Nano rapid prototyping advances

Rapid prototyping -- using lasers to harden liquid plastic into three-dimensional shapes -- has been around for a couple of decades, but lately researchers have been working to scale the process down to the realm of nanotechnology.

Researchers from University College London and the University of Cambridge in England, and Superior Technical Institute in Portugal have found a way to use near-field light to make features as small as 160 nanometers, which is about six times narrower than an E. coli bacterium. A near-field light source can focus narrowly, hardening minuscule amounts of plastic, because it resides closer to a surface than the span of the wavelength of and light it uses.

The researchers exposed portions of a soluble polymer to ultraviolet light to make those portions insoluble, and dissolved the remaining polymer to leave tiny patterns.

The method could eventually be used to make rapid prototypes of nanoscale photonics devices that guide lightwaves, light sources smaller than a red blood cell, and plastic electronics that store data and compute.

The method will be ready for practical prototyping in five years, according to the researchers. The work appeared in the January 27, 2003 issue of Applied Physics Letters.