Template patterning of YBa2CU3O7

We demonstrate the use of thin chromium layers to define structures in YBa2Cu3O7 deposited by laser ablation. The chromium reacts with copper to form an insulating crystalline compound containing copper and chromium in equal amounts. Although the reaction will proceed up to approximately 1 mu m into the defined pattern, the formation of a crystalline compound means that the extent of the reaction is limited by the availability of chromium. We have defined large-area, regular grids of tiny chromium pads, yielding a grid of insulating islands of approximately 600 nm in size after YBa2Cu3O7 deposition. Electrical measurements show the influence of such a pattern on the R-T characteristics of the YBa2Cu3O7.