The formation of SiO2 films on silicon by high dose oxygen ion implantation

High dose oxygen ion implantation into silicon at 30 keV was performed to produce SiO2 surface layers. The oxygen profile, stoichiometry and volume swelling were studied by Rutherford backscattering at doses of up to 2 x 1018 cm-2 and for various current densities. The surface structure and lateral homogeneity of the insulation properties were investigated by scanning electron microscopy and the liquid crystal technique respectively. By means of current-voltage and capacitance-voltage measurements the electrical properties of the layers produced were determined. A qualitative model of the formation of SiO2 during high dose oxygen implantation into silicon is proposed. Blistering caused by implantation at high current densities leads to oxygen losses and to conductive channels in the dielectric layer. Except for their interface properties the SiO2 films produced are comparable with thermal oxides. (Auth.)