HIGH-TEMPERATURE ANNEALING OF SEMIINSULATING GAAS AND THE DISSOCIATION OF EL2

Existing data on the n-p type conversion of semi-insulating GaAs durin g high temperature (1100-1200 degrees C) anneals are fit using a previ ously developed model in which EL2 is identified as the native defect AsGaVGa. In this model EL2 dissociates into the acceptor V-Ga and the donor As-Ga. The latter defect then rapidly captures a divacancy to fo rm the electrically neutral complex AsGaVAsVGa. The decrease in EL2 co ncentration, the n-p type conversion of GaAs, and the subsequent incre ase in hole concentration as the annealing temperature is increased ar e correlated in the model. (C) 1995 American Institute of Physics.