Contributions of Surface States to Mos Impedance

The broad time constant dispersion of states at the Si-SiO2 interface can be explained by the tunneling model introduced by F. P. Heiman and G. Warfield.1 The spectrum of time constants is caused by the exponential decay of the effective capture cross section for larger tunneling distances. A good agreement between theory and experiments was obtained for the oxide traps concentrated within about 10 Å from the interface.