Investigation on gallium nitride with N-vacancy defect nano-grinding by molecular dynamics

Abstract N-vacancy is an inevitable common point defect in GaN, but its behavior is still unclear during nano-grinding which is an indispensable process technique during some GaN devices manufacturing. In this study, we attempted to explore GaN with N-vacancy during nano-grinding from the perspective of molecular dynamics. The nano-grinding model of GaN with the N-vacancy concentrations from 0 at.% to 5 at.% was considered. The lattice disorder, phase transition, dislocation, grinding force, and temperature were analyzed. The results indicated that N-vacancy changed the behavior of lattice disorder, and created the potential well during the nano-grinding. By the analysis of the dislocation extraction algorithm (DXA), the inhibitory action on dislocation proliferation was observed, and the phase transition from the wurtzite to the zincblende reduced with the increase of the concentration of N-vacancy in GaN. Through the statistical analysis, it was found that N-vacancy also alleviated the grinding force fluctuation and increased the temperature during nano-grinding, which might imply that N-vacancy might improve the processing.