Structural properties of Eu doped gallium oxide films

Abstract

We have investigated structural properties of Eu doped gallium oxide (Ga2O3) films grown by pulsed laser deposition at different substrate temperature. X-ray rocking curve and Raman spectroscopy measurements prove that the films grown at the substrate temperature above 400°C are of monoclinic β-Ga2O3 structure and the crystalline quality of the films depends on the substrate temperature. X-ray absorption near edge structure measurements indicate that the valence of Eu ions in the Eu doped Ga2O3 films varies from mixture of bivalent and trivalent to only trivalent with increasing substrate temperature. Extended X-ray absorption fine structure analysis reveal that the Eu atoms doped in Ga2O3 matrix are incorporated on Ga sites in Ga2O3 matrix even for the films with amorphous structure grown at low substrate temperature.