Live Science reports that Max Shulaker, one of the creators of the new processor and a doctoral candidate in electrical engineering at Stanford University, California, revealed the design at a September 10 event hosted by the U.S. Military’s research division, the Defense Advanced Research Projects Agency.
The processor uses a 3D structure built around carbon nanotubes, which makes it possible to weave memory chips into the core of the transistor layers of the processor. This reduces the distance between the two elements and can dramatically speed up operation times as a result.
According to Shulaker, developments in ever-faster computers are being held back by memory access restrictions rather than a lack of raw processing power. Because the memory banks are often located a considerable distance away from the processor on a typical motherboard, the CPU can end up waiting to have data returned to it.
This delay becomes particularly noticeable when performing big-data analysis. The processor is tasked with extracting data from massive sources and can end up sitting idle while it waits for previously-accessed data to be returned to it from memory. During this time, the processor has nothing to do and, with no alternative task available, just sits and waits, consuming power but yielding no results.
Shulaker explained: “If you try to run that in your computer [a big-data analysis task], you would spend over 96 percent of the time just being idle, doing absolutely nothing. You’re wasting an enormous amount of power.”
The new 3D chips overcome this issue by allowing the memory to be intertwined with the processor. Previous efforts to bake storage units onto silicon wafers have failed because the silicon has to be heated to over 1,000 degrees Celsius, a temperature which would melt media like hard drives or solid-state NAND cells.
The carbon nanotubes avoid this while continuing to retain properties similar to that of traditional silicon transistors. In a comparison test between a silicon transistor and an equivalent carbon nanotube one, the 3D chip would win “hands down”, according to Shulaker. It would be able to operate more quickly than the traditional silicon processor while consuming less power.
The team is now working to scale the technology and build it into a viable processor architecture for the future. A concept computer in 2013 proved the feasibility of the carbon nanotube processors but was slow and bulky as relatively few transistors were used.
A new system has made it possible to stack memory banks and transistors more precisely using miniscule wires and has resulted in carbon-based processors operating at 1,000 times faster than today’s silicon models. In practical use, the chips have already found placements as sensor wafers acting as detectors for infrared lighting and specific chemicals.
