Featured Research

from universities, journals, and other organizations

Stacked, Packed Nanowires Hold Triplexed Megadata

Date:
April 23, 2004
Source:
University Of Southern California
Summary:
A novel transistor architecture using molecular-scale nanowire memory cells holds the promise of unprecedently compact data storage.

Memory on a nanowire: Simulation of memory cells holding 3 bits of data each formed spontaneously on an indium oxide nanowire by a process created at the USC Viterbi School of Engineering and the NASA Ames Research Center.
Credit: Image courtesy University Of Southern California

A novel transistor architecture using molecular-scale nanowire memory cells holds the promise of unprecedently compact data storage.

Researchers at the University of Southern California and the NASA Ames Research Center have successfully tested a self-assembled molecular memory device they say has the potential of holding 40 Gigabits per square centimeter -- a far greater density than any achieved on silicon.

Furthermore, says Chongwu Zhou, an assistant professor in the USC Viterbi School department of electrical engineering, because of the self-assembly feature, such ultra dense memory devices can likely be cheaper than the silicon flash memories now widely used in digital cameras, "memory sticks" and other applications.

According to a recent paper by Zhou and his group in Applied Physics Letters describing the technology, the density is achieved by the nanoscale (one millionth of a millimeter) size of the building blocks used,

( Ten nanometers is 0.0000004 inch; an average bacterium is about 1000 nanometers long; the smallest known virus about 20 nanometers long).

The USC/Ames system is still more compact because each memory cell can hold not just one bit of data but three, by virtue of having 8 separate, stable identifiable electronic states.

The USC/Ames system is already quite stable, holding information up to 600 hours. "We believe further work can increase the stability still further," the scientist said.

The USC/Ames researchers synthesized nanowires of indium oxide (In2O3) 10 nanometers in diameter and about 2000 nanometers long, by a "laser ablation" process that first vaporizes an indium containing compound, and then precipitates the indium out in a catalyzed process in which the wires form spontaneously as the indium reacts with ambient oxygen.

The researchers then placed the nanowires on a thin layer of quartz, and activated them by simply submerging them in a solutions of redox materials — various were tested — which self-assembled a layer of coating onto the wires, creating transistors.

The resulting transistors could be placed not in one activated state, but three distinct ones, by using different voltages to stimulate them. "We repeated tens of cycles for the endurance test for each memory operation and found that all the levels were distinguishable in the tested cycles," the authors wrote in their APL paper.

In the same paper, they also noted that the assembly process — a cold one — "represents a significant departure from the channel hot electron injection commonly used for silicon flash memory," The paper claims that the USC/Ames process requires lower power and is inherently less likely to introduce defects that can cause errors in the device.

The team included, besides Zhou, USC Viterbi School of Engineering graduate students Chao Li, Bo Lei, Daihua Zhang, Son Han, Tao Tang, Xialei Lu, and Zuqin Liu; and Wendy Fan, Sylvia Asano, Jie Han, and Meyya Meyyappan of Ames. Fan, Asano, and Han's contributions were underwritten by the Eloret Corporation, a Sunnyvale CA consulting firm working under contract to NASA.


Story Source:

The above story is based on materials provided by University Of Southern California. Note: Materials may be edited for content and length.


Cite This Page:

University Of Southern California. "Stacked, Packed Nanowires Hold Triplexed Megadata." ScienceDaily. ScienceDaily, 23 April 2004. <www.sciencedaily.com/releases/2004/04/040421234637.htm>.
University Of Southern California. (2004, April 23). Stacked, Packed Nanowires Hold Triplexed Megadata. ScienceDaily. Retrieved July 23, 2014 from www.sciencedaily.com/releases/2004/04/040421234637.htm
University Of Southern California. "Stacked, Packed Nanowires Hold Triplexed Megadata." ScienceDaily. www.sciencedaily.com/releases/2004/04/040421234637.htm (accessed July 23, 2014).

Share This




More Matter & Energy News

Wednesday, July 23, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Government Approves East Coast Oil Exploration

Government Approves East Coast Oil Exploration

AP (July 18, 2014) The Obama administration approved the use of sonic cannons to discover deposits under the ocean floor by shooting sound waves 100 times louder than a jet engine through waters shared by endangered whales and turtles. (July 18) Video provided by AP
Powered by NewsLook.com
Sunken German U-Boat Clearly Visible For First Time

Sunken German U-Boat Clearly Visible For First Time

Newsy (July 18, 2014) The wreckage of the German submarine U-166 has become clearly visible for the first time since it was discovered in 2001. Video provided by Newsy
Powered by NewsLook.com
Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Obama: U.S. Must Have "smartest Airports, Best Power Grid"

Reuters - US Online Video (July 17, 2014) President Barak Obama stopped by at a lunch counter in Delaware before making remarks about boosting the nation's infrastructure. Mana Rabiee reports. Video provided by Reuters
Powered by NewsLook.com
Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

Crude Oil Prices Bounce Back After Falling Below $100 a Barrel

TheStreet (July 16, 2014) Oil Futures are bouncing back after tumbling below $100 a barrel for the first time since May yesterday. Jeff Grossman is the president of BRG Brokerage and trades at the NYMEX. Grossman tells TheStreet the Middle East is always a concern for oil traders. Oil prices were pushed down in recent weeks on Libya increasing its production. Supply disruptions in Iraq fading also contributed to prices falling. News from China's economic front showing a growth for the second quarter also calmed fears on its slowdown. Jeff Grossman talks to TheStreet's Susannah Lee on this and more on the Energy Department's Energy Information Administration (EIA) report. Video provided by TheStreet
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins