Fabrication of nanoscale zero-mode waveguides using microlithography for single molecule sensing

We present a novel approach to the fabrication of zero-mode waveguides (ZMWs) using inexpensive processing techniques. Our method is capable of rapid fabrication of circular nanoapertures with diameters ranging from 70 nm to 2 mu m, allowing us to perform a detailed characterization of the dependence of the fluorescence emission on the waveguide diameter. We also validated the use of the fabricated ZMWs by detecting single molecule binding events with a signal-to-noise ratio of ten.