Facile and scalable patterning of sublithographic scale uniform nanowires by ultra-thin AAO free-standing membrane

Creating sublithographic scale uniform nanowires for large area is an important issue for nanowire-based various device applications. Although anodic aluminium oxide (AAO) membrane is a promising technique, existing attached AAO membrane mask methods have not been able to fabricate such small nanowires for large areas due to difficulties on transferring a thin membrane. Here we demonstrate a facile and scalable methodology to fabricate sublithographic scale uniform-sized nanowires by introducing ultra-thin AAO free-standing membrane with a rigid Al frame and a hydrophilic contacting method. The present method allows us to fabricate sub 20 nm nanowires with the standard deviations of 1.1 nm via defining the size and spacing of metal catalysts for nanowire growth. We also show the scalability of the present attached AAO membrane mask method for a 4-inch scale wafer.