JPH10135101A - Spin coater - Google Patents

Abstract

(57) [Problem] To provide a spin coater in which the thickness of a resist film does not vary within a wafer surface or between wafers. A spin coater (20) includes a spin chuck (1).
4, a spin cup 22, and a spin cup 20. The spin cup 22 includes an inner wall plate 24 and an outer wall plate 26, and a heat transfer tube 28 disposed between the two wall plates at equal intervals in a serpentine shape. When a resist film is formed on the wafer 12, temperature-regulated water is passed through the heat transfer tube 28, and then a resist film is applied in the same manner as in the related art, and a cleaning liquid is sprayed on the resist film formed on the periphery and the back side of the wafer. Dissolve and remove the membrane. As a result, even if the cleaning liquid scatters into the spin cup 22 and takes heat of vaporization, the ambient temperature inside the spin cup 22 is maintained within a predetermined temperature range. Therefore, since the temperature of the wafer does not decrease in the process of sequentially coating the wafer, the resist film can be formed uniformly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spin coater, and more particularly to an improved spin coater in which a resist film is applied such that the thickness of the resist film is uniform within a wafer surface or between wafers. It is.

[0002]

2. Description of the Related Art In the manufacture of a semiconductor device, when a resist film is applied on a wafer, the coating is generally performed using a spin coater. FIG. 2 is a side sectional view of a conventional spin coater. A conventional spin coater 10 holds a wafer 12 on a horizontal holding surface and rotates the wafer 12 around a vertical rotation axis, a nozzle 15 for dropping a resist solution onto the wafer, and a cleaning liquid for the wafer. Cleaning nozzle 17 sprayed on the lower surface of wafer 12 and spin cup 1 provided to surround wafer 12
6 and a drain pipe 18 connected to and connected to the inside of the spin cup 16. The spin cup 16 is usually made of stainless steel in order to make the attached resist solution easy to wash.

In order to form a resist film on the wafer 12,
A resist solution is dropped from the nozzle 15 onto the upper surface of the wafer 12 held on the spin chuck 14, then the wafer 12 is rotated, and the resist solution is spread by centrifugal force to apply a resist film. Further, a volatile cleaning solution such as a thinner is sprayed from a cleaning nozzle 17 on a resist film portion formed by the resist solution wrapping around and behind the wafer, thereby dissolving and removing an unnecessary portion of the resist film. .

[0004]

By the way, the applied volatile cleaning liquid is scattered by the centrifugal force due to the rotation of the wafer, adheres to the inside of the spin cup, is vaporized, and deprives the spin cup of heat of vaporization. For this reason, the temperature of the spin cup and the ambient temperature in the spin cup gradually decrease, so that the surface temperature of the wafer decreases. For this reason, the temperature of the dropped resist solution is lowered, the fluidity is reduced, and the spreading method due to the centrifugal force is changed, so that there is a problem that the thickness of the resist film varies within a wafer surface or between wafers. In view of the circumstances as described above, an object of the present invention is to provide a spin coater that applies a resist film so that the thickness of the resist film is uniform within a wafer surface or between wafers.

[0005]

The present inventor tried to prevent the temperature of the atmosphere inside the spin cup from lowering by blowing heated air to the outside of the spin cup, but it was not very effective. Therefore, as a result of intensive studies, the present inventors have focused on heating the spin cup using warm water, and have completed the present invention. In order to achieve the above object, a spin coater according to the present invention holds a wafer on a horizontal holding surface,
A spin coater including a spin chuck that rotates around a vertical rotation axis and a spin cup, wherein the spin cup is formed of a metal plate having good heat conductivity and is provided to surround the periphery of the wafer chuck. Cup body and
A heat transfer tube disposed in close contact with the outer wall of the cup body,
It is characterized in that the cup body is heated by passing the temperature-regulated water from an external temperature-regulated water supply source to the heat transfer tube.

According to the present invention, the atmosphere temperature in the cup is maintained within a predetermined temperature range, and the fluidity of the resist solution does not decrease, so that the film thickness of the resist film becomes uniform within the wafer surface or between wafers. When the cup body is constituted by a double wall plate composed of an inner wall plate and an outer wall plate, and the heat transfer tube is provided between the inner wall plate and the outer wall plate, heat transfer is improved. In this case, if a heat insulating material is provided between the adjacent heat transfer tubes, the atmosphere temperature in the cup can be more easily maintained within a predetermined temperature range. As a preferred embodiment of the present invention, the heat transfer tube is provided with a single tube continuously arranged in a serpentine or coil shape from the inlet to the outlet, or provided between the inlet header and the outlet header. It is formed of a plurality of tubes.

[0007]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. Embodiment This embodiment is an embodiment of a spin coater in which a spin cup is constituted by a double wall plate composed of an inner wall plate and an outer wall plate. FIG. 1 is a side sectional view of the spin coater of the present embodiment. The spin coater 20 of this embodiment includes a spin cup 22 having a configuration different from that of the conventional spin coater 10, and the other components are the same. Therefore, in FIG. 1, the same components as those in FIG. 2 are denoted by the same reference numerals, and the description thereof will be omitted.

The spin cup 22 is connected to the wafer chuck 14.
A cup body 27 having a double wall structure including a stainless steel inner wall plate 24 and an outer wall plate 26 so as to surround the periphery of the
Heat transfer tube 28 disposed between inner wall plate 24 and outer wall plate 26
And The space between the inner wall plate 24 and the outer wall plate 26 is equally spaced over all parts. The bottom surface of the spin cup 22 is slightly inclined so that the resist solution that is scattered during the formation of the resist film and adheres to the inside of the spin cup 22 and drips on the bottom surface is discharged from the drain pipe 18. Heat transfer tube 2
Numeral 8 is continuous with a single pipe from the inlet to the outlet, is disposed in a coil shape at substantially equal intervals, and is in close contact with the inner wall plate 24. A heat insulating material is filled between adjacent heat transfer tubes. Further, the end of the heat transfer tube 28 is provided with a supply source (not shown) for supplying and draining temperature-regulated water and a discharge port (not shown).
And quick couplers 34A and 34B for facilitating attachment and detachment are attached to respective ends.

When a resist film is formed on the wafer 12 using the spin coater 20, the temperature of the spin cup 22 is increased by passing temperature-regulated water through the heat transfer tube 28, so that the ambient temperature in the inner wall plate 24 is reduced to a predetermined temperature. Keep within range. Next, a resist film is applied in the same manner as in the prior art, and a cleaning liquid is sprayed from a cleaning nozzle 17 on the resist film portion formed around the wafer and on the back side to dissolve and remove the same.

In this embodiment, when forming a resist film,
Since the spin cup 22 is heated, the cleaning liquid scatters,
Even if the spin cup 22 is vaporized and the vaporization heat is removed from the spin cup, the temperature of the spin cup 22 is maintained within a predetermined temperature range, and the ambient temperature inside the spin cup 22 is also maintained within a predetermined temperature range. Therefore, since the wafer temperature does not decrease in the process of sequentially coating the wafer with the resist film, the resist film can be formed uniformly in the plane, and the film thickness becomes uniform among the wafers. Also, since the heat transfer tube 28 is not exposed,
Even if the rotating wafer 12 is broken and scattered in the spin cup 24, it does not directly collide with the heat transfer tube 28 and is not damaged. Further, since the inner wall plate 24 is made of stainless steel, it is easy to wash and remove the resist solution that has scattered and adhered to the inner wall plate 24 as in the related art.

[0011]

According to the present invention, the spin cup of the spin coater is provided with the heat transfer tube in close contact with the outer wall of the cup body having good heat conductivity. Even if it adheres to the inside of the cup and evaporates to remove the heat of vaporization from the cup, the temperature of the cup and the atmosphere inside the cup can be reduced by heating the cup by passing temperature-regulated water from outside to the heat transfer tube. It is maintained within a predetermined temperature range. Therefore, in the process of sequentially coating the wafer, the surface temperature of the wafer is maintained within a predetermined temperature range, and the fluidity of the resist solution dropped does not change. Can be made uniform. In addition, a stainless steel spin cup can be used, and the spin cup can be easily cleaned.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a spin coater according to the present embodiment.

FIG. 2 is a side sectional view of a conventional spin coater.

[Explanation of symbols]

10 ... Spin coater, 12 ... Wafer, 14 ... Spin chuck, 15 ... Nozzle, 16 ... Spin cup,
17 cleaning nozzle, 18 drain pipe, 20
... Spin coater, 22 ... Spin cup, 24 ... Inner wall plate, 26 ... Outer wall plate, 27 ... Cup body, 28 ... Heat transfer tube, 30 ... End face part, 32A, B ... Equipment piping, 34
A, B ... Quick coupler.

Claims (3)

[Claims] 1. A spin coater comprising: a spin chuck for holding a wafer on a horizontal holding surface and rotating about a vertical rotation axis; and a spin cup, wherein the spin cup has good heat conductivity. Formed of metal plate,
A cup body provided to surround the periphery of the wafer chuck, and a heat transfer tube provided in close contact with the outer wall of the cup body, and temperature-controlled water is supplied from an external temperature-controlled water supply source to the heat transfer tube. A spin coater characterized by heating the cup body with water. 2. The spin coater according to claim 1, wherein the cup body is constituted by a double wall plate comprising an inner wall plate and an outer wall plate, and the heat transfer tube is provided between the inner wall plate and the outer wall plate. . 3. A heat transfer tube in which one tube is continuously arranged in a serpentine or coil shape from an inlet to an outlet, or a plurality of heat transfer tubes provided between an inlet header and an outlet header. The spin coater according to claim 1, wherein the spin coater is formed of a tubular body.