A colloidal lithography route to zero mode waveguides.

Zero mode waveguides (ZMWs) are nano-apertures in a conducting film that enable single-molecule fluorescence measurements in the presence of up to micromolar concentrations of probes in solution. Here, we report on a method for fabricating ZMWs using a self-assembled mask made of polystyrene microspheres, thermal annealing, and metal evaporation. Data is presented characterizing the performance of these devices. Importantly, this fabrication technique provides a route to fully functional ZMWs without the need for expensive electron beam or deep-UV lithography.