This master's thesis presents studies of timing properties of the RD50-MPW2 prototype silicon particle detector, which is designed as a monolithic detector using depleted CMOS technology. A monolithic design is an alternative to the well-established hybrid technology, offering many additional benefits, the main being better tracking performance at a lower overall material budget and reduced cost and time of production. These advantages have led the ATLAS collaboration to consider the use of monolithic detectors in the new tracking system, scheduled to be installed during the next upgrade of the experiment. Further research and development efforts focused on improving the technology for future needs of particle physics experiments are in progress as well.
Measurements presented in this work focus on the characterization of timing resolution of the prototype's active pixels and its dependence on the amount of collected charge. The timing resolution was measured in a new way using different methods of generating charge in front of the readout electronics: with the E-TCT technique using pulsed infrared laser light and electrons from a radioactive $^{90}\mathrm{Sr}$ source. Effects of radiation damage on timing resolution have been studied by measuring a sample irradiated with reactor neutrons to an equivalent fluence of $5\cdot 10^{14}~\mathrm{n_{eq}/cm^2}$. The obtained results show a timing resolution of approximately $300~\mathrm{ps}$, which is within expectations for this prototype. The main contribution to the timing resolution is the jitter of the electronics, with minor contributions coming from effects in the charge collection phase. E-TCT measurements show no increase in the timing resolution after irradiation, whereas in $^{90}\mathrm{Sr}$ measurements, the timing resolution improved in the irradiated sample, which is most likely a consequence of slower collection of charge from the undepleted regions of the pixel via diffusion in the unirradiated sample.
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