Eco-friendly platforms for Next-Generation Electronics: Sustainable Gold Nanowire Fabrication using Pulse-Atomic Force nanolithography on Chitosan Films

The rapid growth of miniaturized, high-performance electronics has created an urgent need for sustainable materials and, consequently, nanofabrication methods that minimize environmental and health impacts. Conventional micro and nanolithography methods rely on toxic materials and energy-intensive processes, contributing to escalating e-waste and environmental inequities. To address these challenges, research has increasingly focused on biodegradable polymers and green lithographic techniques as viable alternatives for next-generation device manufacturing. Here, a fully sustainable nanofabrication strategy that integrates chitosan-based biodegradable thin films with Constant Pulse-Assisted Force Lithography (CP-AFL) for high-resolution nanopatterning is presented. Using CP-AFL, reproducible arrays of nanogrooves with tunable depths, which served as templates for the formation of gold nanowires, were fabricated. This process achieved precise nanoscale control under ambient conditions without the use of toxic chemicals, high-energy radiation, or advanced instrumentation. These results demonstrate the potential of combining biopolymer resists with low-energy, solvent-free lithography to advance eco-friendly micro- and nanomanufacturing. By providing a scalable, industrially compatible, and environmentally benign pathway for device fabrication, this work moves the field closer to sustainable electronics suitable for applications in flexible, biomedical, and transient devices.