Very Large Scale Integration of Nano-patterned YBa2Cu3O7-δ Josephson Junctions in a Two-dimensional Array
Abstract
Very large scale integration of Josephson junctions in a two- dimensional series-parallel array has been achieved by ion irradiating a YBa2Cu3O7-δ film through slits in a nano-fabricated mask created with electron beam lithography and reactive ion etching. The mask consisted of 15,820 high-aspect ratio (20:1), 35-nm wide slits that restricted the irradiation in the film below to form a 28 x 565 Josephson junction array. Characterizing each parallel segment, containing 28 junctions, with a single critical current we found a standard deviation of about 16%. To study array configuration, the number of SQUIDs connected in parallel was decreased by etching the array with photolithography and ion milling. We compare voltage --- magnetic field characteristics for the different configurations and have found that the modulation depth of the voltage has a much stronger than expected dependence on the inductances of the SQUIDs.
- Publication:
-
APS March Meeting Abstracts
- Pub Date:
- March 2010
- Bibcode:
- 2010APS..MARA41014C