AN ION-BEAM VAPOR-DEPOSITION TECHNIQUE FOR EPITAXIAL-GROWTH OF SI-GE FILMS ON SI SUBSTRATES

We are reporting a new ion beam vapor deposition technique for epitaxi al growth of Si-Ge alloys on [100] Si substrates at temperatures as lo w as 285 degrees C. The growth of Si films involves beam assisted diss ociation of SiH4 gas while the incorporation of Ge is achieved through thermal evaporation of elemental Ge. We have used transmission electr on microscopy, electron diffraction analysis and Rutherford backscatte ring to study the quality of the grown films. The results of this stud y show that a beam energy of 40 to 50 eV yields optimum growth. (C) 19 96 American Vacuum Society.