October 12, 2004

"Nanotechnology: Fact and Fantasy"

A Multidisciplinary Panel
Led by

R. Fabian W. Pease, Ph. D. 

William Ayer Professor
of Electrical Engineering at Stanford University

 Keongjae Cho, Professor of Mechanical Engineering
Kenneth Goodson, Professor Mechanical Engineering
Philip Wong, Professor of Electrical Engineering,
Thomas Kenny, Professor of Mechanical Engineering

From left to right, Nancy Peterson, Roche Palo Alto, and Professors Philip Wong, Kenneth Goodson, Keongjae Cho, Fabian Pease and  Thomas Kenny.

Dr. Fabian Pease chaired the panel and framed the discussion by the following questions:

  • What is nanotechnology?

A broad field, defined by Pease as any man-made structure smaller than 100 nanometers (100 millionth of a millimeter) i.e. 700 times smaller than a blood cell of 70 micron and 3,333 times smaller than a particle of sand of 0.33 millimeter.  Microscopic size itself is not the goal.  Rather, materials behave very differently at this scale and these behaviors, although difficult to control, are the promise that nanotechnology offers.

  • What is nanotechnology good for?

In this “over-hyped” field, applications such as the space elevator, made of carbon nanotubes, appear far-fetched; the maximum height built to date with this material is less than two inches, one member of the audience volunteered. The development of motors has been abandoned: flexures are more efficient moving parts, so don't expect to see nano-helicopters.  Prof. Kenny believes that successful commercial applications will sneak-up on us and that we should be wary of what comes with a nanotech banner. Besides the current state-of-the-art in semiconductor technology, few applications are commercially viable today: the Gore-Tex® fabric with its 10 nanometer holes is the only example cited.  Prof. Wong spoke of nano-refrigerators pumping fluids, of thermal velcro made of nano-tubes in order to dissipate the enormous concentrations of heat that now plague semiconductor chips in a 10 x 30 nm area, and of thermo-electric devices whose efficiency is starting to approach that of current heat sinks plus fans.

All panelists were hesitant when asked to venture a date for commercialization: 5-10 years from now at the earliest, 15-20 years for medical applications. According to Kenney, delivery systems in bio-medicine seem the most promising, given medicine’s existing involvement with molecules of comparable sizes.  Biological computing however seems unlikely: biological processes decay and do not withstand high temperatures.

When panelists were invited to address questions to each other, Fabian Pease asked Tom Kenney whether nanotech propulsion would mimic flapping insects or propeller engines.  Kenney predicted that insect flight would win, if power sources rivaling that of the insects can also be developed.  Tom Kenny asked Keongjae Cho about quantum computation.  Cho said that cryptograpgy is the only area in which quantum computation is already demonstrated.  Some 15-20 people are working on it at IBM. 

Nanotechnology research is conducted at the new interdisciplinary Clark Center at Stanford.  To accommodate multi-disciplinary projects the labs are furnished with movable fixtures and thus quickly reconfigurable. For tours of the center, visit http://biox.stanford.edu/news/tours.html or send an email to: fsincock@stanford.edu.

Prof. Pease suggested the following links:

There's Plenty of Room at the Bottom, by Richard P. Feynman
National Nanotechnology Initiative

Many thanks to Marc Pasturel for these notes (marc@soleil.com)