JPH11150056A - Resist applicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist applicator which can form a uniform resist film by preventing the occurrence of voids in the resist film, and which can be downsized itself. SOLUTION: A resist applicator is equipped with a vibration application means 31 for giving vibration to a wafer 22 placed on a spin chuck 23, and the vibration application means 31 possesses a vibration stage 32 where at least the spin chuck 23 is placed, a cam receiving face 34 provided at the vibration stage 32, a cam 36 being fixed to a rotary shaft 35 for vibration while abutting on the cam receiving face 34 so as to vibrate the vibration stage 32, a driving means 37 for rotating the cam 36 through the rotary shaft 35 for vibration, and an energizing member 39 or energizing the vibration stage 32 so that the cam receiving face 34 and the cam 36 may abut on each other, being provided between the vibration stage 32 and a fixed face 38.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist coating apparatus, and more particularly to a spin resist coating apparatus.

[0002]

2. Description of the Related Art Conventionally, in a process of manufacturing a semiconductor integrated circuit, a spin type resist coating apparatus has been employed in order to form a uniform resist film on a wafer surface.
In this apparatus, a resist solution is dropped on a horizontal wafer surface, and the wafer is rotated to form a uniform resist film on the wafer surface.

However, in such a spin-type resist coating apparatus, it is difficult to set the rotation speed of the wafer, and it is particularly easy to set the rotation speed to a high value. There is a problem that the film thickness becomes 1 to 1.5 times the film thickness of the resist at the central portion of the wafer, and a uniform resist film cannot be formed.

[0004] In order to solve the above-mentioned problems, for example, a resist coating apparatus disclosed in Japanese Patent Application Laid-Open No. H2-220429 has been proposed. This conventional resist coating apparatus will be described with reference to the drawings.

In FIG. 4, a resist coating apparatus includes a spin chuck 2 on which a wafer 7 is mounted, a rotating shaft 3 fixed to the spin chuck 2 for rotating the spin chuck 2, and a belt 8. It comprises a motor 6 for rotating the shaft 3, a container 9 for storing water 10, and an ultrasonic generator 11 arranged so as to contact the bottom of the container 9. The container 9 is arranged below the spin chuck 2 so that the water 10 contacts the bottom surface of the spin chuck 2.

Next, the operation of the resist coating apparatus will be described. First, after placing the wafer 7 on the spin chuck 2, the ultrasonic generator 11 is started to generate ultrasonic vibration. The ultrasonic vibration is transmitted to the spin chuck 2 via the container 9 and the water 10, and the ultrasonic vibration is applied to the wafer 7. Further, the motor 6 is rotated, and the spin chuck 2 is rotated at 50 to 100 rpm via the belt 8 and the rotating shaft 3.
Rotate at a speed of m.

Next, a resist solution is dropped on the surface of the wafer 7, and after the resist solution spreads on the surface of the wafer 7,
The spin chuck is rotated at a high speed (1000 to 2000 rpm), and after about 1 minute, the spin chuck 2 and the ultrasonic generator 11 are stopped.

According to the conventional resist coating apparatus, when applying the resist liquid, the ultrasonic vibration is applied to the rotating wafer 7, so that the resist liquid dropped on the surface of the wafer 7 spreads evenly, and The difference in the thickness of the resist between the central portion and the circumferential portion can be reduced, and a uniform resist film can be formed.

[0009]

However, in the above-described resist coating apparatus, the gas dissolved in the resist liquid (gas mixed from the atmosphere of the resist coating, or the gas for producing the resist liquid) is generated by ultrasonic vibration. Gas mixed from the atmosphere at the time, or a gas dissolved in the raw material of the resist solution) becomes bubbles in the resist solution, and the ultrasonic vibration has a relatively small amplitude, so that the bubbles cannot be removed. There is a problem that voids are generated in the resist film.

In addition, even when gas in the atmosphere is entrained by the dropping of the resist solution and bubbles are mixed in the resist solution, the ultrasonic vibration has a relatively small amplitude, so that the bubbles cannot be removed. There was also a problem that voids were generated therein.

Further, in the above-described resist coating apparatus, the ultrasonic generator 11 and the container 9 storing the water 10 are required to vibrate the spin chuck 2, and the resist coating apparatus itself becomes large. There was a problem that would.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and can prevent the generation of voids in a resist film to form a uniform resist film.
An object of the present invention is to provide a resist coating apparatus capable of reducing the size of the apparatus itself.

[0013]

In order to achieve the above object, the present invention employs the following constitution.

The resist coating apparatus according to the present invention is a resist coating apparatus provided with a vibration applying means for applying vibration to a wafer mounted on a spin chuck, wherein the vibration applying means comprises at least the spin applying means. A vibration table on which a chuck is mounted, a cam receiving surface provided on the vibration table, and a cam fixed to a vibration rotary shaft while abutting on the cam receiving surface to vibrate the vibration table, Driving means for rotating the cam via the vibration rotary shaft and the vibration table are provided between the vibration table and a fixed surface so that the cam receiving surface and the cam come into contact with each other. And a biasing member for biasing.

[0015]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2, a resist coating apparatus 21 of the present invention includes a spin chuck 23 on which a wafer 22 is mounted, a wafer rotating shaft 24 for rotating the spin chuck 23, and a wafer. Rotating shaft 24
A wafer motor 25 for rotating the spin chuck 23 while being connected to the motor and a vibration applying means 31 for applying vibration to the wafer 22 are provided. Wafer 22
After being mounted on the spin chuck 23, the pressure inside the suction hole (not shown) formed in the surface of the spin chuck 23 is reduced, and the suction hole is adsorbed on the spin chuck 23.

The vibration applying means 31 includes a vibration table 32 on which the wafer motor 25 is mounted, and a cam receiving surface 34 formed at the tip of a connecting rod 33 protruding below the vibration table 32.
A cam 36 fixed to the vibration rotary shaft 35 while being in contact with the cam receiving surface 34 in order to vibrate the vibrating table 32;
A vibration motor 37 as a driving means for rotating the cam 36 via the vibration rotation shaft 35, and a coil spring 3 as an urging member provided between the vibration table 32 and the fixed surface 38
9 are provided. The vibration table 32 is configured to slide in a direction parallel to the upper surface of the wafer 2 by, for example, a rail (not shown). Further, the fixing surface 38 may be a frame or the like of the resist coating device 21.

A coil spring 39 as an urging member is used to urge the vibrating table 32 rightward in the drawing so that the cam receiving surface 34 and the cam 36 come into contact with each other.
It is erected between them. Further, on the vibration table 32, a wafer motor 25, a wafer rotating shaft 24, and a spin chuck 23 on which the wafer 22 is mounted are mounted. The cam 36 may have any shape as long as the cam receiving surface 34 vibrates in the left-right direction in the figure by the rotation thereof, but a plate cam, a circular cam, or the like is preferable. The amplitude and frequency of the vibration to be generated
6 can be changed arbitrarily by adjusting the shape.

Next, the operation of the resist coating apparatus 21 will be described. 1, 2 and 3, first, the wafer 22 is placed on the spin chuck 23, and then the spin chuck 23 is rotated by the wafer motor 25. Next, a resist solution is dropped on the surface of the wafer 22,
After the resist liquid has spread on the surface of the wafer 22, the spin chuck 23 is rotated at a higher speed.

At the same time as the spin chuck 23 is rotated at a high speed, the vibration motor 37 is rotated. The rotation of the vibration motor 37 is transmitted to the cam 36 via the vibration rotation shaft 35. The cam receiving surface 34 is always in contact with the cam 36 by the coil spring 39 which is an urging member.
, That is, in a direction parallel to the upper surface of the wafer 2.

In this manner, the vibration of the vibrating table 32 is transmitted to the wafer 22 via the spin chuck 23, and the resist solution dropped on the surface of the wafer 22 spreads evenly, and the center portion and the circumferential portion of the wafer 22 are spread. In this case, the difference in the thickness of the resist becomes smaller.

In the above-described resist coating apparatus 21, vibration is generated by the rotating cam 36 and the cam receiving surface 34, and the vibration has an amplitude larger than that of the ultrasonic vibration due to the shape of the cam 36. In addition, it is possible to remove bubbles mixed in the resist solution, and to prevent the occurrence of voids in the resist film. In order to obtain the same frequency as the ultrasonic vibration, the rotational speed of the vibration motor 37 may be increased. Further, by appropriately adjusting the shape of the cam 36, the amplitude and frequency of the generated vibration can be arbitrarily changed.

In the resist coating apparatus 21, the vibration applying means 31 for vibrating the wafer 22 includes the vibration table 32, the cam 36, the vibration motor 37 and the like. The size of the resist 31 can be reduced, and the resist coating device 21 itself can be reduced in size.

The technical scope of the present invention is not limited to the above embodiment, and various changes can be made without departing from the spirit of the present invention. For example, in the present embodiment, the cam receiving surface 34 is formed at the tip of the connecting rod 33 protruding from the lower part of the vibration table 32, but is not limited to this, and is formed on the side surface of the vibration table 32. May be.

[0025]

As described in detail above, in the resist coating apparatus of the present invention, at least a vibration table on which the spin chuck is mounted, a cam receiving surface provided on the vibration table, In order to vibrate the shaking table, a cam fixed to a vibration rotating shaft while being in contact with the cam receiving surface, a driving unit for rotating the cam via the vibration rotating shaft, and the vibration table A vibration applying unit that is provided between the fixed surface and the urging member for urging the vibration table so that the cam receiving surface and the cam come into contact with each other; Since it is possible to increase the size and remove bubbles mixed in the resist solution, it is possible to prevent generation of voids in the resist film and to form a uniform resist film.

In the resist coating apparatus of the present invention, since the vibration applying means is composed of the vibration table, the cam and the driving means (vibration motor), the size of the vibration applying means can be reduced. It is possible to reduce the size of the resist coating apparatus itself.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a main part of a resist coating apparatus according to an embodiment of the present invention.

FIG. 2 is a front view showing a main part of a resist coating apparatus according to an embodiment of the present invention.

FIG. 3 is a front view for explaining the operation of the resist coating apparatus according to the embodiment of the present invention.

FIG. 4 is a cross-sectional view showing a main part of a conventional resist coating apparatus.

DESCRIPTION OF SYMBOLS 21 Resist coating device 22 Wafer 23 Spin chuck 24 Wafer rotating shaft 25 Wafer motor 31 Vibration applying means 32 Shaking table 33 Connecting rod 34 Cam receiving surface 35 Vibrating rotating shaft 36 Cam 37 Drive means (vibration 38) Fixed surface 39 Biasing member (coil spring)

Claims (1)

[Claims] 1. A resist coating apparatus provided with a vibration applying means for applying vibration to a wafer mounted on a spin chuck, wherein the vibration applying means comprises at least a vibration on which the spin chuck is mounted. A table, a cam receiving surface provided on the vibrating table, a cam fixed to a vibrating rotary shaft while abutting on the cam receiving surface to vibrate the vibrating table, and via the vibrating rotary shaft. A driving means for rotating the cam, and an urging member provided between the shaking table and a fixed surface, for urging the shaking table so that the cam receiving surface and the cam come into contact with each other. A resist coating apparatus, comprising: