THE INTERFACE MORPHOLOGY OF DIAMOND FILM GROWN ON SI

The interfaces between diamond films and silicon substrate have been investigated to obtain a better understanding of the characteristics of diamond-substrate interface. In order to investigate the interface morphology, the backside surface of diamond film and the substrate surface have been observed after the deposited diamond film is separated from the silicon substrate. The vacant space between particles is found on the backside surface of the separated film and the central part of each particle caves in. Also, many of the hillocks are present on the Si substrate surface after the film is removed. From the observations, it is found that the interfaces between the diamond film and the silicon substrate is very rough. It is suggested that such interface morphology is attributed to the etching of the silicon substrate which takes place at the early stage of the synthesis. For the energy dispersive spectroscopy experiment of the backside surface of the separated film, more silicon is detected at the central part of each particle. This result implies that strong Si - C bonds are localized at the center of each particle, which would result in the poor adhesion.