Exploitation of High Voltage CMOS sensors for tracking applications in physics experiments and beyond

Silicon tracking detectors sit at the core of many particle and nuclear physics experiments to measure the trajectory of charged particles produced in collisions or decay processes. The specifications for these detectors are many and often extremely challenging, as they need to track with the highest possible accuracy the many billions of charged particles that are produced every second in an experiment. The state-of-the-art in silicon tracking detectors for the current generation of physics experiments consists of hybrid sensors in planar processes (combined with a separate readout chip) and monolithic sensors in industry-standard CMOS processes. While both approaches are successfully deployed in current experiments, such as the ATLAS and ALICE experiments at the Large Hadron Collider (LHC) at CERN, they are not able to meet all the requirements of future experiments in a single device. Monolithic silicon sensors in industry-standard High Voltage CMOS (HV-CMOS) processes, a variant of CMOS, are the strongest candidate to meet all the specifications for the next generation of physics experiments. HV-CMOS sensors integrate the sensing cell (i.e. the pixel) and the readout chip in a single device (i.e. a sensor chip) that can be as thin as 50 micrometers. HV-CMOS sensors provide good spatial resolution, fast time resolution, excellent radiation tolerance, all at very competitive cost per area. They were first proposed in 2007 and have matured significantly since then. Upcoming experiments that have selected or propose HV-CMOS for their silicon tracking detector, such as the Mu3e experiment at PSI in Switzerland and the Mighty Tracker upgrade for the LHCb experiment at CERN, will showcase its use for large tracking systems for the future.

In this research, I propose to deploy the highly-performant HV-CMOS sensor chips I have developed already in the first phase of my research programme in two physics experiments that will lead to the discovery of exciting new physics. I will target the proton Electric Dipole Moment (pEDM) search proposed by the JEDI collaboration at the COSY synchrotron in Germany initially, followed by the LHCb VELO detector upgrade at the High Luminosity LHC at CERN. Using my highly-performant HV-CMOS sensor chips, I will assemble technology demonstrators and evaluate them in the Liverpool clean rooms and international facilities to demonstrate they meet the specifications required by these experiments. I will seek the commercialisation of my highly radiation tolerant UKRI-MPW sensor technology for commercial applications beyond physics. To benefit the wider society, I will target applications in particle beam therapy, electron microscopy, nuclear facility monitoring and space. I will also deliver large area highly-performant HV-CMOS sensors that will incorporate all the lessons learned during the first phase of my research programme.