Nano-Pen Writes in Tiny Letters

University of Arkansas researchers use a newly developed nano-manufacturing technique called Electronic Pen Lithography (EPS) to etch the letters "NSF" into a gold sheet. Each hole is only 10 nanometers in diameter; one nanometer is one billionth of a meter.

NSF stands for National Science Foundation, the federal agency that funded the research.

EPL uses a sharpened tip the size of a single atom to apply an electric charge through a thin film of oil molecules onto a target surface. Researchers think the long chain-like oil molecules are acting like "nano-wires" connecting the tool-tip and the target surface.

The tiny tip is attached to the end of a scanning electron microscope, allowing researchers to immediately see what they've done, something that is not always possible with other techniques. There is also no need for vacuum chambers like other techniques, and EPL is relatively inexpensive and offers tighter control.

Researchers speculate that EPL could be used to create nanopores that can detect DNA, nanoscale bridges for use in electronic devices, molecular sieves for protein sorting and nanojets for fuel or drug delivery.

--Ker Than

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Credit:  Ajay Malshe, University of Arkansas