Growth Mechanism of TiO(2) Nanotube Arrays in Nanopores of Anodic Aluminum Oxide on Si Substrates by Atomic Layer Deposition

Abstract

In this study, we combined atomic layer deposition and anodic aluminum oxide (AAO) on a silicon substrate and developed self-aligned TiO(2) nanotube arrays. We studied the growth mechanism of TiO(2) nanotubes on the inner wall of AAO at 100 and 400 degrees C. We found that at 100 degrees C, TiO(2) grew in a layer-by-layer manner. Therefore, it can be grown into TiO(2) nanotube arrays with very thin walls. However, at 400 degrees C, TiO(2) needs to first form a 2.5-nm amorphous layer, before becoming crystalline TiO(2) via a phase transformation, and growing into crystalline TiO(2) nanotube arrays along the preferred plane {101} by means of a space-limited growth mechanism. (C) 2011 The Electrochemical Society. [DOI: 10.1149/1.3528939] All rights reserved.