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Tunnelling electrons speed up large area carbon electronics
Physorg.com | University of Surrey | Advanced Technology Institute ^ | December 26, 2005

Posted on 12/26/2005 11:49:22 AM PST by sourcery

Researchers at the Advanced Technology Institute at the University of Surrey have reported in the January 2006 issue of Nature Materials the first demonstration of negative resistance in amorphous semiconductors.

Electronics based on amorphous materials is the key to large area low cost driver circuitry in flat panel displays, but their operating speed has been limited by the difficulty with which electrons move through disordered amorphous materials. Now, the observation of negative resistance offers the prospect of low-cost devices switching at Gigahertz rates, and opening up applications from large area display drivers to high-speed electronics for mobile communications. These devices are suitable to be used in combination with plastic electronics due to the room temperature deposition process.

The breakthrough at Surrey has been to make devices with layers only a few nanometres thick, through which electrons can pass by quantum-mechanical tunnelling. In a three-layer structure, the composition and thickness of the layers control the energies at which electrons are allowed to tunnel, and can give rise to a region of negative resistance. Such ‘resonant tunnelling diodes’ have been extensively studied in highly ordered crystalline semiconductors such as gallium arsenide, and account for some of the highest-speed electronic devices ever demonstrated. However, previous attempts to realise negative resistance in amorphous materials (e.g. amorphous silicon) have proved unsuccessful.

"This work extends the potential of amorphous carbon electronics to high speed switching at GHz rates, and follows our earlier demonstration of room temperature processing of carbon electronics on plastic" said the lead investigator of the team, Professor Ravi Silva. "Such ground breaking work was only possible due to the flexible funding afforded by the 5-year Portfolio Partnership between the University of Surrey and the Engineering and Physical Sciences Research Council (EPSRC)".

The Surrey devices are made from thin layers of diamond-like carbon, a material which has the added advantage of chemical robustness, thermal stability, high resistance to electrical breakdown, and biocompatibility. It can be deposited over large areas at room temperature, which makes it compatible with low-cost, flexible plastic substrates. The newly demonstrated suitability of diamond-like carbon for quantum electronics may give rise to the establishment of a new family of high speed carbon based high power devices such as tunnel transistors, oscillators and hybrid devices. These devices would offer the possibility of high speed nano-electronics circuits, stable against chemical attack and suitable for high temperature operation, compatible with large area low cost production.

The work was sponsored by the Portfolio Partnership and Carbon Based Electronics Programmes of the Engineering and Physical Sciences Research Council (EPSRC) in the UK.


TOPICS: Miscellaneous; News/Current Events; Technical; United Kingdom
KEYWORDS: physics; science

1 posted on 12/26/2005 11:49:23 AM PST by sourcery
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To: AntiGuv; bobbyd; DoughtyOne; Ernest_at_the_Beach; FairOpinion; phatoldphart; RightOnTheLeftCoast; ..

Ping


2 posted on 12/26/2005 11:50:09 AM PST by sourcery (Either the Constitution trumps stare decisis, or else the Constitution is a dead letter.)
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To: sourcery

This should help bring down the price of plasma screen TVs a bit ...


3 posted on 12/26/2005 11:57:17 AM PST by Ken522
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To: fnord; phantomworker; sd-joe; Jack Black; TXBSAFH; SouthernBoyupNorth; Ichneumon; ...

Geezer Geek ping.

This is a very low-volume ping list (typically days to weeks between pings).
FReepmail sionnsar if you want on or off this list.

4 posted on 12/26/2005 12:21:43 PM PST by sionnsar (†trad-anglican.faithweb.com† || Libs: Celebrate MY diversity, eh! || Iran Azadi 2006)
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To: sourcery
" thermal stability, high resistance to electrical breakdown " ......
Imagine that, having electronic circuits and CPUs that won't frie no matter how much you over load the circuit or try to frie the circuits.
But, I am sure the electronic consumer product companies will find a way to make the product fail or fall apart or go up some how were you have to buy a new one every 3 to 4 years.
5 posted on 12/26/2005 12:55:13 PM PST by Prophet in the wilderness (PSALM 53 : 1 The FOOL hath said in his heart , There is no GOD .)
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To: sourcery

Now this is cool. I see money to be made here.


6 posted on 12/26/2005 2:23:31 PM PST by Dawggie
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To: Prophet in the wilderness

The eccofreaks have done that for you. By treaty lead alloy solder is banned from consumer electronics. Our high tech goodies are put together with tin solder (formerly tin lead alloy). Tin solder is unstable. Our toys will start falling appart in 10 years.


7 posted on 12/26/2005 2:32:28 PM PST by Dawggie
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To: Dawggie
Well,, they could find someway to make Gold solder, but that would be very expensive
8 posted on 12/26/2005 4:06:02 PM PST by Prophet in the wilderness (PSALM 53 : 1 The FOOL hath said in his heart , There is no GOD .)
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To: sourcery

Negative resistance? The obvious use for this technology is promiscuous, anatomically correct female androids!


9 posted on 12/26/2005 5:59:51 PM PST by SunkenCiv ("In silence, and at night, the Conscience feels that life should soar to nobler ends than Power.")
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To: SunkenCiv
Negative resistance? The obvious use for this technology is promiscuous, anatomically correct female androids!

I dunno, "Resistance is useless" didn't help the Vogon.

OTOH, look at Seven of Nine...

...and Harcourt Fenton Mudd.

Cheers!

...and Merry Christmas!

10 posted on 12/26/2005 7:32:54 PM PST by grey_whiskers (The opinions are solely those of the author and are subject to change without notice.)
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To: grey_whiskers

:')


11 posted on 12/26/2005 7:37:48 PM PST by SunkenCiv ("In silence, and at night, the Conscience feels that life should soar to nobler ends than Power.")
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