Dipping technique makes nanotube circuits

Abstract

Supplementing or replacing silicon chips with carbon nanotubes could allow continued improvements in computing performance. But the tubes are tricky to work with. Now a team in China has developed a method to collect the best carbon nanotubes and line them up in a way that will let them build new types of chips (Science 2020, DOI: 10.1126/science.aba5980). Individual carbon nanotubes can be made into transistors, but it’s much easier to make them from groups of aligned tubes. The challenge is in the consistency of the materials. Some carbon nanotubes turn out metallic, so the electron flow won’t easily turn off. And to make a good transistor, they need to be packed densely enough to carry sufficient current. The method developed by Zhiyong Zhang and Lian-Mao Peng at Peking University’s Frontiers Science Center for Nano-optoelectronics sorts the nanotubes so that no more than one in a million is metallic, and