Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Good Memory

Abstract:
On the way to plastic electronics: polymer-based dynamic random access memory (DRAM)

Good Memory

Posted on April 14, 2006

Smaller, lighter, more compact devices that can do more and more, work faster, and juggle more data—these demands are pushing conventional semiconductor technology up against its limits. In the future, plastics will have to take over. A number of polymeric electronic components have already been made. Researchers at the National University of Singapore and the Institute of Microelectronics in Singapore have now successfully produced DRAM storage based on a plastic.

The Singaporean team also recently made flash memory (a rewritable memory) and write-once read-many-times (WORM) memory based on polymers. Now they have introduced another type of memory, dynamic random access memory (DRAM), based on a polymer. In this “short-term” or “dynamic” memory, electronic devices temporarily store all processes—storage units are updated by refreshing voltage pulses.

In contrast to a semiconductor chip, which “keeps track” of data in the form of electrical charge, the “0” and “1” signals in polymer-based memory are stored as high and low conductivity, respectively. The researchers produced a special copolymer, a plastic whose long molecular chains are made of two different components that are finely tuned to each other. This polymer is embedded as a thin film between two electrodes. The polymer is initially in the OFF state, which is characterized by low conductivity. A barrier hinders the flow of electrons through the film. In order to “write” to the memory, a low voltage above a certain threshold (-2.8 V) is enough to switch the copolymer into a highly conducting state, the ON state. The memory is “read” by means of voltage pulses below the threshold. The secret behind this device is the combination of the barrier and a kind of “pit trap” for charge carriers. If the barrier is first overcome above the threshold, the pits are filled with charge carriers. The altered electrical field then causes the barrier to become ineffective. The current can then flow through the film unhindered. The pits are “shallow”, which allows the charge carriers to come out easily: If no voltage is applied for over two minutes they “climb” out of the pits on their own and the memory “forgets” its programming and returns to the OFF state. This is just what it should do as “dynamic” memory. “Erasing” the memory is accomplished by an opposing voltage pulse above +3.5 V. This immediately returns the memory to the original OFF state with empty traps. Renewed application of more than -2.8 V always returns the memory to its writeable state.

####


Author: En-Tang Kang, National University of Singapore (Singapore), www.chee.nus.edu.sg/staff/kang.html

Title: A Dynamic Random Access Memory (DRAM) Based on a Conjugated Copolymer Containing Electron-Donor and -Acceptor Moieties

Angewandte Chemie International Edition, 2006, 45, No. 18, 2947–2951, doi: 10.1002/anie.200504365

Contact:
Editorial office:
angewandte@wiley-vch.de

or David Greenberg (US)
dgreenbe@wiley.com

or Julia Lampam (UK)
jlampam@wiley.co.uk

Copyright © Angewandte Chemie

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

Memory Technology

SouthWest NanoTechnologies (SWeNT) Receives NIST Small Business Innovation Research (SBIR) Phase 1 Award to Produce Greater than 99% Semiconducting Single-Wall Carbon Nanotubes September 19th, 2014

IEEE International Electron Devices Meeting To Celebrate 60th Anniversary as The Leading Technical Conference for Advanced Semiconductor Devices September 18th, 2014

Promising Ferroelectric Materials Suffer From Unexpected Electric Polarizations: Brookhaven Lab scientists find surprising locked charge polarizations that impede performance in next-gen materials that could otherwise revolutionize data-driven devices August 18th, 2014

Can our computers continue to get smaller and more powerful? University of Michigan computer scientist reviews frontier technologies to determine fundamental limits of computer scaling August 13th, 2014

Materials/Metamaterials

Iranian Scientists Separate Zinc Ion at Low Concentrations September 20th, 2014

Iranian Researchers Synthesize Stable Ceramic Nanopowders at Room Temperature September 20th, 2014

Big Results Require Big Ambitions: Three young UCSB faculty receive CAREER awards from the National Science Foundation September 18th, 2014

Wear-resistant ceramic powder maximises component lifespan in high-stress applications: Innovnano’s nanostructured 3YSZ offers improved tribological performance for manufacturing components September 18th, 2014

Announcements

Iranian Scientists Separate Zinc Ion at Low Concentrations September 20th, 2014

Arrowhead to Present at BioCentury's NewsMakers in the Biotech Industry Conference September 19th, 2014

SouthWest NanoTechnologies (SWeNT) Receives NIST Small Business Innovation Research (SBIR) Phase 1 Award to Produce Greater than 99% Semiconducting Single-Wall Carbon Nanotubes September 19th, 2014

Toward optical chips: A promising light source for optoelectronic chips can be tuned to different frequencies September 19th, 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