Design of a monolithic front-end readout chip with a high-precision TDC and a time-based ADC in CMOS technology for PET imaging

Positron Emission Tomography (PET) is a noninvasive molecular imaging that measures in vivo biodistribution of imaging agents labeled with positron-emitting radionuclides. The physical principle is based on the detection of gamma radiations resulting from the disintegration of positrons emitted by the radiotracer. This thesis focuses on the design of a full-custom front-end readout ASIC dedicated to the Photonics Corp. Multi-channel plate photodetector (MCP) with LYSO crystals. In this study, the crystals are oriented in the axial direction and read out on both sides by individual photodetector channels allowing the spatial resolution and the detection efficiency to be independent of each other. Both the energy quantity and the time information should be measured. Three prototype chips are designed in AMS 0. 35 μm CMOS technology. They include front-end analog signal processing circuits, a high-precision multi-channel time-to-digital converter, and a high-resolution multi-channel time-based ADC. For the future developments, the performance evaluation of a monolithic front-end readout ASIC including front-end analog processing circuits, multi-channel TDC circuits and proposed time-based ADC circuits will be carried out. Moreover, since CMOS technology scaling has moved the process node to nanometers, design considerations for the challenges due to technology scaling will be taken into account.