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arXiv · 2012.07692

Characterization of low-loss hydrogenated amorphous silicon films for superconducting resonators

Bruno T. Buijtendorp·Juan Bueno·David J. Thoen·Vignesh Murugesan·Paolo M. Sberna·Jochem J. A. Baselmans·Sten Vollebregt·Akira Endo
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Abstract

Superconducting resonators used in millimeter-submillimeter astronomy would greatly benefit from deposited dielectrics with a small dielectric loss. We deposited hydrogenated amorphous silicon films using plasma-enhanced chemical vapor deposition, at substrate temperatures of 100\deg C, 250\deg C and 350\deg C. The measured void volume fraction, hydrogen content, microstructure parameter, and bond-angle disorder are negatively correlated with the substrate temperature. All three films have a loss tangent below $10^{-5}$ for a resonator energy of $10^5$ photons, at 120 mK and 4-7 GHz. This makes these films promising for microwave kinetic inductance detectors and on-chip millimeter-submilimeter filters.

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Bruno T. Buijtendorp, Juan Bueno, David J. Thoen, Vignesh Murugesan, Paolo M. Sberna, Jochem J. A. Baselmans, Sten Vollebregt, Akira Endo. 2020-12-14. Characterization of low-loss hydrogenated amorphous silicon films for superconducting resonators. https://doi.org/10.1117/1.jatis.8.2.028006

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