Silicide formation explains the trend in the crystallization time at low pO2. In principle, the scavenging process, followed by YSZ crystallization, should be fastest in the most oxygen deficient conditions, i.e. when Y and Zr do not oxidize in the plasma and regrowth of the silicon oxide due to oxygen from the background gas is limited. Instead, increased crystallization times were observed in the most oxygen deficient conditions, which can be caused by competition between silicide formation and YSZ crystallization at the silicon-YSZ interface. In the higher pO2 regime, the crystallization time increased with increasing pO2. For both the total pressures of 2*10−2 and 1*10−1 mbar, the increase occurred in the regime where the plasma started to oxidize. Due to this partial oxididation, the scavenging possibility per Zr or Y atom was lower, meaning more YSZ was needed to break down the silicon native oxide.