Device Regions

Device region is determined by both Vds and Vgs. The following figure shows the region of N-type BSIM4 device. Saturation region can be splitted to three regions corresponding to different dominant physical mechanism: channel length modulation (CLM) effect, drain-induced barrier lowering (DIBL) effect, and the substrate current induced body effect (SCBE).

For P-type device, all the voltage in figure is negative. Vtm is the thermal voltage which is about 0.026V for 300K temperature.