Characterization, Simulation and Test Beam Data Analysis of Stitched Passive CMOS Strip Sensors

TL;DR

This paper presents the design, simulation, laboratory characterization, and test beam analysis of stitched passive CMOS strip sensors, demonstrating their potential for large-area, radiation-hard detectors in high-energy physics experiments.

Contribution

It introduces a novel stitching technique for passive CMOS sensors that enables large-area, radiation-hard detectors suitable for LHC upgrades.

Findings

Sensors show good performance before and after irradiation.

Stitched sensors achieve the required strip lengths for LHC upgrades.

Test beam results confirm the sensors' suitability for high-energy physics applications.

Abstract

In the passive CMOS Strips Project, strip sensors were designed at the University of Bonn and produced by LFoundry in 150 nm technology, with an additional backside processing from IZM Berlin. Up to five individual reticules were connected by stitching at the foundry in order to obtain the typical strip lengths required for the LHC Phase-II upgrade of ATLAS or CMS trackers. After dicing, sensors were tested in a probe station and characterised with a Sr90-source as well as laser-based edge- and top-TCT systems. Sensors were also simulated using Sentaurus TCAD. At last, detector modules were constructed from several sensors and thoroughly studied in two beam campaigns at DESY. All of these measurements were performed before and after irradiation. This contribution provides an overview of simulation results, summarises the laboratory measurements and in particular presents first test beam results for irradiated and unirradiated passive CMOS strip sensors. We are demonstrating that large area sensors with sufficient radiation hardness can be obtained by stitching during the CMOS process, and presenting our plans for the next submission in the framework of this project.