| 摘要 |
PURPOSE:To obtain phase shifters with decreased fluctuations in phase with high accuracy by forming a conductive film which is a light shielding material on a glass substrate and selectively oxidizing a part thereof, thereby forming the transparent shifters. CONSTITUTION:A silicon film 2 is formed on the quartz glass substrate 1 and a silicon nitride film 3 is formed thereon, on which film a resist film 4 is applied. The shifter parts 5 are removed by an ordinary electron beam plotting method. After the exprosed silicon nitride film 3 is selectively removed, the resist film 4 is removed and the exposed silicon film 2 is oxidized by a thermal oxidation method using the silicon nitride film 3 as a mask to form the shifters 6. The misregistration defect of the shifters, etc., are prevented in this way and the phase shift mask having the decreased fluctuations in phase and the high accuracy is formed. |
