Structural disorder and distribution of impurity atoms in β-Ga2O3 under boron ion implantation

Abstract

Gallium oxide (Ga2O3) has recently attracted much attention due to the prospect of its application in power electronics and in other areas. An important task is the development of controlled and reproducible methods for doping this material with various impurities, among which boron is of considerable interest. The regularities of Ga2O3 doping with this isovalent (for Ga) impurity are poorly studied. Even for ion implantation as the most common semiconductor doping method these studies are still at the initial stage. In this work, the structural properties of β-Ga2O3 layers upon boron ion irradiation and subsequent annealing have been studied using X-ray Diffraction, Reflection High-Energy Electron Diffraction, Secondary Ion Mass Spectrometry, as well as theoretical calculations from first principles. Among the most interesting results are the establishment of a strong redistribution of implanted boron during post-implantation annealing and the conclusion about low degree of substitution of gallium sites by boron atoms.