SYNTHETIC CVD DIAMOND CVD

摘要

A method for synthesizing diamond materials by chemical vapour deposition (CVD) comprises: providing a substrate, providing a source gas and allowing homoepitaxial diamond synthesis on the substrate. The environment in which synthesis takes place comprises nitrogen at an atomic concentration of between 0.4-50 ppm and the source gas comprises; an atomic fraction of hydrogen, Hf, of 0.4-0.75, an atomic fraction of carbon, Cf, of 0.15-0.3 and an atomic fraction of oxygen, Of, of 0.13-0.4, wherein Hf+ Cf+ Of=1 and the ration of the atomic fractions of carbon and oxygen is 0.45:1 < Cf:Of < 1.25:1 and the hydrogen atoms present in the source gas are added as H2at an atomic fraction of the total number of hydrogen, oxygen and carbon atoms present of 0.05-0.4, wherein Hf, Cf, and Ofare fractions of the total number of hydrogen, oxygen and carbon atoms present in the gas source. Diamond material made by this method and its use as a gemstone or as part of an electronic device is also disclosed.