WO2014065171A1

WO2014065171A1 - Bonded substrate manufacturing method

Info

Publication number: WO2014065171A1
Application number: PCT/JP2013/078060
Authority: WO
Inventors: 有希安田; 通園田
Original assignee: シャープ株式会社
Priority date: 2012-10-23
Filing date: 2013-10-16
Publication date: 2014-05-01

Abstract

When bonding an element substrate (30) and an opposing substrate (40) with a sealing material (51) and a filling material (52) interposed therebetween, each of the sealing material (51) and the filling material (52) is applied to a different one of the element substrate (30) and the opposing substrate (40).

Description

Manufacturing method of bonded substrate

This invention relates to the manufacturing method of the bonding board | substrate which bonds an element substrate and a counter substrate through a sealing material and a filler.

In recent years, flat displays have been used in various products and fields. As one of the bonding substrates used for such a flat display, for example, an EL (electroluminescence) display panel is known.

An EL (organic EL, inorganic EL) display panel is an EL element (organic EL element or inorganic EL element) electrically connected to a driving element on a substrate provided with a driving element such as a TFT (thin film transistor). ) Is provided.

The EL element is a light-emitting element capable of high-luminance emission by low-voltage direct current drive, and has a structure in which a first electrode, an EL layer (organic EL layer or inorganic EL layer), and a second electrode are stacked in this order. ing.

In order to protect the EL element from moisture, oxygen, external impact, etc., the EL element is bonded to the counter substrate through a sealing material, by bonding the element substrate on which the EL element is formed, It is sealed between the pair of substrates.

Also, in order to enhance protection, a filler may be enclosed (filled) between the element substrate and the counter substrate.

In some cases, the filler is not sealed. However, when sealing is performed without sealing the filler, when the pair of substrates are bonded together in a vacuum and then returned to atmospheric pressure, the vicinity of the seal portion around the substrate Is held at the same inter-substrate gap as the height of the sealing material, but the inter-substrate gap near the center of the panel cannot be controlled. Therefore, in order to obtain a desired inter-substrate gap over the entire panel, it is preferable that a filler is enclosed between the pair of substrates.

Japanese Patent Publication “Japanese Patent Laid-Open No. 2003-173868 (published on June 20, 2003)”

However, when a filler is sealed between the pair of substrates, there are the following problems. Hereinafter, an organic EL display panel will be described as an example of the EL display panel.

6 (a) and 6 (b) are cross-sectional views showing an example of a method for manufacturing an organic EL display panel in which a filler is enclosed. 6A shows the state before bonding the substrates, and FIG. 6B shows the state after bonding the substrates. Further, in FIGS. 6A and 6B, illustration of components other than the organic EL layer 22 and the sealing film 31 in the element substrate 30 is omitted.

As shown in FIG. 6A, when the element substrate 30 and the counter substrate 40 are bonded together after the filler 52 is applied to the element substrate 30, the structure has a sealing film 31 on the organic EL layer 22. Even if there is a pinhole 111 in the sealing film 31, the filler 52 gradually soaks into the organic EL layer 22 from the pinhole 111. Even if the filler 52 is a curable filler, the solvent contained in the filler 52 soaks into the organic EL layer 22 from the pinhole 111 until the filler 52 is cured.

The solvent of the filler 52 soaked from the pinhole 111 becomes a dark spot as shown in FIG. As described above, when the solvent of the filler 52 soaked from the pinhole 111 is a solvent that damages the organic EL element, it causes deterioration of the element. Such a problem also occurs when the sealing film 31 contains foreign matter.

On the other hand, Patent Document 1 discloses a method for manufacturing an organic EL display panel in which a filler 52 is applied to the counter substrate 40 side.

7A to 7C are cross-sectional views showing the method of manufacturing the organic EL display panel described in Patent Document 1 in the order of steps.

In Patent Document 1, first, as shown in FIG. 7A, a UV (ultraviolet) sealing material is applied as a sealing material 51 on a counter substrate 40 made of a glass substrate or the like to partition a panel region.

Then, as shown in FIG. 7B, after filling the region surrounded by the sealing material 51 with a filler 52 such as silicon oil in a vacuum, as shown in FIG. The element substrate 30 on which the organic EL element 20 is formed is bonded to the counter substrate 40 with a sealing material 51.

Next, after UV irradiation is performed to cure the sealing material 51, the counter substrate 40 is cut for each element substrate 30 to obtain individual organic EL display panels.

However, if the sealing material 51 and the filling material 52 are applied on the same substrate, these materials may influence each other or mix.

In particular, as shown in FIG. 7B, when the filler 52 is applied so as to be blocked by the sealant 51 so that the filler 52 made of a sealing liquid such as silicon oil does not flow out. , The effect appears prominently.

As shown in FIG. 6A, when the sealing material 51 and the filling material 52 are applied on the same substrate even if the filling material 52 is not in contact with the sealing material 51, the sealing material 51 is filled. The material 52 is affected by the solvent atmosphere. As a result, as shown in FIG. 6B, when the element substrate 30 and the counter substrate 40 are bonded to each other even when the filler 52 is not in contact with the seal material 51, the seal material 51 is sealed. Insertion or seal breakage may occur.

It should be noted that the deterioration of the element due to such insertion or breakage of the seal or penetration of the solvent of the filler 52 is more likely as the viscosity of the filler 52 is lower.

However, when a high-viscosity filler is used as the filler 52, the sealing material 51 and the filler 52 are conventionally applied on the same substrate. When the substrates are bonded together, there is a problem that the sealing material 51 is broken by the high-viscosity filler 52 and the sealing property cannot be maintained.

In addition, when the viscosity of the sealing material 51 is increased so that the sealing material 51 is not broken by the high-viscosity filling material 52, the viscosity of the sealing material 51 becomes too high, so that there is a limit in terms of the coating apparatus.

For this reason, there has been a problem in the prior art that it is not possible to use the filler 52 having a very high viscosity.

The present invention has been made in view of the above problems, and its purpose is to suppress seal insertion and seal breakage when bonding an element substrate and a counter substrate through a sealing material and a filler, and element degradation. It is providing the manufacturing method of the bonding board | substrate which can suppress this.

The manufacturing method of the bonding substrate concerning one mode of the present invention is a manufacturing method of the bonding substrate which bonds an element substrate and a counter substrate through a sealing material and a filler, in order to solve the above-mentioned subject, The sealing material and the filler are applied to different substrates of the element substrate and the counter substrate.

According to the method for manufacturing a bonded substrate according to one embodiment of the present invention, the filler is applied until the sealant is cured by applying the sealant and the filler to different substrates of the pair of substrates. It is possible to shorten the time during which is in contact with or close to the sealing material. For this reason, such seal insertion and seal breakage can be prevented.

In addition, when a sealing material and a filler are applied to different substrates of a pair of substrates, any material, for example, when the filler contains a volatile component that causes deterioration of the element, such as The pair of substrates can be attached after removing volatile components.

Especially, in order to prevent deterioration of the element, the element substrate cannot be heated to a very high temperature. However, there is no such limitation on the counter substrate.

For this reason, for example, even when the filler contains a solvent that causes deterioration of the element, such a solvent can be removed before the pair of substrates are bonded together, thereby suppressing deterioration of the element. Can be prevented.

In addition, even when a high-viscosity filler is used as a filler in order to prevent element deterioration, the pair of substrates can be bonded together after the sealing material has a viscosity higher than that of the filler. For this reason, even when a high-viscosity filler is used as the filler, the sealing material can be made highly viscous so that the high-viscosity filler does not break the sealant.

For this reason, according to the manufacturing method of the bonded substrate concerning this embodiment, while sticking an element substrate and a counter substrate via a sealing material and a filler, while suppressing seal insertion and a seal break, Deterioration can be suppressed.

Moreover, according to the manufacturing method of the said bonding board | substrate, a tact up can be aimed at by apply | coating a sealing material and a filler to a mutually different board | substrate.

(A)-(f) is sectional drawing which shows an example of the manufacturing method of the organic electroluminescent display panel concerning Embodiment 1 of this invention in order of a process. It is sectional drawing which shows schematic structure of the principal part of the organic electroluminescence display panel concerning Embodiment 2 of this invention. It is sectional drawing which shows the board | substrate bonding process in the manufacturing method of the organic electroluminescence display panel concerning Embodiment 2 of this invention. (A) * (b) is a figure which shows typically the cross section of the seal | sticker part before and behind bonding of a board | substrate when a sealing material is apply | coated to the element substrate side when wiring is reverse taper shape. (A) * (b) is a figure which shows typically the cross section of the seal | sticker part before and behind bonding of a board | substrate when a sealing material is apply | coated to the opposing board | substrate side when wiring is reverse taper shape. (A) * (b) is sectional drawing which shows an example of the manufacturing method of the organic electroluminescent display panel with which the filler was enclosed. (A)-(c) is sectional drawing which shows the manufacturing method of the organic electroluminescent display panel of patent document 1 in order of a process.

Hereinafter, an embodiment of the present invention will be described in detail.

[Embodiment 1]
This embodiment will be described as follows mainly based on FIGS. 1A to 1F and FIG.

In the present embodiment, an organic EL display panel in an organic EL display device will be described as an example as a bonding substrate according to the present embodiment.

<Schematic configuration of organic EL display panel 1>
FIG. 2 is a cross-sectional view showing a schematic configuration of a main part of the organic EL display panel 1 according to the present embodiment.

As shown in FIG. 2, the organic EL display panel 1 includes an element substrate 30 provided with an organic EL element 20 as an element, a counter substrate 40, a sealing material 51, and a filler 52. The element substrate 30 and the counter substrate 40 are bonded to each other with a sealant 51 and a filler 52 interposed therebetween. The filler 52 is filled in a space surrounded by the pair of substrates including the element substrate 30 and the counter substrate 40 and the sealing material 51.

Before describing the manufacturing method of the organic EL display panel 1 according to the present embodiment, first, the schematic configuration of the element substrate 30 and the counter substrate 40 will be described below together with the materials thereof.

<Schematic configuration of element substrate 30>
The element substrate 30 has a configuration in which the organic EL element 20 is provided on a semiconductor substrate such as a TFT (thin film transistor) substrate. Hereinafter, in this embodiment, a case where the TFT substrate 10 is used as a semiconductor substrate will be described as an example.

(Configuration of TFT substrate 10)
As shown in FIG. 2, a TFT substrate 10 is formed on a base substrate 11 such as a glass substrate, a TFT 12 as a driving element, a signal line 13 (wiring) such as a gate line and a source line for driving the TFT 12, and an interlayer insulation. The film 14, the first electrode 21 in the organic EL element 20, the edge cover 15, and the like are formed.

The edge cover 15 is an insulating layer for preventing the first electrode 21 and the second electrode 23 in the organic EL element 20 from being short-circuited at the end portion of the first electrode 21, and is an organic layer constituting each pixel 2. It also functions as an element isolation film that partitions the EL element 20.

The edge cover 15 is formed on the interlayer insulating film 14 so as to cover the end of the first electrode 21, and the first electrode 21 is exposed in the opening 15 a of the edge cover 15.

The organic EL element 20 uses the opening 15a of the edge cover 15 (that is, the portion where the first electrode 21 is exposed) as the light emitting region 3 of each organic EL element 20, and the organic EL layer 22 and the organic EL layer 22 on the first electrode 21. It is produced by forming the second electrode 23.

The organic EL display panel 1 is, for example, a full-color active matrix organic EL display panel. On the TFT substrate 10, for example, light emission regions of various colors such as red (R), green (G), and blue (B). The pixels 2 of each color composed of the organic EL elements 20 having 3 are arranged in a matrix. A region other than the light emitting region 3 in the pixel 2 is a non-light emitting region 4.

The interlayer insulating film 14 is provided with a contact hole 13 a for electrically connecting the first electrode 21 in the organic EL element 20 to the TFT 12. Thereby, the TFT 12 is electrically connected to the organic EL element 20 through the contact hole 13a.

(Configuration of organic EL element 20)
The organic EL element 20 is a light emitting element that can emit light with high luminance by low voltage direct current drive, and a first electrode 21, an organic EL layer 22, and a second electrode 23 are laminated in this order.

The organic EL layer 22 may be a single-layer type including only a light-emitting layer, or may be a multilayer type including a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and the like. There may be.

When the first electrode 21 is an anode and the second electrode 23 is a cathode, as the organic EL layer 22 from the first electrode 21 side, for example, a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer The electron injection layer and the like are stacked in this order, and the second electrode is formed thereon.

The first electrode 21 injects (supply) holes into the organic EL layer 22, and the second electrode 23 injects (supply) electrons into the organic EL layer 22. Note that the layers between the first electrode 21 and the second electrode 23 are collectively referred to as an organic EL layer.

In the organic EL layer 22, a single layer may have two or more functions. For example, the hole injection layer and the hole transport layer may be formed as independent layers as described above, or may be provided integrally with each other as the hole injection layer / hole transport layer. . Similarly, the electron transport layer and the electron injection layer may be formed as layers independent from each other as described above, or may be integrally provided as an electron transport layer / electron injection layer.

Further, if necessary, a carrier blocking layer or the like for blocking the flow of carriers such as holes and electrons may be appropriately inserted. For example, by adding a hole blocking layer as a carrier blocking layer between the light emitting layer and the electron transporting layer, it is possible to prevent holes from escaping to the electron transporting layer and to improve the light emission efficiency. Similarly, by adding an electron blocking layer as a carrier blocking layer between the light emitting layer and the hole transport layer, it is possible to prevent electrons from escaping to the hole transport layer.

Note that the stacking order is that in which the first electrode 21 is an anode and the second electrode 23 is a cathode. When the first electrode 21 is a cathode and the second electrode 23 is an anode, the stacking order of the organic EL layers 22 is reversed.

Further, the configuration of the organic EL element 20 is not limited to the above-described exemplary layer configuration, and a desired layer configuration can be adopted according to the required characteristics of the organic EL element 20.

The organic EL display panel 1 may be a bottom emission type that emits light from the element substrate 30 side or a top emission type that emits light from the counter substrate 40 side. The bottom emission type organic EL element 20 is formed by using the first electrode 21 as a transparent electrode or a semi-transparent electrode and the second electrode 23 as a reflective electrode. On the other hand, the top emission type organic EL element 20 is formed by using the first electrode 21 as a reflective electrode and the second electrode 23 as a transparent electrode or a semi-transparent electrode.

The reflective electrode may be composed of a single layer or may have a laminated structure of a reflective electrode layer and a transparent electrode layer.

As the transparent electrode material used for the transparent electrode or the transparent electrode layer, ITO (indium tin oxide), IZO (indium zinc oxide), gallium-doped zinc oxide (GZO), or the like can be used.

On the other hand, as the translucent electrode, for example, a metal translucent electrode alone or a laminate of a metal translucent electrode layer and a transparent electrode layer can be used.

Further, as the reflective electrode or the reflective electrode layer, a conductive metal material such as Al (aluminum) or Ag (silver) is used.

(Sealing film 31)
Further, as a protective film for protecting the element, for example, oxygen and moisture enter the organic EL element 20 from the outside so as to cover the second electrode 23 on the second electrode 23. A sealing film 31 is provided to prevent this. Thereby, for example, the organic EL layer 22 can be protected from moisture entering from the contact interface with the sealing material 51.

The sealing film 31 may have a single layer or a laminated structure of an inorganic film, or may have a laminated structure of an inorganic film and an organic film.

Examples of the inorganic film include films made of inorganic materials such as Si (silicon), Al oxides (SiO ₂ , Al ₂ O _3, etc.) and nitrides (SiNx, SiCN).

Further, examples of the organic film include films made of organic materials such as acrylate, polyurea, parylene, polyimide, polyamide, and the like.

<Schematic configuration of counter substrate 40>
The counter substrate 40 is used as a so-called sealing substrate that encapsulates the organic EL element 20 by being disposed opposite to the element substrate 30 via the sealing material 51 and the filler 52.

In addition, when the organic EL display panel 1 is a top emission type, the counter substrate 40 may have a configuration in which a CF (color filter) layer is formed on a base substrate. On the other hand, when the organic EL display panel 1 is a bottom emission type, a CF layer may be formed on the element substrate 30 side. Thus, when using a CF layer together with the organic EL element 20, the spectrum of the light emitted from the organic EL element 20 can be adjusted by the CF layer.

As a base substrate used for the element substrate 30 and the counter substrate 40, for example, a glass substrate or a plastic substrate can be used. An example of the base substrate is a transparent insulating substrate such as an alkali-free glass substrate.

However, the present invention is not limited to this, and an opaque material such as a metal plate can also be used as the substrate on the side that does not emit light.

Next, the sealing material 51 and the filling material 52 used in the present embodiment will be described.

<Sealant 51>
As the sealing material 51, a well-known sealing material used for bonding of substrates, such as an ultraviolet curable resin or a thermosetting resin, can be used.

As an example of the sealing material 51, for example, an ultraviolet curable or thermosetting epoxy resin adhesive may be used. Moreover, the sealing material 51 may be an epoxy resin material having a getter function.

The viscosity of the sealing material 51 is not particularly limited as long as it can be patterned. For example, a material in the range of 100 to 1000 Pa · s is used.

Further, it is preferable that the sealing material 51 has little or no outgas during curing, and a lower shrinkage rate during curing is preferable because it does not damage the organic EL layer 22.

In addition, when the sealing material 51 is a thermosetting type, there is a heat resistance limit of the light emitting layer. preferable.

Further, the moisture permeability of the sealing material 51 is preferably low. Further, in order to adjust the height (gap) of the sealing material 51 between the pair of substrates, it is preferable that a spacer or the like having a desired height is mixed in the sealing material 51.

<Filler 52>
A space between the pair of substrates surrounded by the sealing material 51 is filled with a filler 52 in order to protect the organic EL element 20 from moisture, oxygen, or external impact.

Examples of the filler 52 include resins such as epoxy resins and silicon resins.

Also, in order to improve the moisture adsorption function, the filler 52 may contain a desiccant such as CaO. The filler 52 may or may not have adhesiveness. For example, the filler 52 may be a filled resin layer having adhesiveness containing a desiccant.

The filler 52 may be a material that only needs to be sealed, or may be a curable material. That is, the filler 52 may be a curable filler or a non-curable filler such as liquid or gel. Further, a material that undergoes phase transition by external energy such as heat or ultraviolet light may be used, or a material that does not undergo phase transition may be used. For example, it may be a material that solidifies or vaporizes by heating, may be a material that does not solidify and increases in viscosity, or a material that decreases in viscosity, such as a gel becoming liquid.

However, in the present embodiment, the sealing material 51 and the filler 52 are applied to different substrates of the pair of substrates. For this reason, it goes without saying that a material that can be applied to the substrate, such as liquid or gel, is used as the filler 52.

Further, the curable filler may be an ultraviolet curable filler, a thermosetting filler, or an ultraviolet and heat curable filler.

The viscosity of the sealing material 51 is not particularly limited, and the desired viscosity varies depending on the application method.

For example, when applying the filler 52 by dispenser drawing, the viscosity of the filler 52 is preferably about 0.1 to 1 Pa · s at the time of application. Further, when the filler 52 is applied by a slit coater, it is desirable that the viscosity at the time of application is lower.

In particular, when the filler 52 is applied to the element substrate 30, the viscosity of the filler 52 is preferably in the range of 100 to 1000 Pa · s.

In addition, it applies to the board | substrate using the filler of the viscosity which is easy to apply | coat as the filler 52, and after evaporating a part of solvent contained in the filler 52 to raise the viscosity of the filler, In the case of bonding, the viscosity of the filler 52 at the time of bonding the substrates (for example, after evaporation of the solvent) is not particularly limited as long as it is a viscosity that can be patterned, but is about 10 to 1000 Pa · s. Is desirable, and more desirably within the range of 100 to 1000 Pa · s.

In addition, when the filler 52 is a curable filler, it is preferable that the outgas at the time of curing is small or not like the sealing material 51, and the shrinkage rate at the time of curing is as follows. The lower one is preferable because it does not damage the organic EL layer 22.

Further, when the filler 52 is a thermosetting type, since there is a limit to the heat resistance of the light emitting layer, the filler 52 is preferably curable at 100 ° C. or less, similarly to the seal material 51, at 80 ° C. or less. More preferred is curable.

Further, it is desirable to use a filler having a getter function as the filler 52 because the organic EL element 20 can be more reliably protected from moisture and oxygen. For this reason, the one where the moisture absorption amount of the filler 52 is higher is preferable.

In addition, when the organic EL display panel 1 has a top emission structure, the color of the filler 52 affects the light emission luminance and the light emission color, so that it is preferable that the color is high and the transmittance is high.

<Method for Manufacturing Organic EL Display Panel 1>
Next, the manufacturing method of the organic EL display panel 1 according to the present embodiment will be described below. The manufacturing method of the organic EL display panel 1 according to the present embodiment can be applied to the case where the organic EL display panel 1 is either a top emission type or a bottom emission type. A case where the EL display panel 1 is a top emission type will be described as an example.

1A to 1F are cross-sectional views showing an example of a method for manufacturing the organic EL display panel 1 according to the present embodiment in the order of steps.

First, as shown in FIG. 1A, an organic EL element 20 is formed on a TFT substrate 10 by a known method.

Specifically, as shown in FIG. 1A, a TFT 12 and a signal line 13 such as a gate line and a source line are formed on a base substrate 11 made of, for example, a glass substrate by a known method. An interlayer insulating film 14 provided with contact holes 14a is formed thereon by a known method so as to cover these TFTs 12 and signal lines 13.

The interlayer insulating film 14 and the contact hole 14a are formed by applying a photosensitive resin such as an acrylic resin or a polyimide resin on the base substrate 11 on which the TFT 12 and the signal line 13 are formed, and patterning by a photolithography technique. It is formed.

Subsequently, the first electrode 21 and the edge cover 15 are formed on the interlayer insulating film 14.

1st electrode 21 can be formed by laminating | stacking the transparent electrode material which has electroconductivity and permeability | transmittance, such as ITO, using a sputtering method etc., for example.

Thereafter, the edge cover 15 is fabricated so as to cover the end portion (pattern end portion) of the first electrode 21 on the interlayer insulating film 14 and to form the opening portion 15 a for each pixel 2. Similar to the interlayer insulating film 14, a known photosensitive resin such as an acrylic resin or a polyimide resin can be used for the edge cover 15.

Through the above steps, the TFT substrate 10 on which the first electrode 21 and the edge cover 15 are formed is manufactured.

Next, the organic EL layer 22 and the second electrode 23 that form the light emitting portion of the organic EL display panel 1 together with the first electrode 21 are sequentially formed on the TFT substrate. As described above, the organic EL layer 22 may be a single layer type or a multilayer type. This organic EL layer 22 can be formed by, for example, vacuum deposition. The second electrode 23 is formed, for example, by vacuum deposition of a metal such as Al having conductivity.

Thereby, the organic EL element 20 including the first electrode 21, the organic EL layer 22, and the second electrode 23 is formed on the TFT substrate 10.

Thereafter, as shown in FIG. 1B, a sealing film 31 is formed so as to cover the organic EL element 20 across the light emitting region 3 and the non-light emitting region 4 of the organic EL element 20.

Note that, as described above, the sealing film 31 may have a single layer or a laminated structure of an inorganic film, or may have a laminated structure of an inorganic film and an organic film.

The inorganic film can be formed by, for example, the above-described inorganic material by plasma CVD, thermal CVD, vacuum deposition, sputtering, or the like.

Further, the organic film can be formed, for example, by vacuum deposition of the above-described organic material.

In any case, there is a technique that does not significantly increase the temperature of the element substrate 30 on which the organic EL layer 22 is formed, preferably a technique that can maintain the element substrate 30 at 100 ° C. or lower. Used.

Through the above process, the element substrate 30 used in the present embodiment is manufactured.

Next, as shown in FIG. 1C, a sealing material 51 is applied to the element substrate 30. When the sealing film 31 is provided on the element substrate 30, the sealing material 51 is applied on the sealing film 31, for example, in a frame shape so as to surround the organic EL element 20.

Examples of the method for applying the sealing material 51 include drawing with a dispenser or screen printing. The type and viscosity of the sealing material 51 are as described above, and the description thereof is omitted here.

On the other hand, as shown in FIG. 1D, a filler 52 is applied to the counter substrate 40. The configuration of the counter substrate 40 is as described above. Here, for example, a sealing glass made of a glass substrate is used as the counter substrate 40. The filler 52 is applied on the sealing glass.

Examples of the method for applying the filler 52 include drawing with a dispenser, screen printing, ink jet printing, and application with a slit coater. The type and viscosity of the filler 52 are as described above, and the description thereof is omitted here. As the filler 52, for example, a filler having a desiccant function is used.

In addition, after applying the filler 52 to the counter substrate 40, the counter substrate 40 may be heated (for example, baked) with an oven or a hot plate, for example, in order to remove a part of the solvent contained in the filler 52. Good. Of course, when the solvent contained in the filler 52 is a volatile component, it is not always necessary to heat, and after the filler 52 is applied to the counter substrate 40, it may be left until the volatile component is volatilized to some extent. Absent.

Thereafter, as shown in FIG. 1E, the element substrate 30 coated with the sealing material 51 and the counter substrate 40 coated with the filler 52 are bonded together by a vacuum bonding apparatus (not shown). Seal. In the vacuum bonding apparatus, after the pair of substrates are bonded together in a vacuum, the pressure is returned to atmospheric pressure, and the sealing material 51 is cured by heat or ultraviolet rays (UV).

Thereby, the organic EL display panel 1 shown in FIG. 1F and FIG. 2 in which the element substrate 30 and the counter substrate 40 are bonded together with the sealing material 51 is manufactured.

It should be noted that the thickness and size of each component in each substrate described above may be appropriately set to a desired thickness and size according to the application and the like, and are not particularly limited. The thickness and size of these components can be set, for example, in the same manner as in the past.

The counter substrate 40 may have the same size as the element substrate 30, or after using a larger substrate than the element substrate and sealing the organic EL element 20 between the pair of substrates. Further, it may be divided according to the size of the target organic EL display panel 1.

<Effect>
As shown in FIGS. 6A and 6B, when the sealing material 51 and the filling material 52 are applied to the same substrate, the sealing material 51 is formed even if the filling material 52 is not in contact with the sealing material 51. Under the influence of the solvent atmosphere of the filler 52, seal insertion and seal breakage occur when a pair of substrates are bonded together.

However, according to the present embodiment, as described above, the sealing material 51 and the filler 52 are applied to different substrates of the pair of substrates until the sealing material 51 is cured. The time during which the filler 52 is in contact with or close to the sealing material 51 can be shortened. For this reason, such seal insertion and seal breakage can be prevented.

Further, according to the present embodiment, as described above, a part of the solvent contained in the filler 52 is applied by applying the sealing material 51 to the element substrate 30 and applying the filler 52 to the counter substrate 40. After removing the substrate, the pair of substrates can be sealed.

Thus, by removing a part of the solvent contained in the filler 52, the viscosity of the filler 52 can be made higher than when the filler 52 is applied.

For this reason, even if there is a pinhole or foreign matter in the sealing film 31, the penetration speed of the filler 52 into the sealing film 31 can be reduced. Therefore, for example, even when the filler 52 is curable and the solvent contained in the filler 52 causes a large damage to the organic EL element 20, before the organic EL element 20 is damaged, The filler 52 can be cured by bonding the pair of substrates. Thereby, deterioration of the organic EL element 20 can be prevented.

Further, when a curable filler is used as the filler 52 in this way, a low-viscosity material that can be easily applied can be used as the filler 52 by applying the filler 52 to the counter substrate 40. Even when such a low-viscosity material is used as the filler 52, the pair of substrates is bonded to each other by evaporating the solvent to some extent by baking the counter substrate 40 after applying the filler. After that, it is possible to prevent the solvent from penetrating into the organic EL element 20 until the filler 52 is cured.

In addition, when the filler 52 contains a volatile component that causes deterioration of the organic EL element 20, or outgas that causes deterioration of the organic EL element 20 due to heating or the like when the pair of substrates is bonded to each other. When generated, the volatile component as described above is obtained by removing a part of the solvent contained in the filler 52 by, for example, heating or leaving in advance after applying the filler 52 to the counter substrate 40 as described above. After the outgas is removed, the pair of substrates can be attached.

Therefore, regardless of whether the filler 52 is a curable type or a non-curable type, even a filler containing a solvent that generates such a volatile component or outgas can be used. Can be used, for example, by adding to the filler in order to lower the viscosity during coating.

In addition, when the filler 52 is applied to the element substrate 30, in order to prevent the organic EL element 20 from deteriorating, it is usually impossible to apply a temperature of 80 ° C. or higher. However, when the filler 52 is applied to the counter substrate 40 as in the present embodiment, there is no such limitation. For this reason, even if it is a solvent with a high boiling point, it can be evaporated. Therefore, even if the filler 52 contains such a solvent, such a solvent can be removed. Therefore, it is possible to efficiently and sufficiently remove the solvent / volatile component that causes the deterioration of the organic EL element 20. For this reason, deterioration of the organic EL element 20 can be suppressed.

Thus, the solvent removal process of evaporating a part of the solvent contained in the filler 52 (that is, the filler 52 applied to the counter substrate 40) between the application process of the filler 52 and the substrate bonding process. After removing the solvent that degrades the organic EL element 20 contained in the filler 52, or after increasing the viscosity of the filler 52 than when applying the filler 52, the sealing is performed. Since it can be performed, deterioration of the organic EL element 20 can be prevented, and seal insertion and seal failure can be prevented.

In addition, when a part of the solvent contained in the filler 52 is evaporated as described above, the filler 52 may contain only one type of solvent, but contains two or more types of solvents having different boiling points. May be.

When the filler 52 includes two or more kinds of solvents having different boiling points (for example, when the filler 52 is constituted of two or more kinds of solvents having a composition ratio of 5% by weight or more), the filler After coating 52 on the counter substrate 40, the counter substrate 40 is heated to a temperature not lower than the boiling point of the first solvent and lower than the boiling point of the second solvent among the solvents contained in the filler 52, thereby filling the filler. After removing the first solvent from 52, the counter substrate 40 and the element substrate 30 can be bonded together.

Thus, after applying the filler 52 to the counter substrate 40 with a viscosity that is easy to apply, the pair of substrates can be bonded together in a state where the filler 52 is maintained at a certain viscosity (desired viscosity). it can. Thereby, mixing of bubbles between the pair of substrates can be prevented, and the gap between the pair of substrates can be filled with the filler 52.

Moreover, when the 1st solvent contains the component which degrades the organic EL element 20, the 1st solvent which degrades the organic EL element 20 can be removed completely before bonding a pair of said board | substrate. It becomes. Therefore, when the filler 52 contains a solvent that degrades the organic EL element 20 as the first solvent, it is preferable to use the filler 52 mixed with a second solvent having a boiling point higher than that of the first solvent. .

Further, according to the present embodiment, it is possible to improve the tact time by applying the sealing material 51 and the filler 52 to different substrates as described above.

As described above, when a heating process is used to evaporate a part of the solvent after applying the filler 52, it is also possible to prepare a substrate on which the filler 52 has been previously applied. This process is particularly effective in the case of using a material that will cause a seal insertion / cut if the substrates are not bonded immediately after application.

[Embodiment 2]
This embodiment will be described mainly with reference to FIG.

In the present embodiment, differences from the first embodiment will be mainly described. Components having the same functions as those used in the first embodiment are denoted by the same reference numerals. The description is omitted.

FIG. 3 is a cross-sectional view showing a substrate bonding step in the method of manufacturing the organic EL display panel 1 according to the present embodiment. FIG. 3 shows the same step as the step shown in FIG.

As shown in FIG. 1E, in the first embodiment, the sealing material 51 is applied to the element substrate 30 and the filling material 52 is applied to the counter substrate 40. On the other hand, the present embodiment is different from the first embodiment in that the filler 52 is applied to the element substrate 30 and the sealing material 51 is applied to the counter substrate 40 as shown in FIG.

In the present embodiment, the configuration of the organic EL display panel 1 finally obtained is the same as that of the first embodiment.

In the case where the organic EL element 20 is not damaged even if the filler 52 soaks into the organic EL element 20, the filler 52 may be applied to the element substrate 30 as shown in FIG. However, also in this embodiment, when the sealant 51 and the filler 52 are applied to the same substrate, even when the filler 52 is not in contact with the sealant 51, when the pair of substrates is bonded, Seal insertion or seal breakage occurs. For this reason, as shown in FIG. 3, when the filler 52 is applied to the element substrate 30, the sealing material 51 must be applied to the counter substrate 40.

<Effect>
Also in this embodiment, as described above, the sealant 51 and the filler 52 are applied to different substrates of the pair of substrates, so that the filler 52 is cured until the sealant 51 is cured. The time during which the sealing material 51 is in contact with or close to the sealing material 51 can be shortened. For this reason, seal insertion and seal breakage can be prevented.

Further, according to the present embodiment, the unevenness of the element formation surface (active surface) in the element substrate 30 is filled by applying the sealing material 51 to the counter substrate 40 and applying the filler 52 to the element substrate 30. The material 52 can be easily filled with no gap.

Further, when the sealing material 51 and the filler 52 are applied on the same substrate as in the prior art, if a high-viscosity filler is used as the filler 52, the filler 52 is applied or the pair of substrates is At the time of bonding, there is a problem that the sealing material 51 is broken by the high-viscosity filler 52 and the sealing property cannot be maintained. In addition, there is a limit from the viewpoint of the coating apparatus to increase the viscosity of the sealing material 51 so that the sealing material 51 is not broken by the high-viscosity filler 52.

However, according to the present embodiment, by applying the sealing material 51 to the counter substrate 40 as described above, the counter substrate 40 to which the sealing material 51 is applied is heated before the substrate bonding step. Thus, a part of the solvent of the sealing material 51 can be removed.

For this reason, according to the present embodiment, after the sealing material 51 is applied and before the substrate bonding step, the sealing material 51 is made higher in viscosity than the viscosity of the filler 52 in advance, and then the pair of substrates. Can be pasted together. For this reason, even when a highly viscous filler is used as the filler 52, the unevenness of the surface of the element substrate 30 due to the organic EL element 20 can be filled without a gap. For this reason, air bubbles can be prevented from being mixed between the pair of substrates.

Further, since the sealing can be performed even when the high-viscosity filler 52 is used, a filler with less outgas can be used as the filler 52, so that the reliability can be improved.

Further, by using the high-viscosity filler 52 in this way, it is possible to suppress element deterioration due to seal insertion, seal breakage, and penetration of the solvent in the filler 52.

[Embodiment 3]
The following will describe the present embodiment mainly based on FIGS. 4A and 4B and FIGS. 5A and 5B.

In this embodiment, differences from

Embodiments

1 and 2 will be mainly described, and the same components as those used in

Embodiments

1 and 2 have the same functions. A number is assigned and description thereof is omitted.

As described in the first and second embodiments, regarding the filler 52, whether or not the organic EL element 20 is damaged selects which of the pair of substrates the filler 52 is applied to. Used as a selective material for.

However, when the wiring in the element substrate 30 has a forward taper shape that becomes thinner from the lower part to the upper part of the element substrate 30, the sealing material 51 is applied to the element substrate 30 side as shown in the first embodiment. Alternatively, it may be applied to the counter substrate 40 side as shown in the second embodiment. For this reason, when the wiring in the element substrate 30 has a forward taper shape, the sealing material 51 is a substrate on which the filler 52 is applied depending on which of the pair of substrates the filler 52 is applied. What is necessary is just to apply | coat to the board | substrate of a different side.

Here, the upper part of the element substrate 30 indicates the surface side of the element substrate 30 (that is, the element formation surface side). Therefore, the direction from the lower part to the upper part of the element substrate 30 indicates the direction from the element substrate 30 side to the counter substrate 40 side.

However, depending on the shape of the wiring in the element substrate 30 (more strictly, the shape of the wiring in the seal portion by the sealing material 51), when the sealing material 51 is applied to the counter substrate 40 side, the pair of substrates are bonded together. In addition, there may be a gap between the sealing material 51 and the wiring.

FIGS. 4A and 4B are diagrams schematically showing a cross section of the seal portion before and after the substrates are bonded together when the sealing material 51 is applied to the element substrate 30 side when the wiring is reversely tapered. It is. 5A and 5B schematically show a cross section of the seal portion before and after the substrates are bonded together when the sealing material 51 is applied to the counter substrate 40 side when the wiring is reversely tapered. FIG. 4A and 5A show the state before the substrates are bonded together, and FIG. 4B and FIG. 5B show the state after the substrates are bonded together.

As shown in FIG. 5A, the terminal wiring 16 (for example, TFT terminal wiring) that is the wiring in the seal portion is opposed when it has an inversely tapered shape that becomes thicker from the lower part to the upper part of the element substrate 30. When the sealing material 51 is applied to the substrate 40, the sealing material 51 is cured without the sealing material 51 entering the reverse tapered portion of the terminal wiring 16 when the substrates are bonded. This is because the sealing material 51 does not easily spread in the reverse taper portion of the terminal wiring 16, and the reverse taper portion is difficult to be filled with the sealing material 51.

For this reason, when the sealing material 51 is applied to the counter substrate 40 when the terminal wiring 16 has a reverse taper shape as described above, as shown in FIG. A gap 101 is generated.

Further, when a spacer or the like (not shown) is mixed in the sealing material 51 in order to adjust the height of the sealing material 51 between the pair of substrates (that is, the gap between the substrates), the spacer is connected to the terminal wiring 16. This hinders the spread of the sealing material 51 to the reverse taper portion, and further increases the possibility of the gap 101 as described above.

For this reason, when the wiring in the seal portion is reversely tapered as described above, it is desirable to apply the sealing material 51 on the element substrate 30 side and bond the pair of substrates together as shown in FIG. .

<Effect>
According to the present embodiment, even when the terminal wiring 16 is reversely tapered as shown in FIG. 4A, the wetting and spreading of the sealing material 51 is improved, as shown in FIG. 4B. , The gap in the seal portion can be eliminated (or the possibility of forming a gap is reduced).

[Modification]
In the first to third embodiments, as an example of a method for manufacturing a bonded substrate, a method for manufacturing an organic EL display panel 1 using an organic EL element substrate including an organic EL element as the element substrate 30 is taken as an example. Explained.

However, it is needless to say that the organic EL element and the inorganic EL element are different in material, and the bonded substrate may be an inorganic EL display panel. That is, the method for manufacturing a bonded substrate according to Embodiments 1 to 3 is similarly applied to the manufacture of an inorganic EL display panel using an inorganic EL device substrate including an inorganic EL device instead of the organic EL device substrate. Is possible.

In addition, as described above, when the pair of substrates are bonded to each other through the sealing material 51 and the filler 52, the manufacturing method of the bonded substrate is used to attach the sealing material 51 and the filler 52 to the pair of substrates. Of these, they are applied to different substrates. Therefore, the manufacturing method of the above-mentioned bonded substrate is not limited to the EL display panel, and is filled between an element substrate (for example, an element substrate such as a TFT substrate) having a driving element such as a TFT as an element and a counter substrate. The same applies to a liquid crystal display panel filled with liquid crystal as a material.

The configuration of the liquid crystal display panel is conventionally known, and the description and illustration thereof are omitted here.

[Summary]
The manufacturing method of the bonding substrate concerning the aspect 1 of this invention is a manufacturing method of the bonding substrate which bonds an element substrate and a counter substrate through a sealing material and a filler as mentioned above, Comprising: The said sealing material And the filler are applied to different substrates of the element substrate and the counter substrate.

When the sealant and filler are applied to the same substrate, the sealant is affected by the solvent atmosphere of the filler even if the filler is not in contact with the sealant, and seals when a pair of substrates are bonded together Insertion or seal breakage occurs.

However, according to the above method, the sealing material and the filler are applied to different substrates of the pair of substrates, so that the filler contacts or approaches the sealing material until the sealing material is cured. You can shorten your time. For this reason, such seal insertion and seal breakage can be prevented.

Especially, in order to prevent deterioration of the element, the element substrate cannot be heated to a very high temperature. For example, when the element substrate is an organic EL (electroluminescence) substrate, a temperature of 80 ° C. or higher cannot be applied to the element substrate in order to prevent deterioration of the organic EL element.

However, there is no such limitation on the counter substrate, and even a solvent having a high boiling point can be evaporated. That is, by applying the sealing material and the filler to different substrates of the pair of substrates, the material applied to the counter substrate side can be heated to a temperature equal to or higher than the heat resistance temperature of the element.

For this reason, for example, even when the filler contains a solvent that causes deterioration of the element provided on the element substrate, such as an organic EL element, before the pair of substrates are bonded together, It is possible to remove an unnecessary solvent and to suppress / prevent deterioration of the element.

For this reason, according to the above method, when the element substrate and the counter substrate are bonded to each other through the sealant and the filler, it is possible to suppress seal insertion and seal breakage and to suppress element deterioration.

Also, according to the above method, tact-up can be achieved by applying the sealing material and the filler to different substrates.

In the method for manufacturing a bonded substrate according to aspect 2 of the present invention, in the aspect 1, it is preferable that the sealing material is applied to the element substrate and the filler is applied to the counter substrate.

Moreover, the manufacturing method of the bonding board | substrate concerning the aspect 3 of this invention is the said filling in the said aspect 2, after apply | coating the said filler to the said opposing substrate, before bonding the said element substrate and the said opposing substrate. It is preferable to include a solvent removal step of evaporating a part of the solvent contained in the material so that the viscosity of the filler becomes higher than that during the application of the filler.

In the method for manufacturing the bonded substrate, in particular, by applying the sealing material to the element substrate and applying the filler to the counter substrate, for example, after applying the filler to the counter substrate, Before the element substrate and the counter substrate are bonded to each other, a part of the solvent contained in the filler can be evaporated.

Further, according to the above method, by evaporating a part of the solvent contained in the filler, the viscosity of the filler can be made higher than that at the time of applying the filler.

Thus, by making the viscosity of the filler higher than that at the time of application of the filler, even if there is a pinhole or a foreign object in a film such as a protective film covering the element, the filler in the element The penetration speed can be reduced. For this reason, for example, even when the filler is curable and the solvent contained in the filler gives a large damage to the element, the pair of substrates is bonded before the element is damaged. And the filler can be cured. Thereby, deterioration of an element can be prevented.

Also, as described above, when the filler is applied to the counter substrate side, a low-viscosity material that can be easily applied can be used as the filler. Even when such a low-viscosity material is used as the filler, a part of the solvent can be evaporated by heating the counter substrate after applying the filler.

Even when the filler contains a solvent that causes deterioration of the element or when outgas that causes deterioration of the element due to heating or the like is generated, the filler is applied to the counter substrate side. As described above, the pair of substrates can be bonded together after removing such a solvent or outgas by volatilization or heating.

Therefore, in the method for manufacturing the bonded substrate, it is preferable to apply the sealing material to the element substrate and apply the filler to the counter substrate. In this case, the filler is applied to the counter substrate. Thereafter, before the element substrate and the counter substrate are bonded to each other, a part of the solvent contained in the filler is evaporated to remove the solvent so that the viscosity of the filler is higher than that during the application of the filler. More preferably, the method includes a step.

The method for manufacturing a bonded substrate according to Aspect 4 of the present invention is the above-mentioned Aspect 3 (that is, when the method for manufacturing a bonded substrate includes the solvent removal step as described above), the filler has a boiling point. In the solvent removal step, the counter substrate is heated to a temperature equal to or higher than the boiling point of the first solvent and lower than the boiling point of the second solvent. It is more preferable to remove the first solvent.

According to the above method, after the filler is applied to the counter substrate, the pair of substrates can be bonded together after removing the first solvent from the filler.

Thus, after the filler is applied to the counter substrate with a viscosity that is easy to apply, the pair of substrates can be bonded together while the filler is maintained at a desired viscosity. Thereby, mixing of bubbles between the pair of substrates can be prevented, and the gap between the pair of substrates can be filled with the sealing material.

In the method for manufacturing a bonded substrate according to aspect 5 of the present invention, in the aspect 4, the first solvent may be a solvent that degrades the element.

As described above, when the first solvent is a solvent that deteriorates the device, a more remarkable effect can be obtained.

That is, in the case where the first solvent is a solvent that degrades the element, the solvent can be completely removed before the pair of substrates are bonded to each other.

In the bonded substrate manufacturing method according to Aspect 6 of the present invention, in any one of Aspects 2 to 5, the wiring of the seal portion in the element substrate becomes thicker from the lower part to the upper part of the element substrate. In the case of a reverse taper shape (in other words, in the case of a reverse taper shape that becomes thicker from the element substrate side toward the counter substrate side), as described above, the sealing material is applied to the element substrate, and It is desirable to apply a filler to the counter substrate.

When the wiring has a reverse taper shape, if a sealing material is applied to the counter substrate, the sealing material does not enter the reverse taper portion of the wiring, and a gap is generated in the reverse taper portion of the wiring.

However, the gap in the seal portion can be eliminated by applying the seal material to the element substrate.

The method for manufacturing a bonded substrate according to aspect 7 of the present invention may be a method of applying the filler to the element substrate and applying the sealing material to the counter substrate in the aspect 1.

In the method for manufacturing the bonded substrate, the unevenness of the element formation surface (active surface) in the element substrate is formed by applying the filler to the element substrate and applying the sealing material to the counter substrate. Can be filled easily without gaps.

In this case, a part of the solvent contained in the sealing material applied to the counter substrate can be evaporated.

The method for manufacturing a bonded substrate according to Aspect 8 of the present invention is the method for manufacturing a bonded substrate according to Aspect 7, wherein the sealing material is applied to the counter substrate and then bonded to the counter substrate before the element substrate and the counter substrate are bonded to each other. It is preferable to include a solvent removing step of evaporating a part of the contained solvent to make the viscosity of the sealing material higher than that of the filler.

∙ By using a high-viscosity filler as the filler, it is possible to suppress element deterioration due to seal insertion, seal breakage, and penetration of the solvent of the filler.

However, in the past, since the sealing material and the filler were applied on the same substrate, the sealing material was broken by the high-viscosity filler, and the sealing performance could not be maintained. It has been difficult to use a high-viscosity filler because there is a limit to increasing the viscosity of the sealing material so that the sealing material is not broken by the viscous filler.

However, according to the above method, by applying the filler to the element substrate and applying the sealing material to the counter substrate, the counter material to which the sealing material is applied before the substrate bonding step is applied. A part of the solvent of the sealing material can be removed by heating the substrate.

For this reason, according to said method, after apply | coating a sealing material and before a board | substrate bonding process, after making a sealing material into viscosity higher than the viscosity of a filler previously, bonding a pair of said board | substrate. Can do. For this reason, even when a high-viscosity filler is used as the filler, the irregularities on the surface of the element substrate can be filled without gaps, and air bubbles are prevented from being mixed between the pair of substrates. Can do.

Further, since the above method can seal even when a highly viscous filler is used, a filler with less outgas can be used as the filler. For this reason, the reliability of the bonding substrate can be improved.

Further, in the method for producing a bonded substrate according to the ninth aspect of the present invention, in any one of the first to eighth aspects, the filler is preferably a curable filler.

According to the above method, it is possible to shorten the time during which the filler or the solvent contained in the filler contacts the element before the filler is cured. In addition, the filler may contain a solvent that causes deterioration of the element. For this reason, the above method is particularly suitable when the filler is a curable filler.

In addition, in the method for manufacturing a bonded substrate according to aspect 10 of the present invention, in any one of the above aspects 1 to 9, the element substrate is preferably an organic EL (electroluminescence) element substrate.

Organic EL elements are vulnerable to moisture, oxygen, etc., and must be protected from external impacts, etc. Filled between the element substrate and the counter substrate to enhance protection and maintain a gap between substrates. It is preferable that the material is enclosed.

Also, in order to prevent the deterioration of the organic EL element, a temperature of 80 ° C. or higher cannot be applied to the element substrate.

For this reason, the manufacturing method of the said bonded substrate is especially suitable when the element substrate is an organic EL element substrate. In other words, the manufacturing method of the said bonding board | substrate can be used especially suitably for the manufacturing method of the organic EL display panel which used the organic EL element substrate as an element substrate.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

The present invention can be suitably used in a method for producing a bonded substrate such as an organic EL display panel, an inorganic EL display panel, and a liquid crystal display panel.

1 Organic EL display panel (bonding substrate)
2 pixel 3 light emitting area 4 non-light emitting area 10 TFT substrate 11 base substrate 12 TFT
13 signal line 13a contact hole 14 interlayer insulating film 14a contact hole 15 edge cover 15a opening 16 terminal wiring 20 organic EL element (element)
21 First electrode 22 Organic EL layer 23 Second electrode 30 Element substrate 31 Sealing film 40 Counter substrate 51 Sealing material 52 Filling material 101 Crevice 111 Pinhole

Claims

A method for manufacturing a bonded substrate in which an element substrate and a counter substrate are bonded together via a sealant and a filler, wherein the sealant and the filler are applied to different substrates of the element substrate and the counter substrate. The manufacturing method of the bonding board | substrate characterized by the above-mentioned.
The method for producing a bonded substrate according to claim 1, wherein the sealing material is applied to the element substrate, and the filler is applied to the counter substrate.
After the filler is applied to the counter substrate, before the element substrate and the counter substrate are bonded together, a part of the solvent contained in the filler is evaporated to reduce the viscosity of the filler. The method for producing a bonded substrate according to claim 2, further comprising a solvent removal step of increasing the viscosity as compared with the time of application.
The filler includes two or more solvents having different boiling points,
In the solvent removal step, the counter substrate is removed by heating the counter substrate to a temperature not lower than the boiling point of the first solvent and lower than the boiling point of the second solvent among the solvents contained in the filler. The manufacturing method of the bonding board | substrate of Claim 3 characterized by these.
The method for producing a bonded substrate according to claim 4, wherein the first solvent is a solvent that deteriorates the element.
The bonding substrate according to any one of claims 2 to 5, wherein the wiring of the seal portion in the element substrate has an inversely tapered shape that increases in thickness from the lower part to the upper part of the element substrate. Production method.
The method for producing a bonded substrate according to claim 1, wherein the filler is applied to the element substrate, and the sealing material is applied to the counter substrate.
After the sealing material is applied to the counter substrate, before the element substrate and the counter substrate are bonded to each other, a part of the solvent contained in the sealing material is evaporated to obtain the viscosity of the sealing material. The manufacturing method of the bonding board | substrate of Claim 7 characterized by including the solvent removal process which makes it more viscous than this.
The method for producing a bonded substrate according to any one of claims 1 to 8, wherein the filler is a curable filler.
The method for producing a bonded substrate according to any one of claims 1 to 9, wherein the element substrate is an organic electroluminescence element substrate.