Pulsed DC plasma CVD system for the deposition of DLC films

•A pulsed DC plasma CVD system is developed for DLC films as an alternative of the conventional RF plasma CVD system.•The deposition rate was lower in CO pulsed plasma rather than C2H2.•Soft graphitic and electrically conductive DLC films were obtained from CO while conventional DLC films from C2H2.•Increase of substrate temperature enhanced graphitization in the DLC films deposited from both the source gases.•Highly energy efficient for deposition of DLC films by pulsed DC CVD as compared to a conventional RF plasma CVD system.