An investigation was made of the structural and electronic properties and formation energies of vacancy, interstitial and antisite defects, as well as of complex formation in wurtzite InN using first-principles calculations. The N interstitial, which formed a split-interstitial configuration with N2-like bonding, had the lowest formation energy under N-rich conditions in p-type material, where it was a triple donor. It was found that indium vacancies had a tendency to form so-called clusters, which resulted in local nitrogen-rich regions and the formation of Nx-molecular-like bonds. These complexes were amphoteric, had a relatively high formation energy and formed more readily under N-rich conditions. The nitrogen vacancy was a low-energy defect under more In-rich conditions and, in p-type material acted as a single and triple donor. In the neutral and negative charge states, nitrogen vacancies preferred to be situated close to one another and to cluster; giving rise to local In-rich regions with electron localization at these metallic-like bonding configurations. The indium antisite in the 4+ charge state was the lowest-energy defect under In-rich conditions in p-type material and also acted as a donor.

Vacancies and Interstitials in Indium Nitride - Vacancy Clustering and Molecular Bond-Like Formation from First Principles. X.M.Duan, C.Stampfl: Physical Review B, 2009, 79[17], 174202