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Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
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Chapter 2

Electronics and Electrical Engineering Laboratory

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

PANEL MEMBERS

V. Thomas Rhyne, Consultant, Austin, Tex., Chair

Ralph K. Cavin III, Semiconductor Research Corporation, Vice Chair

Robert A. Buhrman, Cornell University

Larry A. Coldren, University of California, Santa Barbara

Jack H. Corley, Advanced Technology Institute

James P. Eisenstein, California Institute of Technology

George A. Gomba, IBM Microelectronics

Roger F. Hoyt, IBM Storage Systems Division

Waguih Ishak, Hewlett-Packard Laboratories

Carl O. Jelinek, Raytheon Corporate Systems

Donald B. Keck, Corning, Inc.

Solomon Max, LTX Corporation

Robert C. McDonald, Intel Corporation (retired)

Suzanne R. Nagel, Consultant, Pennington, N.J.

Lori S. Nye, MEMC Electronic Materials, Inc.

Alton D. Patton, Texas A&M University

Ghery S. Pettit, Intel Corporation

Robert E. Rottmayer, Seagate Technologies

Robert E. Schwall, American Superconductor Corporation

Henry I. Smith, Massachusetts Institute of Technology

Carlton E. Speck, Delphi Energy and Engine Management Systems

Peter W. Staecker, Consultant, Lexington, Mass.

John A. Wehrmeyer, Eastman Kodak Company

Submitted for the panel by its Chair, V. Thomas Rhyne, this assessment of the fiscal year 1999 activities of the Electronics and Electrical Engineering Laboratory is based on site visits by individual panel members, a formal meeting of the panel February 11–12, 1999, in Gaithersburg, Md., and documents provided by the laboratory.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

LABORATORY-LEVEL REVIEW

Laboratory Mission

According to laboratory documentation, the mission of the Electronics and Electrical Engineering Laboratory (EEEL) is to promote U.S. economic growth by providing measurement capability of high impact focused primarily on the critical needs of the U.S. electronics and electrical industries and their customers and suppliers.

This mission statement clearly expresses the purpose and goals of the EEEL, and the programs under way in the laboratory are in conformance with the EEEL and NIST missions. The panel was particularly pleased to note an increasing emphasis on cross-laboratory programming, as evidenced by the formation of the Office of Optoelectronics Programs.

The laboratory's mission is broad and encompasses many areas in which work done at NIST has the potential to make a great impact. However, the amount of funding available to EEEL is limited, and choices must be made about how and where scarce resources should be spent. The panel continues to applaud the laboratory's historically verified ability to select specific areas for focused activities with carefully targeted impacts. However, it is important to balance the laboratory's tradition of providing necessary results to a well-defined customer base with the ability to engage in high-risk projects that have the potential for significant payoffs and that will introduce NIST and EEEL to new technical communities.

Technical Merit and Appropriateness of Work

The EEEL continues to produce an outstanding array of excellent projects. These include the electronic kilogram (watt-balance) work in the Electricity Division, the development of NIST Traceable Reference Materials (NTRM) for critical dimension measurements in the Semiconductor Electronics Division, the application of reverberation chamber technology to electromagnetic compatibility (EMC) testing in the Radio-Frequency Technology Division, the production and dissemination of the microcalorimeter energy-dispersive spectrometer (EDS) system in the Electromagnetic Technology Division, and the world-class accuracy of the optical power measurements calibrations services in the Optoelectronics Division. Many other high-quality projects are discussed in detail in the divisional assessments. In addition to continuing efforts on fairly mature projects in which the value to the technical community has already been demonstrated, the laboratory also has begun work in some areas that have the potential to produce significant results in the future. One example is the expansion of the effort on copper interconnects.

Impact of Programs

The EEEL employs a variety of mechanisms to disseminate the technical results of laboratory programs to the relevant scientific and industrial communities. Staff members publish in refereed journals, attend conferences, organize workshops, host guest researchers, and post information on the World Wide Web. EEEL is also very active in the development and production of Standard Reference Materials and Data and in the performance of calibration

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

services. The laboratory's projects affect a varied array of industries, and specific discussions of how individual programs have helped solve particular problems are given in the divisional assessments. One example of the laboratory 's value to a certain industry, semiconductor manufacturers, can be seen in the success of the 1998 International Conference on Characterization and Metrology for ULSI Technology. This workshop, and the resulting publication of the conference proceedings, focused on important measurement techniques for ultralarge-scale integration (ULSI) semiconductor technologies.

Laboratory Resources

Funding sources1 for the Electronics and Electrical Engineering Laboratory (in millions of dollars) are as follows:

 

Fiscal Year 1998

Fiscal Year 1999 (estimated)

NIST-STRS, excluding Competence

31.5

33.1

Competence

2.2

2.0

ATP

2.1

1.1

Measurement Services (SRM production)

0.1

0.1

OA/NFG/CRADA

10.2

11.8

Other Reimbursable

2.9

2.9

Total

49.0

51.0

As of January 1999, staffing for the Electronics and Electrical Engineering Laboratory included 270 full-time permanent positions, of which 229 were for technical professionals. There were also 29 nonpermanent and supplemental personnel, such as postdoctoral research associates and part-time workers. Despite budgetary pressures, the laboratory continues to maintain an impressive array of highly qualified personnel owing mainly to the attractive working environment available at NIST.

Over the past year, there have been two significant leadership transitions, as the directors of the Office of Microelectronics Programs (OMP) and of the EEEL itself both retired. The panel is very pleased to report that the transitions to new management have gone smoothly. In addition, the Radio-Frequency Technology Division (formerly known as the Electromagnetic

1  

The NIST Measurement and Standards Laboratories funding comes from a variety of sources. The laboratories receive appropriations from Congress, known as Scientific and Technical Research and Services (STRS) funding. Competence funding also comes from NIST's congressional appropriations, but it is allotted by the NIST director's office in multiyear grants for projects that advance NIST's capabilities in new and emerging areas of measurement science. Advanced Technology Program (ATP) funding reflects support from NIST's ATP for work done at the NIST laboratories in collaboration with or in support of ATP projects. Funding to support production of Standard Reference Materials (SRMs) is tied to the use of such products and is classified as Measurement Services. NIST laboratories also receive funding through grants or contracts from other government agencies (OA), from nonfederal governmental (NFG) agencies, and from industry in the form of Cooperative Research and Development Agreements (CRADAs). All other laboratory funding, including that from Calibration Services, is grouped under Other Reimbursable.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

Fields Division) underwent significant reorganization, and the result is an effective refocusing of division projects on the key technical needs of the relevant industrial communities.

The panel continues to be concerned about the quality of the facilities available to the EEEL staff. Fundamental issues such as poor air quality and the absence of basic building maintenance make it difficult for personnel to perform the research and service functions that are vital to fulfilling the EEEL mission. Although the planned construction of the Advanced Measurement Laboratory is a positive step, occupation of this new facility is still many years off and will not address the need for facilities improvements in Boulder. Interim solutions are needed. Plans to provide funding for new and replacement equipment are also very important, as aging or inappropriate equipment will negatively affect the quality of the work produced in the laboratory.

DIVISIONAL REVIEWS

Electricity Division
Division Mission

According to division documentation, the mission of the Electricity Division is to provide the world's most technically advanced and fundamentally sound basis for all electrical measurements in the United States by realizing the International System (SI) of electrical units; developing improved measurement methods and calibration services; and supporting the measurements and standards infrastructure needed by U.S. industry to develop new products, ensure quality, and compete economically in the world's markets.

The Electricity Division has an appropriate mission statement that is consistent with the diverse array of projects under way. The division follows a well-documented process for selecting and terminating projects in furtherance of the defined mission. Industry roadmaps, such as those produced by the National Electronics Manufacturing Initiative and the Industry Applications Society of the Institute of Electrical and Electronics Engineers (IEEE), seem to be utilized effectively in guiding project selection. In the electric power area, where an industry-established roadmap is not available, the division has successfully created and employed its own roadmap.

Technical Merit and Appropriateness of Work

The Electricity Division projects are of uniformly high technical merit and are clearly advancing the state of the art in the specific areas identified in the division mission. The panel noted several particularly successful high-impact projects. The Fundamental Electrical Measurements Group is improving the watt-balance, which is designed to monitor the kilogram in terms of electrical units. The Electronic Instrumentation and Metrology Group is working on measurement and calibration services for thermal converters that link alternating current quantities to direct current standards for voltage and current using cryogenic techniques. The Electrical Systems Group is developing technologies related to optical current transducers for high-voltage measurements and in situ monitoring, as well as working on a possible laboratory

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

standard. This project is an excellent example of the benefits of collaboration between various divisions and with industrial partners. Finally, the division as a whole is improving its customer service through the development of the Information System to Support Calibrations (ISSC), a Web-accessible database for tracking calibration services and results.

The core mission of the Electricity Division has been the development, maintenance, and dissemination of basic electrical units, standards, and measurement technologies, including written standards. At the same time the division has pursued a vigorous research agenda in systems-oriented projects such as the work on Electronic Data Exchange by the Electronics Information Technologies Group and the development of Testing Strategies Software in the Electronic Instrumentation and Metrology Group. Industry activity, interest, and need in the systems area are increasing; and the division, and indeed the laboratory, may want to consider raising the number of systems-oriented projects. The panel believes that matrix management of such projects is usually the best approach for effectively coordinating the diverse talents required to advance systems-oriented projects. Therefore, the division might consider developing a strategy for identifying more systems-oriented projects and a mechanism for managing and staffing such projects.

Impact of Programs

The Electricity Division is very influential in the development of important written standards and application guides both nationally and internationally, as staff members are active in 32 IEEE committees and 14 International Electrotechnical Commission (IEC) or International Organization for Standardization committees.

The division also effectively disseminates project results through technical journal publications, conference attendance, and committee activities. However, the division currently makes only minimal use of the World Wide Web. This shortcoming should be remedied as soon as possible by making the division Web pages much more user-friendly and by assembling a more comprehensive collection of information on the site, such as links to division publications and detailed technical information. In addition to providing more complete and up-to-date information to the public, the division could also better utilize the Web to enhance its services related to proprietary information. For example, the ISSC has the potential to be a valuable resource for the division's customers while simultaneously simplifying staff-customer interactions, but until effective security (e.g., a firewall) is installed on the division's network, the calibration information cannot be made available to the customers.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Division Resources

Funding sources for the Electricity Division (in millions of dollars) are as follows:

 

Fiscal Year 1998

Fiscal Year 1999 (estimated)

NIST-STRS, excluding Competence

7.8

7.9

Competence

1.1

1.0

ATP

0.3

0.1

OA/NFG/CRADA

1.5

2.0

Other Reimbursable

1.1

1.1

Total

11.8

12.1

As of January 1999, staffing for the Electricity Division included 65 full-time permanent positions, of which 59 were for technical professionals. There were also 11 nonpermanent and supplemental personnel, such as postdoctoral research associates and part-time workers.

Division personnel resources are stretched very thin; often there is only one key person assigned to a project. This single-point coverage places many projects in jeopardy. The lack of personnel resources also seems to impede the development of new projects and initiatives.

The panel recommends that the division and the laboratory immediately implement appropriate computer network security firewalls. The present lack of firewalls is an unacceptable and unnecessary risk to customers ' proprietary data and to NIST's own proprietary information. The absence of a firewall also appears to be a barrier to full deployment of certain project results and innovations, such as the calibration tracking system.

The recent extended power failure had near-catastrophic consequences for various projects, apparently because backup power arrangements were not adequate to maintain temperature-regulated environments. A careful assessment of infrastructure failure risk should be made.

The Video Technology project staff in the Electronics Information Technologies Group is looking for components for a high-definition television (HDTV) system on which to develop appropriate test patterns to evaluate HDTV compression algorithms. Funding is needed to allow this group to upgrade its hardware to maintain leadership in generating standards for HDTV and National Television Systems Committee television.

The Electricity Division is leading the NIST-wide effort on SIMnet, an Internet-based system intended to assist in disseminating information on calibration techniques throughout the Western Hemisphere. The current commercial technologies for voice and video communication on the Internet are not necessarily robust enough to facilitate these international interactions, and perhaps it would be advisable to rely on still images and voice communication until the Internet bandwidth is in place.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Semiconductor Electronics Division
Division Mission

According to division documentation, the mission of the Semiconductor Electronics Division is to provide technical leadership in research and development of the semiconductor measurement infrastructure essential to silicon and other advanced semiconductor technology needs.

This mission statement is concise and appropriate, and the division 's programs are in conformance with the mission, as well as with the overall EEEL and NIST mission statements. Through its involvement with National Technology Roadmap for Semiconductors (NTRS) activities and associated working groups, the Semiconductor Electronics Division has identified the industry needs to which the unique capabilities of this division can be applied most effectively.

The panel commends the division for its extensive interactions with individual companies, industry organizations, and professional groups; these activities enable the development of a research agenda responsive to the needs of industry. Active participation in industry roadmapping and standards activities has also been used effectively by the division and by the Office of Microelectronics Programs to prioritize and establish programs with the highest potential impact. The fruits of this effort are evident in the crispness of the division's strategic objectives as outlined in the EEEL strategic plan and in the match between the programs under way and these strategic goals. The panel believes that the new effort to develop systematic prioritization processes for project selection should assist in the allocation of scarce resources.

Reiteration by division and laboratory management that they expect NIST work to be at the “Best in the World” level is seen by the panel to be an admirable goal that provides appropriate motivation and recognition for the staff.

Technical Merit and Appropriateness of Work

A broad array of activities is currently under way in the Semiconductor Electronics Division. The balance of work between silicon and compound semiconductors accurately reflects the relative magnitude and importance of these two technologies in the marketplace. Most of the projects are targeted toward very specific industrial needs, although the panel did observe a few examples of excellent basic research. The panel believes that to prepare for long-term NTRS needs and emerging technologies, more effort needs to be directed towards fundamental science projects. NIST has a potentially important role to play in the advancement of the understanding of fundamental properties of nanostructures and their measurement. NIST's leadership in this area, along with industry and university cooperation, will enable the United States to maintain its position as a technical world leader in semiconductors.

There are four groups in the Semiconductor Electronics Division: Integrated Circuit (IC) Technology, Device Technology, Thin Film Metrology, and Materials Technology. Specific observations about the work performed in each of these groups during the past year are given below. This division is also heavily involved in the work of the Office of Microelectronics Programs, a matrix management approach to the coordination of NIST's efforts in support of the

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

National Semiconductor Metrology Program. This office is reviewed in a separate section at the end of this chapter.

In the IC Technology Group, three programs are in progress. In the work on Metrology for Process and Tool Control, the objectives include the development of NIST-traceable reference materials for critical dimension (CD), step height, and overlay metrology. This internationally unique effort provides CD reference materials below 0.5 µm, micromachined tool-induced shift extractors, edge detectors for overlay-shift management, and micromachined standard wafer chip carriers compatible with 200 mm metrology systems. The CD reference material provides in situ traceability to atomic-level lattice plane spacing with the use of high-resolution transmission electron microscopy. This work has enabled understanding of the relationship between electrical and physical measurements and has the potential to allow seamless scaling of the standard down to 0.1 µm geometries. Having a consistent CD standard throughout the world should greatly assist the semiconductor industry by resolving technical controversies. Staff in this area have also developed unique test structures that will allow users to determine if a CD line shift is a result of a tool-induced shift or wafer-induced shift.

The Microelectromechanical Systems (MEMS) project involves significant cross-disciplinary activity within NIST and utilizes a number of graduate student interns and visiting scientists. Using a complementary metal oxide semiconductor (CMOS)-compatible MEMS process, IC test structures are being fabricated for the measurement of mechanical stress in interconnects, for the dynamic measurement of bond pad temperatures, and for the characterization of signal propagation in interconnects. This program is unique in its focus on the use of MEMS technology for IC test structures. Competence-building projects include the invention of a new convection-based accelerometer and application of microfluidic MEMS technology to develop a microlaboratory on a chip.

The work on Dielectric and Interconnect Reliability Metrology is preparing NIST to meet the future measurement needs of the semiconductor industry. Last year's assessment indicated some concern regarding the division's work on alternate gate dielectrics and copper interconnect. This year, the panel is pleased to applaud a concerted effort by the division to expand and upgrade its work in this area. Currently, there are indications that as gate dielectric thicknesses, driven by scaling of transistor features, approach 2 nm, the reliability of the transistor gate oxide will degrade. Moreover, existing tests are no longer able to predict gate oxide integrity at these dimensions. The NIST program has developed new techniques to extract reliability parameters for gate oxides from highly accelerated stress tests. NIST is proactively working with the Joint Electronic Devices Engineering Council/American Society for Testing and Materials (ASTM) to develop new measurement standards for ultrathin silicon dioxide gates. These new standards are of utmost importance to continuation of device scaling. In the interconnect area, the increasing use of copper for IC interconnects has heightened the need for reliability prediction techniques. A project in this group focuses on the evaluation of failure mechanisms resulting from adhesion failure between two dielectrics in an interconnect stack, chemical-mechanical polishing-induced defects in the metal barriers, and electro/stress migration phenomena. Designs for single-level and via-type structures that characterize electromigration in aluminum and copper interconnects have been incorporated into the NIST 36 Test Chip. In cooperation with industry, the first versions of these chips are being fabricated using copper interconnect.

In the Device Technology Group, the main focus is on Metrology for Simulation and Computer-Aided Design. This project addresses the industry need for validated models and simulators for semiconductor devices, for processes, and for thermal and electrical interconnects

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

for packages. The NIST Insulated Gate Bipolar Transistor model and parameter extraction procedures are recognized as the de facto international standard for this device. The procedures now include physically based predictive mechanisms for device failures, which are complemented by a nondestructive reliability test mechanism. The package modeling effort encompasses interconnect models for electromagnetic interference studies and the development of compact package thermal libraries. Future work is focused on extending modeling and validation standards to the CMOS structures needed by NTRS and on emerging device designs through the Compact Model Council. The NTRS is predicting significant scaling of junction depth to less than 200 Å, and NIST needs to anticipate the industry need for more accurate modeling and physical validation to support this direction. The Semiconductor Electronics Division is in the unique position of being able to understand the fundamental physics, which may be limiting current methods, and to provide direction on the most accurate methods for device optimization.

In the Thin Film Metrology Group, work focuses on ellipsometry, a widely used technique to measure film thicknesses (in situ and ex situ) that appears to be extendable for future generations of IC devices. Staff in this group have developed an SRM that is NIST-traceable down to 4.5 nm and have worked cooperatively with a company, VLSI Standards, to arrange commercial production and marketing of these standards. However, this testing protocol does not appear to be adequate for future reference material needs, and projects are under way to develop new standards. In particular, there is a need to have optical modeling and testing directly correlate with physical and electrical measurements. There is also a need for in situ process control measurements. A 1998 NIST-organized workshop provided industry guidance on future dielectric measurement and standardization needs.

The last group in the Semiconductor Electronics Division, the Materials Technology Group, oversees work on three programs. In the Optical Metrology for Semiconductor Manufacturing project, new Fourier transform infrared (FTIR) spectroscopy methodology and modeling have been developed to improve the accuracy of optical constants by an order of magnitude. This advance enabled an improvement in the measurement accuracy for oxygen in silicon wafers by an order of magnitude and helped to identify an error source in oxygen metrology in annealed 300 mm silicon wafers. Future work, based on the improved optical constants, is directed toward the need stated in the NTRS for accurate oxygen measurement in heavily doped silicon. Also, the deleterious effect of H-surfactant used during SiGe growth has been demonstrated.

The focus of the effort in Metrology for Compound Semiconductor Manufacturing is to develop in situ metrology characterization techniques that enable the cost-effective manufacturing of compound semiconductor devices. Unique activities within this group include publication of the first quantitative results on InGaAs composition during molecular beam epitaxy (MBE) growth using a novel in situ x-ray probe. An in situ diffuse reflectance spectroscopy capability has been implemented that provides direct feedback control of the MBE growth, with a goal of predictably yielding high-quality devices. In this same spirit, an x-ray standing wave technique was demonstrated that can be used to measure strain and interface quality of buried InGaAs layers. In an effort to promote Hall measurements for industrial applications and provide a data analysis service, an interactive Web site is being developed that could serve as a model for other NIST metrology services.

Finally, the scanning-probe microscopy metrology effort provides a unique-in-the-world two-dimensional capability to extract carrier profiles from scanning capacitance microscopy

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

(SCM) images of p-n junctions in silicon. This effort is critically important, since modeling and simulation of the performance of future generation devices ultimately depend on the quality of the physical data available. A compact code, designated as FASTC2D, has been written to extract doping profiles from SCM data and will be made available to industry. It appears that the spatial resolution (10 nm) via SCM techniques is capable of meeting requirements of precision and resolution for current generation devices, but continued effort will be needed to achieve the 10-30 Å resolution that the NTRS predicts will be necessary for future device generations.

Impact of Programs

One of the main ways in which the Semiconductor Electronics Division affects industry is by providing tools that support the measurement infrastructure of the semiconductor industry. Such tools include SRMs, test chips, standard reference data, and software. In addition to development of these products, division personnel visit industrial sites, host a variety of visitors, and make available tutorial material on an as-needed basis. They also are active in conference activities —an excellent example is the “1998 International Conference on Characterization and Metrology for ULSI Technology,” which was organized by NIST in cooperation with several industry consortia and was held at the NIST Gaithersburg site. Overall, the panel saw substantial evidence that NIST receives and is responsive to many hundreds of special requests for assistance from industry each year. An indication of the strength of this division 's relationships with industry and with other national laboratories is that these institutions are now supporting some of NIST's processing needs for work on standards.

In general, the panel believes that the preferred method of standards dissemination by the Semiconductor Electronics Division is for companies to implement NIST standards as commercial products. There are several examples of this approach, which allows the division to redirect its resources away from routine production activities and toward emerging metrology issues. The panel recommends that the commercialization of division-derived standards be adopted as the regular protocol for standards distribution. A related issue is NIST's need to make a careful assessment of the trade-offs involved in patenting its methods and standards. Among the benefits of patent protection are the maintenance of traceability for industry users and the motivations of commercial suppliers to produce reference materials and manufacture analytical instrumentation. In specific cases, these benefits are so great that NIST should consider applying for selected foreign patents.

The Semiconductor Electronics Division has made substantial contributions to peer-reviewed professional publications, to conferences and workshops, and to the production of high-quality NIST technical reports. Although the division does use the Web to provide easy access to project descriptions, the panel recommends increased use of the Web to disseminate standards, methodologies, and tutorials. Access to such materials by process development engineers and by factory personnel will increase the reach of EEEL into a broader user community and will enhance industry participation. An example of how use of the Web can facilitate dissemination is the noteworthy new initiative from the Materials Technology Group that plans to provide an interactive Web site for Hall measurement applications.

Participation of NIST personnel in standards committees is of significant value to the semiconductor industry. NIST is universally viewed as an neutral arbiter, and division staff have high credibility on metrology-related issues. On international committees, NIST's participation

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

plays a key role in the promotion of technologies that enable international trade. NIST's international credibility is based on the high level of respect for NIST's historical culture of precise and accurate metrology, as evidenced by the fact that many Japanese semiconductor industries turn to NIST for standards. The expansion of NIST's purview in concert with technological expansion is important to U.S. industrial strength, and therefore the panel encourages an expansion of NIST 's international role as one element of the growing international character of U.S. industry and trade.

Division Resources

Funding sources for the Semiconductor Electronics Division (in millions of dollars) are as follows:

 

Fiscal Year 1998

Fiscal Year 1999 (estimated)

NIST-STRS, excluding Competence

7.4

7.5

Competence

0.3

0.1

ATP

0.6

0.5

OA/NFG/CRADA

0.2

0.9

Other Reimbursable

0.1

0.1

Total

8.6

9.1

As of January 1999, staffing for the Semiconductor Electronics Division included 45 full-time permanent positions, of which 38 were for technical professionals. There were also five nonpermanent and supplemental personnel, such as postdoctoral research associates and part-time workers.

The quality of personnel is very high, and morale is good. Several staff members were recognized by external awards over the past year. The most impressive of these was the receipt by a NIST staff member of the first European Packaging Award for outstanding achievements in the development of wire bonding. The selection committee was composed entirely of Europeans, which makes the accomplishment even more remarkable.

The panel commends the division for its active and successful recruitment of senior technical specialists from industry. These people facilitate the effective interaction of the division with industry.

The panel notes with pleasure that funding appears to be likely for the construction of the new Advanced Measurement Laboratory on the NIST campus. The state-of-the-art capabilities of this facility are essential to support the NIST work needed to fulfill the exacting future metrology needs identified by the semiconductor industry.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Radio-Frequency Technology Division
Division Mission

According to division documentation, the mission of the Radio-Frequency Technology Division is to enhance industrial competitiveness by providing national metrology resources for the measurement of the electromagnetic properties of components, materials, systems, and environments throughout the radio spectrum.

The panel believes that this mission statement is clear and appropriately supports the EEEL and NIST missions. The core mission of NIST is to provide the ultimate in measurement calibration standards in the United States, where all other calibrations are said to be “traceable to NIST standards.” This traceability is a critical element in U.S. industries' ability to compete in the worldwide marketplace, and therefore new and existing measurement programs in the Radio-Frequency Technology Division are vital to this core mission. For example, this division's calibrations, including microwave electrical measurements, new transfer standards for radio-frequency (RF) power measurement, antenna measurements, and anechoic chamber certifications, comprise approximately 20 percent of the calibration services performed at NIST.

Within the past year, this division has changed its name from Electromagnetic Fields to Radio-Frequency Technology and reorganized the group structure within the division. These changes were designed to refocus the activities of the division to be more closely aligned with the stated mission and with the needs of the division's customers and funding agencies. Interactions of the Radio-Frequency Technology Division with other NIST divisions, with other government laboratories, and with the industrial community as a whole, appear to be increasing. The reorganization also seems to be motivating the staff to participate in appropriate as well as career-enhancing research in areas related to the mission, and the new structure may stimulate more productive collaborations between the various disciplines represented in this division. In addition, the panel is pleased to note that the division staff were very responsive to the comments made in last year's assessment and were able to highlight progress made in a number of areas.

Technical Merit and Appropriateness of Work

The Radio-Frequency Technology Division continues to decrease its dependence on Department of Defense funding and to increase its focus on commercial needs, such as those of the telecommunications and wireless industries. Frequent contact with industry leaders is a valuable tool for maintaining a commercial focus. To insure that relevant NIST results reach new customers, division management is putting standard procedures in place for disseminating information to industry.

In the reorganization, the Microwave Metrology Group became the Radio-Frequency Electronics Group, and this group has many projects under way. Staff members continue to provide a variety of core measurement services in power, impedance, voltage, and noise, as well as transfer standards over the frequency range of 10 kHz to 110 GHz. Unfortunately, staff attrition in these areas has limited technical progress and decreased the efficiency of services. A study of techniques of measurement automation might reveal some alternatives to the traditionally labor-intensive approach to these activities. Nevertheless, design innovation continues in some areas, such as power sensor bandwidth extension. These advances benefit the

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

user community and demonstrate the staff's strength in engineering. The work on international harmonization of power standards in the waveguide bands WR22, WR15, and WR10 is progressing nicely.

Beyond this historically important work in measurements and standards services, the Radio-Frequency Electronics Group manages several other projects in a variety of fields. The Network Analysis and Measurements project continues to provide needed support for traceability of microwave vector measurements within the microwave and millimeter-wave community. The Noise Standards and Measurements project covers two traditional areas, connectorized noise temperature measurements between 1 and 75 GHz and amplifier noise figure measurements between 1 and 18 GHz, and one newer field, development of on-wafer noise measurement methods. Central to this work is the development of a new noise-figure radiometer, which has the capability to measure one-port noise temperature or amplifier noise figure and may provide measurements significantly faster than existing radiometers.

The Electromagnetic Properties of Materials project is applying innovative analytical and measurement techniques to traditional and new challenges in bulk and thin film electronics materials. Recent improvements to measurement technology include the in situ monolithic microwave integrated circuit (MMIC) transmission line method for microelectronic thin films and substrates; resonator methods for printed wiring board laminates; ferroelectric measurements for frequency agile devices; and microwave surface resistance and dielectric properties of high-temperature superconducting substrates, single crystals, and composites. The High-Speed Microelectronics Metrology project, through the NIST Industrial MMIC Consortium, provides innovative, appropriate, and timely support to the microwave and millimeter-wave government and commercial community in metrology and software for on-wafer characterization, characterization procedures for electronic packaging, high-speed tests of digital IC, electromagnetic characterization of electronic thin films, and uncertainty analysis methods. Finally, the Nonlinear Device Characterization project is a new program designed to enhance NIST expertise and industrial collaboration in new and general measurements for active nonlinear devices, measurement assurance for passive nonlinear component characterization, refinement of time-domain network analysis techniques, methods for characterization of high-speed digital circuits, and development and identification of a useful set of parameters for describing nonlinear devices.

The Radio-Frequency Fields Group was formed this year through the merger of the Antennas and Materials Metrology and the Fields and Interference Groups, and several projects are under way in this newly titled group. The Emission and Immunity Metrology project's reverberation chamber research is a topic of much interest to U.S. industry. Companies in aerospace, computers, motor vehicles, medicine, consumer electronics, and communications/radar have annual sales on the order of half a trillion dollars, and these firms allocate up to 10 percent of their product development cost to electromagnetic compatibility (EMC) testing. Reverberation chamber work demonstrates the potential for quick, accurate, and inexpensive testing of whole products for immunity to RF emissions. For example, trial validation testing of entire vehicles has been completed in 2 weeks, as compared with the 3 months necessary when current IEC test methods are used. With advances made by division staff in the electromagnetic modeling and statistics of these chambers, NIST remains on the leading edge of the application of reverberation chamber technology to EMC testing. Another potential use of these facilities is for emissions measurements. However, significant work will be required to allow correlation between the results obtained from present measurement

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
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techniques and those obtained in reverberation chambers in order for standards writing and regulatory bodies to adopt such chambers. NIST should be at the forefront of these investigations, as it is important to facilitate the transition of these techniques from industry acceptance to industry standards status within the next 2 years.

In the Antenna Measurement Theory and Application project, development of planar and nonplanar near-field measurement techniques continues to be of interest to both government and industry. These techniques will be extended to 110 GHz by 2002, and the division's strategic plan calls for eventually providing metrology measurement service up to 500 GHz. Thermal imaging and holographic methods for rapid antenna measurement are being developed to lower the cost of antenna characterization.

Additionally, a comprehensive effort by the Metrology for Antenna, Radar Cross Section (RCS) and Space Systems project is directed at RCS antenna chamber certification and antenna measurement procedures. Both government and industrial customers will benefit by initiatives in developing metrology for wireless communication systems, microwave metrology applicable to earth stations, metrology for RCS measurements, and uncertainty analysis of chamber error sources.

Outside the group structure, the division has initiated an exploratory program, the National Wireless Electronic Systems Testbed (N-WEST). The N-WEST consortium is designed to improve U.S. competitiveness by facilitating industry consensus leading to standards on issues surrounding wideband millimeter-wave communications. This project is fairly young, but for its progress and value to be measured effectively in the future, its direction and goals should be clearly defined.

Overall, the panel finds that the programs under way in the Radio-Frequency Technology Division are appropriate, and the planning process appears to follow the published EEEL guidelines. However, the panel noted that most projects showed few goals beyond the year 2000. Planning horizons should be extended to 5 years, especially for large construction projects and facilities. Information to determine these longer-term goals should be taken from the results of the NIST Workshop on Microwave Technology, held in October 1998. This approach to gathering information on the community's goals and needs should be extended to regular meetings that would optimize the value to both NIST and its government and commercial customers.

Impact of Programs

The overall effect of the Radio-Frequency Technology Division programs on industry and on the Department of Defense is both appropriate and positive. Direct collaborations with commercial and government customers on calibration programs have resulted in immediate and obvious impacts, with near-field scanning techniques developed at NIST now being used in over 100 facilities worldwide. The NIST MMIC Consortium responds to near-term industrial partner needs and generates standards for wider industry use in the long term. Other examples of key high-impact activities in this division include reverberation chamber research in collaboration with the automotive and aerospace industries; the NIST biannual short course on near-field measurement techniques; RCS standards and range certification activities with the Department of Defense and industry; calibration services in antennas, network analysis, noise, and microwave power, including production of Standard Reference Materials; and public release of software for

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
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enhanced network analysis methods allowing inexpensive measurements with common laboratory instruments.

In last year's report the panel noted that substantial delays existed in the publication of the EMC workshop results. This year, it appears that this problem is being addressed by management. However, another concern from last year's report, the inefficient use of the World Wide Web by this division, is still an issue. The Web site list of the division's publications needs to be updated, as it currently lists papers only up to 1996. In addition, these documents should be electronically downloadable (e.g., in portable document format [pdf]).

Finally, in areas of potential future impact, the division is considering increased involvement in EMC standards writing. The panel encourages this step, as a variety of test methods are being promulgated worldwide in support of a range of different views on metrology issues. NIST personnel can make substantial contributions in this complicated area.

Division Resources

Funding sources for the Radio-Frequency Technology Division (in millions of dollars) are as follows:

 

Fiscal Year 1998

Fiscal Year 1999 (estimated)

NIST-STRS, excluding Competence

5.2

5.9

Competence

0.3

0.4

ATP

0.2

0.0

OA/NFG/CRADA

2.0

1.7

Other Reimbursable

1.3

1.3

Total

9.0

9.3

As of January 1999, staffing for the Radio-Frequency Technology Division included 56 full-time permanent positions, of which 50 were for technical professionals. There was also one nonpermanent or supplemental person, either a postdoctoral research associate or a part-time worker.

Programs are progressing well despite a 10 percent reduction in the number of staff over the past 3 years. Pressure to produce more results with less support can be expected to adversely affect efficiency and morale, and further reductions in staff will have a negative impact on the division's ability to meet the metrology needs of industry and the Department of Defense. One way to help maintain the current staff level is for management to develop plans and earmark funds for training, mentoring, and retaining key personnel.

The division is to be commended for a variety of completed and planned facility upgrades at the Boulder site. A new (but temporary) surface for the existing ground screen in the open-area test site facility has been installed. A permanent stainless steel ground plane is needed to make the quality of the NIST facility comparable with that of similar facilities in the United States and around the world. The new temporary surface may only be a short-term fix as local RF interference sources will increasingly compromise the effectiveness of the site. The panel strongly advises the division to use the neighboring NIST-owned RF quiet zone for these

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

measurements in the future. Absorber material in the near-field facility has been upgraded to meet fire safety regulations. In addition, renovation of the heating, ventilation, and air-conditioning system in this facility is scheduled, and the upgrade will allow the temperature control necessary to perform accurate millimeter-wave measurements. A new anechoic chamber is nearly finished; staff only awaits the receipt and installation of a state-of-the-art remote positioning capability. A new roof for Wing 6 is planned. This repair should end the disastrous flooding in the noise laboratory due to roof leaks during rainstorms. The improvements in the physical plant are having a positive impact on staff morale, and the resulting increases in NIST technical capabilities will enable the division to fulfill its future programmatic goals. The panel was concerned, however, to note that certain pieces of key equipment on some calibration efforts were of an age where continued support and repair by the manufacturer is questionable. Such equipment should be replaced.

Electromagnetic Technology Division
Division Mission

According to division documentation, the mission of the Electromagnetic Technology Division is to develop and promote advanced standards and measurement methods for the magnetics, electronics, and superconductor industries and their scientific communities; to employ phenomena based on magnetics, superconductivity, and cryoelectronics to create new standards, apparatus, and measurement technology; to advance the state of the art by basic research and development of requisite materials, fabrication techniques, and metrology; to provide new measurements, instrumentation, imaging and characterization tools, and standards in support of the magnetics industry; to develop measurement technology to determine basic properties of magnetic materials and structures with support from theoretical studies and modeling; to collaborate with the magnetic recording industry in development of metrology to support future recording heads and media with their ever-increasing data density; to use the unique properties of superconductors to invent and improve measurement methods for electromagnetic signals ranging from static voltages and magnetic fields to audio, microwave, infrared, visible, and x-ray frequencies; to lead the international community in setting standards for measurement of superconductor parameters; and to provide the metrology infrastructure needed for the industrial development of superconductors, both large and small scale.

The EEEL and NIST missions focus on economic growth through the impact of metrology on high technology. The connection between these missions and the division's mission should be clarified to ensure proper focus of the limited resources available to the Electromagnetic Technology Division. In addition, both laboratory and division management could benefit from greater familiarity with the needs of the magnetic recording industry. For example, many measurements in magnetics may require precision of only two or three significant figures in order to have key economic impacts.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
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Technical Merit and Appropriateness of Work

The Electromagnetic Technology Division is pursuing technically challenging research in highly innovative metrology, advanced nonconventional electronics, and sensor technologies. Success in obtaining funding from outside agencies for several projects in superconducting electronics and sensors is a strong external indicator of the division's strength and of its reputation for quality work. This effort is effective in keeping NIST fully cognizant of cutting-edge developments and needs as they evolve. It also positions NIST to make substantial contributions to advancing these fields.

The Electromagnetic Technology Division carries out programs in three areas: Superconductor Wire Measurements and Standards, National Electrical Standards and Superconducting Electronics, and Magnetic Data Storage. The panel was impressed by the quality of the technical work in progress and wishes to highlight several of the division's recent accomplishments.

The development of measurement methods being carried out in the Superconductor Standards and Technology project continues to produce high-quality results of significant value to industry. In this area, division staff are working on methods and apparatus whose development is beyond the capabilities of most individual businesses. Cooperation with industry and the dissemination of results appears to be going well. Last year the panel was concerned that the level of effort devoted to involvement with the superconductor standards activities of the IEC was below that required for a truly effective program. However, in the past year, more than 60 percent of U.S. participants in the superconductor-related technical advisory groups of the United States National Committee have terminated their membership, and NIST's lack of funding for these sorts of standards activities seems only to be symptomatic of a more widespread problem throughout U.S. industry, where overall support for standards work is declining. Another issue from last year's report was the panel's concern that the division was allowing too much staff time to be consumed by “job shop” work for industry. This year, the panel was pleased to observe that critical current measurement capabilities are being efficiently transitioned to industry, thereby freeing the staff to devote their time to more mission-focused, technology-advancing work.

The Superconductor Interfaces and Electrical Transport project continues to provide international industries with the definitive work in the area of stress effects on commercial superconductors. The project has been effective in adjusting its focus to maintain attention on those issues of greatest technical concern, as demonstrated by continued external funding for this work. The ongoing effort by NIST staff to author a book capturing the experience of this group seems to be going well.

The nanoscale cryoelectronics effort has matured nicely over the past year. In two applications, the quantum capacitance standard and the microcalorimeter energy-dispersive spectrometer (EDS) system, the focus has shifted from development of the superconducting devices to resolution of the global systems issues associated with the applications themselves. The capacitance standard has actually progressed faster than the panel anticipated. The division plans to compare this device with the calculable capacitor and to integrate this new approach into the NIST electrical standards infrastructure. This activity presents the opportunity for a very fruitful collaboration between the Electromagnetic Technology Division and the Electricity Division. As in the use of Josephson junction technology for voltage standards, the quantum

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

capacitance device has the potential to change the way capacitance standards are maintained worldwide.

The microcalorimeter EDS system is clearly ready to be transitioned to industry, and the division is working diligently on this process. This technology is of obvious value to the entire microelectronics industry, and acceleration of this commercialization effort should have a high priority within EEEL. The application of microcalorimetry to mass spectrometry appears quite promising, and the panel applauds the innovative and cost-effective way in which the division has obtained the equipment necessary for this project. The work would benefit from the hiring of personnel with expertise in macromolecular mass spectrometry, perhaps through the addition of a temporary employee, such as a postdoctoral student or a contractor.

The division's efforts in the still-nascent field of superconducting electronics and in sensors and detectors are quite solid and, in several instances, Best in the World. The programmable Josephson array project has been a major success, and further improvements continue. The development effort on the pulse programmable array is a very interesting approach and is showing good progress. Overall the Josephson circuit work remains an essential and highly successful component of NIST's leadership position in fundamental standards. In addition, this work makes important contributions to the field of specialized digital electronics and detectors, which remains a technically challenging area of long-term economic potential.

The high-temperature thin film microwave electronics work and the associated effort in tunable ferroelectrics is a strong program that positions NIST to make significant contributions in an area undergoing rapid technological change for which improved materials and new measurement techniques will clearly be needed. The non-Josephson junction work on high-performance sensors and detectors is also pushing the state of the art in device fabrication. This work can generally be characterized as very solid and in some instances, such as the vanadium dioxide bolometer work, highly innovative.

The division's work on fundamental switching time in head and disk materials of importance to the storage industry is outstanding. The data will form the basis for understanding performance limits of current technology and support avenues for future materials progress. The projects on magnetic recording metrology are also of good quality. Initial results indicate there may be more opportunities in this field to expand NIST activities, such as potential work on future head geometry focusing on key measurements for head and disk magnetics and work on interface measurements across system, drive, and component manufacturers. The current projects on magnetoresistive memory, nanoprobe imaging, and magnetic materials are on par with worldwide research efforts in other industry, academic, and government laboratories, although a path defining the technology applications for the nanoprobe work is needed to assure future success of the project.

The panel found that the array of projects under way in magnetics is appropriate and is meeting some, but not all, of the industry 's needs. The magnetics storage industry has critical needs in tools and calibration for magnetic layer thickness stochiometry, disk surface finish, disk magnetic defect detection, nanometer-level thickness control of layers in giant magnetoresistant head processing, head fly height, recession, and crown and etch depth control. These areas are not currently addressed by the work under way in EEEL. Although the laboratory has begun to move to address the challenges facing the magnetics industry, the panel believes that this shift in focus could be accelerated and that the strategic plans for the division round-robin measurements in magnetics are in need of crisper definition.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

A possible approach to strengthening NIST's work in magnetics would be to broaden the charter of the Office of Microelectronics Programs to include data storage. With the recent announcement of the 1-inch disk drive, industry is creating magnetic storage devices that are physically smaller than many microprocessors. Since the Internet depends on storage as well as on communications and processing, the potential impact of NIST programs that advance magnetic technologies is quite large. Expansion of the Office of Microelectronics Programs (OMP) would provide a structure under which the key technologists in physics and electronics could work together to solve the interdisciplinary problems in magnetic data storage.

Impact of Programs

The division's work in cryoelectronics, superconducting devices, and sensors is widely and effectively disseminated, and NIST staff play leadership roles in this field through a variety of activities in professional societies and on technical committees. Results in magnetics have been presented at industry and academic consortia meetings, at conferences on magnetism, and in refereed engineering and physics journals on magnetics. Interlaboratory comparison studies are scheduled to be disseminated using similar mechanisms. The high-speed switching studies will form the foundation for critical future measurements, as indicated by the enthusiasm for this work among external industry and academic scientists. The effect of the interlaboratory comparisons is yet to be seen.

The division maintains a Web site, but the content of the posted pages could be expanded to provide a more thorough and useful description of the work under way in this division.

Division Resources

Funding sources for the Electromagnetic Technology Division (in millions of dollars) are as follows:

 

Fiscal Year 1998

Fiscal Year 1999 (estimated)

NIST-STRS, excluding Competence

4.4

4.7

Competence

0.5

0.5

ATP

0.8

0.2

OA/NFG/CRADA

2.1

3.4

Other Reimbursable

0.1

0.1

Total

7.9

8.9

As of January 1999, staffing for the Electromagnetic Technology Division included 38 full-time permanent positions, of which 34 were for technical professionals. There were also five nonpermanent and supplemental personnel, such as postdoctoral research associates and part-time workers.

Expertise in experimental physics is the predominant skill set among division staff, and management should consider how to maintain a balance of expertise in other key areas, such as

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

theory and electrical engineering. The division also needs to develop a strategy for funding the project in magnetic recording metrology.

The division needs to address the question of funding for the upcoming move of equipment and personnel into the new laboratory space. This transition will cause a serious short-term disruption to several of the programs, but in the long term, this change, particularly the renovated and enlarged clean room, should have a major positive impact on the programs. It is regrettable that expenses associated with the clean room have had an impact on the division's equipment budget, as new equipment, such as steppers, is needed to enable the maximum use of the new facility. Budgeting for the costs associated with the move (utilities, supplies, and so on) should be addressed in a manner that does not unduly affect the division's overall program. Other areas of concern to the panel include the forthcoming need for substantial capital equipment replacement in the microlithography area in a year or so, and the possible need for future upgrades in processing equipment for micro- and nanoelectromechanical systems.

Optoelectronics Division
Division Mission

According to division documentation, the mission of the Optoelectronics Division is to provide the optoelectronics industry and its suppliers and customers with comprehensive and technically advanced measurement capabilities, standards, and traceability to those standards.

The division mission is well stated and succinct and fits logically and completely within the overall NIST and EEEL missions. However, this industry is currently growing at a rate of 15 to 20 percent per year, so it will be increasingly difficult for the division to provide comprehensive measurements and standards, as stated in the mission. Without significant growth in the level of effort, the programs will have to become increasingly focused on a few key areas in order to respond to industry's needs in a timely fashion.

The newly created Office of Optoelectronics Programs is an excellent response to the panel's previous recommendations. The panel was delighted to learn that leadership for this new office has been found within the current Optoelectronics Division and that efforts to coordinate optoelectronics activities across EEEL and NIST have begun. Alignment of the wide variety of optoelectronics activities could increase the effectiveness of such programs throughout NIST and enhance NIST 's ability to participate in international standards activities in this area. Already, NIST is striving to achieve greater intra- and intergroup collaborations, and there is positive evidence that the effort has resulted in enhanced outputs in optoelectronics. However, establishing the Office of Optoelectronics Programs as a line item in the budget is a key step that has not yet been completed.

The division's work with the Optoelectronics Industry Development Association (OIDA) was highlighted in last year's report. The resulting Metrology Roadmap has been published, and the panel looks forward to observing how the division will implement the recommendations laid out in this document.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Technical Merit and Appropriateness of Work

The panel continues to regard the work of the Optoelectronics Division as world class in several areas. The activities of the division are managed within four technical groups—Sources and Detectors, Fiber and Integrated Optics, Optical Components, and Optoelectronics Manufacturing —each of which runs two projects.

The Laser Radiometry project continues to provide well-established calibration services to industry for laser power and energy meters and detectors, as well as optical fiber power meters and detectors. Although the output of this project provides a small source of additional revenues for the division, its execution also consumes a nontrivial amount of resources. Ongoing efforts to improve spectral responsivity, laser power and energy calibrations, optical power accuracy, and automated beam profile measurements are all appropriate goals for advancing the quality and range of NIST's calibration services in this area. In particular, the power measurement accuracy has improved from ±2 percent to ±1 percent at 248 nm. The group's work to obtain power measurements at 193 nm is also noteworthy, since this wavelength is vital to the photolithography community. This past year, an international comparison was held for the calibration services performed by this group, and NIST's measurement accuracy was determined to be world class.

Progress continues on the High-Speed Optoelectronic Measurements project. In the past year, NIST staff used their state-of-the-art heterodyne capability to calibrate photonic devices for eight different companies.

The staff on the Optical Fiber Metrology project continue to provide industry with valuable SRMs for optical fiber coating diameter, fiber cladding diameter, pin gauge standard for ferrules, optical fiber ferrule geometry, polarization mode dispersion (PMD), and chromatic dispersion standards. In the past year, this group has demonstrated a significant number of new capabilities. The work done on fiber mode field diameter is extremely timely for the industry. This effort is also valuable, and the panel is pleased that an SRM may be forthcoming. The nondestructive technique for measuring the zero-dispersion wavelength uses an innovative method based on four-wave mixing. However, the panel cautions that in addition to the wavelength zero, the slope of the dispersion curve will be required. The recently begun measurements in erbium-doped fiber amplifier (EDFA) gain and noise are a positive first step towards determining sources of measurement uncertainty. This work will become increasingly important to the industry. The work on multimode differential mode delay frequency domains is unique, and the technique employed at NIST has shown the industry the usefulness of offsetting laser sources by 17 µm in order to obtain higher multimode fiber system bandwidth performance. This group also sponsors the biannual Symposium for Optical Fiber Measurements, which provides an excellent global forum in this important field.

In the Integrated Optics Metrology project characterization effort, the panel was particularly impressed by the demonstration of measurement of the refractive index profile for planar optical devices using the refractive near-field technique to 4 ×10-5. Efforts along these lines should continue, with an emphasis on improving this level to the order of 10-6. The panel also continues to support this group's use of optical low-coherence interferometry (OLCI) measurements and the responsiveness to industry's need for EDFA measurements.

In the Fiber and Discrete Components project, staff continue to look for new materials that can serve as standards for key emerging wavelengths such as 1300 or ~1450 nm. Work on polarization-dependent loss is building new and important capabilities, and a candidate for a

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

standard is emerging. Strong efforts on photoinduced Bragg gratings include the study of the fundamental material properties using solid-state nuclear magnetic resonance (NMR). The basic understanding of these high-silica materials is important for both Bragg gratings and photolithography stepper lenses. This group produces SRMs that provide wavelength calibration reference lines in the 1510 to 1540 and the 1530 to 1560 nm regions. In the past year, the work on the hydrogen cyanide SRM, the wavelength reference absorption cell for the latter range, has been completed, and fabrication of these units is being performed by an outside organization, a very appropriate move. These SRMs will be particularly useful in light of the increasing installations of wavelength division-multiplexing optical communication systems.

In the Optical Fiber Sensors project, the staff is building capability in OLCI, which can be applied in a number of different areas, most notably the measurement of the group delay in photoinduced Bragg gratings. As the system bit rate increases, the industry will need to examine the group delay in various optical components, and eventually standards will have to be established. In other work, this group used the OLCI technique to uncover a potential problem in high-current sensors, where the presence of high voltages affects the measurement of current. However, it was also determined that the effect can be mitigated by careful orientation of the polarizers. The continuing work in optical data storage metrology is coupled to industry needs and is beginning to achieve important measurement results. The first round-robin measurements on optical disk retardance are highlighting important industry issues. The group has identified significant sources of measurement error and is working toward a retardance SRM. The panel applauds this new initiative, which was established last year based on industry input.

Overall, the Optoelectronic Manufacturing Group, which contains the division's work on semiconductor and dielectric materials and devices, has continued to improve its contacts with customers through round-robin and OIDA workshops. Development of low-cost manufacturing techniques remains a key enabler for the U.S. optoelectronics industry, so the potential impact of NIST's work in this area is significant. Nevertheless, selection of appropriate projects designed for specific impacts on the industry continues to be a challenge for this group. Perhaps a tighter focus on fewer projects would be advisable, with an emphasis on metrology and the development of Standard Reference Data and Materials.

The Semiconductor and Dielectric Materials and Devices projects aim to refine measurement techniques to determine compound semiconductor composition and thickness and to measure purities of source materials, properties of III-V native oxides, and parameters of gallium nitride (GaN)-based materials. The panel supports these goals and the plans to enhance work in these areas. Work on tunable lasers and efficient detectors also can be valuable, provided such components are not available commercially. On the other hand, the work on periodically poled lithium niobate should continue to be phased out. In all cases, this group should continue to make effective use of collaborations inside and outside NIST. For example, obtaining GaN samples from university and industry collaborators seems to be an effective plan for the near term. However, as the market develops for GaN-based components, a materials growth capability at NIST may be advisable to maintain a leading-edge effort. The present activities on molecular beam epitaxy-based growth and associated work on in situ characterization continues to be of some concern to the panel because nearly all optoelectronic components are currently manufactured by metallo-organic chemical vapor deposition (MOCVD) growth techniques. Thus, in situ characterization techniques specific to MBE should not be emphasized. However, creating generic structures that are neither specific to MBE nor available commercially may be a good way to use the existing facility for a variety of materials

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

and device studies. However, if work on III-V growth technology for the manufacture of optoelectronic components is to expand, the acquisition of an MOCVD machine should be investigated.

Overall, the Optoelectronics Division contains a broad array of projects with a variety of goals and customers. Perhaps in the future, the panel could be presented with a portfolio analysis that divides the projects into the major areas of NIST competencies in order to clarify the context of the division's efforts.

Industrial Impact

The Optoelectronics Division has an excellent record of publications and other documentation of its results and is increasingly using the World Wide Web to disseminate information. The division sponsors several very important workshops that attract critical industrial participants and has diverse participation in appropriate standards groups. The association with the OIDA and the resulting joint Metrology Roadmap provide an important link to industry and should further improve the program priorities, effectiveness, and metrology leadership role of the division.

Source and detector measurement services are at the core of the division 's mission and comprise a very visible and effective component of the division's activity. The photolithography community will benefit from NIST's new detector capability at 193 nm and from the recent improvements in accuracy. Other areas where the panel expects the division's work to have positive industrial impact include index profiling of planar waveguides, the native oxide refractive-index work, the compound-semiconductor composition round-robin, and the optical disk round-robin. Projects with longer-term potential include wavelength standards for long wavelength optical communications and the polarization-dependent loss technique.

Division Resources

Funding sources for the Optoelectronics Division (in millions of dollars) are as follows:

 

Fiscal Year 1998

Fiscal Year 1999 (estimated)

NIST-STRS, excluding Competence

5.6

6.0

ATP

0.2

0.3

Measurement Services (SRM production)

0.1

0.1

OA/NFG/CRADA

1.2

1.1

Other Reimbursable

0.3

0.3

Total

7.4

7.8

As of January 1999, staffing for the Optoelectronics Division included 37 full-time permanent positions, of which 33 were for technical professionals. There were also six

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

nonpermanent and supplemental personnel, such as postdoctoral research associates and part-time workers.

The panel continues to be concerned that the ratio of scientists to projects is small and that the number of contract workers employed by the division is high. These factors could result in the division being compromised in key areas of expertise. Another ongoing issue is the low quality of the laboratory space and equipment available to division staff. As National Oceanic and Atmospheric Administration (NOAA) staff vacate space in Boulder, the division is trying to consolidate its laboratories in order to enhance teamwork and communication.

Office of Microelectronics Programs

According to laboratory documentation, the mission of the Office of Microelectronics Programs is to matrix-manage NIST technical activities in support of the silicon semiconductor industry and its infrastructure and to assist NIST management and staff to plan, execute, and deliver results of technical work to semiconductor industry participants.

The OMP carries out this mission by administering the NIST-wide National Semiconductor Metrology Program (NSMP) in support of metrology developments related to the NTRS. Currently, the OMP is coordinating 38 projects across 6 NIST laboratories: the EEEL, the Manufacturing Engineering Laboratory, the Chemical Science and Technology Laboratory, the Physics Laboratory, the Materials Science and Engineering Laboratory, and the Building and Fire Research Laboratory. At least 10 of these projects involve personnel from more than one NIST division, indicating that the OMP fosters excellent cross-disciplinary teaming within NIST. Overall, the panel finds that the varied array of projects are of high technical quality and are appropriately responsive to the needs articulated in the NTRS.

In addition to the technical requirements spelled out in the NTRS, other industry groups provide input to NIST about industry's concerns and future needs. In 1999, the Semiconductor Research Corporation 's Executive Technical Advisory Board identified metrology as the highest priority area of technological need for the semiconductor industry. Particular areas identified included microscopy for chemical deposition, defect detection and inspection/review, film thickness measurement for gate dielectric and patterned barrier layers, two-and three-dimensional dopant profile spatial resolution, and oxygen content in heavily doped silicon. The panel notes that the OMP programs are very well aligned with the metrology needs articulated by the Semiconductor Research Corporation's Board.

Fiscal year 1998 funding for the operation of the OMP totaled $0.9 million, all from STRS, and the total 1998 NSMP funding administered by OMP across NIST was $10.3 million. For fiscal year 1999, the OMP operation STRS funding is estimated to be $1.1 million, and the NSMP funding is estimated to be $12.1 million. As of January 1999, the office had a paid staff of four, three of whom were technical professionals. There was also one part-time guest worker.

Office of Law Enforcement Standards

According to laboratory documentation, the mission of the Office of Law Enforcement Standards (OLES) is to apply science and technology to the needs of the criminal justice community, including law enforcement, corrections, forensic science, and the fire service.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×

The work of OLES continues to be well focused on its mission to support standards in the justice and law enforcement communities. This mission is appropriate for a unit within NIST, although in the past it has not been clear that this office belonged within the EEEL. However, this year the panel observed that the interactions between OLES and EEEL management seem to be effective and that the laboratory leadership is very supportive of the OLES programs and missions. Since OLES is thriving, the panel is not recommending making any organizational shifts at this time. OLES appears to be a major national resource for meeting the standardization needs of the law enforcement community.

Fiscal year 1998 funding for the OLES consisted of $4.9 million from the National Institute of Justice and $0.16 million from other agencies, such as the National Highway Traffic Safety Administration. For fiscal year 1999, the funding estimates are $4.7 million from the National Institute of Justice and $0.17 million from other agencies. As of January 1999, the office had a paid staff of nine, seven of whom were technical professionals.

The importance of this office's work and the customers' satisfaction with the outputs of OLES programs is evidenced by the significant increases in funding received from the U.S. Department of Justice. With these external resources, OLES seems to be providing strong support to the law enforcement community in a number of key areas. In the past, the panel has been somewhat concerned about staffing for the OLES projects, but this issue has been appropriately addressed by the hiring of two new highly qualified people within the past year.

MAJOR OBSERVATIONS

The panel presents the following major observations.

  • The Electronics and Electrical Engineering Laboratory (EEEL) activities continue to produce important results and to have significant impact on relevant industries.

  • The leadership transitions at the laboratory level and in the Office of Microelectronics Programs have gone smoothly. The reorganization of the Radio-Frequency Technology Division appears to have resulted in better alignment of NIST resources to current technical needs with minimal disruption to ongoing activities.

  • Basic facilities issues such as poor air quality and a lack of funding for equipment replacement and maintenance can be expected to make it difficult for staff to efficiently perform high-quality work.

  • The panel is pleased by the formation of the Office of Optoelectronics Programs to coordinate optoelectronics work throughout NIST. An important next step is establishing this office as a line item in the budget.

Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 11
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 12
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 13
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 14
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 15
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 16
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 17
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 18
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 19
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 20
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 21
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 22
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 23
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 24
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 25
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 26
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 27
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 28
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 29
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 30
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 31
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 32
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 33
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 34
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 35
Suggested Citation:"Chapter 2 Electronics and Electrical Engineering Laboratory." National Research Council. 1999. An Assessment of the National Institute of Standards and Technology Measurement and Standards Laboratories: Fiscal Year 1999. Washington, DC: The National Academies Press. doi: 10.17226/9685.
×
Page 36
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