Developments in Direct Nanopatterning of Graphene; Towards Direct Write.

Abstract:

Graphene, with its exceptional electronic, mechanical, and thermal properties,remains a cornerstone material for next-generation nanoelectronics. However,conventional lithographic approaches to graphene patterning are fraught withchallenges, including contamination, alignment complexity, and scalabilityconstraints. This review critically examines the evolving landscape ofdirect-write graphene technologies, focusing on forefront strategies such asfocused electron beam-induced deposition (FEBID), polymer-to-graphene(P2G) conversion, focused ion beam (FIB) modification, and laser-assistedgraphitisation. These techniques represent a departure from traditionaltop-down or transfer-based methods by enabling bottom-up, spatiallyresolved patterning without intermediary masking steps. Particular attentionis devoted to the physicochemical mechanisms that underlie electron- andphoton-mediated graphitisation, the role of precursor chemistry and substrateinteractions, as well as the influence of beam parameters on sp2 -carboncontent and structural ordering. The review further delineates the limitationsintrinsic to current methodologies, including partial graphitisation, resolutionfidelity, and hardware constraints, and proposes a roadmap to achieve truly“direct” graphene writing. This includes in situ processing under controlledenvironments, advanced beam control systems, and the adoption of catalyticand graphitizable precursors. Collectively, this work provides a comprehensivefoundation for the rational design of next-generation nanofabricationprotocols and underscores the transformative potential of direct-writetechniques in enabling scalable, high-fidelity graphene-baseddevices.

Funding:

The European Union’s Horizon Europe research and innovation programme under the grant agreement No.101087143 (Electron Beam Emergent Additive Manufacturing (EBEAM)). The National Natural Science Foundation of China (Grant No. 52071225). The National Science Centre, project 2021/41/B/ST5/04328.