The first practical fountain pen was invented in 1884 by Lewis Waterman. Although pens with self-contained ink reservoirs had existed for more than a hundred years before his invention, they suffered from ink leaks and other troubles. Waterman solved these problems by inventing the capillary feed which produced even ink flow. Now fountain pen history is repeating itself in the tiny world of nanoscale writing.
Researchers at Northwestern University have demonstrated writing at the sub-100 nanometer molecular scale in fountain-pen fashion. They developed a novel atomic force microscope (AFM) probe chip with an integrated microfluidic system for capillary feeding of molecular ink.
Their results are published online by Small, a new journal dedicated to breakthroughs in nanoscience and engineering (
http://dx.doi.org/10.1002/smll.200500027).
Dip-pen nanolithography (DPN) has been well-known for its capability of high-resolution direct writing as a bottom-up nanofabrication technique. The DPN technique exploits controlled deposition of molecules from an AFM tip to a surface. However, the need of replenishing ink whenever exhausted has been a limiting feature. Various attempts have been reported to overcome such a drawback, but none of them reached molecular patterns with features smaller than 100 nanometers.
The Nanofountain Probe (NFP) developed by Horacio D. Espinosa, professor of mechanical engineering, and his colleagues employs a volcano-like dispensing tip and capillary fed solutions to enable sub-100 nanometer molecular writing. The NFP was microfabricated on a chip to be mounted on commercially available AFMs. The device consists of an on-chip reservoir, microchannels and a volcano-like dispensing tip. The microchannels are embedded in the AFM cantilevers of the chip and the volcano dispensing tip has an annular aperture to guide ink dispensing. The ink on the reservoir is driven through the microchannel via capillary action to reach the dispensing tip. At present, the smallest feature width achieved with the device is 40 nanometers.
The standard microfabrication techniques used for the NFP chip -- an important feature of this development -- provides scalability to massively parallel arrays of probes and reservoirs for high throughput patterning with multiple molecular inks.
"The writing capability of such NFP arrays with chemical and bimolecular inks in fountain-pen mode is unique," said Espinosa. "We believe the technology will likely lead to many high-impact applications in the field of nanosensors, biotechnology and pharmaceuticals."
In addition to Espinosa, other authors on the Small paper are graduate student Keun-Ho Kim and research assistant professor of mechanical engineering Nicolaie A. Moldovan, both from Northwestern.
Source: Northwestern University
Related stories:
U of T home to first molecular printer in Canada
Think of it as a miniscule dot-matrix printer that uses biological ink. Students and faculty at the University of Toronto’s Institute for Optical Sciences (IOS) will have access to the Nano eNabler, the first benchtop molecular printer in Canada, which will allow them to place microscopic dots of biological material onto surfaces with nanometer spatial precision.
IBM Researchers Demonstrate New Method for Rapid Molecule Sorting and Delivery
IBM researchers have demonstrated a new nanoscale method that both rapidly separates very small numbers of molecules and also delivers them precisely onto surfaces with unprecedented control. When fully developed, the new technique has the potential to improve such diverse applications as medical lab tests and future nanoelectronic circuit manufacturing.
Two-Tone Molecular Printing
Nanopipette with two chambers produces microstructures made of biomolecules.
The emblem of the Cambridge University, a portrait of scientist Isaac Newton, rendered in microscale as a colorful, fluorescing image: are British researchers just playing around? No, it’s a "finger exercise" for serious science. For modern, miniaturized analytical and diagnostic processes, it is necessary to attach microstructures made of different biomolecules to tiny supports with high precision.
Writing at the Nanoscale: 'Electro Pen' may impact a host of developing nanotechnologies
At the U.S. Department of Energy's Brookhaven National Laboratory, scientists have developed a new chemical "writing" technique that can create lines of "ink" only a few tens of nanometers, or billionths of a meter, in width.
Bottoms up: Better organic semiconductors for printable electronics
Researchers from the National Institute of Standards and Technology and Seoul National University have learned how to tweak a new class of polymer-based semiconductors to better control the location and alignment of the components of the blend. Their recent results—how to move the top to the bottom—could enable the design of practical, large-scale manufacturing techniques for a wide range of printable, flexible electronic displays and other devices.
Northwestern chemists take gold, mass-produce Beijing Olympic logo
Northwestern University nanoscientist Chad A. Mirkin has mass-produced the 2008 Summer Olympics logo -- 15,000 times. All the logos take up only one square centimeter of space.
Fingerprints provide clues to more than just identity
Fingerprints can reveal critical evidence, as well as an identity, with the use of a new technology developed at Purdue University that detects trace amounts of explosives, drugs or other materials left behind in the prints.
Finding out what the Big Bang and ink jets have in common
It often turns out there is more to commonplace everyday events than meets the eye. The folding of paper, or fall of water droplets from a tap, are two such events, both of which involve the creation of singularities requiring sophisticated mathematical techniques to describe, analyse and predict. On the positive side, there is much in common between many such singular events across the whole range of scales, from microscopic interactions to the very formation of the universe itself during the Big Bang.