Fabrication of (a-nc) boron carbide thin films via chemical vapor deposition using ortho-carborane

Abstract

Amorphous-nanocrystalline (a-nc) boron carbide thin films were prepared by chemical vapor deposition (CVD) by using ortho-carborane as a single-source precursor for inertial confinement fusion (ICF) application. The effects of deposition temperature (Tdep) and total pressure (Ptot) on chemical composition, microstructure, stoichiometry and morphology of the boron carbide films were investigated. The TEM results show that the structure of the film is mainly composed of amorphous boron carbide with dispersive nano-grains, which will be able to improve the mechanical properties of the film with relatively low roughness. The hardness of the (a-nc) boron carbide film obtained in this study reached 20.6 GPa, and roughness of 3.21 nm. The deposited films sized 0.2–1.9 μm in thickness with B/C atomic ratio ranged from 0.14 to 3.29. The deposition rate decreased with increasing deposition temperature and Ptot, while B/C ratio increased.

Keywords

• boron carbide
• thin film
• chemical vapor deposition
• amorphous-nanocrystalline (a-nc)