Isotopically-purified Si-28 homoepitaxial and cubic-type 3C-(SiC)-Si-28-C-12 films were grown by means of an ion-beam deposition (IBD) method with single Si-28(-) ion beams and dual Si-28(-) and C-12(+) ion beams, respectively. For the Si film, the surface structural evolution during IBD film growth was investigated. The Si isotopic composition of the resulting Si epitaxial film was Si-28:(29)si:Si-30 = 99.9982 at% :0.0016 at% :0.0002 at%. For the SiC film, the effect of the kinetic energy of the ions on the initial growth temperature of the 3C-SiC crystalline phase was investigated. While an annealing temperature of 720 degreesC was required for the crystallization of the amorphous SiC film grown at room temperature, the crystallization temperature of the SiC film growth during ion beam irradiation onto heated substrates was 600 degreesC. The TO phonon frequency of the 3C-(SiC)-Si-28-C-12 obtained by this method showed a blue shift that was similar to8 cm(-1) higher than that of "natural" 3C-SiC with natural isotopic composition.