Patent ID: 8205179

Claim:
A method for approximating an average over a plurality of defect sizes of short critical areas contributed by a set of at least two object segments in an integrated circuit fabrication layer, comprising the steps of: summing using a computer system, over all the object segments i in the set, respective critical area contribution values that are dependent upon particular layout parameters of the objects in the set, each of the contribution values being representative of the plurality of defect sizes, and each of the contribution values being defined such that for each defect size x in the plurality of defect sizes, and for each pair of mutually visible object segments i and j in the set, for which x exceeds the spacing between object segments i and j, only part of the short critical area between object segments i and j is included in the contribution value of object segment i and the remainder of the short critical area between object segments i and j is included in the contribution value of object segment j; and approximating the average as a function of the sum.