A lot has been said about graphene transistors, and how they might one day enable the creation of computer chips that are hundreds of times faster than the current crop of bleeding-edge silicon-based parts. With silicon fast running out of steam and no clear path beyond 14nm, graphene might just be the light at the end of the tunnel. For that to occur, though, we first need to turn graphene into a reliable semiconductor; the world’s greatest chemists and physicists need to get together and work out how to switch graphene off. This is proving to be a lot harder than it sounds — but now, thanks to a fancy effect called negative resistance, researchers at the University of Riverside, California (UCR) may have cracked it. All semiconductors, whether we’re talking about silicon or a fancy III-V material such as gallium arsenide, owe their semiconducting properties to their bandgap. A bandgap is essentially a certain energy difference (measured in electronvolts), up to which electrons cannot flow across a material. As long as the voltage difference remains below a certain level, the material acts as an insulator. At a certain point, though, the energy difference reaches a point (the band gap) where  there’s enough energy to knock

The post Graphene transistors based on negative resistance could spell the end of silicon and semiconductors has been published on Technology Org.