High germanium content strained SGOI by oxidation of amorphous SiGe film on SOI substrates

We report the fabrication of single-crystalline Si0.4Ge0.6-on-insulator by oxidizing cosputtered amorphous SiGe film on silicononinsulator (SOI) substrates. After a two-step oxidation process, thin Si0.4Ge0.6-on-insulator (SGOI) film with a uniform Ge concentration has been achieved. Various defects were observed during condensation. Crystalline properties of the SGOI layers are investigated by micro-Raman technique. The anisotropy of the strain in the Si0.4Ge0.6 film is deconvoluted by high-resolution X-ray diffraction measurements and the estimated Ge content closely matches with energy dispersive X-ray analysis in cross-sectional transmission electron microscopy. The overall strain in these SGOI films is beneficial for the improvement of hole mobility of the metal-oxide-semiconductor field effect transistors. A cyclic annealing step is found to be effective for improving the film quality of Si0.4Ge0.6-on-insulator. Such a cost-effective and simple method is promising for fabricating high Ge-content strained SiGe-on-insulator and pure Ge-on-insulator structures for high mobility device applications. (c) 2005 The Electrochemical Society.