Instant-on computers. Laptops that eat up less battery power. Cell phones that store a selection of movies. Those are the benefits Nantero hopes to bring to consumers by creating a new type of computer memory that combines the speed and density of SRAM and DRAM chips with the permanent storage capacity of flash memory. The Woburn, MA-based company is building computer memory with carbon nanotubes, which it says will provide advantages that other memory technologies can’t.
“There’s a growing need for more and more memory in portable devices,” says Greg Schmergel, CEO of Nantero. “In a few years, it’ll be common to talk about how many terabytes you have.”
That’s the vision that Schmergel has been pursuing since founding Nantero in 2001 along with a pair of chemistry Ph.D.s from Harvard, Thomas Rueckes and Brent Segal. Since then, the company has amassed 60 employees, 50 patents (and another 100 pending), and $31.5 million in funding from investors including Charles River Ventures, Globespan Capital Partners, Draper Fisher Jurvetson, and Stata Venture Partners. The company also has growing revenues from licensing its technology (more on that in a moment) and from a partnership with Brewer Science of Rollo, MO, which manufacturers carbon nanotubes for electronics manufacturers to use in designing and building their own products.
Nantero is working on what it calls NRAM, or nonvolatile random access memory; the technology was invented by Rueckes, who’s now the company’s CTO. Like flash memory, which is common in digital cameras, NRAM will hold data indefinitely without drawing any power, but can easily be rewritten when the power’s turned on. But it will have far more storage capacity and will work much faster.
NRAM makes bits out of pairs of carbon nanotubes. One nanotube is fixed to the surface of the chip, another stands up perpendicular to the first. Give one nanotube a negative charge and the other a positive charge, and the upright nanotube bends down and touches the other. Because of physical forces at this tiny scale, measured in billionths of a meter, the two nanotubes stick together and stay that way, unless a new pulse of electricity gives them the same charge and they repel one another. The closed and open pairs represent the ones and zeros of digital data.
“You’re moving a few hundred carbon atoms over distances measured in billionths of a meter,” Schmergel says. It takes only a little power and a short time to do that, making the data-writing process fast and easy. The speed and power advantages alone make NRAM superior to today’s flash memory, he says.
But more important is the fact that NRAM will be able to go