High rate reactive magnetron sputtered tungsten carbide films

Tungsten carbide films have been deposited on stainless steel substrates held between 300 to 500 °C in a planar rf magnetron sputtering system at rates as high as that of pure tungsten (825 A°/min). The effect of substrate temperature on formation of WCx films has been investigated. A mixture of hexagonal WC, A-15 W3C and carbon in graphitic and diamond form have been observed by AES and XRD techniques. The microhardness of these films has been found to be as high as 2365 kgf/mm2. The adhesion of these films as measured from indentation crack patterns has been found to depend on substrate temperature as well as on the amount of dispersed carbon in the film.