Layered synthetic microstructure technology considerations for the extreme ultraviolet

The performance of layered synthetic microstructures (LSMs) in the extreme ultraviolet (EUV), particularly in the 300-Å spectral region, has been evaluated. Representative designs were analyzed, and experimental mirror coatings were produced. Pt–Si and Ir–Si combinations clearly demonstrate that the enhancement can be realized over a limited bandwidth of 75 Å. Preliminary results for the Ir–Si combination on a diffraction grating indicate that LSMs enhance grating efficiencies in the EUV by a factor of ~3.