KR960000184B1 - Manufacturing method of phase shift mask - Google Patents

Abstract

formulating a phase inversion material pattern on a quartz substrate; formulating the first sensitive film pattern by passivating the first sensitive film on opposite surface of the quartz substrate; formulating the first chrome pattern by eliminating the first sensitive film pattern after depositing the first chrome film on the quartz substrate where the first sensitive film pattern is fabricated; formulating the second sensitive film pattern by passivating the second sensitive film pattern; baking the second sensitive film pattern after eliminating the first chrome pattern; formulating the third sensitive film pattern by etching back the parts after passivating the third sensitive film; formulating the second chrome film by eliminating the second sensitive film pattern, remaining the third sensitive film after passivating the second chrome film.

Description

Method for manufacturing automatic batch phase shift mask

1A is a cross-sectional view of a conventional rim type phase inversion mask.

Figure 1b is a conventional improved phase inversion mask.

2a to 2l is a cross-sectional view of the automatic batch type phase inversion mask manufacturing process according to the present invention.

* Explanation of symbols for main parts of the drawings

1: quartz substrate 2: chromium film

3: phase inversion material film 4: first photosensitive film

4 ′: First photosensitive film pattern 5: Front exposure

6: first chrome film 6 ′: first chrome pattern

7: second photosensitive film 8: back exposure

9: second photosensitive film pattern 10: third photosensitive film

11: remaining third photosensitive film 12: second chrome film

13: second chrome pattern

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a phase shift mask used in a photolithography process in a semiconductor manufacturing process, and more particularly, to a method of manufacturing an auto-positioned phase shift mask for automatically aligning a chrome film.

The photolithography process in the semiconductor manufacturing process is a technique of transferring a predetermined pattern onto a wafer using a mask and an exposure machine. The use of a phase reversal mask provides a better resolution than the currently used mask and exposure technique. It is possible to form an ultrafine pattern according to the high integration.

Phase inversion mask technology has been developed in various forms and has good characteristics, but each has its disadvantages.

FIG. 1A is a rim type phase inversion mask, which is a kind of phase inversion mask, which deposits chromium on a quartz substrate 1, forms a phase inversion material pattern 3 on chromium, and wets the chromium. An under cut chromium film 2 is formed.

However, since it is very difficult to control the degree of uncut of the chromium film, the chromium pattern 2 is formed on the phase shift material pattern 3 as shown in FIG. 1b. I couldn't align it exactly.

Accordingly, an object of the present invention is to provide an automatic batch type phase inversion mask manufacturing method that can be applied to an ultra-high density device by automatically placing a chromium film on a phase inversion material.

In order to achieve the above object, the present invention provides a first step of forming a phase inversion material pattern on a quartz substrate, and applying a first photosensitive film to a surface opposite to the quartz substrate on which the phase inversion material pattern is formed, and forming the phase inversion material pattern. A second step of forming a first photoresist pattern by exposing and developing the first photoresist pattern, depositing a first chromium film on the quartz substrate on which the first photoresist pattern is formed, and then removing the first photoresist pattern to form a first chromium pattern. The third step, the fourth step of forming a second photosensitive film pattern by applying a second photosensitive film on the entire surface of the quartz substrate on which the phase inversion material pattern is formed and exposing and developing the side on which the phase inversion material pattern is formed. A fifth step of baking the second photoresist layer pattern after removing the pattern; a third surface of the quartz substrate on which the phase shift material pattern and the second photoresist pattern are formed; A sixth step of forming a residual third photoresist film by etching back part of the photoresist film, applying a second chromium on top of the entire quartz substrate structure on which the phase inversion material pattern is formed; And a seventh step of forming the second chromium film by removing the remaining third photoresist film.

Hereinafter, the present invention will be described in detail with reference to the attached drawings 2A to 2L.

2A to 2L show cross-sectional views of an automatic batch type phase inversion mask manufacturing process according to the present invention.

First, the phase inversion material film 3 is coated on the quartz substrate 1 as shown in FIG. 2A, and then the phase inversion material pattern 3 is coated using the electron beam. 3 '), a positive type first photosensitive film 4 is applied to the back surface of the quartz substrate 1 as shown in FIG. 2C, and then exposed to the front surface 5 and developed as shown in FIG. 2D. The photosensitive film pattern 4 'is formed.

Subsequently, a first chromium film 6 is deposited on the back surface of the quartz substrate 1 on which the first photoresist pattern 4 'is formed as shown in FIG. 2e, and the first photoresist pattern 4' is removed as shown in FIG. 2f. To form a first chrome pattern 6 ', and apply a negative type second photosensitive film 7 to the entire surface of the quartz substrate 1 on which the phase inversion material pattern 3' is formed as shown in FIG. After forming the second photoresist layer pattern 9 as shown in FIG. 2F by the rear light guide 8, the first chromium pattern 6 ′ is removed and a bake process is performed to bake the photoresist layer at a temperature of 110 to 160 ° C. do.

In this case, the second photoresist layer pattern 9 serves as an auto-layout layer that allows the chromium layer deposited later to be accurately aligned.

Subsequently, a third photosensitive film 10 is coated on the entire surface of the quartz substrate 1 on which the phase inversion material pattern 3 'and the second photosensitive film pattern 9 are formed, as shown in FIG. 2i, and as shown in FIG. A portion of the photoresist film 10 is etched back to form the remaining third photoresist film 11, and the second chromium film 12 is deposited on the entire structure of the entire surface of the quartz substrate 1 as shown in FIG. 2K.

Finally, when the second photoresist layer pattern 9 and the remaining third photoresist layer 11 are removed as illustrated in FIG. 2L, the second chromium pattern 13 may be automatically aligned.

If the first photoresist film is used as the negative photoresist film and the second photoresist film is used as the positive photoresist during the process step, only the position of the first chrome pattern formed on the back of the quartz substrate is changed, but the shape of the process and the final mask are the same. .

The phase shift mask according to the present invention provides an mask in which the phase shift material of the lower layer and the chromium pattern of the upper layer are precisely aligned, thereby improving the ultra-high integration of the semiconductor device and the reliability of the device.

Claims (2)

In the method of manufacturing a phase inversion mask, a first step of forming a phase inversion material pattern 3 'on a quartz substrate 1 is performed on a surface opposite to the quartz substrate 1 in which the phase inversion material pattern 3' is formed. The second step of forming the first photoresist pattern 4 'by coating the first photoresist layer 4 and developing the first photoresist layer pattern 4' by applying the photoresist layer 4 to the front surface 5 and developing the phase inversion material pattern 3 '. A third step of forming the first chrome pattern 6 'by depositing the first chromium film 6 on the quartz substrate 1 on which the 4' is formed, and then removing the first photoresist pattern 4 '. The second photoresist film 7 is coated on the entire surface of the quartz substrate 1 on which the phase shift material pattern 3 'is formed, and the second photoresist film is formed by the back exposure 8 and the side on which the phase shift material pattern 3' is formed. A fourth step of forming the pattern 9, a fifth step of baking the second photoresist pattern 9 after removing the first chrome pattern 6 ′, and the phase inversion The third photoresist film 10 is applied to the entire surface of the quartz substrate 1 on which the patterns 3 'and the second photoresist pattern 9 are formed, and then a part of the third photoresist film 11 is etched back to form the remaining third photoresist film 11. In step 6, after the second chromium film 12 is coated on the entire structure of the quartz substrate 1 on the side of the phase inversion material pattern 3 ′, the second photoresist layer pattern 9 and the remaining third photoresist layer ( And 11) removing the second chromium film pattern (13) to form the second chromium film pattern (13). Method according to claim 1, characterized in that the first and second photosensitive films (4, 7) are respectively negative, positive or positive and negative respectively.