Double magnetron self-sputtering in HiPIMS discharges

There is an increasing concern that high power impulse magnetron sputtering (HiPIMS) systems are being disadvantaged by relatively low deposition rates compared with traditional dc magnetrons operating at the same average power input. Nevertheless, a minimization of the losses of ionized and neutral species is possible in HiPIMS discharges. In the described magnetron configuration, the majority of metal ions escaping the discharge volume can be either used for deposition or, if they fail to reach the substrate, for discharge maintenance when charge redistribution from one ionization area to the other takes place. The anode-to-cathode configuration allows the neutrals, which are not deposited on the substrate, to be guided to the other instantaneous cathode and be ionized or re-sputtered. For the same average power input, it becomes possible to increase the self-sputtering efficiency, deposition rate and obtain a versatile control over the film microstructure.