S. Biesemans et al., NEW CURRENT-DEFINED THRESHOLD VOLTAGE MODEL FROM 2D POTENTIAL DISTRIBUTION CALCULATIONS IN MOSFETS, Solid-state electronics, 39(1), 1996, pp. 43-48
A new method is presented to calculate analytically the threshold volt
age (V-T). A perfect match between theory and experiment can be obtain
ed using a ''current''-definition instead of a ''voltage''-definition
for the V-T. A method to calculate analytically from the Poisson equat
ion the two-dimensional potential distribution profile in CMOS devices
is provided and applied to the Ground Plane nMOSFET. Using this poten
tial, a new expression for the subthreshold current is derived from wh
ich the V-T is calculated. The method is capable of handling long as w
ell as small geometry devices. For the V-T roll-off good agreement wit
h experimental data is achieved for channel lengths down to 0.1 mu m w
ithout using fitting parameters.