Measurement of the pore sizes for anodic aluminum oxide (AAO)

A new method for the measurement of pore size of the porous-type anodic aluminum oxide (AAO) using atomic force microscopy (AFM) is proposed. The measurement of the pore size by AFM makes no damage to the specimen. AAO film can be referred as a nanohoneycomb structure because the pore shape of AAO is like the honeycomb structure and its pore size is in the nanometer scale. To measure the pore sizes from AFM images, it is assumed that the top surface of AAO is not etched much in the pore widening process. It is because the etching rate of the top surface is very slow due to the mechanical packing stress in the middle of the pore wall of AAO. The pore sizes from AFM images showed good agreement with those from SEM images.