PHASE SHIFT PHOTOMASK AND ITS PRODUCTION

摘要

PURPOSE:To obtain a phase shift photomask and its production with a small number of manufacturing processes. little defect rate and high accuracy. CONSTITUTION:The phase shift photomask consists of a subsutrate 22, light- shielding pattern 23, and phase shifter 25 provided in a specified apperture part of the light-shielding pattern. The production method consists of a process to form a silicon film 23 as the light-shielding pattern film on the substrate 22 and a process to effect oxidation treatment 26 in a specified area of the silicon film 23 to form the phase shifter 25 comprising SiO2 by oxidation of silicon in the treated area.