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Replacing Copper With Pencil Graphite
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.
This will work just fine until someone decides to clean the conductors at their card's edge with an eraser.
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
Buckytubes (which are just rolled-up graphene) are also known as Nanotubes, have conductivities of almost 1000 WKM (watts per meter kelvin) Graphene sheets should also have similar conductivities. I expect it would also be quite strong under tension.
This will allow for much more efficient cooling of electronics, even more then Silicon on Diamond technology that is just starting to come out.
I am always doing that which I can not do, in order that I may learn how to do it. - Pablo Picasso
I had an atari 800 xl years ago (circa 1980s). A friend had spilled milk on the keyboard and a number of keys stopped responding.
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.
Seeing as buckytubes have enormous conductivity, and are strong under tension, graphene should act similar, providing a far better replacement for silicon and copper. I do not think that the transition will come soon, but this is a great innovation and ahead of its time. I personally think that buckytubes should be looked into in greater detail before attempting graphene.
I doubt I'd do anything more than pencil this in for somewhere 5 years... no make that 7 years... no, we've really almost perfected it this time...
I am not an expert. If I am misled in something, please correct me.
I sort of like seeing the once-a-week news story about how some meth-head electrocuted himself in the process of stealing copper wire to sell for scrap. I'd hate to see the demand for copper go down!
Thanks to the War on Drugs, it's easier to buy meth than it is to buy cold medicine!
So light intensity is measured in candles, will a universal metric for measuring processing power be named 'pencils'?
Skiffy is Spiffy, but Ort is tort.
is it carbon neutral?
Cool! Amazing Toys.
After recent rash of copper and metal thief, I hope this will cut down on cooper and metal thieves... if Darwin doesn't win first:
= 44907r .html?ex=1185336000&en=a76b664a9720e53d&ei=5055&pa rtner=RRCOLUMBUS7 2,152949,00.html
http://www.wbir.com/news/local/story.aspx?storyid
http://www.nytimes.com/2007/07/17/us/17brfs-coppe
http://www.wyff4.com/news/9484796/detail.html
http://www.sabcnews.com/south_africa/general/0,21
A group at Columbia (some people from Phil Kim's group, I think) published something along these lines in Physical Review Letters back in... May? I don't have access to my copies at the moment, so I don't know for sure. I believe that their paper references an even earlier paper (January?) on arxiv by a group from Thomas Watson. I haven't read the IBM paper, but I remember the Columbia paper being interesting.
I used to have one of those 200-in-1 electronics kits when I was about 12. You know the deal, comes with a couple integrated circuits and mostly resisters and some capacitors, usually an AM tuner. Anyway, I found that if you hook its bank of six AA batteries up to two wires and touch the two wires to the lead core of a wooden pencil for only a couple seconds, it heats the lead core of the wooden pencil up so that it is too hot to touch.
When I was younger I used to have fun with a variable transformer that originally was used for a model train set. It had a wiper-type slider that would go from 0 to 12(?) volts from left to right. I discovered by placing the contacts across the graphite in a pencil I could heat the graphite until it glowed cherry red and caused the wood of the pencil to start smoking. Good times.
A squid eating dough in a polyethylene bag is fast and bulbous, got me?
Why is it "pencil graphite"? Why not just graphite? Is it because we're all too stupid to know that graphite is used in pencils? Or is there something magical about the graphite found in pencils that makes it particularly useful for making chips? I guarantee that there are no pencils filled with graphene.
A common method for unlocking old Athlon and Duron processors was using a good old pencil to connect the bridges. They're catching on!
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Imagine a huge coal burning power plant spewing carbon which is then sucked into a chimney next door at the semiconductor processing plant.
is it just me or does it make more sense to emphasize reasearch in perfecting more traditional technology, like copper? IBM has already proved that copper is a viable alternative to aluminium in chips back in the late 90's, and as expensive as copper is, I'm betting it's a hell of a lot less expensive than chains of individual carbon atoms.
In my high school electronics classes we discovered that you can set a pencil on fire by connecting the graphite to a variable power supply. It'll spark a lot too, which made it that much more enjoyable. Lead from mechanical pencils worked even better, which resulted in a lot of burn holes in desks and our books.
If I'm not mistaken the term is "popping a socket". Pull the "lead" out of the pencil, put two pieces into the socket (one in each side) the wrap tissue around another piece with the graphite sticking out both ends. Touch that piece to the two in the outlet and you now have a piece of tissue on fire to light something else with.
Where did graphite pencils get mentioned in the article (yup, I even read it). Even Wiki has nothing relating graphene to pencils. /. is turning into a rag with sensationalistic headlines that have nothing to do with the article and often even the summary. The sad part is that the stuff might even be interesting without the "Rabbit Fur wrapped Cat5 outperforms fibre".
errrr.....
Vote monkeys into Congress. They are cheaper and more trustworthy.
Sir, Graphite is used in pencils, Graphene is just sheet of Graphite.
"Graphenes are the 2-D counterparts of 3-D graphite." http://en.wikipedia.org/wiki/Graphene
"Graphite (named by Abraham Gottlob Werner in 1789 from the Greek (graphein): "to draw/write", for its use in pencils) is one of the allotropes of carbon." http://en.wikipedia.org/wiki/Graphite
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.
Back in 2002/2003 my son used graphite (pencil-lead) to power an 16 light-bulb saltwater contraption for the science fair.
Is Graphene the same as graphite? If yes then why in the hell am I not getting paid by the government for the chemistry lab I set up in my computer room?
Oops, chemistry is fun. We don't need anyone to fund it.
Enjoy,
It's just the normal noises in here.
Sir, graphite is used in pencils. Graphite is made of carbon. Diamonds are made of carbons. Diamond pencils will now replace electrical wiring.
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.
Vote monkeys into Congress. They are cheaper and more trustworthy.
IF you have something that conducts electricty that well, and could wind it up, couldn't you theoretically get a really tiny but super powerful electric motor? There's a lot of cool applications that could come from that. For one, I could have a DVD tray on my PC that could actually mix drinks, besides just hold them.
This is my sig.
Can anyone enlighten me to why copper has gotten so expensive in the last few years. I know its not just copper, but it is the one that effects me and a lot of people the most. The only things I can think of is a war doesnt help, but still dont see that making that huge of an impact and I would guess China might have a higher demand than 10 years ago.. anyone got a real response?
s/©//g
Those kits were great :)
I need to run out and buy some; chances are they won't exist anymore by the time I have kids.
Ahem, perhaps these pencil-pushers should talk to actual chip makers and bakers first before speculating on the applications of graphene. Anything that's only one atom thick isn't compatible with current or any forseeable IC process. Chips have to undergo many heating, cooling, deposition, and diffusion steps before they're done. Anything one-atom thick is going to diffuse away in the process. You also have the reliability problem-- you need reliable connections, millions of them. Anything one-atom thick is going to have too many defects.
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!
Bah, Physicists and their QM simulations! They got it all wrong again. It isn't the length of the graphene ribbon that affects its properties, but the shape of its edges. If you look at benzene ring's molecular orbitals, you'll see that there are two ways to pack them in a ribbon. If they all line up, with resonant transfer going along the ribbon in a straight line, then you have metallic conductivity, with the electron just gliding across all the orbitals without hitting any gaps. If the orbitals don't line up, you end up with little dead ends here and there, which cause "turbulence" and reduce conductivity.
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.
"Pencils son. Pencils." Sorry. The article title is just plain silly.
From the article, it sounds like this only works when the graphene conductor size is a few atoms wide and "one atom thick" -- wouldn't quantum effects become a problem at that scale? Does anyone know or have an opinion whether graphene conductors could be used in a "classical" computer or only a quantum one?
Prov 9:8 Do not rebuke mockers or they will hate you; rebuke the wise and they will love you.
I realize that they're talking about very, very small wires, but how about the big fat 12 gauge suckers in my wall? The price of copper is going through the roof. Is there any chance we can wire up our house with left over charcoal? I love to see the price of copper drop so we can go back to the days when a penny was actually worth a penny (or less).
In tech news today ink jet printers can now produce the nonconductive surface that will be the basis for all new lightspeed chips.
Have Tardis, will travel.
"wouldn't quantum effects become a problem at that scale?"
Quantum effects create the properties those people are looking for.
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Cool, now I can draw my own motherboard, I wonder if you could combine this with different types of lead to make your own special kinds of circuits, but it must suck if you wanna crossover a circuit.
Would it be cheating on a test if I drew a half-adder or an adder and used it to add stuff up on my calculous tests?
Tsukasa: All I really want, is to be left alone...
There is a lot of interest in graphene these days among physicists - if you're interested, Google "massless Dirac fermion" for more info, or check pretty much any recent issue of Science or Nature.
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
I love science with graphite!
If you hook up a pencil lead to a transformer, such as that for toy trains, then turn up the power, it will glow red hot. You can then bend it and let it cool down, and poof! You have a bent pencil lead.
Heat it too much and it has a chemical changeover and stops being conductive.
Meh, I should have published a paper 30 years ago.
(-1: Post disagrees with my already-settled worldview) is not a valid mod option.