Molecular dynamics simulations of the growth of thin amorphous hydrogenated carbon films on diamond surface

TL;DR

This study uses molecular dynamics simulations to explore how hydrogen content and kinetic energy of radicals influence the growth and structure of amorphous hydrogenated carbon films on diamond surfaces.

Contribution

It provides new insights into the atomic-level growth mechanisms of a-C:H films and how hydrogen content is affected by radical energy during deposition.

Findings

Hydrogen content decreases with higher radical kinetic energy.

The local structure of a-C:H depends on hydrogen content.

The ratio of sp3 bonded carbon atoms varies with hydrogen incorporation.

Abstract

The growth of thin amorphous hydrogenated carbon films (a-C:H) on diamond (111) surface from the bombardment of CH2 radicals is studied using molecular dynamics simulations. The structural analysis shows that the local structure (e.g., the first coordination number of C atoms) of a-C:H depends critically on the content of hydrogen. The increase of kinetic energy of incident radicals leads to the decrease of hydrogen content, which subsequently changes the ratio of sp3 bonded C atoms in a-C:H.