“…It has been shown that a large variety of processing possibilities exist to deposit solid, amorphous, metal oxide thin fi lms such as precipitation-based fi lm processing, [27][28][29] for example, spray pyrolysis, sol-gel, or fl ame-spray processing, and vacuum-based techniques, [ 27 , 30 ] for instance, pulsed laser deposition (PLD) or physical vapor deposition (PVD). All processing methods have in common that the amorphous thin fi lms crystallize upon annealing at temperatures above the deposition temperature.…”