Analysis of the exponentially decaying transient current in MOS capacitors

A long time constant transient current of a metal-oxide-semiconductor (MOS) capacitor during gate biasing has been widely studied to analyze the traps in the oxide layer. The time constant is of the order of a few seconds. In this study, we measured the short time constant (typically shorter that 1 s) transient current to analyze the traps located closer to the interface. We consequently found another type of transient current, which is caused by hole trapping at the Si/SiO₂ interface traps. The energy level of the interface traps is 0.2 eV from the bottom of Si conduction band.