Advanced lithography needs rigorously tested fused silica glass

摘要

Alonq with SDecifvina resist uniformities, mask surface finish, and chrome, lithography engineers must pay increasing attention to the material on which a photomask is built. Demonstrated variability among fused silica mask material properties, capable of creating wavefront distortion variations >90ppm among other details, makes it imperative that the glass be specified and certified with the same rigor as the other optical components in a lithography system.