New Graphene Research Promises Reliable Chip-Level Production

An anonymous reader writes "A research team from the University of Texas and a German nanotechnology company have published a paper which describes a major milestone for the future of graphene-based computing – the reliable production of wafer-scale graphene measuring between 100 and 300mm, suitable at last for integration with 'traditional' materials in computing. The research team was able to manufacture 25,000 graphene field-effect transistors from lab-produced graphene film on a polycrystalline copper base. Team research leader Deji Akinwande said: 'Our process is based on the scalable concept of growing graphene on copper-coated silicon substrates...Once we had developed a suitable method for growing high-quality graphene with negligible numbers of defects in small sample sizes, it was relatively straightforward for us to scale up.'"(Original, paywalled paper is at ACS Nano.)

Comments

Interesting.

[Anonymous Coward]

I wonder if this will help me 3D print a drone? I was originally going to use Raspberry Pi, but might use a graphene based product instead. I would like to start a delivery service which accepts bitcoin as payment for Apple products.

Re:Interesting.

[NoKaOi]

I wonder if this will help me 3D print a drone? I was originally going to use Raspberry Pi, but might use a graphene based product instead. I would like to start a delivery service which accepts bitcoin as payment for Apple products.

I think you could do it, but you'll need to use nanotechnology.

Re: Interesting.

[Anonymous Coward]

I wonder if this will help me 3D print a drone? I was originally going to use Raspberry Pi, but might use a graphene based product instead. I would like to kickstart a cloud delivery service which accepts bitcoin as payment for Apple IoT products.

Re:Interesting.

[CajunArson]

Can't decide... legitimate troll or bot designed to get +1 votes by vomiting buzzwords and hoping for the best...

Re:Interesting.

[penguinoid]

It's legitimate satire. His "business plan" would be possible to implement before graphene even comes close to fulfilling its "promise". Not saying graphene doesn't have the potential, it's just that sort of thing takes way longer than journalists are allowed by their editors to admit.

Article written by clueless PR bots

[CajunArson]

The non-paywalled article includes some hilarious zingers like "the material also has extraordinary semiconductive properties which could revolutionise the issue of cooling in data centres."

If by "extraodinary" you mean: No bandgap unless you are really doctoring the graphene with other materials, then sure since "ordinary" semiconductors have bandgaps.

Not sure how transistors that can't be turned off will help in cooling data centers, but who knows what revolutions lurk in future press releases!

Re:Article written by clueless PR bots

[Anonymous Coward]

graphene can vibrate faster than silicon. but no it doesn't solve the heat issue.

Re: Article written by clueless PR bots

[Anonymous Coward]

Lower voltage rails?

Re:Article written by clueless PR bots

[ShanghaiBill]

No bandgap unless you are really doctoring the graphene with other materials

Bilayer graphene has a bandgap, and the bandgap can be tuned by applying a voltage, applying strain, etc. Graphene is not a drop in replacement for silicon, and a lot of work needs to be done before it shows up in commercial products. But it has some very interesting properties, and may eventually replace most silicon electronics.

Not sure how transistors that can't be turned off will help in cooling data centers

Well, I don't know about "cooling data centers", but it should result in cooler semiconductors. Graphene conducts heat better than silicon, and if it is built on a copper substrate, with just a few carbon atoms separating the heat generation from the copper, it should be much easier to dissipate heat. That means it can either run cooler, or run much faster.

Re:Article written by clueless PR bots

[Anonymous Coward]

Graphene semi-conductors can run both cooler and much, much faster from what I've seen. There are also different substrates to grow it on, which one will be best is a question.

But there's little question that Graphene could well replace silicon for processors soon enough. Between much higher electron mobility, and thus much higher clockspeeds, better quantum tunneling behavior than silicon allowing Moore's law to continue beyond 7nm feature size, and the seemingly endless interest in the material from corporations and universities I'd bet graphene based processors (and other parts of a computer) will be here within a decade or sooner

Re:Article written by clueless PR bots

[SacredNaCl]

I'm reasonably familiar with the technologies currently used in the chip making process (and always walk away impressed with what they can do), but I don't see how graphene is that superior of a material? What advantages does it really have? A smaller lattice? Can other known materials used in the chip making process truly use a smaller lattice or are we running up against the end here? Or is it just that its lattice has 6 atoms instead of 4 that is has the advantage for trying to put in more transistors on a chip (with a far less straightforward design process)?

I realize the test process is going to be pretty low density until they figure out how to remove it, but I'm unfamiliar with any other advantages.

 

Re:Article written by clueless PR bots

[JasonGoatcher]

Maybe an ignorant comment here, but since diamond has major cooling properties, maybe graphene does too? I've heard about carbon-based cooling for cellphones, you can guide the heat really well using nanotubes. They don't need to be perfect nanotubes, so the tech is already available. Not sure about cost, though.

Re:Article written by clueless PR bots

[JasonGoatcher]

I think with carbon nanotubes you can guide the electrons one at a time, so that would mean significantly less leakage, which would mean significantly less heat, which would mean you could increase the voltage and frequency.

Not sure if the above is a runon sentence, it certainly seems to look okay.

Re:Article written by clueless PR bots

[smaddox]

Graphene exhibits very high thermal conductivity in plane, but that doesn't help much with getting heat out of a chip, into a heat-sink and then into the air.

Graphene as a switch makes very little since (the lack of a bandgap leads to high leakage/poor modulation depth), but there is a chance it will replace or augment metallization in silicon chips. The push to smaller metallization lines has caused several reliability issues which are still not completely solved. Graphene has shown some promise in this area.

Re:Article written by clueless PR bots

[smaddox]

It is difficult to imagine how graphene could replace silicon CMOS when the best lab MOSFETs can't even compete with mass produced Si MOSFETs. High mobility doesn't matter when the off-state leakage current is a couple orders of magnitude higher than in Si. There are interesting theoretical proposals for bi-layer graphene switches which could compete (e.g. BiSFET), but no experimental demonstration that I'm aware of.

Abstract from paper published ACS Nano:

[Anonymous Coward]

Disclaimer: IANAP/C

Abstract from paper published ACS Nano:

Somayyeh Rahimi , Li Tao , Sk. Fahad Chowdhury , Saungeun Park , Alex Jouvray , Simon Buttress , Nalin Rupesinghe , Ken Teo , and Deji Akinwande *
  Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78758, United States
  Aixtron Ltd., Anderson Road, Swavesey, Cambridge, CB24 4EQ, U.K.

The largest applications of high-performance graphene will likely be realized when combined with ubiquitous Si very large scale integrated (VLSI) technology, affording a new portfolio of “back end of the line” devices including graphene radio frequency transistors, heat and transparent conductors, interconnects, mechanical actuators, sensors, and optical devices. To this end, we investigate the scalable growth of polycrystalline graphene through chemical vapor deposition (CVD) and its integration with Si VLSI technology. The large-area Raman mapping on CVD polycrystalline graphene on 150 and 300 mm wafers reveals >95% monolayer uniformity with negligible defects. About 26000 graphene field-effect transistors were realized, and statistical evaluation indicates a device yield of 74% is achieved, 20% higher than previous reports. About 18% of devices show mobility of >3000 cm2/(V s), more than 3 times higher than prior results obtained over the same range from CVD polycrystalline graphene. The peak mobility observed here is 40% higher than the peak mobility values reported for single-crystalline graphene, a major advancement for polycrystalline graphene that can be readily manufactured. Intrinsic graphene features such as soft current saturation and three-region output characteristics at high field have also been observed on wafer-scale CVD graphene on which frequency doubler and amplifiers are demonstrated as well. Our growth and transport results on scalable CVD graphene have enabled 300 mm synthesis instrumentation that is now commercially available.

Re:Abstract from paper published ACS Nano:

[Required Snark]

This is significant progress, but "better" does not mean good enough. Consider the following:

"150 and 300 mm wafers reveals >95% monolayer uniformity". If I understand current process yield amounts, a single layer that is only 95% good is not sufficient for large scale manufacturing. You need lots of layers, and the yield goes down with the product of the percentages for each layer.

"26000 graphene field-effect transistors were realized". On 100mm or 300mm? Compared to current density for VLSI it's many orders of magnitude off.

"About 18% of devices show mobility of >3000 cm2/(V s), more than 3 times higher than prior results ". Wonderful, but prior art was only 6%. What are the values for the other 82%? Are they useful at all?

"polycrystalline graphene". Are their any currently deployed polycrystalline graphene transistor devices? I thought that to make graphene really shine it needs to be more uniform then polycrystalline, hence more a single crystal structure.

So if you think that university press releases are bullcrap, then wanna-be company press releases are significantly lower on the food chain. Cockroach crap? Flea crap?

When???

[buckfeta2014]

Every time I hear about graphite, graphene, bucky balls, nanotubes, and all these other carbon buzzwords, they keep saying "soon soon soon"... Well, what I want to know is when this stuff will leave the research labs and be of any practical use to anyone. Either shit or get off the pot already.

Re:When???

[Anonymous Coward]

Every time I hear about graphite, graphene, bucky balls, nanotubes, and all these other carbon buzzwords, they keep saying "soon soon soon"... Well, what I want to know is when this stuff will leave the research labs and be of any practical use to anyone. Either shit or get off the pot already.

I know, just give us some instant gratification and not all this scientific research shit.

Finally

[Anonymous Coward]

Finally, some hope for the 10 GHz Pentium 4 we have been waiting so keenly!

wafer-scale

[Anonymous Coward]

I am not sold on wafer-scale until they make it web-scale