Researchers at the University of Sheffield have devised an innovative technique to join together nanoscale-objects.

The joining technique, known as nanowelding, can be used to take the manufacturing of technology, such as brand new sensors and ultra fast computer chips, to a new level.

Dr Yong Peng and Dr Beverley Inkson, from the Department of Engineering Materials, have developed a new way to weld individual nano-objects using tiny blobs of metal solder, less than 250 atoms across.

Nanoconstruction using nanoscale solder. (a) Touching nanowires can be joined using a nanoscale volume of solder melted from a sacrificial nanowire. (b) The word "NANO" written at the nanoscale by individual 55-nm-diameter gold nanowires.
Image credit : American Chemical Society

Nanowelding is becoming increasingly important for nanotechnology applications such as nanosensors and nanoelectronics. Most manufactured objects, from aeroplanes to electronic chips, require complex joining processes to link materials into a single working structure. However, most everyday joining techniques cannot be applied at the nanoscale, as nano-objects are easily destroyed by heat.

The new technique works by heating a tiny metal wire which is in contact with the materials to be joined. The solder wire melts and flows onto the join. The welding can be watched in real-time inside an electron microscope, allowing the choice of exactly where, and how much, nanosolder is deposited.

Dr Inkson said: "Our research findings represent an exciting breakthrough in nanowelding. Previous research has concentrated on developing ways to make individual nanosclale objects, but not many ways to join them together. Our new technique is particularly exciting because the chemistry, strength and conductivity of the join can be engineered at the nanoscale."

The research findings, published in the Journal, Nano Letters, are part of the EPSRC Basic Technology Nanorobotics Programme. The NanoLAB Centre at the University was awarded one of six EPSRC Basic Technology Translation awards (750K) to develop this work with industry from July 2009.

This research was published in the December 10, 2008, online edition of Nano Letters .

Citation: Nano Letters , ASAP Article, DOI:10.1021/nl8025339

Source: University of Sheffield via Sheffield Telegraph /...