【International Papers】Tutorial: Microscopic properties of O–H centers in β-Ga₂O₃ revealed by infrared spectroscopy and theory

      Researchers from the Lehigh University have published a dissertation titled "Tutorial: Microscopic properties of O–H centers in β-Ga₂O₃ revealed by infrared spectroscopy and theory " in Journal of Applied Physics.

Abstract

      β-Ga₂O₃ is an ultrawide bandgap semiconductor that is attracting much attention for applications in next-generation high-power, deep UV, and extreme-environment devices. Hydrogen impurities have been found to have a strong effect on the electrical properties of β-Ga₂O₃. This Tutorial is a survey of what has been learned about O–H centers in β-Ga₂O₃ from their vibrational properties. More than a dozen, O–H centers have been discovered by infrared absorption spectroscopy. Theory predicts defect structures with H trapped at split configurations of a Ga(1) vacancy that are consistent with the isotope and polarization dependence of the O–H vibrational spectra that have been measured by experiment. Furthermore, O–H centers in β-Ga₂O₃ have been found to evolve upon thermal annealing, giving defect reactions that modify conductivity. While much progress has been made toward understanding the microscopic properties and reactions of O–H centers in β-Ga₂O₃, many questions are discussed that remain unanswered. A goal of this Tutorial is to inspire future research that might solve these puzzles.

FIG. 1.Monoclinic structure of β-Ga₂O₃. The color code of inequivalent sites is shown. The nearest neighbor (NN) coordination of the two inequivalent Ga sites and three inequivalent O sites is also shown. These models and others in this paper were constructed using MOLDRAW and POV-ray.

Original link:https://doi.org/10.1063/5.0196386