GE COMPOSITION AND TEMPERATURE-DEPENDENCE OF THE DEPOSITION OF SIGE LAYERS

SiH4 and GeH4 deposition of Si1-xGex layers by a rapid thermal process very low pressure chemical vapor deposition method has been studied in this paper. The Ge incorporation rate increases to a maximum value and then decreases as temperature increases. The growth rate of the SiGe alloy reaches its maximum value and then decreases as Ge composition increases. Ge incorporation also enhances the Si deposition rate in the Si1-xGex alloy. These results have been explained by increasing the hydrogen desorption rate at low temperatures and low value of x (the germanium concentration) and decreasing the adsorption probability of reactive hydrides at high temperature and high value of x.