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Correction The figure below, part of the article Microscopic Properties of Thin Films: Learning About Point Defects, by A. Ourmazd, M. Scheffler, M. Heinemann, and J-L. Rouviere, was run in black and white in the December MRS Bulletin. Following is the color version.

GaAs

Structure of Growing Crystal and its Composition Simultaneously Observed An instrument originally conceived by Shozo Ino of the Science Department of the University of Tokyo and developed by Japan Vacuum Technology allows researchers to measure the form and elemental structure of the two-dimensional distribution of a growing crystal. Called a "totalreflection-angle x-ray spectroscopy observation instrument of molecular layer growth," the device allows measurements indispensable for precisely controlling the composition and structure of semiconductors and other materials during fabrication. It is necessary to observe the composition, crystalline structure, and form of surface elements of films produced for microelectronics during their growth. Using this technology, the surface of a growing film is scanned by a slightly convergent high-speed electron beam. The crystalline structure and form of the surface can be observed using diffracted electron beams; the elemental composition of the surface can also be observed using the emitted characteristic x-rays. Both can be observed simultaneously in real time as a two-dimensional image. F.S. Myers

DOE, Cray to Work on Massively Parallel Processing

Ourmazd, Kim & Taylor (A T&TBell Labs)

Figure 1. (a) Chemical lattice image of a GaAs quantum well between its two Alo.4Gao.6As barriers. Note that although the structure of the sample is zinc-blende everywhere, the image changes strongly as the composition changes across the interface, (b) Three-dimensional plot showing the result of pattern recognition analysis of the chemical lattice image shown in (a). Height represents the local composition, and color changes represent statistically significant changes in the composition.

The Department of Energy and Cray Research Inc. have entered into a preliminary agreement calling for Los Alamos and Lawrence Livermore National Laboratories to work with the supercomputer maker to develop massively parallel processing to enhance the labs' capabilities and U.S. firms' competitiveness in the global market. Through this agreement, jointly funded at $70 million over three years, the two DOE labs and Cray will work together toward creating operating systems and capabilities for use on Cray's massively parallel processing (MPP) computer systems. Four areas—environmental modeling, defense systems, materials design, and advanced manufacturing—will be among the most direct beneficiaries. The labs have already held talks with several U.S. firms, including potential partners from the manufacturing, chemical, petroleum, aeronautical, and environmental sectors. The agreement in part will focus on modeling these specific computer-related goals: to reduce and contain pollution, improve manufacturing processes, and design the next