Nano-Soldering Process for Better Electronic Device Performance

Researchers have been exploring using carbon nanotubes 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 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. University of Illinois researchers have now developed a simple and self-regulating nano-soldering process. "It occurred to me that these nanotube junctions will get hot when you pass current through them," said electrical and computer engineering professor Joseph Lyding, "kind of like faulty wiring in a home can create hot spots. In our case, we use these hot spots to trigger a local chemical reaction that deposits metal that nano-solders the junctions." The nano-soldering takes only seconds and improves the device performance by an order of magnitude.