Effect of negative pulsed high-voltage-bias on diamond-like carbon thin film preparation using capacitively coupled radio-frequency plasma chemical vapor deposition

Mechanical properties of diamond-like carbon films by an effective addition of negative pulsed high-voltage-bias have been investigated in capacitively coupled CH4/Ar radio-frequency plasma. The results revealed that hardness and elastic modulus of the deposited film, estimated from nano-indentation load-displacement curve for about 1 μm-thick films, increase with the increase of the absolute value of high-voltage VNPHV for VNPHV < 5 kV and then saturate. Elastic recovery R got the highest value (> 90%) at VNPHV = 5 kV.