An original method offered by the University of Colorado to reduce the size of circuitry used in the fabrication of nanotechnology equipment such as solar cells and computer chips by zapping a substrate with two different color light beams has been licensed to Heidelberg Instruments.
The patent pending technique uses a high-focus beam of blue light to etch dots and lines of size several thousand times thinner than the thickness of a human hair, to create lithography patterns on any substrate, for example, silicon stated McLeod. He added that following this another beam of ultraviolet light is used to remove the pattern’s edges, thus designing smaller structures.
McLeod and his coworkers utilized a tabletop laser to concentrate high-focus beams of blue light onto monomers or liquid molecules, thus initiating a chemical reaction that bonds the monomers into a polymeric solid that resembles plastic. Concentrating the blue light in a single spot produced a solid, small dot, whereas when the beam’s focus is adjusted to move along the material’s surface, it generates a thin line.
The CU researchers also used another ultraviolet laser concentrated, in the shape of a halo or donut, to surround the blue light. The monomer formation was so designed that it is repressed by the UV light and conversion from liquid to solid is stopped, he said. This repressing effect of UV light hampers the growth of the edges of the spot or line, thus resulting in a final finer structure.
McLeod stated that the new method can be used to manufacture a wide range of nanotechnology equipment such as nanomechanical devices and electronic circuits. He added that the method delivers the potential to reduce transistor circuitry, a process used to manufacture compact, high-power microchips.
Source: http://www.colorado.edu/