Surface Reaction of Na 0.5 K 0.5 NbO 3 Thin Films in Inductively Coupled BCl 3 /Cl 2 /Ar Plasma

The etch of (NKN) thin film was performed in inductively coupled plasma. It was found that the 1sccm addition (5%) into plasma caused a non-monotonic behavior of the NKN etch rate. The maximum etch rate of NKN was 95.3 nm/min at (1 sccm)/ (16 sccm)/Ar (4 sccm), 800 W ICP power, 1 Pa pressure and 400 W bias power. The NKN etch rate shows a monotonic behavior a s the bias power increases. The analysis of the narrow scan spectra of XPS for both a s-deposited and etched NKN films allowed one to assume ion assisted etch mechanism. The most probable reason for the maximum etch rate can be defined as a concurrence of chemical and physical etch pathways.