Growth of Amorphous Ti–Si–O Thin Films by Aerosol CVD Process at Atmospheric Pressure

We present the deposition of amorphous thin films by an aerosol chemical vapor deposition process at atmospheric pressure. We used di-acetoxi–di-butoxisilane, tetrabutoxysilane, and titanium(IV) -butoxide as precursors, and the deposition temperatures ranged from 475 to 675°C. During the deposition process a chemical reaction between the different precursors took place. We found a synergetic mutual influence of the precursors and a coupled activation of the growth process between Ti and Si. The obtained thin films were characterized by various techniques: scanning electron microscopy, atomic force microscopy, X-ray diffraction, Raman spectroscopy, transmission electron microscopy, infrared spectroscopy, ellipsometry, and X-ray photoelectron spectroscopy. Our films were amorphous mixtures with a refractive index between 1.45 and 2.1 depending on the ratio in the films. We established a correlation between the X-ray photoelectron spectroscopy results and the refractive index of the films, allowing us to control the film composition as a function of the deposition conditions.