Cold-source paradigm for steep-slope transistors based on van der Waals heterojunctions

Phonon-assisted transport in van der Waals heterostructure tunnel devices

“…However, the ON-current of TFETs based on single 2D materials remains small [1]. In this context, van der Waals heterostructures represent a promising platform to look for future electron devices due to high drive currents and steep swings achievable with vertical tunneling architectures [2][3][4]. One of the main scattering mechanisms present in this type of materials and devices is electron-phonon scattering that must be carefully taken into account for a realistic estimation of device performance.…”

Intrinsic subthermionic capabilities and high performance of easy-to-fabricate monolayer metal dihalide MOSFETs

“…This effect can be engineered by both selecting suitable 2D materials and by tuning the electronic properties of a given monolayer by means of mechanical or chemical methods. A distinctive advantage of cold-source * demetrio.logoteta@for.unipi.it devices with respect to negative-capacitance FETs are their immunity to hysteresis issues, while, compared to tunnel-FETs, they can reach higher levels of ON current and exhibits higher immunity to nonidealities such as traps and band tails [8].…”

“…The cold-source transistors proposed to date leverage a lateral confinement [9] or either vertical [8,10,11] or lateral [12,13] heterojunctions to obtain the required energy-filtering effect. However, the fabrication of this kind of structures, even at a proof-of-concept level, still presents significant challenges.…”

“…LaBr 2 , VI 2 , VBr 2 , VOCl 2 , VOBr 2 ), gathering within an energy window of roughly 0.5 eV. Despite a significant electron-polar optical phonon (POP) interaction is expected in these materials [15], which can favor the electron thermalization and impair the coldsource filtering [8], the electron-POP coupling can be sufficiently screened by engineering the dielectric environment through the use of high-k oxides [16]. We demonstrate the concept by numerically studying the operation of a n-type MOSFET based on a mono- layer of CrI 2 , which, among other possible candidates, exhibits a particularly simple band structure.…”

Dissipative Transport and Phonon Scattering Suppression via Valley Engineering in Single-Layer Antimonene and Arsenene Field-Effect Transistors

“…In light of these considerations, it appears compulsory to take into account the electron-phonon interactions in the simulation of 2D material-based electron devices, in order to obtain reliable quantitative predictions of the device performance at room temperature. Nevertheless, only a few recent simulation studies have fully included the effect of EPC 28,29 . In other works, the mobility has been evaluated through the Takagi formula 30 , which takes into account only the Bardeen-Shockley acoustic-deformation-potential (ADP) scattering 31 and neglects all the optical and intervalley phonon scatterings 13,32 .…”