A 11 101 72fc.53k

NBSIR 78-1444-2

NAT'L INST. OF STAND & TECH

AlllDt

Semiconductor Technology

Program

Progress Briefs

W. Murray Bullis, Editor

Batfowl Bureau of Standards

APR 17 1979

Electron Devices Division

Center for Electronics and Electrical

Engineering

National Engineering Laboratory

National Bureau of Standards

Washington, D C. 20234

July 1978

Prepared for

C

00

56

8

-

The Defense Advanced Research Projects Agency

The National Bureau of Standards

The Division of Electric Energy Systems, Department of Energy

ThA Division of Solar Technology, Department of Energy

defense Nuclear Agency

Charles Stark Draper Laboratory

krmy Electronics Research and Development Command

Vir Force Avionics Laboratory

im-2
ABSTRACT — This report provides information

on the current status of NBS work in

measurement technology for semiconductor materials, process control, and devices. Results of both in-house and contract research

are covered. Highlighted activities include:

profiling of the Si-Si02 interface by Auger

electron and x-ray photoelectron spectroscopies; use of the laser scanner to detect

hairline cracks in solar cells; use of gated

diodes in evaluation of CCD imager wafers;

availability of silicon resistivity standard

reference materials; observation of unintentional channeling effects in low-fluence

random equivalent ion implantations; initiation of a comparative study of deep level

measurements; implementation of the NBSdesigned circuit for determining safeoperating-area limits of forward-biased

transistors; observation of acoustic material

signatures; availability of test pattern

NBS-4; conduct of a workshop on moisture

measurements; and comparison of carrier lifetimes as measured by the surface photovoltage

and photoconductive decay methods. In addition, brief descriptions of new and selected

on-going projects are given. The report is

not meant to be exhaustive; contacts for

obtaining further information are listed.

Compilations of recent publications and publications in press are also included.

Preface

This report covers results of work during the thirty-ninth quarter of the NBS Semiconductor

Technology Program. This Program serves to focus NBS research on improved measurement

technology for the use of the semiconductor device community in specifying materials,

equipment, anc devices in national and international commerce and in mom toring and

controllirig device fabrication and assembly. This research leads to carefully evaluated,

we 1 1 -documented test procedures and associated technology which, when applied by the

industry, are expected to contribute to higher yields, lower cost, and higher reliability of

semiconductor devices and to provide a basis for controlled improvements in fabrication

processes and device performance. By providing a common basis for the purchase specifications

of government agencies, improved measurement technology also leads to greater economy in

government procurement. Financial support of the Program is provided by a variety of Federal

agencies. The sponsor of each technical project is identified at the end of each entry in

accordance with the following code: 1. The Defense Advanced Research Projects Agency; 2. The

National Bureau of Standards; 3. The Division of Electric Energy Systems, Department of

Energy; 4. The Division of Solar Technology, Department of Energy; 5. The Defense Nuclear

Agency; 6. The C. S. Draper Laboratory; 7. The Army Electronics ROD Command; and 8. The Air

Force Avionics Laboratory.

This report is provided to disseminate results rapidly to the semiconductor community. It is

not meant to be complete; in particular, references to prior work either at NBS or elsewhere

are omitted. The Program is a continuing one; the results and conclusions reported here are subject to modification and refinement. Further information may be obtained by referring to

more formal technical publications or directly from responsible staff members, telephone:

(301) 921-listed extension. General information and a list of past publications may be

obtained from the Electron Devices Division, National Bureau of Standards, Washington, D.C.

20234, telephone: (301) 921-3786.

SEMICONDUCTOR TECHNOLOGY PROGRAM

TABLE OF CONTENTS

Profiling the Si-Si0

2 Interface . . . ^ . . 3

Detection of Cracks in Solar Cells .... 3

Gated Diodes and CCD Dark Current 4

Silicon Resistivity SRMs . 4

Unintentional Ion Channeling Effects ... 5

Deep Level Measurements 5

Transferability of SOA Test Circuit .... 5

Acoustic Material Signatures ....... 6

Availability of Test Pattern NBS-4 .... 6

Moisture Measurement Workshop 7

SPV-FCD Lifetime Comparison . . 7

New Projects 7

Work in Progress 8

Recent Publications 9

Publications in Press 10

KEY WORDS — Electronics; integrated circuits;

measurement technology; microelectronics;

semiconductor devices; semiconductor materials; semiconductor process control; silicon.

2
NBS NBS Semiconductor Technology Program

Progress Briefs

Profiling the Si-Si0 2 Interface

Contract efforts are currently underway to

develop and refine the application of

X-ray Photoelectron Spectroscopy (XPS) and

Auger Electron Spectroscopy (AES) for the

examination and control of electron device

structures. Papers describing the application of these measurement tools to determine the chemical structure of the interface between silicon and thermally grown

silicon dioxide were recently presented at

the International Topical Conference on

the Physics of SIO2 and Its Interfaces

(York town Heights, NY, 22-24 March 1978).

In the XPS work (performed at JPL), depth

profiling was accomplished using a newly

developed wet-chemical etching technique

which minimizes the perturbation of the

remaining oxide due to oxide-solvent reaction. The data from this work indicate

that the stoichiometry of Si(>2 as determined by XPS is essentially uniform except

for a transitional zone within '\»0.5 nm of

the interface. The data also give evidence

for intermediate oxidation states near the

interface.

In the AES work (performed at Stanford

University >, depth profiling was accomplished using a 1-keV argon beam to remove

material by sputtering. The data are

deconvolved to account for ion beam

knock-on and electron escape depth effects

in order to improve the depth resolution.

The results indicate that there is a

transition region between essentially pure

Model of the Si-Si02 interface as derived

from sputter Auger studies.

SiC>2 and essentially pure Si no greater

than 0.8 nm wide which undulates with a period of less than 100 ym and a peak-topeak amplitude of about 2 nm. This picture

of the interface, illustrated in the

accompanying figure, is consistent both

with the one emerging from the XPS work

and with the results of published transmission electron microscope studies.

[Sponsor: 1] (K. F. Galloway,* x3625)

Detection of Cracks in Solar Cells

The presence of hairline cracks in a photovoltaic solar cell can significantly

degrade both the power output and the

reliability of the cell. A technique based

on the laser scanner has been developed to

detect these tiny cracks, which frequently

cannot be observed visually. In this

technique the cell is forward biased

during laser scanning either electrically

with a current source or optically by

shining light on the cell, or by a combination of both methods. The crack is

revealed by a change in the slope of the

photoresponse signal as the laser beam

crosses the crack. In some cases, the

magnitude of the photoresponse is different on the two sides of the crack so that

there is also an abrupt change in magnitude of the signal as the beam crosses the

crack. The photoresponse is displayed on a TV screen to permit visual observation of

the cracked region. This technique can

also be used to observe and identify

regions of the grid metallization of a solar cell which are not in good contact

with the cell emitter region (that portion

of the cell between the p-n junction and

the illuminated surface). Analysis of a distributed resistance representation of

the solar cell predicts that the photoresponse to a scanning light beam should

rise to a common maximum at the edges of

the emitter metallization provided that

(1) the metallization edge in question is

3

*NBS Contact.
electrically continuous to the cell leadwire and (2) a good ohmic contact exists

between the metallization and the emitter.

However, in regions of ineffectual contacting the analysis predicts that the

signal should not rise. Observations on

cells with known metallization faults

confirmed the predictions of the analysis.

These results were reported to the 13 th

IEEE Photovoltaic Specialists Conference

in June. [Sponsor: 4](D. E. Sawyer, x3621)

Gated Diodes and CCD Dark Current

Preliminary measurements on a gated diode

test structure suggest that this test

structure will be useful in revealing

unexpected and undesirable effects which

impact directly on the performance of CCD

imagers. With the addition of an on-chip

MOSFET amplifier, which serves as an

electrometer, the combined test structure

becomes compatible with high-speed dc data

acquisition techniques, and the diode

dimensions can be reduced to sizes typical

of integrated circuit elements. Initial

measurements were made on 'the gated diode

test structures on test pattern NBS-12,

shown in the figure. These diodes were

found to exhibit excess leakage currents

Computer-generated composite drawing of

gated diode on bi-MOS test pattern NBS-12.

Contact pads: G, gate; B , p+ base diffusion (source); C) n-collector region

(body)

at high gate potentials. Due to a geometrical configuration which maximizes the

perimeter of the diode and its gate,

surface generation occurring at the edges

of the depletion layer, where it intersects the Si-Si02 interface, is enhanced.

Zener emission and impact ionization may

also contribute at edges or corners. Such

excess leakage currents were initially

unwelcome. However, it appears that their

presence has serendipidously uncovered a

likely mechanism for unexpected surface

leakage in some CCD designs in which such

leakage is likely to be manifested as an

undesirable component of dark current in

the output gates . Experiments are underway

to further understand the nature of this

surface leakage and how it depends on the

design of the gated diode structure,

including such parameters as the length of

the gate perimeter, the overlap of the

gate and the junction and channel stop

diffusions, and the properties of the gate

oxide. [Sponsor: 6] (G. P. Carver, x3541)

Silicon Resistivity SRMs

Twenty additional sets of the silicon

resistivity standard designated as SRM

1520: Boron-Doped Silicon Slices for Resistivity Measurement have been certified

and are now ready for release. This

standard reference material consists of

two boron-doped silicon single-crystal

slices, one with a nominal resistivity of

0.1 fi*cm, the other with a nominal resistivity of 10 fi*cm. The slices have a [111]

crystallographic orientation and are approximately 42 mm in' diameter and 1 mm

thick. They are intended for use with

four-probe resistivity testers. In addition, twenty more sets of such standards,

identical to the above, except that the

thickness has been reduced to less than

0.76 mm for use with contactless resistivity gauges in addition to the standard

four-probe testers, have also been certified. These sets will be available under

the designation, SRM 1521: Boron-Doped

Silicon Slices for Resistivity Measurement. The SRM sets may be ordered from the

Office of Standard Reference Materials,

National Bureau of Standards, Washington,

4
DC 20234. The cost of each set is $176.

[Sponsor: 2] (J. R. Ehrstein, x3625)

Unintentional Ion Channeling Effects

Unintentional channeling during ion implantation can lead to the formation of

undesirable deeply penetrating tails in

the depth distributions of implanted dopants, especially during low fluence implantations. The magnitude of these dopant

tails depends on the angle the ion beam

makes with the substrate crystal axes. A

joint effort was undertaken with Hughes

Research Laboratories to analyze the variation of dopant profiles with the angle of

beam incidence. Dopant profiles were determined by differential capacitancevoltage measurements at 1-MHz. The results

clearly indicate that the beam must be

oriented at an angle with the nearest

low-index crystal direction which is at

least twice the classical critical angle

for channeling in order to minimize

unintentional channeling. The critical

angles, which were calculated by a simple

but accurate procedure, were found to vary

from 2 to 7 deg from common industrial

implants. Therefore, minimizing the extent

of unintentional channeling during implantation requires tilt angles of 4 to 14

deg. These angles can easily exceed the 7-

to 10-deg tilt angles commonly used in

implantation. These results are being

written up as an NBS special publication.

[Sponsors: 1,2] (D. R. Myers,* x3625)

Deep Level Measurements

A comparative study is being initiated so

that interested laboratories can assess

their ability to accurately measure deep

level impurities. In this study, a pair of

gold-doped silicon gated diodes is available for measurement of defect energy

levels and associated densities and emission rates by each interested laboratory.

When sufficient results have been obtained, the measured values and the

methods used by the participating laboratories will be compiled. However, the

names of the participating laboratories

will not be associated with their data in

this compilation. It is hoped that this

type of inter laboratory comparison will

raise the general level of competence in

the field of deep level measurements to a point that they will become more effectively and widely used by the semiconductor industry. Laboratories interested in

participating in this comparative study

should contact the Electron Devices Division, A353 Technology, NBS, Washington, DC

20234. [Sponsors: 1,2,3]

(D. R. Myers,* x3625, W. E.

Phillips, x3625, and R. Y. Koyama, x3625)

Transferability of SOA Test Circuit

Safe-operating-area limits of forwardbiased bipolar transistors which exclude

operation in the hot-spot, or currentconstricted, mode can be determined with

the circuit shown schematically in the

figure. The method involves the measurement of the time derivative of the

emitter-base voltage, which shows a welldefined peak at the onset of hot-spot

formation. The method and associated circuit were described at the 1977 IEEE Power

Electronics Specialists Conference and the

1977 Annual Meeting of the IEEE Industrial

Block diagram of circuit used to generate

SOA limit based upon the limit of thermal

instability (switches in position A).

With switches in position B circuit can be

used to measure thermal resistance by the

*NBS-NRC Postdoctoral Research Associate. standard method . 5
Applications Society. To aid in implementation of this method, NBS can provide

detailed diagrams of the circuit. In

addition, several different devices in

TO-3 packages are available for circulation to groups who have built the NBSdeve loped test circuit so that they may

evaluate their circuits. If enough organizations take advantage of this opportunity, the data will be summarized to

establish an estimate of the inter laboratory reproducibility of the method. Groups

desiring information on the method or to

obtain the test devices should contact the

Electron Devices Division, A353 Technology, NBS, Washington, DC 20234. [Sponsor:

2] (D. L. Blackburn, x3621)

Acoustic Material Signatures

Scanning acoustic micrographs of integrated circuits not only show a large

range of contrast between adjacent details

in the field of view, but the contrast can

be varied or even reversed if the distance

from the lens to the specimen is changed.

To understand why this occurs, the acoustic reflectance of a variety of materials

as a function of lens-to-specimen spacing

Acoustic material signature (relative

reflected power as a function of lens-tospecimen spacing, z) for <100> surface of

silicon .

has been measured at Hughes Research

Laboratories. Each material so far examined has a unique reflectance characteristic, frequently with a number of strong

minima whose depth and spacing differ for

each. These minima are believed to arise

because surface waves are excited in the

material, and at specific lens-to-specimen

distances destructive interference occurs

between the normal acoustic return from

the specimen and energy re-radiated from

the surface wave. Since the velocity of

propagation of surface waves is characteristic of the material, and also depends

on the direction of propagation in the

material, the reflected energy versus lens

spacing response is material dependent. In

specimens such as integrated circuits

where several materials may be present,

the contrast changes can be understood as a superposition of responses of the

different materials. [Sponsor: 1]

(R. I. Scace,* x3625)

Availability of Test Pattern NBS-4

Documentation for microelectronic test

pattern NBS-4 is now available as NBS

Special Publication 400-32 in the Semiconductor Measurement Technology series. The

NES-4 pattern contains 38 test structures

such as planar four-probe resistors, sheet

resistors, MOS capacitors, p-n junctions,

bipolar and MOS transistors, Hall effect

device, and etch control and resolution

structures. The overall pattern is a square 200 mil (5.08 mm) on a side and is

divided into four quadrants which are

separated by scribe lines. This pattern

was designed principally for use in

measuring resistivity and dopant density

of n- and p-type silicon slices with resistivity from 10 14 to 10 2y fi*cm at room

temperature. It has been used both at

NBS and at the University of Florida in

studies to relate resistivity, carrier

density, and dopant density in silicon.

The structures contained on the pattern

are, like those on earlier test patterns

NBS-2 and NBS-3, also of value for

measuring parameters in setting up and

controlling processing of semiconductor

6

*NBS Contact.
devices. The earlier mask sets have been

released to over 50 government, industrial, or academic laboratories. Requests for

releasing the mask set for test pattern

NBS-4 from a commercial mask-making company may be addressed to M. G. Buehler.

The cost of a mask set is about $200.

[Sponsors: 1,2] (M. G. Buehler,- x3541 and

W. R. Thurber, x3625)

Moisture Measurement Workshop

The f'fth in a series of ARPA/NBS workshops concerned with measurement problems

in integrated circuit • processing and assembly was held at NBS-Gai thersburg on

March 22 and 23. The workshop examined

present problems with the measurement of

moisture in hermetic semiconductor devices, a dangerous and pervasive contaminant. The urgency of these problems is

compounded by the recent adoption of

moisture measurement test methods in MILSTD-883. The workshop featured 20 formal

talks and several group and panel discussions. The 150 attendees represented a

broad spectrum of the semiconductor and

related communities concerned with moisture measurement . The measurement approaches addressed in detail were those

using mass spectrometers and moisture

sensors (aluminum oxide and surface conductivity types). The workshop concluded:

1) for all of the methods used to make

measurements in device packages, one can

only talk about precision — not accuracy;

2) none of the measurement techniques now

available is ready for use by inexperienced personnel; and 3) the precision or

repeatability of moisture measurement will

not really be satisfactory until much more

is done to characterize mass spectrometers

and moisture sensors in terms of alZ the

variables, conditions, and applications

that can affect the measurement. During

the workshop, about 60 workshop attendees

signed a formal request to NBS for

assistance in moisture measurements, especially with respect to traceable standards. In addition, there were numerous

expressions of interest in subsequent

workshops on moisture measurement. [Sponsor: 1] (H. A. Schafft, x3625)

SPV-PCD Lifetime Comparison

An investigation showed that bulk crystal

damage near the semiconductor surface can

lead to the often observed discrepancy

between the bulk carrier lifetimes measured by the surface photovoltage (SPV)

and photoconductive decay (PCD) methods.

Both PCD and SPV measurements were made on

high resistivity (^lOO fi’cm) , high lifetime (0. 1-1.0 ms) silicon slices. The

lifetimes as measured by the PCD method on

lapped and chem-mechanically polished

specimens were consistently one to two

orders of magnitude longer than those

measured by the SPV method. Also, the SPV

plot (intensity, I, versus reciprocal absorption coefficient, a *) was not linear

as required by theory but was concave

downward for a” 1 greater than about 100

ym. All of the assumptions of the SPV

theory concerning specimen thickness with

respect to a

-1 and diffusion length were

met. A theoretical analysis showed that

the I versus a” 1 data could be qualitatively explained by a two-lifetime model:

a short lifetime near the surface and a long lifetime deeper within the bulk. It

was found that after removal of the

short-lifetime surface region by etching

in a solution of 10 parts hydrofluoric

acid, 6 parts of nitric acid, and 4 parts

hydrochloric acid the SPV data showed the

expected linear relationship, and the

value of lifetime measured by the SPV

method approached that measured by the PCD

method. [Sponsor: 2]

(D. L. Blackburn, x3621)

New Projects . . .

Photoresist Adhesion — A study of

photoresist-substrate adhesion mechanisms

has been initiated. Experiments are being

conducted to determine the effect of a

silica surface on the chemistry of the

photoactive component of negative resist.

In addition, model polymers are being

synthesized. These will be used to determine the relationship between polymer

adsorption and film adherence. [Sponsor:

2] (J. A. Hinkley,* x3621)

7

NBS-NRC Postdoctoral Research Associate.
Hydrogen Contamination in Thermal Oxides —

Work has been initiated on analyzing the

mechanisms through which hydrogen and

hydroxyl impurities become incorporated

into thin, thermally grown silicon dioxide

films prepared in "dry" oxidation atmospheres enclosed in resistance-heated

fused silica or silicon furnace tubes.

Calculations of the hydrogen content in

silicon dioxide films suitable for producing radiation-hardened MOS devices will be

made in comparison with the available

experimental results. Previous work indicates that environmental conditions such

as the substrate, the purity of the

oxidation atmosphere, and the furnace tube

quality directly affect film composition

and properties. The amount of water

contamination in a typically nominally

"dry" oxidation atmosphere, using electronic grade oxygen with no special

preoxidation treatment, enclosed in a

fused silicon tube at 1000°C is about 20

ppm. Consequently, the hydrogen and hydroxyl impurities in thin silicon dioxide

films can probably be explained in terms

of the water introduced into the oxidation

atmosphere with the "dry" oxygen. This and

other possible mechanisms will be examined

quantitatively. [Sponsor: 5]

(S. Mayo, x3625)

Standard Reference Materials — A third

standard reference material for four-probe

resistivity measurements is being produced

in order to provide the high-power semiconductor device industry with silicon

slices of calibrated resistivity. The set

will consist of three slices of neutron

transmutation doped silicon with nominal

room temperature resistivities of 25, 75,

and 180 cm. The slices are 51 mm in

diameter and 0.64 mm thick.

In addition, a study has been undertaken

to determine the effect of storage on the

stability of the calibration value of

thermally grown oxide on silicon to serve

as standard reference materials for measurement of oxide film thickness. Silicon

slices were thermally oxidized to form a silicon dioxide layer about 50 nm thick.

Groups of four slices each are being

stored under one of seven test conditions.

The thickness of each oxide film is being

measured ellipsometrically on a periodic

basis to establish the short-term (a-2

weeks) and long-term (^6 months) stability

of the thickness. A similar set of tests

is also to be run on 100-nm thick oxides.

[Sponsor: 2] (J. R. Ehrstein, x3625)

Hall Measurements in Two-Layer Structures

— In many cases it is desired to characterize by means of Hall effect and

resistivity measurements two-layer structures in which there is a p-n junction at

the interface. In general, the junction

must be considered to have a finite,

nonzero impedance which couples the two

layers together and thus interferes with

conventional Hall measurements. To meet

the need for nondestructive ly characterizing such structures, a modification of the

conventional Hall technique is being studied. In this modification which requires

ohmic contacts to both layers, Hall

measurements are made simultaneously on

both layers, and the interface impedance

is measured and taken into account. The

equations necessary for analyzing the

results of the measurements have been

developed, and experimental tests of the

method are being initiated. [Sponsor: 7]

(R. D. Larrabee, x3625)

CMOS/SOS Test Pattern — Work has begun on

designing a test pattern (NBS-16) to

develop process assessment methods which

can be used by an independent source to

evaluate the electrical performance, radiation tolerance, and yield potential of

LSI circuits fabricated with a radiationhardened, silicon-gate CMOS/SOS process.

The project is being carried out in

collaboration with the Jet Propulsion

Laboratories and RCA. NBS and JPL are

designing the test pattern. After fabrication of the pattern by RCA under an AFAL

contract, NBS and JPL will measure and

evaluate the pattern. [Sponsor: 8]

(L. W. Linholm, x3541)

Work in Progress . . .

Hall effect and resistivity measurements

on silicon specimens with phosphorus dopant densities in the range 1019 to 10

cm 3, being made as part of the reevalua8
tion of the resistivity-dopant density

relations in silicon now nearing completion, suggest that for a given dopant

density the resistivity is 5 to 10 percent

lower than that given by the Irvin curve.

[Sponsor: 1] (W. R. Thurber , x3625

)

The feasibility of using plasma etching to

form mesa diode structures for deep-level

measurements on partially or fully fabricated thyristor wafers was demonstrated.

With an available etch rate of about 40

ym/h, mesa structures were routinely fabricated with a moat-etch as deep as 80 to

90 ym, which is compatible with junction

depths in commercial thyristor structures.

Studies have been initiated to determine

the optimum technique for making contact

to che high resistivity rz-type region and

for optimizing the size of the mesa diodes

to compensate for lateral etching during

mesa formation. [Sponsor: 3] (R. Y.

Koyama, x3625, and J. Krawczyk, x3541)

Calibration of ten artifacts to be used in

the interlaboratory evaluation of the

line-width measurement procedure was completed. Following revision of the test

instructions to incorporate calibration

procedures for direct-reading TV-type microscope measuring instruments, the artifacts were distributed to the ten participants. [Sponsors: 1,2](J. M. Jerke, x2185)

Various limitations of the dc MOSFET

method for measuring dopant profiles were

analyzed. It was found that the principal

limitations were those associated with the

fact that, as in high-frequency

capacitance-voltage methods, the dopant

density is measured within the depletion

layer so that profiles can be measured

only where the material can be depleted of

holes and electrons. Thus, the region from

about three Debye lengths from the oxidesilicon interface to a depth limited by

avalanche breakdown in the silicon can be

profiled by these methods. [Sponsors: 1,5]

(M. G. Buehler, x3541)

The ultraviolet reflectance technique,

developed at RCA Laboratories to evaluate

silicon films epitaxially grown on sapphire, has also been shown to be sensitive

* NBS Contact.

+ Reports of Contract Research.

to surface damage on polished silicon

wafers cut from single-crystal boules.

[Sponsor: 1] (K. F. Galloway,* x3625)

Recent Publications . . .

Buehler, M. G., Microelectronic Test Patterns for Use in Procuring Custom and

Highly Reproducible Integrated Circuits,

Proc. Symposium on Utilization of LSICs

in Military Systems , Arlington, Virginia,

August 9-11, 1977, pp. Ill 102-III 117.

Bullis, W. M. , The NBS Semiconductor

Technology Program, Proo. Symposium on

Utilization of LSICs in Military Systems , Arlington, Virginia, August 9-11, 1977,

pp. Ill 87-III 101.

Sawyer, D. E., Solar Cell Measurement

Technique Development and Other Services

,

Proo . Photovoltaios Program Semi-Annual

Review, Advanced Materials R&D Branch , Golden , Colorado , October 4--6, 1977, pp.

708-713.

Swyt , D . A .

,

Rosberry

,

F. W. , and

Nyyssonen, D., Calibration of Optical

Microscopes for Photomask Linewidth Measurements , Proo. Microelectronics Seminar — Interface ' 77 , Monterey, California,

October 5-7, 1977, pp. 131-144.

Swyt, D. A., An NBS Physical Standard for

the Calibration of Photomask Linewidth

Measuring Systems, SPIE, Vol. 129, Effective Utilization of Optics in Quality

Assurance , 98-105 (1977).

Zanzucchi, P. J., Duffy, M. T., and Alig,

R. C., Optical Reflectance Method for

Determining Surface Quality of Sapphire,

J. Electrochem. Soc. 125 , 299-305

(February 1978).

tHelms , C. R. , Spicer, W. E., and Johnson,

N. M. , New Studies of the Si-Si02 Interface Using Auger Sputter Profiling, Solid

State Comm. 25_, 673-676 (March 1978).

Koyama, R. Y., Blackburn, D. L., and

Oettinger, F. F. , Measurement Techniques

for High Power Semiconductor Materials

and Devices, Proc.: Light-Fired Thyristor Workshop , EPRI Report WS-77-049,

unpaged (March 1978).

Buehler, M. G. , and Thurber, W. R. , An

Experimental Study of Various Cross Sheet

Resistor Test Structures, J. Electrochem

.

Soc. 125, 645-650 (April 1978).
Buehler, M. G. , Grant, S. D., and Thurber,

W. R. , Bridge and van der Pauw Sheet

Resistors for Characterizing the Line

Width of Conducting Layers, J. Electroahem. Soc. 125 , 650-654 (April 1978).

*Christou, A., Semiconductor Measurement

Technology : Automated Scanning LowEnergy Electron Probe (ASLEEP) for Semiconductor Wafer Diagnostics, NBS Spec.

PubL 400-30 (April 1978).

Galloway, K. F. , and Mayo, S., Radiation

Dose at the Silicon-Sapphire Interface

Due to Electron-Beam Metallization, J.

Appl. Phys. 49_, 2586-2588 (April 1978).

Novotny, D. B., and Ciarlo, D. R. , Semiconductor Measurement Technology: Automated Photomask Inspection, NBS Spec.

Publ. 400-46 (April 1978).

Thurber, W. R. , and Carpenter, B. S.,

Boron Determination in Silicon by the

Nuclear Track Technique , J, Electrochem.

Soc . 125 , 654-657 (April 1978).

Thurber, W. R. , and Buehler, M. G.,

Semiconductor Measurement Technology : Microelectronic Test Pattern NBS-4, NBS

Spec. Publ. 400-32 (April 1978).

Publications in Press . . .

*Atalar, A., An Angular Spectrum Approach

to Contrast in Reflection Acoustic Microscopy, J. Appl . Phys

.

Blackburn, D. L., Photovoltaic Technique

for Measuring Resistivity Variations of

High Resistivity Silicon Slices, NBS J

.

Res

.

Blackburn, D. L., and Larrabee, R. D.,

Automated Photovoltaic Technique for Nondestructively Measuring Resistivity Variations of High-Resistivity Silicon Wafers , Proc. Topical Conf, on Characterization Techniques for Semiconductor

Materials and Devices , Seattle, Washington, May 21-26, 1978.

Buehler, M. G., Microelectronic Test Patterns for Use in Procuring LSICs, Proc

.

Industry/Joint Services Automatic Test

Conf. and Workshop , San Diego , California, April 4-6, 1978.

Buehler, M. G., Limitations and Applications of the D-C MOSFET Profile Method,

Proc. Topical Conf. on Characterization

Techniques for Semiconductor Materials

and Devices , Seattle, Washington, May 21-

26, 1978.

Bullis , W. M, , Government Programs on

Advanced Technology and Manufacturing

Techniques: Comments on USA, Japan, and

Europe, NBSIR 78-1482.

Bullis, W. M. , and Mayo-Wells, J. F., Eds,

Semiconductor Measurement Technology,

Progress Report, July 1 to September 30,

1976, NBS Spec. Publ. 400-36.

Galloway , K . F . , and Mayo , S . , On The

Compatibility of X-Ray Lithography and

SOS Device Fabrication, IEEE Trans. Electron Devices . *Grunthaner, F. J., and Maserjian, J.,

Chemical Structure of the Transition

Region of the Si02/Si Interface, Proc.

Intemat. Topical Conf. on Physics of

SiOi and Its Interfaces , Yorktown

Heights, New York, March 22-24, 1978.

Harman, G. G., and Cannon, C. A., The

Microelectronic Wire Bond Pull Test - How

to Use It, How to Abuse It, Proc. 28th

Electronic Components Conf. , Anaheim,

California, April 24-26, 1978.

*Helms, C. R. , Johnson, N. M., Schwarz, S.

A., and Spicer, W. E., Auger Sputter Profiling Studies of the Si-Si02 Interface

,

Proc . Intemat. Topical Conf. on Physics

of SiOi and Its Interfaces , Yorktown

Heights, New York, March 22-24, 1978.

*Helms, C. R. , Johnson, N. M., Schwarz, S.

A., and Spicer, W. E., Auger Sputter

Profiling Studies of the Si-Si02 Interface, Proc. Topical Conf. on Characterization Techniques for Semiconductor Materials and Devices , Seattle, Washington,

May 21-26, 1978.

*Jamba, D. M. , Secondary Particle Collection in Ion Implantation Dose Measurement, Rev. Sci. Instrum.

Koyama, R. Y., Detection of Deep Levels in

High Power Semiconductor Materials and

Devices , NBS J. Res

.

Koyama, R. Y., Phillips, W. E., Myers, D.

R. , Liu, Y. M. , and Dietrich, H. B., The

Energy Levels and the Defect Signature of

Sulfur-Implanted Silicon by ITCAP and TSC

Measurements, Solid-State Electronics.

Koyama, R. Y. , Wafer Mapping of Electrically Active Devices, Proc. Topical Conf.

on Characterization Techniques for Semi-

( Continued on Back Cover) * Reports of Contract Research. 10
MBS-114A (Rev. 7-73)

U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET

1. PUBLICATION OR REPORT NO.

NBSIR 78-1444-2

2. Gov’t Accession

No.

3. Recipient’s Accession No.

4. TITLE AND SUBTITLE

Semiconductor Technology Program — Progress Briefs

5. Publication Date July 1978

6. Performing Organization Code

7- V’.TW

,

.R(

iuiiis

8. Performing Organ. Report No.

9. PERFORMING ORGANIZATION NAME AND ADDRESS

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

and various contractor facilities (as noted)

10. Projeci/Task/Work Uoit No.

11. Contract/Grant No.

See item 15

12. Sponsoring Organization Name and Complete Address (Street, City. State, ZIP)

HBS, Washington, DC 20234; APPA, Arlington, VA 22209; DNA, Washington,

DC 20305; Dept, of Energy, Washington, DC 20545; C. S. Draper Laboratory, Cambridge, MA 02139; AFAL, Wright-Patterson AFB, OH 45433; Army

Electronics R6D Command, Ft. Belvoir, VA 22060.

13. Type of Report 8c Period

Covered Interim

January - March 1978

14. Sponsoring Agency Code

15. SUPPLEMENTARY NOTES

ARPA Order 2397; Program Code 8Y10; DNA IACR0 78-807; Dept, of Energy, Interagency Agreement EX-77-A01-

6010, Task Orders A021-EES and A054-SE; C. S. Draper Laboratory, P. 0. DL-H-139485 (Navy contract N 00030-78-C-0100) ; AFAL, MIPR FY117578N2026; Army Electronics, HERADC0M, P. 0. 28052.

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

bibliography or literature survey, mention it here.)

This report provides information on the current status of NBS work in measurement technology for semiconductor materials, process control, and devices. Results of both inhouse and contract research are covered. Highlighted activities include: profiling of

the Si-Si02 interface by Auger electron and x-ray photoelectron spectroscopies; use of

the laser scanner to detect hairline cracks in solar cells; use of gated diodes in

evaluation of CCD imager wafers; availability of silicon resistivity standard reference

materials; observation of unintentional channeling effects in low-fluence random equivalent ion implantations; initiation of a comparative study of deep level measurements;

implementation of the NBS-designed circuit for determining safe-operating -area limits

of forward-biased transistors; observation of acoustic material signatures; availability

of test pattern NBS-4; conduct of a workshop on moisture measurements; and comparison

of carrier lifetimes as measured by the surface photcvoltage and photoconduct ive decay

methods. In addition, brief descript ions of new and selected on-going projects are

given. The report Is not meant to be exhaustive; contacts for obtaining further information are listed. Compilations of recent publications and publications in press are . also included . r

i

17. KEY WORDS (six to twelve entries; alpt.abetical order; capitalize only the first letter of the first key word unless a proper name; separated by semicolons)

Electronics; integrated circuits; measurement technology; microelectronics; semiconductor devices; semiconductor materials; semiconductor process control; silicon.

18. AVAILABILITY fX. Unlimited

|

I For Official Distribution. Do Not Release to NTIS

Order From Sup. of Doc., U.S. Government Printing Office Washington, D.C. 20402, SD Cat. No. CU

E °fder F rom National Technical Information Service (NTIS)

Springfield, Virginia 22151

19. SECURITY CLASS

(THIS REPORT)

21. NO. OF PAGES

12

UNCLASSIFIED

20. SECURITY CLASS 22. Price

(THIS PAGE)

$4.00

UNCLASSIFIED

USCOMM.DC 2 0042- P 7

4
(Continued from Page 10)

conductor Materials and Devices , Seattle,

Washington, May 21-26, 1978.

Koyama, R. Y., Techniques for Characterizing Defects in Starting Silicon Wafers

Using TSM, Proc. Topical Conf. on Characterization Techniques for Semiconductor

Materials and Devices , Seattle , Washington, May 21-26, 1978.

Larrabee, R. D., Interpretation of Hall

Measurements, Proc. Topical Conf. on

Characterization Techniques for Semiconductor Materials and Devices , Seattle

,

Washington, May 21-26, 1978.

Larrabee, R. D., "X” Levels in IndiumDoped Silicon, Proc. IRIS Specialty Group

Meeting , Annapolis, Maryland, June 13-15,

1978.

*Li, S. S., The Dopant Density and Temperature Dependence of Hole Mobility and

Resistivity in Boron-Doped Silicon,

Solid-State Electronics.

Myers, D. R., and Phillips, W. E., Existence of an Isotope Shift for the Sulfur

Deep Level in Silicon, Appl. Phys.

Letters.

Novotny, D. B., and Ciarlo, D. R. , Automated Photomask Inspection, Solid State

Technology

.

Nyyssonen, D., Optical Linewidth Measurements on Wafers, SPIE, Vol. 1359 Developments in Semiconductor Micro

lithography III.

* Reports of Contract Research.

Oettinger, F. F. , Ed, Measurement Techniques for High Power Semiconductor Materials and Devices, NBSIR 78-1474.

Sawyer, D. E. , A Technique for Using an

Optical Scanner to Reveal Solar Cell

Defects, Proc. 13th IEEE Photovoltaic

Specialists Conference.

*Schwarz, S. A., Helms, C. R. , and Spicer,

W. E., Auger Sputter Profiling Studies of

Dopant Pileup at the Si-Si02 Interface,

J. Vac. Sci. Technol.

*Strausser, Y. E., Scheibner, E. J., and

Johannessen, J. S., Observations of AI2O3

and Free Si in the Interface Between A1

Filins and Si0 2 , Thin Solid Films.

*Strausser, Y. E., and Majumder, K. S., The

Chemical Structure of the Al/Si02 Interface, J. Vac. Sci. Tech.

Thurber , W. R. , Mattis, R. L. , and Liu, Y.

M., Resistivity-Dopant Density Relationship for Silicon, Proc. Topical Conf. on

Characterization Techniques for Semiconductor Materials and Devices , Seattle,

Washington, May 21-26, 1978.

*Weglein, R. D., and Wilson, R. G., An

Acoustic Gray Scale for Scanning Acoustic

Microscopy and Diagnostic Ultrasound,

Ultrasound Imaging.

*Wilson, R. G. , and Weglein, R. D., Acoustic Material Signatures Using the Reflection Acoustic Microscope, Proc. 1st

Internet. Symp. Ultrasonics Mat Is. Characterization, Washington, D.C., June 8-

10, 1978.

Ufy.rn'X.t • • ,

; f

! v- • ^ < U.S. DEPARTMENT OF COMMERCE. Juanita M. Kraps, Secretary

Dr. Sidney Herman. Under Secretary

Jordan J. Baruch, Assistsnt Sscrstsry for Science end Technology

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director