Deep-Level Defects in Electron Irradiated 6H-SiC

An effect of electron irradiation on the concentrations of deep-level centers in C-rich and Si-rich 6H-SiC wafers is investigated. In the former material, the main deep-level centers with activation energies of E-c-0.50, E-c-0.64 and E-c-0.67 eV are found to be related to dicarbon interstitials and CiNC complexes located in hexagonal and quasi-cubic lattice sites, respectively. In the latter material, the dicarbon interstitials are dominant after the irradiation with 1.5-MeV electrons. At the energy of bombarding electrons equal to 0.3 and 0.7 MeV, the activation energies of the dominant deep-level centers are E-c-0.38 and E-c-0.52 eV, respectively. The first center is related to carbon vacancies and the second to silicon interstitials.