JPH05120374A - Setting method for slit for pattern verification - Google Patents

Abstract

PURPOSE:To decrease the number of slits for verification and to set the slits for accurate and efficient pattern verification by approximating a pattern with segments having predetermined angles. CONSTITUTION:Straight lines 402-405 which are parallel or perpendicular to the slits are virtually drawn from the borders of the slits and their intersections 311 and 312 and lines 413 and 414 which are closer to a contact 401 among intersections 412-415 with a straight line 400 are selected. Namely, segment arrays 53-56 are approximated with segment arrays 543-545. Segment arrays 513 and 515 and 543-545 newly have vertices 611 and 612 in a slit area C. Slits of a 2nd stage are drawn from the coordinates of the vertices 611 and 612 which are generated by the approximation of the segment arrays to form new slit areas D3-D5. In this case, the number of vertices present in the slit area C drawn by the 2nd-stage operation decreases, so that the number of slits can be decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a slit setting method for verifying the layout of a pattern, and more particularly, when processing a large amount of mask pattern data of a large-scale integrated circuit device with an electronic computer, a side of an arbitrary angle. The present invention relates to a method for setting a pattern verification slit, in which mask pattern data including a figure composed of is divided into many slits and layout verification is performed for each slit.

[0002]

2. Description of the Related Art Conventionally, when handling a large amount of mask pattern data of a large-scale integrated circuit device, various techniques have been used to efficiently and practically process the mask pattern data.
One of the methods is to use a mask pattern for the vertices of a figure,
There is a slit verification method that divides into areas called elongated slits based on the coordinates of intersections of line segments and executes verification processing for each of the slit areas. FIG. 10 shows a pattern verification method using a slit.
An example of setting a slit in a pattern is shown. Figure 10
In, the pattern is a line segment parallel to the X-axis direction (for example, 10 −1) and a line segment perpendicular to the X-axis direction (for example, 1
0-2), a line segment having an inclination of 45 degrees with respect to the X-axis direction (for example, 10-3) is used as a side. And in the example shown in FIG. 10, the direction parallel to the X-axis direction is set as the slit direction. A line parallel to the X-axis direction is drawn with the vertex of the pattern shown in FIG. 10, the intersection of each line segment, or the connection between the line segment and the line segment as a reference point,
Slit regions Z1 to Z10 are formed between the drawn lines.
Are configured. The pattern verification method using such a slit is performed by the above-described subdivided slit region (Z1
To Z10) as one unit and processing is performed for each unit. However, in the pattern verification method using such slits, for example, when there are many figures that are used for high-density mask pattern data and are composed of sides of arbitrary angles, the number of slits increases too much. I will end up. Therefore, the processing speed of verification becomes slow,
Alternatively, there is a problem that the amount of memory used for verification increases and the processing efficiency for verification decreases.

FIG. 5 shows an example of a pattern composed of a large number of sides at arbitrary angles. In FIG. 5, the pattern is
It is composed of sides 1 to 60 at an arbitrary angle. Also,
The slit direction in the example shown in FIG. 5 is set to the X-axis direction. FIG. 6 shows apexes that serve as a reference when setting the slits. The vertices of the pattern shown in FIG.
It is indicated by the numbers 101 to 160. FIG. 7 shows a portion where line segments forming a pattern are connected to each other, that is, a slit is cut based on an apex.
In FIG. 7, slits A1 to A27 are cut in the Y-axis direction with the vertices 101 to 160 of the pattern as reference points.

Further, as another slit setting method in the conventional example, there is a method described in JP-A-2-33666. FIG. 8 shows another slit setting method in the conventional example. In FIG. 8, the patterns are those shown in FIGS.
The same configuration as that shown in (3) and the slit direction is also parallel to the X-axis direction. A Y coordinate parallel to the slit direction, a Y coordinate of a start point and an end point of a line segment perpendicular to the slit direction, and a straight line parallel or perpendicular to the slit direction are connected to the connection points of the two line segments in the pattern. The position is the reference point for creating the slit. Further, in the processing for designating the slit, each line segment row in the pattern in the slit is replaced with a line segment consisting of one straight line. In the above slit setting method, only when the line segment that approximates the line segment sequence with one straight line does not satisfy the rule value by some check,
The efficiency of the processing is improved by checking the line segment sequence in the actual pattern.

When the slits of the patterns shown in FIGS. 5 and 6 are cut in accordance with the above slit setting method, the patterns shown in FIG. 8 are obtained. Start point and end point 114 of a line segment perpendicular to the slit,
115, 129, 130, 131, 145, 146, 1
60 and two straight lines parallel to or perpendicular to the slit direction (for example, 1 in FIG. 5).
8 and 19) are in contact with each other (103, 10 in FIG. 8).
7, 111, 118, 122, 126, 134, 13
8, 142, 149, 153, 157), and slits parallel to the X-axis direction based on the coordinates are created. As a result, B1 to B7 shown in FIG.
The slit area of is cut. The line segment array in each slit region cut as described above is approximated by a line segment connecting two points where the line segment array intersects the boundary of the slit region. For example, pay attention to the portion indicated by the hatched portion 200 in FIG. FIG. 9 is an enlarged view of the shaded portion of FIG. 8 and is an explanatory diagram for making each line segment in the slit region into one line segment. In FIG. 9, there are line segments 16, 17, and 18 in the slit region B2. This line sequence 16, 17, 1
The points where 8 intersects with the boundary lines 201 and 202 of the slit region B2 are 281 and 282. The line segment 255 in which the points 281 and 282 are short-circuited is the line segment sequence 1 in the slit region B2.
6, 17, and 18 are approximated (hereinafter, the line segment introduced to approximate the line segment sequence like this line segment 255 is referred to as an approximate line segment). Similarly, line segments 53, 54, 55, 56
Is approximated by line segment 265. And the slit area B
In the rule verification in 2, the line segments 16, 17, 18 and the line segments 53, 54, 55, 56 are replaced by approximate line segments 255.
And the approximate line segment 265. For example, in the verification in the slit area B2, it is checked whether or not the space between the double-headed arrows 270 shown in FIG. 9 is open. In this case, the interval between the approximate line segment 255 and the approximate line segment 265 is
It is checked whether or not the distance indicated by the double-headed single-point arrow 270 is maintained, and according to a predetermined rule, it is verified whether or not the distance of the double-headed single-point arrow 270 is maintained. No error is output. If the check determines that the constant distance is not maintained, the actual line segment rows 16, 17, 18 and the line segment rows 53, 54, 55, 5 of the pattern are determined.
Detailed verification will be conducted between 6th and 6th.

[0006]

However, when the slits are set for the patterns shown in FIGS. 5 and 6, since the deviation point of the line segment is used as a reference, as shown in FIG. The number of slits increases. Therefore, the verification method using this slit has a low processing speed and a large amount of memory to be used for verification, resulting in poor efficiency. Further, in the method shown in FIG. 9, for example, the line segment rows 16, 17, 18
Between the line segment and the line segment lines 53, 54, 55, and 56, a double-headed single-pointed arrow 270 indicating a distance that is a predetermined rule value.
However, the rule value is satisfied between the approximate line segment 255 and the approximate line segment 265. Therefore, in the verification method by setting such a slit,
In some cases, errors in the layout pattern could not be found. Further, in the above method, the approximate line segment used instead of the line segment sequence of an arbitrary angle forming the pattern has an arbitrary angle again. Therefore, when verifying an approximate line segment of an arbitrary angle, a tool that can process each angle of the approximate line segment is required. Therefore, there is a problem in that the processing efficiency for verification is poor because a dedicated tool for handling only sides having inclinations of 0, 45, and 90 degrees with respect to the coordinate axis cannot be used.

The present invention is intended to solve the above problems. By approximating a pattern by a line segment having a predetermined angle, the number of slits for verification can be reduced and the accuracy and efficiency can be reduced. The purpose is to provide a good pattern verification method.

[0008]

In order to achieve the above-mentioned object, a method for setting a pattern verification slit according to the present invention is provided with X
Either the axial direction or the Y-axis direction is set as the slit direction, the position of the line segment parallel to the set slit direction, the positions of the start and end points of the line segment perpendicular to the slit direction, and the slit direction The first reference (114, 115, 129 in FIG. 1) that consists of the position where the connection points of the two line segments in the pattern contact a straight line that is parallel or perpendicular to
130, 131, 160, 145, 146, 103, 1
07, 111, 119, 122, 126, 134, 13
8, 142, 149, 153, 157) and a line segment line having an inclination other than parallel or perpendicular to the slit (1 in FIG. 2).
6, 17, 18, 19, 53, 54, 55, 56, 5
7) is a line segment having an angle of 45 degrees with the slit direction (Fig. 2
No. 400, 500), a line segment parallel to the slit (403, 405, 505 in FIG. 2) and a line segment perpendicular to the slit (404, 504 in FIG. 2). 403, 400, 404 of FIG. 2 and 5 of FIG.
04, 500, 505) which is the second criterion (FIG. 2).
414, 514) and to set the slit.

[0009]

[Operation] According to the present invention, the slit setting when performing layout data verification including many figures having sides with an arbitrary angle is performed by setting the position of the line segment parallel to the slit direction and the line segment perpendicular to the slit direction. For example, X based on the Y coordinate value of the first reference consisting of the positions of the start point and the end point and the position where the connection points of two line segments in the pattern contact a straight line parallel or perpendicular to the slit direction. If you draw a line parallel to the axis, a slit will be created between the drawn lines. Further, an approximate line segment that approximates the line segment of the pattern between the slits by a line segment having an angle of 45 degrees with the slit direction and line segments parallel and perpendicular to the slit is provided. Then, for example, a line parallel to the X-axis direction is drawn from the vertex formed by this approximate line segment, and this line is taken as one line of the slit. When the slits are set in this way, the coordinate value that serves as a reference for setting the slits can be reduced, so that the number of slits in the pattern can be reduced. Therefore, the pattern verification slit setting method of the present invention can reduce both the data amount and the processing time for verifying the pattern.

Further, the approximate line segments that are approximated when setting the pattern verifying slit of the present invention are the line segments of the pattern between the slits which are parallel to and perpendicular to the slit and the line segment having an angle of 45 degrees with the slit direction. Since it is approximated to be surrounded by a line segment, for example, Japanese Patent Laid-Open No. 2-3366
An error that cannot be detected by the verification method described in Japanese Patent No. 6 can be detected.

Further, in order to reduce the number of slits for verification, the line segment sequence of the pattern is set at 0 degrees with respect to the coordinate axis, 4 degrees.
Since the approximation is performed only with the line segments of 5 degrees and 90 degrees, it is possible to use a dedicated tool that handles only the line segments of these angles for the verification of the approximation line segments, which also improves the efficiency. You can

[0012]

EXAMPLES An example of the present invention will be described with reference to FIGS. FIG. 1 is an explanatory diagram for setting a slit in the first stage of the embodiment of the present invention. The setting of slits used for pattern verification is processed in two stages. First, the slit direction is set to either the X-axis direction or the Y-axis direction. For example, in this embodiment, the X-axis direction is set to the slit direction. In the first step of setting the slit, the pattern of the position of the line segment parallel to the slit, the coordinates of the start and end points of the line segment perpendicular to the slit, and the straight line parallel or perpendicular to the slit are set. The coordinates of the points at which the connecting points of the two line segments that make up the point of contact are selected as the reference point. A slit is formed by the coordinates of the reference point and the set slit direction. Using the example of the same pattern as the conventional example, in the first stage, the slit shown in FIG. 1 is formed. That is, the coordinates 114, 115, 129, 130, 13 of the start and end points of the line segment perpendicular to the slit.
1, 160, 145, 146 and points 103, 107, 111, 119, 12 connecting the two line segments forming the pattern with respect to a straight line parallel or perpendicular to the slit.
2, 126, 134, 138, 142, 149, 15
3, 157 is the reference point. Then, the slit regions C1 to C7 are formed by drawing a line parallel to the X-axis direction based on this reference point.

In the next second stage, slit regions C1 to C
The following processing is performed on each of the line segment arrays included in 7 and oriented in directions other than parallel or perpendicular to the slit direction. 2 is a slit area C in FIG.
An enlarged view of the hatched portion 300 of FIG. 2 is shown. In FIG. 2, for example, line segments 16 and 1
Intersection 3 between Nos. 7 and 18 and boundary lines 301 and 302 of the slit region C2 including the line segment rows 16, 17, and 18
Calculate 11, 312. Line segments that are oriented in a direction other than parallel or perpendicular to the slit region C2 are 16, 17,
18 and 53, 54, 55, 56. Line segment 5 above
Pay attention to 3, 54, 55 and 56. The boundary lines 301 and 302 of the slit region C2 and the line segment rows 53, 54, 55 and 56.
The intersections of are 311 and 312, respectively. A 45-degree straight line 400 circumscribing this line segment 53, 54, 55, 56
Are prepared as shown in FIG. This 45 degree straight line 40
The method of determining the position when 0 is drawn needs to be classified according to the positional relationship between the intersections 311 and 312 of the boundary lines 301 and 302 of the slit region C2. For example, the start point and end point 153, 154, 155, 156 of each line segment of the line segment sequence,
The coordinate values of the intersections 311 and 312 of the boundary lines 301 and 302 of 157 and the slit region C2 are X + Y or X.
A point 401 suitable for drawing a circumscribing straight line 400 from a point having the maximum value or the minimum value of -Y may be found and drawn so as to pass through the point. That is, for line 400,
The points 153, 154, 155, 156, 157 are subtracted from the point 155 that is the minimum value of the sum of the X and Y coordinate values. Also,
For line 500, points 115, 116, 117, 118
Is subtracted from the point 116 that is the maximum of the sum of the X and Y coordinate values.

FIG. 3 shows a line approximated by a line of 45 degrees and a slit created from the intersection of the approximate line. In FIG. 3, straight lines 402, 403, 404, and 405 that are parallel or perpendicular to the slit are virtually drawn from the boundaries of the slits and their intersections 311 and 312, respectively, and among the intersections 412, 413, 414, and 415 with the straight line 400. ,
Select the lines 413 and 414 that are closer to the contact point 401, respectively. That is, the line segment sequences 53, 54, 55, 56 are approximated by the line segment sequences 543, 544, 545. Similarly,
The line segment rows 16, 17, 18, and 19 are the line segment rows 513 and 51.
It is approximated by 4, 515. These line segments 513, 51
4, 515 and 543, 544, 545 newly have vertices 611 and 612 in the slit region C. In this way, the vertex 6 created by the approximation operation of the line segment sequence
From the coordinates of 11 and 612, the slit in the second stage is used as a reference. Then, as shown in FIG. 3, new slit regions D3, D4, D5 are formed. In the case of this example, the slit area C drawn by this second-stage operation
The number of vertices present within is reduced, which in turn reduces the number of slits that will eventually be created than if not approximated.

FIG. 4 shows an example in which slits are cut by the method of the present invention. In FIG. 4, line segments 501 to 548 are line segments that approximate line segments other than parallel or perpendicular to the slit. Then, the data shown in FIG. 4 is verified for each slit by the slit method. For example, in FIG. 3, when it is checked whether or not the space indicated by the double-headed arrow 270 is secured, the slit area D
Line segments 515 and 544 and line segment 5 at 3, D4, and D5
Since the rule value is not satisfied between 14 and 545,
In these slit areas D3, D4, D5, further detailed verification is performed between the original line segment rows 16, 17, 18 and 53, 54, 55, 56.

As described above, the series of approximate line segments drawn to set the slits are parallel, perpendicular, and
Limited to line segments oriented at 45 degrees. Therefore, the rule validation for the approximated data is parallel to the coordinate axes,
It is possible to use a dedicated tool that handles only the vertical and 45-degree tilt sides, and the processing efficiency for verification is improved. Further, the pattern verification slit setting method according to the present invention is not limited to the case of handling a large amount of mask pattern data of a large-scale integrated circuit device, and can be used when performing any pattern verification having an arbitrary angle. is there.

[0017]

According to the present invention, when processing graphic data having sides of an arbitrary angle, the number of slits to be processed can be reduced, so that processing efficiency can be improved. Also,
Since the approximate line segment used to reduce the number of slits is close to the actual pattern, it is possible to prevent errors from being overlooked. Furthermore, since the approximate line segment is composed of lines parallel, perpendicular, and 45 degrees to the slit, the angle-dedicated tool can be used during verification, so not only is processing speed fast, but it is also used for processing. It requires less memory.

[Brief description of drawings]

FIG. 1 is an explanatory diagram for setting a first stage slit of an embodiment of the present invention.

FIG. 2 is a hatched portion 3 of the slit region C2 in FIG.
Attention is paid to 00, and the figure which expanded this is shown.

FIG. 3 shows a line approximated by a line of 45 degrees and a drawing in which a slit is created from an intersection of the approximate line.

FIG. 4 shows an example in which slits are cut by the method of the present invention.

FIG. 5 shows an example of a pattern composed of multiple sides at an arbitrary angle.

FIG. 6 shows apexes that serve as a reference when setting a slit.

FIG. 7 shows a portion where line segments that form a pattern are connected to each other, that is, a slit is cut based on a vertex.

FIG. 8 is another slit setting method in the conventional example.

FIG. 9 is an enlarged view of the hatched portion in FIG. 8 and is an explanatory diagram for making each line segment in the slit one line segment.

FIG. 10 shows an example of setting a slit in a pattern in a pattern verification method using a slit.

[Explanation of symbols]

1 to 60 ... sides of a figure having sides with arbitrary angles given as examples 101 to 160 ... vertices of figures having sides with arbitrary angles given as examples A1 to A27 ... created by a normal slit method Slit areas B1 to B7 ... Slit areas created by a conventional method 200 ... Areas 201, 202 ... Boundary lines of slit areas B2 251 ... 266 ... Conventional The line segment 270 that approximates the line segment sequence of an arbitrary angle introduced by the method of ... Widths to be checked 281, 282 ... Line segment sequences 16, 17, 18 and 20
1 and 202 intersections 300 ... Regions 301 and 302 ... Enlarged in FIG. 2 Boundary lines of slit region C2 311, 312 ... Line segment rows 53, 54, 55, 56 and 301, 302 Intersection 400 ... A straight line circumscribing the line segment rows 53, 54, 55, 56 having an angle of 45 degrees in the slit direction 401 ... A contact point between the line segment rows 53, 54, 55, 56 and 400 402, 403. ··· Straight lines parallel to the slit drawn from 311 404, 405 ··· 312, and straight lines parallel to the slit drawn from 312 412, 413 ··· 402, 403 and intersection points 400, 414, 415 · · · 404 , 405 and 400 intersections 501 to 548 ... Line segments for approximating a line segment sequence of an arbitrary angle in the present invention 611, 612 ... Vertices D1 to serve as a reference for slit creation in the second stage Slit region in FIG. 10 the description of slit regions Z1 to Z10 ... General slit method is cut by 15 ... present invention

Claims (1)

[Claims] 1. An X-axis direction or a Y-axis direction is set as a slit direction, and a position of a line segment parallel to the set slit direction and a start point and an end point of the line segment perpendicular to the slit direction are set. And a line that has a slope other than parallel or perpendicular to the slit, and a first reference consisting of the position where the connection point of two line segments in the pattern touches a straight line that is parallel or perpendicular to the slit direction. Is defined by a line segment having an angle of 45 degrees with the slit direction, a line segment parallel to the slit, and a second reference consisting of apexes of the approximate line segment that can be approximated by a line segment perpendicular to the slit. A method for setting a slit for pattern verification, which is characterized in that