A revolutionary new type of digital storage memory, funded since its infancy by the Office of Naval Research, recently reached a milestone and transitioned into the testing and debugging phase of its development. This new technology -- Vertical Giant Magnetoresistance Random Access Memory, or VRAM -- was conceived and demonstrated by the Naval Research Laboratory and Carnegie Mellon University.
"The technology is a direct product of a basic research program supported for many years by ONR to explore new materials and concepts in magnetism, which is a strength of ONR programs," said Dr. Larry Cooper, the ONR program officer who funds the work.
VRAM memory has the potential to replace all mechanically driven storage media, including computer hard drives and compact discs. The new goal is a technology, which will produce a 100 to 1,000-fold increase in the storage capacity over semiconducting memory. The dynamic RAM used by today's personal computers must continually refresh their memory cells or all of the information contained in them would be lost. A static form of RAM exists that does not need constant refreshing, but it is expensive and consumes a lot of chip area.
VRAM dramatically reduces the need for transistors, leading to lower cost, and retains information without continual refreshing, reducing the power requirement. The information contained in the memory cells remains there, even when the power is turned off. The researchers estimate that VRAM technology will also increase memory access speed by a factor of 10. The high-density, non-volatility, radiation-hardness and low-power attributes of VRAM make it well suited to space, avionics, and shipboard applications. In addition to its freedom from moving mechanical parts, the technology is particularly advantageous when a component or system, once implemented, is difficult or impossible to retrieve.
In 1999, ONR awarded a contract to Nonvolatile Electronics, Inc., under the Navy Small Business Program, to develop the enabling technology for VRAM. The Minnesota-based company recently met its Phase I goals, which included completing a preliminary circuit design and outlining a process for fabricating integrated VRAM memory arrays. Under the Phase II portion of the contract, the company will design the circuits, develop processing technology, fabricate, test and debug the technology, then produce and demonstrate a prototype VRAM array fully integrated with silicon-based electronics.
"We're pleased at the progress Nonvolatile Electronics has made in bringing this technology closer to a manufacturing environment," Cooper said. "Ultimately, we believe it will be possible to produce vertical giant magnetoresistance memory cells on existing silicon processing lines with only minor modifications."
The total annual market for nonvolatile solid-state memory is estimated at more than $10 billion, with this new technology addressing a significant portion of that market.