MULTILAYER FILM WITH EXTREME ULTRAVIOLET SPECTRUM PURITY AND THERMAL STABILITY

摘要

A multilayer film with extreme ultraviolet spectrum purity and thermal stability, which relates to the technical field of extreme ultraviolet lithography and solves the technical problem of severe reduction of reflectivity at an extreme ultraviolet waveband under the long-time bombardment of high-energy photons due to high reflectivity of an extreme ultraviolet multilayer film at an out-of-band waveband in the prior art. The multilayer film sequentially comprises a substrate (1), a cycle layer (2), a first spectrum purification layer (3), a first thermal stability layer (4), a first Mo layer (5), a second thermal stability layer (6), and a second spectrum purification layer (7) from bottom to top, wherein the number of cycles of the cycle layer (2) is 40 to 60, and each cycle is sequentially composed of a Si layer (21), a third thermal stability layer (22), a second Mo layer (23) and a fourth thermal stability layer (24) from bottom to top. The multilayer film can improve the imaging quality of an extreme ultraviolet lithography mirror system and can prolong the service life thereof, the reflectivity at an extreme ultraviolet waveband ranges from 58% to 67%, and the reflectivity at an out-of-band waveband can be reduced to 5% below.