JP2002184680A - Figure data conversion method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To restrain a data amount of converted figure data, when figure data with a multilevel cell structure is converted to figure data with a fewer- level cell structure. SOLUTION: In step S202, the kind of cell reference which is a treatment object is set from cell reference, existing inside a treatment object cell. In step S203, data increase amount D1 and D2 by a first treatment, which develops cell reference alone of the kind of treatment object in higher order and a second treatment for developing cell referred to by the cell reference, are calculated. In step S204, the size of D1 and D2 is compared, and when D1<=D2, a first treatment is carried out in step S205; and when D1>D2, a second treatment is carried out in step S206.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a graphic data conversion method for converting graphic data having a multi-layer cell structure into a cell structure having a smaller number of layers.

[0002]

2. Description of the Related Art In recent years, an electron beam drawing apparatus has been used to draw a pattern of a semiconductor integrated circuit represented by an LSI on a sample such as a mask or a wafer. Graphic data for the electron beam lithography system is CAD (Computer A)
These are often created using graphic design tools such as ided Design). In such graphic design tools, for example, graphic data having a hierarchical structure of cells is used to efficiently create data. I have.

Graphic data having a hierarchical structure of cells includes structures called patterns and cells. The pattern has information on a shape such as a rectangle, a trapezoid, or a polygon, and the cell is a pattern or another cell arranged and put together. In addition, a cell hierarchy is a cell structure in which a cell has a reference to another cell. Call it a quote. Further, a case where the number of cell layers is two or more is referred to as a higher layer, and converting a cell structure of a higher layer into a cell structure of a smaller number of layers is referred to as cell expansion.

FIG. 10 shows an example of graphic data having a cell hierarchical structure. FIG. 10A shows the configuration of each cell in the graphic data, and FIG. 10B shows the hierarchical structure of the cell.

The graphic data 30 shown in FIG. 10 is composed of three cells, a cell TOP, a cell A, and a cell B, as shown in FIG. Cell TO located at the highest level
P has three cell references A and one cell reference B, each of which refers to a cell A and a cell B one layer below.
Cell A has patterns Pa1 and Pa2, and cell reference B that references cell B located in the third layer.
Patterns Pb1, Pb2, Pb3, Pb4 and Pa5
have. Such graphic data 30 is shown in FIG.
This is represented by a three-layer hierarchical structure as shown in FIG.
That is, the cell TOP is located at the first level, three cells A and one cell B are referenced at the second level, and each cell A is referenced at the third level. Cell B is located.

[0006]

By the way, in the format of the layout data created by the graphic design tool, it is possible to have a high-level cell structure, but the electron beam lithography apparatus can directly handle such a hierarchical structure. Often cannot. For example, the format of mask data for a Vexta scan type electron beam writing apparatus can have only a two-layer cell structure. For this reason, it is necessary to convert the layout data into data of a smaller number of layers so that the layout data can be accepted by the electron beam drawing apparatus. Also, depending on the size of the data amount at this time, the data conversion process may take a long time or may exceed the limit of the data amount that can be used as mask data for the electron beam writing apparatus. The data volume needs to be compressed more. In order to reduce the number of layers of graphic data, cells are expanded. There are two methods of expanding the cells: a method of expanding the graphic data in a cell to a higher layer of the cell, and a method of expanding the cells in the cell while leaving the cell. There is a way to expand the citation. Therefore,
In cell expansion, it is necessary to determine which of the two methods can reduce the amount of data.

A conventional method for converting data having a high-level cell structure into two-level data is disclosed in Japanese Patent Laid-Open Publication No. H06-26,028.
No. 29460. In this method, in each cell, the data amount of a pattern when a certain cell is expanded to a higher hierarchy is compared with the data amount of a pattern when all lower cells of the cell are expanded, and according to the comparison result. To expand cells to the top or all cells below. In the determination of the expansion method, in order to reduce the data amount of the converted two-level data, the data amount of the pattern when expanded to the upper cell is equal to the data amount of the pattern included alone by the cell. If the result of multiplying the number of cells quoted from the upper cell and the condition that the data amount when all lower cells are expanded is smaller than the data amount when expanded Expanding.

Here, as an example, a case where the graphic data 30 having the cell structure of three layers shown in FIG. 10 is converted into two layers will be described. In this expansion method, the condition determination as to whether to expand the cell A to the upper cell or to expand all the lower cells of the cell A is made after obtaining the data amount after expansion by each of the above methods.

FIG. 11 shows that a cell A is a cell TOP of an upper hierarchy.
Shows graphic data when it is expanded to. In FIG. 11, for simplicity, cell quotes are abbreviated as “at”. In the graphic data 110 shown in FIG. 11, the cell A referred to by the cell reference A included in the cell TOP of the first layer is developed in the upper hierarchy with respect to the original graphic data 30 shown in FIG. That is, the patterns Pa1 and Pa2 of the cell A and the cell reference B are developed and included in the cell TOP. When the data amount of the graphic data 110 in this case is obtained, the pattern Pa is found in the cell TOP.
1 and Pa2 are included, and one cell reference B is included. In the cell B, the patterns Pb1 to Pb5 are each 1
Are included. Here, the data amount of one pattern is P
S, assuming that the data amount of one cell reference is RS, the data amount of the graphic data 110 is (3+
3) It can be expressed as PS + 4RS + 5PS = 4RS + 11PS.

Next, FIG. 12 shows graphic data when a cell citation B in a cell A is expanded. In the graphic data 120 shown in FIG.
Are expanded in the cell A according to the pattern of the cell B. In this case, the data amount of the graphic data 120 is such that three cell references A and one cell reference are included in the cell TOP, one pattern Pa1 and one pattern Pa2 in the cell A, and one pattern Pb1 to Pb5 each. And in cell B, patterns Pb1 to Pb5
Is included in each case. Therefore, the data amount of the graphic data 120 is (3 + 1) as shown in FIG.
RS + (2 + 5) PS + 5PS = 4RS + 12PS.

Comparing the data amounts of the graphic data 110 and 120, the data amount of the graphic data 110 is 1P.
It can be seen that it is smaller by S. Therefore, it is determined that the method of expanding the cell A to the upper hierarchy can reduce the data amount, and such expansion is performed to calculate the graphic data 110. The graphic data 110 is 2
This figure data 11 has a hierarchical cell structure.
0 is finally output as the desired two-level graphic data.

As described above, the graphic data 1 shown in FIG.
10 is calculated, the pattern P in the cell A
a1 and Pa2 and cell reference B were all expanded to the upper cell. However, in this method, the condition determination is not always optimal, and the data amount of data converted into two layers cannot always be reduced.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and is intended for converting graphic data having a multi-layered cell structure into graphic data having a smaller number of layers. It is an object of the present invention to provide a graphic data conversion method capable of reducing the amount.

[0014]

According to the present invention, in order to solve the above-mentioned problem, in a graphic data conversion method for converting graphic data having a multi-layered cell structure into a cell structure having a smaller number of layers, a lower cell is referred to. Out of the cell citations indicating that the cell citation is included in the processing target cell set as the cell of the type to be processed, the cell citation is expanded to a higher cell. A first step of calculating a first data increase amount by executing a process, and a second step of executing a second process of expanding all the lower cells cited by the one type of cell citation included in the processing target cell A second step of calculating a data increase amount of the second data, and, if the first data increase amount is equal to or less than the second data increase amount, executing the first processing, increase There the second when the data increment greater than, the third step and, graphic data conversion method characterized by comprising the executing the second process is provided.

In such a graphic data conversion method, a first process for expanding only a cell citation existing in a certain cell to a higher order and a second process for expanding a cell cited in this cell citation are performed. Is determined using the data increase amount of each process, and the process with the smaller data increase amount is executed. When the first processing is executed, only the cell citations in the cell are expanded to the upper level, and furthermore, the cell expansion processing is performed for each cell citation type in the processing target cell. Compared with the conventional processing of expanding data to a higher order, the data amount of the converted graphic data can be suppressed.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. The graphic data handled in the present invention is graphic data having a hierarchical structure using patterns and cells. For example, the graphic data is supplied to an electron beam drawing apparatus for drawing a pattern of a semiconductor integrated circuit on a sample such as a mask or a wafer. Used as data. In this case, the graphic data is first created as layout data using a graphic design tool such as CAD, and is subjected to a data conversion process of converting it into mask data of an acceptable number of layers and data amount in an electron beam lithography apparatus. It is supplied to a beam drawing apparatus. The data conversion method of the present invention is realized, for example, by executing, by a processor, a program describing the procedure of such data conversion processing in a computer device. Hereinafter, a method of such graphic data conversion processing will be described.

FIG. 1 shows a flowchart of processing in the graphic data conversion method of the present invention. The flowchart shown in FIG. 1 shows a process for converting graphic data to be processed into graphic data having a two-layer cell structure.

First, in step S101, graphic data having a multi-layer cell structure is input using a graphic design tool or the like. In step S102, it is determined whether or not the processing of the following steps S104 to S109 has been completed for all types of cells in the graphic data. If the processing has been completed, the process proceeds to step S103.
The graphic data at this time is output to, for example, an electron beam drawing apparatus, and the process ends. Step S10
In step 2, if the processing has not been completed for all cells, the process proceeds to step S104. In step S104, it is determined whether the graphic data has a hierarchical structure of two or less layers. If the hierarchical structure is two or less, the process proceeds to step S103, and the graphic data at this time is output.
The process ends. If there are three or more layers in step S104, the process proceeds to step S105.

In step S105, a processing target cell indicating a cell to be processed in the following steps S106 to S109 is set from the graphic data. This processing target cell is set for one type of cell whose processing has not been completed in step S102. This setting is performed, for example, in any of the cells cited in the cell TOP of the first layer of the graphic data. , The cells referred to therein, and the cells referred to therein, descend sequentially to lower layers, and so on until reaching the lowest cell. Subsequent step S106 is an expansion method selection routine, in which a cell expansion method for the processing target cell is selected and expanded. Here, FIG. 2 shows a flowchart of the processing in the expansion method selection routine of step S106.

In the flowchart shown in FIG. 2, for a certain type of cell quotation arranged in the cell to be processed,
A process is performed to determine whether to expand only this cell citation in the upper cell or to expand the lower cell cited by this cell citation. In step S201, it is determined whether or not the processing of the following steps S202 to S206 has been completed for all cell citations arranged in the processing target cell. If the processing has been completed, the expansion method selection routine ends. Step S1 in FIG.
Proceed to 07. If the process has not been completed in step S201, the process proceeds to step S202. In step S202, of the cell citations arranged in the processing target cell, the type of the cell citation to be processed in the following steps S203 to S206 is set. We consider cell citations that refer to the same cell to be the same type of cell citation, and for all these same types of cell citations,
Perform the following processing at once.

In step S203, the data increments D1 and D2 of the graphic data by the two cell expansion methods
Is calculated. Here, the first cell expansion method is a method of expanding only the cell quotation of the type to be processed in step S202 into a higher-order cell, that is, a processing target cell. The data increase amount D1 according to this method is obtained by multiplying the data amount when the cell reference of the processing target type in the processing target cell is expanded to the upper cell and the number of times the processing target cell is cited in the upper cell. Obtained by The second cell expansion method is a method of expanding all lower cells cited by the cell reference of the processing target type, and the data increase amount D2 is a data amount when all the lower cells are expanded.

In step S204, the calculated data increments D1 and D2 are compared to select which of the first and second cell expansion methods is to be executed. Here, when the data increase D1 is equal to or less than the data increase D2, the process proceeds to step S205, and when the data increase D1 is larger than the data increase D2, the process proceeds to step S206. In step S205, the process according to the first cell expansion method is executed, and only the cell citation of the processing target type is expanded to the upper cell. Further, in step S206, the process according to the second cell expansion method is executed, and all lower cells cited by the cell citation of the processing target type are expanded. Through the processing according to the above-described flowchart, a cell expansion method that reduces the amount of data increase is selected and executed for each type of cell citation placed in the processing target cell.

Hereinafter, description will be made returning to the flowchart of FIG. In step S107, it is determined whether or not a pattern exists in the processing target cell. If the pattern exists, the process proceeds to step S108;
Return to 102. In step S108, a determination is made on the number of citations from the upper cell of the processing target cell. If the number of citations is 1, the process proceeds to step S109,
If it is not 1, the process returns to step S102. Step S1
At 09, all the patterns in the processing target cell are developed in the upper cell. Steps S108 and S109
When the number of citations of the cell to be processed is plural, the data amount is reduced by the amount cited in the cell citation by leaving a pattern in the cell to be processed. Since the amount of data for citation will be extra,
The processing in step S109 is performed, and the extra cell citation is deleted by expanding the pattern in the processing target cell. When the process in step S109 ends, the process returns to step S102.

Next, an example will be described in which specific graphic data is applied to the processing according to the above flowchart. Here, as the first graphic data example, the same graphic data as illustrated in FIG. 10 is used for comparison with a conventional graphic data conversion method. FIG. 3 shows a configuration of each cell in the first graphic data example. Less than,
The processing on the graphic data shown in FIG. 3 will be described in order with reference to the flowcharts of FIGS. 1 and 2 and FIG. 3 as needed.

The graphic data 30 shown in FIG.
It is composed of three cells, P, cell A and cell B. The cell TOP located at the highest level has three cell references A and one cell reference B that refer to lower cells, and the cell A is composed of patterns Pa1 and Pa2 and cell B.
And the cell B has the pattern Pb
1, Pb2, Pb3, Pb4 and Pa5. In the flowchart of FIG.
The graphic data 30 is input at step S102. At step S102, the end of the subsequent processing is determined. Since the processing is not completed, the process proceeds to step S104. Step S1
At 04, the number of layers is determined and the graphic data 30
Since the number of layers at this stage is three, step S10
Go to 5. In step S105, for example, first, the cell A is set as a processing target cell, and the processing of the expansion method selection routine in step S106 is started.

As described above, in the expansion method selection routine, in the processing target cell, only the first cell expansion method of expanding the cell citation of the type to be processed into the upper cell, and the cell of the type to be processed. It is selected and executed based on a second cell expansion method for expanding all lower cells cited by the citation and condition determination. For the purpose of explanation, FIG. 4 shows a configuration of the graphic data when the graphic data 30 is expanded by using each cell expansion method. FIG. 4A shows graphic data obtained by the first cell expansion method, and FIG. 4B shows graphic data obtained by the second cell expansion method. In FIG. 4, for simplicity, the cell quotation is simply abbreviated as "pull".

In the flowchart shown in FIG. 2, it is determined in step S201 that the processing of this expansion method selection routine has been completed. Since this processing has not been performed, step S20 is performed.
Proceed to 2. In step S202, the type of cell citation to be processed is set to cell citation B. That is, at this point, the cell reference B located in the cell A which is the processing target cell is set as the processing target of the expansion method selection routine. In step S203, data increments D1 and D2 by two cell expansion methods are calculated.

Here, the result of processing the graphic data 30 by the first cell expansion method is the graphic data 41 shown in FIG. 4A, and the result of the processing by the second cell expansion method. The result of the processing is the graphic data 42 shown in FIG. The first cell expansion method is a method of expanding only the cell reference B arranged in the cell A which is the processing target cell to the upper cell, and as a result, as shown in FIG. The placed cell reference B is cell TO
P, and patterns Pa1 and Pa
Only 2 remains. The data increase at this time is indicated by a dotted line in FIG. Here, assuming that the data amount of one pattern is PS and the data amount of one cell reference is RS, the data increase amount D1 by the first cell expansion method is the cell increase B1 of the cell reference B moved from the cell A into the cell TOP. Data amount 1RS
Next, the cell to be processed in the cell TOP, that is, the cell A
3RS multiplied by the number of citations 3

On the other hand, the second cell expansion method is a method of expanding all lower cells cited by the cell citation B, which is a cell citation of the type to be processed, and as a result, as shown in FIG. The cell reference B arranged in the cell A is expanded and changed to patterns Pb1 to Pb5. The data increase at this time is the patterns Pb1 to Pb5 in the cell A indicated by the dotted line in FIG. 4B, and the data increase D2 is the data amount 5PS of the patterns Pb1 to Pb5.

Next, in step S204, the data increments D1 and D2 are compared. D1 = 3RS, D
Although 2 = 5PS, in general, the cell quotation indicating information of only the arrangement quoting the cell has a smaller data amount than the pattern indicating the information of the figure, so that D1 <
D2 is determined, and the process proceeds to step S205. In step S205, the graphic data 30 is processed by the first cell expansion method, and the graphic data 41 shown in FIG. 4A is calculated. Here, returning to step S201,
Since the processing has been completed for all the cell references in the cell A which is the processing target cell, the cell expansion method selection routine ends, and the process proceeds to step S107 in FIG.

In step S107, since there is a pattern in the graphic data 41 in the cell A which is the processing target cell, the flow advances to step S108. In step S108, in the graphic data 41, the cell A which is the processing target cell
Is quoted in the top cell, so that
The process returns to step S102 again. Step S102
In, since the processing for cell B has not been completed, the process proceeds to step S104. In step S104, the cell B has no cell citation, and the cell citation arranged in the cell A has already been expanded to a higher rank. Therefore, the number of layers of the graphic data 41 is 2, and the step S1
In step 03, the graphic data 41 is output, and the process ends.

FIG. 5 is a diagram for comparing the present invention and the conventional graphic data conversion method. FIG.
(A) shows the graphic data conversion method of the present invention, and (b) shows the graphic data when the conventional graphic data conversion method is used. Note that in FIG. 5, as in FIG. 4, for simplicity, the cell quotation is simply shown as "pull".

FIG. 5 shows graphic data obtained by processing the graphic data 30 by using the present invention and the conventional graphic data conversion method. Here, the conventional graphic data conversion method refers to the amount of data when all the contents of a certain cell are expanded to the upper cell and the amount of data when all the lower cells of the cell are expanded in the graphic data. Compare and expand cells higher depending on the result of the comparison,
This is a method of determining and executing a lower cell. In the graphic data 30, the data amount is smaller when the cells are expanded into the upper cells. That is, when the conventional graphic data conversion method is used, all the cell citations and patterns arranged in the cell A are expanded to the upper cells, the cell citation A disappears, and the graphic data shown in FIG. 50 is output. On the other hand, when processing is performed on the graphic data 30 using the graphic data conversion method of the present invention,
As described above, the graphic data 41 shown in FIG. 5A is output.

Here, comparing the two data amounts, as shown in FIG. 5, the data amount of the graphic data 41 output by the processing of the present invention is 7RS + 2PS + 5PS = 7.
RS + 7PS, and the data amount of the graphic data 50 output by the conventional processing is 4RS + (2 + 2 + 2) PS
+ 5PS = 4RS + 11PS. The difference in data amount is 3RS-4PS. However, since the pattern data amount PS is larger than the cell quoted data amount RS, 3RS-4PS <0, and the graphic data 4
It can be seen that the data amount of No. 1 is smaller.

As described above, in the processing according to the flowchart shown in FIG. 1, in the expansion method selection routine of step S106, a certain kind of cell reference arranged in the processing target cell is referred to. Only the process of expanding only the upper cell and the process of expanding the lower cell cited by the cell citation are converted into graphic data having a smaller number of hierarchies by the processes in steps S203 to S206 in FIG. In this case, the data amount can be reduced as compared with the related art. Such processing is the focus of the graphic data conversion method of the present invention, and is used when converting layout data for an electron beam lithography apparatus having a high-layer cell structure into mask data having a cell structure of a lower layer. , The growing amount of data is suppressed,
For example, it is effective when creating graphic data for an electron beam drawing apparatus, such as speeding up input / output and data transfer in data processing. In addition, by changing the type of cell citation to be processed and executing the processing in steps S201 and S202 for executing the above-described processing for all cell citations arranged in the processing target cell, The effect of suppressing the data amount becomes more remarkable.

Further, in addition to the expansion method selection routine, when a pattern exists in the processing target cell and the number of cell references citing the processing target cell itself is 1, all the patterns in the processing target cell are deleted. The processing in steps S107 to S109 to be expanded to the upper cell and the processing up to this point are changed by changing the type of the cell set as the processing target cell so that the number of layers is 2 or less for all the cells in the graphic data. Steps S102 to S105 to be executed until
By executing the processing in the above, when the graphic data is converted into two-layer graphic data composed of only the cell citation arranged in the cell TOP and the pattern included in the cell cited, the data amount of this graphic data is reduced. It is possible to make it smaller.

Next, a second example of graphic data will be described with reference to FIG.
The processing when applied to the processing according to the flowchart of FIG. 2 will be described. FIG. 6 shows the configuration of each cell in the second graphic data example. 7 and 8
FIG. 7 shows a state of change in the process of the second example of the graphic data. In FIGS. 6, 7 and 8, the cell quote is abbreviated as "quote" for simplicity. Hereinafter, the processing for the graphic data shown in FIG. 6 will be described step by step with reference to the flowcharts of FIGS. 1 and 2 and FIGS. 6, 7 and 8 as appropriate.

The graphic data 60 shown in FIG.
It is composed of five cells P, cell A, cell B, cell C and cell D. Cell TOP has three cell references A and one cell reference B and D, cell A has patterns Pa1 and Pa2, and cell references B and C, and cell B has patterns Pb1, Pb2, and Pb3. , Pb
4 and Pb5, cell C has pattern Pc1, and cell D has patterns Pd1 and Pd2 and cell reference B.

In the flowchart of FIG. 1, the graphic data 60 is input in step S101, and the process proceeds to step S10.
In step 2, it is determined that the processing has not been completed, and the flow advances to step S104 to determine the number of layers. Since the number of hierarchies of the graphic data 60 at this stage is three, step S
Proceed to 105. In step S105, first, for example, the cell A is set as a processing target cell, and the process proceeds to step S10.
The processing of the development method selection routine of No. 6 is started.

Here, in the flowchart of FIG.
In step S201, it is determined that the processing of the expansion method selection routine is completed. Since there is a cell citation that has not been processed, the process proceeds to step S202, and the type of the cell citation to be processed is set to cell citation B as an example. . In step S203, data increments D1 and D2 by two cell expansion methods are calculated. Data increase D1
Is a value obtained by multiplying the data amount when the cell reference B is expanded in the upper cell, that is, the cell A, by the number of references of the cell A, so that D1 = 3RS. Further, the data increase amount D2 corresponds to the patterns Pb1 to Pb5 included in the lower cell of the cell reference B.
Is the data amount when the data is expanded to a higher order, so that D2 = 5
PS. In step S204, since D1 <D2 because of the condition of RS <PS, the process proceeds to step S205, and the cell reference B is expanded in the upper cell.

Here, FIG. 7A shows graphic data in a case where the cell reference B is expanded in the upper cell TOP. In the graphic data 71, three cell references B are newly arranged in the cell TOP, and the cell reference B is removed from the cell A. Subsequently, the process returns to step S201, and since there is a cell that has not been processed, the process proceeds to step S202. Since cell citation C is arranged in cell A,
In step S202, the type of cell citation to be processed is set to cell citation C, and in step S203, data increments D1 and D2 are calculated. Cell TO
Since three cell citations A are arranged in P, the data increase amount D1 = 3RS, and when the pattern Pc1 of the cell C is expanded in the cell A, the data increase amount D2 = PS. .

Here, if only the condition of RS <PS is satisfied, D
Although the magnitude relationship between 1 and D2 cannot be determined, RS, which is the data amount of the cell quote, and PS, which is the data amount of the pattern.
Is a value uniquely defined in the graphic data. Here, the process is advanced by further defining the values of RS and PS. For example, RS is the cell number indicated by the citation, the X coordinate and the Y coordinate to be arranged.
Assuming that PS is the size of one rectangle, the PS is represented by four elements: an X coordinate, a Y coordinate, a width W of the rectangle, and a height H of the rectangle. When the data amount of each element is the same, the condition of RS <PS <2RS is satisfied. Therefore, according to this condition, 3RS> PS, and it is determined that D1> D2 in step S204, and the process proceeds to step S206, where cell C is deployed in cell A. As described above, the case where the process of step S206 is selected means that the number of citations from the top of the processing target cell is large and the data amount of the pattern in the cell referred to by the cell citation of the processing target type is small. I can say.

FIG. 7B shows graphic data when the cell C is expanded in the cell A. In the graphic data 72, the cell reference C is removed from the cell A, and the pattern Pc1 is arranged. Subsequently, the flow returns to step S201, and the processing for all cell citations in the cell A, which is the processing target cell, has been completed. Therefore, the expansion method selection routine ends, and the flow returns to FIG. 1 to step S10.
Go to 7. In step S107, since a pattern exists in the cell A which is the processing target cell, step S107 is performed.
Proceeding to 108, the flow returns to step S102 because the number of references to cell A in the upper cell TOP is 3.

In step S102, since cells to be processed remain, the flow advances to step S104. Since the graphic data 72 has three layers, the flow advances to step S105. In step S105, for example, a cell D having a cell citation is set as the next processing target cell, and step S105 is performed.
The process proceeds to a development method selection routine of 106. In step S201 of FIG. 2, since the following processing has not been completed for the cell quote B in the cell D, the process proceeds to step S202, and the type of the cell quote to be processed is set to the cell quote B. In step S203, data increments D1 and D2 are calculated. Cell reference D is 1 in cell TOP
And the data increase amount D1 = RS, and when the patterns Pb1 to Pb5 of the cell B are developed in the cell D, the data increase amount D2 = 5PS.
Becomes Therefore, in step S204, D1
<D2, and in step S205, the cell B is expanded in the upper cell TOP.

Here, FIG. 8A shows that the cell B is replaced with the cell TOP.
The figure data when expanded in the figure is shown. In this graphic data 81, the cell B is arranged in the cell TOP, and the cell reference B in the cell D is removed. Subsequently, the flow returns to step S201, and the processing for all the cell citations in the cell D, which is the processing target cell, has been completed. Therefore, the expansion method selection routine ends, and the flow returns to FIG. 1 to step S10.
Go to 7. In step S107, since a pattern exists in the cell D, the process proceeds to step S108. Since the number of references of the cell D in the upper cell TOP is 1, the process proceeds to step S109. In step S109, all the patterns Pd1 and Pd2 of the cell D are developed in the upper cell TOP.

FIG. 8B shows graphic data when the pattern in the cell D is developed in the cell TOP. In the graphic data 82, patterns Pd1 and Pd2 are arranged in the cell TOP. As described above, the selection in step S109 is that the number of citations of the processing target cell is one.
In this case, since the data amount of the cell quote remaining in the higher order becomes excessive, this means that the extra cell quote is deleted by expanding the pattern in the processing target cell.

Subsequently, the flow returns to step S102 to determine the end of the processing. Since the processing has not been performed on the cells B and C, the flow proceeds to step S104. Step S
At 104, since the number of layers of the graphic data 82 is 2, the process proceeds to step S103,
Is output. At this time, since cells C and D are not cited, they are deleted from the data and output. FIG.
In (b), cells C and D are shown in parentheses, which means this.

Here, with respect to the graphic data 60 shown in FIG. 6 shown above as a second graphic data example, the conventional graphic data conversion method, that is, in the graphic data, all the contents of a certain cell are expanded to upper cells. Compare the amount of data when the cell is expanded and the amount of data when all the lower cells of the cell are expanded, and determine whether to expand the cell to the upper or lower cell according to the comparison result. In the case of applying the method of performing the above, and the case of applying the graphic data conversion of the present invention,
Compare the data amount of the output graphic data. In FIG.
FIG. 9 shows graphic data output when a conventional graphic data conversion method is applied to the graphic data 60. FIG.

When the conventional graphic data conversion method is applied to the graphic data 60, the processing of expanding all the contents of the quoted cell into the upper cell has a larger data amount than the processing of expanding the lower cell of the cell. Become smaller. Therefore, like the graphic data 90 shown in FIG.
, The patterns Pa1 and Pa2 arranged in the cell A and the cell quotation B are added to the cell TO by the number of cell A quotations.
Expanded to P, cell A is deleted. Further, the patterns Pd1 and Pd2 and the cell reference B, which are arranged in the cell D in the graphic data 60, are developed into the cell TOP, and the cell D is deleted. As a result, the data amount of the output graphic data 90 becomes 8RS + 14PS as shown in FIG.
Becomes On the other hand, the data amount of the graphic data 82 shown in FIG. 7B is 8RS + 10PS, and the data amount of the output graphic data is largely suppressed when the graphic data conversion method of the present invention is applied. I understand.

As described above, when the graphic data conversion method of the present invention is applied to the graphic data 60 as the second graphic data example, the processing in the development method selection routine is arranged in the cell A. The processing is performed individually for each of the two cell references B and C, and the processing target cell is set to the cell D, and the processing is performed again. Such processing makes it possible to reduce the amount of converted graphic data as compared with the conventional graphic data conversion method.

In the description of the case where the graphic data conversion method of the present invention is applied to the graphic data 60 described above, the steps in the case where the cell to be processed is cell A and the type of cell reference to be processed is cell reference C In the process of S204, RS
Although the magnitude of the data increments D1 and D2 was determined using the condition of <PS <2RS, if the definitions of the values of RS and PS are different and 3RS ≦ PS, the process in step S205 is performed. In this case, it can be seen that the data amount of the graphic data finally output by the following processing is 10RS + 10PS, which is smaller than the graphic data 90 shown in FIG. 9 to which the conventional graphic data conversion method is applied.

[0052]

As described above, according to the graphic data conversion method of the present invention, the first processing for expanding only the cell citations existing in a certain cell to the higher order, The second processing to be developed is determined using the data increase amount due to each processing, and the processing with the smaller data increase amount is executed. When the first processing is executed, only the cell citations in the cell are expanded to the upper level, and the cell expansion processing is performed for each cell citation type in the processing target cell. Compared with the conventional processing of expanding data to a higher order, the data amount of the converted graphic data can be suppressed.

[Brief description of the drawings]

FIG. 1 shows a flowchart of a process in a graphic data conversion method of the present invention.

FIG. 2 shows a flowchart of a process in a development method selection routine.

FIG. 3 is a diagram showing a configuration of each cell in a first graphic data example.

FIGS. 4A and 4B are diagrams showing a configuration of graphic data when expanded using two cell expansion methods, wherein FIG. 4A shows graphic data obtained by a first cell expansion method, and FIG. FIG.

5A and 5B are diagrams for comparing the present invention and a conventional graphic data conversion method, FIG. 5A shows graphic data when the graphic data conversion method of the present invention is used, and FIG. The figure data when the figure data conversion method is used is shown.

FIG. 6 is a diagram showing a configuration of each cell in a second graphic data example.

FIGS. 7A and 7B are diagrams showing a state of change in the process of processing the second example of graphic data; FIG.
Shows graphic data when expanded in a cell C. FIG.
Is expanded in the cell A. FIG.

FIGS. 8A and 8B are diagrams showing a state of change in the process of the second example of graphic data, wherein FIG. 8A shows graphic data when a cell B is expanded in a cell TOP, and FIG. 3 shows graphic data when the pattern of FIG.

FIG. 9 is a diagram illustrating graphic data output when a conventional graphic data conversion method is applied to a second graphic data example;

FIGS. 10A and 10B are diagrams showing examples of graphic data having a cell hierarchical structure, wherein FIG. 10A shows the configuration of each cell in the graphic data, and FIG. 10B shows the hierarchical structure of the cells.

FIG. 11 is a diagram showing graphic data when a cell A is expanded to an upper hierarchy.

FIG. 12 is a diagram showing graphic data when a cell citation B in a cell A is expanded.

[Explanation of symbols]

30, 41, 42, 50, 60, 71, 72, 81, 8
2, 90, 110, 120 ... graphic data

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G06F 17/50 658 H01L 21/30 541J

Claims (5)

[Claims] In a graphic data conversion method for converting graphic data having a multi-layer cell structure into a cell structure having a smaller number of layers, a cell reference indicating that a lower cell is cited is to be processed. For one type of cell citation included in a processing target cell set as a type of cell, a first process is performed by executing a first process of expanding the cell citation to a higher cell.
A first step of calculating the amount of data increase of the second cell, and a second data increase amount by executing a second process of expanding all the lower cells cited by the one type of cell citation included in the processing target cell. A second step of calculating; and if the first data increase amount is equal to or less than the second data increase amount, the first process is executed, and the first data increase amount is determined by the second data increase amount. And a third step of executing the second process when the data increase amount is larger than the data increase amount of the graphic data. 2. The method according to claim 1, further comprising a fourth step of executing the processing of the first, second, and third steps for all types of cell citations included in the processing target cell. The graphic data conversion method according to claim 1. 3. Following the first, second, third, and fourth steps, a pattern exists in the processing target cell, and the number of cell references that refer to the processing target cell itself is one. 3. The graphic data conversion method according to claim 2, further comprising a fifth step of expanding all the patterns in the processing target cell into the upper cell at one time. 4. The first, the second, the third, the fourth and the fifth.
Is performed on all types of the cell citations included in the processing target cell,
4. The graphic data conversion method according to claim 3, wherein the graphic data conversion method is executed by changing the type of the cell set as the cell to be processed until the graphic data has a hierarchy of 2 or less. 5. The graphic data conversion method according to claim 1, wherein said graphic data is layout data or mask data for an electron beam writing apparatus.