From joelnic–(at)–iva.EECS.Berkeley.EDU Thu Aug 31 22:02:38 CDT 1995
Article: 666 of rec.audio.tubes
Path: geraldo.cc.utexas.edu!cs.utexas.edu!swrinde!howland.reston.ans.net!agate!joelnice
From: joelnic–(at)–iva.EECS.Berkeley.EDU (Joel Nice)
Newsgroups: rec.audio.tubes
Subject: Tomorrow’s tubes?
Date: 31 Aug 1995 00:24:00 GMT
Organization: University of California, Berkeley
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In article <42164p$ck--(at)--ontainebleau.ensmp.fr> you write:
>May be they use a network of silicon vacuum microtriods. Microtriod
>is a cold cathod vacuum silicon device the dimension of which
>is around one hundred of micrometer (snip). Microtriod was designed
>few years ago for microelectronics and thought to >be the faster and
>the more linear amplifying device.
At the Berkeley Sensor & Actuator Center where I work, researchers
created microvacuum tubes on a silicon chip. For details please
read: K. R. Williams and R. S. Muller, “IC-Processed Hot-Filament
Vacuum Microdevices,” 1992 IEEE International Electron Devices Meeting
(IEDM ’92), pp. 387-390, San Francisco Hilton, San Francisco, CA,
December 13-16, 1992.
Here is a quote:
>”Micromachined vacuum devices that employ a hot tungsten filament as a
>source of electromagnetic radiation and thermionically emitted electrons
>have been fabricated. These hot-filament devices have been
>characterized for use as “microlamps”, vacuum diodes, and triodes.
>Coplanar filaments are used for the grids in the triodes. The filaments
>are typically 200-um long and are suspended over a cavity in the silicon
>substrate. The devices tested were operated in a pumped vacuum chamber…
>in this research, we employ thermionic emission from heated tungsten
>filaments as the source of electrons in devices we call “microtubes.”
I was trying to convince one of the researchers that plays gtr to
hook up some of these microtubes to some of our microresonator filters
and we have micro piezo element speakers and microphones as well to
creat the world’s first microtube instrument amplifier on a computer
chip. Of course, this would all be on the micron size level. So,
you could create quite a sizeable “stack” on one 4 in. wafer. Just
thought that some readers would find this interesting.
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From lecleac–(at)–gi.ensmp.fr Thu Aug 31 22:02:55 CDT 1995
Article: 689 of rec.audio.tubes
Path: geraldo.cc.utexas.edu!cs.utexas.edu!swrinde!howland.reston.ans.net!tank.news.pipex.net!pipex!oleane!univ-lyon1.fr!news-rocq.inria.fr!news-sop.inria.fr!cemef.cma.fr!news
From: lecleac–(at)–gi.ensmp.fr (Le Cleac’h Jean-Michel)
Newsgroups: rec.audio.tubes
Subject: Re: Tomorrow’s tubes?
Date: 31 Aug 1995 12:03:56 GMT
Organization: Centre Geologie Ingenieur
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References: <422vf0$l9--(at)--gate.berkeley.edu>
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In article <422vf0$l9--(at)--gate.berkeley.edu>,
joelnic–(at)–iva.EECS.Berkeley.EDU says…
>
>
>In article <42164p$ck--(at)--ontainebleau.ensmp.fr> you write:
>>May be they use a network of silicon vacuum microtriods.
>At the Berkeley Sensor & Actuator Center where I work, researchers
>created microvacuum tubes on a silicon chip. For details please
>read: K. R. Williams and R. S. Muller, “IC-Processed Hot-Filament
>Vacuum Microdevices,” 1992 IEEE International Electron Devices Meeting
>(IEDM ’92), pp. 387-390, San Francisco Hilton, San Francisco, CA,
>December 13-16, 1992.
>
>Here is a quote:
>>”Micromachined vacuum devices that employ a hot tungsten filament as a
>>source of electromagnetic radiation and thermionically emitted
electrons
>>have been fabricated. These hot-filament devices have been
>>characterized for use as “microlamps”, vacuum diodes, and triodes.
Joel,
Thank you for the information about those microtube with a hot cathod.
I found, in my archives a previous answer of mine about the subject of
cold cathod microtriodes.
You’ll find here some interesting papers in english.
Here was my post:
Microtriods:
If you are interested on the subject, please check those references:
“A come back for the vacuum tube” by Lawrence M. Fisher
New York Times 18 May 1988.
There are few conferences on that topic intitled “VACUUM MICROELECTRONIC”
with the subtitle “BACK TO THE FUTURE “:
The first one was in Williamsburg, Virginia, USA, 13-15 June 1988 and
organised by Henry Gray of the Naval Research Center in washington and by
Charles Spindt of the Stanford Research Institute.
The second one was held in Bath ,Great Britain, 24-26 July 1989.
As you can imagine those were not conferences for “audiotubegurus”. One
major conclusion was: “microtriods will be probably in the future the
fastest electronic components”.
Interesting papers in french can be found in:
“L’Audiophile” N
