Preparation of Anodic Aluminum Oxide Masks with Size-Controlled Pores for 2D Plasmonic Nanodot Arrays

Figure 2

Schematic illustrations depicting the two-step wet etching process. FE-SEM images show the AAO layer prepared in the pore opening process using the method: (a) the second anodization for 4 min, (b) the first chemical wet etching for 10 min, (c) the bottom part of the AAO layer after dissolving the remaining aluminum substrate in a saturated HgCl₂ solution, and (d) the AAO layer with through pores after the second wet etching for 11 min.