New IGFET short-channel threshold voltage model

A simple closed form expression for the threshold voltage VTof non-uniformly doped short-channel IGFET\´s is derived by solving two-dimensional Poisson equation over the depletion region under the gate using a step doping profile approximation. An exponential dependence on channel-length L and a linear dependence on drain-to-source voltage VDSand substrate bias VBSare predicted for , the reduction in short-channel threshold voltage. These predictions are in close agreement with measured VTcharactersistics of submicron IGFET\´s.