Simple quasi-two-dimensional analytical model to characterise the electric field in an LDD MOSFET

A simple analytical model for the lateral electric field in the drain region is developed for an LDD MOSFET. A quasi-two-dimensional analysis is employed to derive this model under the assumption of a two-dimensional doping profile of the LDD region. The results obtained by the model agree well with the two-dimensional PISCES [1] simulations of the electric field in the drain region. Furthermore, the format of the model is readily implementable in a circuit simulator to better understand the mechanisms involved in reducing the electric field in the LDD region with respect to circuit optimisation. Results show the behaviour of the electric field under the influence of the length and doping concentration of the LDD region. Influence of the oxide thickness and junction depth are also accounted for by the model.