Correlation between two time-dependent dielectric breakdown measurements for the gate oxides damaged by plasma processing

The relationship between two time-dependent dielectric breakdown (TDDB), the charge-to-breakdown under constant-current injection (Q_bd), and the time-to-breakdown under constant-voltage stress (t_bd) is derived from a defect generation model and investigated for the gate oxide damaged by plasma processing such as the antenna effect. It is found that although the Q_bd of the damaged oxide monotonously decreases with antenna ratio (r=exposed antenna surface area/gate area), the t_bd does not apparently decrease in a certain antenna ratio region. The difference between the degradation rate of Q_bd and t_bd along r is explained by taking into account the r- and time dependence of gate current density under constant-voltage stress J and the rand J-dependence of Q_bd