Intermittent growth of a diamond film by direct current hot cathode plasma chemical vapor deposition

A diamond film was intermittently prepared by direct-current (DC) hot-cathode plasma chemical vapor deposition (PCVD). The intermittent growth was carried out by alternating deposition under methane flow for 20 min and etching for 10 min without methane flow. For comparison, a diamond film was continuously prepared under the same growth conditions without etching. Scanning electron microscopy, Raman spectroscopy and XRD were used to characterize surface morphology, texture and purity of the two diamond films. Results indicated that the diamond film produced by the intermittent growth had smaller amounts of non-diamond phase and its grains were more uniform than that produced by the continuous growth without etching. Amorphous carbon and graphite formed during deposition on the surface of the diamond film can be reduced by etching.