New analytical expression for the drain current of short-channel MOS transistors in the triode region

Neglecting the effects of the source and drain electric fields on the depletion-layer charge, and consequently on the drain current, cannot be justified in short-channel MOS transistors. The existing geometrical approach for analysing this problem, known as a charge-sharing model, gives good agreement with experimental data only if an extremely complex expression for the drain current is used. In the letter the use of Gauss´s law as a more general approach to analysis of the fringing field effect has been proposed. Using this approach, a simple expression for the drain current of short-channel MOS transistors, which shows excellent agreement with experimental data, has been derived.