Abstract

Several laboratories are aggressively pursuing the development of soft x-ray projection lithography (SXPL) technology. The enabling technology for SXPL is the ability to produce high quality, multilayer reflectors in the soft x-ray spectral region. Mo/Si multilayers are of particular interest for SXPL since reflectivities as large as 66% have been obtained at normal incidence at 13 nm. The SXPL systems currently under development contain multiple reflective elements (typically 8:3 condensers, a reflective mask, and a four element imaging system). Marked increase in the system throughput results from slight improvements in multilayer reflectance: for an 8 element system, a 6% increase in multilayer reflectance yields a 50% increase throughput. Therefore, there is considerable interest in developing higher reflectance Mo/Si multilayer coatings.

© 1994 Optical Society of America