Structural, Surface and Optical Analysis of Al2O3 Thin Film on Al Substrates Prepared by Chemical Vapor Deposition Method

Abstract

Aims: Synthesis of Aluminium oxide (Al2O3) thin films on Al substrates by CVD method and study their structural parameters and surface properties for various processing time. Study Design: Synthesized thin film samples were post processed with various temperature. The structural and surface properties were analyzed by XRD technique and FESEM method to understand the influence of processing time and also the temperature. Place and Duration of Study: Nano Optoelectronic Research Laboratory, School of Physics, Universiti Sains Malaysia, Penang 11800, Malaysia, between December 2013 and July 2014. Methodology: Aluminium oxide (Al2O3) thin films were synthesized on Al substrates by CVD method and manipulating the deposition time for their structural evaluation using XRD spectra. The surface and optical properties were analyzed by FESEM and FTIR spectra respectively. Results: Polycrystalline structure was noticed with (025) phase as dominated in Al2O3 structure. From the XRD spectra, the observed crystallite size was increased with process time for (025) oriented phase and also noticed the average crystallite size was under 100 nm. The observed dislocation density was high for the film deposited at 20 mins duration for both (201) and (025) phases. The CVD synthesized Al2O3 thin film had bubble type structure on their surface irrespective to the process times and also annealing. Conclusion: Al2O3 thin film was successfully deposited by CVD at low operating temperature. Post processing (annealing) was not supported to improve Al2O3 growth on Al substrates and also their structural properties.