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Scientists Create First Functional Molecular Transistor
Dananajaya Ramanayake sends along this excerpt from Wired:
"Nearly 62 years after researchers at Bell Labs demonstrated the first functional transistor, scientists say they have made another major breakthrough. Researchers showed the first functional transistor made from a single molecule. The transistor, which has a benzene molecule attached to gold contacts, could behave just like a silicon transistor. The molecule's different energy states can be manipulated by varying the voltage applied to it through the contacts. And by manipulating the energy states, researchers were able to control the current passing through it."
Now when they say "those games are killing your social life" it can be held as literal as well as figurative.
or two, if the price is right. ;~) However, right now, it smells like vaporware.
And I have the same question for the memristor. Both look very interesting to me.
So what happens when the Benzene evaporates away? Does it take your bits with it?
How stable is it? This would drastically lower the costs of production and effectively approach the size limit of a transistor, but for something that they purport to use in supercomputing applications, they'll have to find a way to make it last a long time. That's the hurdle that's preventing most organic devices (LEDs, PVs, TFTs).
Long way to go here.
I have left slashdot and am now on Soylent News. FUCK YOU DICE.
This would make a feature size of about 0.3nm?
Rod Taylor
Seems quite interesting but:
1) Organic molecules can be quite large so it could not necessarily be a better option to current manufacturing processes.
2) The original linked article states that "The possibility of using organic components with enzyme stimulated responses has some interesting possiblities" and I am wondering how much is reality and how much is possibility.
"The transistor, which has a benzene molecule attached to gold contacts, could behave just like a silicon transistor." It isn't clear how large the transistor as a whole is. A benzene molecule is pretty small with only 12 atoms. That presumably isn't the entire transistor. Whether they mean benzene attached to something else isn't clear from the article. However, given that prior small transistors are on the order of 10s of atoms thick at minimum, this seems like a major improvement. It looks like Moore's law will live for a bit longer yet.
See also Observation of molecular orbital gating.
-kgj
1) Current manufacturing process are struggling to get transistors any smaller than millions of molecules each, and Benzine, the molecule specifically used here, is not very big.
2) Any manufactured product using this discovery is yet to be invented. Such a product is still a decade or two away. In other words, nothing other than the existance of a molecular transister is a reality, and everything else is a possibility. Duh. "Interesting Possibilities" drive science, it's mostly what these guys look for. They leave actually producing things with their discoveries to engineers.
Security is mostly a superstition... Avoiding danger is no safer in the long run than outright exposure. - Helen Keller
What are they going to call this thing? Not the "atom"!
Seems remarkably similar to what other researchers have already done:
03 Dec 2009
"Researchers from Helsinki University of Technology (Finland), University of New South Wales (Australia), and University of Melbourne (Australia) have succeeded in building a working transistor, whose active region composes only of a single phosphorus atom in silicon. The results have just been published in Nano Letters."
http://www.tkk.fi/en/current_affairs/news/view/yhden_atomin_transistori_loydetty/
For anyone interested in the actual paper, it's H. Song, et al., Nature 462 p. 1039-1043
As a (biased) researcher in the field, my opinion of this is that it is no more than an attention grab and will do little to advance science (this is pretty typical of Nature papers, though):
1. The contacts are still very large compared to the channel (what they call the "transistor"). Without advances in scaling down contacts, you won't see a meaningful decrease in transistor density from this technology. What's more, they don't include an actual picture of the device, so there's no way to tell how big the contacts actually are.
2. Like most researchers, they "cheat" and use a very large (probably macroscopic) back gate to modulate current. The idea of a field effect transistor is that you apply a voltage perpendicular to the direction of current, which causes charges to move along the electric field and either hinder or help transistor current by creating (or eliminating) a potential well in the transistor. In real devices, you have billions of these transistors on a single wafer and so at some point you have to actually place a local gate, which usually has a huge negative effect on transistor operation.
3. They don't appear to have any good way of controlling how many of their transistors work (they rely on chance to get these molecules to bridge the gap between electrodes)
While certainly thought-provoking, as an engineer I am not particularly impressed until I see them using scalable methods.
Looks interesting but behind pay wall.
Any related free links?
Physics is like sex: sure, it may give some practical results, but that's not why we do it.
I wouldn't want to spoil your joy, but there it is.
[abstract]
We have developed nanoscale double-gated field-effect-transistors for the study of electron states and transport properties of single deliberately implanted phosphorus donors. The devices provide a high-level of control of key parameters required for potential applications in nanoelectronics. For the donors, we resolve transitions corresponding to two charge states successively occupied by spin down and spin up electrons. The charging energies and the Land g-factors are consistent with expectations for donors in gated nanostructures.
The whole Article at Nano letters
hard soft is like on off right?
pdf: http://bit.ly/8yzijS
la la la filter buster text goes here
I performed very similar research in a lab. The technique used is called a mechanically controllable break junction (MCBJ). Basically you make a very thin gold bridge using fairly standard e-beam nanofabrication procedures on a flexible substrate. You then bend the substrate and can thin the gold bridge down to a single atom in one-atom steps, then to a tunnel gap. You can then put this gap in a liquid (benzene or some other) and trap molecules in it. I actually did an undergrad thesis on conduction through a single gold atom and yes, while my device was technically 1 atom large, the entire apparatus was fist-sized. The bendy substrate on which everything was fabricated was about 1" by 0.25" in size. All this for a single atom. Now you can be a bit smarter and do it as a large array on a substrate this size, but still, this is about the size these guys are working with too. The main benefit of this is that they are testing the physics and properties required to make a molecular transistor. Scaling up to producing billions of these in a usable array is a completely separate problem.
1) Current manufacturing process are struggling to get transistors any smaller than millions of molecules each, and Benzine, the molecule specifically used here, is not very big.
The current state of the art manufacturing process is at 32nm, which is much less than millions of molecules each. 32nm is 320 angstrom, so we're at roughly 300 molecules size.
"1) Current manufacturing process are struggling to get transistors any smaller than millions of molecules each"
What fucked up math are you using? In fact, where are you pulling those numbers from? Sources?
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
I assume once they add the Acetone and Turpentine, we'll end up with a DIP package?
This must be the 5th article I've seen in the past 2 years claiming scientists invented the first ever single-molecule transistor. Only a few months ago it was a phosphorous atom on silicon. Now it's benzene. Why do they keep saying it's the first?
Burnt toast might have a use now...
At this level, the only manufacturing process that could work would be chemical, not lithography like regular chip manufacturing.
So, until you have chemists who know how to place a billion+ molecules in exactly the right formation to make a device turing-complete, you won't see this in any application. Also, how much heat does this molecule generate at various energy states? I mean, if liquid nitrogen cooling isn't commercially viable for home computers, how feasible is a multi laser-cooled device?
Still, it is a record--the smallest transistor I've heard of before this was about 15 molecules across. Pretty cool.
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Nanotech Feed @ Feed Distiller
"functional transistor? thanks but no thanks! wake me up when they discover an object-oriented one"!!!