Breaking the width-scaling limit in high-performance atomically thin 2D nanoribbon transistors

Abstract

State-of-the-art transistors have been successfully scaled the gate lengths and channel thicknesses down to 5 nm for high-performance and energy-efficient information processing. However, reducing channel width below 40-50 nm remains a bottleneck, as dangling bonds, edge disorder, and lateral depletion suppress drive current and degrade device performance. Here, we break this width-scaling wall using ultra-scaled two-dimensional semiconductor (2DSC) nanoribbon transistors down to 15 nm. In contrast to the conventional scaling rule of degradation of current density upon width scaling, our atomically-thin monolayer and bilayer molybdenum disulfide nanoribbon transistors exhibit enhancement of on-current density of up to 230% and 170%,respectively, followed by a saturation for the narrowest channels down to 15 nm. The ultra-narrow nanoribbon transistors maintain the highest on/off ratios reported so far for similar device dimensions, with improved mobility and threshold-voltage stability, indicating reduced edge scattering and depletion with a stronger electrostatic control. These findings lead to a breakthrough in width scaling rules using 2DSC nanoribbons with enhanced performance at narrower channel widths, which is promising for the ultimate scaling of transistors.