Separation of interface and nonuniform oxide traps by the DC current-voltage method

Areally nonuniform distribution of oxide charge gives a significant distortion in the gate capacitance and subthreshold DC drain current versus DC gate voltage characteristics. This distortion prevents a reliable determination of the spatial profile of interface and oxide traps generated when a MOS transistor is subjected to channel hot carrier stress. A new procedure is demonstrated which separates the nonuniform oxide charge distribution from interface traps by combining the analysis of two experimental DC characteristics: the subthreshold drain-current and the DC base recombination current versus the gate voltage.