Vacancy effects on plasma-induced damage to n-type GaN

Abstract

Two modes of plasma-induced damage to n-type GaN have been identified, giving rise to contrasting changes to the transport properties. The formation of VGa-ON complexes introduces a deep level in the band gap, while V N give rise to a shallow level in n-GaN. We suggest that when VGa are present in abundance in the bulk, vacancy-complex formation becomes the dominant mechanism of plasma damage that results in an increased resistivity. In the absence of VGa, VN created by the plasma process dominates in creating an enhanced surface conductivity region.