The Al, Si and Ti targets were sputtered in a reactive atmosphere of argon & oxygen and argon&nitrogen. The pulsed magnetron power supply generated a series of one polarity 160 kHz pulses grouped with 2.5 kHz. The amplitude of negative current pulses was constant and equal to 8 A. Target power was accomplished by varying the number of pulses within an interval. The relations between target surface contamination with reactive compounds and power supply parameters were investigated.