Local strain in Si/Si 0.6Ge 0.4/Si(100) heterostructures by stripe-shape patterning

Abstract

In Si/Si 0.6Ge 0.4/Si(100) heterostructure patterned into stripe shape, local strain in the capping Si and Si 0.6Ge 0.4 layers was investigated. From the strain amount evaluation by Raman scattering spectroscopy using visible and ultraviolet light, relationship between the strain relaxation amount in the strained Si 0.6Ge 0.4 layer and tensile strain amount in the capping Si layer was clarified. The Raman shift change in the 5 nm-thick capping Si layer was in excellent agreement with the expected value with assumption of perfect in-plane lattice matching between the Si 0.6Ge 0.4 and capping Si layers. In the case of the thicker capping Si layer, the Raman shift change tends to be smaller than that for the 5 nm-thick capping Si layer.