Low effective surface recombination in In(Ga)As/GaAs quantum dot diodes

Abstract

Size dependent current-voltage measurements were performed on InGaAs quantum dot active region mesa diodes and the surface recombination velocity was extracted from current density versus perimeter/area plots using a diffusion model. An effective surface recombination value of 5.5 x 10(4) cm/s was obtained that can be reduced by more than an order of magnitude by selective oxidation of Al(0.9)Ga(0.1)As cladding layers. The values are three times smaller than those obtained for a single quantum well. The effect of p-type doping in the active region was investigated and found to increase the effective surface recombination. (C) 2011 American Institute of Physics. [doi:10.1063/1.3611387]