Tuesday, April 22, 2008

Hype overshadows graphene's real promise

Graphene is in the news again, with the announcement that researchers at the University of Manchester have demonstrated (PDF) a graphene-based single electron transistor. That's an exciting development, but the hype machine immediately went completely out of control. Wired declared that Moore's Law is saved, while less restrained corners of the blogosphere announced that "silicon is out, carbon is in".

Well, not exactly. First of all, most of the devices in question were measured at 0.3 K, not exactly a practical temperature for commercial electronics. Second, the whole point of the referenced paper is that the behavior of Dirac fermions(*) under such extreme confinement is chaotic. Somehow I don't think the CMOS industry is quite ready for design models based on quantum statistics. And finally, all of these experiments used mechanically exfoliated graphene, which is a fancy way to say "we rubbed a pencil lead on a silicon wafer and told a grad student to find the graphene flakes." Again, not a commercially viable strategy.

This is not to denigrate the very interesting work being done at the University of Manchester and elsewhere. Graphene is an excellent system for important studies of very fundamental physics. But researchers have a long long way to go to develop a commercializable process, much less make a noticeable dent in the silicon market. Let's keep our expectations in line with reality, shall we?

(*) What's a Dirac fermion? Did I mention that carriers in graphene don't behave like normal electrons?

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