Phase-Change Materials Could Boost Reconfigurable Chips

More powerful FPGAs and other reconfigurable chips could come from vertical wires made from phase-change material

3 min read

28 January 2008--A technology that would allow a computer chip to change the electrical resistance of some of its own wiring could lead to more-powerful reconfigurable microchips that can quickly adapt themselves to new tasks, researchers at IBM say.

Engineers at IBM’s T.J. Watson Research Center in Yorktown Heights, N.Y., produced a prototype device based on a type of material found in experimental memory chips. Normally, a ”via,” a hole leading from one layer of a chip’s wiring to another, is filled with a metal such as tungsten to provide an electrical connection between the layers. But in this case, the researchers used a phase-change material, a substance whose conductance can be switched between two states by briefly melting it. ”By changing the state of the phase-change material, you create an on-off switch,” says Kuan-Neng Chen, the research staff member who led the project.

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Two Startups Are Bringing Fiber to the Processor

Avicena’s blue microLEDs are the dark horse in a race with Ayar Labs’ laser-based system

5 min read
Diffuse blue light shines from a patterned surface through a ring. A blue cable leads away from it.

Avicena’s microLED chiplets could one day link all the CPUs in a computer cluster together.


If a CPU in Seoul sends a byte of data to a processor in Prague, the information covers most of the distance as light, zipping along with no resistance. But put both those processors on the same motherboard, and they’ll need to communicate over energy-sapping copper, which slow the communication speeds possible within computers. Two Silicon Valley startups, Avicena and Ayar Labs, are doing something about that longstanding limit. If they succeed in their attempts to finally bring optical fiber all the way to the processor, it might not just accelerate computing—it might also remake it.

Both companies are developing fiber-connected chiplets, small chips meant to share a high-bandwidth connection with CPUs and other data-hungry silicon in a shared package. They are each ramping up production in 2023, though it may be a couple of years before we see a computer on the market with either product.

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