Materials Science and Engineering for the 1990s Maintaining Competitiveness in the Age of Materials (1989) / Chapter Skim
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Appendix D: Instrumentation
Appendix D: Instrumentation
Pages 255-268
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From page 255... ...
The principal thesis of this appendix is that, within large areas related to materials research in the United States, 255
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From page 256... ...
commitment to instrumentation in materials research have become increasingly apparent in recent years. The current shortage of state-of-the-art instrumentation for preparing and characterizing materials is a problem that has been discussed by several national study groups and has been addressed by special instrumentation programs in several federal funding agencies.
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From page 257... ...
The committee believes that cooperation of this kind can and should be improved in the United States. If the United States is to stay at the forefront of materials research, then major resources must be devoted to the development of instrumentation, and special attention must be paid to the transfer of innovative instrumentation technology to research laboratories, to commercial instrument manufacturers, and eventually to the industries that will use this technology.
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From page 258... ...
Another example of how state-sponsored laboratories can play central roles in the development of new instrumentation is the German Max Planck institutes. The interaction between universities, government laboratories, and instrument companies must be enhanced with the objective of creating a healthy and expanding commercial instrumentation community that serves the needs of U.S.
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From page 259... ...
This goal was finally reached in 1987. Once again, one can see that the materials research community has been unwilling or unable to pay adequate attention to instrumentation and has had to depend on federal funding agencies not only for money but also for help in setting priorities.
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From page 260... ...
universities is that, unless some other segment of our scientific community such as federal or industrial laboratories takes new initiatives in this area, our materials research community will fall behind its international competition in its experimental capabilities. In the committee's discussions with funding agencies and with individual materials scientists, it frequently heard the opinion that instrument development is incompatible with the operation of U.S.
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From page 261... ...
In an attempt to understand what is happening in instrument development, the committee chose to focus primarily on one part of materials research, specifically, surface science. Surface science is a particularly crucial and active part of materials research, where, historically, there has been a large effort in instrument development.
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From page 262... ...
The fact that an instrumentation program that was pushing back the frontiers of surface science was phased out at a major, federally operated U.S. laboratory is an especially dramatic illustration of the low priority placed on instrument development in this country.
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From page 263... ...
The characteristic losses seen in the scattered beam measure the vibrational modes of molecules adsorbed on the surface or the phonon modes of the clean surface. The basic concepts of this experiment as well as the instrumentation were developed to study molecules in the gas phase.
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From page 264... ...
. Mueller's group in Erlangen, West Germany, has developed new LEED optics and a very fast data acquisition system that allow them to study diffuse low-energy scattering from surfaces as well as scattering by adsorbates that are damaged by the beam in conventional LEED systems.
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From page 265... ...
The crucial breakthrough was the invention of an electron gun that had sufficient brightness to achieve high resolution in a scanning mode. Effective use of high-performance electron lenses based on the work of West Germans and, of necessity, UHV techniques resulted in development of a scanning electron beam system capable of focusing a current on the order of 1 nA into a spot less than 5 angstroms in diameter.
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From page 266... ...
This class of measurement techniques was first demonstrated in Switzerland in 1969. It was extended by using synchrotron sources and photoelectron energy analysis about 10 years later at a West German government laboratory with an excellent support staff and large financial resources.
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From page 267... ...
The NBS spin analyzer has been used on a scanning electron microscope to measure the spin polarization of secondary electrons emitted from a magnetic material and thereby obtain images of magnetic microstructures. A prototype commercial instrument of this type has also been built and tested by PHI and is expected to reach the market in the near future.
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From page 268... ...
268 APPENDIX D: INSTRUMENTATION far behind research groups in West Germany in the use of these techniques. Exciting new surface physics is coming from elastic and inelastic scattering experiments, for example, the soliton-like reconstruction of the (1 11)
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