Thermal instability of InGaAs/InGaAsP quantum wells

The effects of high temperatures required for the growth of further layers on InGaAs quantum wells with InGaAsP barriers are discussed. Measurement results indicate that quantum wells consisting of InGaAs with InGaAsP barriers are unstable at typical metalorganic chemical vapor deposition (MOCVD) growth temperatures. Diffusion of all four constituents across the interface produces a blue shift in the photoluminescence (PL) peak. The effect is explained by a simple diffusion model. It is shown that, to match the experimental data, it is necessary to assume that a thin graded region was already formed before the start of the annealing experiments