Combined analysis of HPK 3.1 LGADs using a proton beam, beta source, and probe station towards establishing high volume quality control

TL;DR

This study combines multiple measurement techniques to thoroughly characterize HPK type 3.1 LGAD sensors, ensuring their suitability for high-precision timing detectors in future collider experiments.

Contribution

It demonstrates that probe station measurements can reliably predict LGAD performance, aiding high-volume quality control for detector production.

Findings

LGAD response to test beam particles is accurately reproduced with a beta source.

Probe station measurements of gain implant predict sensor response and operation.

Gain implant uniformity is sufficient for full-sized sensors in collider detectors.

Abstract

The upgrades of the CMS and ATLAS experiments for the high luminosity phase of the Large Hadron Collider will employ precision timing detectors based on Low Gain Avalanche Detectors (LGADs). We present a suite of results combining measurements from the Fermilab Test Beam Facility, a beta source telescope, and a probe station, allowing full characterization of the HPK type 3.1 production of LGAD prototypes developed for these detectors. We demonstrate that the LGAD response to high energy test beam particles is accurately reproduced with a beta source. We further establish that probe station measurements of the gain implant accurately predict the particle response and operating parameters of each sensor, and conclude that the uniformity of the gain implant in this production is sufficient to produce full-sized sensors for the ATLAS and CMS timing detectors.