Growth Kinetics of CVD Diamond Films Deposited in Glow Discharge Plasma Using a Pulsed Power Supply

The influence of the parameters of a pulsed power supply of a glow discharge and the substrate temperature on the growth kinetics of CVD polycrystalline diamond films have been studied. It was found that an increase in the pulse frequency from 13 to 50 kHz and a decrease in the pulse duty cycle from 90 to 80% promotes an increase in the films growth rate by 1.5 – 2 times. The non-monotonous character of the dependence of the film growth rate on the deposition temperature upon pulsed excitation of a glow discharge is similar to that characteristic by direct current. In the optimal pulse mode the maximum film growth rate is near a temperature of 1050°C. With an increase in the deposition time, an increase in the average growth rate of the diamond film is observed. When the synthesis process lasts more than 6 hours, the deposition rate reaches 11 μm / hour. The power consumption in the pulsed mode of diamond films synthesis is 0.3 kW / μm, which is 3 times lower than when using a DC power source.