GIDL (gate-induced drain leakage) and parasitic schottky barrier leakage elimination in aggressively scaled HfO/sub 2/TiN FinFET devices

We demonstrate that for aggressively scaled FinFETs, with 2nm HfO
₂
and TiN metal gate (i.e., workfunction close to midgap), several parasitic leakage mechanisms that impact the off-state current become dominant. We provide a detailed characterization of these mechanisms as well as design guidelines for eliminating them by careful junction dopant placement and S/D silicide engineering in order to achieve high Ion/Ioff ratios. Up to 20times GIDL reduction is achieved with minimum drive loss with asymmetric extensions. Using selective epitaxy on S/D, suppression of parasitic Schottky effects is also demonstrated resulting in a Ioff reduction of 10000times