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Technology Science

Circuits Better with Purer Nanotubes 113

Posted by CowboyNeal from the now-that's-good-nanotube dept.
Mark_Uplanguage writes "PhysicsWeb has an article on improving techniques for the use of carbon nanotubes in electronic circuits. From the article, 'Physicists in the US have developed a new method for making electronic circuits with carbon nanotubes. The technique involves dipping semiconductor chips into a purified solution of nanotubes, rather than the conventional method of growing the nanotubes directly onto the chips. The resulting devices are much better than those produced by other approaches.'"
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Circuits Better with Purer Nanotubes More

Circuits Better with Purer Nanotubes

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  • Nano computing here we come!
    • Not really sadly, that's what I thought at first but it seems it's just about using the nanotube electrical properties. The chip is the same size but the conductive element will be nanotubes, which is still a great thing since it offers no resistance (almost) to electrical current. Obvisouly the purpose of their research is further miniaturization but as of now, in this research, they still work with conventionnal size chips.

  • That's a neat graphic in the article... (Score:3, Interesting)

    by Adult film producer ( 866485 ) <van@i2pmail.org> on Friday August 05, 2005 @07:59AM (#13248386)
    what the hell does it mean though ?

    http://physicsweb.org/objects/news/9/8/2/050802.jp g [physicsweb.org]

  • ...the Chipsicle!
  • The technique involves dipping semiconductor chips into a purified solution of nanotubes, rather than the conventional method of growing the nanotubes directly onto the chips. The resulting devices are much better than those produced by other approaches.

    It is like dunking your doughnut in coffee instead of waiting for the doughnut to naturally produce its own coffee flavour.
    The more you know.

  • What they don't discuss (Score:3, Informative)

    by 2.7182 ( 819680 ) on Friday August 05, 2005 @08:03AM (#13248395)
    That there are quantum mechanical problems with having the tubes alligned and getting a good signal through them.

  • Any More? (Score:5, Interesting)

    by irokie ( 697424 ) on Friday August 05, 2005 @08:05AM (#13248398) Homepage
    does any one have a link to an article that's more than just a blurb? What are the applications? How long before we can built Logic out of these chips? According to TFA, all they've managed to create so far is an FET...
    • ANFET? And here I am using PFET and NFET like a sucker.
    • Expect organic electronics to start replacing inorganic (i.e. silicon) quite soon. OLED displays are already on the market. Polymer solar cells that look like a big clear plastic tarp uses a special nanotube called a "buckeyball" (aka C60 carbon nanotube, buckministerfullerene, fullerene, etc.) to help with the light conversion process. The technology is here and now. Manufacturing issues are what's holding everything up. That, and the fact that organic semiconductors are p type semiconductors only (th
    • There have been many application unfortunately they haven't reached a stage of commercial production on a large scale. In my graduate study, I did a project on Carbon Nanotubes and applications. Here is a site that shows applications of nanotubes in animation.

      http://www.photon.t.u-tokyo.ac.jp/~maruyama/agalle ry/agallery.html [u-tokyo.ac.jp]
  • computing is just around the corner ... of course, it'll take 30 or mroe years to get to us mere mortals, but you can bet the US military / industrial complex will have this soon, if they do not already possess them ...

    • Re:Quantum scale ... (Score:3, Informative)

      by hcdejong ( 561314 )
      Right. Just like the US military / industrial complex had been using silicon chips for 30 years before the Altair, or vacuum tube computers 30 years before the first commercial computer.

      FYI, the timeline:
      1943: Colossus
      1946: ENIAC
      1958: first IC
      1971: first CPU
      1975: Altair
    • of course, it'll take 30 or mroe years to get to us mere mortals

      That's not necessarily true. If they can make $$$ by mass-marketing it to us 'mere mortals', they'll do it.

      By way of example, look at the sophisticated microprocessors that are marketed to us 'mere mortals'.

      It's all about profit.

    • Man the military-industrial complex is SO 1960's, now it's the PLM, Political, Legal, Media, complex that we worry about. All hail the Senator from Disney, and Mickey Mouse's perpetual copyright protection!

  • A solution of nanotubes? No such beast! (Score:3, Insightful)

    by bigsteve@dstc ( 140392 ) on Friday August 05, 2005 @08:08AM (#13248410)
    The article says it is a solution containing nanotubes, not a solution of nanotubes.

    And if the nanotubes were in solution, they wouldn't be nanotubes any more.

    • OK, they used the wrong word. They should have said "a suspension containing nanotubes".

    • Re:A solution of nanotubes? No such beast! (Score:4, Informative)

      by aug24 ( 38229 ) on Friday August 05, 2005 @09:05AM (#13248641) Homepage
      if the nanotubes were in solution, they wouldn't be nanotubes any more.

      Not so. You can have macromolecules is solution without destroying them. For example, fullerene dissolves in toluene. The molecules don't break up, but they acquire a coating of toluene molecules on the surface which means that they act as part of the liquid instead of a solid. When the toluene is evaporated, the buckys are fine.

      In fact, there's a good chance these nanotubes are bucky-derived so they might even be in a toluene solution in TFA (which I haven't read cos I don't care about chip manufacture, I was just reading for the '+5 Funny's).

      J.

      • Technically, isn't that just a suspension, not a solution? I think that's the point the other guy was trying to make. The fullerene isn't chemically reacting with the toluene, as opposed to adding salt to water which ends up giving you free floating Na+ and Cl-.
        • You're talking specifically about an ionic solution - you can have anionic solutions too. In a suspension you should be able to get the stuff out by, say, centrifuging, but in an anionic solution (or, obviously, an ionic one) you won't.

          J.

  • are there any practical nanotube applications (Score:1, Insightful)

    by Anonymous Coward
    that are actually on the market right now ?
    all i ever see are "may" or "might" or "could"
    lots of hype/vapour but i havent heard or seen any applications of this technology that have made it to market

    perhaps they will be released with Duke Nukem Forever as an addon

  • Interesting Chips Debate (Score:5, Funny)

    by fruey ( 563914 ) on Friday August 05, 2005 @08:15AM (#13248434) Homepage Journal

    The technique involves dipping your chips into a purified solution of ketchup, rather than the conventional method of throwing the ketchup directly onto the chips.

    So, are you a dipper or do you cover them with sauce first? Science have proved that the dippers are using a superior technique...

    chips: n. [British] Fried potatoes cut into thick rectangular strips. see fries [American].

    • Ketchup goes on fries, malt vinegar goes on chips.
    • Comment removed based on user account deletion
      • has a cross sectional area approximately 4 times larger than the average American Burger Restaurant Fry

              It's called hyperthreading...
      • We used to call them shoe-string fries, back when regular fries were regular sized like what your getting now, probably has something to do with McD's over engineering every aspect of food to cut cost and increase production. Great now I'm craving fish & chip, hafta make a trip to Canada I suppose.
    • Actually, what are referred to as chips in Britain aren't really what we'd call fries over here. They're much too thick. I've always heard them referred to as "JoJos" or potato wedges.
    • They're a lot like what we call "Steak Fries" here in the US. I generally prefer them to the thin fast-food kind, but done properly, they're all good.

      Remember everyone, don't buy those frozen par-cooked ones. Cut 'em fresh, blanch them in 250-275 degree oil, drain, then fry at a higher temp (365 works for me). Oh yeah, and if you want 'em REAL good, fry them in some sort of animal fat. Otherwise use Peanut Oil and only that.
      • You prefer them blanched in oil? Too greasy that way. Better to boil them until really soft and then fry at a very high temp. Or would they not count as fries to you then, being mostly boiled? :)
        • Blanched properly, they won't soak up much if any oil at all. As long as there's moisture coming out at a decent rate (steam), it's hard for oil to get in. The idea is to blanch them until they're slightly tender, but not cooked all the way through. Then you drain them for 10-15 mins, which lets most of the surface oil drip off. Then you fry again at a high temp until golden-brown, probably only a few minutes since you blanched. If you blanch too long, you'll have soggy fries from the oil. Too little
          • hmm, makes sense. My grandmother always used to use oil totally and they were horrible... too low a temp for too long, my approach just means you cook the potato through, and just fry it hot for taste and texture. I may give that a go though.
      • I have been trying the two step frying method, but haven't achieved satisfactory results. Could you share more detail about the first frying session, such as how long for what mass of fries in what volume of oil, what do you do with the fries immediately after? Also, do you have a second pot of oil kept at the higher temperature, or do you work with one pot?

        I tend to cook around 3 pounds of potatoes at a time in small batches, using a kitchenaid french fry slicer [shop.com] (sorry- can't find it on ki
        • I use one pot, literally a pot with oil in it and a thermometer. I would suggest trying to blanch at 260 or so, and not until they float, because at that point they're cooked. You want to get them slightly translucent then pull them out of the oil. Always do small batches, then allow to drain thoroughly (about 10 mins) on a wire rack (or paper towels if you don't have a rack). Then crank the oil to about 375 and fry until golden brown.

          I guess what's going wrong for you is that you're blanching at t
    • So, are you a dipper or do you cover them with sauce first?

            Covering your chips in sauce is a very useful way to prevent chip theft when you live with someone who is allergic to tomatoes...
    • Stop it, you're making me hungry you insensitive clod!!!
    • chips: n. [British] Fried potatoes cut into thick rectangular strips. see fries [American].

      Or "potatoes cut into thick rectangular strips and then fried". Cutting fried potatoes to make french fries would be kind of silly. :) (Incidentally, in French you use the same word as Americans do for chips, though it's pronounced like "sheeps". They also say "frites" (or "pommes frites"), which means the same thing as "fries" (or "frieds", I guess).)

    • Throwing the ketchup directly onto the chips works best when you're driving with one hand, squirting all the ketchup into a pile to be dipped is dangerous, it usually ends up all over the floor. I wish they would start putting ketchup in those little BBQ sauce containers. Damn it!

  • What it means (Score:3, Interesting)

    by standards ( 461431 ) on Friday August 05, 2005 @08:23AM (#13248458)
    Just a word of warning for those not familiar with this advance - there are still a lot of issues to be worked out to being this technology into the field.

    My group estimates that it will be 10 or more years before we see this technology impacting consumers around the world.

    We all want much more powerful CPUs in a smaller package disapating little heat. But so far built only a few transistors using said technology - far from the density and complexity of a next generation CPU. The reliability of the process needs to be made very very high, orders of magnitude high, in order to make a next generation CPU using this technology... and those techniques are far, far away from being available today at any high volume chip fab facility.

    Don't get me wrong - its an important scientific advance, but the manufacturing process still needs a lot of new science to make it happen in a way we'd like to see it.

    • Re:What it means (Score:1, Funny)

      by Anonymous Coward
      So 10 Years from now we can have an even smaller gameboy!??

      Primal_theory
    • Your group?

      What are predictions based on?
      I mean, 10 years with current R&D efforts or 10 yrs with massive inceased R&D?

      nano being a buzzword, in many respects, but I guess the field is expanding quite rapidly, how hard is it to do predictions?

      • I can only tell you that it is similar advances have taken about 10 years to hit the fab facilities that we've been associated with. Of course some hit the street sooner, and some never make it to production due to an orthogonal advance or an insurmountable implementation problem.

        Obviously, someone could make a full-court press and invest a few extra billion to make it (potentially) happen faster. But in general it isn't though of as being wise, as it could be a huge money sink that doesn't pay off the in

      • It's pretty fucking hard.

        But hey, predict something easy. When will the PS3 be released to the US market?

        See what I mean?

  • Weird (Score:3, Interesting)

    by jurt1235 ( 834677 ) on Friday August 05, 2005 @08:24AM (#13248463) Homepage
    So you have nanotechnology in use, but for a production application you will use the technology by just dipping the, in this case computerchips, into the liquid, instead of carefully placing everything on the chip how it should be.

    Suppose this works because there are hooks on the chip on which the nanotubes get stuck. How do you know that two opposing hooks attach to the correct same nanotube, and not to the wrong nanotube, or to two nanotubes with no connection at the other end at all.

    I think this works nice in a lab where you only measure certain performance parameters from the use of nanotubes, but that a real chip will not work with this method.

    Pure nanotubes work better: That is to be expected based on the properties of a nanotube (guessing here). I think an assembling method to place the nanotubes so you are sure they are at the correct place, is a better direction for this research than a huge chip dipping facility. If they want to do the last they will have to get a license from Pringles anyway, they have the best dipping shape for chips.
    • Um you do realize that they basically make chips by shining light(s) through a mask [think overhead projector] then a lense [or vice versa] onto a PHOTO SENSITIVE chemical that they then wash off right?

      Nobody sits there and "places transistors". They're made by the bulk and yes they do have a significant throwaway percentage.

      If you walk away with 300 of 540 P4 dies on a 300mm wafer I think they call that a good day [it's probably higher than that I imagine].

      Tom
      • Yep, but that is washing of the photosensitive coating, and adding a new coating. That is just a global layer for throw away purposes. This is using the coating to stay behind at very specific locations. It looks very different to me since the tubes are premade components in this case which they do place on the chips, instead of having the base material and etching away layers of it.

        And yes, a certain percentage breaks in the proces, and a manufacturer even rates it fabs according to how much breaks (with
        • I don't see the difference, you're relying on the coating to be smooth and uniform for the die to work now...

          This is basically going backwards. Provided your coating is even you should get the tubes in ever "nook and cranny".

          Tom
          • But for the tubes to work, they have to be hooked up correctly, that does not seem garanteed with this method. For the coating to work, it "just" has to be uniform (Not to easy either).
    • http://physicsweb.org/articles/news/7/11/13/ [physicsweb.org]

      I'm not pretending to have a very good grasp on how this all works, but it seems like these guys have developed some pretty precise control over where the nanotubes get placed by using DNA. Kinda takes 'organic computing' to a whole different level, doesn't it.

  • One of a dozen daily.... (Score:3, Interesting)

    by Solipson ( 863548 ) on Friday August 05, 2005 @08:44AM (#13248534)
    ... press releases about breakthroughs in nanotech especially in the carbon nanotube/semiconductor field. One should know that the US, EU, Korea and Japan throw an unprecendented amount of money into research in this field right now. And as the yanks have set the success metrics, it means all the researchers have to do is churn out press releases and file patents :-) So, don't hold your breath re dipping, licking and roasting electronic circuits with CNT's.

  • Clarification... (Score:5, Informative)

    by wikdwarlock ( 570969 ) on Friday August 05, 2005 @08:53AM (#13248571) Homepage
    These are not "purer nanotubes". They are more nanotubes and less other junk. Nanotubes grown on a surface will tend to also create other carbon molecules like ash, diamond crystalites, and even buckyballs. The purified stuff is simple this same mix of materials, but filtered to only have the tubes. They're still the same quality of tubes, just not dilluted w/ other crud.
    • Dude....you've just basically given a definition of "purer." More nanotubes, less junk. "Not diluted w/ other crud" == "purer". What is your point?

      Whoever modded this guy informative doesn't know squat.
      • I think the point is that the solution is purer, not the nanotubes themselves.

        ...I think.
      • Nanotubes are highly ordered forms of carbon. As such, they can have varying purity. If one of the bonds of a carbon atom in the tube is strained too much (bent, pulled, heated, hit by radiation, etc.) it may break and distort the perfect shape of the tube. A "pure" tube is theoretical only. There's always going to be some slight imperfection in the atomic structure of the tube. My point was that "purer nanotubes" implies that the quality of the tubes was high (few defects). But what they've really do

  • Carbon is a semiconductor (Score:3, Interesting)

    by lcsjk ( 143581 ) on Friday August 05, 2005 @10:10AM (#13249310)
    Electronics have now evolved through the semiconductor portion of the periodic table of the elements. The early crystal radios used element 82,lead sulfide (galena from wikipedia), then during the early 1900, the so-called foxhole radio used razor blades and pins made from element 50,tin, to make a crystal. Early transistors used element 32,germanium, and integrated circuits moved onto element 14, silicon. The nanotube technology is now moving us to the last of the series which is element 6,carbon. This progression from lead to carbon is also a progression from larger molecules to smaller molecules and fewer elecrons. It took about 50 years to get to silicon and another 50 years to get to carbon. Where will we be in another 50 years?? (Don't be funny and say dead!)
    • Carbon isn't a semiconductor and isn't functioning as a semiconductor here.

      Carbon is either a good conductor (nanotubes, fullerenes, graphite) or a good insulator (diamond).
      • Technically, that's not the whole truth. Carbon in graphite form
        is a semimetal at room temperature (has nearly zero
        temperature coefficient of conductivity); at lower temperature
        it is a semiconductor, at higher temperature it is a conductor.
        The high temperature behavior is similar to a semiconductor
        'going intrinsic' (Germanium does this at an inconveniently
        low temperature, Silicon goes to several hundred Celsius
        first).

        No one used graphite semiconductors much because the
        lattice is VERY strong in one dimensio
    • So why instead of focusing on these nanotubes don't they instead focus on building circuits with diamonds? I was under the impression that things were doing better in the synthetic diamond camp.

  • What is new in here ? (Score:4, Interesting)

    by karvind ( 833059 ) <karvind.gmail@com> on Friday August 05, 2005 @10:21AM (#13249441) Journal
    I am sure researchers working on CNT (carbon nanotubes) will back me up on this. But what is new in here ?

    (a) No, these transistors are no better. If you check the nature article, the contacts to the transistors are still lousy (technically, they are still schottky and not ohmic). And contact resistance is too high.

    (b) No, they don't really get the nanotubes where they want as claimed in the article. The alignment using this technique is still worse (will require substantial effort to make it better).

    (c) One of the bigger drawbacks which was conveniently ignored was the fact that they still cannnot control the number of tubes between the two contacts. So it can be 1 or 2 or 5 and so your current or other properties will vary that much. This technique doesn't make this problem any better.

    (d) Last but not the least, no comment about the role of oxygen. All other researchers struggle due to hysteresis behavior, these devices look similar to them.

    • Precisely. As someone who has been involved in biotech and nanotech for more than a decade the comments above by karvind sum up the situation quite well.

      Submissions to /. on these topics should be submitted to those who can evaluate them before they pass into the /. approval arena.

      The situation with nanotube wiring can be summed up very simply -- how the fuck are you going to lay them down and connect millions (or billions) of them? If the topic cannot answer that then it is unlikely to be of interest to
  • Speaking of better/faster/cooler chips ...

    Whatever happened to all the hype a few years back (a WIRED cover-story comes to mind) about how we would be seeing chips formed from synthetic diamond rather than using silicon ... in order to improve performance and handle heat more efficiently?

    Haven't heard much of anything on the 'diamond age' since ... did the DeBeers just off all those guys?
    • cool advances in diamond semiconductors continue [aist.go.jp] By the way, gem quality carbon crystals are already a reality. Funny DeBeers and other diamond cartels are funding development of machines that can distinguish natural diamond from synthetically created carbon crystals (not hard, natural diamonds have "inclusions"), and propoganda that of course your loved one would much rather have a "real" diamond and man-made carbon crystals aren't diamond. Oh, yeah, what would you like dear, a half-carat natural di
  • used for drug delivery, as announced today by the National Academy of the Sciences (NAS).

    But, hey, nanotubes are good - provided they don't fall apart and clog your bloodstream, right?

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