REFLECTION TYPE MASK BLANK AND REFLECTION TYPE MASK AND PRODUCTION METHODS FOR THEM

摘要

A reflection type mask blank comprising a substrate (11), and, sequentially formed thereon, a reflection layer (12) for reflecting an exposure light in a short-wave region including an extreme ultraviolet region and an absorber layer (16) for absorbing an exposure light. The absorber layer (16) has a structure of at least two layers consisting of as a lower layer an exposure light absorbing layer (14) composed of an absorber of an exposure light in a short-wave region including an extreme ultraviolet region, and as an upper layer a low-reflectance layer (15) composed of an absorber of an inspection light used for mask pattern inspection. The upper layer consists of a material containing tantalum (Ta), boron (B) and nitrogen (N), B content being 5 at%-30 at%, a composition ratio between Ta and N (Ta:N) being 8:1 to 2:7. Alternatively, the reflection type mask blank may comprise a substrate, and, sequentially formed thereon, a multi-layer reflection film and an absorber layer, wherein the absorber layer consists of a material containing tantalum (Ta), boron (B) and nitrogen (N), B content being 5 at%-25 at%, a composition ratio between Ta and N (Ta:N) being 8:1 to 2:7.