INTERFACIAL ANALYSIS OF CVD DIAMOND ON COPPER SUBSTRATES

Diamond growth on Cu substrate by means of a microwave plasma-assisted chemical vapor deposition (CVD) method has been studied. Scanning ele ctron microscopy (SEM) photographs show that the diamond grains deposi ted on Cu substrate mainly appear to have triangular (111) faces in co mparison with those deposited on Si substrate under the same condition s. High resolution electron microscopy (HREM) research indicates that there exists a graphite intermediate laver between CVD diamond and its Cu substrate in which a small amount of amorphous carbon is embedded. The thickness of the intermediate layer varies from a few up to sever al tens of nanometers, depending on the local conditions. The cracks a re found in some thicker intermediate layer regions, which is consider ed to be one of the main factors accounting for the adhesion problem. The registry between {111} planes of some diamond particles and the be neath-graphite (0002) planes has also been evidenced by HREM. The appe arance of the (111) texturing diamond film is supposed to be closely r elated to the graphite intermediate layer. (C) 1997 Elsevier Science S .A.