Cathodoluminescence study of the influence of misfit dislocations on hole accumulation in an n-AlGaAs/p-GaAs/n-InGaAs heterojunction phototransistor
نویسندگان
چکیده
We have studied the influence of misfit dislocations on hole accumulation in the base layer of an n-AlGaAs/p-GaAs/n-InGaAs heterojunction phototransistor ~HPT!. Spatially and temporally resolved cathodoluminescence ~CL! measurements reveal that variations in the hole accumulation is caused primarily by strain-induced defects which impede the transport of holes in the collector. The lifetime of holes in the InGaAs/GaAs collector is found to be negligibly affected by the underlying misfit dislocations in the InGaAs/GaAs collector. The reduction in the local electron-beam-induced current signal by the dislocations is less than ;20%, indicating that these defects have a minor impact on the overall device performance. © 1996 American Institute of Physics. @S0003-6951~96!00937-0#
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