High rate growth of In2O3 at 1000 °C by halide vapor phase epitaxy

Abstract

In this work, the first-ever growth of cubic-In2O3 at 1000 °C by halide vapor phase epitaxy (HVPE) was achieved, using gaseous InCl and O2 as precursors in a N2 flow. The growth rates of In2O3 layers on (001) β-Ga2O3 and (0001) sapphire substrates were 4.1 and 5.1 µm/h, respectively, even at the high growth temperature applied, which are approximately half the growth rate of β-Ga2O3 homoepitaxially grown by HVPE at 1000 °C. Theoretical thermodynamic analyses were also conducted, and results confirmed the growth of In2O3 at temperatures above 1000 °C by HVPE. The as-grown In2O3 layers were light yellow-green in color. The In2O3 layers grown on the (001) β-Ga2O3 and (0001) sapphire substrates exhibited an optical absorption edge at about 370 nm, in addition to n-type conductivity with electron concentrations of 2.7 × 1018 and 1.7 × 1018 cm−3, and electron mobilities of 16.2 and 22.7 cm2 V−1 s−1, respectively.