Self-Ordered Nanopore Arrays with 300–400 nm Interpore Distances Formed by High Field Accelerated Mild Anodization

Abstract

High field accelerated mild anodization was used to fabricate self-ordered nanoporous alumina arrays. The phosphoric acid with various concentrations was used in a wide range of anodization voltages. Two different temperatures for both sides of the samples were employed to maintain a mid level of current density during the anodization process. The interpore distances were seen to vary from 300 to 400 nm when the anodization voltages changed from 150 to 190 V. A nonlinear-inverse relation between electrolyte concentrations of phosphoric acid and anodization voltages was found in the optimum self-ordering conditions. Similar to the hard anodization, the ratio of interpore distance to voltage was 2 nm/V in high field accelerated mild anodization technique.