Dynamic transition in the discharge current between gas-dominant discharge and self-sputtering in high-power impulse magnetron sputtering

An unstable stage is observed from the discharge current during the transition from gas-dominant discharge to the self-sputtering dominant regime in high-power impulse magnetron sputtering (HiPIMS). The phenomenon and the formation mechanism are time dependent and there is a dynamic transition between the two stable stages. The threshold of the high stable discharge is investigated at different pressure and hybrid DC discharge. According to the derivation of the discharge current, the temperature in the discharge is found to play a major role in the dynamic transition at moderate voltage.