IBM and the Nanotube Transistor

At a conference a couple of years ago, I got into an argument with Chris Phoenix of the Center for Responsible Nanotechnology, not a hard thing to do since Chris lives to argue. The Center is mainly concerned with molecular manufacturing, which they seem to believe is the only true manifestation of nanotech despite the fact that it is mainly speculative fiction to this point. Chris was concerned that India or China could develop a molecular manufacturing capability and that the West would immediately be swamped because we could never catch up. I offered the opinion that there was more nanotech expertise in the Zurich lab of IBM than there was in all of India so I wasn’t overly concerned.

We should probably get over our chauvinistic leanings, one way or another. Ever since the outlines of the nanotech revolution became apparent, it has been argued that the real winners would not be the smattering of entrepreneur driven enterprises but the big multinationals like IBM, GE or Dow Chemical. The GE plant which employs my wife is closing next summer, to be replaced by a similar plant operated in China. These multinationals do not really care about the nation-state from which their earnings derive. In fact, their revenues are greater than the gross national product of most countries.

Just the round-off error is IBM’s revenues would dwarf the current nanotech industry. IBM would never be mistaken by stock market pros for a nanotech play, but nanotech owes much of the seriousness with which it is taken to IBM. In a sense, the nanotech era was launched by the invention of the scanning tunneling microscope by Gerd Binnig and Heinrich Roher from the IBM Zurich Research Laboratory. Don Eigler used it, not only as an imaging tool, but to move individual atoms around. His first masterpiece, titled “The Beginning” in IBM’s Almaden Lab Gallery, spelled out the IBM logo in xenon atoms. The ability to manipulate matter at the atomic level was for the first time proven.

Still, IBM did not bother commercialize the scanning tunneling microscope or Binnig’s later innovation, the atomic force microscope, by itself. Big Blue was content to license that out to others (Veeco holds the major market share for scanning probe microscopes). IBM is waiting for a market worth its attention. Like transistors…

IBM has now created the first carbon nanotube electroluminescent transistor, which it claims, according to EE Times, glows 1,000 times brighter than a light-emitting diode with as much as 10,000 times more photon flux. Because it creates thousands of photons in silicon at the same energy expenditure as a single photon in gallium arsenide, IBM predicts that carbon nanotube transistors will lead to integrated optics on silicon chips. That is, information will be shuttled around using photons instead of electrons, light instead of electricity.

Though other groups have shown previously that nanotubes were luminescent after being stimulated with lasers, IBM is the first to show luminescence in response to purely electrical stimulation. It does so by suspending the nanotubes no more than 2 nm in diameter over a silicon back gate. The devices emit infrared light that is related exponentially to the drive current of the back gate.

Is this the anticipated killer app for nanotechnology? Possibly, but computer chips are hardly my specialty. I would appreciate any comments by knowledgeable adults or precocious children. E-mail me at steven.alan.edwards@gmail.com.