High-uniformity TiN/Ti/TiN multilayers for the development of Microwave Kinetic Inductance Detector

TL;DR

This paper presents the development and characterization of high-uniformity TiN/Ti/TiN multilayers aimed at improving the pixel yield of Microwave Kinetic Inductance Detectors (MKIDs) used in cryogenic photon detection.

Contribution

The study introduces a new multilayer fabrication process for TiN/Ti/TiN films with enhanced uniformity and compares the results with a statistical model to assess impact on MKID array yield.

Findings

TiN/Ti/TiN multilayers show improved uniformity.

Uniformity correlates with increased pixel yield.

Model predicts yield improvements based on film uniformity.

Abstract

Microwave Kinetic Inductance Detectors (MKIDs) are a class of superconducting cryogenic detectors that simultaneously exhibit energy resolution, time resolution and spatial resolution. The pixel yield of MKID arrays is usually a critical figure of merit in the characterisation of an MKIDs array. Currently, for MKIDs intended for the detection of optical and near-infrared photons, only the best arrays exhibit a pixel yield as high as 75-80%. The uniformity of the superconducting film used for the fabrication of MKIDs arrays is often regarded as the main limiting factor to the pixel yield of an array. In this paper we will present data on the uniformity of the TiN/Ti/TiN multilayers deposited at the Tyndall National Institute and compare these results with a statistical model that evaluates how inhomogeneities affect the pixel yield of an array.