PRODUCTION OF PHASE SHIFT PHOTOMASK

PURPOSE: To provide a process for production which does not induce the damage of light shielding parts at the time of etching and patterning a shifter layer in a stage for producing a lower shifter type phase shift photomask of a Levenson type, substrate carving-in type (Qz etch type) phase shift photomask, etc. CONSTITUTION: This process for production of the phase shift photomask of a lower shifter type comprises a substrate (blank) having, successively from a transparent substrate side, a phase shifter layer and a light shielding layer on a transparent substrate and forming, successively from the transparent substrate side, phase shifter patterns and light shielding layer patterns on the transparent substrate. After the light shielding layer patterns 14A are formed, the entire surface or part of the substrate on the light shielding layer patterns 14A is covered with a protective film 18 so that the entire part of the light shielding layer patterns 14A is covered with the protective film 18 and resist patterns 16A. The shifter layer 13 not covered with the light shielding layer patterns 14A and the resist patterns 16A is etched, by which the phase shifter patterns 13A are formed.