A series of hot (600 degreesC) and room temperature (RT) C-AI ion co-implanted 6H-SiC epilayers were studied by micro-Raman scattering and photoluminescence. The damage and amorphization of SiC layer by co-implantation, and the elimination/suppresion of the implantation induced amorphous layer via high temperature annealing are observed. The recovery of the crystallinity and the activation of the implant accepters are confirmed. The results from hot or RT co-implantation are compared.