DLC coating of a few microns in thickness on three-dimensional substrates

Abstract

Uniform coating of the thick diamond-like carbon (DLC) on three-dimensional substrates was studied using a hybrid process of plasma-based ion implantation and deposition (PBIID). In the PBIID system, an RF pulse for plasma generation and a negative high-voltage pulse for ion implantation were supplied to a substrate through a single electrical feedthrough. Then the high-density plasma was produced along the substrate, leading to the formation of uniform coating film and the ion implantation on three-dimensional substrates. Ion implantation by PBII technique served to the reduction in compressive residual stress of DLC film and the formation of mixing layer between the DLC film and the substrate. As a result, the thick and good-adhesive DLC film with more than a few μm in thickness was almost uniformly prepared on the surface of cylindrical pipe, triangle prism, and trench structure. The deposition rate was approximately 1 μm/h using the toluene as a precursor gas. The hardness of the DLC films was found to be about 12 GPa by nano-indentation method.