Characterization of Vacancy-Type Defects in Mg- and N-Implanted GaN by using a Monoenergetic Positron Beam

Gallium nitride (GaN) is one of the key materials for post-Si-based power electronics. At present, almost all commercial GaN-based devices are fabricated using lateral architecture. However, high-performance vertical GaN diodes and transistors have been studied extensively [1]–[4]. Here, optimization of the device processing is key for commercializing vertical devices. One of the critical building blocks for these devices is the selective area doping of impurities. Precisely controlled impurity concentrations and their profiles can be achieved using only ion implantation. The major drawback of ion implantation is the generation of point defects due to atomic collisions [5]. Such defects could relate to the low activation rate of implanted impurities, the degradation of electric properties, and the reliability of devices.