Hydrogen density-of-states in b-Ga2O3 (Conference Presentation)

In this paper, we present an experimental study of hydrogen (H) and deuterium (D) in single crystal and polycrystalline b-Ga2O3. H or D was introduced into the specimens using ampoule passivation at elevated temperatures. The samples were characterized with infrared absorption and gas effusion measurements. As-grown single crystal b-Ga2O3 contains a residual H concentration of about 1019 cm-3 and exhibits a local vibrational mode at 3437.6 cm-1 that has been attributed to O – H. Polycrystalline b-Ga2O3 thin-films were grown by pulsed laser deposition. Hydrogen effusion measurements show that these samples contain H concentrations of up to about 1020 cm-3. From the hydrogen effusion spectra, the H chemical potential was determined as a function of the H concentration, which can be related to the H density-of-states distribution.