PHOTOMASK BLANKS

摘要

Transmissive embedded phase shifter-photomask blanks are disclosed which comprise an optically inhomogeneous attenuating film which has a transmission of at least 0.001 at the lithographic wavelength and consists essentially of a combination of multiple components with one of the components having a higher absorbance than another at the lithographic wavelength. One depth from a surface of the films has a higher content of the higher absorbing component than another depth and the profile of change in refractive index and/or extinction coefficient is gradual through the film thickness. Said profile(s) of change and the film thickness are selected to provide a phase shift of about 180 DEG (or an odd multiple thereof) at a selected lithographic wavelength.