[annie123 (OP)]

This is  one of the latest devlopments in nanotech. - a transistor probe 1000 smaller than a hair, smaller than a virus, that can go into a single cell and monitor its function.(Charles Lieber - Harvard)
I would like to know from anyone who works in this field how these tiny objects are manufactured - how can anything make something smaller than a virus? I know we can see things smaller, but to actually manipulate them, or make things like a transistor that contains things or has circuits - how is this possible?I can see how something smaller than a virus could grow and make itself, but something mechanical like this has to have something outsisde itself putting it together ??

[Geezer]

You might take a look at E-beam lithography. Here's a link that does a much better job of explaining it that I can.

http://en.wikipedia.org/wiki/Electron_beam_lithography

[annie123 (OP)]

Thanks. very interesting.

[graham.d]

It's way beyond e-beam lithography, Geezer. This is about nanowires and dimensions of the order of 1 nanometre. There is not yet a good or practical lithography method for configuring nanowires into usable electronic circuits. Typically photolith is currently limited (even with ebeam) to around 10 to 20nm. Studies of how to design circuits using nanowires revolve around more biological type techniques of "programming" sequences of movements in thin films. I have not studied this, but the Langmuir-Blodgett techniques for organising thin films is one such method.