STUDY OF ANNEALING INFLUENCE ON IRO2 THIN FILMS USING ULTRASONIC TECHNIQUE.

Iridium oxide (IrO2) thin films were prepared using sol-gel technique. The prepared films subjected to different annealing temperatures (3000C, 4000C, 5000C, 6000C and 7000C). By using ultrasonic pulse echo technique, ultrasonic attenuation coefficient (α), ultrasonic velocities (longitudinal, CL and shear, CS) and thin film thickness (X) measured. Then elastic moduli (Young?s (E), longitudinal (L), shear (G) and bulk (K)), Poisson?s ratio (v) and micro-hardness (H) were calculated. By optical method, band gap energy (Eg) of the prepared thin films measured. Films? densities (ρ) had known from weights difference. The study showed that the ultrasonic attenuation coefficient, films? densities and Poisson?s ratio increased as the annealing temperature increased while ultrasonic velocities, elastic moduli, thickness, micro-hardness and band gap energy did the contrast. It may be due to molecules mobility and voids variation with respect to annealing temperatures. Therefore, the mechanical properties, band gap energy, density, micro-hardness and thickness of IrO2 thin films were changed.