Abstract
It is the purpose of this investigation to develop the techniques of depositing SiO2, Ta2O5 films on silicon by reactive sputtering. The infrared absorption, the refractive indexes, the dielectric constants, the dielectric breakdown strengths and ultraviolet absorptions of these films indicate that the oxides may be considered as stoichiometric SiO2, Ta2O5. The interface properties of these systems are evaluated mostly by the C-V curves of MOS diodes. The surface state charge density of 120 × 1011/cm2 is measured, they can be decreased by selecting the discharge conditions to minimize the bombardment effects of ions and electrons. C-V curves of MOS diodes with large surface states show frequency dependence. Frequency dependences of these elements are examined experimentally and theoretically. The qualitative agreement between the theoretical and experimental C-V curve is obtained. But these surface states produced by sputtering can be decreased by heat treatments above 700°C.
