Study of fully-depleted Ge double-gate n-type Tunneling Field-Effect Transistors for improvement in on-state current and sub-threshold swing

作者：Liu, Xiangyu; Hu, Huiyong^*; Wang, Meng; Zhang, Heming; Cui, Shimin; Shu, Bin; Wang, Bin^*

来源：Physica E: Low-Dimensional Systems and Nanostructures , 2018, 95: 51-58.

DOI：10.1016/j.physe.2017.08.014

• Fully-depleted (FD) structure
• Double-gate (DG)
• Tunneling Field-Effect Transistors (TFET)
• Subthreshold swing (SS)

In this paper, a fully-depleted (FD) Ge double-gate (DG) n-type Tunneling Field-Effect Transistors (TFET) structure is studied in detail by two-dimensional numerical simulation. The simulation results indicated that the on-state current Ion and on-off ratio of the FD Ge DG-TFET increases about 1 order of magnitude comparing with the Conventional Ge DG-TFET, and I-on=3.95x10(-5) A/mu m and the below 60 mV/decade subthreshold swing S=26.4 mV/decade are achieved with the length of gate L-D=20 nm, the workfuntion of metal gate Phi(m)=0.2 eV and the doping concentration of n(+)-type-channel N-D=1x10(18) cm(-3). Moreover, the impacts of Phi(m), N-D and L-D are investigated. The simulation results indicated that the off-state current I-off includes the tunneling current at the middle of channel I-B the gated-induced drain leakage (GIDL) current IGIDL. With optimized Fm and ND, Ioff is reduced about 2 orders of magnitude to 2.5x10(-13) A/mu m with LD increasing from 40 nm to 100 nm, and on-off ratio is increased to 1.58x10(7).

• 出版日期2018-1
• 单位西安电子科技大学