The Carbon vacancy related EI4 defect in 4H SiC

Son, N. T.*; Carlsson, P.*; Isoya, Junichi*; Morishita, Norio; Oshima, Takeshi; Magnusson, B.*; Janzn, E.*

Defects in high-purity semi-insulating 4H SiC irradiated with 2 MeV electrons at room temperature were studied using Electron paramagnetic resonance (EPR). The EPR signal named EI4 defect increased with annealing temperature up to 750 C. Additional large-splitting Si hyperfine (hf) structures and C hf lines by the interaction with one C nucleus were investigated. Based on the observed hf structures, the C symmetry as well as the annealing behaviour, the EI4 defects is determined to be the complex between two carbon vacancies and a carbon antisite in the neutral charge state, VVC. The formation of the complex is interpreted in terms of the migration of the silicon vacancy and the formation of the carbon vacancy-carbon antisite pair next to a carbon vacancy.