The Janes Group Webpage

                                           What makes it a technology?

In my opinion, nanotechnology represents the convergence of several technologies, which collectively provide the capabilities to build, characterize and assemble structures at the nanometer scale (See figure below).

1) The first technology involves chemical and biological assemblies, e.g. molecules.  Chemists have know for many years how to synthesize molecules and determine their composition and structure.  Simple molecules such as sugar, caffeine and aspirin are nano-scale "things". Biologists and medical researchers now understand molecular-level events that are responsible for many biological processes.  It is now possible to "self-assemble" structures of reasonable complexity using chemical affinities or selective DNA recognition.

2) The second technology involves the ability to image and manipulate matter at the atomic/molecular scale.  Breakthroughs such a scanning probe microscopes provide the ability to actually image atoms on surfaces.  Using such techniques, scientists and engineers have studied the electrical, mechanical, structural and heat-transfer properties of structures at the nanometer scale (and, in some cases, the properties of individual atoms).

3) The third technology is the micro/nano fabrication processing used by the semiconductor industry to create integrated circuits for computers, cell phones, memory, etc.  The primary factor that allows continuous improvements in speed, cost and size is the relentless downscaling of the minimum feature sizes of the transistor (the basic building block of an integrated circuit).  We have now reached the point where the minimum feature size of a MOSFET transistor is below 100 nanometers, and the gate oxide thickness in these devices is below 5 nanometers.  In a very real sense, the chips in the computer you are currently using represent a form of nanotechnology.  The lithographic processes (comparable to transferring a picture from a negative to a paper print) allow literally billions of transistors to be formed on a silicon wafer: quickly, cheaply and very uniformly. These capabilities provide a platform on which we can build interesting structures in a variety of areas.

What is it good for?

Some of you may recall President Clinton's last State of the Union address, where he announced the National Nanotechnology Initiative.  His speech talked of nano-robots that could run through your blood stream and monitor/fix medical conditions.  This may eventually happen, but is probably a long way off.  In the short term, I think that nanotechnology will be incorporated into existing products in a relatively transparent way.  One early application will be in new materials.  Think of what happened when the materials used for tennis rackets and golf clubs changed from wood to steel, then to carbon composite.  The result was lighter, more powerful equipment.  My friends in chemical engineering point out that automobile tires already are made with nanoscale bits of carbon (carbon black) incorporated into the rubber. While carbon black is not controlled with the precision of the type typically described in nanotechnology, it does make your tires perform better. 

Nanotechnology can also play a significant role in the near future in the areas of medicine and environmental sensing.  As mentioned earlier, the molecular scale processes that lead to normal metabolic functions, and to various medical conditions, are now known.  Nanostructured elements may allow us to selectively find and destroy cancer cells, toxins, etc.   Since molecules interact very specifically with other molecules, it should be possible to develop novel gas sensors by connecting a molecular-level event to an external circuit.  My group is currently involved in developing chemical sensors based on these ideas. As I mentioned earlier, silicon microelectronics is already a nano-scale technology.  I think that other nano-structured elements will be added to the microelectronic "toolbox" in the relatively near future -- the expanded capabilities may include optical devices for displays or interconnects, high density memories and biologically-inspired circuits.

I hope this has been informative.  As always, the opinions expressed here are my own and do not represent any official proclamations.

Notes by D. B. Janes, last updated May 2002.  I have borrowed liberally from ideas gathered from discussions with collaborators, as well as presentations on the National Nanotechnology Initiative.