Point defects in gamma-irradiated n-GaN

Abstract

Radiation-induced point defects and their annealing in silicon-doped n-GaN have been investigated by means of Hall effect measurements and Raman spectroscopy. Correlated compensation effects due to simultaneous introduction of donor and acceptor centres are observed in irradiated n-GaN. The defect production rate is dependent on the dopant concentration. This means that the model of all native defects immobile at room temperature is not true. The behaviour of radiation-induced defects upon heating is complicated, exhibiting two prominent stages of reverse annealing. The presence of radiation defects is still observable after annealing to T= 750 °C.