| 摘要 |
PURPOSE:To prevent errors of a visual inspection, which are originally caused by a shifting within a tolerance, and to make possible the efficient visual inspection of a photomask by a method wherein a design data is corrected on the basis of a found value to automatically correct a shifting on the photomask. CONSTITUTION:At least 2 or more aligning marks A-D are formed outside of the region of a light shielding pattern on the main surface of a photomask to be inspected and after the amount of shifting between the found distance between these marks A-D and a logical distance calculated on the basis of design data is calculated, this amount of shifting is given to a measuring means as a correction value and an inspection is conducted. That is, as a found data is ready-corrected on the basis of the correction value at the time of comparison with the design data, a shifting on the photomask is also automatically corrected. Thereby, errors of a visual inspection, which are originally caused by a shifting within a tolerance, are prevented and the efficient visual inspection of the photomask becomes possible. |
