Method for detailed evaluation of yield of Nb Josephson junctions

✍ Scribed by Kenji Hinode; Yoshihito Hashimoto; Yoshio Kameda; Tetsuro Satoh; Shinichi Yorozu; Shuichi Nagasawa; Mutsuo Hidaka

• Book ID: 103889714
• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 340 KB
• Volume: 445-448
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2006.05.073

✦ Synopsis

We have developed a method for evaluating I c (critical current) spreading and yield of Nb Josephson junctions (JJ) through detailed current-voltage (I-V) measurements and applied the method to evaluation of 1000 serial arrays. Digitizing the stepwise I-V curve, we deduced the I c value at each voltage step. This allowed us to easily detect irregularities such as junction shortages or I c s that were larger than those of the main distribution by reducing the resolution limit to 1 JJ. Using this method we can take into account very low frequency (<1%) failures in evaluating fabrication processes.