Impact of sequential N ion implantation on extended defects and Mg distribution in Mg ion‐implanted GaN

In Mg ion implantation doping of GaN, sequential N ion implantation reportedly changes Mg concentrations in the Mg ion‐implanted region and the underlying region after activation annealing. We investigated the impact of sequential N ion implantation on defects and Mg distribution after post‐implantation annealing. Our atomic‐resolution analyses showed that, in the Mg ion‐implanted region, the N ion implantation increases the concentration of MgGa. We thus conclude that the Mg soluble in GaN by Mg ion implantation was increased by N ion implantation. The rest of the Mg atoms agglomerate to form clusters on the extended defects, and their concentration is also increased by the N implantation. The coarsening of extended defects was suppressed by the N ion implantation: the defects in the Mg+N implanted sample were nano‐scale interstitial‐type defects, and they did not grow or annihilate after annealing. This indicates that the N implantation changed the concentrations of interstitials.This article is protected by copyright. All rights reserved.