A simplified anodized aluminum oxide (AAO) nano-template fabrication process was developed in this study, which can be suited for the large area device applications. The pores of various sizes and depths were realized from the thin (less than 1 μm) aluminum film deposited on the sapphire substrate. The optimum morphological structure was obtained by adjusting the applied voltage, types of acid solution, its concentration and temperature which has evolved after two phases of anodization followed by chemical etching. The Ar plasma pre-treatment method was developed and applied to improve the surface roughness of thin aluminum film without severely sacrificing the deposited layer thickness.