Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Microfabrication Breakthrough Could Set Piezoelectric Material Applications in Motion

21.11.2011
Integrating a complex, single-crystal material with "giant" piezoelectric properties onto silicon, University of Wisconsin-Madison engineers and physicists can fabricate low-voltage, near-nanoscale electromechanical devices that could lead to improvements in high-resolution 3-D imaging, signal processing, communications, energy harvesting, sensing, and actuators for nanopositioning devices, among others.

Led by Chang-Beom Eom, a UW-Madison professor of materials science and engineering and physics, the multi-institutional team published its results in the Nov. 18, issue of the journal Science. (Eom and his students also are co-authors on another paper, "Domain dynamics during ferroelectric switching," published in the same issue.)

Piezoelectric materials use mechanical motion to generate an electrical signal, such as the light that flashes in some children's shoe heels when they stomp their feet. Conversely, piezoelectrics also can use an electrical signal to generate mechanical motion—for example, piezoelectric materials are used to generate high-frequency acoustic waves for ultrasound imaging.

Eom studies the advanced piezoelectric material lead magnesium niobate-lead titanate, or PMN-PT. Such materials exhibit a "giant" piezoelectric response that can deliver much greater mechanical displacement with the same amount of electric field as traditional piezoelectric materials. They also can act as both actuators and sensors. For example, they use electricity to deliver an ultrasound wave that penetrates deeply into the body and returns data capable of displaying a high-quality 3-D image.

Currently, a major limitation of these advanced materials is that to incorporate them into very small-scale devices, researchers start with a bulk material and grind, cut and polish it to the size they desire. It's an imprecise, error-prone process that's intrinsically ill-suited for nanoelectromechanical systems (NEMS) or microelectromechanical systems (MEMS).

Until now, the complexity of PMN-PT has thwarted researchers' efforts to develop simple, reproducable microscale fabrication techniques.

Applying microscale fabrication techniques such as those used in computer electronics, Eom's team has overcome that barrier. He and his colleagues worked from the ground up to integrate PMN-PT seamlessly onto silicon. Because of potential chemical reactions among the components, they layered materials and carefully planned the locations of individual atoms. "You have to lay down the right element first," says Eom.

Onto a silicon "platform," his team adds a very thin layer of strontium titanate, which acts as a template and mimics the structure of silicon. Next comes a layer of strontium ruthenate, an electrode Eom developed some years ago, and finally, the single-crystal piezoelectric material PMN-PT.

The researchers have characterized the material's piezoelectric response, which correlates with theoretical predictions. "The properties of the single crystal we integrated on silicon are as good as the bulk single crystal," says Eom.

His team calls devices fabricated from this giant piezoelectric material "hyper-active MEMS" for their potential to offer researchers a high level of active control. Using the material, his team also developed a process for fabricating piezoelectric MEMS. Applied in signal processing, communications, medical imaging and nanopositioning actuators, hyper-active MEMS devices could reduce power consumption and increase actuator speed and sensor sensitivity. Additionally, through a process called energy harvesting, hyper-active MEMS devices could convert energy from sources such as mechanical vibrations into electricity that powers other small devices—for example, for wireless communication.

The National Science Foundation is funding the research via a four-year, $1.35 million NIRT grant. At UW-Madison, team members include Lynn H. Matthias Professor in Electrical and Computer Engineering Professor Robert Blick and Physics Professor Mark Rzchowski. Other collaborators include people at the National Institute of Standards and Technology, Pennsylvania State University, the University of Michigan, Argonne National Laboratory, the University of California at Berkeley, and Cornell University.

– Renee Meiller, (608) 262-2481, meiller@engr.wisc.edu

Chang-Beom Eom | Newswise Science News
Further information:
http://www.wisc.edu

More articles from Physics and Astronomy:

nachricht Climate cycles may explain how running water carved Mars' surface features
02.12.2016 | Penn State

nachricht What do Netflix, Google and planetary systems have in common?
02.12.2016 | University of Toronto

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

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

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>