Structural and morphological peculiarities of needle-like diamond crystallites obtained by chemical vapor deposition

Polycrystalline (100) textured diamond films containing mixture of micrometer scale crystallites and surrounding them smaller size diamonds and disordered carbon were obtained by chemical vapor deposition from methane‑hydrogen gas mixture activated by a direct current discharge (DC CVD). The films were oxidized during exposure in air at temperature providing selective volatilization of the smallest fraction of diamond crystallites and disordered carbon material. Structural peculiarities of the material remaining after film oxidation were analyzed by electron microscopy and compared with results of computer simulations. The simulations were performed using two dimensional empirical model designed to describe formation of {111} and {100} facets of the diamond crystallites during CVD. The porous and disordered structures at {111} growing facets predicted by the simulation are in excellent agreement with the experimental observations. [Display omitted] •Structural peculiarities of the diamond films obtained by DC PECVD were revealed experimentally using electron microscopy.•Empirical model based on geometrical approach was proposed to describe formation the crystallites composing the CVD films.•Computer simulations were performed using proposed model for {111} and {100} facets of the diamond crystallites.•The experimental and computer simulation results demonstrated perfect agreement confirming proposed model.