Comparative analysis of working gas composition impact on diamond films microstructure

The paper report a diamond films with dendrite-like or nanofeathers structure. Such structures was synthesized both in CH4/H-2 (12.2-19.3 vol.% CH4) and CH4/H-2/N-2 (7-18.5 vol.% N-2) working gas mixture. The resulting diamond dendrites are composed of diamond crystallites of various sizes, as well as non-diamond carbon, with a height comparable to the film thickness and a lateral size does not exceed 200 nm (the minimum size of detected diamond crystallites is similar to 5 nm). Such diamond structure seems cannot be classified to either conventionally nano- or ultrananocrystalline films. It is shown that nitrogen-rich diamond films have a larger size of both individual diamond crystallites and dendrites, as well as a higher level of residual stresses and roughness, compared to nitrogen-free diamond films. At the same time, nitrogen-free films have higher values of hardness and Young's modulus.

Automated summary

The paper presents diamond films with dendrite-like or nanofeathers structure, synthesized in different gas mixtures. These diamond dendrites consist of diamond crystallites of various sizes and non-diamond carbon, with a height comparable to the film thickness and a lateral size not exceeding 200 nm. The nitrogen content in the gas mixture affects the size, residual stresses, roughness, hardness, and Young's modulus of the resulting diamond films.