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A detailed experimental study of high power impulse magnetron sputtering discharges is performed using time-resolved ground state density mapping of the sputtered neutrals and ions. This Paper deals with the effects related to the plasma-on phase and can be considered as an extension of Paper I being published simultaneously. The influence of plasma pulse duration, pulse energy, gas pressure as well as molecular oxygen admixture on the spatial and temporal particle density evolution is examined. Special attention is given to the temporal evolution of the ionization fraction distribution of the sputtered atoms. In addition, the 2D vector maps reflecting particle propagation, sputtering, and ionization in the discharge volume are also presented and discussed, similarly to the first part of this study [J. Appl. Phys. 128, 043303 (2020)].

A detailed experimental study of high power impulse magnetron sputtering processes is performed by time-resolved imaging of the ground state sputtered particles. New details related to the behavior of both neutral and singly ionized atoms are shown, as a result of separate treatment of the plasma-on and plasma-off time phases. In Paper I, the ion/neutral density redistribution in the ionization zone during sputtering is analyzed; the role of main discharge parameters, such as pulse repetition rate, pulse energy, etc., is discussed systematically. The time-resolved evolution of the ground state levels population for both sputtered neutrals and ions is also considered. In addition, propagation of the sputtered particles is analyzed using 2D density gradient diagrams calculated based on the measured particle density distributions. The results of this work are compared, when possible, to the data obtained previously [Britun et al., J. Appl. Phys. 117, 163302 (2015)].