Patent ID: 11860529
Assignee: SHIN-ETSU CHEMICAL CO., LTD.
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 21:
22. A substrate with a multilayer reflection film for an EUV mask blank comprising a substrate, and a multilayer reflection film formed on the substrate, wherein
the multilayer reflection film comprises a Si/Mo laminated portion in which Si layers and Mo layers are alternately laminated, and a protection layer containing Ru formed on the Si/Mo laminated portion and in contact with the Si/Mo laminated portion, as the uppermost layer,
the protection layer comprises a lower layer formed in contact with the Si/Mo laminated portion, and an upper layer formed at the side remotest from the substrate,
the lower layer is composed of Ru,
the upper layer is composed of a material containing Ru and at least one selected from the group consisting of metals other than Ru, and metalloids, and
a layer containing Si and N intervenes at one or more portions between the Si layer and the Mo layer of the Si/Mo laminated portion, and is contact with both of the Si layer and the Mo layer.