Optical characterization of self-ordered porous alumina membranes of various thicknesses

We present the fabrication and optical characterization of self-ordered porous alumina membranes (PAM). The samples were fabricated by using a two-step anodization process in 0.3 M oxalic acid at 40 V and 20°C. PAMs of different thickness (9 μm, 24 μm and 45 μm) were obtained by applying different anodization lengths. The morphology of the PAMs was examined using a Scanning Electron Microscope in order to estimate their thickness and porosity. The optical transmission spectra of such PAMs of different thicknesses were measured by using UV-VIS spectrometer in the range of 300-1000 nm. The refraction index and the extinction coefficient for the studied range were determined from the fitting of the measurements. © 2007 WILEY-VCH Verlag GmbH & Co. KGaA.