Low-Temperature, Low-Pressure Chemical Vapor Deposition and Solid Phase Crystallization of Silicon-Germanium Films

Low-pressure chemical vapor deposition of silicon–germanium Si1−xGex and its SPC below 400°C are investigated. The effects of precursor ratio SiH4/SiH2Cl2 DCS :GeH4 , pressure, and temperature are examined with the goals of film composition tunability and high deposition rates. SiH4 is found to be a better source gas than DCS because the decomposition rate of SiH4 is faster than that of DCS during the deposition process. In the SiH4:GeH4 system, the binary deposition mechanism is well explained by the “enhancement” model. The deposition temperature and chamber pressure affect the conversion factor, enabling independent tuning of the film composition and deposition rate. Amorphous Si0.7Ge0.3 and Si0.5Ge0.5 films are obtained at 350 and 400°C by adjusting the deposition conditions while keeping the deposition rates high. Compositional effects of the SiGe films on the SPC are also investigated. © 2008 The Electrochemical Society. DOI: 10.1149/1.3008009 All rights reserved.