All-2D vertical metal-semiconductor field-effect transistor with sub-10 nm channel and contact lengths
摘要
Two-dimensional (2D) materials are promising candidates for next-generation nanoelectronics in the post-Moore era. However, simultaneously scaling the channel length (Lch) and contact length (Lc) in transition metal dichalcogenide-based field-effect transistors remains a challenge. Here, we introduce an all-2D vertical metal–semiconductor field-effect transistor featuring an MoS2 channel that contacts the sidewall of a graphene (source)–hBN (insulator)–graphene (drain)–hBN (insulator) heterostructure. A self-aligned TiS2–MoS2 Schottky junction ensures full-gate control over the channel. The Lch and Lc are determined by the thicknesses of the bottom hBN and the graphene electrodes, respectively. Consequently, the Lch and Lc can be simultaneously scaled to sub-10 nm with a vertical pitch size of sub-30 nm. The typical device exhibits an on/off ratio > 107 at an operating voltage of ~0.5 V, a subthreshold swing of ~62 mV/Dec, a drain-induced barrier lowering of ~33 mV/V, and an on-state current density of ~144 μA/μm at 1 V. Sentaurus technology computer-aided design simulations further verify the good electrostatic control provided by the full-gate configuration and the bottleneck-free transport within the channel. These results highlight the potential of 2D materials for high-density and low-power integrated circuits.