Fabrication of Ordered Arrays of Anodic Aluminum Oxide Pores with Interpore Distance Smaller than the Pitch of Nano-pits formed by Ion Beam Etching

Abstract

We investigated a method for preparation of ordered nanopore arrays with the interpore distance of 60 nm by guided self-organization of anodic aluminum oxide with a prepatterned array of pits in the starting Al film. An ordered triangular array of 100 nm-pitch pits was formed on Al film by ion beam etching through an electron beam lithography fabricated mask, and then it was used as a guide for formation of anodic aluminum oxide pores. We found it was possible to reduce the interpore distance to 1/√3 of the pitch of the pits by the appropriate choice of the parameters of ion beam etching and anodization voltage.