A novel carbonization process for 3C-SiC heteroepitaxial growth on Si (100) with mass-separated ion beams (e.g., C-. C-2(-), C+, and CH3+ ions) was carried out by in situ monitoring with reflection high-energy electron diffraction measurements. The kinetic energies of ions and substrate temperatures were in the range of E = 10-700 eV and T = 400-700 degreesC, respectively. This ion-beam induced carbonization process was investigated as a function of various irradiation parameters; i.e., ion kinetic energy, substrate temperatures, charge and mass of ions, ion species, ion irradiation modes. etc. and was compared to conventional carbonization processes with thermal species; e.g., hydrocarbon gases. As a result. the use of energetic ion species allows successful carbonization and provides lower process temperatures by 150-600 degreesC, compared to the conventional processes reported previously. The mechanisms of carbonization reaction with energetic ions are compared to using thermal species.