Time-resolved reflectivity measurement of thermally stabilized low temperature grown GaAs doped with beryllium

Abstract

The influence of Be-doping on carrier lifetime in low temperature grown (LT) GaAs has been studied using time-resolved reflectivity measurement. The ultrafast photogenerated carrier lifetime decreases with increasing Be doping concentration, because the total amount of excess As, i.e., arsenic antisites (As/sub Ga/), and the ionized arsenic antisites are increased due to mechanical and electrical compensation between As/sub Ga/, and Be acceptor. It was observed that the carrier lifetime in Be-doped LT-GaAs can be even shorter after high temperature annealing, which is contrary to the behavior of undoped samples.