High aspect ratio microstructures on porous anodic aluminum oxide

Abstract

Various technologies have been developed to fabricate high aspect ratio microstructures on planar surfaces. In this work, we present a technology which exploits the highly ordered pore structure of anodic aluminum oxide. Using this technology, we have fabricated 120pm high microstructures with vertical side walls; we estimate millimeter high structures with aspect ratios exceeding 1000: 1 could be achieved.