IBM Creates Ring Oscillator on a Single Nanotube 159
deeptrace writes "IBM has combined CMOS circuitry and a single carbon nanotube to implement a 5 stage ring oscillator. Even though the oscillator runs at just 52 MHz, they expect that it could reach the GHz range with improvements. The frequency of the current oscillator was higher than previous circuits using multiple nanotubes. IBM describes the achievement in the paper "Integrated Logic Circuit Assembled on a Single Carbon Nanotube" to be published this week in the journal Science."
A what? (Score:5, Informative)
Re:A what? (Score:2)
Re:A what? (Score:2, Informative)
How's that?
Re:A what? (Score:3, Informative)
Re:A what? (Score:2)
Oops, that's 12 (13 if you count the contraction).
Re:A what? (Score:2)
Re:A what? (Score:2)
After reading that WP article, I think I'm still asking
Re:A what? (Score:2)
Re:A what? (Score:2, Informative)
Re:A what? (Score:1)
perhaps a diagram?:
NOT gate 1 -> NOT gate 2 -
Re:A what? (Score:3, Interesting)
After reading it, it sounds like a project from one of the Radio Shack electronics kits I had back in the day. One of the components in this kit [ebay.com] was a 7400, a quad 2-input NAND gate. By tying the two inputs of a NAND gate together, it's the equivalent of an inverter. By using one or three of the gates wired in a loop, you could make a one- or three-stage ring oscillator.
I don't recall if the do
Re:A what? (Score:2)
I remember the self-feeding oscillators had very amusing names for an 8 year old: Astable Multivibrator, only surpassed in humor-quotient by Bistable Multivibrator.
Re:A what? (Score:1)
Man (Score:3, Funny)
Re:Man (Score:2)
Re:A what? (Score:2)
Odd... just did this in class today... (Score:5, Informative)
A ring oscillator is a device for making square waves. It uses a common component, a NOT gate. In digital logic, there are two levels, high and low (or 1 and 0, respectivly). High is usually, as far as I have seen, +5 volts, while low is 0 volts (ground).
A NOT gate simply inverts the input. If the value is 1, it outputs 0. If the value is 0, it outputs 1. If the value is somewhere between the two, it will choose one state or the other based on some threshold voltage.
Changing output is not instantaneous. How much time it takes, I don't know. However, it is very fast.
I was going to draw a schematic, but I gave up on appeasing the lameness filter. So, we will use the power of imagination! Imagine one of these NOT gates hooked up to itself. It will switch on and off at a terrific rate. Put a wire on the output, and you have a square wave! Want it slower? Take another two NOT gates, and put them in the loop, so that the first one goes to the second goes to the third. Slower? Another two. If the number of NOT gates was even, the inverted signal would be uninverted by the next NOT gate, which is not what we want.
For more control, one can use a capacitor in a certain arrangment (I'm not looking through my notes). It will take a while to charge and discharge, acting as a delay. Just don't read its voltage as the signal, or you will get a dropping bit, then a rising bit, rather than a nice clean square wave.
Quite useful devices. I hope this clarifies things.
Thanks (Score:2)
Who'd of thought your knowledge would pay off so soon?
Re:Odd... just did this in class today... (Score:3, Interesting)
Re:Odd... just did this in class today... (Score:2)
Now see, this underlines the drawbacks of closed-source. If we could simply have access to the technology that the GNAA and friends of the penis bird use to make their ascii art pass the lameness filter, you could have given us the schematic.
Re:Odd... just did this in class today... (Score:2)
<OT> While I'm at it, by discarding one of the signals, you get a strange-sounding frequency shifter,
Re:Odd... just did this in class today... (Score:2)
Re:A what? (Score:2)
cheap nightlights = ring oscillator (Score:2)
For extra credit, making NOR gates using nightlights is fairly easy but making NAND gates takes quite a
Can you please explain why this is significant? (Score:2, Insightful)
Re:Can you please explain why this is significant? (Score:2)
Even though I understand what CMOS is and nanotubes are.
Ok, maybe that was hyperbole.
Re:Can you please explain why this is significant? (Score:5, Informative)
Re:Can you please explain why this is significant? (Score:2)
Blah blah blah, this does not even get close to explaining to us "lay people" what you EE's are talking about. How about an answer like "Doom 5 will be REALLY REALLY COOL"
Re:Can you please explain why this is significant? (Score:1)
Re:Can you please explain why this is significant? (Score:2)
Re:Can you please explain why this is significant? (Score:2)
to sum up (Score:2)
Re:Can you please explain why this is significant? (Score:2)
It isn't exactly rocket science. Now that they have method for building a nanotube ring oscillator, they can test new chip fabrication processes for using nanotubes for building chips by putting this structure on the chip and using it to measure the electrical characteristics changed. According to the article, they had no way to make these types of measurements
This is significant because... (Score:5, Informative)
OK here's the explanation in 1337:
Carbon nanotubes = t3h w00t
CMOS = reality
Ring oscillator = first tests to integrate t3h w00t into reality
It means that before this, nanotubes and nanotube transistors were only tested in the lab, using microscopic clamps, cables, probes, etc. But this is the first time that a carbon nanotube can be integrated into a working CMOS chip (a small step for chips, a giant leap for mankind). Once CMOS manufacturing can be adjusted for carbon nanotubes, we'll be able to manufacture nanotube memory, nanotube chipsets, and finally, nanotube CPU's!
This is what i've been waiting for since i ever heard about nanotube transistors (however, i think that using graphene sheets instead of nanotubes will be much more effective).
So... (Score:1, Interesting)
Anyway, what is the significance of the low frequency? Is the ring oscillator circuit supposed to be limited in frequency only by process parasitics, so that researchers can determine the maximum frequency the process can sustain?
Microsoft Innovates Too! (Score:5, Funny)
Now let's talk about REAL innovation. Microsoft just announced a new facial feature pack for Office's "Clippy." Now you can customize Clippy according to your facial preferences. Options include complexion, hair style, nose shape and size, and ear/nose jewelry.
Re:Microsoft Innovates Too! (Score:1, Funny)
Re:Microsoft Innovates Too! (Score:1, Offtopic)
Re: (Score:2)
Re:Microsoft Innovates Too! (Score:1)
Re:Microsoft Innovates Too! (Score:1)
Re:Microsoft Innovates Too! (Score:1)
Re:Microsoft Innovates Too! (Score:2)
I tried, it won, so I uninstalled it. Hah! Argue that, Notes!
Re:Microsoft Innovates Too! (Score:2)
It's Mr Potato Clip!
For example (Score:2)
Microsoft's Vista team has invented a new Daisy-Chain Vacillator.
Small, and fragile (Score:1)
It is important to keep in mind that 52MHz is the maximum performance achievable in t
Re:Small, and fragile (Score:5, Informative)
A carbon nanotube (CNT) is a rolled graphene plane (ie, carbon atoms in a hexagonal structure). So of course all current will be on the 'outside' of the tube, as the tube itself really only consists of the outside.
IBM was probaby comparing single-wall nanotubes to multi-wall nanotubes. Multiwall nanotubes are composites of a bunch of concentric single-wall nanotubes. Their better results in the single-wall variety are probably due to less scattering between the graphene planes. A single CNT has a well-defined crystal structure, and is actually quite interesting. The graphene plane itself is sometimes referred to as a 'zero-bandgap insulator', where the density of states linearly goes to zero at the fermi energy (unlike an insulator or semiconductor which has a energy gap at the fermi energy, and hence cannot conduct decently like a metal).
However through changes to the nanotube material, the performance of the nanotube may be impreved.
They probably can get to higher frequencies. I mean, even the vibrational phonon modes of a single nanotube can be in the GHz range or higher (ie, these are the various modes of vibration that the nanotube would exhibit if you struck it, kind of like a wind chime). I don't know specifics, but I don't see why the nanotube couldn't support electronic channels with bandwidths into the GHz or even higher as well.
Although nanotubes do have interesting characteristics different from typical metals and semiconductors. Ie, the electron-phonon interaction goes as 1/T, instead of 1/T^5 (where T is temperature). So at low temperatures there might be useful ways to couple electronic channels to vibrational modes not possible in conventional materials. Or vice versa, the phonon modes might more easily kill off electronic signals. There's alot of interesting work being done with nanotubes, and I'm sure some clever physicists and engineers will exploit these characteristics well in the near future.
Re:Small, and fragile (Score:2)
No, a graphene plane is the hexagonal arrangement of carbon atoms. All nanotubes are made up of this graphene plane.
Carbon nanotubes occur if you take a SINGLE graphene plane and roll it up, connecting it on the ends. Now you are correct there are multiple geometries. You can have wide or narrow tubes. You can also add chirality, by rolling the graphene plane along different directional vectors. And this creates tubes
Re:Small, and fragile (Score:2, Informative)
Actually, you can make nanotubes out of other materials besides carbon. Metallic nanotubes, for example, will have different crystal structures than the graphene hexagon.
A tube with 100 atoms will have 100 distinct oscillating modes.
No, it will have 300, one for each degree of freedom. However, three of these will be translational modes, which are not phonon modes, so really there will be 297 distinct phonon branches. In addition you should distinguish be
Re:Small, and fragile (Score:2)
[slaps forehead]. Thanks, that's what I get for thinking in terms of 1D transport for too long! haha.
Re:Small, and fragile (Score:2)
Not always, for example look up Surface acoustic waves [wikipedia.org]. A lab I used to work at was able to replace a few entire racks of electronics with a single SAW filter that could fit in the palm of your hand!
My point regarding the phonon modes is that they may couple to electrons differently, just like SURFACE acoustic waves vs interior phonons, and may possibly be exploited for interesting effects.
CNT's have much more appea
Waiting on Imprevements (Score:1)
Re:Waiting on Imprevements (Score:2)
Nanotubes.. (Score:2, Interesting)
What exactly this means?
Zero (Score:1, Funny)
Congratulations - you just qualified as a Slashdot editor !
Re:Nanotubes.. (Score:5, Informative)
What the person was saying about nanotubes is they will "turn on" or begin to conduct again after the voltage drops below 0 to a certain negative level. Kind of like a device that takes the absolute value of the voltage, and if it's above a certain value it conducts or switches "on".
Trinary systems? (Score:2, Interesting)
I was going to make a smartass remark about being able to use "new and improved" trinary computers, with positive, negative, and neutral voltages on these transistors, but then I found out they [freeshell.org] already [slashdot.org] exist! [wikipedia.org]
D'oh!
Well, at least I can welcome our ternary computing overlords!
Re:Nanotubes.. (Score:2)
I tried doing that, but it let the magic smoke out.
Note to mods: (Score:2)
Cool! (Score:3, Interesting)
Re:Cool! (Score:2)
Re:Cool! (Score:2)
In other news... (Score:5, Funny)
The findings titled "How to make Clippy more annoying" will be published next week in the Mr. Ballmer's Journal of IBM Bashing
Explanation? (Score:1)
Re:Explanation? (Score:2, Informative)
Re:Explanation? (Score:1)
Re:Explanation? (Score:1)
Re:Explanation? (Score:5, Informative)
Re:Explanation? (Score:1)
Re:Explanation? (Score:2)
Holy Shit!!! (Score:4, Funny)
On a Single Nanotube!
crap all mighty!!!
I'm here to speak out... (Score:3, Funny)
MOD PARENT FUNNY!! (Score:1)
MOD MOD FUNNY!! (Score:2)
They're just showing off (Score:5, Funny)
It's nothing but a token ring.
=brian
Someones gettin laid tonight... (Score:3, Funny)
Re:Someones gettin laid tonight... (Score:2)
Sounds like innuendo to me...
Hey Baby! (Score:1)
Re:Someones gettin laid tonight... (Score:2)
Re:Someones gettin laid tonight... (Score:1)
A nanotube (also known as a buckytube) is a member of the fullerene structural family, which also includes buckyballs.
http://en.wikipedia.org/wiki/Carbon_nanotube [wikipedia.org]
Re:Someones gettin laid tonight... (Score:3, Informative)
Amateur License? (Score:2)
So I'm guessing that they have a Amateur Radio License. I wonder if they can get the nanotube to do single sideband on 6 meters.
Here's why a ring oscillator (Score:4, Interesting)
That's the same circuit mentioned in the recent transparent IC story [slashdot.org] where TFA [deviceforge.com] said
Re:Here's why a ring oscillator (Score:2)
Attention: Question (Score:2, Insightful)
Re:Attention: Question (Score:2)
Most people, including the nerdy and schizo, have no real idea what nanotech is beyond maybe the latest scientific buzzword.
In the meantime; Please don't pat yourself on the back for being a geek. That doesn't play well around here, Holmes.
Nanotube circuits... (Score:1)
Applications. (Score:3, Insightful)
Re:Applications. (Score:1, Insightful)
I believe one of the big problems is the replication that you're speaking of. From my understanding they don't really have a great idea of how to mass produce predictably shaped nanotubes yet. http://www.newscientist.com/article.ns?id=dn8888 [newscientist.com] has a little bit of info on this too.
drain? (Score:2, Interesting)
Surely they mean 'applied to the gate' (the input voltage is gate to source, the output voltage is drain to source)
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Nano Tube? (Score:2)
Also looking for a socket supplier, can't find any on E-Bay.
Thanks,
Rick
Augh, this is really quite simple!!! (Score:2)
People are missing the forest for the (exceedingly small) trees.
Re:Imprevements (Score:2, Offtopic)
Re:Imprevements (Score:3, Funny)
Re:Imprevements (Score:2, Funny)
Re:What we have here is capitalism at its best. (Score:3, Insightful)
Which is why communism fails. If everyone's the same regardless, there's no incentive to innovate. But that's aside the point.
Patents aren't evil, in fact there's nothing wrong with them. It's copyrights that are abused. A patent is to protect your work. A copyright is to extort as much money as possible from something that serves absolutely no tangible purpose. But
Re:What we have here is capitalism at its best. (Score:2)
Re:What we have here is capitalism at its best. (Score:2)
Re:What we have here is capitalism at its best. (Score:2)
Re:IBM IS FAMOUS FOR THIS CRAP (Score:2)