KR100800782B1 - Method for fabricating a resist pattern mask - Google Patents

Abstract

A method for fabricating a mask is provided to simplify a fabricating process and form a non-deformed light preventing pattern by forming a light preventing pattern by an exposure and development process. Photoresist with increased light absorption is coated on a substrate(11) to form a photoresist layer. The photoresist layer is selectively exposed and developed to form a light preventing pattern(17). The photoresist can include a photosensitive material that absorbs the light caused by the exposure process. The light preventing pattern can be heat-hardened.

Description

METHOD FOR FABRICATING A RESIST PATTERN MASK

FIGS. 1A and 1B are process drawings showing a mask manufacturing method according to the related art.

2A and 2B are process drawings showing a method of manufacturing a mask according to the present invention.

Description of the Related Art [0002]

21: quartz substrate 23: photosensitive film

25: Shading pattern

The present invention relates to a method of manufacturing a resist pattern mask used during an exposure process in semiconductor manufacturing.

In an exposure process in a semiconductor manufacturing process, light is irradiated onto a mask having the same or a phase-inverted pattern as a pattern to be formed on a semiconductor chip, and the photosensitive film coated on the wafer is exposed to the light. It is one.

The mask used in this exposure process is made of quartz or glass, and the same circuit wiring as the pattern to be formed on the chip of the wafer is formed on the surface. At this time, the mask is made in a state in which a chromium film is deposited on a disk made of quartz or glass.

1A to 1B are process drawings showing a mask manufacturing method according to the prior art.

As shown in FIG. 1A, chromium (Cr) is deposited on a quartz substrate 11 to form a cornea 13. Then, a photoresist is coated on the cornea 13, and exposed and developed to form a photoresist pattern 15.

Then, as shown in FIG. 1B, the exposed portion of the cornea 13 is selectively etched using the photoresist pattern 15 as a mask to form a light-shielding pattern 17. [ Then, the photoresist pattern 15 is stripped and removed.

As described above, in the prior art, a photoresist pattern is formed on a chromium thin film as a corneal epithelium, and the corneal epithelium is selectively etched using the photoresist pattern as a mask so as to leave a shielding pattern.

However, when etching the corneal cornea using the photoresist pattern as a mask, etching rate difference is partially generated depending on the inevitable pattern size, density, and position due to the characteristics of the etching process, and a part of the photoresist pattern is etched together. Accordingly, since the part of the cornea that is not to be etched is etched, the light-shielding pattern is formed in a different deformed pattern without forming a desired pattern.

Therefore, when the mask having such a modified light-shielding pattern is used in the exposure process, there is a problem that the characteristics of the semiconductor chip are adversely affected. In addition, the mask manufacturing method according to the related art has a problem in that the manufacturing process is complicated and the manufacturing cost is high because the corneal epithelium must be selectively etched.

Therefore, an object of the present invention is to provide a method of producing a resist pattern mask having an accurate light-shielding pattern without modification.

It is another object of the present invention to provide a method of manufacturing a resist pattern mask which is simple in manufacturing process and low in manufacturing cost.

According to another aspect of the present invention, there is provided a method of manufacturing a mask, the method comprising: forming a photoresist by applying a photoresist with a photoresist on a quartz substrate to increase light absorption; And forming a light-shielding pattern by developing.

Further, the method of the present invention further includes a step of thermally curing the light-shielding pattern.

Hereinafter, a method of manufacturing a mask for a resist pattern according to the present invention will be described in detail with reference to the accompanying drawings.

Referring to Figs. 2A and 2B, a process drawing showing a method of manufacturing a mask according to a preferred embodiment of the present invention is shown.

First, as shown in FIG. 2A, a photoresist film 23 is formed by preparing a substrate 21, and then applying photoresist by a predetermined thickness on the substrate 21. At this time, the substrate 21 includes transparent quartz or glass. Further, according to the present invention, the photoresist is directly applied onto the substrate 21 without depositing a chromium film. The photoresist used in this case must act as a chromium film for shielding the light used in the semiconductor exposure process in the conventional resist pattern mask, so that the light absorption for light must be high. To this end, the photoresist of the present invention uses a photoresist to which a light-absorbing photosensitive material is added. The thickness of the photoresist applied on the substrate 21 should be such as to maximize the light absorption for wafer exposure light and the resolution at the time of mask pattern formation, It is preferable that the thickness is as large as possible and higher than the light absorption coefficient. Therefore, the thickness of the photoresist is preferably 1 占 퐉 or less, and more preferably 0.3 占 퐉 to 2.5 占 퐉.

Then, the photoresist film 23 is selectively exposed and developed by a laser beam or an electron beam. Through such exposure and development processes, a mask for a resist pattern having a predetermined pattern is formed as shown in Fig. 2B. The mask for a resist pattern has a light shielding pattern 25 that is not removed from the photoresist film 23 by the exposure and development processes and remains. Therefore, the mask for a resist pattern having the light-shielding pattern 25 manufactured through the above-described process does not cause deformation due to the conventional etching.

Therefore, according to the present invention, by performing the etching process as in the prior art, the resist pattern characteristic on the substrate is not directly transferred to the chromium pattern on the substrate, but the light shielding pattern 23 is formed only through the exposure and development process 25). As a result, it is possible to fundamentally remove the pattern error generated from the etching process during the pattern formation error that deviates from the design of the resist pattern originally, and it is possible to obtain a mask pattern more close to the original design of the resist pattern. In addition, since the etching process is not performed in the manufacturing process of the mask for a resist pattern, the number of the whole manufacturing process can be reduced, and the cost reduction effect can be expected.

Then, in order to increase the strength and lifetime of the shielding pattern 25, the shielding pattern 25 is thermally cured. At this time, the thermal curing to be performed is preferably performed at a temperature lower than the glass transition temperature of the photoresist forming the photoresist layer 23, for example, 50 to 200 ° C.

As described above, the mask of the present invention is a simple process for exposing and developing a photoresist film formed of a photoresist to which a photosensitive material is added on a transparent glass or quartz substrate and having increased light absorption for light used in a semiconductor exposure process Thereby forming a light shielding pattern. In addition, the light-shielding pattern may be thermally cured to increase the strength and lifetime.

Therefore, the present invention is advantageous in that a light-shielding pattern is formed by an exposure and a development process, a manufacturing process is simple, a manufacturing cost is low, and a light-shielding pattern is formed without deforming and with an accurate pattern.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Will be apparent to those of ordinary skill in the art.

Claims (6)

A step of forming a photoresist film by applying a photoresist having increased light absorption on a substrate, And selectively exposing and developing the photoresist film to form a light shielding pattern. The method according to claim 1, Wherein the photoresist contains a photosensitive material that absorbs light by the exposure. The method according to claim 1, Wherein the photoresist is formed to a thickness of 0.3 mu m to 2.5 mu m. The method according to claim 1, Further comprising the step of thermally curing the shielding pattern. The method of claim 4, Shielding pattern is thermally cured to a temperature lower than a glass transition temperature of the photoresist. The method of claim 4, Wherein the thermosetting is performed at a temperature of 50 ° C to 200 ° C.

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