Breakthrough Grows Graphene On Silicon Substrate

eldavojohn writes "A new paper entitled Epitaxial Graphene on Silicon toward Graphene-Silicon Fusion Electronics published by a group of physicists at Tohoku University in Japan has demonstrated that they can grow graphene on a silicon substrate and pair that technique with conventional lithography to create a graphene-on-silicon field effect transistor. For quite sometime we've been discussing the supermaterial graphene being used like silicon improving everything from memory density to transistors. Given this demonstration, are we witnessing the start of a new era in electronics or are there more hurdles to clear before the manufacturers adopt this fabrication process and embrace graphene?"

Not so great

[silverpig]

This isn't a huge breakthrough. First, their dirac peaks, while graphene-like, look horrible. This means the quality of graphene they are dealing with is very low. In fact, they don't thermally decompose all of the SiC, so they're still not much different than the SiC decomposition method. Something like this [arxiv.org] method holds much more promise. CVD growth of graphene on a copper substrate and subsequent rapid etching of the copper yields HUGE 30+" sheets of single to tri-layer graphene films.

2006 called...

[Goldsmith]

Oh hey, 2006 called, and they want their science [sciencemag.org] back.

This field moves *fast* and the epitaxial technique is already being commercialized by IBM (perhaps others too, but IBM isn't hiding it). It's already moving out of science and into manufacturing (for what purpose, I'm not sure anyone knows). Meanwhile, cheaper and larger scale methods to grow graphene have been invented, and are nearly perfected.

Re:What's the strength of Graphene?

[WillDraven]

According to this [unitconverterpro.com] 1 atmosphere = 33.932446552 feet of water.

Re:What's the strength of Graphene?

[silverpig]

Sort of. Actually, it's probably more accurate to say that nanotubes are rolled-up graphene. And yes, graphene is extremely strong. I've seen sheets of it cantilevered out over tens of microns. This is roughly equivalent to taking a sheet of normal paper, holding it in your hands, and having it stick out for well over a football field away from you, perfectly rigid. As strong as it is per unit thickness it is extremely thin (0.34 nm is the number usually quoted), so the total strength isn't useful for armor. After all, graphite is just this stuff layered up millions of times. The 2D mesh is what makes it stronger than diamond because the sp2 bonds are stronger than the sp3 bonds in diamond are.

Re:2006 called...

[John Hasler]

The Science article is about graphene on silicon carbide. This article is about graphene on elemental silicon. Very different.

Re:2006 called...

[the Atomic Rabbit]

The difference between the 2006 work and this one is that the present researchers are not growing graphene on a silicon carbide substrate, but on a silicon substrate with a silicon carbide thin film on top. This may make it a little more commercially feasible.

However, the trouble with the epitaxial technique is that no one (AFAIK) has successfully demonstrated a quantum Hall effect [wikipedia.org] in these graphene sheets, unlike the sheets made using the usual "scotch tape" methods. So there's some doubt about whether what they are getting is really graphene. I don't think the present work addresses this problem either.

Re:What's the strength of Graphene?

[silverpig]

Yeah pretty much. The research I did with graphene was on the "micromechanical cleavage" method (no, not small robot boobs). Basically we'd take a flake of graphite maybe 1mm square, then thin it using scotch tape and then press the tape to a silicon wafer. You can then hunt around for graphene flakes if the wafer has an appropriate thickness of oxide grown on it. The graphene flakes you find in this method are generally 10 square microns, but you can get some that are about 60 microns by 40 microns or so on very rare occasions.

Re:Not so great

[moosesocks]

True, though this would have been a huge breakthrough 1-2 months ago. The paper you linked to was only published on Dec 30 of last year. Prior to that, we had a method to produce tiny flakes of graphene that required an inordinate amount of time, effort, luck, and scotch tape.

Also, graphene would be a lot more useful to us if we could produce it inexpensively on a silicon substrate. The copper substrate stuff is a huge step forward, but we'd ideally like to end up being able to directly grow graphene on silicon.