arXiv:1412.0724 · IEEE Transactions on Applied Superconductivity

Ultraviolet, Optical, and Near-IR Microwave Kinetic Inductance Detector Materials Developments

Paul Szypryt, Benjamin A. Mazin, B. Bumble, Henry George LeDuc, L. Baker

Published Dec 4, 2014• 16 citations

Abstract

We have fabricated 2024 pixel microwave kinetic inductance detector (MKID) arrays in the ultraviolet/optical/ near-IR (UVOIR) regime that are currently in use in astronomical instruments. In order to make MKIDs desirable for novel instruments, larger arrays with nearly perfect yield need to be fabricated. As array size increases, however, the percent yield often decreases due to frequency collisions in the readout. The per-pixel performance must also be improved, namely, the energy resolution. We are investigating ways to reduce frequency collisions and to improve the per-pixel performance of our devices through new superconducting material systems and fabrication techniques. There are two main routes that we are currently exploring. First, we are attempting to create more uniform titanium nitride films through the use of atomic layer deposition rather than the more traditional sputtering method. In addition, we are experimenting with completely new material systems for MKIDs, such as platinum silicide.

DOI: 10.1109/tasc.2014.2377598

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