Ti Surface Oxidization by Microwave Discharge Oxygen Plasma and Plasma Parameters

We made an experimental study on Ti surface oxidization by microwave discharge oxygen plasma, which was generated in a cylindrical quartz tube (26 mm id.) with its discharge pressure 0.5 - 10.0 Torr. The microwave frequency was 2.45 GHz and the output power was set at 600 W. The gas flow rate was set at about 0.01 -- 1.6 l/min. The titanium sheet (15 $\times $15$\times $0.2 mm$^{3})$ was set at the position 60 mm down from the centerline of the microwave guide. The treatment time was 1 hour. We measured basic parameters of microwave oxygen plasma, such as electron density ($N_{e})$, electron temprature ($T_{e})$ by a double probe, vibrational and rotational temperatures ($T_{v}$, $T_{r})$ by OES. It was found that the $N_{e }\sim $ 10$^{11 }$cm$^{-3}$,$ T_{e }\sim $ 5 eV, $T_{r }\sim $ 0.14 eV and $T_{v} \quad \sim $ 0.25 eV, respectively, at a low discharge pressure. Only the rutile pattern was found for the samples by XRD. We are examining the effect of admixture of noble gases with oxygen.