Study and characterization of the nanotextured Ga2O3-GaOOH formations synthesized via thermal oxidation of GaAs in ambient air

Abstract

In this work, we present the characterization of a UV-sensitive material based on Ga2O3-GaOOH, which was obtained through the thermal oxidation of GaAs wafers in ambient air to achieve Ga2O3. The material’s oxidation mechanism was thoroughly examined using structural, compositional, and optical approaches. X-ray diffraction analysis identified the presence of the β-Ga2O3 crystalline phase, with both in-plane and out-of-plane preferred orientations, along with crystalline inclusions attributed to GaOOH. Furthermore, energy-dispersive spectroscopy confirmed the uniform sublimation of Arsenic, as evidenced by elemental mapping, while Fourier-transform infrared spectroscopy suggested the inclusion of −OH bonds. Surface analysis was carried out by field emission scanning electron microscopy and atomic force microscopy, revealing a grain size of approximately 20 nm. Finally, UV-Vis characterization unveiled a bandgap ranging from 2.9 to 3.9 eV, indicative of the material’s potential for UV-sensitive applications. Overall, the results demonstrate the consistency and reliability of the oxidation process, providing valuable insights into the properties of the Ga2O3-GaOOH material for potential technological advancements.