Patent ID: 9229315
Filing Date: 2016-01-05
CPC Classification: B82Y,G03F

Claim Text:
1. A reflective mask blank, comprising: a substrate, a multilayer reflective film formed on the substrate and adapted to reflect exposure light, a protective film formed on the multilayer reflective film and composed mainly of ruthenium (Ru) or its compound, a tantalum-based material film formed on the protective film and mainly containing tantalum (Ta), and an upper layer formed on the tantalum-based material film, wherein the upper layer does not substantially contain tantalum (Ta) and is formed of a material composed mainly of a nitride, an oxide, an oxynitride, a carbide, a carbonitride, or an oxycarbonitride of at least one or more elements selected from silicon (Si) and chromium (Cr).