Mask data processing method for optimizing hierarchical structure

Abstract

Disclosed is a mask data processing method of correcting a hierarchical structure. In the case that in design data having a hierarchical structure including a plurality of cells each having a design pattern, when the total number of graphic forms or the total edge length of a design pattern on which the calculation of mask data processing is to be executed, the amount of calculation to be executed, or the expansion degree presumably becomes equal to or larger than a predetermined threshold value if the calculation of the mask data processing is executed on the design data having the initial hierarchical structure, the hierarchical structure is corrected. This correction is performed to reduce the total number of graphic forms or the total edge length of the design pattern on which the calculation is to be executed, the amount of calculation to be executed, of the expansion degree.

1 - 11 . (canceled) 
     
     
         12 . A mask data processing method for generating mask data, wherein, when a plurality of repetitive design data regions having an identical design pattern satisfy a predetermined condition based on recommended cell structure indices with respect to design data including a plurality of cells each having a design pattern, a result of mask data processing calculation executed for a design pattern contained in one of the repetitive design data regions is applied to the repetitive design data regions for which mask data calculation processing is not executed, without performing the mask data processing calculation, said mask data processing method comprising:
 when a plurality of critical cells having an identical critical design pattern are arranged in a repeating direction the number of times not less than the predetermined number of times of repetition, a width as defined in a direction perpendicular to the repeating direction of the critical cells is less than the predetermined width, and the critical cells are adjacent, in one direction perpendicular to the repeating direction, to the same adjacent design pattern requiring a smaller calculation amount per unit area than a calculation amount required of the critical design pattern, when the calculation of the mask data processing is executed,   performing correction to increase a width of one side of the critical cells such that the critical cell includes the adjacent design pattern adjacent thereto, and the width as defined in the direction perpendicular to the repeating direction of the critical cell is not less than the predetermined width; and   executing the calculation of the mask data processing after said performing correction.   
     
     
         13 . The mask data processing method according to  claim 12 , wherein said performing correction includes correcting a hierarchical structure to increase the width of one side of the critical cells. 
     
     
         14 . The mask data processing method according to  claim 13 , wherein said correcting the hierarchical structure to increase the width of one side of the critical cells includes inputting design data and a predetermined condition to a design pattern correction tool, and enlarging existing cells to an outside region where no pattern exists. 
     
     
         15 . The mask data processing method according to  claim 13 , wherein said correcting the hierarchical structure to increase the width of one side of the critical cells includes generating a dummy pattern that defines an outline of a cell, at a position to which the outline of the cell is to be expanded, and restructuring the cell in such a manner as to encompass the dummy pattern. 
     
     
         16 . The mask data processing method according to  claim 12 , wherein the design data has a hierarchical structure including a plurality of cells. 
     
     
         17 . The mask data processing method according to  claim 13 , wherein a plurality of repetitive cells having an identical design pattern are arranged in one direction not less than the number of times of repetition predetermined based on contents of mask data processing, and a width as defined in a direction perpendicular to the direction of the repetitive cells is not less than a width predetermined based on the contents of the mask data processing. 
     
     
         18 . A mask data processing method, wherein design data is divided into a plurality of cells each having a design pattern, each of the cells has a fringe region which is adjacent to and in contact with an outer circumference thereof, and calculation of mask data processing is performed on each cell such that the calculation is also executed in the fringe region of the cell, thereby generating mask data, said mask data processing method comprising:
 changing the division to move or change the fringe region such that a calculation amount of the mask data processing in the fringe region after the division is changed is made smaller than a calculation amount of the mask data processing in the fringe region before the division is changed; and   executing the calculation of the mask data processing after the division is changed.   
     
     
         19 . The mask data processing method according to  claim 18 , wherein said changing the division includes enlarging the outline of the cell such that in the mask data processing. 
     
     
         20 . The mask data processing method according to  claim 18 , wherein the fringe region is a region that requires additionally performing calculation of mask data processing so as to introduce an optical proximity effect which peripheral regions have on the region.