Dielectric breakdown caused by hole-induced-defect films

The dielectric breakdown induced by substrate hot-hoE injection has been investigated using p-channel MOSFETs with the gate oxide of the thickness ranging from 60 to 120 A and it has been revealed that the breakdown is induced by hole injection from the Si substrate even at low oxide fields. The positive charge to breakdown (Q,) calculated from integrating the hole current is independent of the oxide field, but decreases rapidly with decreasing the oxide thickness. Also, it has been shown that the positive charges in SiO, film induced by hole injection are removed by the annealing at 25O”C, while the hole trap centers are not disappeared. This suggests that the dielectric breakdown occurs at a weak oxide spot, which can capture the positive charges.