NBSIR 87-3589

Center for Electronics and

Electrical Engineering

Technical

Progress

Bulletin

Covering Center Programs,

January to March 1987,

with 1987 CEEE Events Calendar

July 1987

U.S. Department of Commerce

National Bureau of Standards

National Engineering Laboratory

Gaithersburg, Maryland 20899
INTRODUCTION TO JULY 1987 ISSUE OF THE CEEE TECHNICAL PROGRESS BULLETIN

This is the eighteenth issue of a quarterly publication providing information on the

technical work of the National Bureau of Standards Center for Electronics and Electrical Engineering. This issue of the CEEE Technical Progress Bulletin covers the

first quarter of calendar year 1987.

Organization of Bulletin : This issue contains abstracts for all Center papers re- leased for publication by NBS in the quarter and citations and abstracts for Center

papers published in the quarter. Entries are arranged by technical topic as identified in the table of contents and alphabetically by first author under each subheading within each topic. Unpublished papers appear under the subheading "Released for

Publication". Papers published in the quarter appear under the subheading "Recently

Published". Following each abstract is the name and telephone number of the individual to contact for more information on the topic (usually the first author) . This

issue also includes a calendar of Center conferences and workshops planned for calendar year 1 987, some preliminary announcements for calendar year 1 988, ancl a list of

sponsors of the work.

Center for Electronics and Electrical Engineering : Center programs provide national

reference standards, measurement methods, supporting theory and data, and traceability to national standards.

The metrological products of these programs aid economic growth by promoting equity

and efficiency in the marketplace, by removing metrological barriers to improved

productivity and innovation, by increasing U. S. competitiveness in international

markets through facilitation of compliance with international agreements, and by

providing technical bases for the development of voluntary standards for domestic and

international trade. These metrological products also aid in the development of

rational regulatory policy and promote efficient functioning of technical programs of

the Government.

The work of the Center is divided into two major programs: the Semiconductor Technology Program, carried out by the Semiconductor Electronics Division in Gaithersburg, MD, and the Signals and Systems Metrology Program, carried out by the Electrosystems Division in Gaithersburg and the Electromagnetic Fields and Electromagnetic

Technology Divisions in Boulder, CO. Key contacts in the Center are given on the

back cover; readers are encouraged to contact any of these individuals for further

information. To request a subscription or for more information on the Bulletin , write to CEEE Technical Progress Bulletin, National Bureau of Standards, Metrology

Building, Room B-358, Gaithersburg, MD 20899 or call (301) 975-2220.

Center sponsors ; The Center Programs are sponsored by the National Bureau of Standards and a number of other organizations, in both the Federal and private sectors;

these are identified on page 22.

Note on Publication Lists : Guides to earlier as well as recent work are the publication lists covering the work of each division. These lists are revised and reissued

on an approximately annual basis and are available from the originating division.

The current set is identified in the Additional Information section, page 19.
CEEE Technical Progress Bulletin - July 1987 Page 1

TABLE OF CONTENTS

INTRODUCTION inside front cover

SEMICONDUCTOR TECHNOLOGY PROGRAM

Silicon Materials 2

Gallium Arsenide Materials 2 Dimensional Metrology 3

Integrated Circuit Test Structures 4

Device Physics and Modeling 4

FAST SIGNAL ACQUISITION, PROCESSING, & TRANSMISSION 5

Waveform Metrology 5

Cryoelectronic Metrology 8

Antenna Metrology 9

Noise Metrology 10

Microwave and Millimeter-Wave Metrology 10

Optical Fiber Metrology 11

Electro-Optic Metrology ....11

Other Fast Signal Topics 12

ELECTRICAL SYSTEMS 13

Power Systems Metrology 13

Superconductors .13

Magnetic Materials and Measurements 15

ELECTROMAGNETIC INTERFERENCE 15

Radiated Electromagnetic Interference 15

ADDITIONAL INFORMATION 19

1987 CEEE CALENDAR 19

SPONSOR LIST 2 2

KEY CONTACTS IN CENTER, CENTER ORGANIZATION back cover
Page 2 CEEE Technical Progress Bulletin - July 1987

SEMICONDUCTOR TECHNOLOGY

Silicon Materials

Recently Published

Ehrstein, J. R. , Spreading Resistance

Measurements — An Overview, Emerging

Semiconductor Technology, ASTM STP 960,

D.C. Gupta and P.H. Langer, eds., pp.

453-479 (American Society for Testing

and Materials, 1987),

Spreading resistance is the most versatile electrical technique for characterizing depth profiles in silicon. However, it is being increasingly challenged as an analytical method by

shrinking device geometries. Consequently, refinement of such aspects as probe conditioning, sample preparation

and bevel angle measurement is needed,

and traditional practice regarding calibration, algorithms and profile interpretation must be reexamined. Based on

examples drawn from the author's work,

multi laboratory experiments, and recent

literature to illustrate and discuss

these topics, this paper will attempt to

summarize the current status of the

measurement and its interpretation showing both strong points and apparent

limitations.

[Contact: James R. Ehrstein, (301)

975-2060]

Gladden, W. K. , and Baghdadi, A., Free

Carrier Absorption and Interstitial

Oxygen Measurements, Emerging

Semiconductor Technology, ASTM STP 960,

D.C. Gupta and P.H. Langer, eds., pp.

353-364 (American Society for Testing

and Materials, 1987).

The infrared (IR) absorption of both n- and p-type silicon samples were measured

over the concentration range ~10 15 cm3

to 10 17 cm-3 . The free carrier absorption exhibited a power-law dependence

with wavenumber. The data were fit to a logarithmic function with this dependence, and these results were applied to

the determination of the baseline from

which to compute the corrected net IR

absorption at 1107 cm-1 due to interstitial oxygen. Application of this

correction for the free carrier absorption results in an improvement of 3%-30%

in the accuracy of the oxygen content

determination at concentrations above

1

0

1

6

atoms/cm 3

. [Contact: Aslan Baghdadi, (301)

975-2062]

Gallium Arsenide Materials

Recently Published

Bouldin, C.E., Forman, R.A., and Bell,

M.I., Conversion Yield EXAFS Measurements of Ion-Damaged GaAs , Physics

Review B, Vol. 35, No. 3, pp. 1429-1432

(15 January 1987).

Extended x-ray absorption fine structure

(EXAFS) measurements of ion- implanted

GaAs have been made using conversion

electron detection. This total electron

yield detection technique (termed

CEEXAFS ) allows near-surface sensitivity

with a sampling depth of 700 to 1000 A.

Measurements of the Ga absorption edge

show that implantation of 10 16 cm-2 of

Zn ions at 180 KeV into GaAs produces

heavy lattice damage (amorphization) to

a depth of about 700 to 900 A. After

rapid thermal annealing, the amorphous

layer is found to be recrystallized and

structurally indistinguishable from

unimplanted material. The sampling

depth of CEEXAFS has been measured for

the first time, using standards with

known depth dependent structure. The

CEEXAFS technique greatly reduces Bragg

peak contamination of the EXAFS signal

from single crystal materials, and allows measurement of a variety of samples

which cannot be fabricated as thin layers for conventional transmission or fluorescence EXAFS measurements. The

method permits examination of the local

environment of host atoms (in this case

Ga) in the near surface region without

interference from the underlying bulk

and without the distortions found in

fluorescence EXAFS measurements of con- centrated samples.

[Contact: Charles E. Bouldin, (301)

975-2046]
CEEE Technical Progress Bulletin - July 1987 Page 3 Dimensional Metrology

Recently Published

Larrabee, R.D., Submicrometer Optical

and SEM Linewidth Metrology, Proceedings of the 1987 Measurement Science

Conference, Irvine, California, January

29-30, 1987, pp. V-D ( 1

) -V—D (10).

The feature sizes on modern integrated

circuits are presently taxing the ability of visible-light optical systems to

perform the necessary dimensional measurements required during their production. With the shrinking of feature

dimensions to the micrometer and submicrometer level, diffraction and finite

wavelength become the limitations of

existing optical systems. In an effort

to overcome these limitations, metrology

systems based on the scanning electron

microscope (SEM) have appeared and are often assumed to be the panacea of all

the problems and the limitations of

existing optical systems. In response

to the application of the SEM to these

problems, new optical systems have appeared including ultraviolet and laser

scanning systems. This paper takes a critical look at the basic optical and

SEM metrologies, outlines the program at

the National Bureau of Standards to

provide micrometer and submicrometer

feature-size standards for both technologies, and discusses what can be done in

practice until suitable standards become

available.

[Contact: Robert D. Larrabee, (301)

975-2298]

Larrabee, R.D. , Submicrometer Optical

Linewidth Metrology, to be published

in the Proceedings of SPIE - The

International Society for Optical

Engineering, P.0. Box 20, Bellingham,

WA 98227 [conference Santa Clara,

California, March 1-6, 1987].

The National Bureau of Standards (NBS)

has had a continuing program to develop

optical linewidth standards for the

integrated circuit industry for over 1

0

years. The past work has concentrated

on the development and the certification

of photomask linewidth and pitch

standards. The recent work is directed

at extending the feature sizes on these

standards to cover the range from 0.5 to

30 ym, and at doubling the certification

accuracy to 0.025 ym. Features with

heights larger than approximately 1/4

the wavelength of the illuminating light

cannot be modeled as zero- thickness

layers as is done for photomasks. The

development of models to handle this

thick-layer case and to develop

practical edge-detection criteria are currently under development at NBS.

However, at the present time, it is

generally not possible to interpret the

image profiles of thick features and

thereby measure an accurate linewidth.

The basic obstacles that must be

overcome to achieve accurate submicron

feature size measurements for these

features are reviewed, and the prospects

for future NBS optical standards for

features such as photoresist lines on silicon wafers are assessed. Some

suggestions about what to do until these

standards become available are given.

[Contact: Robert D. Larrabee, (301)

975-2298]

Nyyssonen, D. , A Practical Method for

Edge Detection and Focusing for Linewidth Measurements on Wafers,

Optical Engineering, Vol. 26, No. 1,

pp. 081-085 (January 1987).

Lack of precision and accuracy of inprocess critical dimension (CD) measurements of linewidth continues to be a serious problem at micrometer and submicrometer dimensions. Even with highly

repeatable optical linewidth measurement

systems, variable "offsets" or errors

have been shown to occur with changes in

process variables such as thickness of

the patterned layer and sublayers and

changes in the indices of refraction of

the materials. All of these variations

result in a change in the optical phase

difference that occurs on reflection at

the line edge and, therefore, result in

changes in the structure of the optical

image. Although an accurate coherent
Page 4 CEEE Technical Progress Bulletin - July 1987

Dimensional Metrology (cont'd.)

optical edge-detection method has been

developed, it requires accurate knowledge of this phase difference, which is

not always possible in CD measurements.

This paper proposes a new dual- threshold

method for edge detection and focusing,

based on image theory, which can be

adapted to most optical microscope based

measurement systems. It does not re- quire knowledge of the phase discontinuity at the line edge. The accuracy of

this criterion is compared to two more

widely used criteria, (1 ) the minimum

and (2) 50% threshold, and it is concluded that, when the phase difference

is unknown and varies with normal processing, the new dual- threshold method

is the superior method.

[Contact: Robert L. Larrabee, (301)

975-2298]

Postek, M.T • , Submicrometer Dimensional Metrology in the Scanning Electron

Microscope, to be published in the

Proceedings of SPIE - The International

Society for Optical Engineering, P.0.

Box 20, Bellingham, WA 98227 [conference Santa Clara, California, March

1-6, 1987].

The National Bureau of Standards has

initiated a program to develop scanning

electron microscope linewidth measurement standards for the integrated circuit community. This program involves

the development of: a scanning electron

microscope-based linewidth measurement

and standard reference material certification instrument, the necessary electron beam /sample interaction modeling,

and the appropriate micrometer and submicrometer artifacts. The basic problems that must be overcome to achieve

accurate submicrometer feature size

measurements in the scanning electron

microscope for these artifacts are

reviewed and some suggestions of what

can be done to "bridge- the-gap" until

such standards become available are

given.

[Contact: Michael T. Postek, (301)

975-2299]

Integrated Circuit Test Structures

Released for Publication

Cresswell, M.W., Pessell, N. , Betsch,

R.J., Linholm, L.W. , and Radack, D. J.

,

Sob-Micron Lithography Characterization

Using an Expert System, to be published in the Proceedings of SPIE - The

International Society for Optical

Engineering, P.0. Box 20, Bellingham,

WA 98227 [conference Santa Clara,

California, March 1-6, 1987].

This paper describes a test .chip, test

results, rule generation techniques, and

an expert system for characterizing the

performance of a sub-micron lithography

process. Examples of test results, data

reduction techniques, and expert system

output are given. The objective of this

work is to develop a system for automatic process diagnosis.

[Contact: Loren W. Linholm, (301)

975-2052]

Device Physics and Modeling

Released for Publication

Kim, J.S., The Effect of the Gate

Oxide Thickness on the Speed of MCS

Integrated Circuits.

A simple analysis is presented for the

effect of the gate oxide thickness on

the circuit speed in a short-channel

CMOS/inverter delay circuit. The present

analysis is performed within the

first-order theory of the MOS

transistor. The result of the analysis

shows that an optimum value of the gate

oxide thickness exists, beyond which a further scaling of the gate oxide will

not improve but degrade the circuit

speed. The circuit speed corresponding

to this optimum oxide thickness is the

ultimate upper limit theoretically

possible in a given MOS integrated

circuit. The optimum value of the gate

oxide thickness, to a first-order

approximation, is proportional to the

channel width W, but it is independent

of the channel length L. In particular,
CEEE Technical Progress Bulletin - July 1987 Page 5

Device Physics & Modeling (cont'd.)

for wide channel devices, this optimum

value exceeds the 5-nm to 30-nm range,

which is of practical significance in

the design and processing of advanced

VLSI circuits. At the optimum oxide

thickness, the square-root of the net

propagation delay is the sum of two

components: the square-root of a purely

parasitic component and the square-root

of a device-dependent component.

[Contact: Jin S. Kim, (301) 975-2238]

Recently Published

Albers, J. , Monte Carlo Calculation of

Primary Kinematic Knock-On in SIMS,

Emerging Semiconductor Technology, ASTM

STP 960, D.C. Gupta and P.H. Langer,

eds., pp. 535-557 (American Society for

Testing and Materials, 1987).

Secondary Ion Mass Spectrometry (SIMS)

occupies a central position in atomic

profiling of semiconductor device structures. One of the possibilities for

distortion of the profiles is the phenomenon of knock-on, in which the incident sputtering ion transfers enough

kinetic energy to the impurity atoms to

push them deeper into the material before they can be sputtered and counted.

The effects of sputtering and primary

kinematic knock-on are investigated by

means of a Monte Carlo code previously

used to study ion implantation processes. In particular, the dependence of

the primary kinematic knock-on on the

mass and energy of the sputtering ion as well as the mass of the impurity atom

are presented.

[Contact: John Albers, (301) 975-2075]

Albers, J. , Some Aspects of Spreading

Resistance Profile Analysis, Emerging

Semiconductor Technology, ASTM STP 960,

D.C. Gupta and P.H. Langer, eds., pp.

480-501 (American - Society for Testing

and Materials, 1987).

The calculation of resistivity profiles

(and carrier density profiles) from

spreading resistance requires the use of

a correction factor. The present status

of the calculation of the correction

factor based upon the Schumann and

Gardner multilayer solution of Laplace's

equation is reviewed and discussed.

Recent calculations of carrier densities

from atomic densities are also discussed. In particular, the numerical

solutions of the semiconductor equations

are reviewed, and their implications in

the interpretation of spreading resistance measurements for profiling shallow

layers are presented. The limitations

of the multilayer Laplace equation analysis of spreading resistance in VLSI

profiling are also discussed.

[Contact: John Albers, (301) 975-2075]

Marchiando, J. F • , and Albers, J. , Effects of Ion-Implantation Damage on

Two-Dimensional Boron Diffusion in

Silicon, Journal of Applied Physics,

Vol. 61, No. 4 , pp. 1380-1391 (15

February 1987)

.

Well-defined control of boron implanted

in silicon during a high- temperature

short-time anneal is important in calculation of shallow p-n junction profiles

in metal o x i d e - s e m i c o n d u c t o

r

field-effect transistors (MOSFETs).

During an anneal, boron may exhibit

enhanced diffusion lasting about a second. Here, displacement damage is

removed largely by release and condensation of single vacancies, which enhance

the boron diffusion via the charged

vacancy mechanism. Model 2-D distributions of boron and displacement damage

implanted near a mask edge are used to

calculate the redistribution of boron

resulting from a seven-second anneal.

Boron redistributes further into the

bulk, while leaving the channel length

unaffected. The redistribution agrees

favorably with that reported in the

literature.

[Contact: Jay F. Marchiando, (301)

975-2088]

FAST SIGNAL ACQUISITION, PROCESSING,

AND TRANSMISSION

Waveform Metrology
Page 6 CEEE Technical Progress Bulletin - July 1987

Waveform Metrology (cont'd.

)

Released for Publication

Oldham, N.M., Parker, M.E., Young, A.,

and Smith, A.G. , A High Accuracy, 10

Hz — 1 MHz Automatic AC Voltage Calibration System, to be published in

the Proceedings of the IMTC/87 Conference Record (IEEE Instrumentation/Measurement Technology Conference),

Boston, Massachusetts, April 27-29,

1 987.

An automatic system for calibrating high

accuracy ac voltmeters and calibrators

is described. The system is based on

traditional coaxial thermal voltage

converters to provide measurement uncertainties of 5 to 20 ppm in the audio

frequency range and 5 to 150 ppm over

the full range from 1 0 Hz to 1 MHz.

Specialized hardware and measurement

techniques make it possible to achieve

these uncertainties in test periods of

approximately one minute. Random errors

introduced by the system are typically

less than 2 ppm (one standard deviation) . [Contact: N. Michael Oldham, (301)

975-2408]

Souders, T.M., Schoenwetter , H.K. , and

Hetrick, P.S., Characterization of a

Sampling Voltage Tracker for Measuring

Fast, Repetitive Signals, to be

published in the Proceedings of the

IMTC/87 Conference Record (IEEE

Instrumentation/Measurement Technology

Conference) , Boston, Massachusetts,

April 27-29, 1987.

An equivalent t ime - s amp 1 i ng and

digitizing system is described, together

with test methods for characterizing its

dynamic performance. Time-base errors,

linearity errors, step-response

parameters, and frequency response are

considered, and typical measurement

results are included. The system is

capable of state-of-the-art measurements

at rf frequencies.

[Contact: T. Michael Souders, (301)

975-2406]

Stenbakken, G.N., Laug, O.B., Perrey,

A.G., Bell, B.A., and Kibalo, T.H. , NBS Wideband Sampling Wattmeter, to

be published as NBS Technical Note

1 221 . The design and operation of a wideband

sampling wattmeter capable of measuring

distorted power signals with fundamental

frequencies from 1 Hz to 10 kHz and

harmonics up to 100 kHz are described.

The microprocessor-controlled wattmeter

uses asynchronous sampling of the voltage and current signals. The errors

associated with this type of operation

are described as are various methods of

correcting some of these errors. A

hardware multiplier-accumulator is used

to allow a large number of power samples

to be integrated for each measurement.

Sampling rates are variable up to a maximum of 300 kHz. A direct-memory-access unit is used to capture 4096

samples of both the voltage and current

signals. These data are used to calculate the average and rms of these signals. A special feature of the sampling

wattmeter is the use of programmable

time-delay circuits to compensate for

differential time delays between the two

input channels. Performance checks of

the wattmeter show that it has a measurement uncertainty of less than ±0.1

percent of full-scale range over the

indicated frequency range.

This technical note gives schematics of

the circuits and describes their operation. The software is described, and

flow charts and selected program listings are provided for the PASCAL programs. The results of calibration of

the instrument over the past year are also presented.

[Contact: Gerald N. Stenbakken, (301)

975-2440]

Recently Published

Adair, R.T. , Ehret, R.L., and Livingston, E.M., Measurement of RF Signal

Generator Phase Noise Using a OneGenerator Delay-Line Method, IEEE

Transactions on Instrumentation and
CEEE Technical Progress Bulletin - July 1987 Page 7

Waveform Metrology (cont'd.)

Measurement, Vol. IM-35, No. 4, pp.

496-502 (December . 1 986)

.

A technique is described which utilizes

a single generator and a delay line for

the measurement of frequency-domain

phase noise in synthesized signal

generators. Terms are defined and

equations developed for theory and

calculations of normalized phase-noise

sideband power in a 1 -Hz bandwidth

offset 20 kHz from signal frequencies of

interest. The system described covers

the range from 0.45 to 2000 MHz. The

function and contribution of each

component in the measurement system is

presented. Advantages of this method

are discussed and a brief error analysis

is given.

[Contact: Robert T. Adair, (303)

497-3461]

Kuffel, J. , Malewski, R.A., van

Heeswijk, R., and Lawton, R.A., Dynamic Performance of Digital Recorders

Used for Monitoring High-Voltage

Impulse Tests, IEEE Transactions on

Instrumentation and Measurement, Vol.

IM-35, No. 4, pp. 591-595 (December

1 986) . Frequency- and time-domain characteristics of digital transient recorders (in

short, digitizers) are discussed in

order to establish the requirements on

digitizers used for high-voltage testing. Results of an experimental study

performed on a 200-MHz 8-bit digitizer

are presented and related to the design

features of this instrument. The inherent design characteristics and their

influence on the digitizer dynamic performance are analyzed in view of simulation of the digitizer through a computer

model.

[Contact: Robert A. Lawton, (3 03)

497-3339]

Nahman, N.S., Status and Future Directions of Picosecond Domain Waveform

Measurements, Time-Domain Measurements in Electromagnetics, E.K. Miller,

ed. , Chapter 2 (Van Nostrand Re inhold

Co., New York, NY, 1986), pp. 45-71.

The main purpose of this chapter is to

(1 ) summarize the present-day capability

in time-domain measurements for pulses

or transient signals whose shape (evolution with time) occurs on a time scale

of the order of picoseconds, and (2)

offer some opinions as to the future

directions of electrical and optical

picosecond-domain pulse waveform measurements. Consequently, the techniques

and other data presented here are

limited to those suitable for such fast

signals. For example, all of the methods cited recognize that the signal-circuit interconnections or transmission

paths in devices and in instrumentation

are distributed or wave-guiding in

nature.

The review of the state of the art of

picosecond time-domain waveform measurements presented here includes measurements in both the electrical (dc through

mm waves, etc. ) the optical regions

(infrared through visible, etc. ) of the

electromagnetic spectrum. This review

is the latest edition of a series of

reviews on high-speed pulse measurements

compiled by the author commencing in

1967; specifically, this review updates

the 1983 review. The significance of

the Institute of Electrical and Electronic Engineers (IEEE) Pulse Standards

1 81 and 1 94 and of the identical International Electrotechnical Commission

(IEC) Standards 469-1 and 649-2 is discussed briefly. The classification of

time-domain measurements from the 1978

review is summarized and augmented with

basic instrumentation block diagrams.

The present-day capabilities are presented via temporal resolution state-ofthe-art charts using the 1978 format.

For the reader' s convenience, the 1 978

charts are reproduced here, along with

charts that show only those changes

that have occurred since 1978. The

references cited in all of the chart

entries are contained in the list of

references.

[Contact: Ramon C. Baird (303)

497-3301]
Page 8 CEEE Technical Progress Bulletin - July 1987

Waveform Metrology (cont'd.)

Oldham, N.M., Techniques and

Instruments for Automated Electrical

Measurements, MAPAN, Journal of

Metrology Society of India, Vol. 1, No.

1, pp. 25-27 (1986).

A summary of previous developments in

the field of automated electrical

measurements is presented.

[Contact: N. Michael Oldham, (301)

975-2408]

Sc hoenwe tter , H.K., Flach, D.R.,

Souders, T.M., and Bell, B.A., A

Precision Programmable Step Generator

for Use in Automated Test Systems,

NBS Technical Note 1230 (December

1 986)

.

A precision voltage step generator has

been designed for use in automated systems to test the dynamic response of

waveform recorders and other instruments. The programmable pulse parameters include transition polarity, pulse

length, and repetition rate. The

initial and final levels of voltage

steps are each programmable within the

range of ±1 V for a 50-ft termination and

within ±5 V for a high impedance load.

Voltage steps within these ranges settle

to within ±0.02% of full scale range in

less than 22 and 26 ns, respectively,

for small load capacitance. The corresponding transition durations are approximately 6 and 7 ns. [Contact: Howard K. Schoenwetter , (301)

975-2414]

Cryoelectronic Metrology

Released for Publication

Peterson, R.L., Sinusoidal Response of

dc SQUIDs for rf Power Measurements,

to be published in the NBS Journal of

Research.

Current, power, and attenuation

measurements with radiofrequency

Superconducting Quantum Interface

Devices (SQUIDs) are based on the fact

that the voltage from the microwave

readout circuit can be made nearly a sinusoidal function of the magnetic flux

threading the SQUID. We point out here

that an asymmetric dc SQUID with sufficiently low inductance can achieve a very sinusoidal output voltage with good

modulation depth. The spectral purity

of the sinusoid can be substantially

better than that obtained with rf SQUID

systems. The purity improves with increasing asymmetry of the junction

critical currents, and decreasing values

of the LIC product, where L is the

SQUID inductance and Ic is the smaller

of the critical currents. Results of

several calculations are presented.

Substantial improvement in SQUID methods

of rf current, power, or attenuation

measurement may thus be possible with

use of such dc SQUIDs.

[Contact: Robert L. Peterson, (303)

497-3750 or -3227]

Recently Published

McDonald, D.G. , High Accuracy in

Physics, Science, p. 829 (August 22,

1986)

.

Philip Abelson, in an editorial in

Science , reviews the National Research

Council report "Physics Through the

1990s" and writes "Of all the quantities

in physics, time is by far the most

accurately measured." I argue that the

Josephson effect has comparable

accuracy

.

[Contact: Donald G. McDonald, (303)

497-51 1 3]

Muhlfelder, B., Beall, J. A., Cromar,

M.W., and Ono, R.H., Very Low Noise,

Tightly Coupled, dc SQUID Amplifiers,

Applied Physics Letters, Vol. 49, No.

17, October 27, 1 986, pp. 1118-1120.

We have fabricated and tested thin-film,

niobium edge junction, double transformer, dc superconducting quantum interference devices (SQUIDs) that were stable

under room- temperature storage and thermal cycling and that had very good noise

performance. The input inductance,
CEEE Technical Progress Bulletin - July 1987 Page 9

Cryoelectronic Metrology (cont'd.

)

approximately 1.7 yH, was large enough

to facilitate good matching to many

experiments. When the SQUID was

operated as a small-signal amplifier,

the minimum detectable energy per unit

bandwidth (Se ) was 5

x 10" 33 J/Hz at

100 kHz, referred to the SQUID loop

(uncoupled) • The minimum detectable

energy per unit bandwidth was 1.8 x

1 0- 3

1

J/Hz at 100 kHz, referred to the

input coil. The SQUIDs had good characteristics for flux-locked operation

since the small signal Se was low over

a substantial range of bias current and

magnetic flux. For operations in a flux-locked feedback circuit, Se was 6

x 10~ 32 J/Hz at 1 kHz.

[Contact: James T. Beall, (303)

497-5989]

Antenna Metrology

Recently Published

Baird, R.C., Daywitt, W.C., Newell,

A.C., Perera, S., Repjar, A.G., Wait,

D.F., and Estin, A.J. , Calibration

Requirements for EHF Satellite Conununication Systems, NBSIR 86-3058

(October 1986).

The calibration and measurement support

requirements of millimeter-wave satellite systems such as MILSTAR have been

investigated. Needs for measurements on

satellite systems are reviewed. An

overview of the various means available

for calibrating antenna gain, one of the

key measurements that needs to be

accurately accomplished, is presented.

Essentially three new measurement

problems arise because of operating in

the upper SHF and EHF frequency ranges.

First, without adequate methods to

measure the atmospheric loss, the

accuracy of effective isotropic radiated

power (EIRP) measurements in the 20 to

45 GHz range can be no better than 0.5

dB to 3 dB (depending on frequency and

antenna elevation angle) , which is

inadequate for MILSTAR requirements.

Second, standards and measurement

support services are not presently

available from the National Bureau of

Standards and are needed to support

mil lime ter-wave antenna gain and thermal

noise measurements. Third, if the sun and/or moon are to be used for measuring

the earth terminal G/T, earth terminal

antenna gain, or satellite EIRP in the

millimeter region, they need to be

appropriately characterized at those

frequencies

.

[Contact: Ramon C. Baird, (303)

497-3301]

Hill, D.A., Far-Field Transient

Response of an Antenna fron Near-Field

Data, NBSIR 86-3063 (December 1986).

A theoretical basis for calculating the

transient far-field response of an an- tenna from planar near-field data in

either the time domain or the frequency

domain has been developed. A double

integral must be evaluated if we begin

with time-domain data, but a triple

integral must be evaluated if we begin

with frequency-domain data. However,

the frequency-domain integrals are in a form that is suitable for three-dimensional fast Fourier transform. Two

idealized examples are studied, and

identical results are obtained starting

with frequency-domain or time-domain

data. The main practical difficulty in

determining the transient response is

the large number of near-field samples

that are required. If data are taken at

only a few near-field points, then the

singularity expansion method presents a possible method of determining the com- plex resonances of the antenna under

test.

[Contact: David A. Hill, (303)

497-3472]

Hill, D.A., Out-of-Band Response of

Reflector Antennas, IEEE Transactions

on Electromagnetic Compatibility, Vol.

EMC- 28, No. 2, pp. 80-89 (May 1986).

[This paper includes Sections 1 through

3 and Appendix A of NBSIR 85-3021,

April 1 985. ] The response of reflector antennas to
Page 1

Q

CEEE Technical Progress Bulletin - July 1987

Antenna Metrology (cont'd.)

out-of-band frequencies has been

analyzed using physical optics. A

simple approximate expression has been

obtained for the effective aperture, and

this expression yields both the receiving pattern and the frequency dependence

of the on-axis gain. The theory has

been compared with published out-of-band

measurements, and the pattern agreement

is good, but the measured gain falls

below the theory. This discrepancy is

caused by mismatch loss in the coax-towaveguide adapter.

[Contact: David A. Hill, (303)

497-3472]

Muth, L.A., Displacement Errors in

Antenna Near-Field Measurements and

Their Effect on the Far Field, NBS

Technical Note 1 306 (October 1 986).

The effects of probe displacement errors

in the near-field measurement procedure

on the far-field spectrum are studied.

Expressions are derived for the displacement error functions that maximize

the fractional error in the spectrum

both for the on-axis and off-axis directions. Planar x-y and z-displacement

errors are studied first, and the

results generalized to position errors

in cylindrical and spherical scanning.

Near-field models are used to obtain

order-of-magnitude estimates for the

fractional error as a function of

relevant scale lengths of the near

field, defined as the lengths over which

significant variations occur.

[Contact: Lorant A. Muth, (303)

497-3603]

Noise Metrology

Recently Published

Baird, R.C., Daywitt, W.C., Newell,

A.C., Perera, S., Repjar, A.G. , Wait,

D.F., and Estin, A.J. , Calibration

Requirements for EHF Satellite Communication Systems, NBSIR 86-3058 (October 1 986)

.

The calibration and measurement support

requirements of mil lime ter-wave satellite systems such as MILSTAR have been

investigated. Needs for measurements on

satellite systems are reviewed. An

overview of the various means available

for calibrating antenna gain, one of the

key measurements that needs to be

accurately accomplished, is presented.

Essentially three new measurement

problems arise because of operating in

the upper SHF and EHF frequency ranges.

First, without adequate methods to

measure the atmospheric loss, the

accuracy of effective isotropic radiated

power (EIRP) measurements in. the 20 to

45 GHz range can be no better than 0.5

dB to 3 dB (depending on frequency and

antenna elevation angle) , which is

inadequate for MILSTAR requirements.

Second, standards and measurement

support services are not presently

available from the National Bureau of

Standards and are needed to support

mil lime ter-wave antenna gain and thermal

noise measurements. Third, if the sun

and/or moon are to be used for measuring

the earth terminal G/T, earth terminal

antenna gain, or satellite EIRP in the

millimeter region, they need to be

appropriately characterized at those

frequencies.

[Contact: Ramon C. Baird, (303)

497-3301 ] Microwave and Millimeter-Wave Metrology

Recently Published

Adair, R.T., Reeve, G.R., and Gatterer,

L.E., Millimeter-Wave Standards: An

Emerging Need, IEEE Transactions on

Instrumentation and Measurement, Vol.

IM-35, No. 4, pp. 376-382 (December

1986) . Several technology surveys concerning

millimeter-wave (MMW) measurement needs

and capabilities have been conducted by

the National Bureau of Standards (NBS),

Boulder Laboratories, and others. The

results of some of these studies are

summarized. Current MMW standards and

calibration capabilities at NBS are

reviewed. The lack of national stan—
Page 1

1

CEEE Technical Progress Bulletin - July 1987

Microwave & Millimeter-Wave (cont'd.)

dards in certain frequency bands may

lead to problems with specification,

acceptance testing, and calibration of

some components and systems.

[Contact: Robert T. Adair, (303)

497-3461]

Ginley, R.A., and Allred, C.M., 1,25

MHz Attenuation Measurement System.

IEEE Transactions on Instrumentation

and Measurement, Vol. IM-35, No. 4, pp.

463-466 (December 1986).

A system has been developed to make

highly accurate measurements of nominally 6-dB increments of attenuation at

1.25 MHz. Initial experiments indicate

a typical systematic error of 5 yB (1 yB

= 0.00001 dB) with a resolution of 1 yB.

A special linearity measurement system

( LMS ) using NBS-cons true ted, linear

tuned hybrids and power detectors has

been used to determine the nonlinearity

of a tuned 1.25-MHz power detector. This

detector utilizes a single thermistor

bead design with thermal isolation to

obtain nearly linear tracking of a 4:1

change in input power. The nonlinear

correction for this change, determined

by the LMS, is on the order of 1 3 yB for

the detector presently in use. This

calibrated detector and another of similar design are used in the attenuation

measurement system to make power ratio

measurements to determine the change in

attenuation of the device under test. It

is anticipated that changes of approximately 6 dB can be measured with initial

insertion loss of up to 100 dB with an

accuracy of 0.001 dB. A special design

consideration will be required for units

used for calibration in order to keep

mismatch errors from significantly

degrading the accuracies estimated

above.

[Contact: Ronald A. Ginley, (303)

497-3634]

Sequeira, H.B., and Yates, B.C., Approach for Evaluating Effects of Wall

Losses on Quarter-Wave Short-Circuit

Impedance Standards, IEEE Transactions on Microwave Theory and Techniques, Vol. MTT-33, No. 11, pp. 1106-

1109 (November 1985)

The conservation of energy principle and

first-order perturbation theory have

been applied to obtain formulas for the

physical lengths and reflection coefficient magnitudes of quarter-wave coax- ial and rectangular waveguide shortcircuit impedance standards. The

expressions for the physical lengths

ensure zero phase angle at the mating

interface when wall losses are present.

The method can be extended to include

small dielectric and magnetic losses,

and requires only knowledge of the lossfree solutions. It can also be applied

to other waveguiding structures which

support uncoupled modes.

[Contact: Billie C. Yates, (303)

497-3568]

Optical Fiber Metrology

Released for Publication

Day, G.W., and Franzen, D.L., Conference Report: Symposium on Optical Fiber

Measurements, to be published in the

NBS Journal of Research.

This report is a brief summary of the

4th Symposium on Optical Fiber Measurements, held September 9-10, 1986 at the

NBS Boulder Laboratories.

[Contact: Gordon W. Day, (303)

497-5204]

Electro-Optic Metrology

Released for Publication

Franzen, D.L. , Yamabayashi, Y. , and

Kanada, T. , Optical Sampling with

Gain-Switched Pulse Compressed Distributed-Feedback Laser Diodes.

Chirped pulses from gain- switched, distributed-feedback laser diodes at a wavelength of 1.3 ym are compressed to

8.7 ps full width at half maximum by the
Page 1

CEEE Technical Progress Bulletin - July 1987

Electro-Optic Metrology (cont'd.

)

Released for Publication

linear dispersion properties of single

mode fiber. These pulses are used to

optically sample waveforms from other

laser diodes. The all-fiber sampling

system uses a coupler to combine beams,

thus eliminating critical alignment.

[Contact: Douglas L. Franzen, (3 03)

497-3346 or -5342]

Recently Published

Day, G.W., Hale, P.D. , Deeter, M.,

Milner, T.E., Conrad, D. , and Etzel,

S.M., High Precision Electro-Optic

and Magneto-Optic Sensors for Power

System Applications: Technical

Feasibility, NBS Technical Note

1 307 (March 1 987)

.

The principles of electro-optic and

magneto-optic sensors suitable for use

in power system applications are re- viewed with particular attention to the

properties of materials and components

that limit the precision of such sensors. Section topics include precision

and accuracy in electro-optic and magneto-optic sensors; electro-optic and

magneto-optic sensor configurations

suitable for current and voltage measurements; critical evaluation of electro-optic sensor technology; critical

evaluation of magneto-optic sensor technology; and suggested approaches to the

development of high-precision optical

current and voltage sensors. Data on a number of materials are collected and

presented. For high-precision electrooptic sensors, it is recommended that

crystals of the polar class having point

symmetry 43 m be used. For highprecision magneto-optic sensors, a lead

glass with a low stress-optic coefficient is recommended. Choices for

other components are also suggested.

For both types of sensors, a precision

of roughly ±1% over a 100°C temperature

range should be attainable. To achieve

a precision better than that, it will be

necessary to use temperature compensation techniques, several of which are

proposed and discussed.

[Contact: Gordon W. Day, (303)

497-5204]

Other Fast Signal Topics

Recently Published

Hill, D.A., Electromagnetic Wave

Propagation in an Asymmetrical Coal

Seam, IEEE Transactions on Antennas

and Propagation, Vol. AP-34, No. 2, pp.

244-247 (February 1986).

Electromagnetic wave propagation in a coal seam is analyzed for the case where

the surrounding floor and roof rocks

have differing electrical properties.

Numerical results are presented for the

attenuation rate and field distribution

of the dominant mode. Even when the

roof and floor conductivities are

different, the vertical electric field

and the horizontal magnetic field are

the dominant components, and they are nearly constant within the coal seam. The results have application to mine

communication and remote sensing of coal

seams

.

[Contact: David A. Hill, (303)

497-3472]

Hill, D.A., and Wait, J.R., Anomalous

Vertical Magnetic Field for Electromagnetic Induction in a Laterally Varying

Thin Conductive Sheet, Radio Science,

Vol. 21, No. 4, pp. 617-621 (JulyAugust 1 986)

.

We employ a simple model to show how the

natural electromagnetic field on the

surface of the earth, which has a strong

horizontal magnetic field component, can

be converted to a significant vertical

magnetic field at the surface. Such a conversion mechanism will be caused by

lateral variations of the subsurface

conductivity structure. Our idealized

model is a thin conducting sheet with a periodic variation of the conductivitythickness product in one horizontal

direction only.

[Contact: David A. Hill, (303)

497-3472]
CEEE Technical Progress Bulletin - July 1987 Page 1

3

Other Fast Signal Topics (cont'd.)

Perrey, A.G. , Bell, B.A., and Treado,

M.J., Evaluation of Electronic Monitoring Devices, NBSIR 86-3501

(December 1986).

Electronic Monitoring Devices (EMDs) are used to monitor the presence of individuals within a given area who are responsible to the criminal justice system but

not confined to institutions. Several

EMDs were tested to measure operational

characteristics such as operating frequency, approximate range of operation,

component capability, and tamper resistance. Tests were conducted in an open

field, wooden residence, high rise metalbuilding, and in a laboratory environment.

[Contact: Arnold G. Perrey, (301)

975-2782]

ELECTRICAL SYSTEMS

Power Systems Metrology

Released for Publication

Laug, O.B., A Precision Power Amplifier for Power/Energy Calibration Applications, to be published in the

Proceedings of the IMTC/87 Conference

Record (IEEE Instrumentation/Measurement Technology, Conference), Boston,

Massachusetts, April 27-29, 1987.

A precision power amplifier for use in

power/energy calibration applications is

described. The amplifier was primarily

designed to boost the output amplitude

of a dual-channel digital generator to

provide the nominal 120 or 240 rms voltage component of a "phantom" calibration

power source. The amplifier has a fixed

gain of 40 and can provide a maximum

output voltage swing of 970 V peak-topeak or 340 V rms at 100 mA rms. The

bandwidth is from dc to 150 kHz, and at

60 Hz the observed no-load, short-term

amplitude and phase instabilities are ±5

ppm and ±5 microradians, respectively.

The amplifier design uses high-voltage

N-channel MOSFETs in the output driver

stage, together with a unique circuit

topology of opto-isolators between the

low-level input stage and the high-level

output stage.

[Contact: Owen B. Laug, (301)

975-241 2]

Superconduc tors

Released for Publication

Fickett, F.R., and Capobianco, T.E.,

Conductors for Advanced Energy Systems.

In this report we present the results of

extensive mechanical-properties tests on

a large number of oxygen-free copper

samples representing a range of producers and wire tempers. Tests at both

room temperature and liquid-helium temperature (4 K) are reported. A

specialized apparatus developed for the

low-temperature tests is described.

Results of the many tests are presented

in graphical and tabular form. The most

interesting of the results is that it

appears possible to predict the strength

of oxygen-free copper wires at low temperatures by the measurement of the

residual resistance ratio (RRR) , the

ratio of the room temperature resistance

to that measured at 4 K. This result is

of great importance in applications,

since many laboratories are able to

measure RRR, but few can do low- temperature mechanical properties tests.

[Contact: Frederick R. Fickett, (303)

497-3785]

Goodrich, L.F., Bray, S.L., Dube, W.P.,

Pittman, E.S., and Clark, A.F.,

Development of Standards for Superconductors, Interim Report, January - December 1985, to be published as NBSIR 87-3066.

A cooperative program with the Department of Energy, the National Bureau of

Standards, and private industry is in

progress to develop standard measurement

practices for use in large-scale applications of superconductivity. The goal

is the adoption of voluntary standards
Page 1

CEEE Technical Progress Bulletin - July 1987

Superconduc tors (cont'd.)

for the critical parameters and other

characterizations of practical superconductors, Progress for the period January through December 1985 is reported.

The major effort was the measurement of

large-conductor critical currents.

Other work reported here includes stability and a discussion of possible

future Standard Reference Materials.

[Contact: Loren F. Goodrich, (303)

497-3143]

Moreland, J. , Ekin, J.W., Goodrich,

L.F., Capobianco, T.E., Clark, A.F.,

Kwo, J. , and Hong, M., Break-Junction

Tunneling Measurements of the High-Tc

Superconductor Y 1 Ba2Cu 3 0g-g

,

Current-voltage tunneling characteristics in a high-critical- temperature

superconducting material containing

predominately Y 1 Ba 2 Cu 30 g -

(5 have been

measured using the break-junction technique. Sharp gap structure was observed, with the largest superconductive

energy gap measured to be A = 19.5 meV ±

1 meV, assuming a superconductor-insulator-superconductor junction. Using the

observed critical temperature of 93 K

(mid-point of the resistive transition),

this energy gap corresponds to

2A/k BTc = 4.8 at T = 4 K.

[Contact: John Moreland, (3 03)

497-3641]

Moreland, J. , Clark, A.F., Goodrich,

L.F., Ku, H.C., and Shelton, R.N.,

Tunneling Spectroscopy of a La-Sr-Cu-O

Break Junction: Evidence for StrongCoupling Superconductivity.

Detailed structure in the quasiparticle

tunneling has been observed in lanthanum-s trontiun-copper-oxide superconductive tunneling junctions using the

break-j unction technique. Variability

in the energy gap and associated structure in the current-voltage curves is

observed indicating significant inhomogeneity in the superconducting properties. Large energy gaps (7.0 to 9.0

meV) and deep structure in the conductance derivatives are evidence for a strong coupling mechanism.

[Contact: John Moreland, (303)

497-3641]

Moreland, J., Clark, A.F., Ku, H.C., and

Shelton, R.N., Electron Tunneling

Measurement of the Energy Gap in a La-Sr-Cu-0 Superconductor.

The break-junction technique has been

used to determine the energy gap of

lanthanum-strontium-copper-oxide, one of

the new high-critical- temperature superconductors. In this technique, a small

piece of bulk material is electromechanically fractured under liquid helium and

the freshly fractured surfaces adjusted

to form a tunneling barrier with the

helium as the insulator. Extraordinarily precise mechanical adjustment permits the study of electron tunneling

phenomena between pieces of a bulk

s upe rc onduc tor

.

[Contact: John Moreland, (303)

497-3641

]

Recently Published

Benson, R.G., Goldfarb, R.B., and

Pittmann, E.S., Quench Circuit for

Electronic Instruments Used with

Superconducting Magnets, Cryogenics,

Vol. 26 (Butterworth & Co. Ltd.,

August/ September 1986), pp. 482-483.

A multifunction circuit is described

that protects instruments connected or coupled to a superconducting magnet in

the event of a quench.

[Contact: Ronald B. Goldfarb, (303)

497-3650]

Goldfarb, R.B, and Ekin, J.W., Hysteresis Losses in Fine-Filament InternalTin Superconductors, Cryogenics, Vol.

26 (Butterworth & Co. Ltd. , August/September 1986), pp. 478-481.

Hysteresis losses were measured on a series of fine-filament Nb^Sn superconductors made by the internal- tin process. Hysteresis was measured as a function of filament diameter and inter-
CEEE Technical Progress Bulletin - July 1987 Page 1

5

Superconduc tors (cont'd.)

filament separation using a vibratingsample magnetometer in transverse

magnetic field. Losses were greater

than expected compared to predictions of

the critical-state model that expresses

loss as a function of filament diameter.

Micrographs of the reacted wire cross

sections show some in te r f i lame n

t

bridging for all wires. This bridging

gives rise to effective filament

diameters that are greater than actual

diameters. The critical interfilament

separation, above which the losses would

be expected to follow the critical-state

model, was determined.

[Contact: Ronald B. Goldfarb, (303)

497-3650]

Goldfarb, R.B., Internal Fields in

Magnetic Materials and Superconductors, Cryogenics, Vol. 26 (Butterworth & Co. Ltd. , August/ September

1986), pp. 621-622.

This paper reviews some of the concepts

needed for the correct analysis of magnetization data, both for magnetic materials and superconductors. Demagnetization factors, initial suceptibilities

,

and hysteresis losses are discussed.

[Contact: Ronald B. Goldfarb, (3 03)

497-3650]

Magnetic Materials and Measurements

Recently Published

Capobianco, T.E., Moulder, J. C., and

Fickett, F.R., Flaw Detection with a

Magnetic Field Gradioneter, Proceedings of the Fifteenth Symposium on

Nondestructive Evaluation, San Antonio,

Texas, April 23-25, 1985, pp. 15-20.

When eddy currents are induced in a conductor, flaws deflect the eddy cur- rents and perturb the associated electric and magnetic fields. In conventional eddy current testing, the perturbed fields associated with a flaw are

detected as a change in the impedance of

the test coil used to induce the eddy

currents. More direct methods for

detecting and characterizing flaw-perturbed fields, both electric and magnetic, have also been developed. We

describe a method for determining the

normal component of the magnetic field

gradient caused by a flaw. A novel

feature of the measurement system is the

use of a Superconducting Quantum Interface Device (SQUID). The SQUID provides

more sensitivity than conventional

detection methods, and the possibility

of calibration based on a fundamental

physical quantity: the flux quantum. We

report the results of a series of measurements on a fatigue crack and several

manufactured defects in aluminum alloy

specimens using this system. The effect:

of edge proximity compared to flaw signal and a figure of merit are also discussed.

[Contact: Thomas E. Capobianco, (303)

497-3141]

Goldfarb, R.B., Internal Fields in

Magnetic Materials and Superconductors, Cryogenics, Vol. 26 (Butterworth & Co. Ltd. , August/September

1986), pp. 621-622.

This paper reviews some of the concepts

needed for the correct analysis of magnetization data, both for magnetic materials and superconductors. Demagnetization factors, initial suceptibilities,

and hysteresis losses are discussed.

[Contact: Ronald B. Goldfarb, (303)

497-3650]

ELECTROMAGNETIC INTERFERENCE

Radiated Electromagnetic Interference

Released for Publication

Ma, M.T., and Bensema, W.D., Automated

TEM Cell for Measuring Unintentional EM

Emissions

.

This paper summarizes the basic electrical properties of a transverse electromagnetic (TEM) cell, and the underlining

theoretical background, based on which a TEM cell is used to measure accurately
Page 1

6

CEEE Technical Progress Bulletin - July 1987

Radiated EMI (cont'd.)

the emission of an unknown, unintentional leakage source. The theory and measurements have been verified by the

results of a simulated example and two

experiments using a spherical dipole

radiator and a small loop antenna.

Recent development of an automated measurement system is also included.

[Contact: Mark T. Ma, (303) 497-3800]

Recently Published

Adams, J.W., and Vanzura, E., Shielding Effectiveness Measurements of Plastics, EMC Technology, pp. 39-42

(September-October 1 986)

.

Measurement of shielding effectiveness

of plastic materials presents problems

because of the insulating nature of many

plastics. A method of making the measurements using a flanged coaxial holder

overcomes these limitations.

[Contact: John W. Adams, (303)

497-3328]

Bensema, W.D., Koepke, G.H., and Medley,

H.W., Handbook for NBS Multisensor

Automated EM Field Measurement System,

NBSIR 86-3056 (October 1986).

A system is described that monitors and

collects electromagnetic (EM) field

strength information at five (optionally

10) locations simultaneously. The system has two modes of operation: (1 ) for

sampling EM fields that are stationary

for times of the order of 200 ms, and

(2) for sampling changing EM fields with

a system resolution of 10 jjs. Sensing

elements for Mode 1 consist of three

electrically short orthogonal dipoles

mounted together, single dipole elements, or small loop antennas. Each

element feeds a separate data input

channel for a total of 1 5 (optionally

30) channels. Radiofrequency energy is

converted to dc by a diode detector at

each dipole. Mode 2 sensors are diode

detectors driven by broadband antennas.

Real-time system data processing includes calculation of field strength

based on probe calibrations and processing of resultant data to satisfy measurement goals.

[Contact: William D. Bensema, (303)

497-3465]

Cruz, J.E., and Larsen, E.B., Assessment: of Errors for Some Typical MILSTD-461/462 Types of Measurements

,

NBS Technical Note 1300 (October

1 986)

.

This report deals with the instrumentation and equations for several systems

used by the U.S. Army for electromagnetic compatibility (EMC) testing and

calibrations. Most testing for MIL-STD461/462 is performed in a shielded

enclosure (screenroom) rather than an

open field site, which leads to uncertainty in the measurement of emissions

from electronic equipnent, or the susceptiblity of equipnent to radiation.

Assessment of error bounds by the

National Bureau of Standards is covered

in this report, and suggestions are

given for improving the measurements.

Four areas of concern were studied as follows: (a) EM fields generated in a parallel-plate transmission line (stripline), (b) EM fields beneath a singlewire transmission line in a screenroom

(longwire line), (c) determination of

antenna factors for EMI antennas located

in a screenroom, and (d) calibration of

EMI receivers to measure broadband

impulsive signals. Most EMC antennas at

NBS are calibrated at an open field site

or in an anechoic chamber. This report

presents antenna factors determined in a typical screenroom using the two-antenna

method, and comparison with those determined at an open field site. The video

pulse technique prescribed in MIL-STD462 for calibrating EMI receivers was

also evaluated. Four different methods

were tested for comparison with the

MIL-STD approach. They are defined and

discussed in this report.

[Contact: Jose E. Cruz, (303)

497-3763]

Jesch, R.L. , A Survey of Triaxial and
CEEE Technical Progress Bulletin - July 1987 Page 1

7

Radiated EMI (cont'd.)

Mode-Stirred Techniques for Measuring

the Shielding Effectiveness of Connectors and Cables, NBSIR 86-3060

(October 1986).

This report is the result of an extensive literature search conducted in the

field of connectors and cables, with

reference to radio-frequency leakage

characteristics and capabilities for

measuring shielding effectiveness of

connectors and cables. The report

reviews two measurement techniques for

determining shielding effectiveness:

the triaxial test technique that has

been used for over 20 years and the

mode-stirred test technique that recently has started to gain in popularity.

From this survey, certain inferences are

drawn about these techniques in terms of

device configuration, frequency range,

and ease of measurement and are presented in chart form for comparative

purposes.

[Contact: Ramon L. Jesch, (303)

497-3496]

Kanda, M. , Time-Domain Sensors and

Radiators, Time-Domain Measurements

in Electromagnetics, E.K. Miller, ed. , Chapter 5 (Van Nostrand Re inhold Co. , New York, NY, 19-86), pp. 1 22-174.

The purpose of this chapter is to discuss various sensors and radiators com- monly used for time-domain antenna measurements. The sensors and radiators

discussed here are passive analog

devices that convert the electromagnetic

quantity of interest to a voltage or current at their terminal ports. Moreover, they are primary standards in the

sense that their transfer functions can

be calculated from their geometries and

are flat (frequency-independent) across

a wide frequency range. One of the

major requirements of these sensors and

radiators is that the electromagnetic

far field, for transmission or reception, be a replica or high-fidelity

derivative of the original pulse.

Because of their usefulness in electricfield strength measurements, linear

antennas nonuniformly and continuously

loaded with resistance, or both resistance and capacitance, are discussed.

Also, a conical antenna and an asymptotic conical antenna are examined from

the standpoint of improved antenna characteristics. Various types of transverse electromagnetic (TEM) horns are considered for improved directivity,

e.g. , a conducting TEM horn and a resistively loaded TEM horn. For magneticfield strength measurements, a loop

antenna with uniform resistive loading

is discussed.

Section 5.1 discusses one of the important properties governing the transmitting and receiving transfer functions of

an antenna. The frequency-domain and

time-domain characteristics of the various electric- and magnetic-field sensors

mentioned above are then covered in

Secs. 5.2 and 5.3, respectively.

[Contact: Motohisa Kanda, (303)

497-5320]

Kanda, M., and Wyss, J.C., Evaluation

of Off Axis Measurements Performed in

an Anechoic Chamber, NBS Technical

Note 1 305 (October 1986).

The performance of a rectangular radiofrequency anechoic chamber is measured

when the device under test is not on the

center line of the launch antenna. An

electrically small field probe is

repeatedly scanned longitudinally away

from the launch antenna and into the

chamber. With each scan, various parameters are changed, including: 1) horizontal and vertical position of the

probe with respect to the center line of

the launch antenna; 2) frequency; and 3)

type of launch antenna. With the probe

located 1 m off the center line and

scanning between 2 to 6 meters from the

launch horn, the uncertainty due to

being off the center line ranges from ±1

dB at 250 MHz to ±5.0 dB at 800 MHz and

above. If the probe is within ±50 cm of

center line, the uncertainty is no more

than ±1.5 dB at 800 MHz; and for ±25 cm of center line, the uncertainty is fur-
Page 18 CEEE Technical Progress Bulletin - July 1987

Radiated EMI (cont'd.

)

ther reduced to ±0.5 dB at 800 MHz.

[Contact: Motohisa Kanda, (303)

497-5320]

Ma, M.T. , and Kanda, M., Electromagnetic Compatibility and Interference

Metrology, NBS Technical Note 1099

(July 1986).

The material included in this report is

intended for a short course on electromagnetic comp a tibili ty/in ter fere nee

(EMC/EMI) metrology to be offered jointly by the staff of the Fields Characterization Group and the Interference Characterization Group of the Electromagnetic Fields Division. The purpose of

this short course is to present a review

of some of the radiated EMC/EMI measurement methods, to which the National

Bureau of Standards (NBS) at Boulder,

Colorado, has made significant contributions during the past two decades. The

technical foundation for these methods,

and interpretations of the measured

results are emphasized, as well as strengths and limitations. The entire

course is presented in nine chapters

with the introductory part given as Chapter 1 . The particular measurement

topics to be covered are: i) open sites

(Chapters 2 and 6) , ii) transverse electromagnetic cells (Chapter 3) , iii)

techniques for measuring the electromagnetic shielding of materials (Chapter

4), iv) anechoic chambers (Chapter 5),

and v) reverberating chambers (Chapter

8). In addition, since a small probe

antenna plays an important role in some

of the EMC/EMI measurements covered

herein, a separate chapter on various

probe systems developed at NBS is given

in Chapter 7. Selected contemporary EMI

topics such as the characterization and

measurement of a complex EM environment,

interferences in the form of out-of-band

receptions to an antenna, and some

conducted EMI problems are also briefly

discussed (Chapter 9)

.

[Contact: Mark T. Ma, (303) 497-3800]

Randa, J. , and Kanda, M., A Lattice

Approach to Volumes Irradiated by Onknown Sources, NBS Technical Note

1303 (October 1986).

We suggest an approach to the characterization of electromagnetic environments

irradiated by unknown sources. The

approach is based on the numerical solution of Maxwell's equations subject to

the constraints imposed by the measured

values of the field at a small number of

measurement points and by boundary con- ditions. A thorough examination is

presented of two methods for the numerical solution. The examples attempted

demonstrate the approach, but reveal

that neither technique is fully successful. Possible future directions are

suggested.

[A paper based on the contents of this

Technical Note is scheduled for presentation at the Seventh Symposium and

Technical Exhibition on EMC (Zurich,

Switzerland, March 1987) under the title

"A Lattice Approach to Environments

Irradiated by Unknown Sources" and will

appear in the proceedings of that Symposium. A second paper based on this

material has been submitted to the IEEE

Transactions on Electromagnetic Compatibility with the title "A New Approach to

Volumes Irradiated by Unknown Sources.]

[Contact: James P. Randa, (303)

497-31 50]

Wilson, P.F., and Ma, M.T. , Electromagnetic Shielding Effectiveness:

Measurement Techniques and Interpretations, 1986 IEEE Regional Conference

& Exhibition on Electromagnetic Compatibility, Anaheim, California, February

6, 1986, pp. 1-14.

A material's shielding capability is

generally measured in terms of insertion

loss: the field reduction between a transmitter and a receiver achieved by

introducing the shield material. Ambiguities often arise when one attempts to

interpret specific measurement results.

Insertion loss data depend not only on the shield material tested, but also on
CEEE Technical Progress Bulletin - July 1987 Page 1

9

Radiated EMI (cont'd.)

the measurement procedure and other

parameters such as the antenna types

(both transmitting and receiving) used

and their positioning, the incident

waveform and its wave impedance,

transient effects, and the contact

resistance between the test material and

its mount, if any.

[Contact: Perry F. Wilson, (303)

497-3842]

Wilson, P.F., and Ma, M.T., Methods

for Measuring the Near-Field and FarField Shielding Effectiveness of Materials, Proceedings of the EMC Expo

'86 Conference, Washington, D.C., June

1 6-19, 1986, pp. T281-T286.

Techniques for measuring the shielding

effectiveness of materials are investigated. Specific approaches considered

are coaxial transmission line holders

and the use of a time-domain signal for

simulating plane wave shielding performance, and the dual transverse

electromagnetic (TEM) cell and an

apertured TEM cell in a reverberation

chamber for the simulation of near-field

shielding capability. The advantages

and limitations of each technique are

summarized.

[Contact: Perry F. Wilson, (303)

497-3842]

ADDITIONAL INFORMATION

Lists of Publications

Gibson, K. A., Page, J.M., and Miller,

C .K . S . , A Bibliography of the NBS

Electromagnetic Fields Division Publications, NBS IR 85-3040 (February

1 986)

.

This bibliography lists publications of

the National Bureau of Standards' Electromagnetic Fields Division for the

period from January 1984 through September 1985, with selected earlier publications from the Division's predecessor

organizations.

[Contact: Kathryn A. Gibson, (303)

497-31 32]

Kline, K. E., and DeWeese, M.E., Metrology for Electromagnetic Technology:

A Bibliography of NBS Publications

,

NBSIR 86-3048 (June 1986).

This bibliography lists the publications

of the personnel of the Electromagnetic

Technology Division of NBS in the period

from January 1970 through December 1985.

A few earlier references that are directly related to the present work of

the Division are included.

[Contact: Kathryn E. Kline, (303)

497-3678]

Palla, J.C., and Meiselman, B., Electrical and Electronic Metrology: A

Bibliography of NBS Electrosystems

Division Publications, NBS List of

Publications 94 (January 1987).

This bibliography covers publications of

the Electrosystems Division, Center for

Electronics and Electrical Engineering,

NBS, and of its predecessor sections for

the period January 1963 to January 1987.

A brief description of the Division'

s

technical program is given in the introduction.

[Contact: Jenny C. Palla, (301

)

975-2220]

Walters, E.J. , Semiconductor Measurement Technology: A Bibliography of NBS

Publications for the Years 1962—1986,

NBSIR 87-3522 (February 1987).

This bibliography contains reports of

work performed at the National Bureau of

Standards in the field of Semiconductor

Measurement Technology in the period

from 1962 through December 1986. An

index by topic area and a list of

authors are provided.

[Contact: E. Jane Walters, (301)

975-2050]

1987 CEEE CALENDAR

July 28-30 (Vail, CO)

Short Course on Optical Fiber Measurements. This course is sponsored by

the National Bureau of Standards and the
Page 20 CEEE Technical Progress Bulletin - July 1987

1 987 CEEE Calendar (cont'd.

)

University of Colorado with the cooperation of members of industry who serve as faculty together with staff from the

Electromagnetic Technology and Electromagnetic fields Divisions. The course

is intended for scientists and engineers

involved in optical fiber characterization and emphasizes concepts, techniques, and apparatus used in measuring

engineering parameters of telecommunications-grade fibers.

The following major topic areas are addressed: optics for communications, em- phasizing geometric optics concepts;

fiber properties and parameters; indexprofile measurements; fiber bandwidth

measurements in the frequency and time

domains; fiber attenuation measurements;

connector and splice losses; optical

time-domain ref lectometry concepts and

applications; single-mode fibers; statistics and error analyses, measurement

uncertainties; and fibers for sensors.

[Contact: Office of Conference

Services, University of Colorado (303)

492-8630; Robert L. Gallawa (303)

497-3761; or Matt Young (303) 497-3223]

September 14-16 (Research Triangle Park,

NC)

VLSI and GaAs Packaging Workshop.

This Workshop is co-sponsored by the

Components, Hybrids, and Manufacturing

Technology Society of IEEE and NBS;

attendees are expected to be knowledgeable in the field and to participate in

discussions. Topic areas include: VLSI

and wafer scale package design (characterization and implementation, cost and

performance driven solutions) ; package

thermal design (characteristics, re- sults, and issues); package interconnection options (wire bonding, TAB, flip

nection options (wire bonding, TAB, flip

chip, or optical); GaAs IC packaging

(high speed packaging considerations)

package electrical issues (reduction of

parasitics and improvements in electrical performances) ; integrating package

design (from die to system, including

assembly and test issues); VLSI package

materials advancements; die-attach solutions for large chips; new failure

mechanisms in VLSI packaging. [Contact:

George G. Harman, (301) 975-2097]

September 16-18 (Gaithersburg, MD)

Workshop on the Role of Optical Sensors

in Power Systems ' Voltage and Current

Measurements. This Workshop is sponsored by NBS, the Bonneville Power

Administration ( BPA ) , the Electric Power

Research Institute (EPRI), and the

Empire State Electric Energy Research

Corporation (ESEERC) and is intended for

research and development engineers in

utilities and in companies that supply

equipment to the utility industry. The

objective of this workshop is to identify anticipated opportunities for

improved measurement techniques that

should arise as power systems individually and collectively evolve to meet the

needs of the 1990s. Presentations will

stress the design and testing of optical

systems for 60-Hz voltage or current

measurement; the interfacing of electronic or optical components with existing metering and control systems; opportunities for new measurement hardware

resulting from increased automated control of power systems and of the testing

of power system components; and optical

techniques for the measurement of electric and magnetic fields in power systems or system components. The results

of an NBS study evaluating optical techniques for power-system electrical measurements and carried out in agreement

with BPA, EPRI, and ESEERC will be presented as an invited keynote. [Contact:

Raymond S. Turgel, (301) 975-2420 or Robert E. Hebner, (301) 975-2403]

September 22-25 (Boulder, CO)

Noise Measurement Seminar. This fourday course is presented and hosted by

the Electromagnetic Fields Division in

cooperation with representatives from

industry and the NBS Time and Frequency

Division. It is intended for practicing

noise metrologists and technical mana-
CEEE Technical Progress Bulletin - July 1987 Page 2

1

1 987 CEEE Calendar (cont'd.)

gers responsible for systems in which

accurate measurements of thermal and

phase noise are important. Attendees

will learn the most important precautions to take in making accurate noise

measurements and will receive a set of

notes that are suitable for use in solving precision noise measurement problems. Course topics include reference

thermal noise sources; thermal noise

measuring systems and techniques; phase

noise; and the problems of measuring

thermal noise in passive components,

amplifiers, and communication systems.

The course design combines formal lectures on theory presented by NBS staff

and industry experts with demonstrations

in NBS laboratories and demonstrations

of commercial equipment. A special

feature of the Seminar is the opportunity each day for attendees to share

their experiences in solving specific

problems or their insights on practical

noise measurement issues through short

presentations to the assembled group.

Time is scheduled for group discussions

of these presentations and other topics

raised by the Seminar. [Contact: Sunchana Perera (303) 497-3546]

October 26-28 (Boulder, CO)

Symposium on Optical Materials for High

Power Lasers (Nineteenth Boulder

Damage Symposium). This Symposium is

cosponsored by the National Bureau of

Standards, the American Society for

Testing and Materials, the Air Force

Office of Scientific Research, the Office of Naval Research, and the Defense

Advanced Research Projects Agency and

constitutes a principal forum for the

exchange of information on the physics

and technology of materials for highpower lasers.

Topics to be discussed include new materials, bulk damage phenomena, surface

and thin-film damage, design considerations for high-power systems, and fundamental mechanisms of laser-induced

damage. Proceedings of the Symposium

will be published (Note: The collection

of Symposium proceedings contains information on optics for all aspects of

high-power/high-energy lasers, including

environmental degradation, durability,

fabrication, material growth and deposition processes, and testing). [Contact:

Susie A. Rivera (303) 497-5342]

December 10-11 (Gaithersburg, MD)

Power Semiconductor Devices Workshop.

This Workshop, sponsored jointly by IEEE

and NBS, is intended to bring together

for interactive participation those

actively working in the field of power

semiconductor devices. It will be held

in conjunction with the 1987 IEEE International Electron Devices Meeting in

Washington, DC. Four specific topic

areas have been selected, based on the

response to a questionnaire sent to over

200 power device researchers worldwide.

They are: power and high voltage

integrated circuits, discrete devices,

device modeling, and packaging. Attendees are expected to be prepared to

contribute to the development of re- sponses to specific questions that

arise in the context of the particular

topic areas; a final schedule identifying the topic areas should be available at the end of October. [Contact:

David L. Blackburn, (301) 975-2053]

1988 CEEE Calendar

February 10-12 (San Diego, CA)

IEEE Semiconductor Thermal and Temperature Measurement Symposium. This

fourth annual SEMI-THERM symposium

is sponsored by the Components, Hybrids,

and Manufacturing technology Society of

IEEE in cooperation with NBS and constitutes an international forum for the

presentation of new developments in, and

applications relating to, generation and

removal of heat within semiconductor

devices and measurement of junction

temperatures experienced in various

applications and environments. Major

SEMI-THERM topic areas include thermal

measurements, thermal characterization,

applications, and computations and
Page 22 CEEE Technical Progress Bulletin - July 1987

1 988 CEEE Calendar (cont'd.

)

software.

The program includes keynote speakers,

technical presentations, tutorial sessions, workshops, and an exhibit. In

addition, the Semiconductor Equipnent

and Materials Institute has scheduled in

conjunction with SEMI-THERM a meeting of

its Thermal Measurements Task Force, to

which attendees are invited. [Contact:

Frank F. Oettinger, (301) 975-2054]

May 11-13 (Los Angeles, CA)

Intersociety Conference on Thermal

Phenomena in Fabrication and Operation

of Electronic Components. This Conference is sponsored by the Components,

Hybrids, and Manufacturing Technology

Society of the IEEE, in cooperation with

ASME Committee K-1 6 on Heat Transfer and

MBS. It is intended to provide an interdisciplinary forum for exploring

the progress made in understanding,

analyzing, and modeling thermal transport processes and thermally induced

failures in the fabrication, assembly,

and use of logic, memory, and datastorage systems. Major topic areas

covered are 1) processing and fabrication, including state-of-the-art semiconductor crystal growing techniques;

thermal stress in wafers, chips, substrates, PC boards, and joints; and

encapsulant behavior with respect to

solidification, outgassing, mechanical

properties, and water vapor diffusion

and absorption; 2) packaging technology,

including means for cooling components

from cryogenic to high temperatures and

reliability as affected by failure

mechanisms such as dopant migration and

interme tallic growth; and 3) peripheral

equipment, including data storage in

both magnetic and optical media and

thermal issues in dot-matrix and thermal

printer heads. The conference is being

held in conjunction with the Electronics

Components Conference (May 9-11) at the

same site. [Contact: Frank F. Oettinger, (301) 975-2054]

Planned

Combined Short Course on Optical Fiber

and Laser Measurements. [Contact:

Aaron A. Sanders, (303) 497-5341]

Early fall (Boulder, CO)

Fiber Optics Symposium. [Contact:

Aaron A. Sanders, (303) 497-5341]

Late fall (Boulder, CO)

Symposium on Optical Materials for High

Power Lasers (20th Boulder Damage

Symposium). [Contact: Aaron A.

Sanders, (303) 497-5341]

CEEE SPONSORS

National Bureau of Standards

Department of Defense

Defense Nuclear Agency; Defense

Advanced Research Projects Agency;

National Security Agency;

Combined Army/Navy/ Air Force

Calibration Coordination Group

U.S. Air Force

Newark Air Force Station; Rome Air

Development; Space & Missile

Organization; Hanscom Air Force Base;

Wright-Patterson Air Force Base

U.S. Army

Aviation System Command; Fort

Belvoir; Fort Monmouth; Harry Diamond

Laboratories; Materials & Mechanics

Research; Strategic Defense Command

U.S. Navy

Naval Surface Weapons Center; Naval

Ocean Systems Center; Naval Ordnance

Systems Command; Naval Air Test

Center; Ordnance Disposal Technology

Center; Weapons Support Center/Crane;

Office of Naval Research; Naval Air

Engineering Center

Department of Energy

Energy Systems Research; Fusion

Energy; High Energy & Nuclear

Physics; Bonneville Power

Administration

Department of Justice

Law Enforcement Assistance

Administration

Nuclear Regulatory Agency

Department of Treasury

Bureau of Engraving and Printing

Department of Transportation

National Highway Traffic Safety

The Charles Stark Draper Laboratory

International Copper Research

Association

Sandia National Laboratories

University of California

Los Alamos Scientific Laboratory

Early summer (Vail, CO)

.
NBS-114A (REV. 2-80

U.S. DEPT. OF COMM. BIBLIOGRAPHIC DATA

SHEET (See instructions)

4. TITLE AND SUBTITLE

PUBLICATION OR

REPORT NO. NBSIR 87-3589

2. Performing Organ. Report NoJ 3. Publication Date July 1987

Center for Electronics and Electrical Engineering Technical Progress Bulletin Covering

Center Programs, January to March 1987, with 1987 CEEE Events Calendar

5. AUTHOR(S)

E. Jane Walters, compiler

6. PERFORMING ORGANIZATION (If joint or other than NBS, see instructions) 7. Contract/Grant No. NATIONAL BUREAU OF STANDARDS -

U.S. DEPARTMENT OF COMMERCE

GAITHERSBURG, MD 20899

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City. State, ZIP)

. Type of Report & Period Covered

January-March 1987

10. SUPPLEMENTARY NOTES

All technical information included in this document has been approved for publication

previously.

J Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bi bl iography or literature survey, mention it here)

This is the eighteenth issue of a quarterly publication providing information on the

technical work of the National Bureau of Standards Center for Electronics and

Electrical Engineering. This issue of the CEEE Technical Progress Bulletin covers

the first quarter of calendar year 1987. Abstracts are provided by technical area

for both published papers and papers approved by NBS for publication.

12.

KEY WORDS (S/x to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolon s) antennas; electrical engineering; electrical power; electromagnetic interference;

electronics; instrumentation; laser; magnetics; microwave; optical fibers; semiconductors; superconductors

13. AVAILABILITY 14. NO. OF

PRINTED PAGES

[X^Unl imited

| | For Official Distribution. Do Not Release to NTIS 26

1 Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402. 15. Price

[X^Order From National Technical Information Service (NTIS), Springfield, VA. 22161 $11.95

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U.S DEPARTMENT OF COMMERCE

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GAITHERSBURG, MD 20899

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KEY CONTACTS:

Center tte adquarters (720) Director, Mr. Judson C. French (301) 975-2220

Deputy Director, Mr. Robert I. Scace (301) 975-2220

Electrosystems Division (722) Chief, Dr. Oskars Petersons (301) 975-2400

Electromagnetic Fields Division (723) Chief, Dr. Ramon C. Baird (303) 497-3131

Electromagnetic Technology Division (724) Chief, Dr. Robert A. Hamper (303) 497-3535

Semiconductor Electronics Division (727) Chief, Mr. Frank F. Oettlnger (301) 975-2054

INFORMATION:

For additional Information on the Center for Electronics and Electrical Engineering, write or call:

Center for Electronics and Electrical Engineering

National Bureau of Standards

Metrology Building, Room B-358

Gaithersburg, MD 20899

Telephone (301) 975-2220