University of Illinois researchers have developed a way to heal gaps in wires too small for even the world's tiniest soldering iron. Led by electrical and computer engineering professor Joseph Lyding and graduate student Jae Won Do, the Illinois team published its results in the journal Nano Letters.
Carbon nanotubes are like tiny hollow wires of carbon just 1 atom thick - similar to graphene but cylindrical. Researchers have been exploring using them as transistors instead of traditional silicon, because carbon nanotubes are easier to transport onto alternate substrates, such as thin sheets of plastic, for low-cost flexible electronics or flat-panel displays. Carbon nanotubes themselves are high-quality conductors, but creating single tubes suitable to serve as transistors is very difficult. Arrays of nanotubes are much easier to make, but the current has to hop through junctions from one nanotube to the next, slowing it down. In standard electrical wires, such junctions would be soldered, but how could the gaps be bridged on such a small scale?
Now, the group is working to refine the process. "We think we can make it even better," Lyding said. "This is the prelude, we hope, but it's actually quite significant."