Mechanistic study of ion-induced diamond nucleation

The effect of low-energy ion bombardment of silicon on diamond nucleation was investigated. By bombarding 100 eV ions of methane and hydrogen on a silicon substrate prior to diamond growth by chemical vapor deposition, diamond nucleation can be immensely enhanced. The ion beam treatment deposited a layer of nano-crystalline graphitic carbon embedded with amorphous SiC. Diamond then nucleated on the graphite overlayer; the nucleation density increased with increasing ion dose. At 1 x 10¹⁹ ions cm^-2, a nuclei density of 4 x 10⁸ cm^-2 was obtained. These results show that ion bombardment of the substrate enhances diamond nucleation.