Modeling of the Hole Current Caused by Fowler-Nordheim Tunneling through Thin Oxides

A new model for the substrate hole current that occurs during Fowler-Nordheim (FN) stress of thin oxides is proposed. The model is based on the assumption that hot hole injection occurs at the anode. The probability that a hole is emitted in the oxide and contributes to the hole current is described by an empirical relation that is a function of the effective barrier height and the average energy of the electrons arriving at the anode. To compute the average electron energy in the oxide, an energy dependent energy relaxation distance is used. The results obtained with the model are in very good agreement with the measurements for oxides within a thickness range of 5.5 to 12.5 nm.