Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Strain-Gating Piezotronics: Researchers Create New Class of Piezoelectric Logic Devices Using Zinc Oxide Nanowires

Georgia Tech researchers measure the performance of an array of zinc oxide nanodevices fabricated on a flexible polymer substrate. (Click image for high-resolution version. Credit: Gary Meek)
Georgia Tech researchers measure the performance of an array of zinc oxide nanodevices fabricated on a flexible polymer substrate. (Click image for high-resolution version. Credit: Gary Meek)

Abstract:
Researchers at the Georgia Institute of Technology have developed a new class of electronic logic device in which current is switched by an electric field generated by the application of mechanical strain to zinc oxide nanowires.

By John Toon

Strain-Gating Piezotronics: Researchers Create New Class of Piezoelectric Logic Devices Using Zinc Oxide Nanowires

Atlanta, GA | Posted on September 3rd, 2010

The devices, which include transistors and diodes, could be used in nanometer-scale robotics, nano-electromechanical systems (NEMS), micro-electromechanical systems (MEMS) and microfluidic devices. The mechanical action used to initiate the strain could be as simple as pushing a button, or be created by the flow of a liquid, stretching of muscles or the movement of a robotic component.

In traditional field-effect transistors, an electrical field switches - or "gates" - the flow of electrical current through a semiconductor. Instead of using an electrical signal, the new logic devices create the switching field by mechanically deforming zinc oxide nanowires. The deformation creates strain in the nanowires, generating an electric field through the piezoelectric effect - which creates electrical charge in certain crystalline materials when they are subjected to mechanical strain.

"When we apply a strain to a nanowire placed across two metal electrodes, we create a field, which is strong enough to serve as the gating voltage," said Zhong Lin Wang, a Regents professor in the Georgia Tech School of Materials Science and Engineering. "This type of device would allow mechanical action to be interfaced with electronics, and could be the basis for a new form of logic device that uses the piezoelectric potential in place of a gate voltage."

Wang, who has published a series of articles on the devices in such journals as Nano Letters, Advanced Materials and Applied Physics Letters, calls this new class of nanometer-scale device "piezotronics" because they use piezoelectric potential to tune and gate the charge transport process in semiconductors. The devices rely on the unique properties of zinc oxide nanostructures, which are both semiconducting and piezoelectric.

The transistors and diodes add to the family of nanodevices developed by Wang and his research team, and could be combined into systems in which all components are based on the same zinc oxide material. The researchers have previously announced development of nanometer-scale generators that produce a voltage by converting mechanical motion from the environment, and nanowire sensors for measuring pH and detecting ultraviolet light.

"The family of devices we have developed can be joined together to create self-powered, autonomous and intelligent nanoscale systems," Wang said. "We can create complex systems totally based on zinc oxide nanowires that have memory, processing, and sensing capabilities powered by electrical energy scavenged from the environment."

Using strain-gated transistors fabricated on a flexible polymer substrate, the researchers have demonstrated basic logic operations - including NOR, XOR and NAND gates and multiplexer/demultiplexer functions - by simply applying different types of strain to the zinc oxide nanowires. They have also created an inverter by placing strain-gated transistors on both sides of a flexible substrate.

"Using the strain-gated transistor as a building block, we can build complicated logic," Wang added. "This is the first time that a mechanical action has been used to create a logic operation."

A strain-gated transistor is made of a single zinc oxide nanowire with its two ends - the source and drain electrodes - fixed to a polymer substrate by metal contacts. Flexing the devices reverses their polarity as the strain changes from compressive to tensile on opposite sides.

The devices operate at low frequencies - the kind created by human interaction and the ambient environment - and would not challenge traditional CMOS transistors for speed in conventional applications. The devices respond to very small mechanical forces, Wang noted.

The Georgia Tech group has also learned to control conductivity in zinc oxide nanodevices using laser emissions that take advantage of the unique photo-excitation properties of the material. When ultraviolet light from a laser strikes a metal contact attached to a zinc oxide structure, it creates electron-hole pairs which change the height of the Schottky barrier at the zinc oxide-metal contact.

These conductivity-changing characteristics of the laser emissions can be used in tandem with alterations in mechanical strain to provide more precise control over the conducting capabilities of a device.

"The laser improves the conductivity of the structure," Wang noted. "The laser effect is in contrast to the piezoelectric effect. The laser effect reduces the barrier height, while the piezoelectric effect increases the barrier height."

Wang has called these new devices fabricated by coupling piezoelectric, photon excitation and semiconductor properties "piezo-phototronic" devices.

The research group has also created hybrid logic devices that use zinc oxide nanowires to control current moving through single-walled carbon nanotubes. The nanotubes, which were produced by researchers at Duke University, can be either p-type or n-type.

The research has been supported by the National Science Foundation (NSF), the Defense Advanced Research Projects Agency (DARPA), and the U.S. Department of Energy (DOE). In addition to Wang, the research team includes Wenzhuo Wu, Yaguang Wei, Youfan Hu, Weihua Liu, Minbaek Lee, Yan Zhang, Yanling Chang, Shu Xiang, Lei Ding, Jie Liu and Robert Snyder.

"Our work with strain-gated devices provides a new approach to logic operations that performs mechanical-electrical actions in one structural unit using a single material," Wang noted. "These transistors could provide new processing and memory capabilities in very small and portable devices."

####

For more information, please click here

Contacts:
Media Relations Assistance: John Toon or Abby Vogel Robinson

Copyright © Georgia Institute of Technology

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

'Exotic' material is like a switch when super thin April 18th, 2014

Innovative strategy to facilitate organ repair April 18th, 2014

Oxford Instruments Asylum Research Introduces the MFP-3D InfinityTM AFM Featuring Powerful New Capabilities and Stunning High Performance April 18th, 2014

Conductive Inks: booming to $2.8 billion by 2024 April 17th, 2014

Microfluidics/Nanofluidics

A*STAR's Simtech collaboration agreements to accelerate the growth and development of the microfluidics industry April 1st, 2014

Dolomite releases novel droplet-on-demand sequencing and droplet generation microfluidic system April 1st, 2014

Heat-Based Technique Offers New Way to Measure Microscopic Particles March 13th, 2014

New partnership between Malvern Instruments and RheoSense brings m-VROCi to industrial markets February 28th, 2014

NEMS

LetiDays Grenoble to Present Multiple Perspectives on Development, Challenges and Markets for the IoT April 14th, 2014

Columbia engineers make world's smallest FM radio transmitter: Team demonstrates new application of graphene using positive feedback November 18th, 2013

Revisiting quantum effects in MEMS: New calculations shows that the influence of quantum effects on the operating conditions of nanodevices has, until now, been overestimated November 15th, 2013

Leti Workshop at IEDM 2013 Will Present Latest Advances in Cost-effective and Power-efficient Technologies for the Future of the Semiconductor Industry November 6th, 2013

Govt.-Legislation/Regulation/Funding/Policy

'Exotic' material is like a switch when super thin April 18th, 2014

Innovative strategy to facilitate organ repair April 18th, 2014

Novel stapled peptide nanoparticle combination prevents RSV infection, study finds April 17th, 2014

INSCX™ exchange to present Exchange trade reporting mechanism for engineered nanomaterials (NMs) to UK regulation agencies, insurers and upstream/downstream users April 17th, 2014

Possible Futures

Virus structure inspires novel understanding of onion-like carbon nanoparticles April 10th, 2014

Local girl does good March 22nd, 2014

Surface Characteristics Influence Cellular Growth on Semiconductor Material March 12th, 2014

The "Tipping Point" February 12th, 2014

Academic/Education

Director Wally Pfister joins UC Berkeley neuroengineers to discuss the science behind ‘Transcendence’ April 7th, 2014

First annual science week highlights STEM pipeline and partnerships: UB, SUNY Buffalo State and ECC team up with the City of Buffalo and its schools for April 7-11 events April 3rd, 2014

Global 450 consortium announces new general manager of internal operations: TSMC’s Cheng-Chung Chien Receives Unanimous Support, Brings History of Innovation and Efficiency to Global Consortium of Companies Driving Industry Transition to 450mm Wafer Technology March 26th, 2014

NanoTecNexus to Host "Chemistry of Wine" Fundraiser in Support of STEM Education - Collaborations Key to Success - March 20th, 2014

MEMS

LetiDays Grenoble to Present Multiple Perspectives on Development, Challenges and Markets for the IoT April 14th, 2014

Rainbow-catching waveguide could revolutionize energy technologies: By slowing and absorbing certain wavelengths of light, engineers open new possibilities in solar power, thermal energy recycling and stealth technology March 28th, 2014

Micro systems with big commercial potential featured in SPIE journal: Special section in Journal of Micro/Nanolithography, MEMS, and MOEMS highlights emerging MOEMS technologies March 25th, 2014

Martini Tech Inc. Starts to Offer GaN Deposition Service by MOCVD March 25th, 2014

Molecular Machines

Structural Insights into the Inner Workings of a Viral Nanomachine April 3rd, 2014

Big data tackles tiny molecular machines:Rice University technique able to analyze conformations of complex molecular machines March 14th, 2014

Advantages emerge in using nanostructured material in the forging process of mechanical components February 28th, 2014

Nanomotors are controlled, for the first time, inside living cells February 10th, 2014

Chip Technology

'Exotic' material is like a switch when super thin April 18th, 2014

Scientists open door to better solar cells, superconductors and hard-drives: Research enhances understanding of materials interfaces April 14th, 2014

Obducat has launched a new generation of SINDRE® Nano Imprint production system April 11th, 2014

Scientists in Singapore develop novel ultra-fast electrical circuits using light-generated tunneling currents April 10th, 2014

Sensors

Transparent Conductive Films and Sensors Are Hot Segments in Printed Electronics: Start-ups in these fields show above-average momentum, while companies working on emissive displays such as OLED are fading, Lux Research says April 17th, 2014

Biologists Develop Nanosensors to Visualize Movements and Distribution of Plant Stress Hormone April 15th, 2014

LetiDays Grenoble to Present Multiple Perspectives on Development, Challenges and Markets for the IoT April 14th, 2014

In latest generation of tiny biosensors, size isn't everything: UCLA researchers overturn conventional wisdom on nanowire-based diagnostic devices April 11th, 2014

Nanoelectronics

Better solar cells, better LED light and vast optical possibilities April 12th, 2014

Catching the (Invisible) Wave: UC Santa Barbara researchers create a unique semiconductor that manipulates light in the invisible infrared/terahertz range, paving the way for new and enhanced applications April 11th, 2014

Nanotech Business Review 2013-2014 April 9th, 2014

Preview of Hands-on Nanotechnology Demos at ‘Chemistry of Wine’ Fundraiser to Show Nanotech Magic April 8th, 2014

Announcements

'Exotic' material is like a switch when super thin April 18th, 2014

Innovative strategy to facilitate organ repair April 18th, 2014

Oxford Instruments Asylum Research Introduces the MFP-3D InfinityTM AFM Featuring Powerful New Capabilities and Stunning High Performance April 18th, 2014

Transparent Conductive Films and Sensors Are Hot Segments in Printed Electronics: Start-ups in these fields show above-average momentum, while companies working on emissive displays such as OLED are fading, Lux Research says April 17th, 2014

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







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE