Realization of regular arrays of nanoscale resistive switching blocks in thin films of Nb-doped SrTiO3

We report on the realization of short-range-ordered arrays of nanoscale resistive switching blocks in epitaxial Nb-doped SrTiO3 thin films. These blocks can be individually addressed by the tip of a conductive tip atomic force microscope and reversibly switched between a high and a low resistance state reaching an R-off to R-on ratio of up to 50. Scanning micrometer-scale areas with an appropriately biased tip, all blocks within the scanned area can be switched between the two resistive states. We suggest a connection between these nanoscale switching blocks and defect-rich nanoclusters which were detected with high resolution transmission electron microscopy. (C) 2008 American Institute of Physics.