Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Mechanical devices stamped on plastic

To test a new technique for creating micromachines, MIT researchers deposited films of gold on a sheet of plastic; grooves in the plastic are visible as a series of horizontal lines.  Image: Corinne Packard and Apoorva Murarka
To test a new technique for creating micromachines, MIT researchers deposited films of gold on a sheet of plastic; grooves in the plastic are visible as a series of horizontal lines. Image: Corinne Packard and Apoorva Murarka

Abstract:
Microelectromechanical devices gave us the Wii and the digital movie projector. MIT researchers have found a new way to make them.

By Larry Hardesty, MIT News Office

Mechanical devices stamped on plastic

Cambridge, MA | Posted on March 1st, 2010

Microelectromechanical devices — tiny machines with moving parts — are everywhere these days: they monitor air pressure in car tires, register the gestures of video game players, and reflect light onto screens in movie theaters. But they're manufactured the same way computer chips are, in facilities that can cost billions of dollars, and their rigidity makes them hard to wrap around curved surfaces.

MIT researchers have discovered a way to make microelectromechanical devices, or MEMS, by stamping them onto a plastic film. That should significantly reduce their cost, but it also opens up the possibility of large sheets of sensors that could, say, cover the wings of an airplane to gauge their structural integrity. The printed MEMS are also flexible, so they could be used to make sensors with irregular shapes. And since the stamping process dispenses with the harsh chemicals and high temperatures ordinarily required for the fabrication of MEMS, it could allow MEMS to incorporate a wider range of materials.

Conventional MEMS are built through a process called photolithography, in which different layers of material are chemically deposited on a substrate — usually a wafer of some semiconducting material — and etched away to form functional patterns. Since a wafer is at most 12 inches across, arranging today's MEMS into large arrays requires cutting them out and bonding them to some other surface.

Instead of using a wafer, the MIT researchers begin with a grooved sheet of a rubbery plastic, which is coated with the electrically conductive material indium tin oxide. The researchers use what they call a "transfer pad" to press a thin film of metal against the grooved plastic. Between the metal film and the pad is a layer of organic molecules that weaken the metal's adhesion to the pad. If the researchers pull the pad away fast enough, the metal remains stuck to the plastic.

"It's kind of similar to if you have Scotch tape on a piece of paper," says Corinne Packard, a postdoc in the Research Lab of Electronics at MIT who led the work, along with professors of electrical engineering Vladimir Bulović and Martin Schmidt. "If you peel it off slowly, you can delaminate the tape very easily. But if you peel fast, you'll rip the paper."

Once the transfer pad has been ripped away, the metal film is left spanning the grooves in the plastic like a bridge across a series of ravines. Applying a voltage between the indium-tin-oxide coating and the film can cause it to bend downward, into the groove in the plastic: the film becomes an "actuator" — the moving part in a MEMS. Varying the voltage would cause the film to vibrate, like the diaphragm of a loudspeaker; selectively bending different parts of the film would cause them to reflect light in different ways; and dramatically bending the film could turn a smooth surface into a rough one. Similarly, if pressure is applied to the metal film, it will generate an electric signal that the researchers can detect. The film is so thin that it should be able to register the pressure of sound waves.

Serendipity

The discovery of the manufacturing technique, which the MIT team describes in a forthcoming issue of the journal Advanced Materials, was a happy accident. The researchers were actually trying to use a printing technique to build an electrical circuit. They had created a plastic stamp with a pattern molded into it and were trying to transfer that pattern to a thin sliver film. They had expected that the plastic would pull away the silver it made contact with, leaving behind an electrode that could control an organic light-emitting diode.

Instead, however, the stamp kept pulling away the entire silver film. "The first couple times we did this, we were like, ‘Ah! Bummer, man,'" says Bulović. "And then a light bulb went off, and we said, ‘Well, but we just made the world's first printed MEM.'" The stamp was intended as a means of creating an electronic device; instead, it ended up serving as the basis for a device itself. The researchers' ensuing work was on the ideal architecture for the device and on ways to minimize the metal film's adhesion to the transfer pad and maximize its adhesion to the grooved plastic.

Because the researchers hadn't set out to make MEMS, and because, to their knowledge, their films constitute the first stamped MEMS devices, they're still trying to determine the ideal application of the technology. Sheets of sensors to gauge the structural integrity of aircraft and bridges are one possibility; but the MEMS could also change the physical texture of the surfaces they're applied to, altering the airflow over a wing, or modifying the reflective properties of a building's walls or windows. A sheet of thousands of tiny microphones could determine, from the difference in the time at which sound waves arrive at different points, where a particular sound originated. Such a system could filter out extraneous sounds in a noisy room, or even perform echolocation, the way bats do. The same type of sheet could constitute a paper-thin loudspeaker; the vibrations of different MEMS might even be designed to interfere with each other, so that transmitted sounds would be perfectly audible at some location but inaudible a few feet away. The technology could also lead to large digital displays that could be rolled up when not in use.

John Rogers, a researcher at the University of Illinois at Urbana-Champaign who has pioneered techniques for printable electrical circuits, is particularly intrigued by the idea that printable MEMS could incorporate materials that are incompatible with existing MEMS manufacturing processes. "The ability to do heterogeneous integration of different material types into micromachines is a neat capability that would be enabled by this form of manufacturing," Rogers says. "It opens up new design opportunities because it relaxes constraints on choices of materials." And in general, Rogers says, the idea of printing MEMS is "cool." "What they've done in this paper is demonstrated, for the first time, to my knowledge, this kind of concept."

####

About MIT
The mission of MIT is to advance knowledge and educate students in science, technology and other areas of scholarship that will best serve the nation and the world in the 21st century — whether the focus is cancer, energy, economics or literature.

For more information, please click here

Contacts:
Larry Hardesty
Writer (computer science and technology)
617-253-4735

Copyright © MIT

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

News and information

Starpharma initiates new DEP™ drug delivery program with AstraZeneca July 27th, 2016

Ageing can drive progress: Population ageing is likely to boost medicine, nanotechnology and robotics, but increase political risks July 27th, 2016

WSU researchers 'watch' crystal structure change in real time: Breakthrough made possible by new Argonne facility July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

Thin films

Cambridge Advanced Imaging Centre praises support film consistency and quality from EM Resolutions July 5th, 2016

Novel capping strategy improves stability of perovskite nanocrystals: Study addresses instability issues with organometal-halide perovskites, a promising class of materials for solar cells, LEDs, and other applications June 13th, 2016

New nanomaterial offers promise in bendable, wearable electronic devices: Electroplated polymer makes transparent, highly conductive, ultrathin film June 13th, 2016

Perovskite solar cells surpass 20 percent efficiency: EPFL researchers are pushing the limits of perovskite solar cell performance by exploring the best way to grow these crystals June 13th, 2016

Possible Futures

Ageing can drive progress: Population ageing is likely to boost medicine, nanotechnology and robotics, but increase political risks July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

New lithium-oxygen battery greatly improves energy efficiency, longevity: New chemistry could overcome key drawbacks of lithium-air batteries July 26th, 2016

Academic/Education

The NanoWizard® AFM from JPK is applied for interdisciplinary research at the University of South Australia for applications including smart wound healing and how plants can protect themselves from toxins July 26th, 2016

News from Quorum: The College of New Jersey use the Quorum Cryo-SEM preparation system in a project to study ice crystals in high altitude clouds July 19th, 2016

Leti and Korea Institute of Science and Technology to Explore Collaboration on Advanced Technologies for Digital Era July 14th, 2016

SUNY Poly Celebrates Its 10th Year Exhibiting at SEMICON West with Cutting Edge Developments in Integrated Photonics and Power Electronics July 8th, 2016

MEMS

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

New research unveils graphene 'moth eyes' to power future smart technologies: New ultra-thin, patterned graphene sheets will be essential in designing future technologies such as 'smart wallpaper' and Internet-of-things applications March 1st, 2016

Vesper Collaborates with GLOBALFOUNDRIES to Deliver First Piezoelectric MEMS Microphones: Acoustic sensing company works with top foundry to support mass-market consumer products January 21st, 2016

MEMS & Sensors Industry Group Previews “Internet of MEMS & Sensors” at CES 2016 -- Global industry association invites CE OEMS/integrators to conference track on January 7 January 6th, 2016

Sensors

Ultrasensitive sensor using N-doped graphene July 26th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Electron 'spin control' of levitated nanodiamonds could bring advances in sensors, quantum information processing July 20th, 2016

Easier, faster, cheaper: A full-filling approach to making nanotubes of consistent quality: Approach opens a straightforward route for engineering the properties of single-wall carbon nanotubes July 19th, 2016

Discoveries

WSU researchers 'watch' crystal structure change in real time: Breakthrough made possible by new Argonne facility July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

New nontoxic process promises larger ultrathin sheets of 2-D nanomaterials July 27th, 2016

Ultrasensitive sensor using N-doped graphene July 26th, 2016

Announcements

Starpharma initiates new DEP™ drug delivery program with AstraZeneca July 27th, 2016

Ageing can drive progress: Population ageing is likely to boost medicine, nanotechnology and robotics, but increase political risks July 27th, 2016

WSU researchers 'watch' crystal structure change in real time: Breakthrough made possible by new Argonne facility July 27th, 2016

Enhancing molecular imaging with light: New technology platform increases spectroscopic resolution by 4 fold July 27th, 2016

Aerospace/Space

Scientists move 1 step closer to creating an invisibility cloak July 15th, 2016

Bouncing droplets remove contaminants like pogo jumpers: Researchers at Duke University and the University of British Columbia are exploring whether surfaces can shed dirt without being subjected to fragile coatings July 7th, 2016

Russian physicists create a high-precision 'quantum ruler': Physicists have devised a method for creating a special quantum entangled state June 25th, 2016

Novel capping strategy improves stability of perovskite nanocrystals: Study addresses instability issues with organometal-halide perovskites, a promising class of materials for solar cells, LEDs, and other applications June 13th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic