| 摘要 |
This invention provides a process for producing a gray tone mask, which can reduce the dependence of wavelength on exposure wavelength under conditions for stable and easy film formation. A chromium nitride film having a single-layer structure is formed as a semi-light-transparent film using a reactive sputtering method in which a pure chromium target is sputtered under an atmosphere composed of Ar and No. In this case, an NO target concentration (an intermediate value) for bringing the homogeneity of transmittance of the semi-light-transparent film to not more than 1.0% at 365 nm to 436 nm or not more than 4.0% at 300 nm to 500 nm is determined based on a plurality of different spectral transmittance curves obtained under a plurality of film forming conditions using different NO concentrations, and a semi-light-transparent film is then formed using NO at the target concentration. |
