Methods and systems for inspecting a reticle are provided. In an
embodiment, a method may include forming an aerial image of the reticle
using a set of exposure conditions. The reticle may include optical
proximity correction (OPC) features. The method may also include
detecting defects on the reticle by comparing the aerial image to a
reference image stored in a database. The reference image may be
substantially optically equivalent to an image of the reticle that would
be printed on a specimen by an exposure system under the set of exposure
conditions. The reference image may not include images of the OPC
features. Therefore, a substantial portion of the defects include defects
that would be printed onto the specimen by the exposure system using the
reticle under the set of exposure conditions. The method may also include
indicating the defects that are detected in critical regions of the
reticle.