Optical spectroscopy study of damage induced in 4H-SiC by swift heavy ion irradiation

S. Sorieul (1) , J.-M. Costantini (2) , L. Gosmain (3) , G. Calas (4) , C. Trautmann (4) , X. Kerbiriou (2)

1 INSTRU
2 SRMA - Service des Recherches Métallurgiques Appliquées
3 SEMI - Service d'Etudes des Matériaux Irradiés
4 IMPMC - Institut de minéralogie et de physique des milieux condensés

Single crystals of 4H-SiC were irradiated with swift heavy ions (332 MeV Ti, 106 MeV Pb and 2.7 GeV U) in the electronic energy loss regime. The resulting damage was investigated with UV-visible optical absorption spectroscopy and micro-Raman spectroscopy. The evolution of the Raman data with fluence shows an accumulation of isolated point defects without amorphization of the material and a partial recrystallization of the structure, but only at the lowest fluence. Furthermore, the longitudinal optical phonon-plasmon coupling mode disappears upon irradiation, suggesting a strong perturbation of the electronic structure. This evolution is consistent with the optical bandgap decrease and the Urbach edge broadening that was also previously observed for the irradiation with 4 MeV Au ions.

Domaines: Minéralogie

S. Sorieul, J.-M. Costantini, L. Gosmain, G. Calas, C. Trautmann, et al.. Optical spectroscopy study of damage induced in 4H-SiC by swift heavy ion irradiation. Journal of Physics: Condensed Matter, 2012, 24, pp.125801. ⟨10.1088/0953-8984/24/12/125801⟩. ⟨hal-00675478⟩