Juan I Larruquert, Ritva A. M. Keski-Kuha
Reflectance measurements of ion-beam-deposited (IBD) C films were performed in the extreme ultraviolet (EUV) spectral region from 49 to 200 nm. Near normal incidence reflectance of IBD C films was determined to be higher than that of evaporated C films but lower than that of diamond. Optical constants of IBD C films were obtained from reflectance measurements as a function of the angle of incidence in the spectral range 49.0–121.6 nm. The relatively high reflectance of IBD C films in the spectral region 49–92 nm and its stability when stored in a desiccator make it an interesting coating material for the EUV.