THE EFFECTS OF DOPANTS ON THE CHEMISTRY AND TRIBOLOGY OF SPUTTER-DEPOSITED MOS2 FILMS

The fact that dopants improve the friction and weal properties of sput tered MoS2 films is well known. However, the role of dopants in the me chanisms governing friction and wear are not well understood. The purp ose of this work is to gain a fundamental understanding of their role by co-depositing a number of materials, i.e., Ni, Fe, Au, and Sb2O3, w ith MoS2 and evaluating their effects on film chemistry, crystallinity , microstructure, and tribology. Friction and wear measurements were c ollected using ball-on-flat and dual-rub shoe tribometers. Other physi cal and chemical properties were obtained using SEM, XPS, XRD and Rama n spectroscopy. Crystalline MoS2 was seen in all of the films. In Sb2O 3-doped films, an amorphous phase was also observed. The presence of d opants caused film densification and affected crystallite size. They h ad little effect on the overall crystallite orientation. In addition, dopants caused a reduction in the mean and variance of the friction co efficient and an increase in wear life. The correlation between dopant s, film properties, and tribology is discussed in detail.