Reliability and reproducibility of Josephson junction fabrication - Steps towards an optimized process
dc.contributor.author | Osman, Amr | |
dc.contributor.department | Chalmers tekniska högskola / Institutionen för mikroteknologi och nanovetenskap (MC2) | sv |
dc.contributor.examiner | Bylander, Jonas | |
dc.contributor.supervisor | Fadavi Roudsari, Anita | |
dc.contributor.supervisor | Krantz, Philip | |
dc.date.accessioned | 2020-12-03T12:16:02Z | |
dc.date.available | 2020-12-03T12:16:02Z | |
dc.date.issued | 2019 | sv |
dc.date.submitted | 2020 | |
dc.description.abstract | We investigated the reliability and reproducibility of the fabrication process of Al/AlOx/Al Josephson junctions with varying sizes using the cross-type lithography technique. Room temperature resistance measurements on thousands of junctions showed a standard deviation varying from 0.8% and 5.5% depending on the junction size, and a fabrication yield higher than 97%. Additionally, we investigated two steps towards optimizing the fabrication process. Firstly, the Ar-ion milling duration was reduced, whose e ect on the junction quality remains to be investigated. Secondly, a one-step fabrication technique of Josephson junction is proposed in this thesis. Such a technique reduces the number of lithography steps needed, and in addition, Arion milling of the substrate is avoided. This technique proves to be very reliable for small JJ sizes, with a fabrication yield also higher than 97%. However, further work is needed in order to reduce its standard deviation, in addition to low temperature measurements to investigate the quality of qubits fabricated using these JJs. Finally, a tentative study for the ageing of Josephson junctions was investigated over the course of 180 days showing an average increase in the resistance of only 5%. | sv |
dc.identifier.coursecode | MCCX04 | sv |
dc.identifier.uri | https://hdl.handle.net/20.500.12380/302101 | |
dc.language.iso | eng | sv |
dc.setspec.uppsok | PhysicsChemistryMaths | |
dc.title | Reliability and reproducibility of Josephson junction fabrication - Steps towards an optimized process | sv |
dc.type.degree | Examensarbete för masterexamen | sv |
dc.type.uppsok | H |