High quality partially relaxed SiGe film grown on silicon-on-insulator substrate by ultra-high vacuum chemical vapor deposition

Strain-relaxed SiGe film is grown on a silicon-on-insulator (SOI) substrate by an ultrahigh vacuum chemical vapor deposition system (UHVCVD). Rutherford backscattering spectroscopy together with channeling demonstrates that the SiGe film grown on the SOI substrate is of high crystalline quality without significant dislocations. Cross-sectional TEM images of the Si/SiGe/SOI sample also indicate that there are no dislocations within the SiGe layer. The status of strain in both the Si cap layer and its underlying SiGe layer are evaluated by high-resolution x-ray diffraction (HRXRD) and Raman spectroscopy, respectively. 0.36% of tensile strain in the Si cap layer is exhibited in the HRXRD rocking curve. Raman spectroscopy measurements show that the relaxation degree of strain in the SiGe film grown on the SOI substrate is 24%.