Structural and optical characterizations of porous anodic alumina–aluminum nanocomposite films on borofloat substrates

Abstract

Structural and optical properties of the porous anodic alumina (PAA)-aluminum (Al) nanocomposite and the PAA-nanostructured films on borofloat substrates are studied. The films are fabricated by the anodization of 170-to 200-and 295-to 330-nm-thick Al sputtered onto the borofloat. The anodization process is stopped at different times in order to form the PAA-Al nanocomposite films with different layer thicknesses. Then, the pore widening is applied to 189-to 210-and 430-to 495-nm-thick PAA films in 5-and 10-min intervals, respectively. The structural properties of the films are characterized by a scanning electron microscopy. The nanocomposite films are also characterized optically by total reflection and directional transmission measurements in the wavelength range between 250 and 800 nm. Our results indicate that controlling the thicknesses of both Al and the PAA layers by anodization time and the morphology of the nanostructures by chemical etching duration in the PAA layer provides unique PAA-Al nanocomposite films with desired optical properties.

Formation of Nanoporous Anodic Alumina by Anodization of Aluminum Films on Glass Substrates

“…There are many reports on studying the formation of PAA from deposited Al films on glass [ 11 , 14 – 19 ]. Analysis of published data shows that during the formation of PAA from aluminum film on any substrate, not only the process of anodic oxidation affects the outcome but also the way of deposition of aluminum films [ 20 ], the impurity in the film [ 21 ], the heat treatment of aluminum film [ 22 ], the thickness of Al film [ 23 ], and the presence of a conductive underlayer on an insulating substrate [ 17 , 18 ].…”