Impact of gate-oxide breakdown of varying hardness on narrow and wide nFET's

The soft gate-oxide breakdown event is observed to have negligible impact on the intrinsic parameters of even a narrow nFET. However, during subsequent wear-out of the breakdown path a significant impact of gate-to-channel breakdowns on nFET characteristics is found. It is also shown that (i) the effect of voltage stress on gate oxide and (ii) apparent electrical effects have to be corrected for to properly understand the intrinsic nature of the breakdown.