Selective nucleation and growth of diamond particles by plasma-assisted chemical vapor deposition

Diamond particles have been selectively synthesized on a SiO₂ dot-patterned Si substrate using plasma-assisted chemical vapor deposition (plasma CVD). Nucleation densities on both Si and SiO₂ have been increased, first by pretreatment using abrasive powders; then, to eliminate the pretreatment effect from almost all of the substrate and to retain the effect only at designed sites, an Ar beam is used to obliquely irradiate the pretreated substrate. After deposition using plasma CVD, diamond particles have selectively formed on one edge of the SiO₂ dots according to the pattern and have grown large to adjoin with adjacent particles. Polycrystals with equal grain sizes have been synthesized.