Patterned ultrathin metal membranes with hexagonally packed sub-50nm nanopore arrays based on hydrophilicity-templated self-assembly monolayer

We report a simple method to fabricate a patterned ultrathin metal membrane with hexagonally arrayed sub-50 nm nanopores based on hydrophilicity-templated self-assembly monolayer (SAM) of polystyrene (PS) nanoparticles. Photolithography assisted hydrophilicity-template defines the membrane pattern, in which the arrayed nanopores are transferred from the hexagonally packed polystyrene nanoparticles by nanosphere lithography. The membrane thickness, depending on the physical vapor deposition process, is as thin as tens of nanometers. By changing the diameter of the original particles, the period of the array can be conveniently controlled. Above all, the nanopore size depends to a great extent on the diameter of shrunk nanoparticles and can be reduced further by uniform coating of parylene. The metal membrane with patterned nanopore array shows great promise in the application of biosensors, nanofiltration and nanofluidic devices.