Josephson junctions, interconnects, and crossovers on chemically etched edges of YBa2Cu3O7−x

A technique of ultraviolet photolithography of YBa2Cu3O7−x and PrBa2Cu3O7−x films combined with nonaqueous Br-ethanol chemical etching was developed. Josephson junctions, interconnects, and crossovers on the basis of chemically etched edges of c-axis oriented YBa2Cu3O7−x thin films were prepared and investigated. For the Josephson junctions with a PrBa2Cu3O7−x barrier, the IcRn product values of about 10 mV at 4.2 K and up to about 0.6 mV at 77 K were achieved. Shapiro steps were observed in the temperature range up to about 89 K. Critical current spreads of about ±10% were observed. At 77 K, the electrodes of crossovers carried more than 106 A/cm2. For a 160-nm-thick SrTiO3 intermediate layer in crossovers, a resistivity of more than 109 Ω cm was achieved at T≤100 K.