Growth and physical characterization of high resistivityFe: β-Ga₂O₃ crystals

High quality 0.02 mol%, 0.05 mol%, and 0.08 mol% Fe:β-Ga₂O₃ single crystals were grown by the floating zone method. The crystal structure, optical, electrical, and thermal properties were measured and discussed. Fe:β-Ga₂O₃ single crystals showed transmittance of higher than 80% in the near infrared region. With the increase of the Fe doping concentration, the optical bandgaps reduced and room temperature resistivity increased. The resistivity of 0.08 mol% Fe:β-Ga₂O₃ crystal reached to 3.63×10¹¹ Ω·cm. The high resistivity Fe:β-Ga₂O₃ single crystals could be applied as the substrate for the high-power field effect transistors (FETs).