Patent ID: 6253362
Filing Date: 2001-06-26
Classification: G06F,H01L

Abstract:
A method of designing dummy wiring comprising:the first step of laying out a pattern of a non-uniform density on a layout region;the second step of dividing the layout region into a plurality of sub layout regions, each of the sub layout regions having a size which is 1/4 or less of the size of the layout region;the third step of sequentially scanning the sub layout regions, obtaining the pattern density of the scanned region of each sub layout region, thereby obtaining a density distribution function concerning the pattern;the fourth step of obtaining an index indicative of variations in the density of the pattern on the layout region on the basis of the density distribution function;the fifth step of increasing, when the index is not an allowable value, the size of that portion of the pattern which is located on one of the sub layout regions, thereby updating the density distribution function; andthe sixth step of repeating the fourth and fifth steps until the index assumes the allowable value; andwherein in the fifth step, the index of the unallowable value is defined by a value which is obtained by dividing the maximum amplitude by the amplitude of a zero frequency component.