ADHESION AND STRUCTURAL-CHANGES OF MULTILAYERED AND MULTI-DOPED A-C-HFILMS DURING ANNEALING

High residual stress in hydrogenated amorphous carbon (a-C:H) films ma kes them rather difficult to integrate to substrates whose reactivity for carbide formation is low at the deposition temperature. Additional ly, when exposed to thermal cycling, a-C:H films not only soften (i.e. , graphitization), but also peel off because of thermal stresses. To i mprove adhesion and reduce the graphitization at high temperatures, we studied multi-element doped a-C:H films with multi-layered buffer str uctures on austenitic stainless steel substrates. A multi-layered stru cture was deposited in the order of TiC/ TiCN/TiN/Ti/stainless steel p rior to depositing multi-element doped a-C:H films using de reactive s puttering and plasma-enhanced CVD methods. The a-C:H films were doped with Ti and Si. Chemical analyses of the multi-layer structure was per formed using X-ray photoelectron spectroscopy. Adhesion of the films w ith the multi-layered buffers was better than those without buffer lay ers at high temperatures (T=600 degrees C). The critical scratching lo ad was maximum at around 400 degrees C on (Si:Ti)-a-C:H films. Similar ly, as observed by Raman spectroscopy Si:Ti doped films had higher res istance to the graphitization than undoped films.