JPH10209000A - Apparatus and method for electron beam pattern writing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electron beam pattern writing apparatus operating at a high throughput, without deterioration the pattern writing accuracy. SOLUTION: The apparatus comprises a pattern contour width recognizer 1 for recognizing the contour width of a pattern 5 from design data, a pattern interior data creator 2 for creating pattern interior data representing the pattern interior with a max. grid in a range not influencing the pattern edges, based on the pattern contour width, a pattern edge data creator 3 for creating pattern edge data representing the pattern edges with fine grids, based on the pattern contour width and a pattern plotter 4 for drawing the pattern 5, using the pattern interior data and edge data.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electron beam writing apparatus and a pattern writing method, and more particularly to an electron beam writing apparatus for manufacturing a semiconductor device by writing a pattern using an electron beam and a pattern writing method using the electron beam. And a pattern drawing method for manufacturing a semiconductor device.

[0002]

2. Description of the Related Art A photomask used in a semiconductor device manufacturing process has a structure in which a light shielding film is formed on a glass substrate, and this pattern is mainly patterned by an electron beam drawing apparatus. Then, the semiconductor is manufactured by projecting and exposing a photomask.

Further, a semiconductor device can be produced by so-called direct drawing, in which data is drawn directly on a wafer. The beam shape of the electron beam writing apparatus used at this time is generally divided into a spot beam type and a variable shaped beam type.

A spot beam type electron beam drawing apparatus can draw a fine pattern by squeezing a narrow beam. In addition, the variable shaped beam type electron beam writing apparatus has a feature that the writing speed does not greatly decrease even if the pattern becomes fine.

On the other hand, in recent years, when the design rules of semiconductor devices have become strict and the design grid has become finer, a fine grid is required for the drawing grid so that data rounding does not occur.

[0006]

However, the spot beam type electron beam lithography system as described above has an extremely low writing speed with a fine lithography grid. There is a problem that the shot joining accuracy of the variable forming pattern is deteriorated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide an electron beam writing apparatus which performs writing at a high throughput without deteriorating the writing accuracy.

Another object of the present invention is to provide a pattern drawing method for drawing at high throughput without deteriorating the drawing accuracy.

[0009]

According to the present invention, in order to solve the above-mentioned problems, in an electron beam writing apparatus for manufacturing a semiconductor device by writing a pattern using an electron beam, a contour width of the pattern is determined from design data. A pattern contour width recognition unit that recognizes, and a pattern internal data creation unit that creates pattern internal data that is based on the contour width and that expresses the inside of the pattern with a maximum grid within a range that does not affect a pattern edge portion, A pattern edge data creation unit for creating pattern edge data expressing the pattern edge portion in a fine grid based on the contour width, and drawing the pattern using the pattern internal data and the pattern edge data And an electron beam lithography apparatus having a pattern lithography execution unit. It is.

Here, the pattern outline width recognition section recognizes the outline width of the pattern from the design data. The pattern internal data creation unit creates pattern internal data that represents the inside of the pattern with the largest grid within a range that does not affect the pattern edge, based on the pattern outline width. The pattern edge data creation unit creates pattern edge data expressing a pattern edge with a fine grid based on the pattern outline width. The pattern drawing execution unit draws a pattern using the pattern internal data and the pattern edge data.

In a pattern writing method for manufacturing a semiconductor device by writing a pattern using an electron beam, a pattern outline width is recognized from design data, and the inside of the pattern is defined as a pattern edge portion based on the recognized pattern outline width. Expressed with the maximum drawing grid within the range that does not affect the, creates pattern internal data from the maximum drawing grid, creates drawing data expressing the design data with a fine drawing grid, and creates the pattern data other than the pattern internal data. A pattern drawing method is provided, wherein drawing data is created as pattern edge data of a pattern edge portion, and the pattern is drawn using the pattern internal data and the pattern edge data.

Here, in the case of creating pattern internal data in which the inside of the pattern is represented by the largest grid within a range that does not affect the pattern edge portion, data of a variable shaped beam type may be used.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram illustrating the principle of an electron beam writing apparatus according to the present invention. The pattern outline width recognition unit 1 recognizes the outline width of the pattern 5 from the design data. The pattern internal data creation unit 2 creates pattern internal data that represents the inside of the pattern with the largest grid within a range that does not affect the pattern edge, based on the recognized pattern outline width. The pattern edge data creation unit 3 creates pattern edge data in which the pattern edge portion is represented by a fine grid based on the pattern outline width.
The pattern drawing execution unit 4 draws the pattern 5 using the pattern internal data and the pattern edge data.

Next, the operation will be described. FIG. 2 is a flowchart showing the operation of the electron beam writing apparatus of the present invention. [S1] The pattern outline width recognition unit 1 recognizes the outline width of the pattern 5 from the design data. [S2] The pattern internal data creation unit 2 creates pattern internal data that represents the inside of the pattern with the largest grid within a range that does not affect the pattern edge, based on the pattern outline width. [S3] The pattern edge data creation unit 3 creates pattern edge data expressing the pattern edge portion with a fine grid based on the pattern outline width. [S4] The pattern drawing execution unit 4 draws the pattern 5 using the pattern internal data and the pattern edge data.

Next, pattern writing of a general spot beam type electron beam writing apparatus will be described. FIG. 3 is a diagram showing an example of pattern drawing by a spot beam type electron beam drawing apparatus. This drawing is an example of pattern drawing when the design grid and the drawing grid are the same. The design grid in the pattern 50a is represented by a dotted grid, and the drawing grid is represented by a dotted circle.

FIG. 4 is a view showing an example of pattern drawing by a spot beam type electron beam drawing apparatus. This figure shows a case where the same design data is drawn with a rough drawing grid. The design grid in the pattern 50b is represented by a dotted grid, and the drawing grid is represented by a dotted circle. Also,
3 and 4 that the design data is not rounded.

FIG. 5 is a diagram showing an example of pattern drawing by a spot beam type electron beam drawing apparatus. This figure is an example of pattern drawing when the design grid and the drawing grid are the same with a pattern width different from that in FIG. The design grid in the pattern 50c is represented by a dotted grid, and the drawing grid is represented by a dotted circle.

FIG. 6 is a diagram showing an example of pattern drawing by a spot beam type electron beam drawing apparatus. This figure shows a case where the same design data is drawn with a rough drawing grid with respect to the pattern width shown in FIG. Pattern 50
The design grid in d is represented by a dotted grid, and the drawing grid is represented by a dotted circle. Here, FIG. 5 shows that the design data is not rounded, while FIG. 6 shows that the design data is rounded.

Next, pattern writing of a general variable shaped beam type electron beam writing apparatus will be described. FIG. 7 shows an example of pattern writing by a variable shaped beam type electron beam writing apparatus. In the case of the pattern 50e drawn by the variable shaping beam type, no rounding occurs regardless of the pattern width.

Next, the respective writing times of the spot beam type and the variable shaped beam type will be described. FIG. 8 is a diagram showing the writing time of each of the spot beam type and the variable shaped beam type. The vertical axis indicates the drawing time, and the horizontal axis indicates the size of the design grid, which is the design rule. Also, t
s is the spot beam type, and tv is the writing time of the variable shaped beam type.

In the spot beam type, the drawing time ts becomes significantly longer as the design rules become stricter (the design grid becomes smaller). On the other hand, in the variable shaped beam type, although the drawing time tv does not greatly change, the pattern joining accuracy does not satisfy the device specifications in the area a where the design rule is strict.

As described above, if the design rules are strict, the drawing time of the general spot beam type becomes longer, and the pattern joining accuracy of the variable shaped beam type becomes worse. Therefore, the electron beam drawing apparatus of the present invention expresses the inside of the pattern with a maximum grid within a range that does not affect the pattern edge, and expresses the pattern edge with a fine grid to perform pattern drawing. To compensate for the shortcomings, the drawing speed is not reduced even when the design rules become strict, and the pattern joining accuracy is guaranteed with high accuracy.

Next, an example of pattern writing made by the electron beam writing apparatus of the present invention will be described. FIG. 9 is a diagram showing a pattern drawing created by the electron beam drawing apparatus of the present invention. The pattern 5a in the figure is a spot beam type, and the inside of the pattern is represented by a rough drawing grid, and the pattern edge portion is represented by a fine drawing grid.

FIG. 10 is a view showing a pattern drawing made by the electron beam drawing apparatus of the present invention. This pattern 5
b is a spot beam type different from the pattern width in FIG. 9. The inside of the pattern is represented by a rough drawing grid, and the pattern edge portion is represented by a fine drawing grid. Although a design grid that is not drawn appears in the figure, it is possible to cope with the pattern contour width and process conditions without deteriorating the pattern accuracy.

FIG. 11 is a view showing a pattern drawing made by the electron beam drawing apparatus of the present invention. The inside of the pattern 5c is a variable shaped beam type, and the pattern edge portion is represented by a fine drawing grid.

FIG. 12 is a diagram showing a pattern drawing made by the electron beam drawing apparatus of the present invention. This pattern 5
d is different from the pattern width in FIG. 11, the inside of the pattern is a variable shaped beam type, and the pattern edge is represented by a fine drawing grid.

As described above, the electron beam writing apparatus of the present invention expresses the inside of a pattern with the largest grid within a range that does not affect the pattern edge, and expresses the pattern edge with a fine grid. Configuration. This makes it possible to perform pattern drawing with high throughput without deteriorating the drawing accuracy.

Next, the pattern drawing method according to the present invention will be described. FIG. 13 is a flowchart showing a processing procedure of the pattern drawing method according to the present invention. [S10] The pattern outline width is recognized from the design data. [S11] Based on the recognized pattern outline width, the inside of the pattern is represented by the maximum drawing grid within a range that does not affect the pattern edge portion. [S12] Pattern internal data is created from the maximum drawing grid. [S13] Create drawing data expressing the design data with a fine drawing grid. [S14] The drawing data other than the pattern internal data is created as the pattern edge data of the pattern edge portion. [S15] A pattern is drawn using the pattern internal data and the pattern edge data.

Next, a specific processing procedure of the pattern drawing method according to the present invention will be described. FIG. 14 is a flowchart showing a specific processing procedure of the pattern drawing method according to the present invention. [S20] The design data is input to the electron beam drawing apparatus. [S21] The input design data is subjected to a graphic logic operation,
The format is converted to a format unique to the electron beam writing apparatus. [S22] The outline width of the pattern to be drawn is recognized. Then, based on the pattern outline width by performing undersize processing, the inside of the pattern is represented by the largest drawing grid within a range that does not affect the pattern edge portion. [S23] Pattern internal data, which is a drawing grid larger than a design grid that is not aware of rounding of the design data, is created. [S24] From the design data, drawing data represented by a fine drawing grid that is not conscious of rounding of the design data is created. [S25] The pattern internal data created in step S23 and the drawing data created in step S24 are subjected to AND NOT processing to create pattern edge data of a pattern edge portion represented by a fine drawing grid. [S26] A pattern is drawn using the pattern internal data and the pattern edge data.

Next, a case where the above-mentioned AND NOT processing is performed on the electron beam drawing apparatus side will be described. FIG. 15 is a diagram showing a case where the AND NOT processing is performed on the electron beam drawing apparatus side. The drawing data 6 expressed by a fine drawing grid from the design data and the pattern internal data 2a are AND NOT-processed on the electron beam drawing apparatus side to draw a pattern 5a. In this case, the data amount of the input drawing data 6 can be reduced.

FIG. 16 is a diagram showing a case where the under-size processing and the AND-knot processing are performed on the electron beam drawing apparatus side. The electron beam lithography system performs AND NOT processing on the drawing data 6 expressed by the fine drawing grid from the design data with the pattern internal data 2a that has been undersized. In this case, the normal drawing data 6
You only have to create

As described above, according to the pattern drawing method of the present invention, the inside of a pattern is represented by the largest grid within a range that does not affect the pattern edge, and the pattern edge is represented by a fine grid. Shall be performed. As a result, without deteriorating drawing accuracy,
Pattern drawing can be performed with high throughput.

[0033]

As described above, the electron beam writing apparatus of the present invention expresses the inside of a pattern with the largest grid within a range that does not affect the pattern edge, and expresses the pattern edge with a fine grid. Pattern drawing. This makes it possible to perform pattern drawing with high throughput without deteriorating the drawing accuracy.

As described above, according to the pattern drawing method of the present invention, the inside of a pattern is represented by the largest grid within a range that does not affect the pattern edge, and the pattern edge is represented by a fine grid. Drawing was performed. This makes it possible to perform pattern drawing with high throughput without deteriorating the drawing accuracy.

[Brief description of the drawings]

FIG. 1 is a principle diagram of an electron beam writing apparatus according to the present invention.

FIG. 2 is a flowchart showing the operation of the electron beam writing apparatus of the present invention.

FIG. 3 is a diagram showing an example of pattern drawing by a spot beam type electron beam drawing apparatus.

FIG. 4 is a diagram showing an example of pattern drawing by a spot beam type electron beam drawing apparatus.

FIG. 5 is a diagram showing an example of pattern drawing by a spot beam type electron beam drawing apparatus.

FIG. 6 is a diagram showing an example of pattern drawing by a spot beam type electron beam drawing apparatus.

FIG. 7 is a pattern drawing example of a variable shaped beam type electron beam drawing apparatus.

FIG. 8 is a diagram showing respective writing times of a spot beam type and a variable shaped beam type.

FIG. 9 is a view showing pattern writing created by the electron beam writing apparatus of the present invention.

FIG. 10 is a diagram showing pattern writing created by the electron beam writing apparatus of the present invention.

FIG. 11 is a view showing pattern writing created by the electron beam writing apparatus of the present invention.

FIG. 12 is a view showing pattern writing created by the electron beam writing apparatus of the present invention.

FIG. 13 is a flowchart illustrating a processing procedure of a pattern drawing method according to the present invention.

FIG. 14 is a flowchart showing a specific processing procedure of the pattern drawing method according to the present invention.

FIG. 15 is a diagram illustrating a case where an AND NOT process is performed on the electron beam drawing apparatus side.

FIG. 16 is a diagram illustrating a case where undersize processing and AND-knot processing are performed on the electron beam drawing apparatus side.

[Explanation of symbols]

1 ... pattern outline width recognition unit, 2 ... pattern internal data creation unit, 3, ... pattern edge data creation unit, 4 ...
... pattern drawing execution unit, 5 ... pattern.

Claims (3)

[Claims] 1. An electron beam writing apparatus for manufacturing a semiconductor device by writing a pattern using an electron beam, comprising: a pattern outline width recognition unit configured to recognize an outline width of the pattern from design data; A pattern internal data creating unit that creates a pattern internal data that expresses the inside of the pattern with a maximum grid within a range that does not affect the pattern edge portion; and a fine grid for the pattern edge portion based on the contour width. A pattern edge data creating unit for creating pattern edge data represented by: and a pattern drawing executing unit for drawing the pattern using the pattern internal data and the pattern edge data. Drawing device. 2. The electron beam writing apparatus according to claim 1, wherein the pattern internal data creating section creates variable shaped beam data as the pattern internal data. 3. A pattern writing method for manufacturing a semiconductor device by writing a pattern using an electron beam, wherein a pattern outline width is recognized from design data, and a pattern edge portion is formed inside the pattern based on the recognized pattern outline width. Expressing with a maximum drawing grid within a range that does not affect the, creating pattern internal data from the maximum drawing grid, creating drawing data expressing the design data with a fine drawing grid, A pattern drawing method, wherein drawing data is created as pattern edge data of a pattern edge portion, and the pattern is drawn using the pattern internal data and the pattern edge data.