Conceptual model for spray pyrolysis mechanism: fabrication and annealing of titania thin films

The present work presents a comprehensive model of both processes and outcomes of the spray pyrolysis mechanism, which is based on wide-ranging experience gained from experimentation involving a range of parameters. The deposition temperature and initial droplet size are the main parameters controlling film properties, including mineralogy, surface morphology, thickness, and bonding; the effect of annealing on these properties also is considered. The model is supported experimentally through the processing of films aerosol and ultrasonically spray pyrolyzed at 350A degrees C, followed by annealing for 12 h at 500A degrees C in air. Assessment of the mineralogy, chemical bonding, and crystallinity/residual stress of the films involved glancing-angle X-ray diffraction and laser Raman microspectroscopy, Fourier transform infrared spectroscopy, and crossed polarizers with an optical microscope, respectively.