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[Reno]

SAN JOSE, Calif., April 22 (UPI) -- IBM scientists announced creation of breakthrough nanotechnology that can create tiny patterns and structures at greatly reduced cost and complexity.

To demonstrate the new microscopic technique, IBM researchers said they created a 3D map of the Earth that's so tiny that 1,000 of them could fit on one grain of salt. The technique uses a silicon tip with a sharp apex 100,000 times smaller than a sharpened pencil and similar to the kind used in atomic force microscopes.

"The tip is attached to a bendable cantilever that controllably scans the surface of the substrate material with the accuracy of one nanometer," IBM said. "By applying heat and force, the nano-sized tip can remove substrate material based on predefined patterns, thus operating like a 'nanomilling' machine with ultra-high precision."

IBM said the new patterning technique can be used to develop nano-sized objects in fields such as electronics, chip technology, medicine, life sciences and opto-electronics, with resolutions of 15 nanometers and possibly smaller.

The equipment can fit on a tabletop, researchers said, and operate at improved and extended capabilities compared with e-beam lithography, and at about one-tenth the cost.

The breakthrough is described in two online papers -- one on the Science Express Web site and in the other in the before-print edition of the journal Advanced Materials.

source

[Elus]

This is quite fascinating. When I did some work at the University of Pennsylvania, I learned that there are two games in town when it comes to building nanotechnology devices:

• Bottom-up: Adding atoms or molecules to a substrate, and thus building the structure from the bottom-up.
• Top-down: Subtracting atom or molecules from a preexisting substrate.

The approach described in your article involves top-down assembly. Unfortunately, top down assembly has limitations which bottom-up assembly doesn't have, but it's still an exciting breakthrough nonetheless.

I'm curious as to how exactly the heat is generated at the end of the silicon tip, such as when they said, "By applying heat and force, the nano-sized tip can remove substrate material." Is silicon even conductive enough to allow a heat transfer? Perhaps silicon doesn't melt as easily on the nanoscale, or perhaps much less heat is required to achieve the milling effect.

Very interesting stuff.

Here's a picture of AFM for reference:



Source: http://www.nanotech-...lery/AS-AFM.jpg

Edited by Elus Efelier, 24 April 2010 - 04:55 AM.