Auger recombination in heavily carbon-doped GaAs

The recombination parameters in heavily carbon-doped GaAs are of considerable importance to current bipolar transistor technology. Here, we used time-resolved photoluminescence and quantum-efficiency techniques in parallel to measure the very short lifetimes expected at high doping. The samples were isotype double heterostructures, with the structure Al(0.4)Ga(0.6)As/GaAs/Al(0.4)Ga(0.6)As, grown by molecular-beam epitaxy. The doping level was varied from 5x10(18) to 1x10(20) cm(-3) for the samples described here. For doping levels greater than 1x10(19) cm(-3), the lifetime decreased as the inverse of the cube of the hole density, indicating that phonon and impurity-assisted Auger processes are dominant. (C) 2001 American Institute of Physics.