Microstructures of titanium carbide/diamond-like carbon multilayered films

The titanium carbide/diamond-like-carbon (TiC/DLC) multi-layered films were deposited on Si substrates by unbalanced magnetron sputtering of a 99.99 %(wt.) Ti target with methane as the reactive gas. The impacts of deposition conditions, including deposition time, target current and methane partial pressure, on properties of the multi-layers were studied. Its microstructures and contents were characterized with X-ray diffraction, transmission electron microscopy, Auger electron spectroscopy and Raman spectroscopy. The results show that TiC phase dominates; growth of columnar TiC grains and islands was observed in the transition and TiC layers, respectively. Small amount of diamond phase was observed in the TiC/DLC multi-layer. Moreover, short time for layer deposition, say t<60 s, failed to produce well-defined interface in the multi-layer. The transition layer thickness significantly enhanced the adhesion at the multilayer/substrate interface; the thicker the transition layer, the stronger the adhesion.