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iMuoin

Center for Electronics and

Electrical Engineering

Technical

Progress

Bulletin

Covering Center Programs,

April - June 1985 with

1986 CEEE Events Calendar

December 1985

U.S. Department of Commerce

National Bureau of Standards

National Engineering Laboratory

Gaithersburg, Maryland 20899

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INTRODUCTION TO DECEMBER 1985 ISSUE OF THE CEEE TECHNICAL PROGRESS BULLETIN

This is the eleventh 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

second quarter of calendar year 1985.

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 Unpublished papers appear under the subheading "Released for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 telephone number of the individual to

contact for more information on the topic; unless otherwise noted, this person is the

first author. This issue also includes a calendar of Center conferences and workshops now planned for fiscal year 1986, an announcement of recently issued standard

reference materials, and 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 (formerly the

Semiconductor Materials and Processes and Semiconductor Devices and Circuits Divisions) in Gaithersburg, MD, and the Signals and Systems Metrology Program, carried

out oy tne 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

tor 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) 921-3357.

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 20.

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.
CEEE Technical Progress Bulletin - December 85 Page 1

TABLE OF CONTENTS

INTRODUCTION ......... inside front cover

SEMICONDUCTOR TECHNOLOGY PROGRAM

Silicon Materials . ....

Analysis Techniques ..... 2 Gallium Arsenide Materials 3 Power Devices 3 Integrated Circuit Test Structures . 4

Process and Device Modeling 5 Radiation Effects

SIGNALS AND SYSTEMS METROLOGY PROGRAM

FAST SIGNAL ACQUISITION, PROCESSING, 6 TRANSMISSION 7

Waveform Metrology . 7 Cryoelectronic Metrology ..... . 9

Antenna Metrology 10

Optical Fiber Metrology 10

Electro-Optic Metrology .... 11 Other Fast Signal Topics 11

ELECTRICAL SYSTEMS 13

Power Systems Metrology 13

Pulse Power Metrology 15

Superconductors 15

Magnetic Materials and Measurements 17

Other Electrical Systems Topics ..... 18

1 986 CEEE CALENDAR 18

RECENTLY ISSUED STANDARD REFERENCE MATERIALS 19

SPONSOR LIST 2 0

KEY CONTACTS IN CENTER, CENTER ORGANIZATION back cover
Page 2 CEEE Technical Progress Bulletin - December 85

SEMICONDUCTOR TECHNOLOGY PROGRAM

Silicon Materials

Released for Publication

Forman, R.A., Bell, M.I., Myers, D.R.,

and Chandler-Horcwi tz , D. , The Raman

Spectrum of Carbon in Silicon.

Raman spectroscopy is used to characterize carbon-doped silicon samples prepared by ion implantation and pulsed

laser annealing. Sharp lines are observed in the Raman spectra due to the

1

C local mode at 604 ± 1 cm

and the

1

3

C local mode at 589 ± 1 cm" 1

. At the

highest carbon densities, these local

modes broaden considerably. Identical

spectra are obtained from a given carbon

implant whether it is annealed using a 10-ns pulsed ruby laser or a 1-ys pulsed

rhodium-6G dye laser. It is shown that

Raman spectroscopy has sufficient sensitivity to detect striated carbon distributions in as-grown commercial silicon.

Finally, at high carbon density in the

implanted and laser-annealed samples, a disorder-induced first-order Raman spectrum is observed produced by the mass defect of the subs ti tutional carbon.

[Contact: (301) 921-3786]

Mayo, S., Lowney, J.R., and Bell, M.I.,

Evidence of Lattice Relaxation in

Platinum-Doped Silicon, to be published in the Proceedings of the Materials Research Society 1985 Spring

Meeting, San Francisco, CA, April 15-

1 8, 1985.

The photoionization cross section of the

platinum-acceptor level in silicon was measured (in relative units) as a function of photon energy. Capacitance

transients due to electron emission from

this level were studied in a p

+n gated

photodiode at temperatures of 40, 60,

and 80 K. Measurements were made over

the wavelength range of 2 to 5 ym with

lignt from a prism monochromator with a constant bandpass of 10 meV. The platinum density in the diode was about 10 14

O cm--’, providing a ratio of deep to shallow (phosphorus) levels of about 0.1.

The data are in good agreement with the

Ridley-Amato lattice-coupling model when

a Huang-Rhys parameter of S = 0.3 is

used, corresponding to a Frank-Condon

shift of 15 meV if an average phonon

energy of 50 meV is assumed. The electronic energy of the acceptor level was

226 ± 5 meV belcw the conduction band,

independent of temperature and in agreement with previous studies of thermal

ionization. The present results provide

the first clear experimental evidence of

lattice relaxation associated with a deep level in silicon. However, the

observed Huang-Rhys parameter is smaller

than the theoretical estimates of

Lowther (S = 1), suggesting that multiphonon emission may not be the only

mechanism for carrier recombination

involving this level.

[Contact: (301) 921-3786]

Analysis Techniques

Released for Publication

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

Errors in Quantitative FT-IR Spectroscopy, to be published in the Proceedings of the 1985 International Conference on Fourier and Computerized IR

Spectroscopy, Proc. SPIE - The International Society for Optical Engineering,

P.0. Box 10, Bellingham, WA 98227-0010

[paper given at Conference, Ottawa,

Ontario, June 24-28, 1985].

Analog- to-digital converters (ADCs) are

the interface between the analog data

actually collected by a Fourier transform infrared (FT-IR) spectrophotometer

and the digital computer which processes

these data. In the typical case of

absorption spectra obtained using a broadband source, interferograms with a very wide dynamic range (typically on

the order of 106 :1) are required in

order to produce spectra with adequate

signal- to-noise ratios. This is a very

demanding application, especially for a high-speed ADC. A numerical model of the

effect of ADC errors, of ±1 least significant bit (LSB) shows that they can
CEEE Technical Progress Bulletin - December 85 Page 3

Analysis Techniques , cont'd.

nificant bit (LSB) shows that they can produce errors as large as 50% on the

height of peaks in an absorbance spectrum at low signal levels. This result

is consistent with our experimental observations. We tested four ADC circuit

beards (all the same model) in our FT-IR

spectrometer. At low signal levels, the

disagreement between peak heights in

spectra collected using the different

ADC boards ranged as high as 30%, even

though none of them produced the lowwavenumber distortions characteristic of

inadequate ADC performance. The static

transfer characteristics of each of the

ADCs was determined using an automated

test facility at the National Bureau of

Standards. These tests showed that the

boards produced errors ranging only up

to 2 LSBs , in qualitative agreement with

our numerical model.

[Contact: (301) 921-3786]

Recently Published

Forman, R. A., and Mayo, S., In Situ

Alignment for X-Ray Typography, J. Appi. Crystallography, Vol. 18, pp.

1 06-1 09 ( 1 985)

A simple method for in situ alignment of

samples in a double-crys tal x-ray topography system is described. This method

permits a specific crystallographic axis

to be made coincident with the sample

rotation axis used to set the Bragg

angle. Surface reflections from approximately orthogonal crystallographic

planes are required, and tables of such

planes suitable for alignment of cubic

crystals are given. This procedure

allows rapid setup tor the other accessible surface reflection or transmission

topographs.

[Contact: (301) 921-3786]

Gallium Arsenide Materials

Recently Published

Imhotf, E.A., Bell, M.I., and Forman,

R.A., Hot Photoluminescence in Beryllium-Doped Gallium Arsenide, Solid

State Communications, Vol. 54, No. 10,

pp. 845-848 (1985).

Hot photoluminecence in GaAs:Be is re- ported for the first time. The emission

from a sample with p = 6.5 x 10 16 cm3

at 10 K consists of a shoulder at 1.803

± 0.002 eV followed by a series of broad

peaks at 1.781, 1.742, 1.704, 1.666, and

1.628 eV (all ±0.003 eV) . Analysis of

the results supports a decay model involving hot electron-acceptor recombination and implies an L-r splitting of

320 ± 4 meV in the conduction band at

0 K.

[Contact: Michael I. Bell, (301)

921-3786]

Power Devices

Recently Published

Blackburn, D.L. , Turn-Off Failure of

Power MOSFETs , Proceedings of the

1985 IEEE Power Electronic Specialists

Conference, Toulouse, France, June

24-28, 1985, pp. 429-435.

Experimental results of the failure of

power MOSFETs during turn-off are discussed. It is shown that the electrical

characteristics of these devices during

failure are identical to those of a bipolar transistor undergoing second

breakdown. Other comparisons of the

power MOSFET failure and bipolar second

breakdown are made. A nondestructive

measurement system is used allowing

repeated measurements of the failure

characteristics as a function of various

parameters to be made on single devices.

It is shown that practical, commer power MOSFETs do not fail as a result t dV(DS)/dt currents. Drain v> ] a< ; . .iterates up to 22 V/ns were stud

measurements show th.it th*- d , i , . : •

t at which failure occurs increas

temperature, the cri tica 1 currerj ti above

which failure occurs decrease>8 with

temperature, and the ma gni tude of the

load inductance has no e f f ec

t

on the
Page 4 CEEE Technical Progress Bulletin - December 85

Power Devices , cont'd.

failure. The results of this study are consistent with the theory that activation of the parasitic bipolar transistor

initiates the power MOSFET failure.

[Contact: (301) 921-3621]

Integrated Circuit Test Structures

Released for Publication

Lie, L. , Pramanik, D. , Saxena, A.N. , Mazer, J.A., and Linholm, L.W., Contact Resistance of A£-1%Si-0.5%Cu and

AJt/TiW/PtSi Metallization,, to be

published in the Proceedings of the

1985 IEEE VLSI Multilevel Interconnection Conference, Santa Clara, CA, June

24-26, 1985.

The specific contact resistivity, p c , has been measured using six-terminal

Kelvin contact resistor test structures

with contacts of varying sizes. Values

of p c were determined for A£-1%Si0.5%Cu metallizations to n

+ and p+ silicon junctions having different surface

concentrations, CQ

. The magnitude of

p c was found to decrease with increasing CQ

. Values of p c were also

determined for PtSi/TiW/A£ contact metallizations to n

+ and p

+ and were found

to be at least two times lower than that

for A£-Si metallization. Also, the

variation of p c across the wafer for

PtSi was found to be less than that for

AJ£-Si. This indicates that PtSi/TiW/A£

metallizations offer advantages when

compared to At-Si metallization and can contribute to improved performance of

future VLSI circuits.

[Contact: Mazer (301) 921-3801]

Schafft, H.A., and Saxena, A.N. , Electromigration Test Methodology and Characterization, to be published in the

Proceedings of the 3d IBM Electromigration Symposium, Poughkeepsie, NY, April

1, 1985.

The accuracy of electromigration characterizations of metallizations may be

affected significantly by the design of

the electromigration test structure and

by the conditions and procedures used in

testing these structures. This is shown

with a thermal analysis of a straightline test structure and its packaging.

The analysis uses a thermal model for an electromigration test structure from

which equations are derived to calculate

the temperature profile along the structure. It also uses experimental evidence to validate the thermal model and

the use of a series of thermal resistance and capacitance networks to model

the heat flow from the metallization

through the silicon chip, package, and

heat sink, and on to the oven environment.

[Contact: (301) 921-3801]

Recently Published

Roenker, K.P. , Harner, B.L. , and Linholm, L.W., An NMOS Test Chip for

Instruction in Semiconductor Parameter

Measurements, Proceedings of the

Sixth Biennial University/Government/

Industry Microelectronics Symposium,

Auburn, AL, June 1 1-13, 1985, pp.

100-105.

This paper describes an NMOS test chip,

NBS-40, designed for use in a graduatelevel course in the measurement of semiconductor parameters using test structures. The rationale and objectives of

a parameter measurements course are discussed and the organization and re- sults of a course offered at the University of Cincinnati are described. The

test chip layout and test structures are

briefly described and parameter measurements using the test structures are discussed. An NBS technical report

describing the test chip has been prepared and is available as a student

reference. Examples of recent measure- ment results obtained on chips fabricated through the MOSIS service are provided to demonstrate the functionality of the chip.

[Contact: Loren W. Linholm, (301)

921-3801]

Schafft, H.A., Grant, T.C., Saxena,

A.N. , and Kao, C.Y. , Electromigration
CKEE Technical Progress Bulletin - December 85 Page 5

IC Test Structures , cont'd.

and the Current-Density Dependence,

Proceedings of the International

Reliability Physics Symposium, Orlando,

FL, March 26, 1985, pp. 93-99.

The empirical expression used to predict

metallization resistance to electromigration failure involves the current

density to a power of n. A value for n of 1.5 was obtained from stressing un- passivated Al-1% Si metallization test

structures over a range of current densities of from 0.5 to 2.5 MA/cm2 . The

steps taken to ensure an accurate estimate of the metallization stress conditions of temperature current density to

obtain this value are described in detail.

[Contact: (301) 921-3801]

Process and Device Modeling

Released for Publication

Albers, J. , Monte Carlo Calculation of

One- and Two-Dimensiona1 Particle and

Damage Distributions for Ion-Implanted

Dopants in Silicon, to be published

in a joint issue of the IEEE Transactions on Electron Devices and ComputerAided Design.

The two-dimensional distributions of

particles, primary damage, Frenkel

pairs, and electronic and nuclear energy

loss were calculated for implantation of

a line source into silicon targets by

using the TRIM Monte Carlo code. These

allowed for the calculation of the onedimensional distributions of these quantities for implantation into unmasked

targets. The two-dimensional distributions of particles and Frenkel pairs for

implantation past a mask edge were con- structed by means of superposition. The

results are important for understanding

the mass, energy, and dose dependence of

implantation and the associated displacement damage.

[Contact: (301) 921-3621]

Bennett, H.S., Gaitan, M. , Roitman, P. , Russell, T.J., and Suehle, J.S.,

Modeling MOS Capacitors to Extract

Si-Si0

2 Interface Trap Densities in

the Presence of Arbitrary Silicon Doping Profiles.

The MOS capacitor model in SEDAN has

been modified to include the effects of

an energy dependent Si-Si0

2 interface

trap density and arbitrary silicon substrate doping profiles. These modifications have been used to calculate the

quasi-static C-V characteristics of MOS

capacitors and to compare them with

those measured by the Kuhn technique for

as-received and for gamma-irradiated pwell and n-type silicon MOS capacitors.

The average substrate doping is obtained

from high frequency C-V curves. For the

n-type substrate, the dopant redistribution was estimated with SUPREM II.

Experimental and theoretical C-V curves were made to agree by varying the voltage offset due to fixed oxide charge and

both the magnitude and the energy distribution of interface trapped charge.

The distributions of interface traps

which gave the best fits between experiment and theory have peaks near mid gap

for the p-well and n-type silicon MOS

capacitors.

[Contact: (301 ) 921-3621]

Wachnik, R.A., and Lowney, J. R., A

Model for the Charge-Pumping Current

Based on Small Rectangular Voltage

Pulses.

A charge -pumping current results from

recombination associated with the Si

Si interface traps under the gate ( MOSFET when a voltage pulse is applied

to the gate. A model is proposed w: predicts this current as a f < ; n of

the frequency, amplitude, and aw:

voltage of pulses with pe ;>eak

amplitudes less than the 'i i t between the flatband and rnwr

voltages and with pulse trai ns fast

enough so that negligible r emission occurs during th- tr
Page 6 CEEE Technical Progress Bulletin - December 85

Process & Device Modeling , cont'd.

The model is based on Shockley-Read-Ha 11

traps segregated by energy and capture

cross section into traps which capture

only and traps which tend to emit before

capture. It predicts the dominant

behavior of the measured current, and,

with the inclusion of surface potential

fluctuations and a distribution of cross sections it agrees very well with

experiment. Thus, the charge pumping

current due to these small rectangular

pulses can be used to determine the

density, the electron capture cross

section, and the hole capture cross section of interface traps near midgap.

[Contact: Jeremiah R. Lowney, (301)

9 21 -3786]

Wilson, C.L. , and Blue, J.L. , Accurate

Current Calculation in Two-Dimensional

MOSFET Models, IEEE Transactions on Electron Devices.

Two-dimensional simulations of MOSFETs are widely used for the design of shortchannel transistors used in VLSI circuits. These models use low-order methods of discretization of solution variables. In this paper, a method of cur- rent calculation is presented which

works with these methods and yields good

accuracy. The method uses integration

of the solution variables, rather than

differentiation, and is similar to applying Ohm's law in two dimensions.

L Contact: (301 ) 921-3621]

Witte, L.C., CSFIT: A FORTRAN Program

for Charge-Sheet Model Fitting of

MOSFET Data, to be published as NBSIR

85-3145.

A FORTRAN program, CSFIT, has been developed for fitting an expression for

the current-voltage (I-V) characteristics of a long-channel MOSFET to ejqperimental I-V curves. The one-dimensional

charge-sheet model developed by Brews

provides the basis for the I-V characteristics. The I-V characteristics

given by this model are optimized with

respect to a set of experimental data

using the flatband voltage and the mobility as the only adjustable parameters. The program is written so that

multiple sets of I-V data can be fit

simultaneously if desired. The user must supply, in specified formats, a current-voltage data file, a device

parameter file, and a starting value

file.

[Contact: Kenneth F. Galloway, (301)

921-3541]

Recently Published

Bennett, H.S., Band Structure and

Density of States Changes for Doped

Gallium Arsenide, paper in NBS

Special Publication 697, OM85, Basic

Properties of Optical Materials, Summaries of Papers [given at the Topical

Conference, Gaithersburg, MD, May 7-9,

1985], pp. 194-197 (April 1985).

Optical absorption measurements on doped

GaAs are interpreted in terms of distorted band structures. Such data provide values for the many-body interactions which are essential in calculations on the operation of lasers and

opto-electronic devices.

[Contact: (301) 921-3621]

Wilson, C.L. , and Blue, J.L. , Semiconductor Measurement Technology:

M0S1 : A Program for Two-Dimensional

Analysis of Si MOSFETs, NBS Special

Publication 400-77 (April 1985).

The MOSI program is a portable FORTRAN

77 program suitable for analysis of

currents and fields in VLSI devices.

The program solves three coupled non- linear elliptic partial differential

semiconductor device equations in two

dimensions. Historically, these equations have been solved using a specialpurpose program, and batch runs on a large, fast computer. We use a generalpurpose program which runs on a large

minicomputer or scientific workstation.

This report discusses the physical formulation of the semiconductor equations

and the methods used to select the solution strategy.

[Contact: (301) 921-3621]
CEEE Technical Progress Bulletin - December 85 Page 7

Radiation Effects

Released for Publication

Galloway, K.F., Wilson, C.L., and Witte,

L.C., Charge-Sheet Model Fitting to

Extract Radiation-Induced Oxide and

Interface Charge.

A method for extracting values of oxide

and interface charge from the currentvoltage (I-V) characteristics of longchannel MOSFETs is described. The onedimensional charge-sheet model developed

by brews provides the basis for the I-V

characteristics. The I-V characteristics given by this model are optimized

with respect to a set of experimental

data for an irradiated device with the

flatband voltage and the mobility the

only free parameters. Simple relationships between these parameters and the

radiation-induced interface and oxide

charge are assumed.

[Contact: (301) 921-3541]

Recently Published

Galloway, K.F., Wilson, C.L. , and Witte,

L.C., MOSFET Electrical Parameter

Extraction from Charge-Sheet Model

Fitting, Proceedings of the Sixth

Bi ennia 1 Unive rs i ty/ Gove r nme n t/ Indu s try

Microelectronics Symposium, Auburn, AL,

June 11-13, 1985, pp. 77-81.

A method for extracting the flatband

voltage and the channel mobility from

the current-voltage (I-V) characteristics of long-channel MOSFETs is described. The one-dimensional chargesheet model developed by Brews provides

the basis for the I-V characteristics.

The I-V characteristics given by this

model are optimized with respect to a set of experimental data with the flatband voltage and the mobility the only

free parameters. A computer program,

CSFIT, has been developed for this purpose. The choice of parameters is usually appropriate for a device subjected

to a stress condition (e.g., hot-carrier

injection or ionizing radiation) . To

illustrate the application of this method and CSFIT, the flatband voltage and

mobility for an n-channel enhancementmode device subjected to ionizing radiation are determined from the I-V curves and the changes of these parameters with

radiation dose are tracked.

[Contact: (301) 921-3541]

FAST SIGNAL ACQUISITION, PROCESSING, AND

TRANSMISSION

Waveform Metrology

Released for Publication

Flach, D.R., Characterization of Waveform Recorders, to be published in

the Proceedings of the Seminar on Digital Methods in Waveform Metrology,

Gaithersburg, MD, October 18-19, 1983,

NBS Special Publication 707.

Transient waveform recorders have been

in use for more than 15 years with no commonly accepted test procedures for

measuring the performance of these instruments with dynamic input signals.

One test procedure that has been increasingly used by manufacturers and

others in recent years involves the

application of steady-state sinusoidal

waveforms to measure the dynamic characteristics of these instruments. These

tests measure integral and differential

linearity errors, missing codes, signalto-noise ratios (effective number of

bits) and aperture uncertainty.

Described are sine wave tests that use non-linear, least-square curve fit procedures to measure the waveform

corder's noise, and thus the siq:

to-noise ratio. This approach yields a "global" description of the recorder's

errors. A sine wave test where the data

are evaluated using a Fast Fburier

Transform is described. This test

particularly useful to measure the 1 1 gral linearity errors of the wave'

recorder. A histogram test :h measures differential linearity .

.. , •. missing codes, is descrih' are given for the above tests. A method

for measuring aperture un • unty

briefly mentioned.
Page 8 CEEE Technical Progress Bulletin - December 85

Waveform Metrology , cont'd.

Two NBS-deve loped test procedures, a single period transient sinusoidal test,

and the voltage-step generator, are also

described, and test results are given.

[Contact: (301) 921-2727]

Kanada, T. , and Franzen, D.L. , Optical

Waveform Measurement by Optical Sampling/Crosscorrelation with a Modelocked Laser Diode.

Optical pulses from a GaAlAs buried

heterostructure (BH) laser diode directly modulated at a frequency f

Q (971.5

MHz ) are mixed in a LiI0

3 crystal with

20 ps wide optical sampling pulses at a frequency of f

Q -10 92 from a second

modelocked, GaAlAs BH laser diode. The

optical signal obtained by sum frequency

mixing in the crystal is observed with a photomultiplier and an oscilloscope.

The original pulse waveform is reproduced clearly with a temporal resolution

of about 20 ps and at a repetition frequency of 10 Hz.

[Contact: (303) 497-5342]

Oldham, N.M., Digital Waveform Synthesis Techniques, to be published in

the Proceedings of the Seminar on Digital Methods in Waveform Metrology,

Gaithersburg, MD, October 18-19, 1983,

NBS Special Publication 707.

The theory of digital waveform synthesis, including hardware implementations

and practical limitations are discussed.

The generation of sinewaves as well as arbitrary waveforms using zero-orderhold and linear-point-connector recon- struction techniques is analyzed. An

NBS-deve loped sinewave generator which

provides a high accuracy (50 ppm) signal

from dc to 50 kHz is also described.

[Contact: (301) 921-2727]

Schoenwe tter, H.K. , Settling Time

Measurements, to be published in the

Proceedings of the Seminar on Digital

Methods in Waveform Metrology,

Gaithersburg, MD, October 18-19, 1983,

NBS Special Publication 707.

Methods are described for measuring the

settling times (STs) and other dynamic

characteristics of D/A converters,

operational amplifiers, and precision

voltage-step generators. The measure- ment of device STs from 5 ps to less

than 20 ns with corresponding accuracies

of 1 ppm and 0.1% is described.

[Contact: (301) 921-2727]

Souders, T.M., Data Converter Test

Methods, to be published in the Proceedings of the Seminar on Digital

Methods in Waveform Metrology,

Gaithersburg, MD, October 18-19, 1983,

NBS Special Publication 707.

Data converter test methods pertinent to

measurement or control instrumentation

applications are reviewed. Methods

ranging from simple manual techniques to

comprehensive fully automated approaches

are discussed for both digital- to-analog

and analog- to-digi tal converters.

Strengths and weaknesses, major applications, and pertinent references are presented for each.

[Contact: (301) 921-2727]

Souders, T.M., Flach, D.R., and Schoenwetter, H.K., Transient Response

Characterization of Waveform Recorders,

to be published in the Proceedings of

the 5th IEEE Pulsed Power Conference,

Crystal City, VA, June 10-12, 1985.

Test methods for characterizing the

transient response of waveform recorders

are presented, together with typical

test results. The methods, based on the use of a precision, programmable step

generator developed at NBS, are suitable

for recorders having up to 10-bit reso- lution and 100-MHz bandwidth.

[Contact: (301) 921-2727]

Stenbakken, G.N. , Dual-Channel Sampling Systems, to be published in the

Proceedings of the Seminar on Digital

Methods in Waveform Metrology,

Gaithersburg, MD, October 18-19, 1983,

NBS Special Publication 707.

Measuring two signals simultaneously
CEEE Technical Progress Bulletin - December 85 Page 9

Waveform Metrology , cont'd.

with a dual-channel sampling system

allows for the calculation of many signal parameters not easily obtained with

single-channel instruments. This paper

concentrates on the use of dual-channel

sampling for the measurement of power

and phase angles. The theoretical relationships are developed between the

sampled data, the measured quantities,

and the error sources. Both hardware

and software errors are described.

Calibration techniques are given for

quantifying many of the error sources.

[Contact: (301) 921-2727]

Turgel, R.S., Phase Angle Standards

and Calibration Methods , to be

published in the Proceedings of the

Seminar on Digital Methods in Waveform

Metrology, Gaithersburg, MD, October

18-19, 1983, NBS Special Publication

707.

Measurement of phase angles in the audio

frequency range is discussed with emphasis on precision phase meters and their

calibration using an NBS-developed Phase

Angle Calibration Standard.

[Contact: (301) 921-2727]

Turgel, R.S., A Precision Phase Angle

Calibration Standard for Frequencies up

to 50 kHz*

A phase angle calibration standard cov- ering a frequency range from 2 Hz to 50

kHz has been designed and constructed.

Digital waveform generation is used to

provide sinusoidal analog outputs having

precisely settable phase angles. Output

voltages are independently adjustable

from 0.5 to 100 volts rms on both channels. An auto-zero feed-back loop com- pensates for differential phase errors

of the output amplifiers.

[Contact: (301) 921-2727]

Cryoelectronic Metrology

Released for Publication

Kautz, R.L. , and Lloyd,

F.L., A Josephson Series Array Voltage Standard at One Volt, to be published in the Proceedings of the 1985

NCSL Workshop and Symposium, Boulder,

CO, July 15-18, 1985.

Josephson voltage standards have long

been limited by their low 1-10 mV output

level. A new method for operating 1000 or more Josephson junctions in series

has produced a practical standard at the

one-volt level. The junction array is

in the form of a microstrip which is

f inline coupled to a waveguide at one end and is terminated at the other end.

The whole circuit is fabricated on a 6

by 1 2 mm silicon substrate. With applied radiation at 72 GHz, the junction

array produces up to 8000 quantized

levels at the voltages nhf/2e. (In the

UoS. 2e/h has an assigned value of

483593.420 GHz/Vnbs*) By selecting

the level, n, and fine tuning the frequency, f, any voltage from 0.1 to 1 .

volts can be obtained. The high output

voltage eliminates the need for a voltage divider and greatly reduces errors

due to thermal voltages. When fully

evaluated, the new standard is expected

to have a precision of a few parts per

billion.

[Contact: (303) 497-3740]

Kautz, R.L., and Macfarlane, J.C.,

Onset of Chaos in the rf-Biased

Josephson Junction.

The onset of chaos in the rf -biased

Josephson junction is studied through

numerical simulations. It is shown that

the chaotic region predicted by the

method of Melnikov spans only a narrow region of rf amplitudes and consists of

weakly chaotic solutions which na phase lock with the rf bias. The

experimentally observed thr» shc Id

chaos is shewn to coincide wi th *-he onset of unlocked chaotic behavior at

higher rf amplitudes.

[Contact: (303) 497-3391 ]

McDonald, D.G. , and Frederick , 'J.V.,

Amplification by a Voltage Locked Array

Hamilton, C.A., of Josephson Junctions.
Page 1

0

CEEE Technical Progress Bulletin - December 85

Cryoelectronic Metrology , cont'd.

We have studied a new type of Josephson

junction amplifier which is based on a two-junction array; the junctions are mutually phase locked at the Josephson

self -oscillation frequency. With this

frequency at 82 GHz, the voltages of the

junctions remain equal (locked) for a bias current range as large as 60% of

the critical current. Over a much

smaller bias range, with an applied

signal frequency of 1 kHz, a smallsignal power gain of 19 dB was measured,

accompanied by a negative resistance

input impedance. This performance is

consistent with a quasi static theory of

the amplifier.

[Contact: (303) 497-51 13]

Recently Published

Zimmerman, J. E. , Design of Cryocoolers

for Microwatt Superconducting Devices,

Proceedings of the Third Cryocooler

Conference, Boulder, CO, September

17-18, 1984, pp. 2-9, NBS Special Publication 698 (May 1985).

The primary applications of the cryocoolers considered here are for cooling

various Josephson devices such as SQUID

magnetometers and amplifiers, voltage

standards, and microwave mixers and

detectors. The common feature of these

devices is their extremely low inherent

bias power requirement, of the order of

1

0

-7 W (or sometimes much less) per

junction. This provides the possibility, not yet fully exploited, of designing compact, lew -power cryocoolers for

these applications, the design criteria

being totally different from those of

any cryocoolers presently available.

Several concepts have been explored and

a number of laboratory model cryocoolers

have been built. These include lowpower non-magnetic regenerative machines

of the Stirling or Gif ford- McMahon type,

three- or four-stage Joule-Thorns on machines, liquid-helium dewars with integral small cryocoolers to reduce the

evaporation rate, and liquid-helium

dewars with integral continuously or

intermittently operated small helium

liquefiers to permit operation of cryogenic devices for indefinite time

periods.

[Contact: Richard L. Harris, (303)

497-3901]

Antenna Metrology

Recently Published

Kanda, M. , Transients in a Resistively

Loaded Loop Antenna, Proceedings of

the 1984 International Symposium on Electromagnetic Compatabili ty [IEEE EMC

Society], Tokyo, Japan, October 16-18,

1984, pp. 286-290.

Transient characteristics of a loop

antenna loaded uniformly with a resistive material are analyzed. The current

distribution of the antenna is obtained

by the use of the Fourier series expansion technique. It is found that the

distortion of the transient waveforms

due to a resonance of a loop antenna can

be reduced and the received transient

waveforms can be tailored by resistive

loading.

[Contact: (303) 497-5320]

Optical Fiber Metrology

Released for Publication

Danielson, B.L . , Optical Time-Domain

Reflectometer Performance

From a researcher's as well as a user's

point of view, it is highly desirable to

adopt a common basis for specifying

optical time-domain ref lectometer performance parameters. This paper proposes some procedures and test methods

which permit these devices to be characterized in a consistent way. We also

describe passive test fixtures which may

facilitate measurements of dynamic range

and other reflectome ter properties.

[Contact: (303) 497-5620]

Danielson, B.L., Optical Time-Domain

Reflectometer Signal Enhancement Using

Extended Probe Pulse Methods.
CEEE Technical Progress Bulletin - December 85 Page 1

3

Other Fast Signal Topics , cont'd.

turns, deformation, and ferrite defects

is described.

[Contact: (303) 497-3641]

Leedy, T.F., An Approach to ATE Calibration Via Performance Verification at

the System Interface, Proceedings of

the 1985 Measurement Science Conference, Sunnyvale, CA, January 17-18,

1 985, pp. 198-201.

A method of verifying the performance of

automatic test equipment (ATE) in its

normal operating environment and configuration is presented as the best approach to achieving an overall system

calibration. The method consists of the

transport of well-characterized signal

sources to the ATE station and the application of these electrical stimuli

directly to a well-defined electrical

interface on the test station. Data are

presented on typical accuracies that

have been obtained on limited parameters

and ranges during the testing process,

using calibrated commercial equipment.

[Contact: (301) 921-2727]

Sorrells, J.R., Palla, J.C., Meiselman,

B., and Oravec, B.A., Electrical and

Electronic Metrology: A Bibliography

of NBS Electrosystems Division's Publications, NBS List of Publications 94

(March 1 985) .

This bibliography lists the publications

of the Electrosystems Division, Center

for Electronics and Electrical Engineering, NBS, and of its predecessor sec- tions for the period January 1968 to

March 1984. A brief description of the

Division's technical program is given in

the introduction.

[Contact: (301) 921-2727]

ELECTRICAL SYSTEMS

Power Systems Metrology

Released for Publication

Hebner, R.E. , Kelley, E.F., FitzPatrick,

G. J. , and Forster, E.O. , Prebreakdown

Cathode Processes in Liquid Hydrocarbons.

Measurements are presented of the initiation of prebreakdown streamers at a point cathode in liquid hydrocarbons.

Using a computer implementation of the

method of images, the electric field is

computed for selected geometries to

demonstrate that the field strengths in

the vicinity of these streamers are probably high enough so that electron

multiplication processes can occur. In addition, it is shown that the primary

streamer moves at about the same velocity that a solvated ion would move if it

were placed in the electric field.

[Contact: (301) 921-3121]

McKnight, R.H., Operation of an Ion

Counter in the Ground Plane Under a Monopolar Line, to be published in

the Proceedings of the 23rd Hanford

Life Sciences Symposium, Hanford, WA,

October 22-24, 1985.

Studies have been made of the operation

of an ion counter with the inlet located

in the ground plane near a monopolar

line. Electric field values at the

ground plane ranged between 14.8 kV/m

and 29.8 kV/m, while ion current densities varied from 0.1 to 0.43 yA/m? . An

observed variation in measured ion density with volumetric flow rate through

the counter appears to be predominantly

due to losses in the duct between the

ground plane opening and the ion count. -r inlet.

[Contact: (301 ) 921-31 21]

Misakian, M., High Voltage Divider and

Resistor Calibrations, to be published as NBS Technical Note TN-1215.

An NBS calibration service for determi n ing the ratio of high-voltage de- ers and the resistance of high-VOlt

resistors is described. Calibr e i are performed with a Wheatstone bri :;>• apparatus with a simple guard .y

•

• . Sources of systematic error ar- . h

• fied and methods for character i /. i r i

•
Page 1

CEEE Technical Progress Bulletin - December 85

Power Systems Metrology , cont'd.

NBS standard high-voltage resistors are discussed. Ratio and resistance values can be determined between the voltages

of 10 kV and 150 kV with an uncertainty

of less than ±0.01%.

[Contact: (301) 921-31 21]

Oldham, N.M., and Petersons, 0. , Calibration of Standard Wattmeters Using a Capacitance Bridge and a Digital Generator.

A method tor calibrating high-accuracy

wattmeters is described. The technique

is a modification of a previously described approach that utilizes a power

bridge based on a current comparator.

In such a bridge the test current of the

wattmeter is balanced with a known cur- rent that is proportional to the test

voltage. The measurement circuit described employs a high-voltage capacitance bridge in place of a special cur- rent comparator that was used in the

previous system. High sensitivity and

large ratios of the capacitance bridge

enable using high impedances, such as stable gas-dielectric capacitors and

resistors having low power dissipation,

for the generation of reference currents. The voltage on the standard

impedances is adjusted with inductive

dividers to obtain any power factor

between zero and one, lead and lag. A

digitally synthesized dual-channel signal source serves as a stable source of

voltage and current, and thus of "phantom" power.

[Contact: (301) 921-2727]

Ramboz , J.D., and Petersons, 0.

,

Emerging New Requirements for Electric

Power And Energy Measurements , to be

published in the Proceedings of the

1985 NCSL Workshop and Symposium,

Boulder, CO, July 15-18, 1985.

Advances in electronic instrumentation

technology have brought greater stability and precision to transducers that are utilized for measuring electric

power and energy. An advantage of instruments based on electronic transducers is that they can be readily adapted

to the measurement of other quantities

such as current, voltage, reactive and

apparent power, power factor, demand,

time-of-day readings, etc. Hie in- creases in the cost of energy during the

past decade have stimulated the acceptance of new instrument technology by

the users associated with the electric

power industry. The electronic instruments have especially found acceptance

in metering installations for large

loads and at interchange points between

utilities. Modern instruments, because

of their accuracy capabilities, are also

advantageous in those applications where

the efficiency of large equipment such

as generators and transformers has to be

measured. A large number of the instruments used as physical standards by the

industry and submitted recently to the

National Bureau of Standards (NBS) for

calibration have been of the electronic

type. The calibration accuracies re- quested from NBS for power and energy

measurements have increased at least

fivefold (uncertainty reduction from

±0.5% to ±0.1%) within the past several

years. Calibrations for different quantities and values are being requested.

These changing calibration requirements

and the response of NBS to meet the

requests of its calibration clientele

are discussed.

[Contact: (301 ) 921-3121]

Recently Published

Hebner, R.E. , Kelley, E.F., Forster,

E.O., and FitzPatrick, G. J. , Observation of Prebreakdown and Breakdown

Phenomena in Liquid Hydrocarbons II.

Non-Uniform Field Conditions, IEEE

Transactions on Electrical Insulation,

Vol. EI-20, No. 2, pp. 281-292 (April

1985)

The prebreakdown and breakdown processes

have been recorded in n-hexane toluene

and Marcol 70, both in a pure state and

with selected impurities. The study was carried out using a point-plane geometry. A low ionization potential addi-
CEEE Technical Progress Bulletin - December 85 Page 1

5

Power Systems Metrology , cont'd.

tive had only a small effect on the

breakdown voltage or the streamer propagation speed but did significantly alter

the shape of the prebreakdown streamer

when the needle was positive, i.e., an

anode. For a negative needle (cathode) , chemical impurities affected the breakdown voltage. Hie significance of these

findings is discussed in detail.

[Contact: (301) 921-3121]

Van Brunt, R.J., Production Rates for

Oxyfluorides S0F

2

, so2 F

2

1 azu^ SOFk in

SF

6 Corona Discharges, NBS Journal of

Research, Vol. 90, No. 3, pp. 229-253

(May-June 1985).

The most abundant, long-lived stable

gaseous species generated by corona

discharges in SF^ gas containing trace

levels of 0

2 and H

2 0 are the oxyfluorides S0F2

, S0

2 F

2

, and SOF^. Absolute

energy and charge rates-of -production of

these and the minor products S02

, OCS,

and C02 have been measured at different

total gas pressures from 100 kPa to 300

kPa and for discharges of different

current, power, and polarity. Oxyfluoride yields for SF

6 /C>

2 mixtures containing up to 10% 02 have also been measured. The results indicate that oxytluonde production is not controlled by

the concentrations of either 0

2 or H

2 0

at levels below about 1%, and the rate

controlling factor is the dissociation

rate of SF

& in the discharge. The discharge current and time dependence of

the production rates are discussed in

terms of gas-phase mechanisms that have

been proposed to explain previous observations of electrical, thermal, and

laser-induced decomposition of SF

& and

SF

6 /0 2 mixtures. Upper limits on the

total SF& decomposition rate in lowcurrent discharges have been estimated.

Details of the chemical analysis procedures are given, and application of the

results to the design of chemical diagnostics for SF

6 -insulated, high-voltage

apparatus is discussed.

[Contact: (301) 921-3121]

Pulse Power Metrology

Released for Publication

McKnight, R.H., Fenimore, C., and

Lagnese, J. , Hie Use of Deconvolution

Methods in Characterizing Electrical

Sensors, to be published in the Proceedings of the 5th IEEE Pulsed Power

Conference, Crystal City, VA, June

10-12, 1985.

Deconvolution methods have been applied

to measurements made with different

electrical sensors including resistive

and capacitive dividers. Deconvolved

and directly measured waveforms have

been compared with good results.

[Contact: (301) 921-3121]

Superconductors

Released for Publication

Fickett, F.R., Research on Practical

Superconductors at NBS, to be

published in the Proceedings of the

Benelux Metallurgy Conference on Superconductors, Brussels, Belgium, May

8-9, 1985.

The National Bureau of Standards is

engaged in a large number of research

programs which have as their goals the

evaluation of various properties of

practical superconductors related to

their application in large-magnet systems. The ability to have standard

data, standard tests, and standard materials for evaluating the primary properties of superconductors and relate 1 measurement systems is essential to th«- increasing international commerce in

these complicated conductors. The NBS

work has concentrated on measurement ; critical current, critical field, .i< losses, and properties of the copper

normally used as a stabilizing mater.

Many parameters must be considered

these investigations. An overview

these research efforts and a self t of recent results are presented. Pa

cular emphasis is given to work per
Page 1 6 CEEE Technical Progress Bulletin - December 85

Superconductors , cont'd.

formed in cooperation with the International Copper Research Association

(INCRA) on properties of oxygen-free

copper.

[Contact: (303) 497-3785]

Goodrich, L.F., Minervini, J.V. , Clark,

A.F., Fickett, F.R. , Ekin, J.W., and

Pittman, E.S., Development of Standards for Superconductors Interim Report, January 1 982-December 1983, to

be published as NBSIR 85-3027.

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

for the critical parameters and other

characterizations of practical superconductors. Progress for the period January 1982 through December 1983 is re- ported. The major effort was the procurement, selection, and certification

of the first superconducting wire for

critical current measurements as a Standard Reference Material ( SRM 1457).

Other work reported here includes:

effect of geometry on current transfer,

lap-joint resistance, and ac losses.

[Contact: (303) 497-3143]

Moreland, J. , and Ekin, J. W., Electron

Tunneling Experiments Using Nb-Sn

"Break" Junctions.

An Nb-Sn filament mounted on a flexible

glass beam can be broken to form an electron tunneling junction between the

fracture elements. Breaking the filament in liquid helium prevents oxidation

of the freshly -ejqposed fracture sur- faces. A sharp superconducting energy

gap in the I-V characteristics measured

at 4 K indicates the formation of a high

quality tunneling barrier between the

fracture elements. The resistance of

the junction between the fracture elements can be adjusted continuously by

varying the surface bending strain of

the beam.

[Contact: (303) 497-5477]

Recently Published

Fickett, F.R . , Standards for Measurement of the Critical Fields of Superconductors, NBS Journal of Research,

Vol. 90, No. 2, pp. 95-113 (March-April

1985) . The origins, definitions, and measure- ment of the various critical magnetic

fields associated with superconductors

are reviewed. The potential need for an ASTM-type standard for the measurement

of these fields is discussed. Measurement techniques as practiced both in

industry and in the national laboratories are reviewed. Extrapolation techniques commonly used to determine the

upper critical fields of the newer materials are evaluated as to their suitability for various applications.

Sources of error in the experimental

determination of critical fields are assessed for the various common techniques. A comprehensive bibliography of

the modern literature on critical field

measurement and interpretation is included.

[Contact: (303) 497-3785]

Goldfarb, R.B., and Clark, A.F., Hysteretic Losses in Nb-Ti Superconductors, J. Appl. Phys. , Vol. 57, No. 1,

pp. 3809-381 1 (1 5 April 1985).

When subjected to transient magnetic

fields, superconductors exhibit losses.

At low frequencies, most of the dissipation is hysteretic. Magnetization was measured in an axial field for eight

multifilamentary Nb-Ti superconducting

wires with different filament sizes and

different ratios of copper to superconductor. The full-penetration field Hp was estimated from the high-field ends

of the hysteresis loops. The estimate

of Hp provides a method to assess the

critical current density Jc . There

was good agreement between measured

losses and those predicted from Hp and

the peak applied field.

[Contact: (303) 497-3650]
CKEE Technical Progress Bulletin - December 85 Page 1

5

Power Systems Metrology , cont'd.

tive had only a small effect on the

breakdown voltage or the streamer propagation speed but did significantly alter

the shape of the prebreakdown streamer

when the needle was positive, i.e., an

anode. For a negative needle (cathode) , chemical impurities affected the breakdown voltage. The significance of these

findings is discussed in detail.

[Contact: (301 ) 921-3121]

Van Brunt, R.J., Production Rates for

Oxyfluorides SOF

2

, S02 F

2

, and SOF^ in

SF

fe Corona Discharges, NBS Journal of

Research, Vol. 90, No. 3, pp. 229-253

(May -June 1985).

The most abundant, long-lived stable

gaseous species generated by corona

discharges in SF

fe gas containing trace

levels of 02 and H

2 0 are the oxyfluorides S0F

2

, S0

2 F

2

, and S0F

4

. Absolute

energy and charge rates-of -production of

these and the minor products S02

, OCS,

and C0

2 have been measured at different

total gas pressures from 100 kPa to 300

kPa and for discharges of different

current, power, and polarity. Oxyfluoride yields for SF

& /0

2 mixtures containing up to 10% 0

2 have also been measured. The results indicate that oxytluonde production is not controlled by

the concentrations of either 0

2 or H2 0

at levels below about 1%, and the rate

controlling factor is the dissociation

rate of SF

& in the discharge. The discharge current and time dependence of

the production rates are discussed in

terms of gas-phase mechanisms that have

been proposed to explain previous observations of electrical, thermal, and

laser-induced decomposition of SF

& and

SF

6 /0 2 mixtures. Upper limits on the

total SF^ decomposition rate in lowcurrent discharges have been estimated.

Details of the chemical analysis procedures are given, and application of the

results to the design of chemical diagnostics for SF^-insulated, high-voltage

apparatus is discussed.

[Contact: (301 ) 921-3121]

Pulse Power Metrology

Released for Publication

McKnight, R.H., Fenimore, C. , and

Lagnese, J. , The Dse of Deconvolution

Methods in Characterizing Electrical

Sensors, to be published in the Proceedings of the 5th IEEE Pulsed Power

Conference, Crystal City, VA, June

10-1 2, 1985.

Deconvolution methods have been applied

to measurements made with different

electrical sensors including resistive

and capacitive dividers. Deconvolved

and directly measured waveforms have

been compared with good results.

[Contact: (301) 921-31 21]

Superconductors

Released for Publication

Fickett, F.R., Research on Practical

Superconductors at NBS, to be

published in the Proceedings of the

Benelux Metallurgy Conference on Superconductors, Brussels, Belgium, May

8-9, 1985.

The National Bureau of Standards is

engaged in a large number of research

programs which have as their goals the

evaluation of various properties of

practical superconductors related to

their application in large-magnet systems. The ability to have standard

data, standard tests, and standard materials for evaluating the primary properties of superconductors and relate 1 measurement systems is essential to the

increasing international commerce in

these complicated conductors. The Ni- work has concentrated on measurement t critical current, critical field, .ic losses, and properties of the copper

normally used as a s tabi 1 iz i ng sateI I l . Many parameters must be considered

these investigations. An overview

these research efforts and a .-i. • of recent results are presented. Pa

cular emphasis is given to work per
Page 1

6

CEEE Technical Progress Bulletin - December 85

Superconductors , cont'd.

formed in cooperation with the International Copper Research Association

(INCRA) on properties of oxygen-free

copper.

[Contact: (303) 497-3785]

Goodrich, L.F., Minervini, J.V. , Clark,

A.F., Fickett, F.R., Ekin, J.W., and

Pittman, E.S., Development, of Standards for Superconductors Interim Report, January 1 982-December 1983, to

be published as NBSIR 85-3027.

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. Ihe goal

is the adoption of voluntary standards

for the critical parameters and other

characterizations of practical superconductors. Progress for the period January 1982 through December 1983 is re- ported. The major effort was the procurement, selection, and certification

of the first superconducting wire for

critical current measurements as a Standard Reference Material ( SRM 1457).

Otner work reported here includes:

effect of geometry on current transfer,

lap-joint resistance, and ac losses.

[Contact: (303) 497-3143]

Moreland, J. , and Ekin, J.W., Electron

Tunneling Experiments Using Nb-Sn

"Break" Junctions.

An Nb-Sn filament mounted on a flexible

glass beam can be broken to form an electron tunneling junction between the

fracture elements. Breaking the filament in liquid helium prevents oxidation

of the freshly-exposed fracture sur- faces. A sharp superconducting energy

gap in the I-V characteristics measured

at 4 K indicates the formation of a high

quality tunneling barrier between the

fracture elements. The resistance of

the junction between the fracture elements can be adjusted continuously by

varying the surface bending strain of

the beam.

[Contact: (303) 497-5477]

Recently Published

Fickett, F.R., Standards for Measurement of the Critical Fields of Superconductors, NBS Journal of Research,

Vol. 90, No. 2, pp. 95-113 (March-Apri

1985) . The origins, definitions, and measure- ment of the various critical magnetic

fields associated with superconductors

are reviewed. The potential need for an ASTM-type standard for the measurement

of these fields is discussed. Measurement techniques as practiced both in

industry and in the national laboratories are reviewed. Extrapolation techniques commonly used to determine the

upper critical fields of the newer materials are evaluated as to their suitability for various applications.

Sources of error in the experimental

determination of critical fields are assessed for the various common techniques. A comprehensive bibliography of

the modern literature on critical field

measurement and interpretation is included.

[Contact: (303) 497-3785]

Goldfarb, R.B., and Clark, A.F., Hysteretic Losses in Nb-Ti Superconductors, J. Appl. Phys. , Vol. 57, No. 1,

pp. 3809-3811 (15 April 1985).

When subjected to transient magnetic

fields, superconductors exhibit losses.

At low frequencies, most of the dissipation is hysteretic. Magnetization was measured in an axial field for eight

multifilamentary Nb-Ti superconducting

wires with different filament sizes and

different ratios of copper to superconductor. The full-penetration field H

p

was estimated from the high-field ends

of the hysteresis loops. The estimate

of Hp provides a method to assess the

critical current density Jc

. There

was good agreement between measured

losses and those predicted from H

p

and

the peak applied field.

[Contact: (303) 497-3650]
CEEE Technical Progress Bulletin - December 85 Page 1

Superconductors , cont'd.

Goldtarb, R.B., and Clark, A.F., Magnetic Hysteresis and Complex Susceptibility as Measures of AC Losses in a Multifilamentary NbTi Superconductor,

IEEE Transactions on Magnetics, Vol.

MAG-21, No. 2, pp. 332-335 (March

1 985) .

Magnetization and ac susceptibility of a standard NbTi superconductor were mea- sured as a function of longitudinal dc

magnetic field. The ac-fie ld-amplitude

and frequency dependences of the complex

susceptibility are examined. The magnetization is related to the susceptibility by means of a theoretical derivation based on the field dependence of

the critical current density. Hysteresis losses, both obtained directly from

dc hysteresis loops and derived theoretically from ac susceptibility and critical current density, were in reasonable

agreement.

[Contact: (303) 497-3650]

Magnetic Materials and Measurements

Released for Publication

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

Fickett, F.R., Flaw Detection with a Magnetic Field Gradiometer, to be

published in the Proceedings of the

NTIAC 15th Symposium on NDE, San

Antonio, TX, April 22-24, 1985.

When eddy currents are induced in a conductor, flaws deflect the eddy

currents 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 tor 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 Interference 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 is

also discussed.

[Contact: (303) 497-3641 ]

Goldfarb, R.B., Rao, K. V. , and Chen,

H.S., Hew Magnetic Phase Diagram of

the Amorphous Pd-Fe-Si Ferroglass Alloy

System.

The magnetic phase diagram of amorphous

Pd rt

-xFe v Si „ „ was examined. The

8 0 A 2 Q peak m the imaginary component of ac susceptibility was used to determine the

ferromagnetic-like/spin-glass transition

temperatures Tfg. It was found that

the Tfg line is highly field dependent and rises with increasing iron

concentration.

[Contact: (303) 497-3650]

Recently Published

Fickett, F.R., and Capobianco, T.E. , Magnetic Field Mapping with a SQUID

Device, Proc. Review of Progress in

Quantitative NDE, Vol. 4A (Plenum

Press, New York, 1985), pp. 401-410.

[paper given at Conference, University

of California, San Diego, July 9-1 3, 1984]

Results of tests applying a S*,’ I

> (superconducting quantum interferon

device) system to measurement of H

magnetic near field of commercial < • current coils are reported. The SQUID

system offers some significant advai

tages over more conventional tf-chm jw

in that very small coils can be u the calibration of the system i tithe quantum of flux.

[Contact: (303) 497-3785]
Page 1 8 CEEE Technical Progress Bulletin - December 85

Magnetic Materials & Meas

, cont'd.

Goldfarb, R.B., Rao, K. V. , and Chen,

H.S., Differences Between Spin

Glasses and Ferroglasses: Pd-Fe-Si,

Solid State Communications, Vol. 54,

No. 9, pp. 799-801 (1985).

Near the mul ticritical point in the

magnetic phase diagram, some alloys that

appear to be simple spin glasses actually have an intermediate f erro-magne ticlike state between the high-temperature

paramagnetic and low-temperature spinglass states. The temperature dependences of the imaginary component of ac susceptibility and dc magnetization

are presented to illustrate the subtle

experimental differences between spin

glasses and these ferroglasses.

[Contact: (303) 497-3650]

Other Electrical Systems Topics

Recently Published

Sorrells, J.R., Palla, J.C., Meiselman,

8., and Oravec, B.A., Electrical and

Electronic Metrology: A Bibliography

of NBS Electrosystems Division's Publications, NBS List of Publications 94

( March 1985) .

This bibliography lists the publications

of the Electrosystems Division, Center

for Electronics and Electrical Engineering, NBS, and of its predecessor sec- tions for the period January 1968 to

March 1984. A brief description of the

Division's technical program is given in

the introduction.

[Contact: (301 ) 921-2727]

1986 CEEE CALENDAR

January 27-31 (San Jose, CA)

The Fourth International Symposium on

Semiconductor Processing. This Symposium is presented by American Society

for Testing and Materials Committee F-1 on Electronics, the National Bureau of

Standards, the Semiconductor Equipment

and Materials Institute, Stanford University Center for Integrated Systems,

and the Components, Hybrids, and Manufacturing Technology Society of the

American Institute of Electrical and

Electronics Engineers. Technical areas

to be covered include crystal growth and

material preparation technology, fabrication processes, lithography and patterning, interconnects and silicides,,

material and process characterization,

measurement and control of contaminants

introduced during fabrication and particulates, equipment technology and

automation, and manufacturing control

systems to achieve improved product

quality. Special in-depth sessions are also planned on the state of the art in

dopant profiling techniques.

[Contact: Dinesh C. Gupta (Siliconix)

(408) 988-8000]

February 17-18, 1986

IEEE VLSI Workshop on Test Structures.

The IEEE Electron Devices Society is

sponsoring a Workshop intended to bring

together the designers and users of test

chips to discuss new developments in

microelectronic test chip/test structure

research, implementation, and application. The Workshop will present papers

covering such topics as: material and

process characterization and diagnostics; device and circuit characterization; yield and reliability assessment;

test structure utilization, data analysis, and data management; and advances

in test equipment. Workshop proceedings

will be published.

[Contact: Loren W. Linholm, (301)

921-3801]

March 5-7 (Gaithersburg, MD)

Workshop on Measurement of Electrical

Quantities in Pulse Power Systems - 11.

This Workshop is intended to disseminate

information on modern measurement techniques, define the state of the art of

measurement of electrical quantities in

pulse power systems, and identify areas
CEEE Technical Progress Bulletin - December 85 Page 1

9

1986 CEEE Calendar , cont'd.

in which improvements in measurements

are required. Papers are planned for

the following three areas: (1 ) voltage,

current, power, and energy measurements,

including conventional and electrooptical techniques, beam and radiation

methods, software corrections and modeling; (2) data acquisition and processing, including signal transmission,

electro-optical links, electromagnetic

interference and noise suppression, data

recording, and diagnostics for large

systems; and (3) calibration methods for

laboratory and machine use. The Workshop proceedings will be published.

[Contact: John R. Sorrells, (301)

921-2727 or Ronald H. McKnight, (301)

921-31 21

April 22-23 (Gaithersburg, MD)

Workshop on Test Procedures for Precision Instrumentation and ATE Systems.

This Workshop is intended to provide a forum tor the exchange of information

among researchers, users, manufacturers,

testing companies, and calibration laboratories on the procedures used in testing the performance of precision instrumentation and automatic test equipment

systems. Technical topics planned include first-article and acceptance testing, bid-sample testing, maintenance and

calibration testing, developing and

writing specifications and procedures,

"minimum-use" specifications, test accuracy ratios, economic tradeoffs of testing, case histories of specific test

programs, optimum calibration strategies, and recommended practices. Ihe

Workshop proceedings will be published

by the Institute of Electrical and Electronics Engineers.

[Contact: John R. Sorrells, (301)

921-2727]

June 23-27 (Gaithersburg, MD

)

1986 CPEM (Conference on Precision Electromagnetic Measurements ) . CPEM 86 is

being sponsored by the U.S. National

Bureau of Standards, the IEEE Instrumentation and Measurement Society, and the

Union Radio Scientifique Internationale.

Ihe Conference will present papers cov- ering the theory, design, performance,

simulation, and application of electromagnetic standards, measurements, techniques, instruments, and systems. Sessions are tentatively planned to cover

the following technical areas: electromagnetic-related fundamental constants

and standards; direct current, low frequency, and radiofrequency; time, time

interval, and frequency; antennas and

fields; microwaves and millimeter waves;

infrared, visible, and ultraviolet radiation; lasers; electro-optics and fiber

optics; cryoelectronics; automated measurements; and technical calibration

services. The Conference language will

be English. [Contact: Sara Torrence,

(301) 921-2721. (For technical information, contact John R. Sorrells, (301)

921-2727 or Norman B. Belecki, (301)

921-2715. ) ]

RECENTLY ISSUED

STANDARD REFERENCE MATERIALS

The first practical superconducting

standard reference material (SRM) ha,

been released by the Electromagnetic

Technology Division to the NBS Office of

Standard Reference Materials for sale to

the public. The certified parameter of

SRM 1457, Superconducting Critical Current -- NbTi Wire, is critical current

at magnetic fields of 2,4,6, and 8 tesla

at a temperature of 4.2 K and an electric field criterion of 0.2 uV/crr.

Information is given to permit the user

to determine critical current for temperatures in the range 3.90 to 4.24 r and electric field criteria from 0.05 • 0.2 yV/cm.

SRM 1457 consists of a 2.2-m lenqth of i mul t i f i lime n ta ry , niobi urn- t i tan i m,

copper-stabilized wire, wound in a

- gle layer on a spool having a cor-- : eter of 8.7 cm. The wire is eva i ; 1

•• for 34 parameters relating to -urr<
Page 20 CEEE Technical Progress Bulletin - December 85

Recently Issued SRM , cont'd.

voltage, magnetic field, temperature,

strain, and physical specimen characteristics.

In conjunction with ASTM Standard Test

Method B714-82, D-C Critical Current of

Composite Superconductors, the new SRM

is intended to provide means for calibrating apparatus used to measure key

parameters of superconductor products

and thus should be useful to buyers and

sellers of superconductors, users of

superconducting equipment, and re- searchers in superconducting technology.

CEEE SPONSORS

National Bureau of Standards

Department of Commerce NOAA

Department of Defense

Defense Advanced Research Project

Agency; Combined Army/Navy/Air Force

Calibration Coordination Group;

Defense Nuclear Agency; National

Security Agency

U.S. Air Force

Bolling Air Force Base; Hanscom

Air Force Base; Newark Air Force

Station; Rome Air Development Center;

Space Division; Wright-Patterson Air

Force Base

U.S. Army

Aberdeen Proving Ground; Aviation

Research and Development Command;

Fort Monmouth; Harry Diamond

Laboratories; Fort Belvoir;

Redstone Arsenal; Materials and

Mechanics Research Center

U.S. Navy

Aviation Logistics Center (Patuxent

River); Naval Air Systems Command;

Naval Surface Weapons Center; Naval

Weapons Support Center (Crane);

Office of Naval Research; Naval

Research Laboratory

Department of Energy

Energy Systems Research; Fusion

Energy; Bonneville Power

Administration

Department of Justice

Law Enforcement Assistance

Administration

Charles Stark Draper Laboratory

Electronics Industries Association

Food and Drug Administration

Hughes Aircraft Company

International Copper Research

Association

International Telecommunications

Satellite Organization

Massachusetts Institute of Technology

Sandia National Laboratories

University of California Los Alamos

Scientific Laboratory
NBS-114A (rev. 2-ao) U.S. DEPT. OF COMM. 1. PUBLICATION OR 2. Performing Organ. Report No. 3. Publication Date BIBLIOGRAPHIC DATA

SHEET (See instructions)

REPORT NO.

NBSIB 85/3181-3 December 1985

4. TITLE AND SUBTITLE

Center for Electronics and Electrical Engineering Technical Progress Bulletin

Covering Center Programs, April - June 1985 with 1986 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

DEPARTMENT OF COMMERCE 8. Type of Report & Period Covered

WASHINGTON, D.C. 20234 April - June 1985

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

U.S. Department of Commerce

National Bureau of Standards

National Engineering Laboratory

Center for Electronics and Electrical Engineering

10. SUPPLEMENTARY NOTES

All technical information included in this document has been approved for

publication previously.

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

bibliography or literature survey, mention it here)

This is the eleventh 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 second quarter of calendar year 1985. Abstracts are provided by technical area

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

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by sen- cc antennas; electrical engineering; electrical power; electromagnetic interf' r< rr • ; electronics; instrumentation; laser; magnetics; microwave; optical fibers; s<-miconductors; superconductors

13. AVAILABILITY 14. NO. OF

[^Unlimited

| | For Official Distribution. Do Not Release to NTIS

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

20402.

PRINTED PAGES

IS. Price

[XlJOrder From National Technical Information Service (NTIS), Springfield, VA. 22161
U*. DEPARTMENT OF COMMERCE

National Bureau ol Standards

Gaithersburg, Md. 20899

OFFICIAL BUSINESS

Penalty for Private Use. $300

BULK RATE

POSTAGE & FEES PAID NBS

PERMIT No. G195

MR. MIKE BAUM 2036

MBS

BLDG. 101/A627

GAITHERSBURG MD 20899

KEY CONTACTS: Center Headquarters (720) Director, Mr. Judson C. French (301) 921-3357

Deputy Director, Mr. Robert I. Scace (301) 921-3357

Electrosystema Division (722) Chief, Dr. Oskars Petersons (301) 921-2328

Electromagnetic Fields Division (723) Chief, Mr. Charles K.S. Miller (303) 497-3131

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

Semiconductor Electronics Division (727) Chief, Dr. Kenneth F. Galloway (301) 921-3541

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) 921-3357