Simultaneous characterization of static and induced magnetic fields in high power impulse magnetron sputtering discharges

Hall currents generated in circular planar magnetrons can induce magnetic fields of several mT when operating in high power impulse magnetron sputtering (HiPIMS) mode. Near the target surface, the induced magnetic field is negligible compared to the static one. However, as we move away from the target surface the induced field becomes comparable or even stronger than the static field. In this paper, we investigate the induced magnetic field using Hall sensors, which can directly measure the effective magnetic field (the sum of the static and the induced magnetic fields) and with sufficient time resolution to observe the temporal evolution of the induced field during the HiPIMS pulse. We present the 2D temporal evolution of an induced magnetic field, showing its influence on the effective field. Based on the 2D induced magnetic field map, we calculate numerically the spatial distribution of the Hall currents generating the field, resulting in a current density up to 7 A cm-2. We present these results for both an unbalanced and balanced magnetron configuration.