Dissipative transport and phonon scattering suppression via valley engineering in single-layer antimonene and arsenene field-effect transistors

Abstract

Two-dimensional (2D) semiconductors are promising channel materials for next-generation field-effect transistors (FETs) thanks to their unique mechanical properties and enhanced electrostatic control. However, the performance of these devices can be strongly limited by the scattering processes between carriers and phonons, usually occurring at high rates in 2D materials. Here, we use quantum transport simulations calibrated on first-principle computations to report on dissipative transport in antimonene and arsenene n-type FETs at the scaling limit. We show that the widely-used approximations of either ballistic transport or simple acoustic deformation potential scattering result in large overestimation of the ON current, due to neglecting the dominant intervalley and optical phonon scattering processes. We additionally investigate a recently proposed valley engineering strategy to improve the device performance by removing the valley degeneracy and suppressing most of the intervalley scattering channels via an uniaxial strain along the zigzag direction. The method is applicable to other similar 2D semiconductors characterized by multivalley transport.

Ohmic Behavior in Metal Contacts to n/p-Type Transition-Metal Dichalcogenides: Schottky versus Tunneling Barrier Trade-off

“…In particular, thanks to their extreme flexibility and large piezoresistance, group VI TMDs like MoS 2 have great potential in many applications spanning from fast thermal sensors to tactile sensing in soft robotics and electronic skin . Moreover, TMDs have attracted remarkable attention for beyond silicon complementary metal oxide semiconductor (CMOS) circuits. , Indeed, despite the successful miniaturization of field-effect transistors (FETs) carried out for several decades, the scaling of silicon-based FETs to channel lengths in the sub-10-nm range appears almost prohibitive, mainly because of severe short channel effects and source-to-drain tunneling. , The monolayer MoS 2 has been identified as a promising baseline material for the ultimately scaled n-type FETs because the combination of subnanometer thickness and low dielectric constant improves the electrostatic integrity of the transistors. Moreover, a band gap larger than 1.7 eV and relatively large effective masses mitigate the source-to-drain tunneling. , …”

“…3 Moreover, TMDs have attracted remarkable attention for beyond silicon complementary metal oxide semiconductor (CMOS) circuits. 4,5 Indeed, despite the successful miniaturization of field-effect transistors (FETs) carried out for several decades, the scaling of siliconbased FETs to channel lengths in the sub-10-nm range appears almost prohibitive, mainly because of severe short channel effects and source-to-drain tunneling. 6,7 The monolayer MoS 2 has been identified as a promising baseline material for the ultimately scaled n-type FETs because the combination of subnanometer thickness and low dielectric constant improves the electrostatic integrity of the transistors.…”

Review on 2D Arsenene and Antimonene: Emerging Materials for Energy, Electronic and Biological Applications

“…Selecting the armchair direction for the transport in the gate lengths shorter than 5 nm results in a 2 times ON‐current improvement. [ 89 ] Using DFT, Shokri et al. have investigated the structural, optical, and electronic properties of antimonene/palladium ditelluride vdW heterostructure.…”

“…Selecting the armchair direction for the transport in the gate lengths shorter than 5 nm results in a 2 times ON-current improvement. [89] Using DFT, Shokri et al have investigated the structural, optical, and electronic properties of antimonene/palladium ditelluride vdW heterostructure. The results show that the most stable configuration of Sb/PdTe 2 heterostructure has indirect bandgap of 0.49 eV with a type-I band alignment.…”

Insights into electronic properties of strained two-dimensional semiconductors by out-of-plane bending

“…Compared with the industrial bulk materials, 2D semiconductors face their new challenges towards further applications. For example, the experimental mobilities lag far behind the theoretical values due to the strong electron-optical phonon coupling, disabling the acoustic-phonon-limited carrier mobility prediction [4][5][6]. Rawat et al systematically calculated the room temperature carrier mobilities of 2D monolayers via different reliable models.…”