| 摘要 |
SOLUTION: There is provided a half tone phase shift mask blank having a half tone phase shift film that is formed on a transparent substrate, is composed of a silicon-based material which contains silicone and nitrogen as essential constituents and may contain oxygen as an arbitrary constituent where the content of total of silicon, nitrogen and oxygen is 90 atom% or more, the content of silicon is 30-70 atom%, the content of total of nitrogen and oxygen is 30-60 atom%, the content of oxygen is 30 atom% or less, and the content of a transition metal is 1 atom% or less, and has a film thickness of 70 nm or less.EFFECT: The half tone phase shift mask blank is provided with a half tone phase shift film which is thinner and so favorable for processing a photomask pattern, is small in pattern dimension variation degradation to irradiation of light having a wave length of 200 nm or less, and secures a phase difference necessary for a phase shift film and a transmittance necessary for a half tone mask.SELECTED DRAWING: Figure 1 |
