Patent ID: 7724361

Claim:
An apparatus for inspecting a defect occurring in a photomask for fabrication of an image device, the photomask having a transparent substrate and a repeated pattern formed with a light shielding film on a first surface of the transparent substrate and covered with a pellicle film, said repeated pattern comprising a plurality of unit patterns arranged in a first regularity and said defect occurring as having a second regularity; said apparatus comprising: a light source which irradiates light onto the photomask, a light receiving member which receives reflected light from the photomask to produce a received light data, said received light data including pattern information of diffracted light generated at the edge part of the unit patterns, an analyzer to analyze the received light data to detect the defect occurring in the repeated pattern, and a stage for supporting the photomask in a state that the first surface of the photomask is in contact with the stage, wherein the light source irradiates the light onto the photomask from a side of a second surface of the transparent substrate, said second surface having no pattern and no pellicle film, and, the analyzer analyzes a disturbance in the regularity in the received light data caused by the defect.