Hexagonal-to-Cubic Phase Transformation in GaN Nanowires by Ga+-Implantation

TL;DR

This study investigates the phase transformation from hexagonal to cubic in GaN nanowires induced by Ga+ ion implantation, using optical and structural analyses to understand the underlying mechanisms.

Contribution

It presents new insights into phase transformation mechanisms in GaN nanowires caused by focused ion beam Ga+ implantation, combining optical and electron microscopy techniques.

Findings

Confirmation of phase transformation via optical and structural studies

Potential stabilization of cubic phase due to Ga accumulation or defect dynamics

Insights into irradiation-induced phase stability in GaN nanowires

Abstract

Hexagonal to cubic phase transformation is studied in focused ion beam assisted Ga+-implanted GaN nanowires. Optical photoluminescence and cathodoluminescence studies along with high-resolution transmission electron microscopic structural studies are performed to confirm the phase transformation. In one possibility, sufficient accumulation of Ga from the implanted source might have reduced the surface energy and simultaneously stabilized the cubic phase. Other potential reason may be that the fluctuations in the short-range order induced by enhanced dynamic annealing (defect annihilation) with the irradiation process stabilize the cubic phase and cause the phase transformation.