Transparent yttrium hydride thin films prepared by reactive sputtering

TL;DR

This study demonstrates the direct fabrication of yttrium hydride thin films with metallic and transparent phases via reactive sputtering, highlighting their optical and structural properties relevant for solar cell applications.

Contribution

It introduces a reactive sputtering method to produce yttrium hydride films with distinct phases without post-processing, expanding fabrication options for solar energy materials.

Findings

Films exhibit metallic or transparent properties depending on hydrogen partial pressure.

Transparent films have an fcc crystal structure, differing from the typical YH3 phase.

Films are similar optically to those made by other methods.

Abstract

Metal hydrides have earlier been suggested for utilization in solar cells. With this as a motivation we have prepared thin films of yttrium hydride by reactive magnetron sputter deposition. The resulting films are metallic for low partial pressure of hydrogen during the deposition, and black or yellow-transparent for higher partial pressure of hydrogen. Both metallic and semiconducting transparent YHx films have been prepared directly in-situ without the need of capping layers and post-deposition hydrogenation. Optically the films are similar to what is found for YHx films prepared by other techniques, but the crystal structure of the transparent films differ from the well-known YH3 phase, as they have an fcc lattice instead of hcp.