CCAT: LED Mapping and Characterization of the 280 GHz TiN KID Array

TL;DR

This paper details the design, LED mapping, and characterization of a 280 GHz TiN KID array for the CCAT Prime-Cam instrument, aiming to improve detector yield and performance for submillimeter astronomy.

Contribution

It introduces the first TiN-based 280 GHz KID array for CCAT Prime-Cam and demonstrates LED mapping techniques to optimize detector frequency placement.

Findings

Successful LED mapping of the TiN KID array

Reduced frequency collisions through lithographic trimming

Enhanced array yield and detector performance

Abstract

Prime-Cam, one of the primary instruments for the Fred Young Submillimeter Telescope (FYST) developed by the CCAT Collaboration, will house up to seven instrument modules, with the first operating at 280 GHz. Each module will include three arrays of superconducting microwave kinetic inductance detectors (KIDs). The first KID array fabricated for the 280 GHz module uses titanium-nitride (TiN) as the superconducting material and has 3,456 individual detectors, while the other two arrays use aluminum. This paper presents the design and laboratory characterization of the 280 GHz TiN array, which is cooled below its critical temperature to ~0.1 K and read out over six RF feedlines. LED mapping, a technique for matching the measured resonant frequency of a detector to its physical position, was performed on the array so that the results can be used to lithographically trim the KID capacitors and increase the yield of the array by reducing frequency collisions. We present the methods and results of LED mapping the 280 GHz TiN KID array before deployment on FYST.