Preparation of Anodic Aluminum Oxide Membrane for the Template Synthesis of Semiconductor Nanowires

Chang Hyun Ko, Sung-Youl Park, Kwang Bok Yi, Jong-Ho Park, and Jong-Nam Kim. Chemical Process Research Center, Korea Institute of Energy Research, 71-2 Jang-Dong, Yuseong-Gu, Daejeon, South Korea

Synthesis of nanostructured semiconductors have attracted much attention due to their distinctive electrical, optical and catalytic properties. Their properties mainly come from their high surface to volume ratio and quantum confinement effect. Many researchers have synthesized nanostructured semiconductors by various types of methods, such as, pyrolysis in solution and template synthesis, to find out specific properties. However, not only synthesis, but also fabrication of nanostructured semiconductors should be considered for the practical applications. Thus, template synthesis method seems to be superior to solution phase synthesis method because formation and fabrication of nanostructured semiconductor might be achieved simultaneously with proper templates located on adequate place. As a preliminary study for this purpose, anodic aluminum oxide (AAO) with membrane type, in which pores are directly connected and opened in both sides were prepared by anodization of aluminum plate using oxalic acid as electrolyte. Depending on the concentration of oxalic acid and anodization temperature, pore diameters of AAO membrane were controlled from 10 to 100 nm. In this pore, various types of semiconductors, such as zinc sulfide, zinc oxide, and silicon were selectively incorporated by gas phase deposition methods. Reducing the deposition rate of semiconductor is the critical factor for the formation of nanowires in the pores.