JP2003164789A - Method and apparatus for removing excess coating liquid at end of substrate surface - Google Patents

Abstract

(57) [Summary] [Problem] To remove a swelling portion of an application start portion and an application end portion of an organic film applied by a slit coating method,
The entire coating film has a uniform thickness. SOLUTION: An unnecessary portion of the organic film is vaporized and removed by irradiating a laser beam to a rising portion of an application start portion and an application end portion of an organic film applied on a substrate by a slit coating method.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for removing an excessive coating liquid from the edge of a substrate after the coating liquid has been applied to a single substrate such as a large glass substrate typified by an LCD color filter, and a method therefor. Relates to a device used in.

[0002]

2. Description of the Related Art Heretofore, a spin coating method has been known as a method of coating a coating liquid on a single substrate such as a large glass substrate represented by a color filter for LCD. This method has a drawback that the coating efficiency is as low as about 10% and that the coating film thickness becomes thick at the corners of the substrate. Furthermore, if the substrate is transported to the next step with the resist adhered to the edge of the glass substrate surface, the resist is transferred to the substrate regulation part and the stage part of the unit of the next process and the device is contaminated. By curing, this defect that causes dust can be solved, and as a method for efficiently applying the coating liquid to the single-wafer substrate, there are a knife coating method, a roll coating method, and a die coating method. There is a problem that the smoothness of the substrate surface must be equal to or lower than the coating accuracy in order to obtain a uniform film thickness. As a liquid coating method that can also solve this problem, a method of forming a coating liquid bead between the substrate surface and the coating head and relatively moving the substrate and the coating head to coat the substrate surface with the coating liquid is an international application PCT. / JP 94/00845 (International filing date: May 27, 1994).

[0003]

When the coating is carried out using the knife coating method, the roll coating method, the die coating method described above, or in the method described in the above-mentioned international application, the coating of the substrate is completed at the end of the coating. Excessive coating liquid remains on the edges, and due to this residual liquid, the uniform area of the coating film thickness is reduced, and partial poor drying occurs.
This is a factor that hinders the quality of the coating film.

Therefore, in the method disclosed in the above-mentioned international application, in order to remove the excess coating liquid, removal of the excess coating liquid by vacuum suction, removal by an absorptive roll, and dissolution removal by spraying an organic solvent are carried out. . However,
The removal of the coating liquid by vacuum suction takes time to perform over the entire coating width, and it is necessary to treat the absorbed excess coating liquid, which requires space for installing a pipe and a vacuum source. Further, the removal by the absorptive roll, especially when using an organic solvent-based coating liquid, there is a problem in terms of roll durability and washability, there is a problem that the material of the roll is limited, Has a problem that a large amount of cleaning solvent needs to be used since it must be cleaned after use, and a problem that it is mechanically complicated and requires a large installation space. Further, in the case of dissolving and removing by spraying with an organic solvent, there is a problem that a large amount of organic solvent is used.

The present invention has been made to solve the above-mentioned problems, and its purpose is to be inexpensive because the principle for evaporation of an excess coating solution is simple, to take less time to evaporate, and to evaporate. An object of the present invention is to obtain a method and an apparatus for removing the excess coating liquid from the end portion of the substrate surface, which can be surely performed and does not require evaporation atmosphere treatment or cleaning.

[0006]

According to a first aspect of the present invention, the excess coating liquid remaining near the edge of the substrate surface is removed at the end of coating the coating liquid on the substrate surface, or the coating liquid on the substrate surface is removed. After patterning through the photo process, a method for removing excess coating liquid on the edge of the substrate surface, wherein the light is applied to the edge of the substrate where the excess coating liquid remains after the coating liquid has been applied to the substrate surface or after patterning. Is sequentially irradiated to evaporate and remove the excess coating liquid.

According to a second aspect of the invention, in the method of the first aspect, a laser beam is used, and the laser beam is sent to the substrate so as to sequentially irradiate the excess coating liquid portion.

[0008]

In the method for removing excess coating liquid according to claim 1, a substrate having excess coating liquid on the edge of the substrate is formed at the end of liquid coating on the substrate surface or after patterning the coating liquid on the substrate surface through a photo process. The surface portion is irradiated and the excess coating liquid is evaporated.

In the method for removing excess coating liquid according to claim 2,
The reflector moves to the position where the reflected light is irradiated to the edge of the substrate, and then the light emitted from the light source is reflected by the reflector and is irradiated to the substrate surface portion with the excess coating liquid near the edge to cause excess light. The coating liquid is evaporated, and when there is an excess coating liquid portion in the different portion, the reflecting plate moves and the excess coating liquid is sequentially irradiated with laser light to vaporize the excess coating liquid.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a single-wafer substrate to be coated according to the present invention, which is an embodiment of the present invention with reference to the drawings, is typically an LCD.
It is a large glass substrate for color filters, and the liquid applied to the substrate is a photosensitive resin for forming a fine pattern on the glass substrate. Although the glass substrate is inflexible, the substrate treated in the present invention is not limited to such a glass substrate, and may be plastic, metal, paper, or the like, and the substrate itself may be flexible. As the liquid to be applied, various liquids such as an aqueous liquid and a solvent liquid can be used, and pigments, dyes, fillers, sensitizers, resins, additives and the like can be mixed alone or in combination.

(Embodiment 1) In FIG. 1, reference numeral 1 is a glass substrate, 550 × 670 mm, thickness 0.7 mm, NH
Techno-glass made non-alkali glass was used. The substrate 1 is vacuum-adsorbed on the substrate holder 2 by a mechanism (not shown). Reference numeral 3 denotes a laser light source, and in the present embodiment, a KrF excimer laser having a wavelength of 0.248 μm is used. The laser light emitted from the light source 3 is adjusted by the optical system 4 so as to have a desired beam diameter on the surface of the substrate 1. Reference numeral 5 is a mirror, and the light adjusted by the optical system 4 is reflected by this mirror and irradiated onto the surface of the substrate 1, and as a result, the excess coating liquid portion at the end of the substrate is evaporated by the laser light.

The laser light on the substrate has a circular shape with a spot diameter of 2 mm, an illuminance of 0.5 J / cm 2, and a light intensity of 200 H.
There is z. The mirror 5 is attached to the linear bearing 6,
The linear bearing 6 is capable of linearly moving the mirror 5 by rotating a motor 7 and is moved at a speed of 7 mm / sec. Furthermore, it is possible to scan along the edge of one side of the substrate 1. At this time, the distance from the light source 3 to the surface of the substrate 1 changes, but the optical system 4 is adjusted according to the movement of the mirror 5 so that the light radiated on the surface of the substrate 1 does not change in spot diameter and illuminance. After the removal of the excess coating liquid on one side of the substrate end by the above-described process, the substrate rotating mechanism 8
(See FIG. 2) 180
The process is rotated once to remove the excess coating liquid on the opposite end of the substrate in the same manner, and the whole process is completed.

FIG. 2 is a horizontal view of the device of the embodiment shown in FIG.

In the present embodiment, the substrate 1 is made of glass, and a black resist is applied on the surface thereof to form a black matrix pattern. The black resist on the substrate 1 was CK-A029 manufactured by Fuji Film Orin Co., Ltd. and had a film thickness of 2 μm. Since the slit type coating machine was used for coating the black resist, the excess coating liquid on the edge of the substrate is particularly intense at the coating start end and coating end end in the black resist coating direction. In this embodiment, since the black matrix pattern is formed by the photolithography process, particularly violent excess coating liquid portions at the coating start end and the coating end end in the black resist coating direction remain linearly. By rotating this 180 degrees by the substrate holder rotating mechanism 8, both the coating start end and the coating end end were alternately evaporated by laser light irradiation.

(Embodiment 2) FIG. 3 shows an embodiment in which a black resist is coated on the substrate 1 and the excess coating liquid on the four edges of the substrate is removed. Substrate 1 as in the first embodiment
Is vacuum-adsorbed on the substrate holder 2, and the laser light emitted from the light source 3 passes through the optical system 4 and is reflected by the mirror 10 in parallel to the surface of the substrate 1 in the direction of 90 degrees. It is reflected and irradiated on the substrate surface. The mirror 5, the linear bearing 6, the motor 7, and the mirror 10 are arranged on one stage so as to move at the same time, and are fixed by the motor 9 to the linear bearing 11 that moves along one side of the substrate 1 orthogonal to the bearing 6. Has been done. After the processing steps described in the first embodiment are completed, the substrate 1 is rotated by 90 degrees by the substrate rotating mechanism 8. As a result, the mirror 5 is displaced from the end of the substrate 1. At this time, the motor 9 is rotated and the linear bearing 11 is moved to move the mirror 5, the linear bearing 6, the motor 7, and the mirror 10 to the end of the substrate 1, and the linear bearing 6 is moved again as described in the first embodiment. Thus, the mirror 5 is moved along the edge of the substrate 1 and laser light is emitted from the light source 3 to remove the excess coating liquid portion at the edge of the substrate.

By performing the same steps on the remaining two sides, the removal processing of the excess coating liquid portion on all four sides of the substrate 1 is performed, and all steps are completed.

[0017]

As described above, according to the present invention, there are provided a method for removing excess coating liquid on a substrate by vacuum suction, an absorbent roll, and a method for dissolving and removing by spraying an organic solvent. In comparison, it is possible to reliably avoid problems such as residual coating liquid due to incomplete removal that tends to occur during vacuum suction and removal with an absorbent roll, and large consumption of organic solvent that occurs during removal by spraying the organic solvent.

Further, since no organic solvent is used, there is no danger of fire or human body and no environmental pollution occurs.

[Brief description of drawings]

FIG. 1 is a view of an excess coating liquid removing device of an end portion of a substrate surface according to the present invention as seen from above.

FIG. 2 is a side view of the excess coating liquid removing device of FIG.

FIG. 3 is a top view of a night device according to another embodiment of the excess coating liquid removing device of the present invention.

FIG. 4 is a side view of the excess coating liquid removing device of FIG.

[Explanation of symbols]

1 Substrate for which excess coating liquid is to be removed 2 substrate holder 3 light sources 4 Optical system 5 mirror 6 linear bearings 7 motor 8 Substrate rotation mechanism 9 motors 10 mirror 11 Linear bearing

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 21/027 H01L 21/30 577 F term (reference) 2H096 AA27 CA12 DA10 JA02 4D075 BB45Z BB48Z CA22 DA06 DB01 DB13 DB18 DB31 DC24 EA05 4F042 AA01 AA02 AA10 BA22 BA25 DB52 5F046 JA15 MA04

Claims (2)

[Claims] 1. A method for removing excess coating liquid at the edge of a substrate surface, which comprises removing excess coating liquid remaining at the edge of the substrate surface when coating of the coating liquid on the substrate surface is completed. After the coating is finished, the excess coating liquid is removed by irradiating the edge of the substrate on the side where the excess coating liquid remains to evaporate the excess coating liquid. 2. A laser beam is used as the irradiation light, and the laser beam is supported by the tip of a reciprocating member provided so as to be able to move back and forth along the edge of the substrate where the excess coating liquid remains. 2. The method for removing excess coating liquid from the end portion of the substrate surface according to claim 1, wherein each portion of the excess coating liquid on the substrate is irradiated with the light by reflecting it on the light reflecting plate.