The effect of O2 plasma on properties of the SiSiO2 system

Abstract

The radiation damage in a Si-SiO2 system exposed to O2 plasma in a planar reactor is investigated in dependence on the exposure time, the substrate temperature, and the pressure of O2. Capacitance-voltage (C-U) techniques and a static method are used to monitor charge trapping in the metal-oxide-semiconductor (MOS) capacitors. In all experiments a negative and a positive charging effect is observed as a result of plasma influence. Low and high temperature annealing is performed in order to eliminate radiation damage induced by the plasma. It is concluded that high temperature annealing is necessary prior to metallization to remove completely the radiation damage produced at substrate temperatures sufficiently above 20 °C. Metallized Si-SiO2 systems are also investigated and it is found that the metal layer gives a complete protection against the influence of the plasma.