A charge sheet model for small geometry MOSFET's

A charge sheet DC MOSFET model for small geometry devices is derived. It takes into account the drain induced barrier lowering and high field effects at the drain side. This model includes the diffusion component; the current expression is therefore valid in a continuous way for all regions of operation including the subthreshold regime. Two important saturation mechanisms are brought out by the analysis : at low current a diffusion mode and at high current a drift mode. I-V characteristics are predicted, within the limits of process parameter variations, using as inputs only physical and structural constants.