JP2001343516A - Method for manufacturing transfer substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a transfer substrate having a release layer such that the release layer does not peel in the succeeding processes after the release layer is formed. SOLUTION: The method includes a process of applying a coating type insulating film on an insulating substrate to cover the side faces of the insulating substrate, a process of decreasing the film thickness of the coating film formed on the side face of the insulating substrate, a process of heating and hardening the coating film to form a release film layer, a process of forming a transparent conductive layer on the release layer and a process of forming an adhesive layer on the transparent conductive layer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a transfer substrate for manufacturing a substrate having a color filter, a transparent electrode and the like used for a color liquid crystal panel or the like by utilizing transfer.

[0002]

2. Description of the Related Art In recent years, low power consumption, low voltage operation, light weight,
Liquid crystal panels characterized by thinness, color display, and the like are rapidly expanding their applications to personal computers (PCs) and video equipment. Generally, the liquid crystal panel is 2
It has a structure in which liquid crystal is sealed between two transparent substrates.
A transparent electrode, a color filter, an alignment film and the like are formed on one of two surfaces of the transparent substrate facing each other, and a TFT (thin film transistor) is formed on the other surface.
Alternatively, a stripe-shaped transparent electrode and an alignment film are formed. Hereinafter, a substrate on which a transparent electrode, a color filter, and the like are formed is referred to as a CF substrate.

In this CF substrate, for example, red (R), green (G), and blue (B) pixels are arranged on a transparent substrate made of glass, and a black layer is formed between these pixels. Above these, a transparent electrode is formed. These are generally formed directly on a glass substrate using methods such as photolithography, printing, and electrodeposition. This glass substrate is excellent in terms of surface smoothness, light transmittance, and other characteristics relating to display, but the glass substrate has a problem that when the thickness is reduced, the glass substrate is easily broken and the weight is heavy. Therefore, there is a problem when a glass substrate is used as a CF substrate of a portable liquid crystal panel where importance is placed on durability and miniaturization.

In order to solve such problems of the glass substrate, a method of forming a color filter layer and a transparent electrode on a transparent substrate made of plastic or the like has been proposed.
However, this plastic substrate, compared to the glass substrate,
Poor in chemical resistance, heat resistance and expansion and contraction due to temperature and humidity.
That is, when temperature and humidity are added to the plastic substrate,
Due to the dimensional change, it is difficult to directly form a high-precision color filter pattern on a plastic substrate by using a photolithography method or the like. In addition, since a plastic substrate does not have high heat resistance, it is difficult to perform a high-temperature treatment for forming a low-resistance film such as a transparent electrode.

Therefore, in a state where it can be peeled off on a temporary substrate,
By forming a release layer, a transparent electrode, a color filter layer, an adhesive layer, and the like, and transferring these from a temporary substrate to a transparent substrate made of plastic or the like via an adhesive layer, the transparent electrode or the like is formed on a plastic substrate. A method for forming a color filter layer and the like has been proposed.

[0006]

In the above method, since the release layer is peeled off from the temporary substrate and the transparent electrode and the color filter layer are transferred onto the plastic substrate, the adhesion between the temporary substrate and the release layer is reduced. Sex should be relatively low. However, since a pattern such as a transparent electrode or a color filter layer is formed on the release layer, the provisional substrate and the release layer form a photolithography step, an etching step, It is necessary to have a certain degree of adhesion that can withstand a washing step or the like.

That is, since the peeling layer which can be easily peeled off from the temporary substrate has low adhesion to the substrate, it can be used in a subsequent step, for example, a chemical treatment in a transparent electrode pattern forming step or a color filter layer forming step. Peeling may occur in a so-called wet process such as a process or a cleaning process. An object of the present invention is to provide a method of manufacturing a transfer substrate having a release layer that does not cause peeling of a release layer in a step after a step of forming a release layer and that can be easily peeled off from a temporary substrate. It is.

[0008]

Means for Solving the Problems The object of the present invention is to apply a coatable insulating film on an insulating substrate so as to cover the side surface of the insulating substrate, and to form a coating film. A step of reducing the thickness of the coating film formed on the side surface; a step of heating and curing the coating film to form a release layer; and a step of forming a transparent conductive layer on the release layer. Forming an adhesive layer on the transparent conductive layer.

In general, when a coating film is formed on the surface and side surface of a substrate by spin coating, the thickness of the coating film formed on the peripheral portion and side surface of the substrate is larger than the film thickness at the central portion of the substrate. Then, a step is generated in the peripheral portion of the substrate. For this reason, the coating film formed on the peripheral portion and the side surface of the substrate is removed by spraying an organic solvent or the like on the peripheral portion and the side surface of the substrate, that is, by performing so-called edge cleaning.

However, when this method is used, the coating film on the peripheral portion of the substrate is removed, so that the coating film is formed by a wet process such as a developing process of a photolithography process for forming another pattern on the coating film. The chemical liquid permeates from the interface between the film and the substrate, and the coating film easily peels off from this interface. According to the present invention, there is provided a step of forming a release layer which is an insulating coating film so as to cover a side surface of the insulating substrate. According to this, there is no region where the release layer is removed on the surface and the side surface of the insulating substrate, and the entire surface and the side surface of the insulating substrate are covered with the release layer. That is, in the case of performing a chemical treatment such as a developer in the step of forming a transparent conductive layer on the release layer, there is no interface between the insulating substrate and the release layer where the chemical such as the developer easily penetrates. Can be prevented.

In general, when a relatively thick coating film is formed on a substrate by spin coating, the peripheral portion and the side portion of the substrate are formed to be thicker. The thick coating film formed on the side surface of the substrate is likely to come into contact with a member of a transport system in the manufacturing apparatus in a later step and become a source of particles. On the other hand, when the coating film formed on the side surface of the substrate is too thick, the adhesion to the side surface of the substrate is reduced, and the release layer is easily peeled off from the side surface of the substrate.

According to the present invention, there is further provided a step of reducing the thickness of the release layer which is an insulating coating film formed on the side surface of the insulating substrate. According to this, even if the thickness of the release layer on the side surface of the insulating substrate is increased, the thickness is reduced to such an extent that the side surface of the insulating substrate is not exposed, that is, the interface between the release layer and the insulating substrate does not appear. can do. Therefore, even if the release layer on the side surface of the insulating substrate comes into contact with a member of a transport system in the manufacturing apparatus in a later step, a large amount of particles are not generated.

Further, when the thickness of the release layer on the side surface of the insulating substrate is physically reduced, the coating film is formed while being pressed in the side direction of the substrate. Adhesion can be improved. Thereby, the peeling of the release layer can be completely prevented, so that the production yield of the transfer substrate can be improved.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are sectional views showing a method of manufacturing a transfer substrate according to an embodiment of the present invention in the order of steps. First, a glass substrate 10 coated with silica or not coated with silica is used as an insulating substrate.
And pyrometic anhydride and 4,4′-diaminodiphenyl ether as a coating material for a coating insulating film, and a silane coupling agent KBM is added to the resulting polyimide precursor varnish (dimethylacetamide solution, solid content ratio 10%). -573 (Shin-Etsu Silicon Co., Ltd.) 0.05wt
% (Solid content ratio) is prepared. Glass substrate 1
For 0, for example, a square having a side of 300 mm to 1000 mm can be used.

Thereafter, as shown in FIG. 1A, the number of revolutions and the time of the spin coater were adjusted using a spin coater to apply the above-mentioned coating material on the glass substrate 10 so that the film thickness became, for example, 3 μm. The coating film 12 is formed under the conditions. At this time, since the coating film 12 is formed by a spin coater,
The film thickness of the coating film 12 at the peripheral portion of the glass substrate 10 is about 1.5 to 2 times larger than the film thickness at the central portion, and is formed so as to cover the side surfaces.

Next, as shown in FIG. 1B, the thickness of the coating film 12 formed on the side surface of the glass
The coating film 1 on the side surface of the glass substrate 10 is set to about μm.
Etching or scraping only 2 to remove the glass substrate 1
The thickness of the coating film 12 on the 0 side is reduced to form a coating film 12a. Here, a side surface processing apparatus and a processing method of the glass substrate 10 used in this step will be described. FIG. 3A is a schematic perspective view of an apparatus for processing the side surface of the glass substrate 10, and FIG.
2B is a cross-sectional view of the side surface processing apparatus for the glass substrate 10 on which the glass substrate 10 is mounted.

As shown in FIGS. 3A and 3B, the side surface processing device 34 for the glass substrate 10 is movable back and forth.
And a rotatable support table 30 on which the rectangular glass substrate 10 is placed; and a Teflon (registered trademark) or the like, which is disposed on the left and right sides of the support table 30, is movable back and forth, left and right, is rotatable, and is rotatable. It has two pins 32a and 32b. The pins 32a and 32b are connected to the square glass substrate 1
By moving along the side surface of the glass substrate 10 while rotating while contacting the two opposing side surfaces of the glass substrate 10, the coating film 12 on the side surface of the glass substrate 10 can be thinned. Further, by rotating the glass substrate 10 by 90 ° and treating the side surface of the glass substrate 10 in the same manner as described above, the coating film 12 on the other two opposite side surfaces of the glass substrate 10 is processed.
Can be made thinner. Thus, the thickness of the coating film 12 on the four side surfaces of the glass substrate 10 can be reduced.

Next, a method for processing the side surface of the glass substrate 10 using the side surface processing apparatus 34 will be described. First, the glass substrate 10 is transported to the support 30 and the glass substrate 10 is fixed to the support with a vacuum chuck. Then, two pins 32
The positions of “a” and “32b” are adjusted so as to be located at the ends of the two opposite side surfaces of the glass substrate 10.

Then, the two pins 32a and 32b are respectively brought into contact with the two opposite sides of the glass substrate 10 by the moving mechanism connected to the pins 32a and 32b, and the two opposite sides of the glass substrate 10 are brought into contact with each other. Is moved to the opposite end of the glass substrate 10. As a result, the two pins 32a and 32b rotate while rotating the coating film 12 formed on the two opposite side surfaces of the glass substrate 10.
Only the material can be physically scraped off to reduce the thickness of the coating film 12. At this time, it is preferable that the thickness of the coating film 12a left on the side surface of the glass substrate 10 be 1 μm or less.

Next, the pins 32a and 32b are
0, and the glass substrate 10 is rotated by 90 °. Then, in the same manner as described above, two pins 32 are attached to the ends of the other two opposite sides of the glass substrate 10.
The pins 32a and 32b are moved to the end of the opposite side surface of the glass substrate 10 by aligning the pins 32a and 32b. In this manner, by physically scraping only the coating film 12 formed on the four side surfaces of the glass substrate 10, the thickness of the coating film 12 formed on the side surface of the glass substrate can be reduced. As a result, the coating film 12 a covers the side surface of the glass substrate 10
Is formed in such a thin film thickness that the side surface of is not exposed. At this time, the coating film 12a is applied to the pins 32a and 32b by the glass substrate 1.
Since it is formed while being pressed in the direction of the 0 side surface, the adhesion to the side surface of the glass substrate 10 can be improved.

Therefore, in a later wet process,
Since the chemical does not penetrate into the interface between the glass substrate 10 and the release layer 12b, and the adhesion between the side surface of the glass substrate 10 and the release layer 20 can be improved, peeling of the release layer 20 can be prevented. Further, for example, even when the thickness of the coating film 12 is increased to 5 μm or more, the thickness of the coating film 12 on the side surface of the glass substrate 10 can be reduced to 1 μm or less by the same method as described above. Therefore, even when the coating film 12 is formed relatively thick on the glass substrate 10, the thick coating film 1 formed on the side surface of the glass substrate 10 in a later step
2b comes into contact with the transporting parts of the manufacturing apparatus, and the coating film 12b is peeled off, which may be a source of particles or a glass substrate 10b.
The coating film 12b on the side surface becomes too thick, the adhesion is reduced, and the possibility of peeling is eliminated.

Next, the coating film 12a whose side surface of the glass substrate 10 is thinned by the above-described method is heated at 260 ° C. for 10 minutes using a hot plate, dehydrated and closed to form a release layer 12b made of polyimide. To form Next, on the peeling layer 12b, at a substrate temperature of 180.degree.
A transparent conductive layer is formed by depositing TO (indium tin oxide) with a thickness of 150 nm.

Next, as shown in FIG. 1C, a resist film (not shown) is patterned by photolithography, the transparent conductive layer is etched using the resist as a mask, and the transparent electrode 14 is formed. Form. At this time,
Since the release layer 12b is formed so as to cover the side surface of the glass substrate 10, the developer used for patterning the resist film does not seep into the interface between the release layer 12b and the glass substrate 10, so that the release layer 12b Is not peeled off.

Next, as shown in FIG. 1D, a silica-based coating agent ZRS-5PH-
The intermediate layer 16 having a thickness of 700 nm is formed using No. 3 (manufactured by Catalyst Chemicals, Inc.). Next, as shown in FIG. 2A, a pigment-dispersion type photosensitive red resist is applied, exposed, and developed on the intermediate layer 16 to form a red color filter layer 18a in a red pixel portion.

Next, a pigment-dispersed photosensitive green resist is applied, exposed, and developed to form a green color filter layer 18c in the green pixel portion. Next, a pigment dispersion type photosensitive blue resist is applied, exposed, and developed to form a blue color filter layer 18c in the blue pixel portion. As described above, the color filter layer 1 made of red, green, and blue
8a, 18b and 18c are formed.

In this embodiment, after the intermediate layer 16 is formed, the color filter layers 18a, 18b, 18c
Are formed, the color filter layers 18a, 18b, and 18c are formed after forming the transparent electrode 14, and thereafter,
An intermediate layer 14 may be formed. Further, the transfer substrate 22 has a monochrome liquid crystal panel C that does not require color display.
If the purpose is to form an F substrate, the intermediate layer 16
The steps of forming the color filter layers 18a, 18b, 18c may be omitted.

Thereafter, as shown in FIG. 2B, an ultraviolet curable adhesive KR-400 (manufactured by Asahi Denka Co., Ltd.) is applied on the color filter layers 18a, 18b and 18c by a roll coater or the like to a thickness of 8 μm. Thus, the adhesive layer 20 is formed. Thereby, the release layer 12, the transparent electrode 14, the intermediate layer 1
6. The transfer substrate 22 having the transfer layer 26 including the color filter layers 18a, 18b, 18c and the adhesive layer 20 is completed.

According to the method of manufacturing transfer substrate 22 of the present embodiment, release layer 12b is formed on glass substrate 10 by spin coating so as to cover the side surface of glass substrate 10,
In addition, the release layer 12b on the side surface of the glass substrate 10 is adjusted to a thin film thickness that does not expose the side surface of the glass substrate 10.
That is, the glass substrate 1 in which the chemical solution is impregnated in a wet process in a step after the step of forming the release layer 12b.
0 and the release layer 12b, there is no interface.
The occurrence of peeling of b can be prevented. In addition, since the thickness of the release layer 12 formed on the side surface of the glass substrate 10 can be sufficiently reduced, dust generation due to contact with a member of a transport system in a manufacturing apparatus in a later process can be suppressed. it can. Further, since the release layer 12b is rubbed off while being physically pressed in the direction of the side surface of the glass substrate 10, the adhesion between the side surface of the glass substrate and the release layer 12b can be improved.

Next, the transfer substrate 22 manufactured by the above method
A method for transferring the transfer layer 26 of the above to a plastic substrate will be described. First, as shown in FIG.
Then, a plastic substrate 24 made of polyethersulfone resin having a thickness of 150 μm is attached to the substrate 2 via an adhesive layer 20.

Thereafter, UV irradiation of 3000 mJ / cm ² at a wavelength of 365 nm is performed from the plastic substrate 24 side with a high-pressure mercury lamp to cure the adhesive layer 24, which is a photocurable resin, and to bond the plastic substrate 24 to the transfer substrate 22. I do. Next, as shown in FIG. 4B, one end of the plastic substrate 24 bonded to the transfer substrate 22 is fixed to a roll 40 having a diameter of 200 mm, and the plastic substrate 24 is peeled off while rotating the roll 40. At this time, the transparent electrode 14, the intermediate layer 16, and the color filter layers 18a, 1 are peeled off from the interface between the substrate 10 of the transfer substrate 22 and the release layer 12b.
8b, 18c and the adhesive layer 20
Transferred to the side.

Next, the plastic substrate 24 to which these layers were transferred was subjected to a V1000 multi-stage tester (manufactured by Mori Engineering Co., Ltd.) under the conditions of a gas flow rate of 400 sccm, a pressure of 86 Pa, an RF output of 500 W and a temperature of 25 ° C. And etching for 15 minutes. Since the release layer 12 transferred to the plastic substrate 24 is an organic compound, it is easily etched and removed by oxygen plasma.

Thus, as shown in FIG. 5, a color formed by forming the adhesive layer 20, the color filter layers 18a, 18b, 18c, the intermediate layer 16, and the transparent electrode 14 on the plastic substrate 24 in this order from the bottom. The filter substrate 28 can be manufactured. The present invention may be embodied in various other forms without departing from its spirit or essential characteristics. Therefore, the above-described embodiment is merely an example in all aspects, and should not be interpreted in a limited manner. The scope of the present invention is defined by the claims, and is not limited by the embodiments.

[0033]

As described above, the present invention includes the step of forming a release layer, which is an insulating coating, so as to cover the side surface of the insulating substrate. According to this, there is no region where the release layer is patterned on the surface and the side surface of the substrate, and the surface and the side surface of the substrate are all covered with the release layer. In other words, there is no interface between the substrate and the release layer in which a chemical such as a developer soaks in the wet process in the step after the formation of the release layer.

Accordingly, since the peeling layer can be prevented from peeling off from the substrate, the production yield of the transfer substrate can be improved. Further, the present invention includes a step of reducing the thickness of the release layer, which is an insulating coating film formed on the side surface of the insulating substrate. When the thickness of the release layer formed on the insulating substrate is relatively large, the peripheral portion and the side wall portion of the substrate are even thicker. Therefore, a thick release layer formed on the side wall portion of the substrate in a later step. Is likely to be a source of particles when coming into contact with a member of a transport system of a manufacturing apparatus. Further, if the release layer on the side surface of the substrate is too thick, the adhesion to the side surface of the substrate is reduced, and there is a concern that the release layer may be peeled off from the side surface of the substrate.

According to the present invention, the release layer thickly formed on the side surface of the insulating substrate has such an insulating property that the side surface of the insulating substrate is not exposed, that is, the interface between the insulating substrate and the release layer does not appear. The film is thinned while being pressed in the direction of the side surface of the substrate. Therefore, even if the release layer on the side surface of the insulating substrate comes into contact with a member of a transport system in the manufacturing apparatus in a later step, a large amount of particles are not generated. In addition, the adhesion between the side surface of the insulating substrate and the release layer is improved, and peeling of the release layer can be prevented.

[Brief description of the drawings]

FIGS. 1A to 1D are cross-sectional views (part 1) illustrating a method of manufacturing a transfer substrate according to an embodiment in the order of steps;

FIGS. 2A and 2B are cross-sectional views (part 2) illustrating a method of manufacturing a transfer substrate according to an embodiment in the order of steps;

FIG. 3A is a perspective view showing a side surface processing apparatus for a substrate,
(B) is a sectional view of the same.

FIG. 4A is a cross-sectional view showing a state in which a plastic substrate is bonded to a transfer substrate, and FIG. 4B is a cross-sectional view showing how a transfer layer of the transfer substrate is transferred to the plastic substrate.

FIG. 5 is a cross-sectional view showing a plastic substrate having a transparent electrode or the like manufactured by transfer.

[Explanation of symbols]

 Reference Signs List 10 glass substrate, 12, 12a coating film, 12b release layer, 14 transparent electrode, 16 intermediate layer, 18a, 18b, 18c color filter layer, 20 adhesive layer, 22 transfer substrate, 24 plastic substrate, 26 transfer layer 28 color filter Substrate, 30 support base, 32a, 32b pin 34 substrate side surface treatment device, 40 rolls.

Continued on the front page (72) Inventor Ichiro Betsumiya 4-14-12 Koishikawa, Bunkyo-ku, Tokyo Kyodo Printing Co., Ltd. F-term (reference) 2H048 BA43 BA45 BA48 BA66 BB02 BB14 BB15 BB43 2H091 FA02Y FC12 GA01 GA03 LA30

Claims (8)

[Claims] A step of applying a coatable insulating film on the insulating substrate so as to cover a side surface of the insulating substrate, and forming a coating film; and forming the coating film on the side surface of the insulating substrate. A step of reducing the thickness of the film; a step of heating and curing the coating film to form a release layer; a step of forming a transparent conductive layer on the release layer; and a step of forming a transparent conductive layer on the transparent conductive layer. Forming an adhesive layer. 2. The method according to claim 1, further comprising a step of forming an intermediate layer after the step of forming the transparent conductive layer and before the step of forming the adhesive layer. A method for manufacturing a transfer substrate. 3. The step of forming the adhesive layer after the step of forming the transparent conductive layer and before the step of forming the intermediate layer, or after the step of forming the intermediate layer. The method according to claim 2, further comprising a step of forming a color filter layer before the step of performing the transfer. 4. The transfer substrate according to claim 1, wherein the insulating substrate is a glass substrate other than quartz glass, or a silicon-containing insulating film is formed on the glass substrate. Manufacturing method. 5. The method according to claim 1, wherein the coating is formed by a spin coating method. 6. The method according to claim 1, wherein the release layer is made of a polyimide resin. 7. The method according to claim 1, wherein the transparent conductive layer is patterned into an arbitrary shape. 8. The transfer layer comprising the release layer, the transparent conductive layer, and the adhesive layer is transferred to a transfer substrate made of a plastic material via the adhesive layer. 3. The method for manufacturing a transfer substrate according to item 1.