Ge growth over thin SiO2 by UHV-CVD for MOSFET applications

The growth of germanium by ultra high vacuum-chemical vapour deposition (UHV-CVD) on a thin SiO2 layer (0.6 nm) formed on Si(001) was investigated by real-time reflection high energy electron diffraction (RHEED), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). It was observed that the growth of Ge at 600 deg. C on a 2 monolayers thick SiO2 (0.6 nm) film remains perfectly coherent with the Si (001) substrate. The mechanism of reduction of SiO2 is also discussed for higher Ge deposition temperatures. It was found to involve both Si from the substrate and Ge from the gas phase