Composition dependence of dislocation-mediated strain relaxation in InGaAs/GaAs heteroepitaxy

Recent work has confirmed the accuracy of real-time measurements of the stress-thickness product collected using optical monitoring of the wafer curvature during MBE growth. These experiments yield plots of the strain relieved vs. film thickness, thus providing direct comparison with kinetic models of dislocation-mediated relaxation. The present contribution documents the experimental relaxation profile and its change with growth temperature in the range of approximately 400-500/spl deg/C for two values of In composition, x /spl sim/ 0.15 and x /spl sim/ 0.30.