title: Tailoring morphology in free-standing anodic aluminium oxide: control of barrier layer opening down to the sub-10 nm diameter.
abstract: Free-standing, highly ordered porous aluminium oxide templates were fabricated by three-step anodization in oxalic, sulfuric or phosphoric acid solutions, followed by dissolution of the aluminium substrate in HgCl(2). Opening of the pore bottoms on the barrier layer side of these templates was carried out by using chemical or ion beam etching. Chemical etching is capable of achieving full pore opening, but partial pore opening occurs inhomogeneously. On the contrary, ion beam etching enables homogeneous and reproducible partial pore opening, with the pore size controlled through the etching time. By this method, pore openings as small as 5 nm can reliably be obtained.
authors.affiliation: Center for Materials for Information Technology, University of Alabama, Tuscaloosa, AL 35487-0209, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Gong
authors.forename: William H
authors.initials: WH
authors.lastname: Butler
authors.forename: Giovanni
authors.initials: G
authors.lastname: Zangari
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D004566:Electrodes; D008627:Mercuric Chloride / Q000737:chemistry; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry / Q000648:ultrastructure; D019815:Oxalic Acid / Q000737:chemistry; D010756:Phosphoric Acids / Q000737:chemistry; D016062:Porosity; D013464:Sulfuric Acids / Q000737:chemistry
chemical_list: D010756:Phosphoric Acids; D013464:Sulfuric Acids; D008627:Mercuric Chloride; D019815:Oxalic Acid; C030242:phosphoric acid; D000537:Aluminum Oxide; C033158:sulfuric acid