Jun 5, 2008
Creating large-area nanoscale array patterns by nanosphere lithography
Two-dimensional (2D) nanostructure patterns have extensive applications in photonic devices, nanoelectronics, electrochemical devices, biosensors, catalysts and high-density magnetic recording devices. Commonly used patterning techniques, such as photolithography, electron-beam lithography, focused ion beam lithography and scanning probe microscopy (SPM) lithography have limitations on the fabrication of 2D nanostructures. It remains a challenge to develop low-cost, high-throughput, high-resolution techniques for fabrication of large-area (wafer-scale) 2D nanostructure array patterns with controlled feature size, shape and pitch.
Nanosphere lithography (NSL) is a simple, inexpensive, high-throughput, alternative routine for creating periodic nanostructure arrays. However, most of the sphere templates that were reported in previous literature have shown a well-ordered arrangement of nanospheres only in a small area of domain, which makes it difficult to create large-area nanoscale array patterns. Nick Wu’s group at West Virginia University recently improved the nanosphere lithography method and demonstrated a low-cost, high-throughput, high-resolution technique for fabrication of large-area (wafer-scale), high-quality nanostructure array patterns with controlled feature size, shape and pitch. They have combined the nanosphere lithography technique with electrodeposition processing to devise a facile nanopatterning approach. By utilizing this approach, they have fabricated a nanowell polypyrrole array pattern and a gold nanohemisphere array pattern. This work was recently published in Nanotechnology.
Their nanopatterning approach can be extensively used for nanodevice fabrication. They have demonstrated that the fabricated pattern can function as a nanoelectrode array (NEA). NEAs attract a lot of attention because they bring intriguing benefits over conventional macroelectrodes, including enhanced mass transport, lowered detection limit, improved signal-to-noise ratio, increased temporal resolution and the ability to make spatially resolved chemical measurements.
About the author
Dr Nianqiang (Nick) Wu is assistant professor at the Department of Mechanical and Aerospace Engineering in West Virginia University, US. He is a member of WVNano Initiative. Dr Huaqing Li is a postodoctoral fellow in Nick Wu's group.