Free-standing silicon shadow masks for transmon qubit fabrication

Abstract

Nanofabrication techniques for superconducting qubits rely on resist-based masks patterned by electron-beam or optical lithography. We have developed an alternative nanofabrication technique based on free-standing silicon shadow masks fabricated from silicon-on-insulator wafers. These silicon shadow masks not only eliminate organic residues associated with resist-based lithography, but also provide a pathway to better understand and control surface-dielectric losses in superconducting qubits by decoupling mask fabrication from substrate preparation. We have successfully fabricated aluminum 3D transmon superconducting qubits with these shadow masks and found coherence quality factors comparable to those fabricated with standard techniques.

arXiv comment6 pages, 6 figures, additional experimental data - new figure, typos corrected, supplementary material (2 pages, 1 figure, 1 table)

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Cited by in corpus (11)

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• Comparison of Dielectric Loss in Titanium Nitride and Aluminum Superconducting Resonators
• Path toward manufacturable superconducting qubits with relaxation times exceeding 0.1 ms
• Vacuum-gap transmon qubits realized using flip-chip technology
• Coherent superconducting qubits from a subtractive junction fabrication process
• An Integrated Quantum Material Testbed with Multi-Resolution Photoemission Spectroscopy
• Two-Level Systems in Nucleated and Non-Nucleated Epitaxial alpha-Tantalum films
• The superconducting circuit companion -- an introduction with worked examples
• Material matters in superconducting qubits
• Parity-protected superconducting qubit based on topological insulators
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