Study on thermal strain of ZnTe/Si(211) and ZnTe/GaAs(211) heterostructures

The distribution of thermal strain and curvature radius of ZnTe/Si(211) and ZnTe/GaAs(211) heterostructure samples were analyzed by theoretical calculation and laser interferometer measurement at room temperature. The results showed that the strain profiles and curvature radius of ZnTe grew on asymmetry(211) surface, are asymmetric along in-plane direction along1-1-1 and01-1. The laser interference measurement result of the ZnTe/GaAs(211) sample conformed to the theoretical calculation with the radius of curvature, which are the same order of magnitude and both are in negative direction, indicating the tensile strain. But for the ZnTe/Si(211) sample, the measurement result showed much difference. The plastic deformation was formed during the high temperature deoxidation process of Si substrate, which produced heterostructure bending with positive radius of curvature. The plastic deformation of Si substrate reduced the bending degree of ZnTe/Si(211) heterostructure, so the thermal mismatch strain was also reduced.