PREPARATION AND PROPERTIES OF MOSX FILMS GROWN BY DC MAGNETRON SPUTTERING

Dense and thick MoSx coatings were prepared by d.c. reactive magnetron sputtering of a molybdenum target in an argon and H2S atmosphere onto stainless steel substrates polished to different roughnesses. The deposition rate was 0.3-0.5 μm min-1 and the thickness ranged from 0.7 to 28 μm. Composition, morphology, hardness, crystallographic structure and tribological properties of MoSx coatings were investigated with respect to the deposition parameters (pressure, temperature, substrate bias, gas flow). The hexagonal structure was observed for MoSx layers with x ranging from 1.3 to 2.1. A pin-on-disc apparatus was used to determine the friction coefficient in dry air or nitrogen under a hertzian pressure of about 1 GPa at a speed of 10 mm s-1. These tests revealed a minimum friction coefficient of 0.025 for hexagonal structure and (001)-textured films between MoS1.5 and MoS1.7 with hardness values of 6000 MPa and 4000 MPa respectively (Knoop device) and a thickness of 1 - 4 μm. © 1990.