Patent ID: 8705838

Claim:
A method for mask inspection in connection with mask design and/or mask production, with respect to the mask design that has been drafted and converted into a mask layout, wherein at least one optical proximity correction has been applied during conversion of the mask design into a mask, comprising: (a) simulating an aerial image to determine a list of critical locations known as hot spots; (b) utilizing the hot spots to analyze the mask and/or the test mask with the help of an Aerial Imaging Measurement System tool, by generating real aerial images; (c) comparing the real aerial images with the simulated aerial images; and (d) utilizing the differences determined for the real aerial images and the simulated aerial images and determining whether real distortions contained in the aerial image are caused by the electron beam proximity effect or by insufficient optical proximity corrections so as to improve the design of the mask, comprising the following steps: simulating line widths and/or edge shifts for mask writing at certain critical points of measurement, and simulating optical exposure at the same points; determining characteristic signatures σ m for mask lithography and σ o for optical lithography from deviations documented for both simulations as a function of measurement point; and comparing the signatures σ m and σ o with the signature σ b of the observed values of measurement by determining correlation coefficients ρ mb with respect to the mask and ρ ob with respect to the optics, the correlation coefficients providing a measure for the influence which mask exposure or optical exposure, respectively, has on the actual observation.