2025/04/22 by Pilsl, B., Bergauer, T., Casanova, R. +15
#FOS: Physical sciences #High Energy Physics - Experiment (hep-ex) #Instrumentation and Detectors (physics.ins-det)
paper · doi:10.48550/arxiv.2504.15730
The latest HV-CMOS pixel sensor developed by the former CERN-RD50-CMOS group, known as the \mpw, demonstrates competitive radiation tolerance, spatial granularity, and timing resolution -- key requirements for future high-energy physics experiments such as the HL-LHC and FCC. Fabricated using a \SI150nm CMOS process by LFoundry, it introduces several improvements over its predecessor, the RD50-MPW3, including separated power domains for reduced noise, a new backside biasing scheme, and an enhanced guard ring structure, enabling operation at bias voltages up to \SI800V. Tests with non-irradiated samples achieved hit detection efficiencies exceeding \SI99.9% and a spatial resolution around \SI16μm. Neutron-irradiated sensors were characterized using IV measurements and test-beam campaigns, confirming the sensor's robustness in high-radiation environments. The results highlight the ability of HV-CMOS technology to restore hit detection efficiency post-irradiation by increasing the applied bias voltage. Details of these measurements and timing performance are presented in this paper.