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Now that 3D Chips Are Here, What Does the Next Generation Hold?

Dutch researchers are developing new methods for fabricating 3D nanostructures in silicon

2 min read
Now that 3D Chips Are Here, What Does the Next Generation Hold?

Now that Intel will definitely be introducing its 22-nm Tri-Gate transistor—referred to as a 3-D chip due its 3-D ridge (or fin, thus the alternative name, FinFET) in which electrons runs through—it seems the era of 3-D chips are here sooner than expected. (Read and watch this interesting interview with Intel Senior Fellow Mark Bohr on how we got to this point.)

With this as its context, Dutch researchers from MESA+ Institute at the University of Twente, University of Eindhoven, ASML company and TNO Institute have developed processes by which they can rapidly fabricate “large 3-D photonic in mono-crystalline silicon using CMOS compatible processes”  that should enable novel fabrication methods for computer chips.

The researchers have published their work in a series of three papers and in the one published by the Journal of Vacuum Science and Technology have been able to fabricate a 3-D nanostructure in silicon by making etch marks on two sides of s wafer.

"There are many advantages of our fabrication route" says Willem Tjerkstra, a researcher at the MESA+ Institute in an interview with Nanowerk. "A complex 3-D structure can be made in only two etching steps, instead of tediously making such a structure by stacking layer-by-layer, as in standard CMOS-compatible fabrication. In our paper, we propose that our method allows the realization of 3-D computer chips that have more functional units concentrated on the same area. We also predict the realization of chips on different sides of liquid channels for microfluidic, or for cooling purposes."

In the two succeeding papers, the researchers described a “3D etch-masking method to realize a complex 3-D periodic array (a crystal structure) of pores in silicon” and then in the third paper observed for the first time the long-predicted phenomenon of the spontaneous emission of light from quantum dots in a 3-D photonic band gap.

It will be interesting to see if techniques such as these find their way into the next generation of 3-D chips when dimensions go down to 14nm and then 10nm.

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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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