Nanolithography of Amorphous Vanadium Oxide Films Using an Atomic Force Microscope

The amorphous vanadium oxide film nanolithography was demonstrated for the first time using scanning probe microscopy. As a result of the local anodic oxidation, vanadium V$^{\mathbf{+4}}$ contained in the initial films passes into its highest oxidation state V$^{\mathbf{+5}}$ under normal conditions. This leads to the formation of local protrusions on the surface of the films ranging in size from 1 to 100 nm. The effect of the thickness and composition of VO$_{\mathbf{x\, }}$ films, atmospheric humidity, and lithography modes on the quality of the nanolithographic pattern is analyzed. The threshold voltage, at which stable film oxidation processes occur, is determined. Lithographic lines with a lateral dimension of less than 100 nm and a thickness of less than 1 nm were achieved. The obtained results are of interest as a new method for precision nanolithography of VO$_{\mathbf{x\, }}$ systems and open the way to the formation of devices with new functionality based on complex vanadium oxides.