Photochromic Response of Encapsulated Oxygen?Containing Yttrium Hydride Thin Films

Photochromic oxygen-containing yttrium-hydride thin films are synthesized by argon magnetron sputtering on microscope slides. Some of them encapsulated with a thin, transparent, and nonphotochromic diffusion-barrier layer either Al2O3 or Si3N4. Ion-beam-based methods prove that these protective diffusion barriers stable free from pinholes, thicknesses only few tens nanometers. Optical spectrophotometry reveals the photochromic response relaxation time for both protected unprotected samples almost identical. Ageing effects in lead to degradation performance (self-delamination), whereas is stable. The results show environment does not play decisive role process encapsulation rare-earth hydride transparent nonorganic layers provides long-time stability films, mandatory applications as coatings on, e.g., smart windows.