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 105 photons, at 120 mK and 4-7 GHz. This makes these films promising for microwave kinetic inductance detectors and on-chip millimeter-submilimeter filters.
@article{arxiv.2012.07692,
title = {Characterization of low-loss hydrogenated amorphous silicon films for superconducting resonators},
author = {Bruno T. Buijtendorp and Juan Bueno and David J. Thoen and Vignesh Murugesan and Paolo M. Sberna and Jochem J. A. Baselmans and Sten Vollebregt and Akira Endo},
journal= {arXiv preprint arXiv:2012.07692},
year = {2023}
}
Comments
Presented at the SPIE Astronomical Telescopes + Instrumentation 2020. Full published paper, poster and video available at https://doi.org/10.1117/12.2562233