Evolution of the Si-SiO2 interface trap characteristics with Fowler-Nordheim injection

Using a recently proposed method based on charge pumping measurements which allows the extraction of the Si-SiO2 interface trap depth concentration profiles, the trap parameters are studied as a function of Fowler-Nordheim injection. As the stress proceeds, the interface trap layer extends deeper in the direction of the oxide depth, the trap density in the oxide seems to increases faster than that at the interface and the trap capture cross sections strongly increase. This induces a deeper penetration of the carriers into the oxide depth and a larger contribution of the so called slow traps to the electrical properties of the devices. This can be viewed as an extension of the Si-SiO2 interface in the direction of the oxide depth.