Diamond Like Carbon Deposition by Inverted Fireballs

A novel approach that employs the plasma phenomenon of inverted fireballs (FBs) was used to deposit chromium containing diamond like carbon (DLC) films on various substrates. The DLC films were obtained with a H2/CH4 feed-gas mixture. Three different types of substrates - graphite, SiC and stainless steel (SS) were coated with 4 – 12 μm thick DLC films. The deposited layers were evaluated by several methods such as Raman spectroscopy (in the visible and UV), EDX, XPS, SEM and Vickers hardness measurements. All characterization data are consistent. The sp3 content of the films was estimated by means of Raman spectroscopy and XPS. Both methods yield a sp3 content of approx. 55% which is corroborated by the Vickers hardness measurements that were found to be as large as 10000.