Dip-Pen Nanolithography

Dip Pen Nanolithography (DPN) is a scanning probe lithography technique where an atomic force microscope tip is used to transfer molecules to a surface via a solvent meniscus. This technique allows surface patterning on scales of under 100 nanometres. DPN is the nanotechnology analog of the dip pen (also called the quill pen), where the tip of an atomic force microscope cantilever acts as a "pen," which is coated with a chemical compound or mixture acting as an "ink," and put in contact with a substrate, the "paper."

DPN enables direct deposition of nanoscale materials onto a substrate in a flexible manner. The vehicle for deposition can include pyramidal scanning probe microscope tips, hollow tips, and even tips on thermally actuated cantilevers. Recent advances have demonstrated massively parallel patterning using two-dimensional arrays of 55,000 tips, depicted below. Applications of this technology currently range through chemistry, materials science, and the life sciences, and include such work as ultra high density biological nanoarrays, additive photomask repair, and brand protection for pharmaceuticals.

The transfer of a molecular 'ink' from a coated AFM tip to a substrate was first reported by Jaschke and Butt in 1995. The technique was further developed by a research group at Northwestern University led by Chad Mirkin [http://www.chem.northwestern.edu/~mkngrp/dpn.htm] who also introduced the term "DPN". The company NanoInk, Inc. holds a patent on Dip Pen Nanolithography, and "DPN" and "Dip Pen Nanolithography" are trademarks or registered trademarks of NanoInk.

References

*Jaschke M.; Butt, H.-J. "Deposition of Organic Material by the Tip of a Scanning Force Microscope" Langmuir, 1995, 11, 1061-1064.
*Piner, R. D.; Zhu, J.; Xu, F.; Hong, S.; Mirkin, C. A. "Dip Pen Nanolithography," Science, 1999, 283, 661-663.
*Science, 2002, 295, 1702-1705 DOI: 10.1126/science.1067172
* [http://www.chem.northwestern.edu/~mkngrp/dpn.htm Dip Pen Nanolithography subgroup] at Northwestern University

See also

* Nanolithography
* Scanning probe lithography
* Atomic force microscope
* [http://www.nanoink.net/WhatisDPN.htm NanoInk DPN]
* [http://www.nanodaddy.com DPN Research News]
* [http://dpnforum.com/phpBB3/index.php dpnforum] , a public discussion board and Dip Pen Nanolithography resource