PHASE SHIFT MASK AND ITS PRODUCTION

摘要

PURPOSE: To provide a phase shift mask with which transfer patterns having high dimensional accuracy are obtainable by an easy production stage and to provide a process for producing this phase shift mask. CONSTITUTION: This phase shift mask has a mask substrate 1 consisting of a transparent material, light shielding films 2 as mask patterns having plural apertures formed in the selective regions of the main surface of this mask substrate 1 and grooves 10 for phase shifters disposed on the main surface of the mask substrate 1 in at least >=1 pieces of the apertures among the plural apertures of these light shielding films 2. These grooves 10 for phase shifters are formed by a first etching stage which executes dry etching and a second etching stage which executes wet etching and the bases of the grooves 10 for phase shifters are formed by the second etching stage, by which the phase shift mask is obtd. The phase shift mask having the grooves 10 for phase shifters which are the transfer patterns having the high dimensional accuracy is thus obtd.