An Analytical Model for Hybrid Multiple-Gate (HMG) Tunnel FET

Based on the quasi-3D/quasi-2D scaling theory, quasi-3D/quasi-2D potential approach, WKB approximation and Kane’s model, a new analytical model including the channel potential, on/off drain current, and threshold voltage is developed for the hybrid multiple-gate (HMG) tunnel FET (TFET) with a small scaling length $(\lambda sRG)$ of surrounding-gate (SRG) TEFT near the source side and a large scaling length $(\lambda_{DG)}$ of double-gate (DG) TEFT near the drain side. It is found that with the HMG structure, the tunnel path caused by $\lambda sRG$ in the source-channel region can be effectively decreased, which hence enhances the on-state current. Besides, the off-state current can be efficiently suppressed by the HMG structure due to long tunnel path induced by $\lambda_{DG}$ in the drain-channel region.