JPH11235547A - Coating method and coating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the use quantity of coating liquid and to lower manufacturing cost. SOLUTION: On a substrate supporting base 2 arranged under a coating liquid feedign nozzle 3 having a linear opening 4, a substrate 1 to be coated with the coating liquid is mounted. The nozzle 3 and the supporting base 2 are relatively rotated taking an end part of the opening 4 as a center 6 of rotation. After the coating liquid is fed onto the substrate 1 by one rotation, the substrate 1 is subjected to plural rotations at high speed. In this way, the use quantity of the coating liquid can be sharply reduced to lower manufacturing cost. Because of rotary driving, an influence of driving vibration exerted on irregularity of coating film thickness can be reduced to improve a yield, and further, an installation space of the coating device can be decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a flat panel display (FPD) on a surface of various substrates such as a rectangular glass substrate and a circular semiconductor wafer.
The present invention relates to a coating method and a coating apparatus for applying a coating liquid to form various thin films such as a photoresist film and a protective film.

[0002]

2. Description of the Related Art For example, in a manufacturing process of an FPD, when a coating liquid is expensive, such as a pigment-dispersed resist film for forming a color filter, a roll using a roll is used in order to reduce the amount of the coating liquid as much as possible. Methods such as a coating method, a bar coating method using a bar, and a slit coating method in which a coating liquid is dropped from a linear (slit) opening of a coating liquid supply nozzle are used. It is to be noted that a method is also used in which the substrate is preliminarily applied by a slit coating method, then the substrate is main-coated by rotating a plurality of times at a high speed (spin coating method), and the coating liquid is uniformly diffused on the substrate surface.

[0003] With respect to such a coating technique, for example,
JP-A-60-89925, JP-A-63-156320
JP-A-4-118073, JP-A-4-33211
6, JP-A-6-151296, JP-A-8-12991
No. 04, JP-A-8-213308 and the like.

Japanese Patent Application Laid-Open No. 60-89925 discloses a photoresist coating method using a linear opening and a spin coating method. JP-A-63-156320 describes a coating method in which a resist is supplied from a linear opening while rotating a substrate, and then the substrate is rotated again. Japanese Patent Application Laid-Open No. 4-118073 discloses an apparatus in which a coating liquid is dripped from a linear opening, the opening and the substrate are relatively linearly moved in a straight line, and then the substrate is rotated at a high speed. Are listed. Japanese Patent Application Laid-Open No. 4-332116 describes an apparatus in which a coating liquid is dropped from a linear opening while slowly rotating a substrate, and then the substrate is rotated at a high speed. Japanese Patent Application Laid-Open No. 6-151296 discloses a method in which a coating liquid is supplied from a linear opening onto a stationary substrate and the opening is moved linearly along the surface of the substrate to apply the coating liquid. A method is described in which a coating liquid is supplied from a hole-shaped opening and the opening is moved along the substrate surface in the radial or diametrical direction of the substrate to perform coating. Japanese Patent Application Laid-Open No. 8-129104 discloses a method in which a coating solution is preliminarily applied to a substrate by wire bar coating, roll coating, die coating, or the like, which is easy to control the film thickness, and then the substrate is rotated to perform the main coating. Are listed. JP-A-8-21
Japanese Patent No. 3308 describes a method in which a coating liquid is supplied from a linear opening disposed on a substrate, the opening is moved relatively in parallel with the substrate, and then the substrate is rotated.

[0005]

In a spin coating method in which a coating liquid is dripped from a cylindrical or conical coating liquid supply nozzle to a central portion of a substrate, and the substrate is rotated a plurality of times at a high speed to form a thin film, the coating is performed. Since the liquid is scattered to the outside of the substrate and 90% or more of the lower amount of the coating liquid is rejected as waste liquid, it is inferior in reducing the amount of the coating liquid used.

[0006] Further, in the slit coating method and the spin coating method in which a linear opening and a substrate are relatively linearly moved in parallel and relatively moved, and then the substrate is rotated a plurality of times at high speed to form a rectangular thin film, It is excellent in that the amount of the coating liquid used can be reduced, but the vibration during the parallel movement greatly affects the unevenness of the coating film thickness. Further, since a coating liquid supply nozzle having a linear opening or a driving mechanism for moving the substrate in parallel is provided, the installation space of the coating apparatus is increased.

SUMMARY OF THE INVENTION An object of the present invention is to provide a coating method and a coating apparatus in which the amount of a coating liquid used can be reduced, the influence of driving vibration on the coating film thickness unevenness is small, and the installation space of the coating apparatus can be reduced. .

[0008]

In order to solve the above-mentioned problems, a coating method according to the present invention is characterized in that, while a coating solution is dropped from a linear opening, the opening and a substrate disposed thereunder are connected to the opening. The coating liquid is supplied onto the substrate by relatively rotating the end of the substrate about the rotation center, and then the substrate is rotated a plurality of times at high speed.

Further, the length of the linear opening is slightly smaller than a half of a short side of the rectangular substrate or a radius of the circular substrate.

The number of rotations for supplying the coating liquid may be one rotation, slightly less than one rotation (ie, slightly before the initial position), or slightly more than one rotation (ie, one rotation).
(Slight overlap) or multiple rotations.

In addition, the width of the opening with respect to the distance from the center of rotation is adjusted so that the discharge amount of the coating liquid from the opening with respect to the distance from the center of rotation is constant. It is characterized in that it is set in proportion to the relative speed.

[0012] Further, the present invention is characterized in that the substrate is rotated to supply the coating liquid while the opening is kept stationary.

[0013] Further, the present invention is characterized in that the opening is rotated to supply the coating liquid while the substrate is stationary.

Further, the coating apparatus of the present invention comprises: a coating liquid supply nozzle having a linear opening; and a substrate support stand disposed under the coating liquid supply nozzle for mounting and holding a substrate on which the coating liquid is coated. A rotation mechanism for relatively rotating the coating solution supply nozzle and the substrate support base around an end of the opening as a rotation center.

The length of the linear opening is slightly smaller than a half of a short side of the rectangular substrate or a radius of the circular substrate.

In addition, the width of the opening with respect to the distance from the center of rotation is adjusted so that the discharge amount of the coating liquid from the opening with respect to the distance from the center of rotation is constant. It is characterized in that it is set in proportion to the relative speed.

Further, the distance between the lower end of the coating liquid supply nozzle and the substrate is set such that the lower end of the coating liquid supply nozzle comes into contact with the coating liquid supplied onto the substrate when the coating liquid is supplied. And

[0018] Further, the present invention is characterized in that the coating liquid is supplied by rotating the substrate support while the coating liquid supply nozzle is stationary.

Further, the coating liquid is supplied by rotating the coating liquid supply nozzle while the substrate support is stationary.

In the present invention, the linear opening and the substrate disposed thereunder are relatively rotated about the end of the opening to drop the coating liquid, and the film thickness is initially thin and uniform on the substrate. After forming a large circular coating film, the substrate is rotated multiple times at high speed to form a thin film with a uniform thickness. In comparison, the amount of application liquid used can be reduced. Further, since the linear opening and the substrate are rotated in parallel and not relatively moved in a straight line, the influence of the driving vibration on the coating film thickness unevenness can be reduced, and a thin film having a uniform film thickness can be formed. In addition, since a rotating mechanism may be provided instead of a linear opening or a driving mechanism for moving the substrate in parallel, the installation space of the coating apparatus can be reduced.

The above-mentioned patent publications, which describe the technology related to the present invention, all disclose a configuration in which a linear opening characteristic of the present invention is relatively rotated about an end of the opening. Not listed.

[0022]

Embodiments of the present invention will be described below in detail with reference to the drawings. In the drawings described below, those having the same functions are denoted by the same reference numerals, and the repeated description thereof will be omitted.

FIG. 1A is a schematic perspective view of a main part of a coating apparatus according to an embodiment of the present invention, and FIG. 1B is a plan view showing an opening of a coating liquid supply nozzle and a coating liquid supply area on a substrate. .

In FIG. 1A, reference numeral 1 denotes a glass substrate to which a coating liquid is applied, 2 denotes a substrate support (platen chuck), 3 denotes a coating liquid supply nozzle, 6 denotes a rotation center (rotation axis) of the substrate support 2, 4B, reference numeral 4 denotes an opening of the nozzle 3, and 5 denotes an initial application area (application liquid supply area).

The coating apparatus of the present embodiment includes a coating liquid supply nozzle 3 having a line (slit) -shaped opening 4 and a glass substrate 1 disposed below the nozzle 3 for coating the coating liquid.
The flatness for holding by vacuum suction is ± 0.05 mm, for example.
And a rotation drive unit (not shown) for rotating the substrate support base 2 with the end of the opening 4 of the nozzle 3 as the center of rotation 6.

The glass substrate 1 has a rectangular shape, for example, for producing an LCD (liquid crystal display element), and has a vertical length W560.
mm × width L650 mm. The length of the linear opening 4 is １ ／ of the short side W of the glass substrate 1 (the radius of the substrate when the substrate is circular like a semiconductor wafer) 28
It is 270 mm slightly smaller than 0 mm. Substrate support 2
The application liquid is supplied onto the substrate 1 by one rotation (initial application).

The width T of the linear opening 4 is represented by T ₁ / r in proportion to the relative speed of the substrate 1 to the nozzle 3 when the coating liquid is supplied, where r is the radius (ie, the distance from the rotation center 6).
Set T ₂ = r ₁ / r ₂ . Here, T ₁ and T ₂ are the widths of the openings 4 at the radii r ₁ and r ₂ , respectively. Thereby, the discharge amount of the coating liquid from the opening 4 with respect to the distance from the rotation center 6 becomes constant, and the thickness of the coating liquid supplied onto the substrate 1 can be made uniform. The shape of the opening 4 (the rate of change of the width) is exaggerated in FIG.

In the present embodiment, the distance between the lower end of the coating liquid supply nozzle 4 and the surface of the substrate 1 is set such that the lower end of the nozzle 3 contacts the coating liquid supplied onto the substrate 1 when the coating liquid is supplied.
It is set to 200 to 300 μm.

In the present embodiment, the substrate support 2 is rotated at a rotational speed of 120 mm / min.
The coating liquid is supplied at 360 ° at 0 mm, that is, one rotation.

The substrate 1 is vacuum-adsorbed to the substrate support 2 and a constant posture is maintained. When the substrate support 2 is rotated once while supplying a predetermined coating liquid to the nozzle 3, as shown in FIG. 1B, a large circular coating film 5 having a radius equal to the length of the opening 4 is formed.
Is formed. The area of the coating film 5 is about 63% of the entire area of the substrate 1. Thereafter, the nozzle 3 moves to a standby position (not shown), and the substrate support 2 holds the substrate 1 by vacuum suction while rotating at a rotational speed of 500 rpm to 15 rpm.
Make multiple high-speed rotations at 00 rpm. As a result, the coating liquid on the substrate 1 extends to the edge of the substrate 1 and excess coating liquid is
And a thin coating film having a uniform thickness and a rectangular shape is formed on the entire substrate 1 (main coating).

As described above, in the present embodiment, the coating liquid is dropped on the substrate 1 by rotating the glass substrate 1 around the end 6 of the opening 4, and the film thickness is thin and uniform on the substrate 1 from the beginning. After forming the large circular coating film 5, the substrate 1 is rotated a plurality of times at a high speed to form a thin film having a uniform thickness. Therefore, a large amount of a coating solution is dripped at the center of the substrate, and the substrate is rotated at a high speed. In comparison with the use amount of the coating liquid of about 50 g, the amount can be reduced to about 20 g, that is, about 60%. Therefore, the manufacturing cost can be reduced, and this is particularly effective for an expensive color filter.

In addition, since the substrate 1 is rotated without moving the linear opening and the substrate in a straight line relative to each other in parallel, the influence of driving vibration on the coating film thickness unevenness can be reduced, and the film thickness can be made uniform. A thin film can be formed. Therefore, the production yield can be improved.

In addition, since it is sufficient to provide a rotating mechanism without providing a drive mechanism for moving the linear opening or the substrate in parallel, the installation space of the coating apparatus can be reduced. Further, the present coating apparatus can be realized by slightly modifying the existing spin coating apparatus.

Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the above-described embodiments, and it is needless to say that various modifications can be made without departing from the gist of the present invention. is there. For example, in the above-described embodiment, the application liquid is supplied by rotating the substrate support 2 while the application liquid supply nozzle 3 is stationary.
It is needless to say that the application liquid may be supplied by rotating the application liquid supply nozzle 3 once while the is stationary. When supplying the coating liquid, the support 2 or the nozzle 3 may be rotated twice or more. Furthermore, it goes without saying that the present invention is not limited to a glass substrate for manufacturing LCDs, but is applicable to application to various substrates such as semiconductor wafers for manufacturing semiconductor devices, and application and formation of various thin films.

[0035]

As described above, according to the coating method and the coating apparatus of the present invention, the amount of the coating liquid used can be greatly reduced, and the manufacturing cost can be reduced. In addition, since the apparatus is driven by rotation, it is possible to reduce the influence of the drive vibration on the coating film thickness unevenness, improve the yield, and further reduce the installation space of the coating apparatus.

[Brief description of the drawings]

FIG. 1A is a schematic perspective view of a main part of a coating apparatus according to an embodiment of the present invention, and FIG. 1B is a plan view showing an opening of a coating liquid supply nozzle and a coating liquid supply area on a substrate.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate, 2 ... Substrate support, 3 ... Coating liquid supply nozzle, 4
... opening, 5 ... initial application area, 6 ... center of rotation.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI H01L 21/027 H01L 21/30 564C

Claims (11)

[Claims] 1. While dropping a coating liquid from a linear opening,
After the coating liquid is supplied onto the substrate by relatively rotating the opening and the substrate disposed thereunder about the end of the opening as a center of rotation, the substrate is rotated a plurality of times at a high speed. Coating method. 2. The coating method according to claim 1, wherein the length of the linear opening is slightly smaller than a half of a short side of the rectangular substrate or a radius of the circular substrate. . 3. The width of the opening with respect to the distance from the center of rotation is set so that the discharge amount of the coating liquid from the opening with respect to the distance from the center of rotation is constant. The coating method according to claim 1, wherein the setting is made in proportion to the relative speed. 4. The coating method according to claim 1, wherein the substrate is rotated to supply the coating liquid while the opening is kept stationary. 5. The coating method according to claim 1, wherein said coating liquid is supplied by rotating said opening while said substrate is stationary. 6. A coating liquid supply nozzle having a linear opening, a substrate support table disposed under the coating liquid supply nozzle for mounting and holding a substrate on which a coating liquid is to be coated, A coating mechanism comprising: a rotation mechanism configured to relatively rotate the substrate support base around an end of the opening as a rotation center. 7. A coating apparatus according to claim 6, wherein a length of said linear opening is slightly smaller than a half of a short side of said rectangular substrate or a radius of said circular substrate. . 8. The width of the opening with respect to the distance from the rotation center is set so that the discharge amount of the coating liquid from the opening with respect to the distance from the rotation center is constant. The coating apparatus according to claim 6, wherein the setting is made in proportion to the relative speed. 9. A distance between the lower end of the coating liquid supply nozzle and the substrate is set such that the lower end of the coating liquid supply nozzle comes into contact with the coating liquid supplied onto the substrate when the coating liquid is supplied. The coating device according to claim 6, wherein 10. The coating apparatus according to claim 6, wherein the coating liquid is supplied by rotating the substrate support while the coating liquid supply nozzle is stationary. 11. The coating apparatus according to claim 6, wherein the coating liquid is supplied by rotating the coating liquid supply nozzle while the substrate support is stationary.