Study on Wet Etching of AAO Template

Abstract

The highly ordered anodic aluminum oxide (AAO) template was prepared with two-step anodization. The AAO template was carried out wet etching process using a mixture of phosphoric acid and chromic acid, NaOH, and H3PO4 solutions. The relationship between mass loss of AAO template and etching time was studied. The results indicate that 3 wt % H3PO4 solution is a more mild and effective etchant comparing with these etchants, and the mass loss is linear with etching time. SEM investigations show that alumina nanowires were obtained with high yield by etching AAO template. And, the growth of alumina nanowires was closely related to the etching time.