A threshold voltage expression for small-size MOSFET´s based on an approximate three-dimensional analysis

A simple threshold voltage expression based on an approximate three-dimensional analysis has been obtained for MOSFET´s with the LOCOS isolation structure. It predicts both the short-channel and the narrow-width effects on the threshold voltage of MOSFET´s, and the results match the experimental data. In addition, the threshold expression is more general than any other existing models. It includes all the relevant device parameters, such as the drain voltage, the oxide and surface charges, and the fringe field through the oxide sidewalls.