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A combination of steered arc process and modified pulsed arc process was investigated in order to determine the effects on the plasma and on the coating qualities during deposition. Titanium, titanium–aluminium and chromium were used as target materials. The work pressure was 1 Pa with nitrogen as work gas. The usage of a pulsed arc current instead of a continuous arc current leads to an accelerated spot movement during the pulse period. The pulse phase also causes the division of the formerly single spot into multiple spots. Those multiple spots move on average on the circular trace that can be observed also without pulsed arc currents. Therefore the spot traces and their velocity leave vary only locally while the pulse current is applied. Another trait of the process combination is the attenuation of the plasma focussing compared with the pure modified pulsed arc process. This weakening influences the film thickness uniformity.

As shown in previous publications concerning cathodic arc deposition, the vacuum arc as a technological tool can be very complexly influenced by variation of the electrical arc parameters. The pulsed arc current and the resulting ion current influence the formation of the coating. To determine optimised parameters for the deposition process, the dependence on the frequency, on the rate of current rise and on the maximum pulse current in particular were investigated. Using the variation of the output parameters of a pulsed arc power supply, the ion current was steered in its shape and its absolute values. Therefore, the shape of arc current pulses was varied, especially in the phase of rise and fall (triangle, sine, rectangle). Among other things, it was noted that at the beginning of the pulse an excessive increase in ion current is measurable. In order to use this increase for a more effective coating process, experiments were carried out using pulses with controlled slopes and current levels or double pulses of rectangular shape. The examinations have shown that an increase in the ion current ratio in the arc current can be reached by a suitable choice of the electrical parameters. The plasma can be controlled by the electrical parameters of the current source.

The interaction of the substrate temperature and the deposition rate in a vacuum arc deposition process were investigated with regards to dependence on static and dynamic arc current parameters. Two different deposition systems both for industry as well as for laboratory application distinguished in shape and volume of the recipient were used for the experiments. In reference to the d.c. process one can achieve the same deposition rate at a noticeably lower substrate temperature when using the modified pulsed arc process. Furthermore, it is obvious without a detailed analysis that the quality of the coatings deposited by the pulsed arc is fairly higher. In order to control the substrate temperature via the pulse parameters the r.m.s. ion current has to be changed (at a constant average current). Using a theoretical model a decreased substrate temperature at higher ion energy was found.