JP2011128224A - Method for manufacturing display device, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a display device, the method easily, adequately exposing an electrode for connecting an external circuit when a display device is manufactured; and to provide a display device. <P>SOLUTION: The method for manufacturing a display device has a process in which after two base boards are bonded together by a sealing agent, the boards are cut into individual pieces, and an electrode on the surface on the bonding side of one base board is exposed by cutting and removing the other base board. In this case, a laser light-shielding member is arranged between a part facing the electrode and the other base board, and the other base board is irradiated with laser light, at the part facing the electrode, to be cut off, and the laser light, which is radiated when the cutting is made, is shielded by the shielding member so that the electrode may not be irradiated with the laser light. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a display device manufacturing method and a display device suitable for manufacturing, for example, a liquid crystal display device using a flexible substrate, an organic EL display device, a particle movement type display device, and the like.

  For example, a liquid crystal display device such as a liquid crystal display panel has features such as thin and light weight and low power consumption, and is widely used. In this liquid crystal display device, a set of two substrates is held at a predetermined interval by a spacer. And sticking together using a sealant. In general, an end of one substrate of the set of two sheets is made larger than the other substrate, and an electrode for connecting an electric circuit from the outside is taken out to this portion.

  For example, glass is generally used for a substrate of a liquid crystal display panel or an organic EL display panel, but a plastic film is used on the substrate in order to enable curved display or to manufacture a further thin and light display panel. The one used is also proposed. When using a glass substrate, when exposing an electrode for connecting an electric circuit from the outside from a panel in which a set of two substrates of the same size are bonded together, a break is formed on the substrate that is not the substrate on which the electrode is provided. And then split along this line. However, for example, when manufacturing a liquid crystal display panel using a plastic film substrate in particular, since the substrate is flexible, it cannot be broken and another method is required.

  Recently, as an efficient cutting method of a liquid crystal display panel formed from substrate materials having different properties such as a glass substrate and a plastic substrate, a method using laser irradiation has been proposed (see Patent Document 1). By utilizing such laser irradiation, it is conceivable to cut a substrate on which no electrode is provided.

JP 2006-343747 A

  Thus, for example, when manufacturing a display device using a plastic film substrate, in order to expose an electrode for connecting an external circuit, one end of one substrate of a set of two substrates is connected to the other. When it is made larger than the substrate and the electrode is taken out to this portion, there is a possibility that a malfunction may occur due to, for example, destruction of the electrode due to the laser irradiation that cuts one substrate hits the electrode of the other substrate.

  The problem to be solved by the present invention is to provide a display device manufacturing method and a display device capable of easily and satisfactorily exposing electrodes for connecting external circuits when manufacturing the display device. That is.

  In order to solve the above-described problems and achieve the object, the present invention is configured as follows.

In the first aspect of the invention, the two substrates are bonded to each other with a sealant and then cut into pieces, and the electrodes on the bonding side surface of one substrate are removed by cutting the other substrate. In the manufacturing method of the display device including the step of exposing,
A member that shields the laser is disposed between the portion facing the electrode and the other substrate,
Cutting the other substrate by irradiating the other substrate with a laser at a portion facing the electrode;
The method of manufacturing a display device, wherein the laser irradiated at the time of cutting is shielded from light so as not to hit the electrode by the light shielding member.

  The invention according to claim 2 is the method for manufacturing a display device according to claim 1, wherein at least the substrate to be cut and removed is a plastic film substrate.

  According to a third aspect of the present invention, in the display according to the first or second aspect, the light shielding member is a layer that shields a laser formed on a bonding side surface of the other substrate. It is a manufacturing method of an apparatus.

  According to a fourth aspect of the present invention, in the display according to the first or second aspect, the light-shielding member is a layer that shields a laser formed on the upper surface of the electrode so as to be peelable. It is a manufacturing method of an apparatus.

  The invention according to claim 5 is characterized in that the light shielding member is a layer for shielding a laser formed on an upper surface of the electrode through an insulating layer. This is a manufacturing method of the display device.

  According to a sixth aspect of the present invention, in the method for manufacturing a display device according to the first or second aspect, the light shielding member is the sealing agent formed on an upper surface of the electrode. is there.

  The invention described in claim 7 is the method for manufacturing a display device according to claim 3 or 4, wherein the layer that shields the laser is a metal layer that shields the laser.

  The invention according to claim 8 is the method for manufacturing a display device according to claim 3 or 4, wherein the layer that shields the laser is a resin layer containing a material that shields the laser. .

  The invention described in claim 9 is the method for manufacturing a display device according to claim 6, wherein the sealant is a resin containing a material that shields laser light.

  The invention described in claim 10 is the method for manufacturing a display device according to any one of claims 1 to 9, wherein the laser is a CO2 laser.

Invention of Claim 11 is manufactured using the manufacturing method of the display apparatus of any one of the said Claim 1 thru | or 10.
The display device has a structure in which two substrates are bonded to each other with a sealant, and one of the substrates is removed to expose an electrode of the other substrate.

  With the above configuration, the present invention has the following effects.

  In the invention according to claim 1, by irradiating the other substrate with a laser at a portion facing the electrode and cutting it, the laser irradiated at the time of cutting is shielded so that it does not hit the electrode by a member that shields light, When manufacturing a display device, an electrode for connecting an external circuit can be easily and satisfactorily exposed.

  In the invention described in claim 2, at least the substrate to be cut and removed is a plastic film substrate, which enables curved display or manufacture of a thin and light display panel. .

  In the invention described in claim 3, the light shielding member is a layer that shields the laser formed on the bonding side surface of the other substrate, and can be easily and reliably disposed at a predetermined position on the other substrate.

  In the invention according to claim 4, the light shielding member is a layer that shields the laser formed on the upper side surface of the electrode so as to be peelable, and can easily and reliably protect the electrode.

  In the invention described in claim 5, the light shielding member is a layer that shields the laser formed on the upper surface of the electrode via the insulating layer, and can easily and reliably protect the electrode, and also shield the light. The member can be used as it is without peeling off.

  In the invention described in claim 6, the light shielding member is a sealing agent formed on the upper side surface of the electrode, and the manufacturing cost can be reduced by using the sealing agent.

  According to the seventh aspect of the present invention, since the layer that shields the laser is a metal layer that shields the laser, the light can be shielded easily and reliably.

  In the invention described in claim 8, the light shielding layer can be easily and reliably shielded by being a resin layer containing a material that shields the laser.

  In invention of Claim 9, since a sealing agent is resin containing the material which shields a laser, it can shield easily and reliably.

In the invention described in claim 10, since the laser is a CO2 laser, high-precision cutting is possible with an inexpensive and simple structure.
The invention described in claim 11 is manufactured using the method for manufacturing a display device according to any one of claims 1 to 10 and has a structure in which two substrates are bonded together with a sealant. By removing one of the substrates and exposing the electrodes of the other substrate, the quality of the manufactured display device is guaranteed.

It is a top view of the board | substrate which provided the site | part which act | operates by a sealing agent and electricity. It is a figure which shows the state which bonded together 2 board | substrates with the sealing compound. It is a figure which shows the process to cut | disconnect. 7 is a cross-sectional view illustrating the method for manufacturing the display device of the first embodiment. FIG. It is sectional drawing explaining the manufacturing method of the display apparatus of 2nd Embodiment. It is sectional drawing explaining the manufacturing method of the display apparatus of 3rd Embodiment. It is sectional drawing explaining the manufacturing method of the display apparatus of 4th Embodiment. It is sectional drawing explaining the manufacturing method of the display apparatus of 5th Embodiment. It is a perspective view of the display device. It is a top view of a display apparatus. It is sectional drawing of a display apparatus.

  Hereinafter, a display device manufacturing method and a display device according to embodiments of the present invention will be described. The embodiment of the present invention shows the most preferable mode of the present invention, and the present invention is not limited to this.

  A method of manufacturing the display device according to this embodiment will be described with reference to FIGS. 1 is a plan view of a substrate provided with a sealing agent and a part that is operated by electricity, FIG. 2 is a diagram showing a state in which two substrates are bonded together with the sealing agent, FIG. 3 is a diagram showing a cutting process, and FIG. 8 to 8 are cross-sectional views for explaining a method for manufacturing a display device.

  In the manufacturing method of the display device 1, a plurality of display devices 1 are bonded so that the outside of the part 4 that is operated by electricity is surrounded by the first sealant 5a, and the outside of the plurality of display devices 1 is And a cutting process for manufacturing a plurality of display devices 1 individually after manufacturing.

  In the manufacturing process, as shown in FIG. 1, the first sealing agent 5a is applied in a quadrangular shape so as to create individual display devices 1 on a single substrate 2, and the first sealing agent in the rectangular shape. A portion 4 that is actuated by electricity of the individual display device 1 is provided inside 5a, and the first sealant 5a is adhered so as to surround the outside of the portion 4 that is actuated by this electricity.

  Further, the second sealing agent 5b is applied on the substrate 2 so as to surround the entire outside of the portion 4 that is operated by electricity of the plurality of display devices 1, and after the second sealing agent 5b is applied, two sheets are provided. The substrates 2 and 3 are bonded together. By providing the part 4 that operates by electricity, the first sealant 5a, and the second sealant 5b on the same substrate 2, quality control can be performed as one component and rapid manufacturing is possible. is there. Alternatively, the first sealant 5a may be applied on one substrate 2 and the second sealant 5b may be applied on the other substrate 3, and quality control can be performed as separate parts and quickly. Manufacturing is possible.

  In this embodiment, using a dispenser, the liquid first sealing agent 5a and the second sealing agent 5b in a syringe are applied by discharging from the opening of the dispenser. This dispenser uses a dispenser with small variation in the discharge amount of the opening at each position in the width direction of the opening row, and is applied while extruding the liquid first sealing agent 5a and the second sealing agent 5b contained in the syringe. By doing so, the 1st sealing agent 5a and the 2nd sealing agent 5b can be provided simply and reliably.

  The first sealant 5a is provided so as to surround the entire exterior of the parts 4 that are operated by electricity of the plurality of display devices 1, and the second sealant 5b is provided by electricity of the plurality of display devices 1. It has given so that the whole exterior of operation part 4 may be surrounded. The first sealing agent 5a and the second sealing agent 5b are not limited to those that surround the entire exterior, but may be applied so as to surround a part of the exterior.

  For example, a thermosetting resin, a photocurable resin, or the like having a thickness of 2 μm to 10 μm is used as the first sealing agent 5a as long as it is a material that is cured by light and / or heat. As a material that is cured by light and heat, a photocurable / thermosetting resin composition disclosed in JP-A-2004-45792 can be used. This photocurable / thermosetting resin composition comprises (A) a bisphenol polyfunctional epoxy resin (a), a reaction product with an unsaturated monocarboxylic acid (b), a saturated and / or unsaturated polybasic acid. Reaction of an unsaturated monocarboxylic acid (b) with a photocurable resin obtained by reacting an anhydride (c), and (B) a polyfunctional epoxy compound (a ′) having a regular repetition by an ester bond A photocurable resin obtained by reacting a product with a saturated and / or unsaturated polybasic acid anhydride (c), (C) a photopolymerization initiator, (D) an epoxy curing catalyst, (E) a diluent, And (F) an epoxy compound having two or more epoxy groups in one molecule, and obtained by curing a photocurable / thermosetting resin composition by irradiation with active energy rays and / or heating.

  The first sealant 5a is applied to the substrate to a width of, for example, about 1 mm, and prevents the gap between the substrate and the substrate surface, and also prevents the liquid crystal from leaking. Although it does not specifically limit as the 1st sealing agent 5a, For example, what used the base polymer for suitable polymers, such as an acryl-type polymer, a silicone type polymer, polyester, polyurethane, polyamide, polyether, fluorine type, rubber type, etc. Can be used. In particular, a material excellent in transparency, wettability, cohesiveness, heat resistance, moisture resistance and the like, such as an acrylic pressure-sensitive adhesive, is preferable.

  The second sealant 5b may be the same as or different from the first sealant 5a. As a different one, for example, a sealing material composition described in JP-A-10-265547 is used. In the case of a two-pack type composition in which the sealing material is divided into a main agent and a curing agent, this sealing material composition is blended with (a) an aliphatic cyclic epoxy resin containing an aliphatic ester bond in the molecule together with the epoxy resin in the main agent, On the curing agent side, (b) a trifunctional thiol compound is blended together with the epoxy resin curing agent. As a result, the sealing material composition can lower the crosslink density, can give flexibility and flexibility, and provides a cured product that can follow the flexibility of the flexible substrate. Became possible.

  The cutting process is a process of manufacturing the display device 1 by bonding the two substrates 2 and 3 together with the sealing agents 5a and 5b and then cutting them into individual pieces as shown in FIG. Cut with laser. In this cutting step, the electrode 20 on the surface on the bonding side of one substrate 2 is exposed by cutting and removing the other substrate 3, and the structure in which this electrode 20 is exposed is shown in FIGS. In this way, a member 30 that shields the laser is disposed between the portion facing the electrode 20 and the other substrate, and the other substrate 3 is irradiated with the laser at the portion facing the electrode 20 to be cut, and irradiated at the time of cutting. The laser 30 is shielded so as not to hit the electrode 20 by the member 30 that shields the laser.

  In the first embodiment shown in FIG. 4, at least the substrate 3 to be cut and removed among the substrates 2 and 3 is a plastic film substrate, which enables curved display or a further thin and light display panel. Can be manufactured. As shown in FIG. 4A, the light shielding member 30 is a layer 30a for shielding the laser formed on the bonding side surface 3a of the other substrate 3, and is disposed on the other substrate 3 at a portion facing the electrode 20. When cutting by irradiating a laser, as shown in FIG. 4B, the irradiated laser 50 is shielded so that it does not hit the electrode 20 by the layer 30a that shields the laser, and the end of the other substrate 3 is shielded. The part is cut to expose the electrode 20 of the substrate 2.

  The laser shielding layer 30a may be provided simultaneously with the production of the other substrate 3, or may be provided when cutting is performed by irradiating a laser. The layer 30a that shields the laser may be any layer that generally reflects the laser, for example, a layer formed of a material such as gold, silver, copper, aluminum, or resin, such as a gold foil, a silver foil, or a copper foil. Aluminum foil, silver paste, etc. are used. The thickness of the layer 30 a that shields the laser is formed of a film of about 1 μm, for example, and can be easily and reliably disposed at a predetermined position on the other substrate 3. Thus, the layer 30a that shields the laser may be a metal layer that shields the laser or a resin layer containing a material that shields the laser, and can be shielded easily and reliably.

  In the second embodiment shown in FIG. 5, the light shielding member 30 is a layer 30 b that shields a laser formed on the upper surface of the electrode 20 so as to be peeled off, as shown in FIG. When cutting the other substrate 3 by irradiating the other substrate 3 at a portion facing 20, as shown in FIG. 5B, the irradiated laser 50 does not hit the electrode 20 by the layer 30 b that shields the laser. Thus, the electrode 20 can be protected easily and reliably, and the end of the other substrate 3 can be cut. The laser shielding layer 30 b is configured in the same manner as the laser shielding layer 30 a of the embodiment shown in FIG. 4, but can be peeled off in order to connect an external circuit to the electrode 20.

  In the third embodiment shown in FIG. 6, the light shielding member 30 is a layer 30c that shields a laser formed on the upper surface of the electrode 20 via an insulating layer 31, as shown in FIG. 6 (a). Yes, when the other substrate 3 is irradiated with a laser at a portion facing the electrode 20 and cut, as shown in FIG. 6B, the irradiated laser 50 is separated from the electrode 20 by a layer 30c that shields the laser. Therefore, the electrode 20 can be protected easily and reliably, and the end portion of the other substrate 3 can be cut. The laser shielding layer 30c is configured in the same manner as the laser shielding layer 30a of the embodiment shown in FIG. 4, but when an external circuit is connected to the electrode 20, an insulating layer is formed on the upper surface of the electrode 20. The layer 30c that shields the laser and can be used as it is without being peeled off.

  In the fourth embodiment shown in FIG. 7, the light shielding member 30 is a sealing agent 5 c formed on the upper surface of the electrode 20 as shown in FIG. 7A, and this sealing agent 5 c is the electrode 20. When the other substrate 3 is cut by irradiating a laser at a portion facing the substrate, the irradiated laser 50 is shielded from light so as not to hit the electrode 20 by a sealing agent 5c, as shown in FIG. 7B. The electrode 20 can be protected easily and reliably, and the end of the other substrate 3 can be cut. This sealant 5c is provided separately from the first sealant 5a, but in the fifth embodiment shown in FIG. 8, the first sealant 5a is widened and formed on the upper surface of the electrode 20. Yes.

  The sealing agent 5c and the first sealing agent 5a are, for example, a resin containing carbon or the like and containing a material that shields the laser, so that it can be shielded easily and reliably. In the embodiment shown in FIGS. 7 and 8, the light shielding member 30 is a sealing agent formed on the upper side surface of the electrode 20, and the manufacturing cost can be reduced by using the sealing agent.

  As the laser, for example, it is preferable to irradiate a pulse laser, and in addition to being capable of cutting with high precision, even when one substrate is made of glass, it is difficult to store heat, so that the occurrence of defects due to cracks is small. Further, a CO2 laser can be used as the pulse laser, and high-precision cutting is possible with an inexpensive and simple structure. The CO2 laser is preferable because the processing speed can be increased as compared with the UV laser and the YAG laser.

  In this laser processing, a semiconductor laser, a CO2 laser, a UV laser, a YAG laser, or the like is used, and wavelengths of 10600 nm, 1064 nm, 532 nm, 355 nm, and 266 nm can be used. When the substrate is a transparent material, ultraviolet rays are effective, so 355 nm and 266 nm are used. In the case of using a UV laser, aluminum is effective as a blocking material. That is, when a CO2 laser is used, it is blocked using a material such as copper, aluminum, gold, or silver, and when an ultraviolet laser is used, it is blocked using a material such as aluminum.

  When manufacturing a display device, the other substrate is irradiated with a laser at a part facing the electrode and cut by laser, and the laser irradiated at the time of cutting is shielded so that it does not hit the electrode by a light shielding member. The electrodes for connecting these circuits can be easily and satisfactorily exposed. The substrate on at least the side of the substrate that is cut and removed is a plastic film substrate, which enables curved display or manufacture of a further thin and light display panel. It is manufactured using the manufacturing method of the display device of this embodiment, and has a structure in which two substrates are bonded together with a sealant. One of the substrates is removed, and the electrode of the other substrate is used. By exposing, the quality of the manufactured display device is guaranteed.

  The display device 1 is a variety of devices manufactured by a portion 4 that is operated by electricity. For example, a liquid crystal display device manufactured by holding a liquid crystal between two substrates 2 and 3, and two substrates. Organic EL display device manufactured by forming an electroluminescence layer between 2 and 3, and manufactured by holding particles movable between two substrates 2 and 3, and rewriting display by voltage It is a particle movement type display device that can be used.

  The liquid crystal display device has features such as power saving, light weight, thinness, and the like. As a general liquid crystal display device, an incident side polarizing plate, an output side polarizing plate substrate, and a liquid crystal in a portion that is operated by electricity Those having the following are typical. Compared with a liquid crystal display device, an organic EL display device has many advantageous characteristics as a display such as a high response speed, a wide viewing angle, good visibility unique to a self-luminous element, and a wide temperature range that can be driven. This organic EL display device has a configuration in which a lower electrode, an organic EL layer of a portion that is operated by electricity, and an upper electrode are laminated from the substrate side in each pixel formed on the substrate, and a current is supplied to the organic EL layer. The light from the organic EL, which emits light by flowing, is recognized through at least one of the electrodes (translucent conductive film).

  As a particle movement type display device, a microcapsule type electrophoresis system has been put to practical use as one of display devices using an electrophoresis phenomenon. In this type of display device, positively and negatively charged white particles and black particles are placed in a microcapsule that is electrically operated and filled with a transparent solvent, and each particle is pulled up to the display surface by applying an external voltage. To form an image. There is electronic paper as an example of this particle movement type display device, and electronic paper is a display device in which the display state of the surface is electronically rewritten, and unlike a liquid crystal monitor, a backlight or the like is not used. Compared with an electronic device having another display device, power consumption is reduced. Further, the electronic paper uses power only when the display state of the surface is rewritten, and can maintain the display state of the surface even when power is not supplied. In these display devices 1, the quality of the manufactured display device is guaranteed by removing one of the substrates and exposing the electrodes of the other substrate.

  A display device 100 to which this embodiment is applied will be described with reference to FIGS. 9 is a perspective view of the display device, FIG. 10 is a plan view of the display device, and FIG. 11 is a cross-sectional view of the display device. In the display device 101 of this embodiment, a TFT array substrate 102 and a color filter substrate 103 are bonded together with a sealant 104 interposed therebetween. The seal 104 is provided with a seal spacer 104a to maintain the distance between the TFT array substrate 102 and the color filter substrate 103.

  A polarizing plate 105 is provided on the outer surface of the TFT array substrate 102, and an alignment film 106, a pixel electrode 107, a TFT 108, a signal line 109, and a scanning line 110 are provided on the inner surface. A signal line terminal 111 and a gate line terminal 112 are connected to the signal line 109 and the scanning line 110, respectively. A polarizing plate 120 is provided on the outer surface of the color filter substrate 103, and a color filter portion 121, a black matrix 122, a common electrode 123 made of ITO (Indium-Tin-Oxide), and an alignment film 124 are provided on the inner surface. Yes. Between the TFT array substrate 102 and the color filter substrate 103, a liquid crystal 130, a cell spacer 131, and a transfer electrode 132 are provided.

  In this display device 101, the TFT array substrate 102 and the color filter substrate 103 are bonded together with a sealant 104 and then cut into individual pieces, but the signal wiring terminals of the pixel electrodes 107 on the surface of the TFT array substrate 102 on the bonding side are cut. 111 and the gate wiring terminal 112 are exposed by cutting and removing the other color filter substrate 103. In this cutting, a member 30 that shields the laser is disposed between the portion of the pixel electrode 107 facing the signal wiring terminal 111 and the gate wiring terminal 112 and the other color filter substrate 103, and the signal wiring terminal 111 of the pixel electrode 107. Further, by irradiating the other color filter substrate 103 with a laser at a portion facing the gate wiring terminal 112 and cutting it, the signal wiring terminal 111 and the gate wiring of the pixel electrode 107 by the member 30 that shields the laser irradiated at the time of cutting. The light is shielded so as not to hit the terminal 112.

  The present invention is applicable to a display device manufacturing method and a display device suitable for manufacturing, for example, a liquid crystal display device using a flexible substrate, an organic EL display device, a particle movement type display device, and the like. In manufacturing, an electrode for connecting an external circuit can be easily and satisfactorily exposed.

DESCRIPTION OF SYMBOLS 1 Display apparatus 2, 3 Board | substrate 4 The part 5a which act | operates by electricity 5a 1st sealing agent 5b 2nd sealing agent 5c Sealing agent 20 Electrode 30 Member 30a, 30b, 30c, 30d which shields laser The layer 50 which shields laser A Laser oscillator

Claims (11)

Manufacture of a display device including a step of bonding two substrates together with a sealant and then cutting them into individual pieces, and exposing the electrodes on the bonding side surface of one substrate by cutting and removing the other substrate. In the method
A member that shields the laser is disposed between the portion facing the electrode and the other substrate,
Cutting the other substrate by irradiating the other substrate with a laser at a portion facing the electrode;
A method for manufacturing a display device, characterized in that a laser irradiated at the time of cutting is shielded so as not to hit the electrode by the light shielding member.   The method for manufacturing a display device according to claim 1, wherein at least the substrate on the side to be cut and removed is a plastic film substrate.   The method for manufacturing a display device according to claim 1, wherein the light shielding member is a layer that shields a laser formed on a bonding side surface of the other substrate.   The method for manufacturing a display device according to claim 1, wherein the light shielding member is a layer that shields a laser formed on the upper side surface of the electrode so as to be peelable.   The method for manufacturing a display device according to claim 1, wherein the light shielding member is a layer that shields a laser formed on an upper surface of the electrode via an insulating layer.   The method for manufacturing a display device according to claim 1, wherein the light shielding member is the sealing agent formed on an upper surface of the electrode.   5. The method of manufacturing a display device according to claim 3, wherein the layer that shields the laser is a metal layer that shields the laser.   5. The method for manufacturing a display device according to claim 3, wherein the layer that shields the laser is a resin layer containing a material that shields the laser.   The method for manufacturing a display device according to claim 6, wherein the sealant is a resin containing a material that shields laser light.   The method for manufacturing a display device according to any one of claims 1 to 9, wherein the laser is a CO2 laser. It is manufactured using the method for manufacturing a display device according to any one of claims 1 to 10.
A display device having a structure in which two substrates are bonded to each other with a sealant, and one of the substrates is removed to expose an electrode of the other substrate.