Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

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

Strem Chemicals and Dotz Nano Ltd. Sign Distribution Agreement for Graphene Quantum Dots Collaboration February 21st, 2017

Research opens door to smaller, cheaper, more agile communications tech February 16th, 2017

Scientists determine precise 3-D location, identity of all 23,000 atoms in a nanoparticle: Berkeley Lab researchers help to map iron-platinum particle in unprecedented detail February 6th, 2017

Investigations of the skyrmion Hall effect reveal surprising results: One step further towards the application of skyrmions in spintronic devices December 28th, 2016

Materials/Metamaterials

Sandia use confined nanoparticles to improve hydrogen storage materials performance: Big changes from a small package for hydrogen storage February 25th, 2017

Atom-scale oxidation mechanism of nanoparticles helps develop anti-corrosion materials February 24th, 2017

EmTech Asia breaks new barriers with potential applications of space exploration with NASA and MIT February 22nd, 2017

Molecular phenomenon discovered by advanced NMR facility: Cutting edge technology has shown a molecule self-assembling into different forms when passing between solution state to solid state, and back again - a curious phenomenon in science - says research by the University of Wa February 22nd, 2017

Announcements

Sandia use confined nanoparticles to improve hydrogen storage materials performance: Big changes from a small package for hydrogen storage February 25th, 2017

New nano approach could cut dose of leading HIV treatment in half February 24th, 2017

Atom-scale oxidation mechanism of nanoparticles helps develop anti-corrosion materials February 24th, 2017

Atomic force imaging used to study nematodes: KFU bionanotechnology lab (head - Dr. Rawil Fakhrullin) has obtained 3-D images of nematodes' cuticles February 23rd, 2017

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