Effect of Si Interlayers on Stress and Curvature Radius of GaAs/Si and GaAs/Si/GaAs/Si Heterostructures with Interfacial Misfit Dislocations

Abstract

A theoretical model is proposed to calculate the stress distribution in multilayer heterostructures perturbed by introduction of interfacial misfit dislocations and thermal stress. In this model, the stress relaxation effect caused by interfacial misfit dislocations is considered to spread all over the layers above the heterointerface. Using this model, the stress and curvature radius at 25° C are calculated for the GaAs/Si and GaAs/Si/GaAs/Si heterostructures with interfacial misfit dislocations. The stress shared in the GaAs layer becomes smaller when Si interlayers are inserted into the GaAs layer of the GaAs/Si heterostructure. The curvature radius of the GaAs/Si/GaAs/Si (GaAs/Si with Si interlayers) heterostructure increases as the thickness of the Si interlayer increases. The GaAs/Si heterostructure becomes flat more easily upon insertion of Si interlayers into the GaAs layer.