Jumping the gap may make electronics faster

Jumping the gap may make electronics faster
A section of a circuit board showing microcircuits. Credit: antoinebercovici

A quasi-particle that travels along the interface of a metal and dielectric material may be the solution to problems caused by shrinking electronic components, according to an international team of engineers.

"Microelectronic chips are ubiquitous today," said Akhlesh Lakhtakia, Evan Pugh University Professor and Charles Godfrey Binder Professor of Engineering Science and Mechanics, Penn State. "Delay time for signal propagation in metal-wire interconnects, electrical loss in metals leading to temperature rise, and cross-talk between neighboring interconnects arising from miniaturization and densification limits the speed of these chips."

These are in our smartphones, tablets, computers and and they are used in hospital equipment, defense installations and our transportation infrastructure.

Researchers have explored a variety of ways to solve the problem of connecting various miniaturized components in a world of ever shrinking circuits. While photonics, the use of light to transport information, is attractive because of its speed, this approach is problematic because the waveguides for light are bigger than current microelectronic circuits, which makes connections difficult.

A pulse-modulated SPP wave moving right, guided by the interface of a dielectric material (above) and a metal (below), suddenly encounters the replacement of the dielectric material by air. Most of the energy is transmitted to the air/metal interface but some is reflected to the dielectric/metal interface. The video spans 120 femtoseconds.

The researchers report in a recent issue of Scientific Reports that "The signal can travel long distances without significant loss of fidelity," and that "signals can possibly be transferred by SPP waves over several tens of micrometers (of air) in microelectronic chips."

They also note that calculations indicate that SPP waves can transfer information around a concave corner—a situation, along with air gaps, that is common in microcircuitry.

A pulse-modulated SPP wave moving right, guided by the interface of a dielectric material (above) and a metal (below), suddenly encounters the replacement of the dielectric material by air. Most of the energy is transmitted to the air/metal interface but some is reflected to the dielectric/metal interface. The video spans 120 femtoseconds. Credit: Akhlesh Lakhtakia, Penn State

SPPs are a group phenomenon. These quasi-particles travel along the interface of a conducting metal and a dielectric—a non-conducting material that can support an —and on a macroscopic level, appear as a wave.

According to Lakhtakia, SPPs are what give gold its particular shimmery shine. A surface effect, under certain conditions electrons in the metal and polarized charges in the can act together and form an SPP wave. This wave, guided by the interface of the two materials can continue propagating even if the metal wire has a break or the interface terminates abruptly. The SPP wave can travel in air for a few 10s of micrometers or the equivalent of 600 transistors laid end to end in a 14 nanometer technology chips.

SPP waves also only travel when in close proximity to the , so they do not produce crosstalk.

The problem with using SPP waves in designing circuits is that while researchers know experimentally that they exist, the theoretical underpinnings of the phenomenon were less defined. The Maxwell equations that govern SPP waves cover continuum of frequencies and are complicated.

"Instead of solving the Maxwell equations frequency by frequency, which is impractical and prone to debilitating computational errors, we took multiple snapshots of the electromagnetic fields," said Lakhtakia.

These snapshots, strung together, become a movie that shows the propagation of the pulse-modulated SPP wave.

"We are studying tough problems," said Lakhtakia. "We are studying problems that were unsolvable 10 years ago. Improved computational components changed our way of thinking about these problems, but we still need more memory."


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More information: Rajan Agrahari et al, Information Transfer by Near-Infrared Surface-Plasmon-Polariton Waves on Silver/Silicon Interfaces, Scientific Reports (2019). DOI: 10.1038/s41598-019-48575-6
Journal information: Scientific Reports

Citation: Jumping the gap may make electronics faster (2019, September 27) retrieved 15 October 2019 from https://phys.org/news/2019-09-gap-electronics-faster.html
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User comments

Sep 27, 2019
The writer needs to define what SPP stands for.
Best guess is Surface Plasmon Polariton, but that is only a guess.

Sep 27, 2019
The writer needs to define what SPP stands for.
Best guess is Surface Plasmon Polariton, but that is only a guess.


Thank you. I came here to say the same thing.
https://en.wikipe...olariton

Sep 27, 2019
@etudiant
@checksinthemail
The writer needs to define what SPP stands for... a guess.
it's a logical guess considering the following:
from the study
As surface-plasmon-polariton (SPP) waves are localized, signal delay and crosstalk may be reduced by the use of optical interconnections based on SPP waves...
from the article
SPPs are a group phenomenon. These quasi-particles travel along the interface of a conducting metal and a dielectric—a non-conducting material that can support an electromagnetic field—and on a macroscopic level, appear as a wave
from wiki
Surface plasmon polaritons (SPPs) are electromagnetic waves that travel along a metal–dielectric or metal–air interface, practically in the infrared or visible-frequency...
They are a type of surface wave, guided along the interface in much the same way that light can be guided by an optical fiber.

Sep 27, 2019
They also note that calculations indicate that SPP waves can transfer information around a concave corner—a situation, along with air gaps, that is common in microcircuitry.

My information corner is convex, however, preventing comprehension transfer...

Sep 27, 2019
does this relate to Moore's Law? if anyone can explain

Sep 28, 2019
does this relate to Moore's Law? if anyone can explain
If I understood correctly (the article is kind of vague) this is research about a potential fundamentally different computing paradigm; without silicon, and without even transistors. If we define Moore's Law strictly this research does not relate to it, because Moore's Law is all about transistors and the rate of their doubling. If we define Moore's Law more broadly and loosely then it does, since this research might (just might) some day result in faster and/or more energy efficicient computers.

Sep 28, 2019
So, is the future of microelectronics, synapses?

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