Enhancement of diamond thin film quality by a cyclic deposition method under MPECVD

Diamond thin films were deposited by a cyclic deposition method, which can be carried out periodically on and off the methane gas flow in the CH4-H2 system, using a microwave plasma enhanced chemical vapour deposition system. The property of diamond thin films deposited using the cyclic process was investigated and compared with that of the normal process. The quality of the diamond films deposited by the cyclic process is better than that by the normal process under the same conditions, although the growth rate of diamond film was lower in the cyclic process. However, introducing the interlayer on silicon substrate prior to the cyclic process leads to the increase in the growth rate which is comparable with that in the normal process while maintaining the same high quality of the films.