Local Epitaxial Growth of Diamond on Nickel from the Vapour Phase [and Comment]

Deposition of diamond on nickel substrates has been performed by a microwave plasma reactor from methane-hydrogen gas mixtures. Growth features and the structures of the deposits have been studied as functions of methane concentration (0.3-5.0% (by volume)) and substrate temperature (700-1000 degrees C). At methane concentrations lower than 0.9%, diamond crystals, which have epitaxial relation to the substrate, have been observed to grow both on (111) and (100) faces of nickel. Other phenomena not observed with usual substrates have also been noted, and are believed to be caused by the unique properties of nickel.