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Handbook of Materials Modeling

Submitted by Anonymous (not verified) on
by S. Yip (Editor), 2005

Book Review
"A new guide to materials modeling largely succeeds in its aim to be the defining reference for the field of computational materials science and represents a huge undertaking..." -- by James Elliott | University of Cambridge, Materials Today, Volume 9, Issues 7-8, July-Aug 2006, Pages 51-52.

The first reference of its kind in the rapidly emerging field of computational approachs to materials research, this is a compendium of perspective-providing and topical articles written to inform students and non-specialists of the current status and capabilities of modelling and simulation. From the standpoint of methodology, the development follows a multiscale approach with emphasis on electronic-structure, atomistic, and mesoscale methods, as well as mathematical analysis and rate processes. Basic models are treated across traditional disciplines, not only in the discussion of methods but also in chapters on crystal defects, microstructure, fluids, polymers and soft matter. Written by authors who are actively participating in the current development, this collection of 150 articles has the breadth and depth to be a major contributor toward defining the field of computational materials. In addition, there are 40 commentaries by highly respected researchers, presenting various views that should interest the future generations of the community. Subject Editors: Martin Bazant, MIT; Bruce Boghosian, Tufts University; Richard Catlow, Royal Institution; Long-Qing Chen, Pennsylvania State University; William Curtin, Brown University; Tomas Diaz de la Rubia, Lawrence Livermore National Laboratory; Nicolas Hadjiconstantinou, MIT; Mark F. Horstemeyer, Mississippi State University; Efthimios Kaxiras, Harvard University; L. Mahadevan, Harvard University; Dimitrios Maroudas, University of Massachusetts; Nicola Marzari, MIT; Horia Metiu, University of California Santa Barbara; Gregory C. Rutledge, MIT; David J. Srolovitz, Princeton University; Bernhardt L. Trout, MIT; Dieter Wolf, Argonne National Laboratory.

Question about dislocation nucleation sites in strained silicon-on-insulator

Submitted by Zhen Zhang on

Electronic active device is built on the strained silicon-on-insulator (sSOI), e.g. strained Si layer on oxide, which in turn is bonded on bulk silicon wafer. Because no misfit dislocation can exist in strained silicon layer any more, will the dislocation be generated during later processing and operation? If there are still lots of dislocations in the strained silicon layer, where do they come from? Is there any experimental work to discover the dislocation nucleation sites? I guess they will nucleate from the triple junctions of gate-sSOI-cap, because the stress is singular in the triple junction. But I am not sure. So I want to know something about the experimental observations.

McMat 2007 Applied Mechanics and Materials Conference

Submitted by Ravi-Chandar on

The McMat 2007 conference, organized by the University of Texas on behalf of the Applied Mechanics and the Materials Divisions of the ASME, will be held in Austin, June 3-7, 2007.

We are now accepting proposals for symposia and abstracts of papers.

Saturated voids in interconnect lines due to thermal strains and electromigration

Submitted by Zhen Zhang on

Zhen Zhang, Zhigang Suo, Jun He

Thermal strains and electromigration can cause voids to grow in conductor lines on semiconductor chips. This long-standing failure mode is exacerbated by the recent introduction of low-permittivity dielectrics. We describe a method to calculate the volume of a saturated void (VSV), attained in a steady state when each point in a conductor line is in a state of hydrostatic pressure, and the gradient of the pressure along the conductor line balances the electron wind. We show that the VSV will either increase or decrease when the coefficient of thermal expansion of the dielectric increases, and will increase when the elastic modulus of the dielectric decreases. The VSV will also increase when porous dielectrics and ultrathin liners are used. At operation conditions, both thermal strains and electromigration make significant contributions to the VSV. We discuss these results in the context of interconnect design.


This has been published and the related references are listed here:

  • Z. Zhang, Z. Suo, and J. He, J. Appl. Physics, 98, 074501 (2005). link
  • J. He, Z. Suo, T.N. Marieb, and J.A. Maiz, Appl. Phys. Lett. 85, 4639 (2004). link

 

Ninth U.S. National Congress on Computational Mechanics

Submitted by Ling Liu on



USNCCM IX, July 22 - 26, 2007
Pre- & Post-Congress Short Courses, July 22 & 26, 2007
Hyatt Regency San Francisco
San Francisco, California

BACKGROUND AND SCOPE
From their inception in 1991, the biennial congresses of the United States Association for Computational Mechanics have become major scientific events, drawing computational engineers and scientists worldwide from government, academia, and industry. The Ninth U.S. National Congress on Computational Mechanics (USNCCM IX), hosted by the University of California, Berkeley, will feature the latest developments in all aspects of computational mechanics, and will broaden the definition of the discipline to include many other computation-oriented areas in engineering and sciences. From applications in nanotechnology and bioengineering, to recent advances in numerical methods and high-performance computing, the technical program will reflect the Congress theme of "Interdisciplinary Computation''. In addition to plenary lectures and minisymposia that highlight the latest trends in computational mechanics, pre- and post-conference short courses addressing advances in multiscale and multiphysics methods, as well as other topics, will be held. Numerous vendor exhibits from Bay Area and national companies and organizations are also planned. Detailed information on USNCCM IX can be found at:
http://me.berkeley.edu/compmat/USACM/main.html

George Rankine Irwin (26 February 1907 - 9 October 1998)

Submitted by Nanshu Lu on

Dr George Rankine Irwin (26 February 1907 - 9 October 1998) was an American scientist in the field of fracture mechanics and strength of materials. He was internationally known for his study of fracture of materials. Read more...

Also see his acceptance speech upon receiving the Timoshenko Medal.

Innovation Hall of Fame, University of Maryland.

Brain Storm and Carbon Nanotubes

Submitted by Zhen Zhang on

Last year, I attended the course ES139/239 in Division of Engineering and Applied Sciences, Harvard University, the innovation in science and technology. The final project of my group was about carbon nanotube (CNT). In the stage of popping up ideas, we did not consider any feasibility issues, and just used our imagination to create fancy ideas. I was inspired by other guys a lot, felt too excited after the evening brainstorm session, and wrote down the ideas I coined up. Some of them are not nonsense, e.g. replacing Cu by CNT as conductor in integrated circuit (IC). Later on, I find a piece of news in nanotoday (Dec. 2005) that the company Arrowhead Research was to provide $680,000 over two years to Duke University to develop technology for IC based on CNTs. Of course, I am not the first one to come up with this idea. But this means the random imaginative idea is very helpful and sometimes feasible. Another point I learned from this course is to write down at least one idea per day. Keep doing this, then you have a large pool of ideas. One year later, you have 365 ideas. Don’t expect every idea to be useful. Even if just one or two of them are great, it is worthy doing. Imagine that if the future technology originated from one of your ideas, you will contribute the society and feel fullness of ecstasy. If you can realize your idea, you can be a millionaire or billionaire, and then lie on the beach of Caribbean to enjoy the sunshine.