Epitaxial growth of germanium-rich silicon-germanium films on Si(001) substrate by reactive thermal chemical vapor deposition

摘要

In this paper, a study on the growth kinetics of Ge-rich Si_(1-x)Ge_x films on Si substrate through a reactive thermal chemical vapor deposition (RTCVD) is conducted using Si_2H_6 and GeF_4 as the source gases. The growth temperature is lower than 400 ℃. The influence of substrate temperature and gas pressure on the microstructure and crystallinity of Si_(1-x)Ge_x epilayer is investigated. By optimizing the growth parameters, high quality epitaxial Si_(1-x)Ge_x layer is fabricated at 350℃, with a threading dislocation density of ～7 × 10~5/cm~2 and surface RMS roughness of 1.44 nm. The results suggest that the epitaxial Si_(1-x)Ge_x films by RTCVD are preferable materials for low-cost electronic devices.