The ATLASPix3.1 CMOS Pixel Sensor Testbeam Performance and Serial Powering Characterisation

TL;DR

This paper evaluates the performance of the ATLASPix3.1 HV-CMOS pixel sensor, focusing on its testbeam results and serial powering capabilities, demonstrating its suitability for future high-energy physics experiments.

Contribution

It presents the electrical characterization and testbeam performance of the novel ATLASPix3.1 sensor with integrated serial powering regulators.

Findings

Successful operation in triggerless readout mode with zero suppression

Effective serial powering with shunt-LDO regulators demonstrated

Good performance in electron and hadron beam tests

Abstract

High-voltage CMOS (HV-CMOS) pixel technology is being considered for future Higgs factory experiments. The ATLASPix3.1 chip, with a pitch of 50$\mu m$ x 150$\mu m$, fabricated using TSI 180nm HV-CMOS technology, is a full reticle-size monolithic HV-CMOS sensor with shunt-low dropout (LDO) regulators that allow serial powering for multiple sensors. A beam test was conducted at DESY using 3-6 GeV electron beams, with chips operated in triggerless readout mode with zero suppression, demonstrating multi-chip capability. This was further evaluated with hadron beams, both with and without the built-in power regulators. This study presents the electrical characterisations of the shunt-LDO regulators for serial powering and test beam results of ATLASPix3.1 sensors.