Preparation of TiC films by alternate deposition of Ti and C layers using a dual magnetron sputtering source

Abstract

Abstract Titanium carbide (TiC) films have been prepared by alternately depositing thin Ti and C layers on aluminosilicate glass substrate by magnetron sputtering. The apparatus used in the experiment was a dual-cathode-sputtering machine with a carousel type substrate holder. By rotating the substrate holder at a rotation speed of 30 rev/min, a thin Ti layer of 0–0.15 nm and a thin C layer of 0–0.072 nm depending on the cathode current were alternately deposited on the substrate. The Ti/C compositional ratios of films were controlled by varying the flux ratio (layer thickness ratio) of the Ti and C sources. This allowed films of Ti, TiC, and C to be prepared. The composition, structure, and hardness of the deposited films were estimated as a function of the source C/Ti flux ratio. The results of X-ray photoelectron spectroscopy showed that the film composition varied continuously from Ti:C=1:0 to 0:1, and that some oxygen was incorporated as an impurity for low C/Ti ratios. The X-ray diffraction measurement results showed that the film structure changed from α-Ti (obtained for a C/Ti flux ratio 0.5), and that the lattice spacing increased continuously with increasing C flux ratio for the polycrystalline TiC films. A maximum microhardness of about 17 GPa was obtained for films deposited at flux ratio of unity. In the sliding wear resistance test, higher abrasive wear resistance was observed for films deposited with C/Ti flux ratios of more than 0.33. The transition of the film structure and composition corresponds well to the film hardness and abrasive wear behavior.