3-1-1 Yagumo-nakamachi, Moriguchi, Osaka 570 JAPAN AESTRACT The leakage current induced by the plasma charging damage in ultra-thin gate oxide is characterized from the time dependence of leakage current under constant-voltage stress for both stress-polarities. Based on the electron trapping model, the trap site density generated by the plasma processing is calculated. It is found that an annealing process recovers dominantly the plasma process-induced traps in the oxide, rather than the Si/Si02 interface states.