Field dependent critical trap density for thin gate oxide breakdown

We have found that the total trapped negative charge in a thin gate-oxide at the point of breakdown is a strong function of the stress field. This observation is in direct contrast with previous reports in the literature. The field dependent behavior of total trapped charge leads to the conclusion that the critical trap density for breakdown is also field dependent. We use field dependent hopping conduction to explain why the critical trap density for breakdown in the percolation model should be field dependent.