Modelling of target effects in reactive HIPIMS

Abstract

In reactive High Power Impulse Magnetron Sputtering (HIPIMS) of oxides, target effects such as reduced surface oxidation during pulse off time, increased implantation of reactive gas due to the higher discharge voltage as compared to normal DC sputtering, and enhanced target cleaning during on time are considered to be responsible for the differences compared to reactive DC sputtering. These effects are assumed to cause changes in the target oxide coverage and hence lead to the hysteresis shifts observed in experimental studies. In this contribution, the target processes are simulated using the binary collision approximation code TRIDYN. Using an Al target sputtered in Ar+O2 mixture as a model system, a range of pulse configurations is simulated for different oxygen partial pressures. The results indicate that the target effects alone are not sufficient to explain the observed shift of hysteresis and its frequency dependence.