Lower-temperature fabrication of airbridges by grayscale lithography to increase yield of nanowire transmons in circuit QED quantum processors

Publikation: Bidrag til tidsskriftTidsskriftartikelForskningfagfællebedømt

Dokumenter

Quantum hardware based on circuit quantum electrodynamics makes extensive use of airbridges to suppress unwanted modes of wave propagation in coplanar-waveguide transmission lines. Airbridges also provide an interconnect enabling transmission lines to cross. Traditional airbridge fabrication produces a curved profile by reflowing resist at elevated temperature prior to metallization. The elevated temperature can affect the coupling energy and even yield of pre-fabricated Josephson elements of superconducting qubits, tunable couplers, and resonators. We employ grayscale lithography to enable reflow and thereby reduce the peak temperature of our airbridge fabrication process from 200 to 150 °C and link this change to a substantial increase in the physical yield of transmon qubits with Josephson elements realized using Al-contacted InAs nanowires.

OriginalsprogEngelsk
Artikelnummer024004
TidsskriftApplied Physics Letters
Vol/bind123
Udgave nummer2
Antal sider6
ISSN0003-6951
DOI
StatusUdgivet - 10 jul. 2023

Bibliografisk note

Funding Information:
We thank C. Zachariadis for fabrication assistance, J. Kroll and A. Bruno for discussions, and C. Andersen for comments on the manuscript. This research was funded by the European Research Council (ERC) Synergy grant QC-lab, by the Allowance for Top Consortia for Knowledge and Innovation (TKIs) of the Dutch Ministry of Economic Affairs, and by Microsoft Quantum.

Publisher Copyright:
© 2023 Author(s).

ID: 361078436