Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tiny 'MEMS' devices to filter, amplify electronic signals

12.08.2009
Researchers are developing a new class of tiny mechanical devices containing vibrating, hair-thin structures that could be used to filter electronic signals in cell phones and for other more exotic applications.

Because the devices, called resonators, vibrate in specific patterns, they are able to cancel out signals having certain frequencies and allow others to pass.

The result is a new type of "band-pass" filter, a component commonly used in electronics to permit some signals to pass through a cell phone's circuitry while blocking others, said Jeffrey Rhoads, an assistant professor of mechanical engineering at Purdue University.

Such filters are critical for cell phones and other portable electronics because they allow devices to process signals with minimal interference and maximum transmission efficiency. The new technology represents a potential way to further miniaturize band-pass filters while improving their performance and reducing power use, Rhoads said.

The device is an example of a microelectromechanical system, or a MEMS, which contain tiny moving parts. Incoming signals generate voltage that produces an electrostatic force, causing the MEMS filters to vibrate.

Researchers have proposed linking tiny beams in straight chains, but Rhoads has pursued a different approach, arranging the structures in rings and other shapes, or "non-traditional coupling arrangements." One prototype, which resembles spokes attached to a wheel's hub, is about 160 microns in diameter, or comparable in size to a grain of sand.

Findings are detailed in a research paper to be presented on Sept. 2 during a meeting of the American Society of Mechanical Engineers' Third International Conference on Micro and Nano Systems. The conference runs from Aug. 30 to Sept. 2 in San Diego. The paper was written by Rhoads and mechanical engineering graduate student Venkata Bharadwaj Chivukula.

In addition to their use as future cell phone filters, such resonators also could be used for advanced chemical and biological sensors in medical and homeland-defense applications and possibly for a new type of "mechanical memory element" that harnesses vibration patterns to store information.

"The potential computer-memory application is the most long term and challenging," Rhoads said. "We are talking about the possibility of creating complex behaviors out of relatively simple substructures, similar to how in cellular biology you can have a relatively complex behavior by combining hundreds or thousands of simple cells."

The band-pass filter design promises higher performance than previous MEMS technology because it more sharply defines which frequencies can pass and which are rejected. The new design also might be more robust than the traditional linear arrangement, meaning devices could contain manufacturing flaws and still perform well.

The devices are made of silicon and are manufactured using a "silicon-on-insulator" procedure commonly used in the electronics industry to make computer chips and electronic circuits. The small, vibrating mechanical structures contain beams about 10 microns in diameter, which is roughly one-tenth the width of a human hair. The beams can be connected mechanically, like tiny springs, or they can be linked using electric fields and magnetic attractions.

"We are in the process of making a second prototype," said Rhoads, who has used simulations and also conducted experiments with the devices to demonstrate that the concept works.

The devices are being fabricated at the Birck Nanotechnology Center in Purdue's Discovery Park through a collaboration with Dimitrios Peroulis, an assistant professor of electrical and computer engineering.

The research is based at a new Dynamic Analysis of Micro/Nanosystems Laboratory at Birck. The lab, managed by Rhoads and mechanical engineering professor Arvind Raman, is equipped with an instrument called a scanning laser Doppler vibrometer, which uses a laser to measure the minute movement of the tiniest structures. The system is housed inside a vacuum chamber sitting on top of a special vibration-absorbing platform critical to making the precise measurements.

Other faculty members and graduate students also use the specialized facility.

The research is funded by the National Science Foundation through an NSF Faculty Early Career Development grant, awarded to outstanding young researchers. So far four Purdue researchers have received the grants this year. The research includes educational components using Purdue's nanoHUB - the Web portal of the Network for Computational Nanotechnology, also NSF-funded and based at Purdue - as well as Purdue's Summer Undergraduate Research Fellowship program.

Rhoads will develop and deploy on the nanoHUB a software tool to simulate the behavior of the resonators, a new K-12 education curriculum on emerging microelectromechanical and nanoelectromechanical systems, and college-level course materials and lectures associated with a new course on the systems.

Writer: Emil Venere, 765-494-4709, venere@purdue.edu
Source: Jeffrey Rhoads, 765-494-5630, jfrhoads@purdue.edu

Emil Venere | EurekAlert!
Further information:
http://www.purdue.edu

More articles from Power and Electrical Engineering:

nachricht Open, flexible assembly platform for optical systems
24.01.2017 | Fraunhofer-Institut für Produktionstechnologie IPT

nachricht A big nano boost for solar cells
18.01.2017 | Kyoto University and Osaka Gas effort doubles current efficiencies

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Scientists spin artificial silk from whey protein

X-ray study throws light on key process for production

A Swedish-German team of researchers has cleared up a key process for the artificial production of silk. With the help of the intense X-rays from DESY's...

Im Focus: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Breaking the optical bandwidth record of stable pulsed lasers

24.01.2017 | Physics and Astronomy

Choreographing the microRNA-target dance

24.01.2017 | Life Sciences

Spanish scientists create a 3-D bioprinter to print human skin

24.01.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>