Two-Dimensional Numerical Substrate Current Modeling For N-channel MOS Transistors

This paper describes a 2D numerical simulation technique for impact ionization. Impact ionization is modeled by a ballistic form of Chynoweth´s formula [27] with an electron transport model including energy transport. Substrate currents resulting from impact ionization measured on devices in a 0.75 /spl mu/m CMOS technology, are compared with simulated results employing this model. The model shows good agreement with these measurements over a wide range of channel lengths and bias conditions.