Towards silicon carbide monolithic active pixel radiation sensors

Abstract

Future collider experiments demand a new generation of tracking detectors with excellent spatial and temporal resolution, along with enhanced radiation hardness. Monolithic active pixel sensors (MAPS) based on silicon CMOS technology are proven to provide fine spatial and temporal resolution while being cost-effective. In terms of radiation hardness, however, wide band-gap semiconductors such as silicon carbide (SiC) promise superior performance. In this work, we make a first step towards MAPS development based on SiC-CMOS technology. We used the Fraunhofer IISB 2 µm SiC-CMOS process to design the first stage in the electronic read-out chain of a MAPS, a charge-sensitive amplifier (CSA). Circuit simulations show that an equivalent noise charge of $95e$ to $205e$ is attainable for an input capacitance in the range of $0.5pF$ to $4.5pF$ at room temperature. The attained bandwidth of $31kHz$ was primarily limited by the large size of the MOSFETs in the used SiC-CMOS technology. We believe that a further increase in integration density could make SiC-MAPS a compelling alternative to its silicon-based counterparts.