Solvent-free microfabrication of thin film device using the focused ion beam

We introduce a novel fabrication technique for thin film devices, utilizing Focused Ion Beam micro-machining. Unlike conventional methods requiring post processes such as etching or solvent treatment, this method involves creating a pre-patterning step-like structure on the substrate before growing the thin film, achieving the desired device pattern right after thin film deposition. As an example, we fabricated devices with VO ₂ thin film of which electrical transport properties are examined. The VO ₂ devices exhibit robust metal-insulator transition behavior and V-I characteristics, indicating the high quality of the patterned devices. The results indicate that our approach enables intricate patterning, comparable to conventional e-beam lithography, without the risk of sample degradation. The simplicity, stability, and versatility of this technique suggest new possibilities for thin film device fabrication.