Atmospheric-Pressure Plasma Oxidation Process for Passivation of Si Surface

Surface passivation films on Si wafers have been prepared by atmospheric-pressure (AP) plasma oxidation technique. Optical emission spectroscopy of O$_{2}$/He AP plasma revealed that SiO$_{2}$ films were obtained at high oxidation rate under the condition with high O emission intensity. From the MOS CV measurements of obtained SiO$_{2}$/Si interface, the interface state density ($D_{it})$ and the fixed oxide charge density ($Q_{f})$ were in the range of (4--20) $\times $ 10$^{10}$ cm$^{-2}$eV$^{-1}$ and (5--20) $\times $ 10$^{11}$ cm$^{-2}$, respectively. According to the model calculation on surface recombination velocity ($S)$ demonstrated that the obtained $Q_{f}$ was sufficient to significantly reduce $S$ for n-type Si with SiO$_{2}$ layer prepared by AP plasma oxidation.