ION-BEAM-ASSISTED DEPOSITION OF SI-CARBIDE FILMS

This paper reports efforts to achieve low-temperature synthesis of SI- C films by ion beam sputtering in a reactive gas with concurrent ion i rradiation. Two argon ion beams were employed, with one sputtering a s ilicon target to provide a Si flux, and the other bombarding the Si or graphite substrate on which films grow. Pure methane gas was introduc ed into the system with a partial pressure up to 1.8 x 10(-2) Pa. The energy of the sputtering beam was around 1 keV, whilst the bombarding beam energies were altered from 0 to 500 eV. By using Rutherford backs cattering spectroscopy and X-ray diffraction, it was shown that films were produced in the amorphous state with a range of C/Si ratios cover ing the stoichiometric composition. X-ray photoelectron spectroscopy a nalysis showed a binding energy shift caused by ion beam bombardment. The discussion focusses on the dependence of the film composition on t he deposition conditions, and the effects of ion bombardment and metha ne partial pressure on the sticking probability via a surface reaction between methane molecules, silicon atoms and bombarding ions.