JPH0661135A - Developing method for photoresist film - Google Patents

Abstract

PURPOSE:To enable a photoresist pattern to be formed in excellent reproducibility by a method wherein the with-time decline in the developer concentration during the developing step of a photoresist is to be compensated for avoiding the residual photoresist film and scumming phenomenon. CONSTITUTION:Within the developing method of phtoresist film, the initial developer dripping step (c) is started for five seconds and then the secondary developer dripping step (c) is resumed for five seconds after the lapse of ten seconds since the developing step reaches the wafer interface so as to compensate the developer concentration. Resultantly, the decline in the soldability of a photoresist due to insufficient concentration can be avoided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention uses a developing solution after exposing a photoresist film formed on a semiconductor substrate (hereinafter referred to as a wafer) through a mask or reticle on which a desired semiconductor integrated circuit pattern is drawn. The present invention relates to a developing method for developing a photoresist film.

[0002]

2. Description of the Related Art Conventionally, in this type of photoresist film developing method, a wafer coated with a photoresist film and exposed as shown in the sequence diagram of FIG. 5 is placed on a spinner and rotated to drop a developing solution. The solution is poured into a puddle, and then the developing solution is allowed to stand for about 60 seconds without any particular operation of the developing solution concentration. After that, the rotation speed is increased to perform a pure water rinse treatment and a shake-off drying to perform a desired development treatment. I am giving it. The graph of FIG. 6 shows the change over time in the concentration of the developer until the end of the developing time.

[0003]

When a photoresist film is developed by using the above-mentioned conventional photoresist film developing method, the developing solution on the photoresist film reacts with the developed photoresist film. However, the developer concentration decreases as the developing time progresses as shown in the graph of FIG. Therefore, when the development progresses through the photoresist film to the wafer interface, the solubility of the photoresist is lowered due to the insufficient concentration of the developing solution, and the photoresist film remains and scum is liable to occur. As a result, the shape of the photoresist pattern obtained by exposing and developing the photoresist film through a mask or reticle on which a semiconductor integrated circuit pattern is drawn deteriorates.

Particularly for the formation of a fine pattern, the deterioration of the shape of the photoresist pattern due to such residual photoresist film or scum is fatal.

[0005]

The photoresist film developing method of the present invention is a method of dropping a developing solution onto a wafer on a spinner a plurality of times when developing a photoresist film. Therefore, it is possible to compensate for the concentration of the developing solution that decreases as the developing time progresses, so that when the developing proceeds to the wafer interface, the solubility of the photoresist does not decrease due to the insufficient concentration of the developing solution.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, the present invention will be described with reference to the drawings. FIG. 1 is a sequence diagram of a photoresist film developing method according to the first embodiment of the present invention. At the start of development on the wafer on the spinner, the first development droplet is dropped for 5 seconds to start development, and 10 seconds after development almost reaches the wafer interface through the photoresist film, the second development droplet is dropped for 5 seconds. As shown in the graph of No. 3, the developer concentration is compensated.

When the photoresist film on the wafer is developed by the above method, the solubility of the photoresist does not decrease due to insufficient developer concentration when the development proceeds to the wafer interface, and the photoresist film remains The occurrence of scum can be prevented. As a result, the shape of the photoresist pattern obtained by exposing and developing the photoresist film through the mask or reticle on which the semiconductor integrated circuit pattern is drawn is not deteriorated and is kept in a good state.

FIG. 2 is a sequence diagram of a photoresist film developing method according to the second embodiment of the present invention. At the start of development, the first development droplet is dropped for 5 seconds to start development, and then the second development droplet is dropped for 5 seconds to complete the development solution concentration for 10 seconds when development almost reaches the wafer interface. After 60 seconds from the above, the developing solution concentration is compensated again by performing the third development liquid drop for 2 seconds. The change over time in the development density at that time is shown in the graph of FIG.

In the case of the present embodiment, it is possible to prevent the residual photoresist film and the generation of scum as compared with the first embodiment, and the photoresist pattern shape is not deteriorated.

[0010]

As described above, the method of developing a photoresist film according to the present invention is a method of dropping a developing solution onto a wafer a plurality of times, so that the concentration of the developing solution which decreases as the developing time progresses is compensated. be able to. Therefore, when the development progresses to the wafer interface, the solubility of the photoresist does not decrease due to the insufficient developer concentration, and it is possible to prevent the occurrence of residual photoresist film and scum. As a result, the shape of the photoresist pattern obtained by exposing and developing the photoresist film through a mask or reticle on which a semiconductor integrated circuit pattern is drawn is not deteriorated and is maintained in a good state.

In particular, the effect is great for forming a fine pattern, and it is possible to prevent deterioration of the shape of the photoresist pattern, deterioration of resolution, and deterioration of dimensional uniformity of the photoresist pattern, and it is possible to form the photoresist pattern with good reproducibility. it can.

[Brief description of drawings]

FIG. 1 is a sequence diagram of a photoresist film developing method according to a first embodiment of the present invention.

FIG. 2 is a sequence diagram of a photoresist film developing method according to a second embodiment of the present invention.

FIG. 3 is a graph showing the time dependence of developer concentration in Example 1 of the present invention.

FIG. 4 is a graph showing the time dependence of developer concentration in Example 2 of the present invention.

FIG. 5 is a sequence diagram of a conventional photoresist film developing method.

FIG. 6 is a graph showing a conventional developer concentration time dependency.

Claims (1)

[Claims] 1. A method for developing a photoresist film, which comprises exposing a semiconductor substrate on which a photoresist film is formed through a mask or reticle on which a desired semiconductor integrated circuit pattern is drawn, and then developing with a developing solution. A method for developing a photoresist film, which comprises compensating for a developer concentration at least once and developing.