Advances in Ultrafast Laser Micro-/Nanofabrication and Its Applications in Optoelectronic Devices

Abstract

Owing to their ultrashort pulse duration and high peak power, ultrafast lasers enable the fabrication of micro-/nanostructures and the localized tailoring of material properties in a wide range of materials through strong nonlinear absorption, with a limited heat-affected zone. This paper reviews four representative approaches—laser ablation, femtosecond laser direct writing, laser-induced periodic surface structures, and two-photon polymerization—focusing on their applications in photodetection, photovoltaics, light-emitting devices, integrated optics, and emerging optoelectronic materials. Ultrafast lasers can improve optical responses through surface light trapping and refractive‑index modification, and tailor material functionality through defect engineering or doping. Nevertheless, laser processing may also increase dark current, enhance interfacial recombination, induce thin-film cracking, and raise propagation loss. The principal challenges include limited processing throughput, poor process transferability, material damage, and the absence of standardized evaluation protocols. Applicability will require beam shaping and parallel processing, strengthened in situ monitoring and process‑data collection, and integration with conventional micro‑/nanofabrication.