Abstract

All conventional coatings have low normal incidence reflectance in the soft x-ray and extreme ultraviolet spectral region. Recent studies however, have demonstrated that layered synthetic microstructures (LSMs)^1-4 can provide soft x-ray and EUV mirrors with enhanced normal incidence reflectance. An LSM is a periodic multilayer thin film structure in which the refractive index varies periodically with depth. It is the analog of the quarter wave stack used for special coating designs in the optical region. In x-ray region where low absorption materials exist the ideal Bragg crystal geometry applies. EUV is a special region due to the increased absorption of all materials. Therefore, designs for maximum reflectance are obtained with a non-periodic stack to minimize absorption losses.

© 1984 Optical Society of America