A theory of enhanced impact ionization due to the gate field and mobility degradation in the inversion layer of MOSFET´s

A new explanation of carrier heating within silicon inversion layers is offered which is in full accordance with classical laws. We show that, as is usually assumed, the heating is due to the longitudinal electric field. However, also the transverse field influences the electron temperature by determining the minimum kinetic energy and therefore influencing the electron mobility. In this way the distribution function is heated above that in bulk material as witnessed by the significant increase in measured noise figures and in the calculated electron impact ionization rate.