Developing an empirical relationship for optimizing surface roughness of TiC thin film grown by magnetron sputtering using Taguchi analysis

The surface roughness of thin films coating is an important factor that affects the performance capability of material in industrial and scientific application. Surface roughness influences properties such has nanohardness, wear, friction and corrosion. This research focuses on the influence of RF magnetron process parameters on the surface roughness of TiC thin film grown on Ti6Al4V substrate. Taguchi optimization method was used to determine the contribution ratio of the RF sputtering process parameters and mathematical predictive models were developed for optimization of TiC thin film surface roughness. The structural characterization of the TiC thin film was examined using Grazing incidence X-ray diffractometer. The optimization analysis revealed that the RF power contributed the most to the behaviour of the TiC thin film surface roughness with a contribution rate of 87.97%. The percentage error from the predictive models developed are very meagre and shows good agreement with the acceptable limit. From the GIXRD analysis, the (200) orientation plane was noticed to be the preferential peak in all the coatings.