Temperature dependence of the resistance switching effect studied on the metal/YBa2Cu3O6+x planar junctions

Resistive switching (RS) effect observed in capacitor-like metal/insulator/metal junctions belongs to the most promising candidates for next generation of memory cell technology. It is based upon a sudden change of the junction resistance caused by an electric field applied to the metal electrodes. The aim of this work was to study this effect on the structure metal/YBCO6/YBCO7, where YBCO7 is a metallic phase and YBCO6 is an insulator phase which arises spontaneously by out-diffusion of oxygen from a few nanometers wide YBCO surface layer. Oriented YBa2Cu3O7 thin films were prepared by the method of magnetron sputtering and consequently planar structures with metal-YBCO junction were made by the means of the optical lithography, ion etching and vacuum evaporation. On these junctions we have studied the temperature dependence of the RS effect with I-V and dI/dV-V transport measurements down to liquid He temperature. We have determined temperature dependence of the RS effect threshold voltage in the temperature range 100-300 K and showed that this dependency is compatible with common idea of oxygen ions migration under electric field within the YBCO surface layer.