Impact of High-kappa Spacer on Junctionless Transistor in Sub-Threshold Regime

We investigated the impact of high-kappa spacers on the off-state leakage current due to band-to-band tunneling (BTBT) in junctionless transistors (JLTs). In off-state, a significant band overlap between valence band of channel region and conduction band of drain region triggers the electrons to tunnel from valence band of channel region to conduction band of drain region and increases the off-state leakage current. Here we show that in off-state the vertical fringing electric field through the high-kappa spacer to the device layer increases tunneling distance along tunneling path of electron and reduces tunneling leakage currents.