Comparison of bulk and epitaxial 4H-SiC detectors for radiation hard particle tracking

Measurements and simulations have been carried out using bulk and epitaxial SiC detectors. Samples were irradiated to fluences of around 10/sup 14/ hardrons/cm/sup 2/. Material of thickness 40/spl mu/m gave a charge collection efficiency of 100% dropping to around 60% at 100 /spl mu/m thickness. Detailed MEDICI simulations incorporated the main defect levels in SiC, the vanadium center, Z-center and a mid-gap level as measured by deep level transient spectroscopy and other techniques. Calculated recombination currents and charge collection efficiencies at varying fluences were comparable to experimental data. The study suggests that SiC detectors will operate up to fluences around 10/sup 16//cm/sup 2/ as required by future particle physics experiments.