Abstract

Multilayer x-ray mirrors of molybdenum and silicon operating at normal incidence at wavelengths just longward of the Si L_II,III absorption edges, are a key component in the development of soft x-ray projection lithography. In this application high reflectivity is essential. Because the achievement and maintenance of high reflectivity surfaces is vital to the success of soft x-ray projection lithography, it is important to know if Mo/Si multilayers show "aging" effects, e.g. decreasing reflectivity with time. Since, in a series of measurements of such mirrors at x-ray wavelengths, we had found evidence of such decay, a series of systematic experiments was carried out.

© 1993 Optical Society of America