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Midsize Facilities: The Infrastructure for Materials Research (2006)

Chapter: 1. Nature and Importance of Midsize Facilities

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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
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1
The Nature and Importance of Midsize Facilities

Midsize multiuser facilities play a major role in materials research. They give a broad range of users access to equipment and expertise for fabricating, characterizing, and measuring the properties of materials. The capabilities offered by midsize facilities are generally more wide ranging and much more expensive than are those encountered in a single investigator’s laboratory. The sharing of resources has therefore become a necessity, at the same time presenting increasing opportunities for enhancing interdisciplinary research, contributing to the development of cutting-edge instrumentation, and educating the next generation of researchers.

According to the recent National Science Board report Science and Engineering Infrastructure for the 21st Century,

An increasing amount of the equipment and systems that enable the advancement of research are large-scale, complex, and costly. “Facility” is frequently used to describe such equipment because typically the equipment requires special sites or buildings to house it and a dedicated staff to effectively maintain the equipment.1

Today, scientific advances require access to sophisticated facilities and instrumentation. The role of such facilities in materials synthesis, fabrication, character-

1  

National Science Board, Science and Engineering Infrastructure for the 21st Century: The Role of the National Science Foundation, NSB 02-190, Arlington, Va.: National Science Foundation, 2003, p. 8.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
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ization, and measurement is steadily increasing. In fact, these facilities are essential to the scientific infrastructure of the nation (see Box 1.1, “Growth in the Trend Toward Collaboration and Centralized Facilities”). There are significant opportunities for accelerating scientific advances in materials and nanotechnology research by invigorating such facilities and allocating their resources to best effect. Accordingly, the committee reemphasizes the importance of midsize facilities.

THE MANY ROLES OF MIDSIZE FACILITIES

Facilities to fabricate, test, and characterize novel materials are increasingly essential to the development of advanced materials and technology. These facilities are required by users with diverse backgrounds and interests, ranging from the

BOX 1.1
Growth in the Trend Toward Collaboration and Centralized Facilities

In addition to possessing intrinsic intellectual excitement, science and technology have been viewed historically as the key to growth in the national economy. The federal government has strongly supported research at universities and at national laboratories, while many corporations have established their own major research laboratories. University-based materials research originally consisted of individual investigators pursuing their own areas of interest and obtaining the necessary research tools by collaborating with other researchers or by grant funding. This approach has led to the proliferation of instruments with much duplication and, in some cases undoubtedly, inefficiency. The national laboratories have focused on the acquisition of analytical instruments and the establishment of central facilities to serve different research groups.

Corporate research has evolved in two directions, one consisting of efforts by individual investigators to enrich the pool of scientific knowledge that underpins the corporation, the other focusing on research and development that are directly relevant to the corporation’s products or new growth markets. The establishment of such central facilities within industrial corporations enhanced both of these routes, although some individual investigators had their own instruments.

Major advances in materials research have been achieved by all of the approaches referred to above. Nonetheless, leaders within the materials community began to believe that the problems and needs of the science and technology base were not being as efficiently addressed by the individual-investigator approach as might be achieved by collaboration.a The first major effort to gain productivity “greater than the sum of the parts” was made by the Advanced Research Projects Agency in 1960, with the establishment of the Materials Research Laboratories at a handful of research universities (as part of the Department of Defense Interdisciplinary Laboratory program). These laboratories were designed to bring together individuals from different disciplines to foster the exchange of ideas and to address major materials problems needing the collaborative efforts of groups of scientists and engineers.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
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basic physics of matter to the manufacture of working devices. They are situated in research universities, in national laboratories, and within private enterprises. Major industrial companies such as IBM, Intel, and GE have their own facilities that are restricted largely to in-house research and development. Future technological developments are critically dependent on sound, long-term facility infrastructure.

The recent surge of activity in nanotechnology and the increasing miniaturization of devices have led to a central role for materials research in this technological endeavor. For instance, as the dimensions of transistors—the essential elements of microelectronic circuits and computer microprocessors—go below 90 nanometers (nm), the traditional silicon oxide polysilicon structures must be replaced by higher-performance materials (see Figure 1.1). The discovery of carbon nanotubes (either conducting or semiconducting) by high-resolution electron microscopy

This new approach to university research included the establishment of central facilities for a variety of functions, ranging from cryogenics research to materials synthesis and characterization. These facilities were equipped with state-of-the-art instruments and had professional and technical staff to serve the researchers’ needs. The investigators were free to focus on the research without having to develop, fund, and operate the infrastructure necessary for their research. This new paradigm had considerable merit, and many funding agencies began to support the establishment of centralized facilities to serve the needs of multiple investigators. Today, centralized facilities are the rule rather than the exception.

The scale of research and development activities in the production, characterization, and optimization of new and advanced materials has grown significantly in recent years. This growth has been accelerated by the international excitement about and investment in nanoscience and nanotechnology.

The breadth of activities in these areas requires collaborative approaches and the use of a wide variety of highly sophisticated instrumentation and equipment. Such scientific instruments are expensive, and skilled technical staff are required to maintain the equipment and to train and guide users (often students and postdoctoral associates) to obtain the best results. The instruments play an important role not only in advancing the science and engineering of materials but also in training students to use and understand the capabilities and limitations of particular techniques.

Finally, materials characterization is often not a routine exercise. Instead, it is an investigative tool without which it is impossible to reach the basic understanding that leads to materials optimization and the invention of new applications, devices, and even materials systems.

a  

See, for instance, Attachment 2, “International Benchmarking of US Materials Science and Engineering Research,” in National Academy of Sciences, National Academy of Engineering, Institute of Medicine, Experiments in International Benchmarking of US Research Fields, Committee on Science, Engineering, and Public Policy, Washington, D.C.: National Academy Press, 2000.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
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FIGURE 1.1 The decreasing gate oxide thickness of transistors used in modern personal computers. Courtesy of Lucent Technologies Bell Labs.

and the fabrication of semiconductor nanowires on the 1 to 10 nm scale could possibly bring about the design of completely different electronic devices.

In another area, the promise of organic light-emitting diodes and photovoltaic thin films is likely to transform displays and solar energy panels, and ceramic fuel cell technologies operating at lower temperatures could greatly enhance energy-creating efficiency. Likewise, the combination of biological and inorganic processes for self-replication could transform capabilities for manufacturing large-area nanoscale products.

Basic research into new materials and methods of synthesis is thus becoming highly interdisciplinary and increasingly dependent on the availability of centralized tools. Its importance to the competitiveness of U.S. industry is paramount. The question then arises as to how this research can be performed efficiently and well.

Enabling Research

Nanoscience and nanotechnology represent strong examples of research dependent on midsize facilities (see Figures 1.2 and 1.3). The equipment required to

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

FIGURE 1.2 Diffractive optics such as these Fresnel zone plates have enabled major advances in soft x-ray microscopy for biological applications, spatially resolved hard x-ray microdiffraction for materials characterization, and even neutral atom optics that require freestanding structures. A germanium-phase zone plate is shown in (a) and (b) and a freestanding silicon zone plate is shown in (c). These structures are formed by electron-beam lithography and reactive ion etching, key tools for nanofabrication facilities. Courtesy of Lucent Technologies Bell Labs.

fabricate nanodevices is typically too expensive for a single investigator, or sometimes even for a single institution, and requires a combination of specialized skills that are not normally found in the laboratory of one investigator or academic department. As a consequence, several nanofabrication facilities have been established at universities and national laboratories. For example, the development of the instrument that uses focused-ion beams has played an important role in providing new capabilities for the fabrication of micro- and nanostructures. These facilities have enabled new research in biological and chemical sensors, gene chips, nanofluidics, molecular electronics, self-assembled monolayers, and integrated sensors.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

FIGURE 1.3 High-resolution transmission electron micrograph of crystals grown within a single-walled carbon nanotube. The synthesis and characterization of one-dimensional crystals with a well-specified chemistry, size, and crystal structure present a formidable challenge for materials chemistry and analysis. In this image, two layers of coordinated potassium iodide crystals grown within the single-walled carbon nanotubes are shown, as indicated by the arrows. An enhanced image-restoration technique developed by A. Kirkland and O. Saxton at Cambridge University makes possible an atom-by-atom reconstruction of these crystals, the first time that crystallography has been attempted on such a scale. Courtesy of J. Sloan and J. Hutchison, Oxford University.

Another aspect of the important role played by midsize facilities in advancing materials science is illustrated in the area of nanocharacterization. Nanocharacterization facilities are inevitably coupled with nanofabrication facilities—researchers always need to examine closely what they have created! (See Figure 1.4 for an example.) The collection of instruments required is again too expensive and

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

FIGURE 1.4 A single strand of gold atoms: (left) the structure as imaged with a transmission electron microscope (TEM) where the gold atoms appear in dark contrast, and (right) a diagram of what is being observed where the gold atoms appear in yellow. A single strand of gold atoms was first observed to exist suspended in free space between electrodes with an atomic spacing of 0.40 nm on average, extremely long compared with the nearest-neighbor distance, 0.29 nm, in crystalline gold. Quantum point contacts are structures (generally metallic) in which a “neck” of atoms just a few atomic diameters wide (that is, comparable to the conduction electrons’ Fermi wavelength) bridges two electrical contacts. They can be prepared by contacting a metal surface with a scanning tunneling microscope and by other methods. Courtesy of K. Takayanagi, Tokyo Institute of Technology, and Y. Kondo, JEOL, Ltd.

too specialized to be established in the laboratories of individual investigators or departments. High-resolution transmission electron microscopes (TEMs), scanning electron microscopes, multimode scanning probe microscopes, and focused-ion beams are examples of the equipment found in a modern nanocharacterization facility.

The operating techniques and some of the specialized accessories for such facilities must often be developed by experienced staff using the infrastructure that the facilities provide. From time to time, a commercial instrument requires signifi-

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

cant alteration or enhancement before it can be employed successfully to address an important scientific or technological problem. These types of instrument enhancements or extensions often lead to major new capabilities that extend far beyond the original application and open up new research areas. Midsize facilities provide the natural environment for this work: an individual investigator does not have the resources to pursue it, and the (often-oversubscribed) largest facilities cannot afford the time and energy to customize or specialize an apparatus for each user’s needs.

Instrument Development

Many facilities contribute directly to the development of the fundamental instrumentation around which these facilities are built, and thereby advance the field markedly. The experience that researchers gain by having access to the most advanced instrumentation, plus the experience gained by facilities in meeting—or in not having the instrumentation to meet—users’ needs can spur the development of the next generation of instruments (see Box 1.2, “Increasing Sophistication of Instrumentation and Associated Trends”). With a healthy combination of technical staff, existing tools and equipment, and financial resources, midsize facilities are often more able than are single investigators or large national facilities to tackle the instrumentation challenges brought to them by users. Examples include developments in electron microscopy for “wet” and “cold” sample stages, piezoelectric drivers for in situ sample testing, and, more recently, demonstration by researchers at Northwestern University of a new technique that is capable of actively monitoring and controlling crystallization as it proceeds in real time.

Cross-Disciplinary Science

The development of biosensors and gene chips illustrates another important research thrust occurring at such facilities. It is becoming increasingly evident that many important scientific and technological opportunities lie at the intersection of traditional disciplines. Facilities with advanced instrumentation and skilled support staff enhance the effectiveness of interdisciplinary groups and make it possible for people with limited previous training to utilize techniques developed outside their fields. In facilitating interactions among people from different disciplines and encouraging cooperation, facilities act as meeting grounds and provide exposure to research endeavors that emphasize joint effort, planning, and cooperation.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

BOX 1.2
Increasing Sophistication of Instrumentation and Associated Trends

The increasing sophistication of instrumentation can be exemplified by the following descriptions of transmission electron microscopy, x-ray crystallography, scanning probe microscopy, the focused-ion beam, and electron-beam writers.


Transmission Electron Microscopy


In the decades from the 1960s to the 1980s, transmission electron microscopes (TEMs) were used mostly to examine the microstructure of alloys and ceramics, with diffraction contrast as the imaging mechanism. The addition of x-ray energy dispersive spectroscopy and the improvement of resolution allowed chemical analysis on the 10 nm scale, enabling the first routine, direct images of the atomic structure of materials. By the 1990s, electron energy loss spectroscopy and energy-filtered imaging brought about the possibility of chemical mapping at the 1 nm level and the determination of chemical ionization and bonding states.

Now, aberration correction and monochromators are extending all of these capabilities—within one compact machine that fits into a normal-size room—to the subangstrom (0.1 nm) scale! (See Figure 1.2.1 for a diagram of the evolution described here.) Aberration-corrected microscopy provides a direct image with fewer opportunities for “artifacts,” or incorrect image information. Uncorrected microscopy can achieve subangstrom resolution by combining a collection of many micrographs to achieve an image, but it also increases the introduction of artifacts. Concomitant with these developments, the approximate cost of these instruments has increased by a factor of 50, from about $0.1 million to $5 million or more for a fully aberration-corrected TEM.

In fact, in September 2004, Oak Ridge National Laboratory (ORNL) researchers, using a state-of-the-art aberration-corrected microscope and new computerized imaging technology, pushed back the barrier with respect to the size of what can be seen.a Led by ORNL researcher Stephen Pennycook, the team examined a silicon crystal and imaged atoms that are only 0.78 angstrom apart, demonstrating reliable subangstrom resolution with electron microscopy (see Figure 1.2.2).


X-ray Crystallography


It is well known that many invaluable achievements in x-ray crystallography have been realized at the very successful (large-scale) synchrotron facilities. Recently, it was announced that technological innovations are likely to bring about a new generation of small-scale synchrotron sources far exceeding the capabilities of rotating anode x-ray generators. These small-scale synchrotron sources would likewise be able to fit into a normal-size laboratory—an advance that would then make them easily available for use by many universities and institutions. This advance—while likely to enable significant new opportunities—will add to the strain on the midscale instrumentation budget (see Box 1.3, “Desktop-Size Synchrotron Radiation Sources,” for more details).

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
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FIGURE 1.2.1 Evolution of electron microscopy, 1930 to the present, organized by improvements in spatial resolution. A modern TEM often has all the capabilities shown in red.

Scanning Probe Microscopy


Scanning probe microscopy (SPM) covers several related technologies for imaging and measuring surfaces on a fine scale, down to the level of molecules and groups of atoms. At the other end of the scale, a scan may cover a distance of over 100 micrometers in the x and y directions (horizontal plane), or the plane of the surface being imaged, and 4 micrometers in the z direction (vertical plane), or the height of the surface. This range is enormous. SPM technologies share the concept of scanning an extremely sharp tip (3 to 50 nm radius of curvature) across the object surface. The tip is mounted on a flexible cantilever, allowing the tip to follow the surface profile. SPM can now manipulate and probe the electronic structure of individual atoms. It can truly be said that the development of this technology is a major achievement, for it is having profound effects on many areas of science and engineering.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

FIGURE 1.2.2 Looking straight down on a silicon crystal in the direction of the <112> crystal plane, the atoms line up in closely spaced pairs of columns with just 0.78 angstrom between each column in a pair. The dumbbell shape shows that the microscope has achieved better than 0.78 angstrom resolution. With a smaller beam, the rows would be seen as two clearly separated features, but with a larger beam, the pair would blur into one oval-shaped feature. Analysis of the power spectrum shows the presence of information down to a record 0.6 angstrom. The image was obtained using a 300 kV VG Microscope HB603U scanning transmission electron microscope equipped with a Nion aberration corrector, by M. Chisholm, with processing by A. Borisevich and A. Lupini and aberration correction by P. Nellist, N. Dellby, and O. Krivanek, Nion Company. Courtesy of Oak Ridge National Laboratory.

Focused-Ion Beam


The focused-ion beam (FIB) has become an invaluable research tool within the past 10 years. This versatile instrument allows the focusing and rastering of a less than 10 nm ion beam onto a material, with the possibility of directing a scanning electron beam at precisely the same location. Thus, either ion-induced or electron-induced images are possible. The strength of the FIB lies in the ability to use the ion beam to etch away or section through a device to examine its subsurface structure. Moreover, the ion (or electron) beam can locally decompose an organometallic or other complex gas that is bled into the specimen chamber to deposit metals or dielectrics onto the material, thereby building up a nanoscale structure.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

In industry, a major application is in the repair of defects in masks that are used in photolithographic delineation. The FIB tool has also enabled semiconductor manufacturers to identify defective circuits and quickly make a TEM cross section of the device at the defect location to identify the cause, all within a few hours. This capability is now rapidly spreading in TEM laboratories in the United States for the preparation of TEM samples from materials that are notoriously difficult to prepare by more conventional methods. The FIB can actually be used to make device repairs with a process known as circuit edit—that is, by cutting an interconnect that is incorrectly joining two features and building a new interconnect with the use of organometallic gases. Now the FIB is even being used to cut into biological materials (for instance, blood cells), and in conjunction with cold-stage electron microscopy reveals the cytostructure directly. An even more revolutionary capability is to fabricate nanostructures directly with the FIB.


Electron-Beam Writers


In the field of fabrication, electron-beam writers have progressed from 200 nm definition in the 1970s to the current level of 10 nm (see Figure 1.2.3). Similarly, the availability of

FIGURE 1.2.3 Microelectromechanical system mirror arrays such as the optical cross connect (left; single mirror shown right) fabricated at Lucent Technologies have proven to have application to many different technology industries. The ability to tailor the mirror sizes, array dimensions, frequency performance, range of motion, and so on has stimulated research applications in telecommunications, high-definition displays, gene chips manufacture, and even semiconductor circuit production. Fabrication of such components and subsystems requires clean environments and a heavy investment in the tools similar to those found in semiconductor circuit fabrication facilities. Courtesy of Lucent Technologies Bell Labs.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

electron-beam lithography has facilitated the investigation of quantum-size effects by enabling the fabrication of specific device structures. These examples illustrate the emerging trend of using instrumentation to define structures of materials that can then be characterized directly. This trend will quickly become an essential part of experimental sciences at the nanoscale, as the tools themselves are used to fabricate and characterize materials, bringing an enhanced level of understanding to the long-term paradigm in materials research of microstructure-property correlations.


Staffing Trends


The increase in the capabilities and sophistication of instrumentation is placing new demands on the technical and professional staff required to support the instrumentation. For instance, it is not uncommon that a master’s or a Ph.D. degree is a minimum requirement for independently operating secondary ion mass spectrometry or TEM instrumentation in service-oriented companies. Such advanced training is also required in any facility offering analytical services. Such positions might previously have been staffed with personnel having associate degrees or bachelor’s degrees. Industrial companies also require Ph.D.-caliber staff for their own in-house analytical staff, and the demand for skilled, highly trained instrumentation specialists is increasing while the number of domestic Ph.D. students in the physical sciences is steadily decreasing.

a  

P.D. Nellist, M.F. Chisholm, N. Dellby, O.L. Krivanek, M.F. Murfitt, Z.S. Szilagyi, A.R. Lupini, A. Borisevich, W.H. Sides, Jr., and S.J. Pennycook, “Direct Sub-Angstrom Imaging of a Crystal Lattice,” Science 305, 1741 (2004).

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

Education and Outreach

Midsize facilities are central not only to advancing materials research but also to training the next generations of scientists and engineers in materials disciplines at the B.S., M.S., and Ph.D. levels. Maintenance and staffing of facilities are central to the functioning of these facilities in both their research and their training roles. The committee cannot overemphasize the importance of the role that midsize facilities play in the professional training of scientists, technicians, and cross-disciplinary researchers.

Midsize facilities carry out three important roles in the development of undergraduate students, graduate students, and postdoctoral associates:

BOX 1.3
Desktop-Size Synchrotron Radiation Sources

Synchrotron radiation has already revolutionized x-ray science as a consequence of its extremely bright beams and its continuous spectrum. The disciplines taking advantage of this structural analysis tool include structural molecular biology, physics, geology, materials science, semiconductor processing, and molecular environmental science. A disadvantage of synchrotron radiation, however, is that it is primarily available only at a small number of large electron accelerators.

Recently, Lyncean Technologies, Inc., was formed to produce a desktop-size synchrotron source called the Compact Light Source (CLS), which is expected to produce 1 angstrom (Å)) and longer wavelength radiation. Existing synchrotron light sources employ multi-gigaelectronvolt electron beams that are stored in large rings of magnets to generate intense, bright, 1 Å wavelength radiation. The CLS couples an electron beam with a laser beam to accomplish the same effect. The shift from periodic magnets used in a typical synchrotron light source to the laser beam used in the CLS allows a reduction of energy and scale by a factor of more than 200.

Although not as bright as the beam provided by large accelerator-based sources, the radiation that the CLS would provide is considerably more intense than that of the x-ray generators used throughout the world in academic and industrial laboratories. Its wavelength would be tunable, allowing the performance of experiments that cannot be conducted with conventional x-ray generators. A great deal of the research now done at the accelerator-based synchrotron radiation facilities could be performed locally, as the CLS is expected to provide an x-ray beam that can drive up to three end stations at a cost of perhaps less than $5 million. Such local (midsize) facilities would provide experience that would allow more effective use of the larger facilities. Consequently, they would complement the large accelerator-based synchrotron radiation sources. However, demands for this capability will put additional pressure on sources of funding for midscale instrumentation.

These devices will undoubtedly require additional research and development before commercialization. And, while estimates of pricing are in the few-million-dollar range, they do not include the necessary instrumentation to exploit the radiation (e.g., beamlines).

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
  1. Providing access to instruments and techniques that are not available within their advisers’ or their departments’ laboratories;

  2. Introducing techniques outside the scope of their advisers’ expertise; and

  3. Facilitating the introduction of these young scientists to users from different disciplines and/or scientific or technological sectors (e.g., industrial or national laboratories).

Midsize facilities provide a unique educational and training ground for students as well as for senior investigators. Learning new techniques from a practical perspective is a valuable complement to classroom exposure to technology. A

The need for local synchrotron radiation facilities was discussed in the Report of the Basic Energy Sciences Advisory Committee Panel on Department of Energy Synchrotron Radiation Sources and Science. The report stated:

A final, significant note about beamline utilization is that users apparently place great value upon nearby access to synchrotron radiation facilities. In the early years when only SSRL [Stanford Synchrotron Radiation Laboratory] was available, users came from all parts of the country. Increasingly, however, all facilities have become regional facilities, with most of the users from the local region. Even the APS [Advanced Photon Source] has nearly half of its CAT [Collaborative Access Team] members from the state of Illinois. Although several interpretations of this trend are possible, the simplest is to accept that regional facilities, be they 2nd or 3rd generation, appear to be going a long way towards serving the needs of the local user communities. When combined with the increase in demand at all the sources, one is forced into the conclusion that there is great latent demand for regional storage ring facilities in all parts of the country.a

Although the values cited for the Advanced Photon Source user community are quite old (circa 1997; in fact, today less than 25 percent of the users come from Illinois),b the value placed on nearby access to facilities remains the same. The desktop sources discussed here could meet part of that latent demand.

Finally, it is breakthroughs in instrumentation development such as this one that can spur the progress of research—but only if the new tools are distributed, operated, and maintained with care and forethought.

a  

Basic Energy Sciences Advisory Committee, Report of the Basic Energy Sciences Advisory Committee Panel on Department of Energy Synchrotron Radiation Sources and Science, Washington, D.C.: Department of Energy, November 1997, p. 89. Available online at http://www.sc.doe.gov/bes/BESAC/syncpanel.pdf; last accessed June 1, 2005.

b  

Private communication with M. Gibson, Director, Advanced Photon Source, May 2005.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

common situation is for a facility manager or experienced staff scientist to provide training to individuals or to a small group, teaching the uses of instrumentation or the implementation of a new method of using the instruments. The training is usually conducted with samples of research interest to the investigators. Multidisciplinary or cross-sector collaborations2 result from these interactions, broadening the perspectives of the students and increasing the scientific output. As a consequence, they become more valuable additions to the U.S. science and technology workforce.

A common experience at a facility is that a graduate student becomes quite skilled in an advanced technique. The student comes into contact with scientists from other fields—or sectors—who are also experimenting at the facility. The other scientists recognize the value of collaborating with the student. The student recognizes the opportunity to learn about a new problem or field. A collaboration arises that markedly broadens the student’s perspective. The student becomes more confident in his or her skills and better able to adapt to new problems and environments. This type of interaction can happen only if the student obtains hands-on experience and is present at the facility.

Facilities also often fill an important role in promoting public understanding of science. The array of scientific accomplishments, the scale and talent mix of staff members involved, and the remarkable capabilities of modern machines make it both practical and exciting to share effective presentations with the general public, especially with precollege students.

Commercial Activities

By serving as testbeds, expert resources, or simply research and development work space, midsize facilities help invigorate ongoing commercial ventures or even spawn new ones. Industrial collaborators pay fair market prices to use midsize facilities on short-term or even on recurring bases, because they recognize the economy of outsourcing the operations, maintenance, and professional staff overhead that such facilities require.

Finally, one type of facility that warrants specific mention is the commercial analytical service laboratory. These facilities are unlike those at universities and national laboratories, which generally receive their funding directly or indirectly from the federal government, and are unlike those at private corporations, which

2  

For the purposes of this report, the committee defines multidisciplinary and cross-sector collaborations as follows: Multidisciplinary collaborations bring together experts trained in different academic areas to work on a common problem. Cross-sector collaborations bring together researchers from universities, government, and industry.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

are internally funded. Commercial analytical laboratories are generally formed by individuals who contribute personal funds, borrow from a lending institution, or raise equity by selling ownership to others. With these initial capital funds, they purchase equipment, hire personnel, and establish a laboratory to provide characterization services to all who can afford the fees that are needed to cover the true expense of sustaining the facility. All costs such as building rent, personnel budgets, capital equipment purchases, and some profit must be collected as revenue if the commercial laboratory is to operate successfully. Therefore, charges for commercial analytical laboratory services are typically much higher than are those for services from a university or national laboratory facility. A private corporation will also calculate the full cost of its internal facility to determine the cost-effectiveness of these internal facilities. Thus, a corporation may also “outsource” to a commercial laboratory those services not efficiently performed in-house. The long and successful history of the leading commercial analytical laboratories is testimony both to the demand for their services and to their ability to recoup sufficient operating costs so as to be sustainable and profitable.

DEFINITION OF A MIDSIZE FACILITY

Midsize facilities are distinct from small facilities in being large enough to require a dedicated and explicit infrastructure for their sustained success. They are distinct from large facilities in being small enough to be flexible and responsive to the needs of a relatively local user community and in possessing equipment the scale and cost of which allow duplication, when demand merits, in different regions of the nation.

In many ways, midsize facilities fulfill a role complementary to that of the large facilities such as the synchrotron and neutron facilities. While both midsize and large facilities are important to the national scientific endeavor, there are distinct differences in their modes of operation (in addition to the very large differences in their operating budgets). The large facilities provide intensive user time at limited periods during the year. They generally require a proposal and its approval for access requiring advance planning. In contrast, midsize facilities generally provide frequent access to their instrumentation and generally (but not always) do not require a proposal process. Thus, synchrotron users may have access to synchrotron beams three to four times per year or less, while midsize facility users often use the instruments on a weekly or more frequent basis. At many of the midsize facilities, the researchers make use of multiple techniques for their studies—indeed, this is essential in addressing complex materials problems. The very nature of synchrotrons and neutron scattering facilities requires that they serve a large regional or national clientele. In contrast, the midsize facilities serve more local communities, although

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

in many cases they have unique instruments and capabilities that attract users nationally or internationally.

As developed by the committee and used in this report, the following definition of the term “midsize facility” informs the discussion throughout and is reflected in this study’s recommendations:

A midsize facility maintains and operates one or more pieces of equipment at a university or national laboratory and has the following characteristics:

  • Facilitates scientific and/or technological research for multiple users;

  • Provides services on local, regional, or national scales;

  • Is open to all qualified users subject to generally agreed-upon rules of access;

  • Has a resident staff to assist, train, and/or serve users; and

  • Has a replacement capitalization cost of between approximately $1 million and $50 million and an annual operating budget (including staff salaries, overhead, supplies, routine maintenance and upgrades, and so on) in the range from about $100,000 up to several million (2004) dollars.

The committee recognizes that not all midsize facilities meet all elements of this definition.3 It also believes that midsize facilities often distinguish themselves in other ways. A midsize facility frequently meets one or more of the following additional criteria:

  • Provides a unique or special service that is not generally available in an individual investigator’s laboratory;

  • Fulfills a particular scientific or niche need in the research enterprise;

  • Has a clear mission that addresses a well-defined or emerging need of a well-defined community;

  • Plays a leading role in education, workforce training, and workforce development;

  • Facilitates instrument and technology development and/or training;

  • Promotes synergy and communication among its users and with others;

  • Fosters cross-disciplinary and cross-sector interactions, including scientific, medical, and engineering endeavors; and

  • Represents a means for coordinating scientific activities among other facilities or institutions with complementary capabilities.

3  

Indeed, over the summer of 2003 the committee visited a number of facilities that would not qualify as midsize facilities for materials research, and yet they provided valuable information that was relevant to the committee’s charge.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

The committee makes three final important observations:

  1. The committee has clarified its nomenclature since the release of its interim report (Appendix D), in which it used the term “smaller facility” to describe the type of facility that it now calls a midsize facility. The change in terminology is intended to reduce confusion. In conversations with the community, the committee found that the term “smaller facility” was often misinterpreted as describing “small” facilities, such as those maintained and used by only one investigator in his or her private laboratory space. The committee believes that the term “midsize facility” is clearer.

  2. Federal program managers, university administrators, and the media have blurred the distinction between a “center” and a “facility.”4 The committee distinguishes these entities in the following manner:

    • A center is a collection of investigators with a particular research focus.

    • A facility is a collection of instrumentation, equipment, or physical resources that enables investigators to conduct certain activities.

  1. It is also important to distinguish between the instrumentation itself and the facility that supports the instrumentation: that is, a discussion of facilities should not be focused on instrument procurement alone.5 Instruments are sophisticated tools employed by researchers to extend their capabilities. Facilities may contain certain instruments or suites of instruments, but facilities include mechanisms for supporting, operating, and accessing the instrumentation so that research can be performed. Facilities provide the interface between researchers and the sophisticated instrumentation.

Facilities provide sets of tools that expand the capabilities of groups of researchers (examples of the variety of instruments used in materials research are given in Box 1.4). Throughout this report, however, the committee argues that a successful midsize facility must be more than just a collection of equipment: staff, users, operating funds, specialized environments, and a management plan are some of the essential additional ingredients for successful operations.

4  

For instance, the popular Materials Research Science and Engineering Center program of the National Science Foundation supports centers that often contain a “shared experimental facility” element.

5  

A forthcoming report by the National Research Council’s Committee on Advanced Research Instrumentation is expected to address these issues in more detail and in a broader context, including interdisciplinary and interagency perspectives.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

BOX 1.4
The Array of Instruments for Materials Research

Modern scientific instrumentation is rich with acronyms, abbreviations, and complex nomenclature. The field of materials research is no exception. In part because of the breadth of the research enterprise, the suite of tools available to synthesize, fabricate, characterize, measure, and analyze a sample is enormous and can be overwhelming. However, each type of instrument has a specific purpose with special capabilities and special limitations.a Learning to use these tools is as much about actually operating them as it is about learning which tools should be used to achieve which desired outcomes.

Many people are familiar with the optical microscope, but in the modern era, this method of imaging is only one of many, many possibilities. An optical microscope combines two distinct systems: an imaging component that directs photons of visible light at the sample, and a magnification element that allows the user to resolve the finer details of the interactions of the light with the sample. The optical microscope simply provides information about how particles of a certain type (visible light) interact with the sample. Because the human eye is also sensitive to visible light, we usually think of an optical microscope as merely a sophisticated magnifying glass. The key to understanding characterization and measurement instrumentation is to understand how an instrument interacts with the sample and to what types of features it is responsive, that is, what differences in the sample’s properties cause a variation in instrument response.

Almost all characterization and measurement tools involve a process that scatters incident particles (or a beam of particles) off a sample; the result of the particle-sample interaction is analyzed for clues about the sample. For electron microscopes, the incident particle beam is a collimated beam of electrons that can scan across the sample, tunnel through it, or be transmitted. For secondary ion mass spectrometry, particles incident upon a sample eject secondary ions that are analyzed for composition. In various types of x-ray experiments, x-ray photons form the beam of incident “particles.”

As materials research has evolved as a science and engineering discipline, more sophisticated measurements of sample properties have become necessary. Similarly, more sophisticated synthesis, fabrication, and preparation methods have emerged. As shown in Figure 1.4.1, specialized techniques have been developed that concentrate on different features: some techniques focus on imaging alone and offer different resolutions, while others measure concentrations of atoms in bulk and offer different detection sensitivities. As shown in Figure 1.4.2, the different techniques also access different depths of the sample under study.

Following is a list of definitions of the acronyms used in Figures 1.4.1 and 1.4.2:

  • AES Auger electron spectroscopy

  • AFM atomic force microscopy

  • EDS x-ray energy dispersive spectroscopy

  • ESCA electron spectroscopy for chemical analysis

  • μESCA microspot electron spectroscopy for chemical analysis

  • FE-AES field-emission Auger electron spectroscopy

  • FE-SEM field-emission scanning electron microscopy

  • FTIR Fourier transform infrared spectroscopy

  • GC/MS gas chromatography mass spectrometry

  • GDMS glow discharge mass spectrometry

  • RBS Rutherford backscattering

  • SEM scanning electron microscopy

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

FIGURE 1.4.1 Analytical resolution versus detection limit for a variety of standard characterization techniques in materials research. Courtesy of Evans Analytical Group.

FIGURE 1.4.2 Depiction of the depth of sample material that can be analyzed with different materials characterization techniques. Courtesy of Evans Analytical Group.

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
  • SIMS secondary ion mass spectrometry

  • TEM transmission electron microscopy

  • TOF-SIMS time-of-flight secondary ion mass spectrometry

  • TXRF transmission x-ray fluorescence

  • XPS x-ray photoelectron spectroscopy

  • XRF x-ray fluorescence

a  

For more information, the interested reader is referred to the excellent volume C.R. Brundle, C.A. Evans, Jr., and S. Wilson, Encyclopedia of Materials Characterization: Surfaces, Interfaces, and Thin Films, Stoneham, Mass.: Elsevier, 1992.

SCOPE OF THIS STUDY

This study was undertaken to assess the effectiveness of the network of midsize facilities that the federal government supports—fully, or in large part—to enable materials research within the United States, to establish the level of accessibility of the facilities to the broadest possible research community, and to determine how the network could be modified to have maximum impact in a financially constrained era. The formal charge to the committee is provided in Appendix A.

The primary concerns driving this study are the significant opportunities over a wide cross section of scientific disciplines that might be missed because the resources of midsize user facilities are not fully exploited. The capabilities of instruments such as secondary ion mass spectrometers or electron microscopes are rapidly increasing, yet the cost of acquisition and maintenance is escalating to the point that the smaller facilities, typical of individual institutions, can no longer afford their purchase and upkeep. Furthermore, the developments in instrumentation that often take place in midsize facilities underpin critical tools for industry, as, for instance, happened with the focused-ion beam. Likewise, these facilities fill an extremely important role in the education and training of future scientists and engineers by ensuring that students have familiarity with the latest instrumentation and techniques.

This report describes the findings of the NRC’s Committee on Smaller Facilities, which was established by the Solid State Sciences Committee of the Board on Physics and Astronomy. The basic challenge addressed by the committee is framed by the following observations:

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
  1. Instruments critical to materials research are becoming sufficiently expensive that the individual investigator cannot afford them; resources must be pooled to manage these instruments in midsize multiuser facilities.

  2. Midsize facilities are sufficiently sophisticated in structure and content that a complex support network is required to maximize their effectiveness.

ORGANIZATION OF THE REPORT

Chapter 1 defines midsize facilities, outlining the activities carried out at them, and argues that they are more than just collections of instruments—they pool talent, leverage resources, seed cross-disciplinary interactions, and provide research, training, and education services to a broad community.

Chapter 2 describes general features of midsize facilities, characterizes their operations, and illustrates with some examples.

In Chapter 3, the committee reports on its findings concerning the most significant challenges facing midsize facilities. The common thread in these challenges is the struggle to ensure long-term viability—be it in securing stable infrastructure, working within the larger context of other facilities in the region, maintaining a clear mission relevant to users, or cooperating with commercial interests. Because midsize facilities are designed to last longer than one researcher’s short-lived project, their operations require mechanisms to ensure economic stability, qualified staff, regular maintenance, student education, revitalization, and training support that transcend the single-research-project life cycle. Likewise, since these facilities serve more than one research group’s needs, they are additionally challenged to balance the competing demands of many different users.

Chapter 4 characterizes the current investments in midsize facilities and refers to the international context. The absence of a thematic home for the long-term commitments essential to midsize facilities is identified as one area ripe for improvement. The potential advantages (and challenges) of several forms of regional facility networks are also discussed.

Throughout this report, the committee argues that a successful midsize facility must be treated as something more than just a collection of equipment: trained staff, users, long-term infrastructure, and a management plan are some of the essential additional ingredients for successful stewardship. Chapter 5 presents the committee’s findings and observations, conclusions, and recommendations.

At the end of the report are appendixes containing the following: the committee’s statement of task (Appendix A); the agendas for the committee meetings (Appendix B); facsimilies of the two questionnaires, the distribution list, a compilation of the data received, and their analysis (Appendix C); the committee’s interim report of March 2004 to the funding agencies (Appendix D); a sample report

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×

from one of the site visits (Appendix E); a description and some statistics on federal programs that support midsize facilities (Appendix F); a summary of the National Science Foundation Workshop on Chemical Instrumentation held April 16-17, 1999 (Appendix G); a personal perspective from a midsize facility user (Appendix H); and the biographies of committee members and staff (Appendix I).

Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 11
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 12
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 14
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 20
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 22
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 23
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 25
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 26
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 27
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 28
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 29
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 30
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 31
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
Page 32
Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Suggested Citation:"1. Nature and Importance of Midsize Facilities." National Research Council. 2006. Midsize Facilities: The Infrastructure for Materials Research. Washington, DC: The National Academies Press. doi: 10.17226/11336.
×
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Most of the instruments now used for materials research are too complex and expensive for individual investigators to own, operate, and maintain them. Consequently, they have become increasingly consolidated into multi-user, small to midsized research facilities, located at many sites around the country. The proliferation of these facilities, however, has drawn calls for a careful assessment of best principles for their operation. With support from the Department of Energy and the National Science Foundation, the NRC carried out a study to characterize and discuss ways to optimize investments in materials research facility infrastructure with attention to midsize facilities. This report provides an assessment of the nature and importance of mid-sized facilities, their capabilities, challenges they face, current investment, and optimizing their effectiveness.

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