Patent ID: 11143949

Abstract:
Provided is a photomask blank including, on a substrate, a processing film and a film made of a material containing chromium which is formed to be in contact with the processing film and has a three-layer structure of first, second and third layers, each of which contains chromium, oxygen, and nitrogen, wherein the first layer has a chromium content of 40 atomic % or less, an oxygen content of 50 atomic % or more, a nitrogen content of 10 atomic % or less, and a thickness of 20 nm or more, the second layer has a chromium content of 50 atomic % or more, an oxygen content of 20 atomic % or less, and a nitrogen content of 30 atomic % or more, and the third layer has a chromium content of 40 atomic % or less, an oxygen content of 50 atomic % or more, and a nitrogen content of 10 atomic % or less.