Towards Silicon Carbide Monolithic Active Pixel Radiation Sensors

Future collider experiments require tracking detectors with rapid data acquisition, high spatial and temporal resolution, and exceptional radiation hardness. Monolithic active pixel sensors (MAPS), based on silicon CMOS technology, have demonstrated excellent spatial and temporal resolution. However, for enhanced radiation hardness, wide bandgap semiconductors like silicon carbide (SiC) are promising candidates. This study marks the first step toward integrating MAPS with SiC-CMOS technology. We used the Fraunhofer IISB 2µm SiC-CMOS process to design the first stage of the MAPS electronic read-out chain: a charge-sensitive amplifier (CSA) circuit. Simulations indicate that an equivalent noise charge of 107e is achievable for a sensor capacitance of 1pF. The bandwidth reached 31kHz, which was constrained by the relatively large transistor sizes currently available in SiC-CMOS technology. Although SiC-CMOS is still in its early stages, we believe that with advancements in integration density, SiC-MAPS could become a viable and compelling alternative to silicon-based sensors.