High-transmission phase shift mask blank for high-definition flat panel display

Pattern dimension of photomask for flat panel display (FPD) is becoming finer year by year, and it can be seen the movement to use phase shift mask in the critical layer to improve the transfer performance to the panel. For example, transferring small contact holes with high accuracy, a high-transmission phase shift mask capable of obtaining stronger phase shift effect may be required. Currently, we are developing high-transmission phase shift mask blanks for i-line exposure using silicide-based material, and we determined stable manufacturing conditions by investigating the relationship between amount of film-forming process gas and optical properties such as refractive index n and extinction coefficient k. In addition, we confirmed that the cross-sectional shape of this new silicide phase shift film is good, and it can be formed uniformly on large substrate. In this paper, we will introduce the current development status of new silicide phase shift film and the differences from MoSi phase shift film. Moreover, we will introduce high-precision Cr-Binary film suitable for this new silicide film as well.