Production, Quality Assurance and Quality Control of the SiPM Tiles for the DarkSide-20k Time Projection Chamber

TL;DR

This paper describes the production process, quality assurance protocols, and validation results for SiPM Tiles used in the DarkSide-20k liquid argon TPC dark matter detector, ensuring high performance and uniformity.

Contribution

It introduces a comprehensive QA-QC protocol for SiPM Tiles, demonstrating high production yield and suitability for cryogenic operation in a large-scale dark matter experiment.

Findings

Production yield exceeds 83.5%.

Tiles meet performance requirements for cryogenic operation.

Validation confirms robustness and uniformity.

Abstract

The DarkSide-20k dark matter direct detection experiment will employ a 21 m^2 silicon photomultiplier (SiPM) array, instrumenting a dual-phase 50 tonnes liquid argon Time Projection Chamber (TPC). SiPMs are arranged into modular photosensors called Tiles, each integrating 24 SiPMs onto a printed circuit board (PCB) that provides signal amplification, power distribution, and a single-ended output for simplified readout. 16 Tiles are further grouped into Photo-Detector Units (PDUs). This paper details the production of the Tiles and the quality assurance and quality control (QA-QC) protocol established to ensure their performance and uniformity. The production and QA-QC of the Tiles are carried out at Nuova Officina Assergi (NOA), an ISO-6 clean room facility at LNGS. This process includes wafer-level cryogenic characterisation, precision flip-chip bonding, wire bonding, and extensive electrical and optical validation of each Tile. The overall production yield exceeds 83.5%, matching the requirements of the DarkSide-20k production plan. These results validate the robustness of the Tile design and its suitability for operation in a cryogenic environment.