from the conferences organized by TANGER Ltd.
Anodic alumina in both of its forms – a barrier type and a porous type – has received numerous studies and practical applications. Its potential could be further increased with the recent development of aluminium thin film sputter-deposition technologies. Most of the research has been performed towards Al foil anodizing; however in case of Al thin films the important knowledge is missing. In this study we have investigated the influence of the Al film structure and morphology on the electrochemical response during aluminium anodizing. Various Al thin films were prepared via an ion beam deposition, a magnetron sputter-deposition and a thermal evaporation. The films were then anodized in a barrier-type-giving electrolyte to various final potentials. The as prepared and anodized films were characterized by scanning electron microscopy and stylus profilometry to reveal the effect of the surface morphology on the anodizing behavior and dielectric breakdown in the anodic films. The breakdown potential was found to be typical for all the films tested, although being greatly dependent upon the initial film surface morphology. A model for explanation of the phenomena observed has been developed and justified experimentally.
Keywords: Anodizing, aluminium, anodic alumina, thin films, electric breakdown© This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.