Speaker
Description
4H silicon carbide (4H-SiC) is emerging as a promising candidate for radiation sensors in high-energy physics, medicine, and high-temperature environments. It offers intrinsically low leakage currents, even after irradiation, together with fast charge-carrier transport and excellent thermal stability. Historically, studies of 4H-SiC detectors were constrained by the limited access to advanced fabrication processes. Recent industrial and research interest, however, has enabled large-volume production and a broader range of device types, allowing the first systematic evaluation of spatially resolving 4H-SiC detectors and statistically robust irradiation studies.
We present results from the second fabrication run of planar 4H-SiC detectors within the RD50 SiC-LGAD project, comprising two wafers with epitaxial layer thicknesses of 50 µm and 100 µm produced at CNM. The production includes a large number of pn-diodes, strip sensors, and also the first 4H-SiC–based DC resistive devices with 2D spatial resolution. We performed electrical characterization at both wafer and device level, revealing <200fA leakage current levels. The resistive sensors were scanned via UV-laser injection to assess their 2D position resolution. We further discuss passivation-related production issues that rendered some structures, such as Van der Pauw test structures, non-functional.
A substantial fraction of the characterized pn-diodes has been deployed to ongoing proton and neutron irradiation campaigns spanning low to high fluences. These studies aim to inform improvements of simulation models, quantify radiation-induced defects in 4H-SiC, and evaluate the material's suitability for next-generation, radiation-hard detector technologies.