
Making Radio Chips for Hell - rbanffy
https://spectrum.ieee.org/tech-talk/semiconductors/devices/making-radio-chips-for-hell
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dxf
These chips are not really for Hell, as Hell is much hotter than 500°C, see
Healey, T (1979). A Refutation of the Proof That Heaven is Hotter Than Hell.
The Journal of Irreproducible Results, 25(4), 17-18

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shakna
Well that felt like a tease. They're using silicon carbide and... That's all
the detail she wrote.

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BostonEnginerd
SiC and GaN are being used for a fair number of parts these days for RF
applications. It seems that the novel part of this paper is that the device
worked up to 500C. The device worked for 3 hours with some degradation, likely
due to Al electromigration from the metallization.

The acutal paper is here:
[https://ieeexplore.ieee.org/document/8345290/](https://ieeexplore.ieee.org/document/8345290/)

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darkmighty
I wonder if simply cooling isn't an option in those applications? I guess
that'd depend on the chips power output. Otherwise you could just surround it
in a really good insulator and pump residual heat out somehow (maybe can
peltiers withstand such high temps using multiple stages?)

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BostonEnginerd
Cooling only works if you have somewhere to put the extra energy. Peltiers are
inefficient to run and generate a ton extra heat. It's best to build something
that can run with as little support needed.

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darkmighty
Indeed, cooling would be quite bulky and require lots of extra energy. But for
an environment like Venus cited (instead of small sensors), I think it should
be a good option. The Carnot efficiency to cool from a Venutian environment
(462C) down to 50C (reasonable chip temp) is a surprisingly good ~60%. In
practice you might get 15% (? plus insulation leaking), that should still
allow cooling a chip of less than ~1 watt of tdp without too much hassle
inside a robot.

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cushychicken
Very neat. Dealing with a thermal problem in a design right now at work; wish
these were available for an 802.11 radio!

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namibj
The issue is that your 802.11 radio needs digital logic, whereas this is just
a dumb mixer. Which is, conceptually, just a dual-gate MOSFET run with a bias
voltage to exhibit linearity and often without the body diode, in order to
permit AC inputs. I do hope for SiC based VLSI, but this won't happen any time
soon. One could probably run them pretty hot though, possibly without special
cooling fans or such, or at temperatures that allow radiating the generated
heat away into space, as long as it's not needed/used for anything better.
This would also allow the recycling of waste heat from electronics for
industrial processes and generating steam, for which we already know pretty
well how to pipe it across a city in a city-scale central heating system.

Absorption cooling (often using ammonia/water as a mixture) could be powered
by this and provide sufficiently low temperatures for airflow-free cooling of
e.g. hard discs or other components where the temperature would kill them.

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dzdt
I think the VLSI is coming sooner than you expect! There are already teams
trying to build a 4 bit microprocessor. And when they get the layering and
packaging working, scaling is going to go a LOT faster than Moore's law did
because so much of the technology from silicon will just be reusable.

[1]
[http://www.imapsource.org/doi/abs/10.4071/2016-HITEC-242?cod...](http://www.imapsource.org/doi/abs/10.4071/2016-HITEC-242?code=imap-
site)

[2]
[https://www.lpi.usra.edu/vexag/meetings/archive/vexag_14/pre...](https://www.lpi.usra.edu/vexag/meetings/archive/vexag_14/presentations/21-Zetterling%20-SiC-
Electronics.pdf)

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namibj
Thanks. Any predictions? How long until we get a 486 in SiC?

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therealjumbo
OT, but the site doesn't load in firefox for me.

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conover
Hmmm. Fine in Firefox (59.0.2) for me.

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l0b0
$ cat reduce-clickbaitiness.sed

s/Hell/Venus/

And it's portable to every major news outlet.

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vertexFarm
I think it's a concise and appropriate title. Making electronics that will
work on Venus is essentially designing for hell, with all the heat, pressure,
corrosives, and who knows what else. And 14,000 Gs of acceleration? Wow. I've
never heard of that happening in hell.

This one weird trick lets a microchip survive temperatures of 500C! Intel and
heat sink manufacturers HATE this! That would be clickbait.

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mr_toad
I would have been more interested if the title had said Venus.

