Related papers: Low-Loss, High-Coherence Airbridge Interconnects Fabricated by Single-Step Lithography

Low-Loss, High-Coherence Airbridge Interconnects Fabricated by Single-Step Lithography

URL: http://arxiv.org/abs/2601.16416v1
Date: Fri, 23 Jan 2026 03:02:38 GMT
Title: Low-Loss, High-Coherence Airbridge Interconnects Fabricated by Single-Step Lithography
Authors: Jibang Fu, Bo Ren, Jiandong Ouyang, Cong Li, Kechengqi Zhu, Yonggang Che, Xiang Fu, Shichuan Xue, Zhaohua Yang, Mingtang Deng, Junjie Wu,
Abstract summary: Airbridges are essential for creating high-performance, low-parasitic interconnects in integrated circuits and quantum devices.<n>We report a simplified process for fabricating nanoscale airbridges using only a single electron-beam step.
Score: 15.061344064016154
License: http://creativecommons.org/licenses/by/4.0/
Abstract: Airbridges are essential for creating high-performance, low-parasitic interconnects in integrated circuits and quantum devices. Conventional multi-step fabrication methods hinder miniaturization and introduce process-related defects. We report a simplified process for fabricating nanoscale airbridges using only a single electron-beam lithography step. By optimizing a multilayer resist stack with a triple-exposure-dose scheme and a thermal reflow step, we achieve smooth, suspended metallic bridges with sub-200-nm features that exhibit robust mechanical stability. Fabricated within a gradiometric SQUID design for superconducting transmon qubits, these airbridges introduce no measurable additional loss in the relaxation time $T_1$, while enabling a 2.5-fold enhancement of the dephasing time $T_2^*$. This efficient method offers a practical route toward integrating high-performance three-dimensional interconnects in advanced quantum and nano-electronic devices.

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