Researchers have developed a low-cost, low-power computer memory that could put terabyte-sized thumb drives in consumers' pockets within a few years.
Thanks to a new technique for manipulating charged copper particles at the molecular scale, researchers at Arizona State University say their memory is, bit-for-bit, one-tenth the cost of – and 1,000 times as energy-efficient as – flash memory, the predominant memory technology in iPhones and other mobile devices.
"A thumb drive using our memory could store a terabyte of information," says Michael Kozicki, director of ASU's Center for Applied Nanoionics, which developed the technology. "All the current limitations in portable electronic storage could go away. You could record video of every event in your life and store it."
The new memory technology – programmable metallization cell (PMC) – comes as current storage technologies are starting to reach their physical limits. At the tiny scale envisioned for new devices, flash memory becomes unstable. The physical limits of flash are already being approached, and could be reached in the near future, which could slow product development for portable device makers like Apple and Sandisk.
PMC memory stores information in a fundamentally different way from flash. Instead of storing bits as an electronic charge, the technology creates nanowires from copper atoms the size of a virus to record binary ones and zeros.
In research published in October's IEEE Transactions on Electron Devices, Kozicki and his collaborators from the Jülich Research Center in Germany describe how the PMC builds an on-demand copper bridge between two electrodes. When the technology writes a binary 1, it creates a nanowire bridge between two electrodes. When no wire is present, that state is stored as a .
The key enabling technology for the memory is nano-ionics, a field that focuses on moving and transforming positively charged atoms. In PMC memory, the charged atoms, or ions, are harnessed by applying a negative charge, which transforms them into copper atoms lined up to form nanowires.
Kozicki says the process is like condensing a crystal from a solution, except that the process is almost infinitely reversible. If the PMC is fed a positive charge, the copper atoms return to their previous free-floating state, and the nanowires disassemble.
Kozicki says the technology can be built from materials commonly used in the memory industry, which should help keep manufacturing costs down.
The memory industry has already taken an interest. Three companies, Micron Technology, Qimonda and Adesto (a stealth-mode startup) have licensed the technology from Arizona State's business spin-off, Axon Technologies.
Kozicki says the first product containing the memory, a simple chip, is slated to come out in 18 months.
Market-research firm iSuppli projects the flash-memory market growing from $20 billion in 2006 to $32 billion in 2011. Mark DeVoss, a senior analyst in flash memory at iSuppli, says a lot of companies are gunning for a share of that $12 billion in growth, but it's hard to handicap the likely winners.
"There's a lot of elegant technologies," DeVoss says. "But you have to be able to scale it down and deliver a low cost-per-bit."
Kozicki's licensees believe the technology will deliver the outsize improvements that could drive the memory mainstream.
"No other technology can deliver the orders-of-magnitude improvement in power, performance and cost that this memory can," says Narbeh Derhacobian, CEO of Adesto, who previously worked at AMD's flash-memory division.
Adesto has received $6 million from Arch Venture Partners and additional funding from Harris & Harris, a venture firm specializing in nanotechnology.