Phase shift mask comprises (a) a substrate (1) permeable to irradiated light, and (b) a phase shift section (20) formed in a predetermined region on the substrate which changes the phase angle of the irradiated light by approximately 180 deg and which has a permeability of 3-20% for the irradiated light. The phase shift section has a monolayer film (4) made of an homogeneous material, and a permeable layer (10) whose permeability is less dependent on wavelength when it is used in combination with the monolayer film. Prodn. of the mask is also claimed.
