Interesting read! I'd like to highlight a couple of points:

“Carbon nanotubes, borne out of chemistry, have largely been laboratory curiosities as far as microelectronic applications are concerned. We are attempting the first steps towards a technology by fabricating carbon nanotube transistors within a conventional wafer fabrication infrastructure,” said Supratik Guha, Director of Physical Sciences at IBM Research. “The motivation to work on carbon nanotube transistors is that at extremely small nanoscale dimensions, they outperform transistors made from any other material. However, there are challenges to address such as ultra high purity of the carbon nanotubes and deliberate placement at the nanoscale. We have been making significant strides in both.”

So they are currently – oh no: 2012 – attempting the first steps on this path. Unfortunately I don't know how long and how steep that path might be. At the end of this path IBM expects or knows to achieve transistors that outperform transistors made from any other material, which would includes GaAs. So the expectations are high! Still I wouldn't expect a product or a fabrication process anytime soon, because there are challenges to address. Having achieved significant stride sounds good but by far not as good as handing out chips to prospective partners – as POET is able to.

It is noticeable that the article does not mention the word cost (at least not in the context of carbon nanotubes). How much would it cost to produce carbon nanotube wafers in comparison the Si CMOS? We are not told. I think they were happy they have achieved significant stride at all – no matter what the cost. Optimizing processes would be done later, and later means: It takes time. However, they could be doing so while we speak.

Still, as far as we know POET is much closer to practical deployment, to say the least.

Pure speculation, of course.

Andrea