Epilayers were grown which had a wide range of excess As concentrations and were subjected to various annealing treatments in order to study the role which point defects and As precipitates played in carrier trapping and recombination. Before annealing, the point defects rapidly trapped photo-generated electrons and holes; usually at sub-ps time-scales. However, full electron-hole recombination occurred at a much longer time-scale. After annealing, the full electron-hole recombination lifetime appeared to be greatly reduced, thus indicating that As precipitates played an important role.

A.J.Lochtefeld, M.R.Melloch, J.C.P.Chang, E.S.Harmon: Applied Physics Letters, 1996, 69[10], 1465-7