Carbon ion implantation in 4H-SiC eliminates carbon vacancies, enhancing optoelectronic properties without introducing impurities, but excess ions may introduce new defects. Optimizing implantation requires understanding excess carbon's form. In this study, we carried out C^+ implantation experiments on 4H-SiC with MEVVA source at 40 keV, with doses of 1× 10^15, 5× 10^15, 1× 10^16, and 5× 10^16 ions per cm2. Molecular dynamics simulations analyzed defect evolution, showing Ci2 exhibits greater structural stability than Cᵢ1 and Cᵢ3. Ion beam induced luminescence with protons is used to study the defect structures of carbon clusters after implantation. An asymmetric shift in the Donor-Acceptor Pair luminescence peak was ob- served. Gaussian deconvolution analysis revealed that this shift was caused by two new luminescence centers at 2. 54 eV and 2. 65 eV, respectively. Both of these new centers are induced by Ci2 defects. A single-exponential decay model was employed to study the luminescence evolution of the two centers, demonstrating that the 2. 54 eV center exhibits greater stability than the 2. 65 eV center. Moreover, DI defect luminescence was only observed at the lowest C^+ dose of 1× 10^15 ions per cm^2, corresponding to irradiation damage being below the amorphization threshold.
Jiang et al. (Thu,) studied this question.