STRAIN EFFECTS ON CARRIER LIFETIMES IN INGAAS (AL)GAAS MULTIPLE-QUANTUM WELLS/

Lifetimes were measured in several InGaAs/(Al)GaAs samples with variou s levels of strain and strain relief, with thick barriers and with GaA s barriers. Lifetimes of the order of 0.5 ns were measured. We have fo und that the introduction of indium, to obtain InGaAs wells, causes a dramatic decrease in the carrier lifetime by an order of magnitude, as compared with similar GaAs wells. Once indium is present in the wells then the dominant carrier loss-recombination process in the InGaAs mu ltiple quantum well materials is unaffected by the strain, strain reli ef or barrier design.