Deposition and Investigation of Amorphous Hydrogenated Carbon Films from Acetylene Plasma 1

Abstract – The result of the researches of amor-phous hydrogenated carbon (DLC) films deposi-tion on metal samples are presented. The operating regimes for DLC films deposition on metal samples were obtained. It was found that for the formation of hard adhesive DLC films on a metal surface a high-voltage negative pulse bias (more than 5 kV) is required. It is shown that DLC film deposition on stainless steel results in increase of surface hardness from 4–5 to 9–11 GPa. At that the meas-ured hardness H to modulus of elasticity E ratio, making about 0.1, is typical for diamond-like car-bon films. For hardening the SS surface, nitriding or N ion implantation from the surrounding bulk plasma can be used before deposition of DLC films. The nitriding (with negative dc or bipolar bias voltages) during 5 h leads to an increase in SS sur-face hardness from 4–5 to 16–17 GPa. The implan-tation of the specimens from the bulk nitrogen con-taining plasma during 1 h provides an increase in SS surface hardness from 4–5 to 13–15 GPa. The most significant increase in surface hardness is found for N-implanted HSS specimens with DLC films deposited at amplitudes of negative bias volt-age of –10 and –15 kV. The specimens obtained in this mode display hardness greater than that of the initial specimens, of the DLC film deposited on the initial HSS surface, and of the N-implanted speci-mens without DLC coatings. 1