Fabrication of Ultrasmall High-Quality Bi2Sr2CaCu2O8+delta Intrinsic Josephson Junctions

作者：Matsumoto Tetsuro^*; Kashiwaya Hiromi; Shibata Hajime; Eisaki Hiroshi; Yoshida Yoshiyuki; Kashiwaya Satoshi

来源：Applied Physics Express, 2008, 1(10): 101701.

DOI：10.1143/APEX.1.101701

The fabrication of ultrasmall high-quality intrinsic Josephson junctions (IJJs) using a cuprate superconductor is critical for the realization of a qubit. We investigated the mechanism of damage induced by a Ga+ beam in a Bi2Sr2CaCu2O8+delta IJJ during focused ion beam (FIB) processing. On the basis of the results, we developed a process that allowed the successful fabrication of an ultrasmall and high-quality IJJ. The damage induced by the FIB is reduced by restricting the direction of the Ga+ beam so that the junction area is not directly irradiated by the ion beam. The fabricated ultrasmall IJJ device has a junction area of 0.3 mu m(2) and shows excellent current-voltage characteristics.

• 出版日期2008-10