Optical and structural properties of 6H–SiC irradiated by Si3+⧹He+Si3+⧹He+ coimplantation

Single crystal 6H–SiC irradiated by Si3+⧹He+Si3+⧹He+ coimplantation was studied to analyze changes in structural and optical properties by Raman spectroscopy, UV–visible transmittance spectroscopy and Fourier transform infrared reflectance. Four ion irradiation experiments were performed, He+ (single), Si3+ (single), Si3+ + He+ (successively) and Si3+ & He+ (simultaneously). The fluences for 18 MeV Si3+ and 2.2 MeV He+ at the damage peak are 0.55 dpa and 35 appm, respectively. The synergistic effect due to Si3+ and He+ simultaneously implanted into SiC is higher than that of sequential irradiation. Helium will aggravate irradiation damage when it is introduced into SiC. Defects such as vacancies due to displacement damage stabilized by helium are related to the optical absorption band. Optical defects induced by heavy ions are related to elastic collisions which occur at the nuclear energy loss region. Simultaneous recovery of defects due to dynamic annealing effects resulting from the excessive heat induced by dual-ion irradiation was observed.