
Nanoscale Vacuum-Channel Transistor - dhotson
https://en.wikipedia.org/wiki/Nanoscale_vacuum-channel_transistor
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hilbert42
I can recall seeing something like this in a magazine decades ago but my
recollections are vague—although if I saw the photo of the device that
accompanied the article then I'd reckon I'd still recognize it.

Essentially, it was a miniature filament-less vacuum tube with I think a
silicon emitter/cathode that looked somewhat volcano shaped, the top of which
electrons were emitted by electric field emission rather than the more usual
thermionic emission.

I cannot now vouch for the size of it but a tiny nuvistor,
[https://en.wikipedia.org/wiki/Nuvistor](https://en.wikipedia.org/wiki/Nuvistor),
along side of it would have been a giant by comparison.

I'd be interested if anyone has a better recollection than me and if this is
essentially the same device as mentioned in the article.

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mannykannot
In this recent article [1], about half way through, the author writes about
work on cold cathodes. These are field-emission devices like you describe.

Vacuum-channel transistors do not actually use a vacuum, because the channel
is much shorter than the mean free path of electrons in air, and they usually
cross the channel without colliding with any air molecules, and, despite the
field strength, without gaining sufficient energy to ionize them when they do.

[1] [https://spectrum.ieee.org/semiconductors/devices/the-
quest-f...](https://spectrum.ieee.org/semiconductors/devices/the-quest-for-
the-ultimate-vacuum-tube)

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hilbert42
Thanks for that. It's coming back. I now remember I've seen that article but I
wasn't thinking of it when I wrote but another one on the same or similar
matter. Seems I've concatenated both together in my mind even though they were
written decades apart.

That said, the original articles seemed conceptually important to me at the
time so at least some of the info stuck. It'll be interesting to see if the
technology eventually makes into mainstream. I'd put money on it that it will.

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dcminter
Ha, this reminds me of Pratchett's _other_ discworld...

"Kin had seen things like it in a museum. It was a valve, a sort of neolithic
integrated circuit. Only this was a valve such as might be built by someone
who had never developed the transistor, so that more and more ingenuity had
been devoted to perfecting the existing technology." \-- Strata, Terry
Pratchett.

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peter_d_sherman
I always love reading about weird/esoteric transistors... <g>

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mirimir
Wow. Nanoscale vacuum tubes.

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gigatexal
Bring new weight to the saying: “Everything that is old is new again”

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mirimir
It reminds me of the nanomachines in vacuum bubbles featured in Stephenson's
_The Diamond Age_. And maybe earlier in Bruce Sterling's work.

