Overlap junctions for high coherence superconducting qubits
Abstract
Fabrication of sub-micron Josephson junctions is demonstrated using standard processing techniques for high-coherence, superconducting qubits. These junctions are made in two separate lithography steps with normal-angle evaporation. Most significantly, this work demonstrates that it is possible to achieve high coherence with junctions formed on aluminum surfaces cleaned in situ by Ar plasma before junction oxidation. This method eliminates the angle-dependent shadow masks typically used for small junctions. Therefore, this is conducive to the implementation of typical methods for improving margins and yield using conventional CMOS processing. The current method uses electron-beam lithography and an additive process to define the top and bottom electrodes. Extension of this work to optical lithography and subtractive processes is discussed.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 17, 2017
- Source ID
- 10.1063/1.4993937
Entities
People
- D. P. Pappas
- H. S. Ku
- J. L. Long
- Mustafa Bal
- Russell E Lake
- Xinghua Wu
Organizations
- Intelligence Advanced Research Projects Activity
- National Institute of Standards and Technology
- University of Colorado