摘要
The effect of thickness of a low-temperature silicon (LT-Si) buffer layer on the growth of SiGe overlayer was investigated. The solid-source molecular beam epitaxy method was used to grow 300-nm-thick Si 0.7 Ge 0.3 films on 50- to 300-nm-thick Lt-Si buffer layers at 450 °C. Transmission electron microscopy, Raman scattering and x-ray rocking curve measurements were used to study the effects of LT-Si buffer layer thickness on the quality of the SiGe layer. It was found that surface roughness was independent of the LT-Si thickness and the threading dislocation density decreases with the thickness of the LT-Si buffer.