Flaking of carbon film was studied by depositing hydrogen doped carbon films on tungsten and molybdenum substrates. Topographies of the carbon coatings were analyzed with scanning electron microscopy and three-dimension profilometer. Secondary ion mass spectrometry and Raman spectra analysis was used to determine the hydrogen concentration and the number of sp3 bonds in the films, respectively. Carbon film properties varied from tetrahedral amorphous carbon (ta-C) to hard hydrogenated amorphous carbon (a-C:H). Carbon coatings hold large residual stresses, which are released during or after deposition. Typical stress relief patterns were observed. In most samples buckling started at some dislocation or at the edge of the film and adhesion energy was deduced from the sizes of the stress relief patterns. It was observed, that carbon films were more adherent to tungsten than to molybdenum and that codeposited hydrogen had a significant effect to flaking propagation in the carbon films.
|Number of pages||5|
|Journal||Physica Scripta T|
|Publication status||Published - 1 Dec 2004|
|MoE publication type||Not Eligible|
|Event||International Topical Conference on Hydrogen in Condensed Matter - Helsinki, Finland|
Duration: 25 Jun 2003 → 28 Jun 2003