In-plane anisotropy in the direction of the dislocation bending in α-Ga2O3 grown by epitaxial lateral overgrowth

Abstract

Threading dislocations in α-Ga2O3 grown by epitaxial lateral overgrowth (ELO) were observed by using atomic force microscopy after a surface etching using 10 wt% KOH aqueous solution heated at 60 °C. The ELO α-Ga2O3 was characterized by an in-plane anisotropy in the direction of the dislocation bending as followings: the dislocations in ELO α-Ga2O3 bend in the direction of α-Ga2O3, while the dislocation-free areas expand in the direction from the positions of windows. The anisotropy is an important factor to control the dislocations in α-Ga2O3 and to optimize the ELO of α-Ga2O3.