Temporary and spatially resolved luminescence studies of p-GaN segments fabricated by vacancy-guided redistribution of Mg using sequential ion implantation of Mg and N

For realizing high-performance GaN power-switching devices, establishing an ion-implantation (I/I) technique to control conductivity type and conductivity in designated segments of GaN is an urgent issue. However, fabricating p-type GaN by Mg doping, especially p-GaN:Mg formation by I/I, has long been a tough job. The difficulty in Mg I/I arises from the fact that high concentration (>10 ¹⁹ cm ^-3 ) divacancies comprising a Ga vacancy (V Ga ) and a nitrogen vacancy (V N ), namely V Ga V N , or trivacancies [V Ga (V N ) 2 ] are introduced by Mg I/I and they agglomerate into (V Ga V N ) 3 clusters by a post-implantation annealing (PIA) [1]. Because such vacancy complexes have been assigned as deleterious nonradiative recombination centers (NRCs) [2], gross amount of vacancies should be minimized and therefore suppressing gross I/I-induced damage is indispensable.