%0 Generic %A Buijtendorp, Bruno %D 2024 %T Data underlying the publication: Characterization of low-loss hydrogenated amorphous silicon films for superconducting resonators %U %R 10.4121/ff8e2171-87d6-4bf4-a5cb-7930cf45b366.v1 %K silicon %K amorphous %K a-Si:H %K hydrogenated %K FTIR %K Raman %K ellipsometry %K microwave %K dielectric %K loss %X

Superconducting circuit elements used in millimeter-submillimeter (mm-submm) astronomy would greatly benefit from deposited dielectrics with small dielectric loss and noise. This will enable the use of multilayer circuit elements and thereby increase the efficiency of mm-submm filters and allow for a miniaturization of microwave kinetic inductance detectors (MKIDs). Amorphous dielectrics introduce excess loss and noise compared with their crystalline counterparts, due to two-level system defects of unknown microscopic origin. We deposited hydrogenated amorphous silicon films using plasma-enhanced chemical vapor deposition, at substrate temperatures of 100°C, 250°C, and 350°C. The measured void volume fraction, hydro- gen 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 to 7 GHz. This makes these films promising for MKIDs and on-chip mm-submm filters.

%I 4TU.ResearchData