Tunneling properties of in-situ-fabricated intrinsic Josephson junctions in Bi2Sr2CaCu2O8+x single crystals

Slacks of intrinsic Josephson junctions were fabricated on the surface of Bi2Sr2CaCu2O8+x single crystals, using photolithography and Ar-ion etching. The number of junctions in a stack was controlled by the etching time, while the c-axis I-V and R versus T curves were measured in-situ in a vacuum chamber for T down to similar to 13 K. The tunneling resistance and the I-V curves are scaled by the surface junction resistance. The superconductivity of the surface conducting plane in contact with a Au electrode is weakened by the proximity to the normal metal. In a low-bias region, main tunneling properties of a junction are not affected by the presence of other junctions in a stack. (C) 2000 Elsevier Science B.V. All rights reserved.