Effects of Substrate Misorientation Direction on Strain Relaxation at InGaAs/GaAs(001) Interfaces

Abstract

ABSTRACTWe have investigated the effects of substrate misorientation direction on strain relaxation at InGaAs/GaAs(001) interfaces. Calculations of the shear stresses due to the misfit strain, resolved on the glide plane in the glide direction, suggest that the dislocation glide force and the activation energy for dislocation nucleation are essentially identical for the α and β slip systems. However, experimental results indicate that asymmetries in strain relaxation are sensitive to A-type misorientation and/or step-edge densities. Thus, a dislocation nucleation source or glide velocities sensitive to step densities or local roughness may explain these results.