Atomic Force Microscope Based Lithography of YBa2Cu3O7-δ Thin Films

Abstract

We demonstrate the patterning of controlled, arbitrary structures into the surface of thin film YBa2Cu3O7-δ samples by application of a bias voltage between the sample and the tip of an atomic force microscope operated in contact mode, and programmed to trace out the desired structure. The modified volume, as observed above the film surface, is shown to increase linearly with the applied bias voltage, beyond some threshold value, suggesting an electrochemical anodisation process, while increasing the scan speed results in a decrease in the modified volume, but an apparent improvement in homogeneity. Energy dispersive X-ray measurements support the scenario of oxidation as the means of modification, while measurements of current flow into the modified region indicate that it is insulating, offering potential application of the technique to the fabrication of superconducting device elements.