X-RAY BLANK MASK AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To obtain a product which satisfies all the required conditions of a mask by simultaneously using substance having no damage due to X-ray exposure at the site of an alignment window disposed with the mark and the site to become the X-ray exposure. SOLUTION: A first Si3 N4 thin film 42/poly-Si thin film 43/second Si3 N4 film 44 deposited on a silicon wafer are formed at a chip site 6. The site of an alignment window 5 is etched to the film 43, and formed only of the second film 44. At this time, the Si3 N4 thin film used for the window 5 has about 633nm of light permeability and about 80 or more. The window 5 is formed small to the minimum limit so that the supporting force of the permeable film is strong even if it is thin. Thus, the product which satisfies all the required conditions of the mask is obtained.