PRODUCTION OF PHASE-SHIFT PHOTOMASK BLANK, PHASE-SHIFT PHOTOMASK BLANK AND PHASE-SHIFT PHOTOMASK

摘要

PURPOSE: To provide a phase-shift photomask blank suitable to UV exposure and highly resistant to chemicals. CONSTITUTION: Gaseous nitrogen monoxide is added by 2.65-6vol.%, then a molybdenum silicide target is sputtered, and a molybdenum silicide oxynitride film is formed on a transparent substrate. This film is suitable to the phase-shift film in a KrF excimer laser wavelength and highly resistant to chemicals. Since the chemical resistance is especially improved when the proportion of the gaseoous nitrogen monoxide is low, the film is used as the protective film of the phase-shift film by adding 0.5-6vol.%. The process variation of the transmittance is reduced when the film is heat-treated at >=200 deg.C, and the transmittance is increased in the exposure wavelength.