A review of diamond CVD utilizing halogenated precursors

Halogenated carbon-hydrogen diamond chemical vapor deposition (CVD) systems have been observed to enhance low temperature growth, nucleation density and quality when compared to the more common carbon-hydrogen system. The most likely explanation for the enhanced low temperature growth and nucleation densities observed in the halogenated system are a product of high surface hydrogen abstraction rates, enabled by the addition of halogenated species. The increase in diamond quality in the halogenated systems can be accounted for by the preferential etching of graphite by Cl, F and HF. The possible participation of halogen containing radical species in the growth process has also been used to explain the observed results in halogenated diamond CVD systems. However, the short lifespan of these species makes their direct participation in the growth process unlikely in most systems. Insufficient data is available at this time to draw conclusions about halogenated diamond CVD systems not involving F or Cl. (C) 1999 Elsevier Science S.A. All rights reserved.