Self-aligned tantalum oxide nanodot arrays through anodic alumina template

Abstract

A novel strategy for fabricating the ordered nanodot arrays of tantalum oxide with anodic alumina film is proposed to serve the template. Anodic oxidation of Al on TaN film has been performed in oxalic acid and sulfuric acid electrolytes at various applied voltages for porous alumina formation. Anodising reaction proceeds in the sequence of growth of porous anodic alumina when the aluminum layer is consumed up to the underlying TaN, and the growth of tantalum oxide under the bottoms of the alumina pores occurred simultaneously. The nanostructure of the nanodot arrays was studied by scanning electron microscopy, and the chemical composition of nanodots was analyzed by X-ray photoelectron spectroscopy. The nanodots are composed of nonstoichiometric TaOx. The nanodot diameter demonstrated here ranges between 15 nm and 70 nm and density ranges between 10(11) /cm(2) and 10(10)/cm(2). (c) 2006 Elsevier B.V. All rights reserved.