Light ions response of 4H-SiC Schottky diodes with different dopant concentration

Silicon Carbide (SiC) Schottky diodes of different dopant concentration have been used to detect 12C ions at 14.2, 28.1 and 37.6 MeV incident energies. The relation between the applied reverse bias and the thickness of the depleted epitaxial region is studied for different dopant concentrations. The results show that SiC diodes with lower dopant concentration require lower reverse bias values to deplete the same thickness. Moreover, the radiation damage, produced by irradiating SiC diodes with 16O ions at 35.2 MeV, was evaluated by measuring the degradation of both the signal pulse-height and the energy resolution as a function of the 16O fluence. Diodes having a factor 20 lower dopant concentration show a radiation hardness reduced by 60%.