IBM researchers say they've made progress in showing how carbon nanotubes could some day replace silicon in the guts of microprocessors.
In a research paper published this month in Nano Letters, IBM researchers found that carbon nanotube transistors smaller than 10 nanometers outperformed silicon devices. These transistors also operate at very low voltage, which means they promise processors that operate with low power consumption.
The experiments researchers performed were designed to test the theoretic performance of carbon nanotube transistors, rather than develop new manufacturing processes. But the finding could be significant in the ongoing pursuit of smaller transistors for more computing power.
Carbon nanotubes are hollow cylinder shaped structures made of connected carbon atoms that have been touted for years as a potential semiconductor material. Producing carbon nanotubes at scale is one technical challenge to developing computing devices with them. The overwhelming weight of the semiconductor industry infrastructure is based on silicon as well, making introduction of new materials difficult.
Where carbon nanotubes can be significant is miniaturization, John Rogers, professor of materials science at the University of Illinois at Urbana-Champaign, told Technology Review in an article published last week. Intel last year announced it will start using three-dimensional transistors for its 22-nanometer process, a move designed to operate at lower voltage and avoid leakage of current that occurs at this very small scale.
IBM found that carbon nanotube transistors at under 10 nanometers outperformed silicon on speed and power better than models had predicted. That means carbon nanotubes warrant further research for use as transistors, the building block of microprocessors, IBM said. "The superior low-voltage performance of the sub-10 nm CNT transistor proves the viability of nanotubes for consideration in future aggressively scaled transistor technologies," according to a summary of the paper in Nano Letters.