Microstructure and hardness of SiC–TiC nanocomposite thin films prepared by radiofrequency magnetron sputtering

Silicon carbide–titanium carbide (SiC–TiC) nanocomposite thin films were prepared by radiofrequency magnetron sputtering using SiC–TiC composite targets fabricated by spark plasma sintering. The SiC thin films were amorphous at substrate temperatures below 573 K and crystallized in the cubic crystal system (3C) at substrate temperatures greater than 773 K. Cubic SiC–TiC nanocomposite thin films, which contain a mixture of 3C-SiC and B1-TiC phases, were obtained at a TiC content of greater than 20 mol%. The amorphous films possessed a dense cross-section and a smooth surface. The morphology of the SiC–TiC nanocomposite thin films changed from granular to columnar with increasing substrate temperature. The SiC–TiC nanocomposite thin films prepared at TiC content of 70–80 mol% and substrate temperature of 573 K showed the highest hardness of 35 GPa.

► SiC–TiC nanocomposite film was prepared by sputtering with SiC–TiC composite target.
► SiC–TiC composite film consisted of fine SiC and TiC grains in a nanometer size.
► SiC–TiC (70–80 mol% TiC) films showed higher hardness than those of composite body.