Dynamics of surface charge region of thin insulator N-type MOS structures

A simple model that relates the dynamics of the surface charge region of a thin insulator N-type metal-oxide-semiconductor (MOS) structure to Fowler-Nordheim tunnelling injection is presented. The main effect of Fowler-Nordheim tunnelling injection on the MOS capacitance-time curves is that the capacitance in the heavy inversion region approaches the low frequency value as the gate voltage is increased. Two relaxation stags and two basic mechanisms responsible for the time-dependent capacitance under Fowler-Nordheim tunnelling injection are described. The model developed from the surface charge relaxation is shown to agree with the experimental data over a wide range of applied electric fields.