Current and C-V instabilities in SiO₂ at high fields

Results have been obtained concerning the interrelation of current and C-V instabilities in MOS capacitors subjected to negative gate high-field pulsing. Rising current transients and negative C-V shifts both show the formation of positive charge in the oxide. However, this charge appears to be situated close to the electrodes rather than in the bulk of the oxide and the temperature dependence of the rate of charge accumulation near the electrodes is different for the aluminum and silicon electrodes. These results indicate that the current instabilities and C-V shifts appear to result from independent mechanisms.