Interface-trap Charges on Recombination DC Current-Voltage Characteristics in MOS Transistors

Steady-state Shockley-Read-Hall kinetics is employed to study the interface-trap charges at the SiO2/Si interface on the electron-hole recombination direct-current current-voltage (R-DCIV) properties in MOS field-effect transistors. The analysis includes device parameter variations of neutral interface-trap density, dopant impurity concentration, oxide thickness, and forward source/drain junction bias. It shows that the R-DCIV curve is increasingly distorted as the increasing of interface-trap charges. The result suggests that the lineshape distortion observed in the past experiments, previously attributed to spatial variation of surface dopant impurity concentration, can also arise from interface-trap charges along the surface channel region.