When you shrink wires down to nanometres in diameter, their resistivity normally grows exponentially — a trade-off which many have predicted will be Moore’s Law’s undoing soon. But a new, single-atom thick wire could change that.
Over time the copper tracks on microchips have been shrinking and the resulting massive increases in resistance are what have been threatening Moore’s Law, by slowing down progress in chip manufacturing.
But now a team of researchers have created low-resistivity nanowires by stringing together individual atoms of silicon, reports Scientific American. These wires are four atoms wide and one atom thick and the researchers have shown that their resistivity doesn’t vary with size. That basically means Ohm’s law holds for these nanowires, physics fans.
But how the hell does it work? The secret ingredient is phosphorus. The researchers include a little, evenly spaced along the wires, as it donates electrons to the silicon crystal, in turn promoting electrical conduction. Hey presto, wires that scale perfectly to the nano-scale.
And how do they help? Well, it turns out that the wires have the carrying capacity of copper, which means they could be used to replace the printed copper lines in microchips. Moore’s Law is saved! For a while, anyway. [Scientific American]
Image: Bent Weber