Existing data on the n-p conversion of semi-insulating material during high-temperature (1100 to 1200C) annealing were fitted by using a previously developed model in which EL2 was identified as being the native defect, AsGaVGa. In this model, EL2 was suggested to dissociate into the acceptor, VGa, and the donor, AsGa. The latter defect then rapidly captured a di-vacancy so as to form the electrically neutral complex: AsGaVAsVGa. A decrease in EL2 concentration, an n-p conversion, and the subsequent increase in hole concentration, as the annealing temperature increased, were correlated by the model.

R.A.Morrow: Journal of Applied Physics, 1995, 78[8], 5166-7