JPH05114551A - Method for producing exposing pattern - Google Patents

Abstract

PURPOSE:To provide an exposing pattern producing method by which a precise pattern can be plotted with high accuracy. CONSTITUTION:This exposing pattern producing method is constituted in such a way that, when an exposing pattern is produced by equally dividing a plotting pattern composed of a combination of prescribed rectangular and nonrectangular areas into prescribed rectangular patterns on the basis of the shapes of the rectangular areas, the plotting starting points of rectangular patterns corresponding to the nonrectangular areas are shifted in prescribed directions to positions where the rectangular patterns do not receive any proximity effect from adjacent patterns.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an exposure pattern generation method, and more particularly to an exposure pattern generation method for generating a highly accurate exposure pattern suitable for use in the field of pattern exposure with a charged particle beam. In recent years, for example, LS
A large number of exposure apparatuses have been developed for exposing a wafer of a large-scale semiconductor integrated circuit having a high integration density such as I (Large Scale Integrated circuit) through a transmission mask to expose predetermined pattern data with an electron beam or the like.

In such an LSI, as the degree of integration increases, the pattern size of the device becomes smaller, and at the same time, the positional accuracy of the pattern is required to be very high.

[0003]

2. Description of the Related Art As a conventional exposure pattern generating method of this kind, there is, for example, a method shown in FIG. 2 which shows a procedure of electron beam exposure processing. With this exposure pattern generation method,
For example, design data from a design device 1 such as a CAD (Computer Aided Design) system is converted into electron beam drawing pattern data by a conversion processing device 2 and input to an electron beam drawing device 3 which is an exposure device. This is the design device 1
This is because the data formats of the electron beam drawing device 3 and the electron beam drawing device 3 are different. Then, when data conversion is performed by the conversion processing device 2, graphic processing such as layer composition, enlargement / reduction, inversion processing, proximity effect correction processing, and the like are performed.

The electron beam drawing pattern data thus formed is generally rectangular pattern and non-rectangular pattern (triangle,
Parallelogram). That is, for example, when the design device 1 outputs design data as shown in FIG. 3A, the conversion processing device 2 converts the design data into electron beam drawing pattern data as shown in FIG. 3B. .. In the figure, A = D and B = C.

The electron beam drawing apparatus 3 reads the starting points, shapes and sizes of the above-mentioned rectangular pattern and non-rectangular pattern from the electron beam drawing pattern data, and as shown in FIG. Drawing is performed by equally dividing into. Here, the areas indicated by A and B in FIG. 3B, which are non-rectangular patterns, are
For example, when drawing is performed by dividing into a strip shape with the lower left corner of the rectangle as the drawing start point, and the division rule of the non-rectangular pattern is usually smaller than the division rule of the rectangular pattern (for example, 0.1 μm), Position accuracy is guaranteed.

[0006]

However, such a conventional exposure pattern generation method has the following problems. That is, as shown in FIG. 3B, the electron beam drawing pattern data input to the electron beam drawing apparatus 3 is a clean pattern with good symmetry, but as shown in FIG. The symmetry is broken when the exposure shot is performed by dividing the non-rectangular pattern into strips with a predetermined drawing start point as a reference.

When the symmetry is broken, the final pattern at the time of electron beam exposure becomes, for example, as shown by the broken line portion in FIG.
In FIG. 4, even if there is no problem in the pattern shape in the E portion, a portion between the patterns closest to each other, that is, an unnecessary protruding portion in the F portion due to the proximity effect occurs, and the position accuracy is deteriorated. Further, if the minimum required wiring interval at the time of design is L ₁ in the E section, L ₁ > L _{2 in the} F section,
It is also conceivable that an unexpected trouble such as a pattern failure such as a resist bridge may occur at the time of transferring the mask pattern.

This is because the division rule is 0.05 μm, 0.
It has been found that even if the thickness is as small as 03 μm, the improvement is not so great, and the exposure time is rather increased, which is not preferable. [Object] Therefore, an object of the present invention is to provide an exposure pattern generation method for drawing a fine pattern with high accuracy.

[0009]

In order to achieve the above object, an exposure pattern generating method according to the present invention defines a drawing pattern consisting of a combination of predetermined rectangular and non-rectangular areas based on the shape of the rectangular and non-rectangular areas. An exposure pattern generation method for equally dividing an exposure pattern into rectangular patterns to generate an exposure pattern, wherein the drawing start point of the rectangular pattern corresponding to the non-rectangular region portion is not affected by a proximity effect with a pattern adjacent in a predetermined direction. It is configured to move to the position.

In this case, when a predetermined corner portion of the rectangular pattern is set as a drawing start point based on a hypotenuse serving as a reference of the non-rectangular area portion and the rectangular patterns are sequentially generated in a predetermined direction, pattern generation is performed. In the direction perpendicular to the predetermined direction which is the direction, the drawing start point is ½ of the distance difference in the vertical direction between the drawing start point of the rectangular pattern and the drawing start point of the rectangular pattern next to the rectangular pattern. Is preferably moved.

[0011]

In the present invention, the drawing start point of the rectangular pattern corresponding to the non-rectangular region portion is moved in the predetermined direction by the predetermined amount, so that the unnecessary protruding portion due to the proximity effect in the proximity portion of the pattern is suppressed, and the fine protrusion is reduced. Pattern is drawn with high accuracy.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of an exposure pattern generating method according to the present invention, and FIG. 1 is a diagram showing a method of dividing a non-rectangular region when generating an exposure pattern according to the present embodiment. In FIG. 1, the same numbers as the numbers given to the conventional example shown in FIG. 4 indicate the same parts, and the basic electron beam exposure processing procedure is the same as that shown in FIG.

The exposure pattern generating method of this embodiment is shown in FIG.
Considering the case where the left and right symmetric parallelograms are lined up, the drawing start points O ₁ and O ₂ and the sizes L _X and _LY are read in as electron beam drawing pattern data, similar to the conventional example. And is divided into strips each having a width R. Here, in the conventional method, the lower left corner of the rectangular rectangular pattern is set as the drawing start point based on the hypotenuse serving as the reference of the non-rectangular area portion in the figure, and the arrow S in the figure is set. Although the rectangular pattern is sequentially generated in the direction of, in the present embodiment, in the non-rectangular area located on the left side of the figure, R / 2 is upward in the figure, while the non-rectangular area located on the right side of the figure is In the area, drawing is performed by moving the drawing start point by R / 2 in the downward direction in the drawing.

As a result, the left-right symmetry is maintained, and an unnecessary protruding portion due to the proximity effect in the proximity portion of the pattern is prevented. As described above, in this embodiment, by moving the drawing start point of the rectangular pattern corresponding to the non-rectangular region portion in the predetermined direction by the predetermined amount, it is possible to suppress an unnecessary protruding portion due to the proximity effect in the proximity portion of the pattern. , A fine pattern can be drawn with high accuracy.

Therefore, electron beam drawing can be performed while maintaining high positional accuracy. In the above example, the movement amount of the drawing start point is set to half the distance in the lateral direction of the divided rectangular pattern, but the present invention is not limited to this, and changed to such an extent that an unnecessary protruding portion due to the proximity effect in the proximity portion of the pattern is suppressed. It doesn't matter.

[0016]

According to the present invention, by moving the drawing start point of the rectangular pattern corresponding to the non-rectangular region portion in the predetermined direction by the predetermined amount, it is possible to suppress an unnecessary protruding portion due to the proximity effect in the proximity portion of the pattern. Therefore, a fine pattern can be drawn with high accuracy. Therefore, electron beam drawing can be performed while maintaining high positional accuracy.

[Brief description of drawings]

FIG. 1 is a diagram showing a method of dividing a non-rectangular region when generating an exposure pattern according to this embodiment.

FIG. 2 is a diagram showing a procedure of electron beam exposure processing.

FIG. 3 is a diagram showing an example of design data and electron beam drawing pattern data.

FIG. 4 is a diagram showing a method of dividing a non-rectangular region when generating an exposure pattern in a conventional example.

[Explanation of symbols]

 1 Design device 2 Conversion processing device 3 Electron beam drawing device

Claims (2)

[Claims] 1. An exposure pattern generation method for generating an exposure pattern by equally dividing a drawing pattern consisting of a combination of predetermined rectangular / non-rectangular regions into a predetermined rectangular pattern based on the shape of the rectangular / non-rectangular regions. An exposure pattern generation method comprising: moving a drawing start point of a rectangular pattern corresponding to the non-rectangular region portion to a position that is not affected by a proximity effect with an adjacent pattern in a predetermined direction. 2. A pattern generation direction when a predetermined corner portion of the rectangular pattern is set as a drawing start point based on a hypotenuse serving as a reference of the non-rectangular region portion and the rectangular patterns are sequentially generated in a predetermined direction. In the direction perpendicular to the predetermined direction, the drawing start point is moved by 1/2 of the distance difference in the vertical direction between the drawing start point of the rectangular pattern and the drawing start point of the rectangular pattern next to the rectangular pattern. The exposure pattern generation method according to claim 1, wherein