Patent ID: 7344806
Filing Date: 2008-03-18
Classification: C23C,G03F

Abstract:
1. A method of producing a phase shift mask blank wherein the method includes at least a step of forming two or more phase shift films having different compositions respectively on a substrate, and in the step, each of the phase shift films having different compositions respectively is formed by the sputtering method by simultaneously discharging at least one or more silicon target and one or more target selected from the group consisting of a metal silicide, a metal silicide oxide, a metal silicide nitride, a metal silicide oxide nitride, a metal silicide oxide carbide, a metal silicide nitride carbide, and a metal silicide oxide nitride carbide; further, each phase shift film is formed by continuously discharging targets used for forming any one of the layers of the phase shift films without shutdown even when the other layers of the phase shift films are formed, and a composition ratio of metal and silicon in the phase shift film is changed by adjusting discharge powers applied to each target.