Ultra high Q factor superconducting tantalum resonators on 300 mm Si wafers
2026-06-11 19:01
39 浏览
Superconducting resonators are central to superconducting quantum information
technologies and essential for bosonic qubit architectures, where long-lived storage modes
enable hardware-efficient error correction. Achieving ultra‑high quality factors in scalable
planar circuits is challenging because multiple dissipation channels contribute to the total loss.
Here we report planar alpha‑Ta resonators fabricated on 300 mm ultra‑high‑resistivity
(>10 kOhm cm) intrinsic silicon using industrial processes, achieving median internal Q‑factors
exceeding 40 million and maxima above 60 million. Energy-participation-ratio analysis identify
a dominant participation-controlled interface loss mechanism and places conservative upper
bounds on substrate-associated dissipation. For the best-performing substrate, the inferred
substrate loss tangent is below 1.0 × 10-8, establishing industrial MCZ silicon among the
lowest-loss substrate platforms reported for superconducting resonators. At the same time,
the exceptionally low losses show no clear correlation with commonly cited silicon substrates
metrics such as the room temperature resistivity or the impurity concentrations. More
broadly, our studies establish industrial 300 mm processing, careful interface engineering and
300 mm MCZ silicon substrates as a promising platform for resonator-heavy superconducting
quantum architectures with ultra-high-quality factors.
technologies and essential for bosonic qubit architectures, where long-lived storage modes
enable hardware-efficient error correction. Achieving ultra‑high quality factors in scalable
planar circuits is challenging because multiple dissipation channels contribute to the total loss.
Here we report planar alpha‑Ta resonators fabricated on 300 mm ultra‑high‑resistivity
(>10 kOhm cm) intrinsic silicon using industrial processes, achieving median internal Q‑factors
exceeding 40 million and maxima above 60 million. Energy-participation-ratio analysis identify
a dominant participation-controlled interface loss mechanism and places conservative upper
bounds on substrate-associated dissipation. For the best-performing substrate, the inferred
substrate loss tangent is below 1.0 × 10-8, establishing industrial MCZ silicon among the
lowest-loss substrate platforms reported for superconducting resonators. At the same time,
the exceptionally low losses show no clear correlation with commonly cited silicon substrates
metrics such as the room temperature resistivity or the impurity concentrations. More
broadly, our studies establish industrial 300 mm processing, careful interface engineering and
300 mm MCZ silicon substrates as a promising platform for resonator-heavy superconducting
quantum architectures with ultra-high-quality factors.
Link to the article is here.
