Skip to Main Content

Latest News

April 12, 2010
Volume 88, Number 15
p. 6
Article appeared online April 9, 2010

Data Storage Goes Organic

Materials Science: Device relies on changes in azo conductivity

Sophie Rovner

Good Memory: Data-storage device sandwiches a layer of an azo compound (structure shown) between indium tin oxide (ITO) and aluminum electrodes.
  • Print this article
  • Email the editor

Latest News



October 28, 2011

Speedy Homemade-Explosive Detector

Forensic Chemistry: A new method could increase the number of explosives detected by airport screeners.

Solar Panel Makers Cry Foul

Trade: U.S. companies complain of market dumping by China.

Novartis To Cut 2,000 Jobs

Layoffs follow similar moves by Amgen, AstraZeneca.

Nations Break Impasse On Waste

Environment: Ban to halt export of hazardous waste to developing world.

New Leader For Lawrence Livermore

Penrose (Parney) Albright will direct DOE national lab.

Hair Reveals Source Of People's Exposure To Mercury

Toxic Exposure: Mercury isotopes in human hair illuminate dietary and industrial sources.

Why The Long Fat?

Cancer Biochemistry: Mass spectrometry follows the metabolism of very long fatty acids in cancer cells.

Text Size A A

title

A data-storage system based on a new azo compound could increase the memory capacity of future electronic devices.

Most electronic memory systems use binary data storage, in which data are recorded as a string of zeros and ones. However, a few ternary systems—mostly experimental—have been developed that record data as zero, one, or two. In principle, the additional value means that a ternary system can hold much more data than a binary system does in a given amount of space within a storage device.

Now, Jianmei Lu, Hongwei Gu, and colleagues at Soochow University, in Suzhou, China, have devised a new ternary system (J. Am. Chem. Soc., DOI: 10.1021/ja910243f). The researchers synthesized the azo compound and sandwiched it between indium tin oxide (ITO) and aluminum electrodes. Each aluminum electrode, along with the small region of the azo material and ITO directly below it, serves as a memory storage unit, akin to the individual magnetized patches in which data are stored on a hard-drive disk.

Applying a voltage to an aluminum electrode permanently alters the density of molecular stacking—and the ease with which electrons flow—in the azo material below that electrode. The strength of the applied voltage determines whether that region of the azo layer ends up in a low-, medium-, or high-conductivity state, corresponding to zero, one, or two, respectively.

Lu and Gu’s prototype is a “write once, read many times” device, which is useful for permanent data storage. The researchers are looking for new materials that allow data to be erased and rewritten.

The proof-of-concept device is the first in which an organic molecule reliably provides three distinct, electrically switchable states for nonerasable memory storage, according to University of Pennsylvania materials scientist Ritesh Agarwal. Agarwal’s group previously developed a reliable erasable ternary data-storage system based on inorganic materials that change conductivity as an electric field switches the compounds from an amorphous to crystalline state and back (Nano Lett. 2008, 8, 2056).

Chemical & Engineering News
ISSN 0009-2347
Copyright © 2011 American Chemical Society
  • Print this article
  • Email the editor

Services & Tools

ACS Resources

ACS is the leading employment source for recruiting scientific professionals. ACS Careers and C&EN Classifieds provide employers direct access to scientific talent both in print and online. Jobseekers | Employers

» Join ACS

Join more than 161,000 professionals in the chemical sciences world-wide, as a member of the American Chemical Society.
» Join Now!