[Influence of strain in the Si cap layer of Si/SiGe heterostructure on its Raman spectra].

Strained Si/SiGe heterostructure was prepared by high dose Ge ion implantation and a subsequent high temperature rapid thermal processing method. A 325 nm UV laser was used to analyze the Raman spectra of the strained Si cap layer. It was found that tensile strain in the Si cap layer can induce a shift toward lower frequency of the first order Raman scattering peak of 520 cm(-1). In light of the variation of peak position, a lateral tensile stress of 12.5 x 10(8) N x m(-2) in Si cap layer was worked out. However, the tensile strain in the Si cap layer can not lead to a variation of the sub-order Raman scattering peaks around 1 555 and 2 330 cm(-1).