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ANGRY Residents of Anniston, Ala., marched in protest on Aug. 19,2001.

ORDERLY Randomly oriented silicon nanowires (background)can be organized into centimeter-sized patterns of crossed nanowire arrays (10 10 in the large inset).

P O L L U T I O N

MONSANTO, SOLUTiA SHELL OUT ON PCBS Firms to pay $600 million to settle claims by residents of Anniston, Ala.

M ONSANTO AND SOLUTIA I its chemicals business as Solutia will pay a combined $600 in 1997 Pharmacia & Upjohn million to settle claims of bought Monsanto in 2000 and more than 20,000 residents of later spun it off as an agricultural Anniston, Ala., that their bodies products company and property were polluted with In Anniston, some of the now-polychlorinated biphenyls. banned PCBs entered local wa-

The agreement, announced on terways, and tests show that Aug. 20, settles two PCB-relat- some local residents have d e ed cases, one in federal court with vated levels of the substances in about 17,000 plaintiffs and a sec- their bodies (C&EN, May 13, ond in state court with 3,500 2002, page 27). plaintiffs. The plant in Anniston Under the settlement, Mon-that made PCBs between 1929 santo will provide approximately and 1971 was owned for decades $390 million in cash, commer-by Monsanto. Monsanto spun off I cial insurance will cover about

$160 million, and Solutia will kick in $50 million over a decade.

"The global settlement is in the best interest of Monsanto and our shareowners," company President and CEO Hugh Grant comments. The settlement removes a great risk the uncertain length and outcome of l i t igation to Monsanto shareholders, he says.

Solutia Chairman and CEO John C. Hunter III says, "We're glad to have this litigation behind us."The settlement puts the company in a better position to handle its financial challenges, he says.

In addition to the settlement dollars from Monsanto and Solutia, Pfizer, which purchased Pharmacia in April, will fund more than $75 million in environmental health care programs, including a clinic and research facility, in Anniston. CHERYLH0GUE

N A N O E L E C T R O N I C S

RAPID ASSEMBLY Method forms ordered, nanosized circuit elements on multiple length scales

ASOLUTION-BASED METHOD for assembling nanowire structures from the bot

tom up with spatial control on several length scales, ranging from nanometers to centimeters, has been demonstrated by scientists at Harvard University Re

searchers there have shown that large numbers of uniform and hierarchically ordered nanoscale circuit elements can be prepared simultaneously using a simple and adaptable technique.

Driven by potential benefits of ultra-high-density microelectronics, researchers have developed and studied various test devices, such as field-effect transistors and light-emitting diodes, that are based on nanometer-scale components. Although the studies have advanced the field toward the sophisticated logic and memory circuitry, in general, the tiny devices have been assembled one at a time because of the limitations of available fabrication methods.

Now, Harvard chemistry professor Charles M. Lieber and coworkers Dongmok Whang, Songjin, and Yue Wu have shown that numerous basic circuit components can be constructed simultaneously using a straightforward procedure that controls the positions of nanowires or other building blocks and the devices constructed from them on multiple length scales [Nano Lett., published online Aug. 5, http:// dx.doi.org/10.1021/nl0345062].

In one demonstration, the Harvard group prepared ordered films of silicon nanowires using the Langmuir-Blodgett method, which provides control over the nanowire spacings on a length scale ranging from nanometers to micrometers. Then the team used layer-by-layer deposition methods and photolithography to construct arrays of crossed nanowire junctions, which serve as functional circuit components, forming a regular pattern across an area of several square centimeters. MITCH JAC0BY

http://www.cen-online.orghttp://http://dx.doi.org/10.1021/nl0345062

NANOELECTRONICSRAPID ASSEMBLY