Influence of power frequency on the performance of SiC thin films deposited by pulsed DC magnetron sputtering

Because of its high stability, good wear resistance, and high mechanical hardness, SiC is widely used in various mechanical parts as a protective film. However, there have been few reports published on the preparation of SiC films by pulsed DC magnetron sputtering. In this work, SiC films were deposited onto glass and ceramic substrates from a sintered SiC target through pulsed DC magnetron sputtering. The influence of the variation of the power pulse frequency (0 kHz, 50 kHz, 150 kHz, 250 kHz, and 300 kHz) on the film’s performance was studied. The surface morphology, structural characteristics, hardness, and adhesion strength of the deposited SiC films were investigated here. The results show that all the deposited films adhered well to the substrate. They were smooth, compact, and presented an amorphous structure. The film hardness was found to increase as the pulse frequency was increased. When the pulse frequency was 250 kHz, the resulting SiC film possessed optimal mechanical properties with a hardness of 25.74 GPa (measured using a nanometer indentation instrument) and an adhesion strength of about 36 N (measured by scratch tester).