Reflection mask technology for x-ray projection lithography

Abstract

We report the first demonstration of the fabrication and characterization of soft x-ray reflecting masks suitable for x-ray projection lithography. We have patterned efficient (R>50%) normal-incidence x-ray mirrors to produce reflecting masks with measured x-ray contrasts>500:1 over a sufficiently wide spectral range. Calculations indicate that masks on silicon substrates are thermally stable for a production-type lithographic facility.