Comparison of the sidewall recombination in dry and wet etched InGaAs/InP wires

We have investigated the influence of the sidewall recombination on the photoluminescence intensity of wet and dry etched InGaAs/InP wires with widths between 60 nm and 10 μm for a wide range of excitation densities. While we obtain a large sidewall recombination velocity in the range of 107 cm/sec at low excitation density, the decay of the emission intensity with decreasing wire width is completely suppressed at higher excitation density due to the saturation of nonradiative recombination centers. Varying the bias voltage of the dry etching process from 80 V up to 300 V we observe a significant increase of the sidewall recombination of dry etched structures at ion energies above 200 eV. © 1993.