Development of MKIDs in the Optical and Near-Infrared Bands for SPIAKID

• DOI: 10.1007/s10909-023-03018-5
• Publication Date: 2023-12-13T09:02:29Z
• Authors: Hu Jie; Nicaise Paul; Boussaha Faouzi; Martin Jean-Marc; Chaumont Christine; Marret Alexine; Reix Florent; Firminy Josiane; Vacelet Thibaut; Pham Viet Dung; Piat Michel; Caffau Elisabetta; Bonifacio Piercarlo
• Keywords: Large format

9 pages, 6 figures. Accepted by the Journal of Low Temperature Physics<br/>SpectroPhotometric Imaging in Astronomy with Kinetic Inductance Detectors (SPIAKID) aims at designing, building, and deploying on the sky a spectrophotometric imager based on microwave kinetic inductance detectors (MKIDs) in the optical and near-infrared bands. MKIDs show a fast response and the ability to resolve photon energy compared to the conventional Charge-coupled Devices (CCDs). In this paper, we present the design and simulation of the MKID arrays for SPIAKID. The detectors consist of four arrays with each array of 20,000 lumped-element pixels, and each array will be read with 10 readout lines. %The array is designed to have resonances between 4-8GHz with a frequency spacing of 2 MHz and a coupling quality factor (Qc) of about 50000. The meander material of the resonators is trilayer TiN/Ti/TiN to have better uniformity of the critical temperature across the array. We also present the measurement result for a test array with $30\times30$ pixels which is a subset of the designed 2000-pixel array to verify the design and fabrication. The current measured best energy resolving power $R = E/ΔE$ is 2.4 at $λ= 405~$nm and the current medium R is around 1.7. We have also observed the response of the TiN/Ti/TiN is much smaller than expected.<br/>