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Replacing Copper With Pencil Graphite
Posted by
kdawson
on Tue Jul 24, 2007 06:27 PM
from the carbon-all-the-way-down dept.
from the carbon-all-the-way-down dept.
Late-Eight writes "A key discovery at Rensselaer Polytechnic Institute could help advance the role of graphene as a possible heir to copper and silicon in nanoelectronics. Researchers believe graphene's extremely efficient conductive properties can be exploited for use in nanoelectronics. Graphene, a one-atom-thick sheet of carbon, eluded scientists for years but was finally made in the laboratory in 2004 with the help of everyday, store-bought transparent tape. The current research, which shows a way to control the conductivity of graphene, is an important first step towards mass producing metallic graphene that could one day replace copper as the primary interconnect material on nearly all computer chips." Researchers are now hot to pursue graphene for this purpose over the previous favorite candidate, buckytubes (which are just rolled-up graphene). Farther down the road, semiconducting graphene might take over from silicon at the heart of logic chips.
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Keep Erasers Away (Score:5, Funny)
Re:Keep Erasers Away (Score:5, Funny)
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Re:Keep Erasers Away (Score:5, Funny)
I'll have to scan you-tube over the next few days for clips.
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http://www.myconfinedspace.com/wp-content/uploads
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Another Use For Graphic & Electricity (Score:2, Interesting)
There are even more advantages (Score:5, Interesting)
This will allow for much more efficient cooling of electronics, even more then Silicon on Diamond technology that is just starting to come out.
Re:There are even more advantages (Score:4, Informative)
To put this into perspective Steel is around 60 WMK, Silicon 149 WMK , Aluminum is 200 WKM, Copper is 400 WMK
And some nanotubes where reported as almost 10,000 WMK
Somehow I thought Silicon was more like 60wmk but is higher according to http://en.wikipedia.org/wiki/Silicon [wikipedia.org]
Parent
Re:There are even more advantages (Score:4, Informative)
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All we need now is a transistor made of soot and we can finally have the elusive all-carbon computer!
Way back when.... (Score:5, Interesting)
My 'solution' involved opening up the keyboard and retracing the mylar sheet connections with a pencil. It worked great -- but I needed to crack it open every few weeks and retrace it.
It's amazing what you can accomplish when you are fairly clever and poor.
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Engineering is the art of making what you want out of what you have.
The best engineering solutions come not from large budgets, but small ones.
Re:Way back when.... (Score:4, Informative)
Pushing the cpu up from 650 to 800mhz made *all* the difference...
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Re:Way back when.... (Score:5, Interesting)
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It's not as powerful as a modern Athlon 64 X2 3800+ (which is also 2x 2GHz, and I also own), and uses at least four times the power (and produces four times the heat), but I love it because I actually worked to build it instead of slapping together some parts.
Oh, an
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I don't know if these pens were readily available (though I bet they existed) when you had to repair your old Atari, but on
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I knew that, and I wasn't brilliant. I think I learned it from my old 200-in-1 kit manual, or early lessons in "how to use your ohmmeter." I remember being instructed to draw a line with pencil, and then connect the ends at different lengths across the line. It recommended striping the line multiple times, as well, and to check the difference.
I remember that! (Score:2)
I need to run out and buy some; chances are they won't exist anymore by the time I have kids.
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This might just work: (Score:2, Interesting)
More wishful thinking? (Score:2, Funny)
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I hope graphene is expensive... (Score:5, Funny)
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but (Score:5, Funny)
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Heh, now just combine this with nanobot and neural network technology and you'd have a self improving system, maybe even expanding at Moore's law's speed. You can increase the progress by breathing on it or doing sports in the vicinity. I wonder how many blows it will take until it becomes self-aware
I think they'd just need a chlorophyl machine to do that.
I find the idea of organic circuits interesting, but chlorophyl
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Also, by coincidence, your user number was chosen as a winner of a valuable prize in our no-fee lottery! Please remit payment of $5,000 to cover shipping and import duties to receive your prize valued in excess of $100,000.
Earlier Work? (Score:2)
pencils conduct electricity (Score:3, Interesting)
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I used to break pencils in two, sharpen a point and shave the wood off the opposite end of each half. Then I'd tape the halves down with the sharpened points nearly touching, and put crocodile clips on the exposed ends.
Carbon arcs are awesome for retina burns!
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I seem to remember having an electrical experiment kit that included an experiment that used a pencil lead as a variable resistor. This was back in the days when you had to carefully remove the "lead" from the wooden pencil, rather than use a convenient mechanical pencil lead. Anyone else remember doing this?
Pencil Trick (Score:2, Informative)
Cleverness will solve our problems (Score:2)
Huh? Getting Annoying (Score:2)
errrr.....
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Gimme a break- it's still a stupid ass title, and you are just being cranky. I'd say trying to be informative if you were not AC'ing.
Would make for one hell of a motor? (Score:2, Interesting)
They should talk to the chip bakers first.... (Score:4, Informative)
Getting from silicon to carbon. (Score:4, Interesting)
Yep. They need to cooperate with the silicon chip makers. And that's the really interesting bit...
Carbon can be a superresistor, a resistor, a semiconductor, or a conductor just by itself. The big, conjugated pi electron clouds you get above and below a graphite layer have lots of electrons in a single ground energy state, much like superconductivity. There are hopes that you can get some reduced dimension superconduction in carbon if you an up the electron density a bit. You may get this inside a buckytube where the curvature gives more electrons per unit volume.electron cloud is You could do this by rolling up a graphene into a buckytube. Then carbon could do the lot, electrically.
Fine. Carbon is clever stuff. However, we have spent a huge amount of time and effort on silicon. It is one small step on the periodic table, but one great leap for mankind. When we solder a device to a circuit board, there is a whole technology involved in getting from the submicron geometries and tiny singnals to the submillimeter sizes and microamp currents for things we can physically handle. We are going to need a new technology to go from the microscale of silicon to the nanoscale, quantum world of silicon. This could be thirty years of pouring research into new techniques before we ever get a useful device.
If, however, someone can come up with some way of using carbon on silicon, then we may be able to start working on practical carbon fabrication techniques and make them pay under much shorter timescales. I had always imagined the first application of carbon as some memory unit as memory usually involves banging out billions of copies of the same simple element, so the development costs in designing a single element are allowed to go higher than elsewhere. However, here is another option: we can deposit carbon onto an existing silicon surface - not as genuine epitaxy, but just using it as a flat surface, the way copper currently does. The next trick might be to get the film to roll itself into a buckytube. We have got the connections from silicon to carbon, and just the beginnings of practical self-assembly.
Whoo-hoo!
Parent
Bah, Physicists! They got it all wrong again. (Score:5, Informative)
Now, the packing of the orbitals is determined by the edges because of their constraints on orbital orientation. In the middle of the ribbon, you have a pure hex grid, and the orbitals, which can be visualized as taking half of each hex and painting a large C on it (these are not the same as the three bonding pi orbitals). Try it yourself: draw a hex grid and try to pack Cs. To visualize resonance, push on one end of a C and see how to repack the resulting structure. In the middle, you have three orientations at every node, but at the edges you don't. The more edges you have, the more constraints there are on the packing, and the more likely it is that the oribitals in the middle won't be in resonance with each other in a given direction. When you push on a C in such a grid, it will push other Cs sideways instead of along the ribbon, causing "resistance".
There are two types of edges, familiar to tile game developers as the vertical and horizontal orientation. In the horizontal packing, the flat side of each hex is bordering the edge, in the vertical the flat side is perpendicular to the edge. It turns out that if you have horizontal edges on your graphene ribbon, it is metallic; if you have vertical ones, it is semiconductive (which is another way of saying it has more resistance). If the edges are not quite straight, which will quite likely happen if you are making your ribbons via CVD or duct tape or something, you'll see a mix of both behaviors, resulting in a conductivity somewhere in between full-out and almost-nothing.
This is the trouble with modern physics - they just don't care about reality any more. If they only drew a few pictures, like real chemists do, they'd have seen this very easily. Instead they waste their time on simulations that only give them numbers they don't know how to interpret. Sheesh.
Graphene is a great story (Score:3, Informative)
The electrical engineers however, have said "meh." Graphene is a decent electrical conductor if you dope it with something - not as good as copper, but decent. It does have great thermal conductivity, though. The big problem with graphene is that you can't really make it in big sheets or long wires. The "tape" method is a great hack - simply stick the tape onto a chunk of graphite, then peel it off and stick it on a substrate (glass or silicon), then peel it off again. Odds are, now you have a sheet of graphene stuck to your substrate, somewhere. Bad news: the biggest piece you're likely to find will be 1-10 micrometers long, and you'll need an electron microscope to find it. This is great for investigating the electrical or thermal properties of graphene, but as for manufacturing, forget it.
As for graphene transistors, those are out too. Transistors should have a very high resistance when "off," and graphene doesn't. The maximum resistance a sheet of graphene can have is about 6 kiloOhms for a square sheet. Fundamentally, graphene is a semiconductor like silicon or germanium, but its band gap is zero, which basically means it can never be "off."
'Drano
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Of course, the reasoning isn't what the GP was saying. They actually do it do balance the conductivity with the weight of the wire since the cable needs both high conductivity and the ability to support itself without breaking or sagging too far.
Yes (Score:3, Informative)
"wouldn't quantum effects become a problem at that scale?"
Quantum effects create the properties those people are looking for.