Surface Modifications of CMR Manganite Thin Films Using Atomic Force Microscope

Reproducible nanoscale surface lithography have been produced on La00.66Ba0.33MnO3 thin films using Atomic Force Microscopy. Using an anodic oxidation technique, structures were produced using both positive tip bias voltages as well as negative tip voltages. The electric field produced by applying a positive tip bias acts to reduce the region near the surface, whereas negative tip bias causes an oxidation reaction. Using a positive tip bias, stable structures were consistently achieved which demonstrated a linear dependence of height and width on tip voltage and writing speed. Heights ranged from 5 – 50 nm and widths from 400 – 2000 nm. Negative bias voltages produced a rapid oxidation of the surface, resulting in uncontrollable writing. After etching with a 50% HCL solution it was found that controlled writing was possible with negative bias voltages.