Direct Growth and Electrical Properties of YH2 (111) Epitaxial Thin Films on CaF2 (111) and (001) Substrates by Reactive Magnetron Sputtering

YH2 (111) epitaxial thin films with two and four rotational crystal domains were directly grown both on CaF2 (111) and (001) substrates, respectively, at various growth temperature by reactive magnetron sputtering. The low growth temperature and the small number of crystal domains led to low resistivity in YH2 (111) epitaxial thin films, probably attributed to less hydrogen deficiency in the films. Mobility as high as 14.3 cm2/Vs was obtained at 2 K possibly due to homogeneous hydrogen distribution.