Carbon-titanium nanocomposite thin films were deposited by DC magnetron sputtering on oxidized silicon substrates in argon. The films were prepared at different deposition temperatures between 25 and 800 °C. Transmission electron microscopy was used to determine the structure of the films. All the C-Ti nanocomposites consisted of columnar TiC structure with average column width ∼10 and 20 nm and a thin carbon matrix. The thickness of the carbon matrix between adjacent TiC columns was ∼2-5 nm. Mechanical properties (hardness, reduced modulus) of C-Ti films showed a distinct variation depending on the deposition temperature. Films deposited at 200 °C had the highest hardness ∼18 GPa and the highest reduced modulus ∼205 GPa. Temperature dependence of the film resistance was measured between 80 and 330 K. C-Ti nanocomposites have a non-metallic conduction mechanism characterized by a negative temperature coefficient of resistivity (TCR). The most negative TCR was observed for films showing high hardness and reduced modulus of elasticity.
- Carbon nanocomposite
- Temperature dependence of resistivity
- Transmission electron microscopy
ASJC Scopus subject areas
- Condensed Matter Physics
- Surfaces, Coatings and Films