Impact of Sequential N Ion Implantation on Extended Defects and Mg Distribution in Mg Ion‐Implanted GaN
Emi Kano, Jun Uzuhashi, Koki Kobayashi, Kosuke Ishikawa, Kyosuke Sawabe, Tetsuo Narita, Kacper Sierakowski, Michał Boćkowski, Tadakatsu Ohkubo, Tetsu Kachi, Nobuyuki Ikarashi
Abstract
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. The impact of sequential N ion implantation on defects and Mg distribution after postimplantation annealing is investigated. The atomic‐resolution analyses show that, in the Mg ion‐implanted region, the N ion implantation increases the concentration of Mg Ga . It is thus concluded that the Mg soluble in GaN by Mg ion implantation is 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 is suppressed by the N ion implantation: the defects in the Mg+N‐implanted sample are nanoscale interstitial‐type defects, and they do not grow or annihilate after annealing. This indicates that the N implantation changes the concentrations of interstitials.