Patent ID: 8817367

Claim:
An extreme-ultraviolet (EUV) lithography mirror suitable for operating in the 10-15 nm range, said mirror consisting of: a selected substrate suitable for EUV lithography, said substrate having a plasma densified and smoothed surface, a coating on the densified and smoothed surface of the substrate, said coating consisting of 40-100 coating periods, each coating period consisting of a Mo layer of specified thickness in the range of 2 nm to 5 nm and an Si layer of specified thickness in the range of 2 nm to 5 nm, the deposited thickness of the Mo layer and the Si layer each being ±0.1 nm of the specified thickness, wherein the Mo layer is the first layer of each period and the Si layer is the second layer of each period; and the mirror has a reflectivity of greater than 70%.