JPH10261578A - Resist-applying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the amount of resist liquid to be disposed by providing a leveling apparatus for spreading a dripped resist liquid for a device for applying the resist liquid to a substrate by dripping the resist liquid on a substrate on a rotary chuck and shaking off a surplus resist liquid by rotation. SOLUTION: When a nearly circular wafer 2 is centered and is placed on a rotary chuck 1 and is fixed by vacuum suction, a nozzle 3 drips a specific amount of resist liquid from the upper part of the center of the wafer 2. However, the amount of drip is relatively small. The nozzle 3 retracts, at the same time, a blade 4 advances to the center of the wafer 2 with a small gap, a rotary chuck 1 is rotated at a low speed, and at the same time the blade 4 moves in the radius direction of the wafer 2 and levels the resist liquid toward the outer periphery of the wafer 2, and levels and spreads the resist to the outer periphery and then retracts, thus reducing the amount of dripping of the resist liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for applying a resist solution to a substrate used in a semiconductor device manufacturing process or the like.

[0002]

2. Description of the Related Art An example of a conventional resist coating apparatus for applying a resist solution to a semiconductor wafer, for example, will be described. FIG. 3 is a side view of a main part of a conventional resist coating apparatus. When the wafer 2 is placed on the rotary chuck 1 and vacuum chucked,
The nozzle 3 moves from the standby position to the center of the rotary chuck 1 and drops a predetermined amount of resist solution onto the wafer which is stopped or rotating at a low speed. Thereafter, the rotating chuck is rotated at a medium speed to spread the dropped resist solution over the entire surface of the wafer, and is switched to a high-speed rotation to shake off excess resist solution, thereby performing coating with a predetermined thickness.

[0003]

However, in such a conventional resist coating apparatus, the resist liquid dropped at the center of the wafer does not always spread uniformly, and if the amount of the dropped liquid is small, a portion that cannot be coated occurs. In order to prevent the unapplied portion from being produced with good reproducibility, it is necessary to increase the dripping amount sufficiently. Therefore, 10 times or more of the resist solution actually applied to the wafer is discarded. Therefore, the present invention provides a resist coating apparatus in which the amount of the resist solution to be discarded is reduced.

[0004]

SUMMARY OF THE INVENTION The present invention is directed to a resist coating apparatus for applying a resist solution to a substrate by dropping the resist solution onto a substrate on a rotary chuck and rotating to shake off excess resist solution. It is characterized by having a leveling device for spreading the liquid. According to the above apparatus, after the resist liquid is dropped on the substrate, the rotating chuck is rotated at a high speed to shake off the excess resist liquid after almost the entire substrate is spread by a leveling tool, so that the amount of the resist liquid dropped is reduced. However, the generation of unapplied portions is eliminated.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A resist coating apparatus according to the present invention will be described with reference to the drawings. FIG. 1 is a side view of a main part of an embodiment of the present invention. The rotary chuck 1 and the nozzle 3 are the same as in the conventional apparatus. The blade 4 is characteristically provided as an example of the leveling device. The blade 4 is a substrate such as a wafer 1
Liquid (not shown) dropped from nozzle 3 at the center of
Has the function of spreading the entire surface of the wafer. The blade 4 moves a predetermined gap (for example, 10 μm) from the surface of the wafer to a position above the center of the wafer 2 from a predetermined retreat place after dropping the resist droplet.
(Several tens of μm) and moves while keeping a gap in the radial direction of the wafer, and spreads the resist solution over the entire surface of the wafer and retracts. The blade 4 should be made of a material that does not wet the resist solution, such as a fluorine resin.

Next, the structure of the apparatus and the blade 4 will be described in further detail with the description of the operation of the apparatus. When a substantially circular wafer 2 is centered and placed on the rotary chuck 1 and fixed by vacuum suction, the nozzle 3 advances from the standby position to above the center of the wafer 2 and a predetermined amount of resist solution (not shown) ) Is dropped. However, the drop amount is smaller than that of the conventional apparatus. When the dropping of the resist solution is completed, the nozzle 3 retracts to a predetermined retreat location. The retreat location is set at a resist solvent atmosphere so that the resist solution does not dry at the tip of the nozzle 3, or the tip of the nozzle 3 is immersed in a solvent. As the nozzle 3 retreats, the blade 4 advances from a predetermined retreat location to the center of the wafer 2 with a small gap as shown in the plan view of the main part of the apparatus shown in FIG.
Then, the rotating chuck 2 rotates at a low speed, and the blade 4 moves in the radial direction of the wafer 2 to level a resist solution (not shown) toward the outer periphery of the wafer 2. The blade 4 is arranged in a direction inclined from the circumferential direction, so that the side where the wafer 2 first comes close by rotation is close to the center of the wafer, and the side that comes close later is far from the center so that the resist solution moves outward. . Then, the blade 4 spreads the resist uniformly to the outer periphery of the wafer 2 and then retreats to a predetermined standby place.
In order to wash the resist solution adhering at the evacuation area, the resist solution is immersed in a solvent that dissolves the resist solution. And blade 4
And the rotating chuck 1 rotates at a high speed so that the excess resist solution on the wafer 2 is swept off to obtain a uniform coating thickness.

According to this embodiment, the blade 4 as a leveling tool evens out the resist solution over the entire surface of the wafer, and the blade 4 is made of a material that does not wet the resist solution. The amount of the resist solution dropped can be reduced.

According to the above embodiment, the blade 4 is used as the leveling tool, but a soft brush can be used. The material of the brush is preferably not wet with the resist solution, from the viewpoint of reducing the take-out of the resist solution.

If a soft brush is used, it may be in contact with the wafer, so that there is an advantage that the trouble of adjusting the height every time the thickness of the wafer applied to obtain a fine gap like a blade is changed is eliminated. However, the amount of the resist liquid attached to the brush and held is larger than that of the blade.

[0010]

As described above, according to the present invention,
The amount of the resist solution dropped is reduced, and the consumption of the resist solution is reduced.

[Brief description of the drawings]

FIG. 1 is a side view of a main part of an embodiment of the present invention.

FIG. 2 is a plan view thereof.

FIG. 3 is a side view of a main part of a conventional device.

[Explanation of symbols]

 1 Rotary chuck 2 Wafer (substrate) 4 Blade (leveling instrument)

Claims (3)

[Claims] In a resist coating apparatus for applying a resist solution to a substrate by dropping the resist solution onto a substrate on a rotary chuck and rotating to shake off excess resist solution, an apparatus for spreading the dropped resist solution is provided. A resist coating apparatus, comprising: 2. The resist according to claim 1, wherein said leveling tool is a blade which moves from the center to the outside with a gap on the surface of said substrate when said substrate on which the resist solution is dropped is rotating at a low speed. Coating device. 3. The resist coating apparatus according to claim 1, wherein said leveling tool is a brush which moves outward from a center on the surface of the substrate when the substrate on which the resist solution is dropped is rotating at a low speed. .