Atomic ribbon formation in the pulsed laser patterning of WS2 layers

Abstract

The precise modulation of the thickness of two-dimensional (2D) semiconductor transition metal disulfides (TMDs) by laser thinning techniques to tailor their electronic properties is recognized as a promising approach. However, achieving sub-diffractive patterning during layer-by-layer modulation is crucial for junction fabrication and device engineering. Herein, we report atomic nanoribbon generation in single-layer tungsten disulfide (WS₂), namely, the atomic laser-induced periodic surface structure (atomic-LIPSS) effect, achieved by tuning the laser pulse width, energy and other processing parameters. We explore the structural evolution of WS₂ during laser processing for monolayer and multilayer films and compare it with another more commonly encountered 2D material, MoS₂. It is verified experimentally and by molecular dynamics simulations (MD) that such atomic nanoribbons can only be formed under the action of short-pulse (<ns) lasers.