Thursday, February 01, 2007

Who says you need a replicating assembler?

I've been studying a host of the bottom up self-assembly approaches and I'm becoming quite impressed. The one linked above has me imagining a roll-to-roll self assembly regime which could manufacture literally tons of assorted nanomaterials at low prices without the need for self replicating molecular nanoassemblers. Sure it wouldn't fit on a desktop but for mass production needs it'd work great. Especially when you add in the developments in molecular imprint lithography, dip pen lithography and imprint lithography. I can picture this channel of methods rolling out little tabs of medicines, micro circuitry, sensors, you name it, even those little breath mint sheets only made nano better.

Labels: , ,

Link

Friday, January 05, 2007

Nanotech milepost

As we go into 2007 I’ve been wondering exactly where in the curve of nanotech evolution we are at. 2006 saw many advances which were surprising if not unexpected.

From the top down we are approaching the 35 nanometer node. Lots and lots of sub-90 nanometer stuff has been going on for a while but immersion lithography and extreme ultra-violet have pushed us well below the 45 nanometer regime in actual product-to-market.

While we’re on the subject of lithography we’ll touch on several related areas which have been maturing nicely. Four arenas of lithography are rapidly dropping well below the limits of standard optical lithography. The one that seems most likely to be rapidly adopted by industry is nanoimprint lithography, so called “squish and flash” that currently operates in the 10-20 nanometer region. Next is dip-pen nanolithography which operates at and below 10 nanometers and has been especially well received by biotechnology interests. DPN went massively parallel in 2006 with STM heads featuring hundreds of needles. Self-assembly techniques using diblock copolymers and molecular imprint lithography round out this set as providing methods which span the last few nanometers down into the sub-nanometer region of molecules themselves.

From the bottom-up a whole host of scientific advances have been showing themselves off. Rice’s nanocar stands out as a stirling example. Built entirely by chemical methods the nanocar has joined a veritable army of nanomachinery. Nanobelts of zinc-oxide, carbon nanotubes, fullerenes and structured carbons of almost every conceivable shape, structured DNA complexes, rotoxanes, quantum dots and of course the entire encyclopedia of small molecules are all well understood entities of the sub-nanometer realm.

The ubiquitous scanning tunneling electron microscope has been advanced with needles tipped by functionalized carbon nanotubes. Proof-of-concept mechanosynthesis has been demonstrated albeit without any sort of bulk application.

The necessary understanding of underlying quantum mechanical behavior such as phonons, plasmons, evanescent waves, near field optical affects and a plethora of other phenomenological studies round out the scientific advances made in 2006.

It doesn’t take a lot of imagination to picture devices rationally designed from this rather complete toolbox.

Labels: , , , , , ,