Effect of mid-frequency discharge assistance on dual-high power impulse magnetron sputtering

► Hybrid system combining dual-HiPIMS and MF discharges was developed. ► Combination of HiPIMS and MF discharges allows significant reduction of pressure. ► MF discharges causes pre-ionization effect which supports HiPIMS re-ignition. ► High ion energy (~ 15 eV) and efficient ionization of sputtered atoms were observed. ► Energy of incoming particles influences growth of multilayer-structured Ti-Cu film.