Modeling of Zn diffusion in InP/InGaAs materials during MOVPE growth

Abstract

Simple MOCVD grown InP/InGaAs heterostructures were used in this Zn diffusion study. After each epitaxial step, Zn profiles were measured by SIMS. PROPHET, a process simulation tool, was used to model these experimental results and extract the Zn diffusivities in InP and InGaAs materials. We conclude that Zn diffusion can be explained by the previously reported kick-out mechanism. During the InGaAs epitaxial growth, Zn diffusion is enhanced when the Zn doping level is about 1/spl times/10/sup 19/cm/sup -3/, while no enhanced Zn diffusion occurs when the Zn doping level is 1/spl times/10/sup 18/ cm/sup -3/ or less. We propose that a possible explanation for the enhancement of Zn diffusion during the high Zn-doped InGaAs/InP growth is the creation of the point defects during the growth.