The Effect of the Process Conditions on the Synthesis of Zirconium-Aluminum Oxide Thin Films Prepared by Ultrasonic Spray Pyrolysis

Abstract

Zirconium-aluminum oxide thin films with different aluminum/zirconium ratios have been prepared by ultrasonic spray pyrolysis, using metallic acetylacetonates as source materials. The effect of variations of substrate temperature , carrier gas flow rate , and aluminum concentration in the start solution on the ratio, the deposition rate , and refractive index of deposited films is analyzed. The ratio increases when the and ratios increase, but it diminishes as is augmented. Moreover, grows when the deposition parameters are incremented. Refractive index acquires values around 1.85 in all cases. X-ray photoelectron spectroscopy results indicate that the Zr 3d and O 1s core levels shift toward low binding energies when aluminum is incorporated. The location of line Al 2p and its symmetry indicates that aluminum atoms are completely oxidized, forming a ternary oxide with zirconium atoms. Infrared transmittance spectra show small absorption bands related with Zr–O and Al–O bonds in a ternary (ZrAlO) oxide. X-ray diffraction spectra show that all the films containing aluminum are amorphous, except that deposited at the highest . In all other studied cases the films are amorphous. The dielectric constant has values between 11.84 and 20.96 depending on the deposition conditions.