| 摘要 |
In a photo mask to transfer a mask pattern to a substrate by irradiating ultraviolet rays in a mask-pattern-forming region, an evaluation pattern having depressions in which a growable substance of the same kind as that of a foreign substance growing in the mask-pattern-forming region by ultraviolet rays on at least any one surface out of a mask-pattern-forming surface and the back surface thereof. And, the usage limit of the photo mask is evaluated according to a degree of cloudiness of the respective depressions, for instance, by irradiating the evaluation pattern with a high intensity light source. |
