Quasi-1-Dimensional Dual-Gate MoS2 Field-Effect Transistors with 50 nm Channel Length

Quasi-1-dimensional dual-gate MoS2 field-effecttransistors(FETs) are demonstrated with channels composed of an array of nanospikesource/drain electrodes. This geometry creates an effect of electricfield tailoring and can laterally confine the conducting channel intocharge nanoribbons. Due to effective lateral charge confinement belowthreshold, MoS2 transistors with 50 nm channel length showgreatly improved gate control when compared to conventional FETs withflat edge source/drain electrodes of the same channel length. Thedevice design also results in reduced drain induced barrier loweringand high intrinsic gain of 91 dB. Patterning of the source/drain electrodesinto an array of nanospikes results in a reduction of charge injectionperimeter without significant change in on-current and contact resistance.More importantly, these advantages are achieved without etching thesemiconductor into nanoribbons, which typically results in enhancedscattering. The proposed device geometry is well suited for scalingdown to channel lengths much smaller than 50 nm, especially when usedwith symmetric double gating or single gate FETs with high-k gate dielectrics.