Co‐implantation of Mn + N into p‐type GaN for high <i> T _C </i> ferromagnetism

N and Mn ions were co-implanted into p-type GaN and subsequently annealed at 700–900 °C. The ferromagnetic property was obtained after annealing at 800 °C. As compared with conventional Mn-implanted samples, Mn–N binary phases significantly decreased, resulting in the reduction of the N vacancies. From synchrotron radiation photoemission spectroscopy, the Ga–Mn magnetic phases, which contributed to the ferromagnetic property, were still observed after annealing at 900 °C. From these results, we propose the co-implantation of N and Mn atoms to achieve high TC ferromagnetism in GaN.