Scaling nanoribbon transistors with monolayer transition metal dichalcogenides

Nanoscale transistors demand aggressive scaling of all channel dimensions-length, width and thickness. Two-dimensional semiconductors (2DS) provide the ultimate thickness limit, yet good device performance has largely remained restricted to micrometre-wide channels. Here we report monolayer 2DS nanoribbon transistors with both n- and p-type operation, fabricated by a top-down multipatterning process that includes 'anchored' contacts to limit nanoribbon delamination. This approach achieves channel lengths and widths down to 25-30 nm, with minimal edge degradation confirmed through nanoscale characterization, including tip-enhanced photoluminescence. Integrated with thin high-κ gate dielectrics, the devices deliver on-state currents up to 560, 420 and 130 µA µm^-1 at a drain-to-source voltage of 1 V for n-type MoS₂, n-type WS₂ and p-type WSe₂, respectively. These results exceed prior single-gated 2DS nanoribbon reports, with WS₂ improving by more than two orders of magnitude, even for normally off (enhancement-mode) operation. Overall, these findings position top-down patterned 2DS nanoribbons as promising building blocks for future nanosheet transistor architectures.