EPR and ab initio calculation study on the EI4 center in 4H and 6H-SiC
2010 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 82, no 23, 235203- p.Article in journal (Refereed) Published
We present new results from electron paramagnetic resonance (EPR) studies of the EI4 EPR center in 4H- and 6H-SiC. The EPR signal of the EI4 center was found to be drastically enhanced in electron-irradiated high-purity semi-insulating materials after annealing at 700-750°C. Strong EPR signals of the EI4 center with minimal interferences from other radiation-induced defects in irradiated high-purity semiinsulating materials allowed our more detailed study of the hyperfine (hf) structures. An additional large-splitting 29Si hf structure and 13C hf lines of the EI4 defect were observed. Comparing the data on the defect formation, the hf interactions and the annealing behavior obtained from EPR experiments and from ab initio supercell calculations of different carbon-vacancy related complexes, we suggest a complex between a carbon vacancy-carbon antisite and a carbon vacancy at the third neighbor site of the antisite in the neutral charge state, (VC-CSiVC)0, as a new defect model for the EI4 center.
Place, publisher, year, edition, pages
American Physical Society , 2010. Vol. 82, no 23, 235203- p.
IdentifiersURN: urn:nbn:se:liu:diva-56584DOI: 10.1103/PhysRevB.82.235203ISI: 000286767600003OAI: oai:DiVA.org:liu-56584DiVA: diva2:320501
Original Publication: Patrick Carlsson, Tien Son Nguyen, A. Gali, J. Isoya, N. Morishita, T. Ohshima, B. Magnusson and Erik Janzen, EPR and ab initio calculation study on the EI4 center in 4H and 6H-SiC, 2010, Physical Review B Condensed Matter, (82), 23, 235203. http://dx.doi.org/10.1103/PhysRevB.82.235203 Copyright: American Physical Society http://www.aps.org/2010-05-252010-05-252012-08-13