Formation of nanocrystalline diamond by hydrocarbon plasma beam deposition

Abstract Diamond crystallites up to 40 nm in size have been grown from a highly ionised plasma beam of acetylene for ion energies close to 100 eV per C atom and substrate temperatures above 450°C. This shows that diamond can be grown by physical vapour deposition from an ion-rich plasma as well as by chemical vapour deposition from a radical-rich plasma. The formation mechanism is argued to be one of nucleation and growth rather than a stress-induced transformation from graphite.