A team of academics at MIT has unveiled the world’s most advanced chip yet that’s made from carbon nanotubes—cylinders with walls the width of a single carbon atom. The new microprocessor, which is capable of running a conventional software program, could be an important milestone on the road to finding silicon alternatives.

The electronics industry is struggling with a slowdown in Moore’s Law, which holds that the number of transistors that can be packed on a silicon processor doubles roughly every couple of years. This trend is facing its physical limits: as the sizes of the devices shrink to a few atoms, electrical current is starting to leak from the metallic channels that shuttle it through transistors. The heat that’s released saps semiconductors’ energy efficiency—and may even cause them to fail.

Carbon nanotubes could be the perfect solution. Not only are nanotube transistors faster than silicon ones, studies have found that chips made from nanotubes could be up to ten times more energy efficient. This efficiency boost could significantly extend electronic gadgets’ battery life.

Researchers have been working on alternative chips involving the molecules for decades, but manufacturing headaches have kept the processors stuck in research labs. In a paper published in Nature, the MIT team says it has found ways to overcome some of the biggest hurdles to producing them at scale.

Mixed up

One problem is that when carbon nanotubes are made, they come in two types mixed together: the first are semiconductors that are perfect for creating integrated circuits, but the second conducts electrical current like a wire, which sucks more power and can even undermine a circuit’s performance. To make the chips economically viable, a cost-effective way to minimize the impact of the latter group is needed.

Another problem is that to make the chips, a uniform monolayer of carbon nanotubes needs to be deposited over a wafer. But this has proven hard to do because nanotubes have an annoying tendency to bunch together. A bundle of them that lands on a transistor can knock it out of action.