Excimer UV–Induced Selective Etching of Single-Layer Graphene for Tailored Graphene Architectures

The commercial adoption of graphene for next-generation electronics requires fabrication techniques that are clean, precise, and scalable. Conventional O₂ plasma etching with polymer masks causes severe contamination and damage. We introduce a polymer-free method for the selective etching of single-layer graphene (SLG) using a 172 nm Xe₂ excimer UV lamp under ambient conditions. This process utilizes high-energy 172 nm photons to directly dissociate atmospheric oxygen and water, enabling rapid, atomic-layer selective etching without vacuum or controlled gas. Raman analysis confirms a clean three-stage chemical transformation (cleaning, oxidation, etching) and shows minimal edge damage compared to plasma methods. The versatility of this technique is demonstrated through the preservation of intrinsic Graphene Nanoribbons and the fabrication of patterned multilayer heterostructures. This low-damage, highly efficient manufacturing pathway directly addresses critical bottlenecks, paving the way for the commercialization of high-quality graphene devices.