All films were grown in a TSST PLD chamber with in situ RHEED (STAIB). A 248 nm KrF laser (Coherent LPXpro) was used for ablation from a polycrystalline YSZ target. The base pressure of the PLD chamber was in the 10−8 mbar range. For low partial oxygen pressures, the oxygen flow was regulated with a needle valve, while the flow of Ar was regulated with a mass flow controller. The substrates were heated via laser heating. The deposition parameters are summarized in Table 1. Samples examined with in situ XPS were cooled down in vacuum, while the thicker samples examined with XRD were cooled down in 100 mbar O2.Table 1Parameters for YSZ deposition.Substrate temperature (°C)800Heating rate (°C)50Cooling rate (°C)20Fluency (J/cm2)1.9Spot size (mm2)2.4Laser repetition rate (Hz)VariedTotal background pressure (mbar)0.02 or 0.1Partial oxygen pressur (mbar)VariedTarget-substrate distance (mm)50The conditions which were varied are described in the results section.