Positron lifetime investigations were made of a series of samples which had been irradiated with 2.5MeV electrons to various doses. In the case of n-type material, positron lifetimes of 265 and 338ps were attributed to In-vacancy plus interstitial complexes and di-vacancy plus interstitial complexes, respectively. These defects were not observed in the case of p-type material. Annealing of both defect types occurred at up to 200C. The introduction rates were estimated to be equal to 0.1/cm for In-vacancy plus interstitial complexes, and equal to about 0.05/cm for di-vacancy plus interstitial complexes. The di-vacancies had a temperature-dependent trapping rate, thus suggesting the involvement of a thermally activated process. No evidence for VP vacancies were found in p-type or n-type material.

T.Bretagnon, S.Dannefaer, D.Kerr: Journal of Applied Physics, 1997, 81[8], 3446-52