Direct Measurement of the Inter-Diffusion in Quantum Wells Enhanced by Group V Intermixing for in P-Based Structures

Group V inter-diffusion in InGaAsP/InP quantum wells (QW) has been studied using analytical electron microscopy in the temperature range of 600–850°C. The structure was grown by metalorganic chemical vapour deposition (MOCVD) and subsequently capped with a 100 nm thick layer of SiO2, Si3N4 or low temperature molecular beam epitaxy (MBE)-grown InP (LT-InP). Diffusion coefficients for the group V species were calculated from the width-concentration profiles and activation energies $({\mbi E}_{a})$ together with diffusivity $({\mbi D_{0}})$ were obtained from Arrhenius plots. Small as-grown compositional difference between quantum well and barriers (~6%) in group III prevents us from accurate analysis of In-Ga interdiffusion.