Hysteresis behaviour of reactive high power impulse magnetron sputtering

摘要

Hysteresis behaviour during reactive High Power Impulse Magnetron Sputtering (HIPIMS) has been investigated in detail. Such analysis has been made possible by the recently developed plasma emission monitoring based reactive HIPIMS monitoring and control technology. Hysteresis curves were recorded at frequencies of 300,450 and 600 Hz at an average power of 3.0 kW during reactive HIPIMS of Ti in Ar/O_2 atmosphere. It is shown that the target pulsing parameters, such as frequency, pulse voltage, and duty cycle do affect the overall shape of the hysteresis loop. Analysis of the hysteresis behaviour at different target pulsing parameters reveals how different regions of the hysteresis loop are affected by different pulsing parameters. The outcomes of this work demonstrate trends and explain relationships between the pulsing parameters and the hysteresis behaviour. Although the overall picture is rather complicated, it is quite clear that the hysteresis effect is induced by the same processes as in direct current magnetron sputtering, while the influence of the reactive ion implantation oxidation mechanism appears to be far more significant in reactive HIPIMS.