Van der Waals (vdW) heterostructures are promising for building tunneling field-effect transistors (TFETs), owing to an inherent narrow vdW gap between two stacked materials induced by the dangling bond free surface. However, the band to band tunneling (BTBT) of such a vdW heterostructure TFET strongly depends on the layer-dependent band structure variation at the interface. Here, we report a first principle simulation on the BTBT transition of the monolayer ReS 2 based heterostructures with monolayer and bilayer WSe 2 . An obvious decrease of the turn-on gate voltage from 36 V to 12 V was achieved by adding a layer of WSe 2 due to the band gap narrowing and momentum conservative Γ-Γ tunneling. Under the gate voltage of 20 V with bias of 0.271 V, the upper limit of the BTBT saturate current density in bilayer WSe 2 vdW heterojunction can reach 934 μ A μ m −1 . These results show the bilayer WSe 2 heterojunctio...

中文翻译：

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WSe 2 / ReS 2 van der Waals异质结中与层有关的带间隧穿

范德华（vdW）异质结构有望用于构建隧穿场效应晶体管（TFET），这是由于悬空的无键表面引起的两种堆叠材料之间固有的狭窄vdW间隙。但是，这种vdW异质结构TFET的能带隧穿（BTBT）强烈取决于界面处与层有关的能带结构变化。在这里，我们报告了基于单层ReS 2的单层和双层WSe 2异质结构的BTBT过渡的第一原理模拟。由于带隙变窄和动量保守Γ-Γ隧穿，通过添加WSe 2层，可以将导通栅极电压从36 V明显降低至12V。在栅极电压为20 V，偏置电压为0.271 V的情况下，双层WSe 2 vdW异质结中BTBT饱和电流密度的上限可以达到934μAμm -1。这些结果表明双层WSe 2异质结...