, in order to reduce the thickness of the panel, since the thickness is reduced in the state of the panel in which the electro-optical device substrate and the counter substrate are bonded together, the counter substrate is thick until then. For this reason, even when a hard substrate such as a glass substrate is used as the counter substrate and the counter substrate is thinned to, for example, 100 μm or less, and further to 50 μm or less, the counter substrate does not break during the manufacturing process. Further, since the thinning in the state of the panel is performed not by chemical etching but by polishing, the terminals formed on the electro-optical device substrate are not etched. Furthermore, since the terminal is covered with the counter substrate during polishing, the terminal is not damaged. Furthermore, since the panel is fixed on the surface plate with wax during polishing, the panel can be removed from the surface plate simply by melting the wax after the polishing is completed. In addition, if the fixing is performed with wax, the fixing stress does not concentrate on a part of the panel, so that the panel is not cracked. In addition, since the wax melts at a temperature of about 80 ° C., the electro-optical material does not deteriorate even if the panel holds the electro-optical material such as liquid crystal or EL material.

  In the present invention, in the thinning step, the panel is polished and thinned while the panel is fixed on the surface plate with the wax, and the surface of the panel polished in the lapping step is thinned. It is preferable to continuously perform the polishing step for smooth polishing.

  In the present invention, in the fixing step, the wax is heated and melted in a recess formed on the upper surface of the surface plate, the panel is immersed in the melted wax, and a fluid pressure is applied to the panel. It is preferable that the panel is pressed against the surface plate, and then the wax is cooled and solidified to fix the panel on the surface plate with the wax. As a method of applying the fluid pressure, there is a method of jetting compressed air from the head toward the upper surface of the panel. Further, a diaphragm having elasticity may be put on the panel, and a fluid may be supplied into a space on the opposite side to the side where the panel is arranged, of the two spaces partitioned by the diaphragm. If comprised in this way, since a uniform force can be applied to the whole panel, a panel can be fixed on a surface plate with a suitable attitude | position, and it can grind | polish with high precision.

  In the present invention, in the cutting step, the counter substrate is preferably cut by a laser. If comprised in this way, a counter substrate can be efficiently cut | disconnected in the state of a panel.

  In the present invention, the panel is characterized in that one or a plurality of the electro-optical device substrates are bonded to the counter substrate. With this configuration, it is possible to efficiently thin a small to large panel in which one or a plurality of electro-optical device substrates are arranged in a plane. That is, in the case of a small panel, a plurality of panels can be simultaneously reduced, and in the case of a large panel in which a plurality of small substrates are bonded together, a large area can be thinned collectively.

  The present invention can be applied to the manufacture of an EL display device. In this case, the electro-optic device substrate holds an electroluminescence material as an electro-optic material on the one surface side.

  The present invention can also be applied to the manufacture of a liquid crystal device. In this case, the electro-optical device substrate holds a liquid crystal as an electro-optical material between the one surface side and the counter substrate. .

  A self-luminous electro-optical device to which the present invention is applied can be used for a portable electronic device such as a mobile phone or a mobile computer, and can also be used for an electronic device having a large screen exceeding 30 inches.

  Hereinafter, an electro-optical device, a manufacturing method thereof, and an electronic apparatus using the electro-optical device according to the invention will be described with reference to the drawings. In each drawing to be referred to, the scale may be different for each layer or each member in order to make the size recognizable on the drawing.

[Embodiment 1]
(Overall configuration of organic EL display device)
1A and 1B are a perspective view and a plan view of an active matrix organic EL display device according to Embodiment 1 of the present invention. FIG. 2 is an explanatory diagram showing an electrical configuration of the organic EL display device shown in FIG.

  In FIG. 1, an organic EL display device 1 according to this embodiment includes a large panel 1 ′ of 30 inches or more using so-called tiling technology, and a plurality of electro-optical device substrates 2 (TFT array substrates) ( In this embodiment, four sheets are bonded to the large substrate 3 in a state of being arranged in a plane. In the panel 1 ′, a gas barrier sealing substrate 4 (opposing substrate) is bonded to the electro-optical device substrate 2 on the surface opposite to the large substrate 3. The large substrate 3 is approximately the same size as a plurality of electro-optical device substrates 3. On the other hand, the sealing substrate 4 is smaller than a plurality of electro-optical device substrates 2, and a part of the one surface side 21 of the electro-optical device substrate 2 protrudes from the edge of the sealing substrate 4. ing. Therefore, the flexible wiring board 7 on which the IC 70 is COF mounted can be connected to each of the terminals 20 formed on the end portion on the one surface side 21 of the electro-optical device substrate 2.

  Here, in the medium / small panel, the electro-optical device substrate 2 shown in FIG. 1 is composed of two sheets or one sheet. In addition, any of the electro-optical device substrate 2, the large substrate 3, and the sealing substrate 4 is a glass substrate that has been thinned to, for example, 100 μm or less, and further 50 μm or less, by a thinning process described later.

  As shown in FIG. 2, the organic EL display device 1 of the present embodiment also has a plurality of scanning lines 131 and scanning lines on the electro-optical device substrate 2 in terms of an equivalent circuit in the same manner as a known organic EL display device. A plurality of signal lines 132 extending in a direction intersecting with 131 and a plurality of power supply lines 133 extending in parallel with the signal lines are wired. Further, the pixel region 100 is formed at each intersection of the scanning line 131 and the signal line 132. For example, the data line driving circuit 103 including a shift register, a level shifter, a video line, and an analog switch is connected to the signal line 132. Further, the scanning line drive circuit 104 including a shift register and a level shifter is connected to the scanning line 131.

(Pixel configuration)
FIG. 3 is an enlarged sectional view showing a pixel region in the organic EL display device shown in FIG.

  As shown in FIGS. 2 and 3, each pixel region 100 of the organic EL display device 1 of the present embodiment has a pixel switching TFT 123 in which a scanning signal is supplied to a gate electrode via a scanning line 131, and the TFT 123. A storage capacitor 135 for holding an image signal supplied from the signal line 132 via the pixel line, and a pixel switching (driving) TFT 124 for supplying the image signal held by the storage capacitor 135 to the gate electrode are formed. Yes. In order to form such TFTs 123 and 124, the substrate 2 for the electro-optical device is provided with a base protective film 2c made of a silicon oxide film on a base material made of a glass substrate, and on the base protective film 2c. An island-shaped semiconductor film 141 made of a low-temperature polysilicon film is formed. A source region 141a and a drain region 141b are formed in the semiconductor film 141 by high-concentration P ion implantation, and a portion where P is not introduced serves as a channel region 141c. A gate insulating film 142 is formed on the surface side of the base protective film 2c and the semiconductor film 141, and a gate electrode 143 (scanning line) made of Al, Mo, Ta, Ti, W, or the like is formed on the gate insulating film 142. ing. A transparent first interlayer insulating film 144a and a second interlayer insulating film 144b are formed on the surface side of the gate electrode 143 and the gate insulating film 142. The gate electrode 143 is provided at a position corresponding to the channel region 141c of the semiconductor film 141. In addition, contact holes 145 and 146 connected to the source and drain regions 141a and 141b of the semiconductor film 141 are formed in the interlayer insulating films 144a and 144b. A transparent pixel electrode 111 made of ITO or the like is formed in a predetermined shape on the second interlayer insulating film 144b. A TFT 124 is connected to the pixel electrode 111 through a contact hole 145.

  The pixel region 100 is further sandwiched between a pixel electrode (anode) 111 into which a drive current flows from the power supply line 133 when electrically connected to the power supply line 133 via the TFT 124, and the pixel electrode 111 and the cathode 12. An organic EL element 101 (self-emitting element) including the light emitting functional layer 110 (organic functional layer) is formed.

  The organic functional layer 110 includes, for example, a hole injection / transport layer 110a laminated on the pixel electrode 111 and a light emitting layer (organic EL layer) 110b formed on the hole injection / transport layer 110a. Yes. An electron injection / transport layer may be formed between the light emitting layer 110b and the cathode. The hole injection / transport layer 110a has a function of injecting holes into the light emitting layer 110b and a function of transporting holes inside the hole injection / transport layer 110a. In the light emitting layer 110b, the holes injected from the hole injection / transport layer 110a and the electrons injected from the cathode 12 side recombine to obtain light emission. Here, the large number of pixel regions 100 correspond to each color of red (R), green (G), and blue (B), and the correspondence of such colors corresponds to the type of material constituting the organic functional layer 110. It is prescribed by.

  The cathode 12 includes a calcium layer 12a and an aluminum layer 12b, and is formed on substantially the entire surface of the electro-optical device substrate 2 excluding the terminal formation region. The aluminum layer 12b reflects the light emitted from the light emitting layer 110b to the electro-optical device substrate 2 side. The aluminum layer 12b may be composed of an Ag film, a laminated film of Al and Ag, or the like in addition to the Al film.

In the organic EL display device 1 of this embodiment, in the pixel region 100, the partition 112 is formed as a bank so as to surround the peripheral portion of the pixel electrode 111. As will be described later, the partition 112 defines an application region of a liquid composition that is ejected and applied by an ink jet method (liquid ejection method) when the organic functional layer 110 is formed. The composition is formed with a uniform thickness. In this embodiment, the partition 112 includes, for example, an inorganic bank layer 112a located on the substrate side, and an organic bank layer 112b formed on the inorganic bank layer 112a. The inorganic bank layer 112a is made of, for example, an inorganic material such as SiO ₂ or TiO ₂ . The organic bank layer 112b is formed of a resist having heat resistance and solvent resistance such as acrylic resin and polyimide resin.

  The sealing substrate 4 prevents oxidation of the cathode 12 or the organic functional layer 110 by preventing intrusion of water and oxygen, and a flat surface such as an epoxy resin on the one surface side 21 of the electro-optical device substrate 2. It is bonded together via a sealing resin 40 having a function to make it. The large substrate 3 is bonded to the other surface side 22 of the electro-optical device substrate 2 via a transparent adhesive 30.

  In the organic EL display device 1 configured as described above, when the scanning line 131 is driven and the TFT 123 is turned on, the potential of the signal line 132 at that time is held in the holding capacitor 135, and according to the state of the holding capacitor 135. Thus, the conduction state of the driving TFT 124 is controlled. Further, when the driving TFT 124 is turned on, a current flows from the power supply line 133 to the pixel electrode 111 through the channel, and further, in the organic EL element, a current flows to the cathode 12 through the organic functional layer 110. The organic functional layer 110 emits light according to the amount of current at this time. The light emitted from the organic functional layer 110 to the large substrate 3 side is emitted to the observer side, while the light emitted from the organic functional layer 110 to the side opposite to the large substrate 3 is reflected by the cathode 12 to be large. It is emitted from the substrate 3 to the observer side.

(Production method)
4A and 4B are explanatory diagrams at a stage where TFTs, pixel electrodes, and terminals have been formed on the electro-optical device substrate in the method of manufacturing the organic EL display device shown in FIG. 5A to 5D are process cross-sectional views illustrating a process of thinning the completed electro-optical device substrate. 6A to 6E are process cross-sectional views illustrating a process of bonding a plurality of electro-optical device substrates whose thickness has been reduced in the previous process to a large substrate. 7A and 7B are explanatory diagrams of an organic functional layer forming step in the method for manufacturing the organic EL display device shown in FIG. 8A to 8E are process cross-sectional views illustrating a process of thinning the panel in the manufacturing process of the display device. FIGS. 9A to 9D are explanatory views showing a process of cutting a panel after thinning and connecting a flexible wiring board to a terminal in a manufacturing process of a display device.

  In manufacturing the organic EL display device 1, in this embodiment, as shown in FIGS. 4A and 4B, circuit elements such as TFTs 123 and 124, the pixel electrode 111 of the organic EL element 101, the terminals 20, and the partition walls 112 is formed on the electro-optical device substrate 2. Until this process is performed, the electro-optical device substrate 2 is a thick glass substrate 2 'before being thinned, and the thickness thereof is, for example, 0.5 mm.

  Next, as shown to FIG. 4 (A), (B) and FIG. 5 (A), the protective film 6 is stuck on the one surface side 21 of the board | substrate 2 for electro-optical apparatuses (protective film sticking process). The protective film 6 is a so-called UV film, and includes a UV release layer 62 between the film substrate 61 and the adhesive layer 63 as shown in FIG. The protective film 6 is affixed to the entire surface including the region where the terminals 20 are formed on the one surface side 21 of the electro-optical device substrate 2. The electro-optical device substrate 2 may be irradiated with laser light and cut together with the protective film 6 to adjust the outer shape of the electro-optical device substrate 2. Laser cutting of the electro-optical device substrate 2 is performed for other electro-optical devices in a state where at least one of the plurality of substrate sides of the electro-optical device substrate 2 is arranged as shown in FIGS. This is performed on the side adjacent to the substrate 2. In addition, alignment marks indicating laser irradiation positions are preferably formed at the four corners of the electro-optical device substrate 2. When such laser cutting is performed, the cut surface becomes a right angle, so that the electro-optical device substrates 2 can be bonded with high positional accuracy in a state where the organic EL display device 1 is assembled. Accordingly, when the light emitting functional layer 110 is formed by an inkjet method described later, the light emitting functional layer 110 can be formed with high accuracy at a predetermined position on the electro-optical device substrate 2. Further, it is possible to prevent generation of chips during polishing.

  Next, in the polishing apparatus 200 shown in FIG. 5B, the electro-optical device substrate 2 is thinned by polishing. Since the surfaces of the plurality of electro-optical device substrates 2 are aligned by such polishing, the plurality of electro-optical device substrates 2 and the large-sized substrate 3 can be easily placed on the surface plate 210, as will be described later. Can be bonded with high accuracy.

  In order to perform such polishing, first, a plurality of electro-optical device substrates 2 are arranged and fixed on the surface plate 210 of the polishing apparatus 200 (fixing step). The polishing apparatus 200 includes a ceramic surface plate 210 in which a concave portion 220 is formed in a portion where the electro-optical device substrate 2 is disposed, and the concave portion 220 is filled with wax 250. Accordingly, after the wax 250 is heated and melted to a temperature of about 80 ° C. indirectly or directly via the surface plate 210, the one surface side 21 is placed on the surface of the molten wax 250. A plurality of directed electro-optical device substrates 2 are arranged so as to be planarly arranged, and fluid pressure is applied to the electro-optical device substrate 2 to press the electro-optical device substrate 2 into the recess 220. For this purpose, compressed air is ejected from the head toward the electro-optical device substrate 2. Further, the electro-optical device substrate 2 is covered with an elastic diaphragm, and the air in the space opposite to the side where the electro-optical device substrate 2 is disposed is separated from the two spaces partitioned by the diaphragm. Or a fluid such as a liquid may be supplied. With this configuration, a uniform force can be applied to each of the electro-optical device substrates 2.

  Next, the melted wax 250 is naturally cooled or forcedly cooled to a temperature of 25 ° C. to solidify the wax 250. As a result, as shown in FIG. 5C, the electro-optical device substrate 2 is fixed in the concave portion 220 of the surface plate 210 via the wax 250 with the other surface side 22 facing upward.

Next, a thinning process is performed. For this purpose, the polishing head 280 is disposed above the electro-optical device substrate 2, and the polishing head 280 is rotated around the axis while the platen 210 is rotated at a speed different from that of the polishing head 280. In this state, while supplying a suspension of abrasive grains between the polishing head 280 and the electro-optical device substrate 2 and as indicated by an arrow P, the polishing head 280 is about 150 g / cm ^2. The other side 22 of the electro-optical device substrate 2 is polished at a speed of about 7.2 μm / min while applying a load of 0.5 mm to a thickness of 0.5 to 25 μm (lapping step).

Next, as a polishing step, as shown in FIG. 5D, a soft polishing cloth 281 is attached to the lower end portion of the polishing head 280, and abrasive grains are interposed between the polishing head 280 and the electro-optical device substrate 2. While supplying the suspension as required, and as indicated by an arrow P, while applying a load of about 50 g / cm ² to the polishing head 280, the other surface side of the polished substrate 2 for the electro-optical device The surface of 22 is smoothed. As a result, the electro-optical device substrate 2 has a light transmittance equivalent to that of glass.

  Next, as shown in FIG. 6A, the other surface side 22 of the electro-optical device substrate 2 is cleaned. Next, as shown in FIG. 6B, an adhesive 30 is applied to the other surface side 22 of the electro-optical device substrate 2, and then, as shown in FIG. The large substrate 3 is stacked on the other side 22 and the adhesive 30 is cured. Also in this case, fluid pressure is applied to the large substrate 3 to press the large substrate 3 against the surface plate 210, thereby improving the adhesion between the electro-optical device substrate 2 and the large substrate 3. As a method for applying fluid pressure to the large substrate 3, for example, compressed air is ejected from the head toward the large substrate 3. Further, a diaphragm having elasticity is placed on the large substrate 3, and a fluid such as air or liquid is put into a space opposite to the side where the large substrate 3 is disposed, in the two spaces partitioned by the diaphragm. You may supply. In this way, the fluid pressure is applied to the large substrate 3 and the large substrate 3 is pressed against the surface plate 210 to bond the electro-optical device substrate 2 and the large substrate 3 together. A uniform force is applied to the substrate 2. Accordingly, any of the electro-optical device substrates 2 can be bonded to the large substrate 3 under the same conditions. Therefore, it is possible to prevent variations in position in the thickness direction of the electro-optical device substrate 2 in a state in which the organic EL display device 1 is formed, so that high quality images can be displayed.

  In this manner, the plurality of electro-optical device substrates 2 are bonded to the large substrate 3 on the surface plate 210 via the adhesive 30 to form the bonded substrate 10, and the solidified wax 250 is then used. The substrate 2 for electro-optical device (bonded substrate 10) is melted by heating to a temperature of about 80 ° C. indirectly or directly through the surface plate 210, as shown in FIG. 6 (D). Remove from the recess 220 of the platen 210.

  Next, the protective film 6 is irradiated with UV light, and the protective film 6 is peeled off as shown in FIG. At this time, since the protective film 6 is a UV film, the adhesive material layer 63 is completely removed from the one surface side 21 of the electro-optical device substrate 2 when irradiated with UV light. As described above, in this embodiment, since the bonding process is performed in a state where the protective film 6 is adhered to the one surface side 21 of the electro-optical device substrate 2, the adhesion of foreign matters and the external force during the thinning process and the bonding process are performed. It is possible to prevent the TFTs 123 and 124 from being damaged. In addition, since the bonding process is performed in a state where the protective film 6 is adhered to the one surface side 21 of the electro-optical device substrate 2, the electro-optical device substrate 2 is directed toward the surface plate 210 with the one surface side 21 facing the surface plate 210. Even if the device substrate 2 is arranged and bonded to the large substrate 3, adhesion or damage of foreign matter does not occur on the one surface side 21 of the electro-optical device substrate 2.

  In this manner, after the bonded substrate 10 shown in FIG. 7A is manufactured, a light emitting functional layer forming step is performed. For this purpose, holes are directed toward the region surrounded by the partition wall 112 in the electro-optical device substrate 2 while relatively moving the inkjet head 9 and the electro-optical device substrate 2 indicated by a one-dot chain line in FIG. After selectively discharging and applying a liquid composition for forming the injection / transport layer 110a, heat treatment is performed to form the hole injection / transport layer 110a. Similarly, while the inkjet head 9 and the electro-optical device substrate 2 are moved relative to each other, the light-emitting layer 110b corresponding to a predetermined color is formed in the region surrounded by the partition 112 in the electro-optical device substrate 2. After the liquid composition is discharged and applied, heat treatment is performed to form the light emitting layer 110b. Here, the liquid composition for forming the hole injection / transport layer 110a is composed of 3,4-polyethylenediosithiophene / polystyrene sulfonic acid (PEDOT / PSS), a conductive polymer such as polyaniline, polypyrrole, MTDATA, A solution or dispersion of a phenylamine derivative, copper phthalocyanine, or the like. The liquid composition for forming the light emitting layer 110b includes (poly) fluorene derivative (PF), (poly) paraphenylene vinylene derivative (PPV), polyphenylene derivative (PP), polyparaphenylene derivative (PPP), and polyvinyl. These are solutions or dispersions of polysilanes such as carbazole (PVK), polythiophene derivatives, and polymethylphenylsilane (PMPS).

  As described above, in this embodiment, processes that require laser annealing, photolithography technology, and the like, such as the formation of TFTs 123 and 124 and the formation of the pixel electrode 111, are performed before the bonding process to the large substrate 3, and the bonding process. Thereafter, when the light emitting functional layer 110 of the organic EL element 101 is formed, an ink jet method that can be easily applied to an arbitrary position is employed. For this reason, even when the light emitting functional layer 110 of the organic EL element 101 is formed in a wide region in which a plurality of electro-optical device substrates 2 are arranged in a plane, the size of the manufacturing apparatus is not increased and the yield is not reduced. . In addition, since the lamination with the large substrate 3 is performed on the basis of the one surface side 21 on which the protective film 6 of the substrate 2 for the electro-optical device is formed, an inkjet head is formed when the light emitting functional layer 110 is formed by the inkjet method. The distance from 9 to the one surface side 21 of the electro-optical device substrate 2 is constant in any electro-optical device substrate 2. Therefore, since the flying distance of the droplets from the ink jet head 9 is constant in any electro-optical device substrate 2, it is possible to prevent variations in the formation position and luminance of the light emitting functional layer 110 due to variations in the flying distance. Can do.

  Next, as shown in FIG. 3, a calcium layer 12a and an aluminum layer 12b are sequentially formed by vapor deposition or the like. At that time, without using a large manufacturing apparatus, the outer peripheral portion such as the terminal formation region is covered with a predetermined member for the purpose of selectively forming the calcium layer 12a and the aluminum layer 12b over a wide area. Vapor deposition is performed.

  Next, as shown in FIG. 8A, a sealing substrate 4 that is equal to or larger than the plurality of electro-optical device substrates 2 is placed on one surface side of the electro-optical device substrate 2 with a sealing resin 40 interposed therebetween. 21 to form a panel 1 ′. As a result, as shown in FIG. 9A, the terminals 20 formed on the electro-optical device substrate 2 are covered with the sealing substrate 4.

  Next, in the polishing apparatus 200 described with reference to FIG. 5C and the like, the panel 1 'is thinned. First, as shown in FIG. 8B, the panel 1 ′ is fixed on the surface plate 210 of the polishing apparatus 200 with the sealing substrate 4 facing upward (fixing step). For this purpose, the wax 250 is heated and melted to a temperature of about 80 ° C. indirectly or directly via the surface plate 210, and then a large substrate is placed on the surface of the melted wax 250 toward the surface plate 210. The panel 1 ′ is disposed with the 3 facing, and a fluid pressure is applied to the panel 1 ′ to press the panel 1 ′ into the recess 220. At that time, compressed air is ejected from the head toward the panel 1 ′. In addition, an elastic diaphragm is placed on the panel 1 ′, and a fluid such as air or liquid is placed in the space opposite to the side where the panel 1 ′ is disposed, of the two spaces partitioned by the diaphragm. What is necessary is just to supply. With this configuration, a uniform force can be applied to each of the electro-optical device substrates 2.

  Next, the melted wax 250 is naturally cooled or forcedly cooled to a temperature of 25 ° C. to solidify the wax 250. As a result, the panel 1 ′ is fixed through the wax 250 in the recess 220 of the surface plate 210 with the sealing substrate 4 facing upward.

Next, a thinning process is performed. For this purpose, the polishing head 280 is disposed above the panel 1 ′, and the polishing head 280 is rotated around the axis while the platen 210 is rotated at a speed different from that of the polishing head 280. While supplying a suspension of abrasive grains between the polishing head 280 and the panel 1 ′ and applying a load of about 150 g / cm ² to the polishing head 280 as indicated by an arrow P, The surface of the sealing substrate 4 of the panel 1 ′ is polished at a speed of about 7.2 μm / min to reduce the thickness from 0.5 mm to 25 μm (lapping process).

Next, as a polishing step, as shown in FIG. 8C, a soft polishing cloth 281 is attached to the lower end of the polishing head 280, and a suspension of abrasive grains is provided between the polishing head 280 and the panel 1 ′. Is supplied as necessary, and as indicated by an arrow P, the surface of the sealing substrate 4 is smoothed while applying a load of about 50 g / cm ² to the polishing head 280. Thereby, the sealing substrate 4 has a light transmittance equivalent to that of glass.

  Thereafter, the solidified wax 250 is melted by heating to a temperature of about 80 ° C. indirectly or directly through the surface plate 210, and the panel 1 ′ is removed from the surface plate 210.

  Further, in the case of reducing the thickness of the large-sized substrate 3, as shown in FIG. 8D, the large-sized substrate 3 is turned upward as in the method described with reference to FIGS. 8B and 8C. Then, the panel 1 'is arranged and fixed on the surface plate 210 of the polishing apparatus 200, and then the surface of the large substrate 3 is polished to thin the large substrate 3 to a thickness of 0.5 mm to 25 μm (lapping step). Further, as shown in FIG. 8E, the surface of the large substrate 3 is smoothed (polishing step), and then the panel 1 ′ is removed from the surface plate 210.

  Then, after cleaning the panel 1 ′, as shown in FIG. 9B, the large substrate 3 is cut by irradiating a laser to adjust the large substrate 3 to a predetermined size.

  Next, as shown in FIG. 9C, the sealing substrate 4 is cut by irradiating a laser to adjust the sealing substrate 4 to a predetermined size. As a result, the terminals 20 formed on the electro-optical device substrate 2 are exposed. Then, as shown in FIG. 9D, the flexible wiring board 7 on which the IC 70 is COF mounted is connected to the terminal 20.

  When the present invention is applied to a panel made of a single electro-optical device substrate 2, the bonding of the large substrate 3, the thinning of the large substrate 3, and the cutting of the large substrate 3 are omitted. This leads to (D) of FIG.

(Main effects of this form)
As described above, in this embodiment, when the panel 1 ′ is thinned, the panel 1 ′ is thinned in a state where the counter substrate 4 and the large substrate 3 are bonded to the electro-optical device substrate 2, Until then, both the counter substrate 4 and the large substrate 3 are thick. Therefore, even when a hard substrate such as a glass substrate is used as the counter substrate 4 or the large substrate 3 and the counter substrate 4 and the large substrate 3 are thinned to, for example, 100 μm or less, and further to 50 μm or less, the manufacturing process is in progress. The counter substrate 4 and the large substrate 3 are not likely to break.

  Further, since the thinning in the state of the panel 1 ′ is performed not by chemical etching but by polishing, the terminals 20 formed on the electro-optical device substrate 2 are not etched. Furthermore, since the terminal 20 is covered with the counter substrate 4 during polishing, the terminal 20 is not damaged.

  Furthermore, since the panel 1 ′ is fixed on the surface plate 210 with the wax 250 at the time of polishing, the panel 1 ′ can be removed from the surface plate 210 simply by melting the wax 250 after the polishing is completed. In addition, if the fixing is performed using the wax 250, the fixing stress does not concentrate on a part of the panel 1 ', so that the panel 1' is not cracked. In addition, since the wax 250 melts at a temperature of about 80 ° C., the organic EL material does not deteriorate even if the panel 1 ′ holds the organic EL material.

  Further, since the panel 1 'is fixed to the surface plate 210 by applying fluid pressure, a uniform force can be applied to the entire panel 1'. Therefore, the panel 1 ′ can be fixed on the surface plate 210 with an appropriate posture, and polishing can be performed with high accuracy.

[Modification of Embodiment 1]
As shown in FIG. 10, as the protective film 6 used in the steps shown in FIGS. 4A and 4B, a UV film provided with a pressure-sensitive adhesive layer 63 thicker than the partition 112 on the film base 61 is used. When the protective film 6 is attached to the one surface side 21 of the electro-optical device substrate 2, it is possible to prevent bubbles from entering between the electro-optical device substrate 2 and the protective film 6. Therefore, since the surface of the protective film 6 is not uneven due to air bubbles, when the electro-optical device substrate 2 and the large substrate 3 are bonded together, the position of the one surface side 21 of the electro-optical device substrate 2 is high. Can be aligned with accuracy. Therefore, the light emitting functional layer 110 can be stably formed by the inkjet method, and position variation in the thickness direction of the electro-optical device substrate 2 in the state where the organic EL display device 1 is configured can be prevented. Therefore, a high quality image can be displayed.

  Further, as shown in FIG. 11 (A), the protective film 6 is provided with a liquid repellent material layer 64 for the liquid composition for forming the light emitting functional layer 110 in the film base 61 and an adhesive. If the layer 63 is made thinner than the height of the partition 112, when the protective film 6 is removed, as shown in FIG. 11B, the periphery of the liquid composition application region in the ink jet method, that is, the partition 112. The liquid repellent material layer 64 can be transferred to the upper end side. Accordingly, it is not necessary to perform special liquid repellent treatment such as plasma treatment using a fluorine compound on the one surface side 21 of the electro-optical device substrate 2, so that the manufacturing process can be simplified.

  In the above embodiment, the organic EL display device 1 is taken as an example. However, the present invention may be applied to the manufacture of a self-luminous electro-optical device using other self-luminous elements.

[Embodiment 2]
The first embodiment is an example in which the present invention is applied to an organic EL display device in which an electro-optical material is held on a single substrate for an electro-optical device, but as shown in FIGS. 12 (A) and 12 (B). In addition, the present invention may be applied to a liquid crystal display device in which an electro-optic material is held between two electro-optic device substrates.

  12A and 12B are a perspective view and a cross-sectional view of the liquid crystal panel according to Embodiment 2 of the present invention as viewed from the counter substrate side.

  As shown in FIGS. 12A and 12B, in the liquid crystal panel 500, a TFT array substrate 510 (electro-optical device substrate) and a counter substrate 520 bonded together by a sealing material 552 applied in a rectangular frame shape. A liquid crystal 550 as an electro-optical material is held therebetween. The TFT array substrate 510 is larger than the counter substrate 520, and a large number of terminals 514 are formed along one side of the TFT array substrate 510 in the protruding region 512 from the counter substrate 520. Note that the driving IC may be COG-mounted on the TFT array substrate 510. Even in such a case, the terminal 514 is formed in the overhanging region 512.

  On the TFT array substrate 510, pixel electrodes 559 are formed in a matrix along with pixel switching TFTs. On the counter substrate 520, a light shielding film 523 called a black matrix or black stripe is formed in a region facing the vertical and horizontal boundary regions of the pixel electrode 559 of the TFT array substrate 510, and an ITO film is formed on the upper layer side. The counter electrode 521 is formed. In the case where the liquid crystal panel 500 is configured for color display, an RGB color filter is formed together with its surface protective film in a region of the counter substrate 520 facing each pixel electrode 559 of the TFT array substrate 510.

  Also in the liquid crystal panel 500 having such a configuration, when the TFT array substrate 510 and the counter substrate 520 are thinned, the TFT array substrate 510 and the counter substrate 520 are bonded to form a panel, see FIG. The thickness is reduced by the method described above. At that time, as shown by a one-dot chain line in FIG. 12B, the terminal 514 of the TFT array substrate 510 is covered with the counter substrate 520 by using the counter substrate 520 having substantially the same size as the TFT array substrate 510. After finishing the thinning, the end of the counter substrate 520 is cut with a laser to expose the terminal 514.

  Further, similarly to the organic EL display device 1 shown in Embodiment Mode 1, a large liquid crystal display device can be formed from a plurality of liquid crystal panels 500. That is, after the liquid crystal panel 500 of FIG. 12 is completed, the protective film 6 is attached to the counter substrate 520 side as in FIG. 5A, and a plurality of liquid crystal panels are placed on the surface plate 210 of the polishing apparatus 200 with the protective film surface down. 500 is arranged and fixed with wax 250. In other words, each process may be followed with the electro-optical device substrate 2 'in FIG. After thinning the TFT array substrate 510 in this way, the large substrate 3 is bonded to the TFT array substrate 510 side in the same way as in FIG. 6, and a large-sized liquid crystal panel as shown in FIG. Complete the display panel. However, since the counter substrate 520 remains thick at this stage, the counter substrate 520 is then thinned according to the process of FIG. The process at this time is exactly the same as in the first embodiment, and the organic EL display device 1 ′ in FIG. 8 may be replaced with a liquid crystal panel 500 in which only the TFT array substrate 510 is thinned. After the thinning of the counter substrate 520 is completed, the end of the counter substrate 520 is laser-cut in accordance with the process of FIG. 9, and the flexible substrate 7 is attached to the exposed terminals.

(Main effects of this form)
As described above, in this embodiment, a small to large panel in which one or a plurality of liquid crystal panels 500 are arranged in a plane can be efficiently thinned. That is, in the case of a small panel, a plurality of panels can be simultaneously thinned, and in the case of a large panel in which a plurality of small substrates are bonded together, a large area can be thinned collectively.

  Further, since the thinning of the liquid crystal panel 500 is performed by polishing instead of chemical etching, the terminals 514 formed on the TFT array substrate 510 are not etched. Further, since the terminal 514 is covered with the counter substrate 520 during polishing, the terminal 514 is not damaged.

  Furthermore, since the liquid crystal panel 500 is fixed on the surface plate 210 with the wax 250 during polishing, the liquid crystal panel 500 can be removed from the surface plate 210 simply by melting the wax 250 after the polishing is completed. In addition, if the fixing is performed using the wax 250, the fixing stress does not concentrate on a part of the liquid crystal panel 500, so that the panel is not cracked. Further, since the wax 250 melts at a temperature of about 80 ° C., the material does not deteriorate even if the liquid crystal panel 500 holds the liquid crystal material.

  Further, since fluid pressure is applied to the liquid crystal panel 500 and fixed to the surface plate 210, a uniform force can be applied to the entire panel. Therefore, the liquid crystal panel 500 can be fixed on the surface plate 210 with an appropriate posture, and polishing with high accuracy can be performed.

[Application to electronic devices]
The electro-optical device to which the present invention is applied is a multimedia-compatible personal computer (PC), mobile computer, engineering workstation (EWS), pager, or mobile phone, word processor, TV, viewfinder type or monitor direct view type. In addition to being applicable to electronic devices such as video recorders, electronic notebooks, electronic desk calculators, car navigation devices, POS terminals, touch panels, etc., they are mounted on electronic devices having a large screen exceeding 30 inches.

FIGS. 2A and 2B are a perspective view and a plan view of an active matrix organic EL display device which is an embodiment of the self-luminous electro-optical device according to Embodiment 1 of the present invention. FIGS. It is explanatory drawing which shows the electrical structure of the organic electroluminescent display apparatus shown in FIG. It is sectional drawing which expands and shows the pixel area | region in the organic electroluminescent display apparatus shown in FIG. (A), (B) is explanatory drawing of the stage which finished forming TFT and a pixel electrode with respect to the substrate for electro-optical devices in the manufacturing method of the organic electroluminescence display shown in FIG. (A)-(D) are process sectional drawings which showed the process of thinning the board | substrate for electro-optical apparatuses. FIGS. 9A to 9E are process cross-sectional views illustrating a process of bonding a plurality of electro-optical device substrates to a large substrate. (A), (B) is explanatory drawing of the organic functional layer formation process in the manufacturing method of the organic electroluminescence display shown in FIG. (A)-(E) are process sectional drawings which show the process of thinning a panel among the manufacturing processes of a display apparatus. (A)-(D) are explanatory drawings which show the process of connecting a flexible wiring board to a terminal while cut | disconnecting a rear-end part thinning a panel among the manufacturing processes of a display apparatus. It is explanatory drawing of the state which stuck the protective film on the board | substrate for electro-optical devices in the manufacturing method of another organic electroluminescence display which concerns on this invention. (A), (B) is explanatory drawing of the state which stuck the protective film on the board | substrate for electro-optical devices in the manufacturing method of another organic electroluminescent display device which concerns on this invention. (A), (B) is the perspective view and sectional drawing of the liquid crystal device which concern on Embodiment 2 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL display device (electro-optical device), 1 ′ panel, 2 electro-optical device substrate (TFT array substrate), 3 large substrate, 4 sealing substrate (counter substrate), 6 protective film, 9 inkjet head, 20, 514 terminal, 101 organic EL element, 110 light emitting functional layer, 111 pixel electrode, 123, 124 TFT, 200 polishing device, 210 surface plate, 220 concave portion of surface plate, 250 wax, 280 polishing head, 500 liquid crystal device (electro-optical) Device), 510 TFT array substrate (substrate for electro-optical device), 520 counter substrate.

Claims (9)

In the panel in which the terminal of the substrate for the electro-optical device is formed and the one surface side is bonded to the counter substrate and the terminal is covered with the counter substrate,
A fixing step of fixing the panel on a surface plate with wax;
A thinning process for polishing and thinning the panel;
A method of manufacturing an electro-optical device, comprising: a cutting step of cutting the counter substrate to expose the terminals.   2. The wrapping process according to claim 1, wherein in the thinning process, the panel is polished and thinned while the panel is fixed on the surface plate with the wax, and the surface of the panel polished in the wrapping process. A method for manufacturing an electro-optical device, comprising: performing a polishing step for smoothly polishing the substrate.   3. The fixing process according to claim 1, wherein in the fixing step, the wax is heated and melted in a recess formed on the upper surface of the surface plate, the panel is immersed in the melted wax, and the panel is immersed in the panel. A method of manufacturing an electro-optical device, wherein fluid pressure is applied and pressed toward the surface plate, and then the wax is cooled and solidified to fix the panel.   2. The method of manufacturing an electro-optical device according to claim 1, wherein, in the cutting step, the counter substrate is cut by a laser.   4. The method of manufacturing an electro-optical device according to claim 1, wherein the panel includes one or more electro-optical device substrates bonded to the counter substrate.   6. The method of manufacturing an electro-optical device according to claim 1, wherein the electro-optical device substrate holds an electroluminescent material as an electro-optical material on the one surface side.   6. The electro-optical device according to claim 1, wherein the electro-optical device substrate holds a liquid crystal as an electro-optical material between the one surface side and the counter substrate. Production method.   An electro-optical device manufactured by the method defined in claim 1. An electronic apparatus comprising the electro-optical device defined in claim 8.

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