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Hardware Technology

Making Microelectronics Out of Nanodiamond 80

Science_afficionado writes "Electrical engineers at Vanderbilt have created the basic components for computer chips out of thin films of nanodiamond. These combine the properties of vacuum tubes and solid state microelectronics and can operate in extreme environments where normal devices fail."
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Making Microelectronics Out of Nanodiamond

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  • So are we approaching diamond age now?

    • If we are, whoever has done it isn't talking.

      None of this is nanotechnology as the term was envisioned, though it may be nanoscale.

  • by Culture20 ( 968837 ) on Sunday August 07, 2011 @02:51PM (#37016428)
    Don't turn the ring down. All the best electronics are made out of diamonds this size.
  • Each individual feature is just too big. You're looking at individual transistors 20x or more larger than what we have today on silicon. Faster and lower power, maybe, until you try and build a working CPU from them and discover you need a die 3cm x 3cm. Niche products only.

    • The first semiconductor transistors were large enough to handle a single one with your hand. What makes you assume that the nanodiamond transistors cannot get smaller?

      • Re:Size matters (Score:5, Informative)

        by slew ( 2918 ) on Sunday August 07, 2011 @05:08PM (#37017300)

        The first semiconductor transistors were large enough to handle a single one with your hand. What makes you assume that the nanodiamond transistors cannot get smaller?

        There are unfortuantly some additional physics problems that need to be address for miniturization of this technology.

        One issue is the free-space electron transport. With silicon technology, the "channel" is doped silicon which carried the electrons (like a wire). The channel sort of acts like a waveguide for the electrons as the travel between the source and the drain (assuming common mos technology). In "free-space" transport between the cathode and anode (vacuum tube and the proposed nano-diamond transistor), you need to keep some sort of physical separation (in an all-free-space design) or some sort of electrical isolation betweeen devices (shielding).

        The second issue is the structure. In the proposed diamond design, the diamond "circuitry" is patterned so that it is essentially carved to have structures above the silicon dioxide surface (as opposed to standard patterning which is either directly on the surface ion implated into the substrate). This nano-tech like structure will of course need to scale to get better. If they can take anything from the current silicon technology, shrinking in 2D (patterning) is much easier than shrinking in 3D (needed for reduced gate thickness needed to improve gate channel efficiency). In advanced silicon technology, 3D scaling has be all but abandoned in favor of techniques like tri-gate/fin-fet...

        Note that I'm not saying these advances aren't possible, but they do not leverage any current manufacturing techniques, so it's likely that this stuff will be in the lab for a while whilst current technology will advance. When it does become feasible, it may or may not be competitive. This is not unlike ferro-magnetic ram might replace dram someday, or how solid state memories will replace rotating disk memory someday... Maybe someday, but it's equally possible that day may also never come or be so far out that other new technologies may gain a foothold (e.g., how RRAM might actual displace FRAM as the DRAM successor)...

        As a silly example, if you invested the same amount of "area" in some farady-cage-like shielding of present day CML (current-mode-logic) technology electronics, would this nano-diamond technology be much better? I dunno, but these new-fangled technologies need to beat these kind of tweaks of current day technology to win. But of course we have to both try to do new things and try to improve old things and see which one comes out on top. However to assume that the appropriate technological and manufacturing advances will necessarily come to pass to make a general approach viable would be a mistake as a heap load of abandoned technologies will certainly attest to...

        • tl;dr version: this future technology can't use today's manufacturing techniques so it's not yet ready to go mainstream. And we don't yet know if the future technology will beat out the future version of today's technology.

          In other words, just like every other promising future technology out there... at least until it does become mainstream, or falls by the wayside because of impracticalities.

          • ..actually, the article states that this technology could be manufactured with current machinery, just modified to do so in a vacuum.
            • I was tl;dr'ing the (GP) comment - and in that also attempting to point out its negative/pessimistic mindset.

        • Of course, leakage currents are a big problem for silicon transistors as well, and with current technology we are already quite close to the limits of silicon transistors. Of course there's new developments going on for silicon as well, and it's a given that we can't know which future technology will win out.

          Also, the article mentions that the diamond transistors are faster; unfortunately I couldn't find how much faster. However, given that modern processors use the miniaturization mainly to cram more cores

    • by ColdWetDog ( 752185 ) on Sunday August 07, 2011 @04:00PM (#37016892) Homepage

      Each individual feature is just too big. You're looking at individual transistors 20x or more larger than what we have today on silicon. Faster and lower power, maybe, until you try and build a working CPU from them and discover you need a die 3cm x 3cm. Niche products only.

      Here is the clincher:

      The nanodiamond circuits are a hybrid of old fashioned vacuum tubes and modern solid-state microelectronics and combine some of the best qualities of both technologies

      Just as soon as the audiophile industry hears about this they'll go batshit insane. Something that is 1) new 2) expensive 3) combines tubes and anything else will be simply irresistible to them. Bonus points for diamond covered wooden knobs.

      • by mcgrew ( 92797 ) *

        Just as soon as the audiophile industry hears about this they'll go batshit insane. Something that is 1) new 2) expensive 3) combines tubes and anything else will be simply irresistible to them.

        I know, you jest, but judging from TFA they're only talking about the diamond transistors being able to withstand heat like tubes do.

        Musicians use tube amps because tubes overload differently than transistors; the wave distortion is different. Overload a transistor or a tube with a sine wave and both will produce a s

    • The extreme temperatures/radiation niche is a real and valuable one, particularly as these devices will cost a fortune at first.

      Also, the 8-bit CPUs of thirty years ago should be quite feasible. From there, we'll see what can be squeezed out of physics ...

  • by schwit1 ( 797399 ) on Sunday August 07, 2011 @03:03PM (#37016506)

    "Potential applications include military electronics, circuitry that operates in space, ultra-high speed switches, ultra-low power applications and sensors that operate in high radiation environments, at extremely high temperatures up to 900 degrees Fahrenheit and extremely low temperatures down to minus 300 degrees Fahrenheit."

    Why not use this design for consumer products? All the way around it's a better design. I'd cough up a few bucks more for this chip.

    • Read the fine print on the images that give the scale of the "electronics". The transistor seems to be in the mm-range. Perhaps with time, the process might shrink.

      Anyways, if you are ready to pay extra then - almost by definition - you are not looking for "consumer products" :)

    • by eqisow ( 877574 )
      Because I'm sure there will be a sizable size/speed trade-off, at least to begin with.
    • by c0lo ( 1497653 )

      Why not use this design for consumer products? All the way around it's a better design. I'd cough up a few bucks more for this chip.

      Consumer products needs holy smoke to operate (otherwise how would one tell the chip is broken?). This one... needs vacuum to operate.

    • As soon as Nvidia hears about this, they'll probably buy the technology -- and market their GPUs to Eskimos with the selling point that they double as space-heaters.
  • Did they watch Eureka a couple of seasons ago...They had a thing called a "Logic Diamond"
  • that's easy stuff, they should try the other way around: nanoelectronics out of microdiamonds.

  • You can't make vacuum devices with holes, so there are not the complementary devices needed for CMOS like operation. We would be working with a technology similar to N-channel FETs, with all the problems of low-output state power dissipation. It won't scale to high integration levels. That said, the technology probably has niche applications in high temperature and rad-hard environments.
  • by uid7306m ( 830787 ) on Sunday August 07, 2011 @04:43PM (#37017156)

    I did research on this stuff back in the 1990s. Made the films, did the vacuum chambers, had the world record for emission efficiency for a while. While it may have some niche applications, the basic problem is that it is *not* a low-voltage technology. Modern chips operate on 1.5 V or so; Diamond devices will be more like 5V. So ultra-low power? Nope. They say that the devices are more efficient because the electrons don't bump their way through the silicon crystal lattice. While that's true enough, it doesn't actually make a big difference. Why? Because the electrons very much will dump all their energy when they leave the vacuum and hit the anode.

    Ultra-high speed? Again, while vacuum is nice in that it doesn't slow down the electrons, that turns out not to be a big effect. The most important factor in speed is the size of the device, and there is certainly no reason to believe that these vacuum tubes will be smaller than transistors, if built with the same lithography tools. I may be wrong, but I have good reasons to believe that they will be harder to make small.

    High temperature? Radiation resistance? Maybe, but that turns out to be a complex question. These devices aren't just diamond and vacuum. They involve insulating layers, too, and those insulators may be affected my high temperatures or radiation. Essentially, a device is as robust as its weakest link, so until you can make the entire device out of truly robust materials, you won't gain too much.

    So, it's nice work. I know how hard it is to do this stuff. And, it might be useful eventually. But it won't revolutionize technology any time soon. And, those guys ought to realize that, if they would let themselves. Research lives off publicity these days, because it is being forced to become more and more of a competition between groups. The trouble is, when competition enters and your salary depends on the claims you can make, truth tends to be (shall we say) over-inflated.

    That darn free market ideology messes up science. I like it as much as anything for people who make spoons or telephones. But science isn't making spoons. If you get a bad spoon, you'll know it, but if you read an exaggerated research paper, how can you tell, other than by doing the research again? And, that's just not efficient: doing it wrong and then doing it again isn't nearly as good as doing it right the first time.

    Oh well. Enough ranting.

    • I'll second this. I actually took classes from Dr. Davidson (lead researcher) over a decade ago, and he was shooting for the same goal back then. The approach seems to have changed - using CVD now instead of cut, polished, and etched diamond crystal (just like silicone) - but it doesn't sound like they're any closer to having solved some of the more practical or marketable problems outlined above.

  • I have a feeling the vacuum requirement is going to be a bigger problem than the article implies. It is not just a matter of manufacturing the device in a vacuum, it is keeping the materials from sublimating due to a dissociation constant of the hydrogen embedded in the substrate. The amount would be microscopic, but that is a lot when you are taking nanoscale. And gas would not need to flood the device, just a small amount could render it unreliable, depending upon the application. I'm sure some would
  • I'm wondering how resistant to EMP electronics made out of this would be.

  • So how is "nanodiamond" material different from graphine?

    G.

    • Nanodiamond is basically polycrystalline diamond whose individual crystallites are, say, ~10 to 100 nanometers in size. It's still tetrahedrally-bonded carbon (the sp3 carbon bond that defines crystalline diamond) with some non-sp3 stuff (sp2, amorphous C, etc.) in the grain boundaries.

      Graphene is single-layer sp2 bonded carbon, think of it as a single layer of graphite. Flat, chicken-wire skeleton, with the same type of bonding you find in pencil lead or other forms of graphite. Very different from diam

  • As Nitrozac wrote: Tubes Rock!

    (I wore out my t-shirt.)

  • Zed: A receiver must be like a transmitter. I think you're a crystal - in fact this one! This diamond! In here, there is infinite storage space for refracted light patterns. Yes or no? The Tabernacle: You have me in the palm of your hand! From Zardoz.
  • by YetAnotherBob ( 988800 ) on Monday August 08, 2011 @11:43AM (#37023890)

    I remember reading about this kind of thing in the mid 1990's. Scientific American reported on it. At the time, they were making diamond films on ceramic substrates. the diamond was grown by creating a carbon atom plasma and shooting it at the substrate. Shock plasma deposition of the carbon. It wasn't very efficient. They hadn't worked out too well how to mask and etch the films, so they were using electron beams tp cut into the diamond, then adding the dopant. That limited the size of the device produced. The device was around the diameter of a pencil eraser. The researchers (in Japan, if I remember correctly) were predicting commercial development in as little as five years. Well, I never saw anything come of it.

    I was looking forward to that coming out too. I am an electrical engineer, and have worked for a long time with plans for building facilities and power lines and so forth. The device made in Japan was a single SCR (silicon controlled rectifier) that would work just fine at 600 Volts, and a little over 200 Amps. It operated at a temperature of a little over 600 degrees C, but still, an SCR can be used for many power applications. That single SCR was controlling a around 120KW. For big AC to DC power lines, we use SCR banks where each of the SCRs operate at about 24 Volts relative to the next SCR in the stack. This for stacks that go up to 750 KV. The stacks are paralleled to get the current that actually goes out over the line. One such line goes from Washing State to LA, and carries close to 10% of the total power used by LA. for what I was doing at the time. These diamond SCRs would have made a great speed control motor starter. At 480 VAC, we could have made the controller with six SCR's, three fuses, and a disconnect switch, plus a small PLC board. The control station would be bigger than the controller. Typical controllers for this type of application on say a 100 HP motor are around 7 feet tall, 4 to 10 feet wide and 3 to 6 feet deep. reducing this to 2 Feet wide, 3 feet high and 1 foot deep would free up a lot of space. This, if purchasable, would have given me a lot more freedom in placement. If I could reduce the size of the controller, the process people would have loved to use the extra space. I could have used that to justify spending up to $100,000.00 more for the device, in some cases.

    We could really use such a device in industry. There are a ton of uses that I could think of off the top of my head. Used as an ultracapacitor controller, it would enable a single capacitor, the size of a couple of C cell batteries to store more power than a car battery. A large electronically controlled circuit breaker, with custom controls, and a quick action would also help to save a lot of equipment and lives.

    There were a couple of real problems with it, though. First, it's flammable. The actual electronics would need to be isolated from any contact with oxygen. Encapsulation would do that. Real Graphene computer chips, which I would expect to see before this matures, would also be flammable. But, there are more options for protecting those, because of the relatively lower temperatures.

    Also, the Diamond SCR's operated at temperatures higher than some common conductors can withstand, and well above the temperature at which Diamond burns. There would have to be special connectors, and cooling systems. That heat, even if from a small eraser sized element needs to go somewhere. Ultimately out into the environment.

    Second, it's apparently not an easily commercialized process or material. I am seeing more reports of Diamond film growth, and also of graphene film growth and production. That is a good thing. Graphene seems to be moving towards fabrication faster than diamond. I would like to see both happening. I have also seen recently, that very low impedance conductors have recently been made from carbon nanotubes. While not room temperature superconductors, if they have lower conductivity than copper, I would really like to be able to specify them. Cost would be a factor there. Bu

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