J. Rezek

Ion flux characteristics and efficiency of the deposition processes in high power impulse magnetron sputtering of zirconium

High power impulse magnetron sputtering of zirconium was investigated at the average target power density of up to 2.22 kW cm−2 in a pulse. The depositions were performed using a strongly unbalanced magnetron with a planar zirconium target of 100 mm diameter at the argon pressure of 1 Pa. The repetition frequency was 500 Hz at duty cycles ranging from 4% to 10%. Time-averaged mass spectroscopy was carried out at the substrate positions of 100 and 200 mm from the target. The increase in the average target power density from 0.97 kW cm−2 to 2.22 kW cm−2 in shortened voltage pulses (from 200 to 80 μs) at an average target power density of 100 W cm−2 in a period led to high fractions (21%–32%) of doubly charged zirconium ions in total ion fluxes onto the substrate located 100 mm from the target. However, the respective fractions of singly charged zirconium ions decreased from 23% to 3%. It was observed that ion energy distributions were extended to high energies (up to 100 eV relative to the ground potential)...