ANALYTICAL THEORY OF 2-DIMENSIONAL CHARGE SHEET MODEL FOR SHORT-CHANNEL MOSFETS UNDER NON-LINEAR CHARGE CONTROL

An analytical theory of two-dimensional charge sheet model of short ch annel IGFETs under non-linear charge control which geometrically takes into account the two-dimensional edge effect is developed. This theor y includes the effects of non-uniform doping and uses the charge sheet model approach. Since the diffusion current plays an important role i n subthreshold and saturation regions, the model also takes it into ac count along with the drift current. The model thus proposed is more ac curate than the earlier models as it includes the effects of diffusion and leads to an exact analytical expression for the device current. T he results obtained are compared with those of uniform doping. II is f ound that the current magnitude starts out greater for non-uniform dop ing and as the gate voltage is increased, the increase in current slow s down and approaches to that of uniform doping.