JPH0566571A - Baking method for resist - Google Patents

Abstract

PURPOSE:To suppress the contamination of a substrate and thermal influence upon a substrate conveyance system as to the baking method for, specially, multi-layered resist. CONSTITUTION:Substrates coated with resist are mounted on hot plates 1 at intervals, which are adjusted to set the temperature raising time of the substrates to a specific value, and one substrate is heated on one hot plate 1. Here, the resist is an intermediate layer consisting of the lower-layer resist and spin-on glass(SOG) of the multi-layered resist. Further, the hot plates 1 are used to heat the substrates in parallel.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist baking method, and more particularly to a multilayer resist baking method.

With the miniaturization of semiconductor devices, it has become difficult to perform patterning in a portion having a large step on a substrate in a photolithography process. Therefore, a multi-layer resist is used to alleviate the step (one of the purposes of adopting the multi-layer resist). Because the lower layer resist bursts,
There was a need for improved baking methods.

[0003]

2. Description of the Related Art FIG. 3 is an explanatory view of baking according to a conventional example. In the figure, 1, 2, 3 are hot plates,
The temperatures are set to a ° C., b ° C., and c ° C. (a <b <c), and the residence time on each hot plate is t seconds.

In this way, the substrate is moved on the plurality of hot plates whose temperature settings are changed by the transfer device so that the substrate temperature is raised stepwise.

[0005]

In the conventional example, since the substrate passes over a plurality of hot plates, dust is easily attached. Further, since the baking is performed in multiple stages, there is a problem in that the heat influence on the transfer robot is increased and the heat is transferred to the substrate in the room temperature state during the transfer.

Therefore, the substrate is apt to be contaminated and the temperature of the substrate cannot be controlled, which causes a problem that the coating film thickness distribution is deteriorated. An object of the present invention is to suppress contamination of a substrate and thermal influence on a substrate transfer system.

[0007]

To solve the above-mentioned problems, 1) a substrate coated with a resist is placed on the hot plate parallel to the surface of the hot plate at a certain distance, and the interval of the certain distance is adjusted. The resist is baked by setting the temperature rise time of the substrate to a predetermined value and heating the substrate with one hot plate per substrate, or 2) the resist is a lower layer resist of a multilayer resist and a spin-on-glass ( SOG), which is an intermediate layer, which is the resist baking method described in 1) above, or 3) The baking method of resist described in 1) or 2) above in which the substrates are heated in parallel using a plurality of hot plates. To be done.

[0008]

1 (A) to 1 (D) are explanatory views of the principle of the present invention.
FIG. 1 (A) shows a normal proximity hot plate, 1 is a hot plate, and 4 is a proximity gap pin for mounting a substrate close to the hot plate.

In this case, since the substrate and the hot plate are close to each other, the substrate temperature rises rapidly as shown in FIG. 1 (B). When the height of the proximity gap pin is increased in Fig. 1 (C), the substrate temperature rises gradually as shown in Fig. 1 (D).

The present invention takes advantage of this fact by adjusting the height of the proximity gap pin in accordance with the desired rising characteristic of the substrate temperature,
Baking is done with one hot plate.

[0011]

EXAMPLE FIGS. 2A and 2B are explanatory views of an example of the present invention. In Fig. 2 (A), hot plates 1, 2 and 3 were processed in parallel, and the residence time of the substrate on each hot plate was set to 3
It is t seconds (for example, t = 60 seconds).

FIG. 2A shows the time course of the substrate temperature on each hot plate in this case. The height of the proximity gap pin 2 is adjusted so as to reach the final temperature c ° C. (for example, 270 ° C.) 2 t seconds after the room temperature, heating at the final temperature is continued for t seconds, and then the substrate is taken out.

In this case, the problem of reduced throughput can be solved by processing the hot plates 1, 2, 3 in parallel. Thus, in the embodiment, one hot plate / substrate can be processed.

[0014]

According to the present invention, since one hot plate / substrate can be used for processing, adhesion of dust on the substrate and thermal influence on the substrate transfer system can be suppressed, which contributes to improvement of the coating film thickness distribution. It was

[Brief description of drawings]

FIG. 1 is an explanatory view of the principle of the present invention.

FIG. 2 is an explanatory diagram of an embodiment of the present invention.

FIG. 3 is an explanatory diagram of baking according to a conventional example.

[Explanation of symbols]

1,2,3 Hot plate 4 Proximity gap pin for placing the substrate close to the hot plate

Claims (3)

[Claims] 1. A substrate coated with a resist is placed on the hot plate parallel to the surface of the hot plate and at a fixed distance, and the interval of the fixed distance is adjusted to set the temperature rising time of the substrate to a predetermined value. Then, the method for baking a resist is characterized in that the substrate is heated by one hot plate per substrate. 2. The resist baking method according to claim 1, wherein the resist is an underlayer resist of a multilayer resist and an intermediate layer made of spin-on-glass (SOG). 3. The method for baking a resist according to claim 1, wherein the substrate is heated in parallel by using a plurality of the hot plates.