IPC-D-279 EN.pdf - 第44页

Cooling T echniques for Electronic Equipment, 2nd Edition, Dave S. Steinberg; W iley Interscience, 1991, ISBN 0-471- 52451-4. Chapter 8 addresses combined vibration and ther - mal stresses. Shock and V ibration, 3rd Edit…

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Dave S. Steinberg; Wiley Interscience, 1991, ISBN 0-471-
52451-4. Chapter 8 addresses combined vibration and ther-
mal stresses.
Technology Assessment of Laminates, IPC-TA-720, IPC
Materials for High Density Electronic Packaging and Inter-
connection, National Materials Advisory Board, Commis-
sion on Engineering and Technical Systems, National
Research Council, NMAB-449, April 10, 1990
See also IPC documents on various design aspects.
9.13 Substrate Fabrication Information
Printed Circuits Handbook, 4th Edition, Coombs, C. F., Jr.;
Mc-Graw Hill, Inc.; 1996; ISBN 0-07-012754-9
See also IPC publications on High Speed, Rigid, Flexible,
Single-Sided and Double-Sided Substrates, Solder Mask,
Conformal Coat
9.14 Component Derating, Applications, Qualification
Surface Mount Technology (As It Applies to Capacitors,
Resistors and Magnetics), CARTS; 1988 Seminar Notes,
particularly Section 7.
Components Engineering and Reliability Handbook;
CARTS/Component Technology Institute, Inc.; 1991.
Component Technology and Reliability Revision 2, Fred
Watts; Sav-Soft Products; 1988; See also his Reliability
Prediction Methodologies; 1988
Component Derating, Applications, Qualification Ionizing
Radiation Effects in MOS Devices and Circuits, T. P. Ma
and P. V. Dressendorfer, John Wiley and Sons, 1989, ISBN
0 471 84893-X
See also IPC publications on Connectors, Plastic Surface
Mount Components
See also EIA publications on various Passives
See also EIA-J publications on SQFP and TSOP
9.15 Testability, Manufacturability
The Board Designers Guide to Testable Logic Circuits,
Colin Maunder, Addison Wesley, 1991, ISBN 0-201-
56513-7
Design for Manufacturability, David M. Anderson, CIM
Press, 1990, ISBN 1-878072-11-0
Design for Manufacture, John Corbett, Mike Dooner, John
Meleka, and Christopher Pym, Addison-Wesley, 1992,
ISBN 0-201-41694-8.
The Design of Testable Logic Circuits, Bennetts, R. G.,
Van Nostrand Reinhold, 1984, ISBN 0-201-14403-4 (Out
of Print, December, 1991)
Design to Test: A Definitive Guide for Electronic Design,
Manufacture and Service, 2nd Edition, Jon Turino, Van
Nostrand Reinhold, 1990, ISBN 0-442-00170-3
The Effect of Product Design on Product Quality and Prod-
uct Cost , Douglas Daetz, Quality Progress, June 1987, pp
63-67.
Digital Systems Testing and Testable Design, Abramovici,
M., Breuer, M.A., Friedman, A. D., Computer Science
Press, 1990, ISBN 0-7167-8179-4
Engineering Design: Reliability, Maintainability and Test-
ability, James V. Jones, TAB Professional and Reference
Books, 1988, ISBN 0-8306-3151-8
IEEE Standard Testability Bus Definition
1149.1-1990, IEEE Standard Test-Access Port and
Boundary-Scan Architecture
P1149.1a - defining the extensions/corrections to 1149.1
P1149.2, Extended Digital Serial Subset
P1149.3, Real-Time Parallel Digital Interface
P1149.4, Analog Testability Bus
P1149.5, Test and Maintenance Backplane Bus
Logic Testing and Design-For-Testability, Fujiwara, H.,
MIT Press, 1985, ISBN 0-262-06096-5
Managing Concurrent Engineering: Buying Time to Mar-
ket, Jon Turino, Van Nostrand Reinhold, 1990, ISBN
0-442-00170-3
Reliability and Maintainability Software Tools, December
1991, Robert J. Borgovini, RMST-91, Reliability Analysis
Center, Rome, NY
SMT Design for Testability, James C. Blankenhorn, SMT-
Plus
Structured Logic Testing, Eichelberger, E. B., Lindbloom,
E., Waicukauski, J.D., Williams, T.W., Prentice Hall, 1991,
ISBN 0-13-853680-5
Survey of Reliability, Maintainability, Supportability and
Testability Software Tools, Joseph A. Caroli, RL TR 91-87,
April 1991, AD-A236 148, NTIS
Testability Design and Assessment Tools, December 1991,
Richard Unkle, CRTA-TEST, Reliability Analysis Center,
Rome Laboratory, P.O. Box 4700, Rome, NY 08200
Testability Guidelines, TP-101A, Surface Mount Technol-
ogy Association (SMTA), August 1991
Testability Design, ADL-STD-70-001A, 7 March 1983,
Litton Amecom
Testability/Diagnostics Design Encyclopedia, George Neu-
mann, George Barthlenghi, et al, RADC TR 90 239, Sep-
tember 1990, AD-A230 067, NTIS
See also IPC documents on Electrical Testing,
Surface Mount Land Patterns/Configurations and Design
Rules
9.16 Vibration, Shock
Vibration Analysis for Electronic Equipment, 2nd Edition,
Dave S. Steinberg; J. Wiley & Sons 1989
IPC-D-279 July 1996
32
Cooling Techniques for Electronic Equipment, 2nd Edition,
Dave S. Steinberg; Wiley Interscience, 1991, ISBN 0-471-
52451-4. Chapter 8 addresses combined vibration and ther-
mal stresses.
Shock and Vibration, 3rd Edition, Cyril M. Harris, Editor,
McGraw-Hill, 1987 ISBN 0-070026801-0
Structural Analysis of Printed Circuit Board Systems, Peter
A. Engel, Springer-Verlag, 1993, ISBN 0-387-97939-5 or
3-540-97939-5
9.17 Accelerated Life Testing
Electronic Materials Handbook, Volume 1, Packaging,
ASM International; 1989; ISBN 0-87170-285-1 (V.1)
Applied Life Data Analysis, Nelson, W., John Wiley &
Sons, NY, 1982 ISBN 0-070026801-0
Accelerated Testing: Statistical Models, Test Plans, and
Data Analyses, Wayne Nelson; John Wiley & Sons, 1990;
ISBN 0471-552-775
Accelerated Testing Handbook, Technology Associates,
1987
Applied Reliability, Tobias, P. A., and Trindade, D., Van
Nostrand Reinhold, 1985, ISBN-0-442-28310-5
‘How to Plan and Analyze Accelerated Tests’’, 1900.
ASQC Basic References in Quality Control: Statistical
Techniques, Order Entry Dept., American Society for Qual-
ity Control, 310 Wisconsin Avenue, Milwaukee, WI 53203
(800) 952-6587
‘How to Analyze Reliability Data’’, Volume 6, 1983,
ASQC as above.
See also IPC publication on Accelerated Reliability Testing
of Surface Mount Solder Attachments
9.18 Solder, Solderability, Soldered Assembly Quality
See ANSI/IPC J-STD publications on various Solder, Sol-
derability, Solder Assembly Quality
9.19 Solder Mask and Conformal Coating
Contamination Effects on Electronic Products, Carl J. Taut-
scher, Marcel Dekker, 1991
Electronic Materials Handbook, Volume 1, Packaging,
Merrill L. Minges, Technical Chairman, ASM Interna-
tional, 1989; see particularly sections 6, 7 and 9.
See also IPC documents on Solder Mask, Conformal Coat-
ing, SIR, IR, Cleaning, Surface Mount Land Patterns/
Configurations and Design Rules
9.20 General Reliability
AT&T Reliability Manual, Klinger, Nakada and Menendez
Editors, VNR, 1990, ISBN 0-442-31848-0.
Handbook of Reliability Engineering and Management,
2nd Edition Ireson, Coombs and Moss, Editors, McGraw-
Hill, 1996, ISBN 0-07-012750-6
Practical Reliability Engineering, 3rd Edition, Patrick D. T.
O’Connor, John Wiley & Sons, 1995, ISBN 0-471-96025
X
Handbook of Electromechanical Product Design, P. L. Hur-
ricks, Longman Scientific & Technical, 1994, ISBN 0-470-
04083-3
July 1996 IPC-D-279
33
Appendix A
Design for Reliability (DfR) of Solder Attachments
A-1.0 SURFACE MOUNT SOLDER ATTACHMENT
RELIABILITY
The fatigue behavior of surface mount solder joints has
been investigated experimentally in numerous studies. The
results of the studies that were carried out in a manner to
assure the same damage mechanism as the mechanism
operative in typical electronic products have yielded a
mathematical solder fatigue model. This model has been
expanded and augmented to its current form, presented in
this section, as additional test results became available.
The model is for uncoated solder attachments. The com-
plexity and vast differences in conformal coatings make it
impossible to develop a generic model that considers all
the variables. Products with conformal coatings should be
evaluated using test vehicles having the same coating and
test vehicles without the coating in order to assess the
impact of the coating on reliability.
A-2.0 DAMAGE MECHANISMS AND FAILURE
The reliability of electronic assemblies depends on the reli-
ability of their individual elements and the reliability of the
mechanical thermal, and electrical interfaces (or attach-
ments) between these elements. One of these interface
types, surface mount solder attachment, is unique since the
solder joints not only provide the electrical interconnec-
tions, but are also the sole mechanical attachment of the
electronic components to the printed board and often serve
critical heat transfer functions as well.
A solder joint in isolation is neither reliable nor unreliable;
it becomes so only in the context of the electronic compo-
nents that are connected via the solder joints to the printed
board. The characteristics of these three elements - compo-
nent, substrate, and solder joint - together with the use
conditions, the design life, and the acceptable failure prob-
ability for the electronic assembly determine the reliability
of the surface mount solder attachment.
A-2.1 Solder Joints and Attachment Types
Solder joints are anything but a homogeneous structure. A
solder joint consists of a number of quite different materi-
als, many of which are only superficially characterized. A
solder joint consists of:
(1) the base metal at the printed board
(2) one or more intermetallic compounds (IMC)—
solid solutions—of a solder constituent—
typically tin (Sn)—with the printed board base
metal
(3) a layer from which the solder constituent form-
ing the printed board-side IMC(s) has been
depleted
(4) the solder grain structure, consisting of at least
two phases containing different proportions of
the solder constituents as well as any deliberate
or inadvertent contaminations
(5) a layer from which the solder constituent form-
ing the component-side IMC(s) has been
depleted
(6) one or more IMC layers of a solder constituent
with the component base metal, and
(7) the base metal at the component.
The grain structure of solder is inherently unstable. The
grains will grow in size over time as the grain structure
reduces the internal energy of a fine-grained structure. This
grain growth process is enhanced by elevated temperatures
as well as strain energy input during cyclic loading. The
grain growth process is thus an indication of the accumu-
lating fatigue damage. At the grain boundaries contami-
nants like lead oxides are concentrated; as the grains grow
these contaminants are further concentrated at the grain
boundaries, weakening these boundaries. After the con-
sumption of ~25% of the fatigue life micro-voids can be
found at the grain boundary intersections; these micro-
voids grow into micro-cracks after ~40% of the fatigue
life; these micro-cracks grow and coalesce into macro-
cracks leading to total fracture as is schematically shown in
Figure A-1.
Surface mount solder attachments exist in a wide variety of
designs. The major categories are leadless and leaded sol-
der attachments. Among the leadless solder joints a differ-
entiation has to be made between those without fillets, e.g.,
Flip-Chip C4 (Controlled Collapse Chip Connection) sol-
der joints, BGAs with C5 (Controlled Collapse Chip Car-
rier Connection) solder attachments, BGAs with high-
temperature solder (e.g., 10Sn/90Pb) balls, and CGAs with
high-temperature solder columns; and solder joints with
fillets, e.g., chip components, Metal Electrode Face compo-
nents (MELFs), and castellated leadless chip carriers. The
leaded solder attachments differ primarily in terms of their
compliancy and can be roughly categorized into compo-
nents with super-compliant leads {K
D
<~9 N/mm}, compli-
ant leads (~9 N/mm<K
D
<~90 N/mm), and non-compliant
leads {(K
D
>~90 N/mm}.
The different surface mount solder attachment types can
have significantly different failure modes. Solder joints
with essentially uniform load distributions, e.g., Flip-Chip,
BGA, CGA, show behavior as illustrated in Figure A-1.
Solder joints with non-uniform load distributions, e.g.,
those on chips components, MELFs, leadless chip carriers,
IPC-D-279 July 1996
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