Photomask with phase shift layer and manufacture thereof

Abstract

Abstract PURPOSE:To stably obtain a phase shift mask which has high accuracy and is easily inspected and corrected by using photomask blanks in the structure of an etching stopper layer, a transparent thin film layer, and a light shielding thin film formed on a substrate of glass, etc., in this order. CONSTITUTION:The photomask blanks in the structure of the etching stopper layer 31, transparent thin layer 32, and light shielding thin film 33 formed on the substrate 30 in this order are used as a substrate for a phase shift reticle. In this case, the substrate 30 is formed preferably of high-impurity composite quartz glass, CaF2, etc., the etching stopper layer 31 is formed of a tantalum film, a silicon nitride film, etc., and the transparent layer 32 is formed of an SiO2 thin film, a CaF2 thin film, etc. Further, the light shielding thin film 33 is preferably a chromium thin film, a molybdenum silicide thin film, etc. Consequently, the phase shift mask which has high resolution, a high contrast, and high accuracy and is easily inspected and corrected can be obtained stably and easily.

Inventors

• 👤 Yoichi Takahashi
• 👤 洋一 高橋

Bibliographic Details