A non-quasistatic MOSFET model for SPICE

An analytic non-quasistatic(NQS) MOSFET model has been derived and implemented in SPICE. It is based on an approximate solution to the non-linear transient current continuity equation in the channel. The model includes the large signal transient and the small signal frequency response analyses. Comparisons have been made between this model and the 1-D numerical solution to the current continuity equation, 2-D device simulation(PISCES) and the quasistatic(QS) results. The channel charge partitioning scheme in the charge based model is shown to be inadequate for the fast transient and the high frequency AC analysis. This model does not use a charge partitioning scheme and the currents are dependent on the history of the terminal voltages, not just the instantaneous voltages and their derivatives.