JPH0744142B2 - Method for removing scattered photoresist - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for removing photoresist scattered matter scattered on the inner surface of a container when applying a photoresist.

[Conventional technology]

A spin coating method is known as a method for applying a photoresist onto a wafer. This method uses a spin coater,
This is a method of forming a uniform photoresist film on a wafer by dropping a photoresist on the wafer and rotating the wafer. Since this method rotates the wafer to apply the photoresist, a large amount of the photoresist solution is scattered on the inner surface of the spin cup when applying the photoresist, and thus the accuracy of forming the photoresist film is deteriorated. .

For this reason, it is necessary to wash the inner surface of the spin cup by constantly removing the photoresist scattered material scattered on the inner surface of the spin cup when applying the photoresist.

FIG. 2 is a spin coater sectional view showing a conventional method of removing scattered photoresist. As shown in the figure, a rinse liquid 2 which is an organic solvent capable of dissolving the photoresist scattered substances is flown on the inner surface of the spin cup 1 and the wafer chuck 3 is rotated to rinse out the photoresist scattered substances 5 scattered from the wafer 4. It is dissolved in liquid 2. Then, the rinse solution 2 in which the scattered photoresist material 5 is dissolved is poured out from the rinse solution discharge port 6 to remove the scattered photoresist material 5. Further, the rinse liquid 2 softens the impact of the mist-like photoresist scattered matter 5 when it collides with the inner surface of the spin cup 1, and the photoresist scattered matter 5 becomes the spin cup 1.
Bounce from the inner surface of the wafer 4
It also serves to prevent the occurrence of defects on the top. In addition, 8 is an exhaust port.

[Problems to be Solved by the Invention]

The conventional method of removing scattered photoresist is performed as described above, and since it is necessary to constantly flow the rinse liquid onto the inner surface of the spin cup during the photoresist application, there is a problem that a large amount of rinse liquid is required. It was

In addition, since the vapor pressure of the rinse liquid affects the film thickness of the photoresist formed on the wafer and its in-plane uniformity, the flow rate of the rinse liquid, the timing of the rinse liquid, the exhaust from the exhaust port 8 and the like are subtle. However, there is a problem in that it requires complicated adjustment and the operation is complicated.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a method for removing photoresist scattered particles which is easy to operate without lowering the photoresist forming accuracy.

[Means for Solving the Problems]

The method of removing scattered photoresists according to the present invention is
Before the photoresist coating process of coating the photoresist on the wafer in the container, a layer is formed on the inner surface of the container with a material that is insoluble and adsorbable to the scattered material of the photoresist and that is easily peeled from the inner surface of the container. And a step of removing the photoresist scattered material by peeling the layer, to which the photoresist scattered material scattered during the photoresist coating step is attached, from the storage cup after the photoresist coating step. I'm out.

[Action]

In the present invention, since the photoresist scattered matter is removed by peeling off the layer, the photoresist scattered matter can be easily removed without affecting the photoresist coating process.

〔Example〕

FIG. 1 is a cross-sectional view of a spin coater showing a method for removing photoresist scattered particles which is an embodiment of the present invention. As shown in the figure, before the photoresist coating process, a urethane resin, which is an organic polymer insoluble in the photoresist solution, is dissolved in alcohol and coated, and dried to form a polymer film 9 on the entire inner surface of the spin cup 1. is doing. 3-5
The description is omitted because it is the same as the conventional one.

Since the polymer film 9 is formed on the inner surface of the spin cup 1, all the photoresist scattered material 5 scattered during the photoresist coating process adheres to the polymer film 9 as shown in FIG.
Since the polymer film 9 has an adsorbing power to the photoresist scattered material 5, it is possible to prevent the photoresist scattered material 5 from being repelled from the polymer film 9 and attached to the wafer 4 already coated with the photoresist.

Then, the photoresist scattered matter 5 is, to some extent, the polymer film 9
If it adheres to the top, the polymer film 9 is peeled off, so that the photoresist scattered matter 5 adhered to the polymer film 9 can be removed at the same time, and the spin cup 1 can be easily washed.

Thus, since the photoresist scattered material 5 can be removed by peeling off the polymer film 9, unlike the conventional method in which the photoresist scattered material 5 is removed by the rinse liquid during the photoresist application, there is no difference in the photoresist forming accuracy. No adverse effect. That is, the film thickness of the photoresist and its uniformity can be accurately maintained without the need for complicated operations such as adjusting the flow rate of the rinse liquid at the time of applying the photoresist as in the conventional case, and the operation is easy. is there.

Further, since it is not necessary to flow the rinse liquid, it is not necessary to provide the rinse liquid discharge port and the exhaust port in the spin cup 1 as in the conventional case, and the structure of the spin cup 1 can be simplified.

In addition, in this embodiment, the photoresist coating method by the spin coating method is given as an example, but other photoresist coating methods may also be used as long as the photoresist scattered matter is generated during photoresist coating. This invention can be applied.

In this embodiment, the polymer film 9 is formed on the inner surface of the spin cup 1. However, the material is insoluble and adsorbable to the photoresist scattered material 5, and is easily peeled from the inner surface of the spin cup 1. It can be used instead.

〔The invention's effect〕

As described above, according to the present invention, since the photoresist scattered matter is removed by peeling the layer, there is an effect that the photoresist scattered matter removal operation can be easily performed without lowering the photoresist forming accuracy.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a method for removing a photoresist scattered material according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view showing a conventional method for removing a photoresist scattered material. In the figure, 1 is a spin cup, 4 is a wafer, 5 is photoresist scattered material, and 9 is a polymer film. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] 1. Before the photoresist coating process of coating a photoresist on a wafer in a container, the inside surface of the container is insoluble and adsorbable to the scattered material of the photoresist, and easily peeled from the inside surface of the container. A step of forming a layer made of a material, and after the photoresist coating step, the photoresist scattering material is removed by peeling the layer to which the photoresist scattering material scattered during the photoresist coating step adheres from the container. A method for removing photoresist scattered matter, including the steps of :.