Epitaxial growth of germanium-rich silicon–germanium films on Si(0 0 1) substrate by reactive thermal chemical vapor deposition

Abstract

In this paper, a study on the growth kinetics of Ge-rich Si1−xGex films on Si substrate through a reactive thermal chemical vapor deposition (RTCVD) is conducted using Si2H6 and GeF4 as the source gases. The growth temperature is lower than 400°C. The influence of substrate temperature and gas pressure on the microstructure and crystallinity of Si1−xGex epilayer is investigated. By optimizing the growth parameters, high quality epitaxial Si1−xGex layer is fabricated at 350°C, with a threading dislocation density of ∼7×105/cm2 and surface RMS roughness of 1.44nm. The results suggest that the epitaxial Si1−xGex films by RTCVD are preferable materials for low-cost electronic devices.