KR19990024798A - Exposure Method of Semiconductor Device Using VSB Method - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a semiconductor device, and more particularly, to a semiconductor device using a VSB method that can quickly and easily form an arbitrary pattern on a semiconductor substrate coated with a photosensitive film during an exposure process using an electron beam. It relates to an exposure method.

According to the present invention, in order to form an arbitrary pattern on a semiconductor substrate coated with a photoresist film, at least one of the cell masks included in the exposure apparatus is rotated to form a polygon, for example, a triangular pattern instead of a rectangle. do. Accordingly, the switching time and the overall exposure time can be shortened when the graphic data of the arbitrary patterns are converted into data suitable for the exposure apparatus, and various arbitrary patterns of various forms can be formed.

Description

Exposure Method of Semiconductor Device Using VSB Method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a semiconductor device, and more particularly, to an exposure method of a semiconductor device using a VSB method that can quickly and easily expose an arbitrary pattern on a semiconductor substrate coated with a photosensitive film.

In accordance with the trend toward higher integration of semiconductor devices, the widths of the patterns formed on the substrate and the gaps between them are also miniaturized, and accordingly, the exposure technique for forming the patterns is also variously changed.

In particular, recently, an electron-beam lithography technique has been implemented as one of the exposure techniques, and the exposure technique using the electron beam is essential for the development of next-generation devices. However, the exposure technique using the electron beam has a big disadvantage of low throughput per unit time, although the resolution and accuracy are superior to other exposure techniques. There is a situation.

Exposure techniques using electron beams include Gaussian beam method, Variable Shaped Beam (VSB) method, and Cell Projection method depending on the beam shape, and cell projection method in terms of throughput per unit time. This is the best, followed by VSB and Gaussian. In a substantial semiconductor device manufacturing process, a cell scanning method is mainly used for a cell region with many repeated patterns, and a VSB method is used for a cell peripheral region with many unique patterns.

In the above description, in the VSB method, the first cell mask 1 and the second cell mask 2 each having the same shape, for example, a quadrangular mask pattern, are provided with their mask patterns. In the state where they are made to overlap a predetermined part, it is a method of forming the square pattern 3 on the board | substrate to which the photosensitive film was apply | coated by transmitting an electron beam through the overlapping gap of mask patterns. In this VSB method, the graphic data of the pattern to be exposed is divided into several shots, each of which is a single exposure unit, and converted into data suitable for an electron beam exposure apparatus. The converted data is applied to a semiconductor substrate coated with a photoresist film. The pattern of the desired shape is formed in the.

However, since the exposure method of the semiconductor device using the conventional VSB method as described above has a rectangular shape obtained by overlapping cell masks, in order to convert graphic data in a triangular form into data suitable for an electron beam exposure apparatus, it is shown in FIG. As described above, since the graphic data 4 in the form of triangles need to be divided into a myriad of rectangular patterns 3, that is, shots, the time required for data conversion becomes very long. There is a problem in that it is necessary to have a computer having a large storage capacity in order to divide the shot.

In addition, since the actual exposure time is proportional to the number of shots, there is a problem that the overall exposure time becomes longer due to the increase in the number of shots.

Accordingly, the present invention has been made in order to solve the above problems, various shapes that can be obtained by overlapping the two cell masks by rotating at least one of the two cell masks each provided with a mask pattern. Accordingly, the present invention provides a method of exposing a semiconductor device using a VSB method that can divide graphic data of an arbitrary pattern into smaller shots, reduce data switching time and shots, and shorten exposure time. There is this.

1 is a view for explaining an exposure method using a conventional VSB method.

2 is a diagram for explaining a method of dividing graphic data applied to a conventional VSB method.

3 is a view for explaining an exposure method of a semiconductor device using a VSB method according to an embodiment of the present invention.

4 is a diagram for explaining a method of dividing graphic data applied to the present invention.

5 is a view for explaining another embodiment of the present invention.

Explanation of symbols for main parts of the drawings

11: first cell mask 2,31: second cell mask

13,22: triangle shaped pattern 21: square shaped pattern

32: rhombus mask pattern

The above object is to apply a photosensitive film by transmitting an electron beam through a gap between overlapping mask patterns while first and second cell masks each having a rectangular mask pattern provided therein to overlap a predetermined portion of the mask patterns. A method of exposing a semiconductor device using a VSB method of forming an arbitrary pattern on a semiconductor substrate, wherein the pattern is formed by rotating at least one of the first and second cell masks. It is achieved by the exposure method of a semiconductor device using the VSB method according to the invention.

According to the present invention, since the first or second cell mask is rotatable, the shape of the pattern obtained by overlapping the mask patterns provided in the first and second cell masks, respectively, may vary. The number of shots can be significantly reduced at the time of converting the graphic data of the arbitrary angle patterns into data suitable for the electron beam exposure apparatus.

EXAMPLE

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

3 is a view for explaining a semiconductor device exposure method using a VSB method according to an embodiment of the present invention, the first or second cell mask (11, 12), preferably, the second installed in the exposure apparatus In a state where the cell mask 12 is rotatably provided, the second cell mask 12 is rotated by a predetermined angle to form an arbitrary pattern on the semiconductor substrate to which the photosensitive film is applied.

Here, in the exposure process using the VSB method, in order to form an arbitrary pattern on the semiconductor substrate to which the photoresist film is applied, the mask patterns provided in the same shape inside the first and second cell masks 11 and 12 are respectively provided. The electron beam is transmitted through the overlapped gap. In the present invention, since the second cell mask 12 is rotated and exposed, the mask pattern provided in the first cell mask 11 and the mask pattern provided in the second cell mask 12 are exposed. In the case of overlapping, a pattern 13 having a polygonal shape, for example, a triangular shape, may be formed.

4 is a diagram illustrating a pattern dividing method for converting graphic data of an arbitrary pattern according to the present invention into data suitable for an exposure apparatus. As shown in FIG. 4, an arbitrary angle pattern, for example, a triangle-shaped pattern as a whole is illustrated. The pattern 21 is divided into a quadrangular pattern 21 and a triangular pattern 22. Here, the square pattern 21 is obtained by the same method as the conventional method, and the triangular pattern 22 is rotated by a predetermined angle of the second cell mask in accordance with the present invention after making the overlapped form of the mask pattern into a triangular shape It can obtain by performing an exposure process.

Therefore, in the present invention, since the triangular graphic data is divided into a rectangular pattern and a triangular pattern during exposure of the semiconductor device using the VSB method, the graphic data of arbitrary patterns is converted into data suitable for the electron beam exposure apparatus. The switching time can be shortened at the time, and when a graphic data is to be converted into data suitable for an exposure apparatus, a large amount of data is not necessary because the amount of the data is small.

In addition, since the number of shots as a single exposure unit can also be significantly reduced in comparison with the conventional case, the overall exposure time can be shortened.

In addition, as shown in FIG. 5, by providing a rhombus mask pattern 32 in the second cell mask 31, an arbitrary angle pattern having various angles may be realized, and likewise, in the first cell mask The same effect can be obtained also if a rhombus mask pattern is provided.

As described above, the present invention can shorten the data conversion time by providing the second cell mask rotatably, and shorten the overall exposure time by reducing the number of shots. Accordingly, the throughput per unit time can be improved when the electron beam exposure is fixed using the VSB method, and an arbitrary angle pattern having more various angles can be accurately realized.

Meanwhile, although specific embodiments of the present invention have been described and illustrated, modifications and variations can be made by those skilled in the art. Accordingly, the following claims are to be understood as including all modifications and variations as long as they fall within the true spirit and scope of the present invention.

Claims (5)

The first and second cell masks, each having a rectangular mask pattern therein, are formed so that their mask patterns overlap with each other, and the electron beams are transmitted through the gaps of the overlapping mask patterns to be applied to the photosensitive film. In the exposure method of the semiconductor element using the VSB system which forms each pattern, And at least one of the first and second cell masks is rotated to form an arbitrary pattern. The semiconductor device exposure method of claim 1, wherein the first cell mask is rotated to form an arbitrary pattern. The semiconductor device exposure method of claim 1, wherein the second cell mask is rotated to form an arbitrary pattern. The method of claim 1, wherein the mask pattern provided in the first cell mask has a rhombus shape. The method of claim 1, wherein the mask pattern provided in the second cell mask has a rhombus shape.