Patent ID: 8336004

Claim:
A method of verifying a mask, comprising: calculating, using a computer, a computational estimated value of a difference between an actual dimension of a verification target mask pattern to be a verification target extracted from a mask pattern formed on a mask and a simulation dimension of the verification target mask pattern calculated by a mask simulation when forming the verification target mask pattern, as a first difference; calculating a difference between an actual dimension of the verification target mask pattern that is actually measured and a pattern dimension of the verification target mask pattern on pattern data, as a second difference based on an actual measurement; and verifying whether a pattern dimension of the mask pattern formed on the mask passes or fails based on whether a difference evaluation value obtained by using the first difference and the second difference is within a predetermined allowable range, wherein the calculating the first difference includes calculating the first difference by applying a model function, which is set by using a test pattern formed on a mask for test, to the verification target mask pattern, and the model function is a relational expression set based on each correspondence relationship between an actual dimension of the test pattern and a simulation dimension of the test pattern that is calculated by a mask simulation when forming the test pattern, under a plurality of types of pattern ambient environments.