  This paper depicts the actual variation of gate induced drain leakage current
with impurity doping concentration by complete qualitative and quantitative
approach. De Casteljaus algorithm is applied to describe the band to band
tunneling in a thin gate oxide nMOSFET and the results are remarkably matched.
Moreover for the very first time, the dependency of the leakage current over
impurity density in the MOSFET drain region is explained in the context of pure
geometrical approach. Surprisingly one of the proportionality constant exactly
behaves like impurity gradient which results same characteristics as MOSFET
Drain impurity doping profile measured using 2D simulator.
