Deposition of tungsten nitride thin films by plasma focus device at different axial and angular positions

Tungsten nitride thin films were deposited on stainless steel–304 substrates by using a low energy (2 kJ) Mather type plasma focus device. X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and microhardness are used to study the surface of treated samples. The XRD analysis shows that the degree of crystallinity of deposited thin films strongly depends on axial and angular positions of samples. The SEM micrographs of the deposited films at different angular positions (0°, 10° and 30°) and axial position of 8 cm show that the content of WN sub-micro crystalline structures on the surface of deposited films decreased with increasing the angle with respect to anode axis. From AFM results we observe that for the sample deposited at 8 cm and 0° axial and angular positions, respectively, the most uniform surface and the most homogenous distribution of grains are obtained. Also the hardness results show that the highest mechanical hardness is obtained when the film is deposited at 8 cm and 0° axial and angular positions, respectively.