Characterization of passive CMOS sensors with RD53A pixel modules

TL;DR

This paper explores the use of CMOS foundries for fabricating silicon radiation detectors, demonstrating the feasibility and performance of RD53A pixel modules with a 25x100 μm² cell size for high-energy physics applications.

Contribution

It presents the first characterization of CMOS-based RD53A pixel modules, highlighting their potential for cost-effective, high-performance silicon detectors in particle physics.

Findings

Successful fabrication of RD53A-compatible pixel sensors at LFoundry

Performance demonstrated in charge collection, resolution, and efficiency tests

Potential for scalable, cost-effective detector production using CMOS foundries

Abstract

Both the current upgrades to accelerator-based HEP detectors (e.g. ATLAS, CMS) and also future projects (e.g. CEPC, FCC) feature large-area silicon-based tracking detectors. We are investigating the feasibility of using CMOS foundries to fabricate silicon radiation detectors, both for pixels and for large-area strip sensors. A successful proof of concept would open the market potential of CMOS foundries to the HEP community, which would be most beneficial in terms of availability, throughput and cost. In addition, the availability of multi-layer routing of signals will provide the freedom to optimize the sensor geometry and the performance, with biasing structures implemented in poly-silicon layers and MIM-capacitors allowing for AC coupling. A prototyping production of strip test structures and RD53A compatible pixel sensors was recently completed at LFoundry in a 150nm CMOS process. This presentation will focus on the characterization of pixel modules, studying the performance in terms of charge collection, position resolution and hit efficiency with measurements performed in the laboratory and with beam tests. We will report on the investigation of RD53A modules with 25x100 mu^2 cell geometry.