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Circuit-aware Device Modeling of Energy-efficient Monolayer WS$_2$ Trench-FinFETs

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 نشر من قبل Tarun Agarwal
 تاريخ النشر 2021
  مجال البحث فيزياء
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The continuous scaling of semiconductor technology has pushed the footprint of logic devices below 50 nm. Currently, logic standard cells with one single fin are being investigated to increase the integration density, although such options could severely limit the performance of individual devices. In this letter, we present a novel Trench (T-) FinFET device, composed of a monolayer two-dimensional (2D) channel material. The device characteristics of a monolayer WS$_2$-based T-FinFET are studied by combining the first-principles calculations and quantum transport (QT) simulations. These results serve as inputs to a predictive analytical model. The latter allows to benchmark the T-FinFET with strained (s)-Si FinFETs in both quasi-ballistic and diffusive transport regimes. The circuit-level evaluation highlights that WS$_2$ T-FinFETs exhibit a competitive energy-delay performance compared to s-Si FinFET and WS$_2$ double-gate transistors, assuming the same mobility and contact resistivity at small footprints.



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