Published in:
Journal of Vacuum Science & Technology A: Vacuum, Surfaces, and Films, 36 (2018) 2
Language:
English
DOI:
10.1116/1.5001141
ISSN:
0734-2101;
1520-8559
Origination:
Footnote:
Description:
This work reports on the influence of the power density and bias potential on the structure-property relations of sputter deposited amorphous carbon coatings. Coatings were deposited at power densities between 4.4 and 28 W/cm2 in both Ar and Ne atmospheres at pressures of 1 and 1.25 Pa, respectively. Measurements of the substrate temperature during deposition indicate that the coating is subjected to a substantial thermal load during deposition, which leads to growth of the graphitic clusters at higher power densities. This change of the microstructure results in a drop of the hardness of up to 40% when the power density increased to 28 W/cm2. A high hardness of up to 30 GPa, however, can be achieved when either a bias potential of −100 V is applied or when Ne instead of Ar is used as process gas. This can be attributed to the high compressive stresses present as a result of an enhanced ion bombardment.