Mi. Faley et al., JOSEPHSON-JUNCTIONS, INTERCONNECTS, AND CROSSOVERS ON CHEMICALLY ETCHED EDGES OF YBA2CU3O7-X, Applied physics letters, 63(15), 1993, pp. 2138-2140
A technique of ultraviolet photolithography of YBa2Cu3O7-x and PrBa2Cu
3O7-x films combined with nonaqueous Br-ethanol chemical etching was d
eveloped. Josephson junctions, interconnects, and crossovers on the ba
sis of chemically etched edges of c-axis oriented YBa2Cu3O7-x thin fil
ms were prepared and investigated. For the Josephson junctions with a
PrBa2Cu3O7-x barrier, the I(c)R(n) 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 o
bserved in the temperature range up to about 89 K. Critical current sp
reads of about +/-10% were observed. At 77 K, the electrodes of crosso
vers carried more than 10(6) A/cm2. For a 160-nm-thick SrTiO3 intermed
iate layer in crossovers, a resistivity of more than 10(9) OMEGA cm wa
s achieved at T less-than-or-equal-to 100 K.