Patent ID: 7640530

Claim:
A method for inspecting a mask for use in an inspection system, comprising: converting a first layout data without a defect pattern data into a first virtual photo resist pattern (PR pattern) data using a wafer simulating part as being a first step; converting a second layout data to which a defect pattern data is added by a defect setting part into a second virtual PR pattern data on a wafer using the wafer simulating part as being a second step; detecting a difference data between a first virtual PR pattern data and said second virtual PR pattern data using an affecting level judging part as being a third step; judging whether or not a defect of said defect pattern data is an allowable defect on the wafer based on said difference data using the affecting level judging part as being a fourth step; and extracting a defect, which is not the allowable defect on the wafer, as a real defect of said inspection object mask pattern, after eliminating the allowable defect on the wafer, as a pseudo defect, based on a judgment result at said fourth step, while verifying a real pattern data obtained from an inspection object mask pattern and said first layout data using a defect judging part being a fifth step.