Characteristics of NdBa 2 Cu 3 O 7-δ Josephson Junctions fabricated using a high resolution focused ion beam etching technique

High-Tc Josephson junctions using a narrow gallium ion- beam (FIB) technique has the advantage of flexibility in the location and a simple fabrication.Using the FIB system with a nominal ion beam diameter of l0nm, we have investigated the relations between the FIB-etching conditions and the characteristics of NdBa2Cu3O7-δ (NBCO) Josephson junctions. In the case of narrow FIB irradiation width of 50nm, we optimized RSJ-like I-V characteristic condition.