0000000000291567
AUTHOR
Indra Apsite
Ultrathin Anodic Aluminum Oxide Membranes for Production of Dense Sub-20 nm Nanoparticle Arrays
We present a systematic study of membrane structure (pore diameter and arrangement) in anodized aluminum oxide (AAO) layers obtained by anodization voltages 8-20 V in sulfuric and 15-40 V in oxalic acid electrolyte solutions. Anodization of bulk aluminum in sulfuric acid at 10 V potential was found to be optimal for production or ultrathin freestanding membranes with pore diameter in sub-20 nm range. The developed process with slow electrochemical reaction results in AAO membranes with thickness below 70 nm. The minimum required time for formation of continuous AAO membrane was determined and influence of electrolyte concentration on pore diameter in membrane after barrier layer removal ana…
Optical properties of thin metal films with nanohole arrays on porous alumina–aluminum structures
A multilayer system is formed by the deposition of a 10–35 nm thin Au or Ag film with 18–25 nm diameter holes on 75–280 nm thick layers of porous anodized aluminum oxide (AAO) supported by a bulk sheet of aluminum. We present a detailed study of system parameters, which influence the optical response, including the porosity, metal layer thickness and crystallographic orientation of the Al substrate. The spectral properties are mainly governed by the interference of the reflections from the Al substrate and the thin metal film separated by the AAO layer. An enhanced plasmonic attenuation component near 650 nm for the Au films with holes can be observed when the interferometric anti-reflectio…
Fabrication of ultra thin anodic aluminium oxide membranes by low anodization voltages
Formation of ultrathin anodised aluminium oxide (AAO) membranes with high aspect ratio by Al anodization in sulphuric and oxalic acids at low potentials was investigated. Low anodization potentials ensure slow electrochemical reaction speeds and formation of AAO membranes with pore diameter and thickness below 20 nm and 70 nm respectively. Minimum time necessary for formation of continuous AAO membranes was determined. AAO membrane pore surface was covered with polymer Paraloid B72TM to transport it to the selected substrate. The fabricated ultra thin AAO membranes could be used to fabricate nanodot arrays on different surfaces.