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arXiv · 1710.11255

Fabrication of antenna-coupled KID array for Cosmic Microwave Background detection

Q. Y. Tang·P. S. Barry·R. Basu Thakur·A. Kofman·J. Vieira·E. Shirokoff
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Abstract

Kinetic Inductance Detectors (KIDs) have become an attractive alternative to traditional bolometers in the sub-mm and mm observing community due to their innate frequency multiplexing capabilities and simple lithographic processes. These advantages make KIDs a viable option for the $O(500,000)$ detectors needed for the upcoming Cosmic Microwave Background - Stage 4 (CMB-S4) experiment. We have fabricated antenna-coupled MKID array in the 150GHz band optimized for CMB detection. Our design uses a twin slot antenna coupled to inverted microstrip made from a superconducting Nb/Al bilayer and SiN$_x$, which is then coupled to an Al KID grown on high resistivity Si. We present the fabrication process and measurements of SiN$_x$ microstrip resonators.

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Q. Y. Tang, P. S. Barry, R. Basu Thakur, A. Kofman, J. Vieira, E. Shirokoff. 2017-10-30. Fabrication of antenna-coupled KID array for Cosmic Microwave Background detection. https://doi.org/10.1007/s10909-018-1941-0

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