Nanopatterning of thin amorphous vanadium oxide films by oxidation scanning probe lithography

Oxidation scanning probe lithography is one of the most promising techniques for nanostructuring. Vanadium oxides constitute a class of functionally rich materials that are promising for various practical applications and have unique physical properties. Currently, the formation of nanocrystals and nanostructures with well-defined dimensions is a challenging task. This study presents a detailed investigation of the processes involved in oxidation scanning probe lithography on the surface of thin amorphous vanadium oxide (VOx) films. It was shown that the oxidizable regions of the film transform into a water-soluble vanadium pentoxide (V2O5) in accordance with classical redox reactions. The oxidation kinetics was shown to be consistent with the Cabrera-Mott model. Dissolving the oxidized regions in water resulted in the formation of nanohole arrays with defined sizes in VOx films. Nanostructures with a depth of less than 0.3 nm and lateral dimensions of less than 50 nm were obtained at relative humidity of about 10 %. It was demonstrated that VOx films about 10 nm thick can be completely oxidized in local areas, enabling the formation of isolated nanostructures. The considered method of nanostructuring VOx is promising for the formation of novel photonic and nanoelectronic devices.