Thermal oxidation of InAs and characterization of the oxide film

Abstract The thermal oxidation of InAs and the properties of the resultant oxide films were studied. Uniform InAs oxide films with a resistivity of 1012 Ω cm were obtained on InAs substrates by low temperature oxidation at around 400°C. The thermal oxide films are mainly composed of polycrystalline In2O3 and As2O3. Increasing oxidation temperature causes thermal decomposition of the As2O3 and the accumulation of elemental arsenic in the oxide film. The oxide resistivity decreases with increasing oxidation temperature, mainly as a result of the thermal decomposition of the As2O3. The interface state densities near the midgap of InAs are (2–5) × 1011 cm-2 eV-1. A metamorphic layer is formed beneath the thermal oxide of InAs by high temperature oxidation above 500°C.