Nanotechnology Printer On The Horizon
Desktop printers are advancing in revolutionary ways, from 3-D
printers that could in principle help manufacture robots at home to
cell-placing biotechnological machines that researchers hope could one
day fabricate organs on demand. Now scientists are developing a desktop
system to create nanosized devices whose parts are just molecules in
size, potentially unshackling such inventions from the
multibillion-dollar foundries currently required to make them.
Working at scales on the order of billionths of a meter could lead to circuitry far more powerful than modern electronics, as well as devices that incorporate biomolecules to, for instance, analyze genes.
Decentralizing nanosciences
Currently, most nanofabrication is carried out in multibillion-dollar foundries, but researchers have long sought to create a desktop tool that decreases manufacturing time and cost.
"The key idea here is best explained by analogy to printed documents," says Chad Mirkin, director of Northwestern University’s International Institute for Nanotechnology in Evanston, Ill. “Many documents, books, newspapers and the like are printed in centralized facilities. Consider how the desktop printer changed information transfer by allowing one to rapidly generate documents as needed and at the point of use. Our work is designed to take nanofabrication out of the foundry and on to the desktop."
Mirkin and his colleagues have invented a system slightly larger than a printer that can produce working electronic circuits. His lab even used it to produce a map of the world with nanoscale resolution that is large enough to see with the naked eye.
"This methodology could lead to true desktop nanofabrication, a longstanding goal in the nanoscience community," Mirkin says.
Building with light beams
The secret of the machine lies in beams of light. A single stream of ultraviolet light is directed at microscopic mirrors that break it up into thousands of individual rays. These are in turn aimed into an array of pyramids, each covered in a layer of gold.
The pyramids are each 30 microns wide and 20 microns tall — in comparison, the average human hair is 100 microns wide. They essentially behave as funnels, with light emerging from 100-nanometer-wide apertures at their tips in precise beams.
These shafts of light are directed at surfaces covered in light-sensitive materials called resists that are chemically altered by the light. In this way, each beam essentially acts like a pen, earning the technique its name, beam pen lithography.
(Schematic showing the operation of the desktop nanofabrication system with digital micromirrors either directing light at or away from individual pyramidal pens in a massive array. These pens serve to direct the light to points at their tips. Photo courtesy X. Liao et al.)
The scientists can generate new structures by programming what pattern the pens should draw. The smaller the aperture at each pyramid’s tip, the tinier the resulting feature.
"There are no other desktop nanofabrication systems that can match the capabilities of this instrument," Mirkin says. “There are many other nanofabrication techniques, but all fall short when simultaneously compared against the throughput, resolution and cost of actuated beam pen lithography. For example, one competing nanofabrication technique is electron beam lithography, which has excellent spatial resolution, but requires a million-dollar instrument and has lower throughput than actuated beam pen lithography on account of relying on a single beam while our system utilizes thousands of parallel beams."
In a typical experiment, the system can generate roughly 5,000 features per second. “This means that depending on the desired resolution, centimeter-scale images can be written in a matter of minutes to hours," Mirkin says.
Since the materials used to make the desktop system are readily accessible, commercialization may be as little as two years away, said he says. The desktop system might ultimately cost $300,000 or less on the market, “but this is just a projection.”
The scientists detailed their findings July 19 in the journal Nature Communications.
Top Image: Nanotechnology via Shutterstock.
Charles Q. Choi has
written for Scientific American, The New York Times, Wired, Science and
Nature, among others. In his spare time, he has traveled to all seven
continents, including scaling the side of an iceberg in Antarctica,
investigating mummies from Siberia, snorkeling in the Galapagos,
climbing Mt. Kilimanjaro, camping in the Outback, avoiding thieves near
Shaolin Temple and hunting for mammoth DNA in Yukon.
Working at scales on the order of billionths of a meter could lead to circuitry far more powerful than modern electronics, as well as devices that incorporate biomolecules to, for instance, analyze genes.
Decentralizing nanosciences
Currently, most nanofabrication is carried out in multibillion-dollar foundries, but researchers have long sought to create a desktop tool that decreases manufacturing time and cost.
"The key idea here is best explained by analogy to printed documents," says Chad Mirkin, director of Northwestern University’s International Institute for Nanotechnology in Evanston, Ill. “Many documents, books, newspapers and the like are printed in centralized facilities. Consider how the desktop printer changed information transfer by allowing one to rapidly generate documents as needed and at the point of use. Our work is designed to take nanofabrication out of the foundry and on to the desktop."
Mirkin and his colleagues have invented a system slightly larger than a printer that can produce working electronic circuits. His lab even used it to produce a map of the world with nanoscale resolution that is large enough to see with the naked eye.
"This methodology could lead to true desktop nanofabrication, a longstanding goal in the nanoscience community," Mirkin says.
Building with light beams
The secret of the machine lies in beams of light. A single stream of ultraviolet light is directed at microscopic mirrors that break it up into thousands of individual rays. These are in turn aimed into an array of pyramids, each covered in a layer of gold.
The pyramids are each 30 microns wide and 20 microns tall — in comparison, the average human hair is 100 microns wide. They essentially behave as funnels, with light emerging from 100-nanometer-wide apertures at their tips in precise beams.
These shafts of light are directed at surfaces covered in light-sensitive materials called resists that are chemically altered by the light. In this way, each beam essentially acts like a pen, earning the technique its name, beam pen lithography.
(Schematic showing the operation of the desktop nanofabrication system with digital micromirrors either directing light at or away from individual pyramidal pens in a massive array. These pens serve to direct the light to points at their tips. Photo courtesy X. Liao et al.)
The scientists can generate new structures by programming what pattern the pens should draw. The smaller the aperture at each pyramid’s tip, the tinier the resulting feature.
"There are no other desktop nanofabrication systems that can match the capabilities of this instrument," Mirkin says. “There are many other nanofabrication techniques, but all fall short when simultaneously compared against the throughput, resolution and cost of actuated beam pen lithography. For example, one competing nanofabrication technique is electron beam lithography, which has excellent spatial resolution, but requires a million-dollar instrument and has lower throughput than actuated beam pen lithography on account of relying on a single beam while our system utilizes thousands of parallel beams."
In a typical experiment, the system can generate roughly 5,000 features per second. “This means that depending on the desired resolution, centimeter-scale images can be written in a matter of minutes to hours," Mirkin says.
Since the materials used to make the desktop system are readily accessible, commercialization may be as little as two years away, said he says. The desktop system might ultimately cost $300,000 or less on the market, “but this is just a projection.”
The scientists detailed their findings July 19 in the journal Nature Communications.
Top Image: Nanotechnology via Shutterstock.
Charles Q. Choi has
written for Scientific American, The New York Times, Wired, Science and
Nature, among others. In his spare time, he has traveled to all seven
continents, including scaling the side of an iceberg in Antarctica,
investigating mummies from Siberia, snorkeling in the Galapagos,
climbing Mt. Kilimanjaro, camping in the Outback, avoiding thieves near
Shaolin Temple and hunting for mammoth DNA in Yukon.
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