印刷电路板手册第六版

Part 1 Lead-Free Legislation

Chapter 1. Legislation and Impact on Printed Circuits 1.3

1.1 Legislation Overview / 1.3

1.2 Waste Electrical and Electronic Equipment (WEEE) / 1.3

1.3 Restriction of Hazardous Substances (RoHS) / 1.3

1.4 RoHS’ Impact on the Printed Circuit Industry / 1.6

1.5 Lead-Free perspecives / 1.10

1.6 Other Legislative Initiatives / 1.10

Part 2 Printed Circuit Technology Drivers

Chapter 2. ELECTRONIC PACKAGING AND HIGH-DENSITY

INTERCONNECTIVITY 2.3

2.1 Introduction / 2.3

2.2 Measuring the Interconnectivity Revolution (HDI) / 2.3

2.3 Hierarchy of Interconnections / 2.6

2.4 Factors Affecting Selection of Interconnections / 2.7

2.5 ICS and Packages / 2.10

2.6 Density Evaluations / 2.14

2.7 Methods to Increase PWB Density / 2.16

References / 2.21

Chapter 3. Semiconductor Packaging Technology 3.1

3.1 Introduction / 3.1

3.2 Single-Chip Packaging / 3.5

3.3 Multichip Packages / 3.15

3.4 Optical Interconnects / 3.18

3.5 High-Density/High-Performance Packaging Summary / 3.21

3.6 Roadmap Information / 3.21

References / 3.21

Chapter 4. Advanced Component Packaging 4.1

4.1 Introduction / 4.1

4.2 Lead-Free / 4.2

4.3 System-on-a-Chip (SOC) versus System-on-a-Package (SOP) / 4.3

v

For more information about this title, click here

4.4 Multichip Modules / 4.5

4.5 Multichip Packaging / 4.6

4.6 Enabling Technologies / 4.10

4.7 Acknowledgment / 4.18

References / 4.18

Chapter 5. Types of Printed Wiring Boards 5.1

5.1 Introduction / 5.1

5.2 Classification of Printed Wiring Boards / 5.1

5.3 Organic and Nonorganic Substrates / 5.3

5.4 Graphical and Discrete-Wire Boards / 5.3

5.5 Rigid and Flexible Boards / 5.5

5.6 Graphically Produced Boards / 5.6

5.7 Molded Interconnection Devices / 5.10

5.8 Plated-Through-Hole (PTH) Technologies / 5.10

5.9 Summary / 5.13

References / 5.14

Part 3 Materials

Chapter 6. Introduction to Base Materials 6.3

6.1 Introduction / 6.1

6.2 Grades and Specifications / 6.3

6.3 Properties Used to Classify Base Materials / 6.9

6.4 Types of FR-4 / 6.13

6.5 Laminate Identification Scheme / 6.14

6.6 Prepreg Identification Scheme / 6.18

6.7 Laminate and Prepreg Manufacturing Processes / 6.18

References / 6.24

Chapter 7. Base Material Components 7.1

7.1 Introduction / 7.1

7.2 Epoxy Resin Systems / 7.1

7.3 Other Resin Systems / 7.5

7.4 Additives / 7.7

7.5 Reinforcements / 7.12

7.6 Conductive Materials / 7.18

References / 7.25

Chapter 8. Properties of Base Materials 8.1

8.1 Introduction / 8.1

8.2 Thermal, Physical, and Mechanical Properties / 8.1

8.3 Electrical Properties / 8.13

References / 8.16

Chapter 9. Base Materials Performance Issues 9.1

9.1 Introduction / 9.1

9.2 Methods of Increasing Circuit Density / 9.2

9.3 Copper foil / 9.2

9.4 Laminate Constructions / 9.7

9.5 Prepreg Options and Yield-Per-Ply Values / 9.9

vi CONTENTS

9.6 Dimensional Stability / 9.10

9.7 High-Density Interconnect/Microvia Materials / 9.13

9.8 CAF Growth / 9.15

9.9 Electrical Performance / 9.22

References / 9.33

Chapter 10. The Impact of Lead-Free Assembly on Base Materials 10.1

10.1 Introduction / 10.1

10.2 RoHS Basics / 10.1

10.3 Base Material Compatibility Issues / 10.2

10.4 The Impact of Lead-Free Assembly on Base Material Components / 10.4

10.5 Critical Base Material Properties / 10.4

10.6 Impact on Printed Circuit Reliability and Material Selection / 10.18

10.7 Summary / 10.21

References / 10.22

Chapter 11. Selecting Base Materials for Lead-Free Assembly Applications 11.1

11.1 Introduction / 11.1

11.2 Pcb fabrication and Assembly Interactions / 11.1

11.3 Selecting the Right Base Material for Specific Application / 11.6

11.4 Example Application of this Tool / 11.14

11.5 Discussion of the Range of Peak Temperatures for Lead-Free Assembly / 11.15

11.6 Lead-Free Applications and Ipc-4101 Specification Sheets / 11.15

11.7 Additional Base material Options for Lead-Free Applications / 11.16

11.8 Summary / 11.17

References / 11.18

Chapter 12. Laminate Qualification and Testing 12.1

12.1 Introduction / 12.1

12.2 Industry Standards / 12.2

12.3 Laminate Test Strategy / 12.4

12.4 Initial Tests / 12.5

12.5 Full Material Characterization / 12.9

12.6 Characterization Test Plan / 12.22

12.7 Manufacturability in the Shop / 12.23

Part 4 Engineering and Design

Chapter 13. Physical Characteristics of the PCB 13.3

13.1 Classes of PCB Designs / 13.3

13.2 Types of PCBs or Packages for Electronic Circuits / 13.9

13.3 Methods of Attaching Components / 13.14

13.4 Component Package Types / 13.15

13.5 Materials Choices / 13.18

13.6 Fabrication Methods / 13.22

13.7 Choosing a Package Type and Fabrication Vendor / 13.24

Chapter 14. The PCB Design Process 14.1

14.1 Objective of the PCB Design Process / 14.1

14.2 Design Processes / 14.1

CONTENTS vii

14.3 Design Tools / 14.6

14.4 Selecting a Set of Design Tools / 14.10

14.5 Interfacing Cae, Cad, and CAMTools to Each Other / 14.11

14.6 Inputs to the Design Process / 14.11

Chapter 15. Electrical and Mechanical Design Parameters 15.1

15.1 Printed Circuit Design Requirements / 15.1

15.2 Introduction to Electrical Signal Integrity / 15.1

15.3 Introduction to Electromagnetic Compatibility / 15.3

15.4 Noise Budget / 15.4

15.5 Designing for Signal Integrity and Electromagnetic Compatibility / 15.4

15.6 Mechanical Design Requirements / 15.9

References / 15.17

Chapter 16. Current Carrying Capacity in Printed Circuits 16.1

16.1 Introduction / 16.1

16.2 Conductor (Trace) Sizing Charts / 16.1

16.3 Current Carrying Capacity / 16.2

16.4 Charts / 16.6

16.5 Baseline Charts / 16.10

16.6 Odd-Shaped Geometries and the “Swiss Cheese” Effect / 16.19

16.7 Copper Thickness / 16.20

References / 16.21

Chapter 17. PCB Design for Thermal Performance 17.1

17.1 Introduction / 17.1

17.2 The PCB as a Heat Sink Soldered to the Component / 17.2

17.3 Optimizing the PCB for Thermal Performance / 17.3

17.4 Conducting Heat to the Chassis / 17.12

17.5 PCB Requirements for High-Power Heat Sink Attach / 17.14

17.6 Modeling the Thermal Performance of the PCB / 17.15

References / 17.18

Chapter 18. Information Formating and Exchange 18.1

18.1 Introduction to Data Exchange / 18.1

18.2 The Data Exchange Process / 18.3

18.3 Data Exchange Formats / 18.9

18.4 Drivers for Evolution / 18.22

18.5 Acknowledgment / 18.23

References / 18.23

Chapter 19. Planning for Design, Fabrication, and Assembly 19.1

19.1 Introduction / 19.1

19.2 General Considerations / 19.3

19.3 New Product Design / 19.4

19.4 Layout Trade-off Planning / 19.10

19.5 PWB Fabrication Trade-off Planning / 19.17

19.6 Assembly Trade-Off Planning / 19.24

References / 19.27

viii CONTENTS

Chapter 20. Manufacturing Information, Documentation,

and Transfer Including CAM Tooling for Fab and Assembly 20.1

20.1 Introduction / 20.1

20.2 Manufacturing Information / 20.2

20.3 Initial Design Review / 20.7

20.4 Design Input / 20.15

20.5 Design Analysis and Review / 20.19

20.6 The CAM-Tooling Process / 20.19

20.7 Additional Processes / 20.31

20.8 Acknowledgment / 20.32

Chapter 21. Embedded Components 21.1

21.1 Introduction / 21.1

21.2 Definitions and Example / 21.1

21.3 Applications and Trade-Offs / 21.2

21.4 Designing for Embedded Component Applications / 21.3

21.5 Materials / 21.6

21.6 Material Supply Types / 21.9

Part 5 High Density Interconnection

Chapter 22. Introduction to High-Density Interconnection (HDI) Technology 22.3

22.1 Introduction / 22.3

22.2 Definitions / 22.3

22.3 HDI Structures / 22.7

22.4 Design / 22.11

22.5 Dielectric Materials and Coating Methods / 22.13

22.6 HDI Manufacturing Processes / 22.26

References / 22.34

Bibliography-Additional Reading / 22.35

Chapter 23. Advanced High-Density Interconnection (HDI) Technologies 23.1

23.1 Introduction / 23.1

23.2 Definitions of HDI Process Factors / 23.1

23.3 HDI Fabrication Processes / 23.3

23.4 Next-Generation HDI Processes / 23.33

References 23.37

Part 6 Fabrication

Chapter 24. Drilling Processes 24.3

24.1 Introduction / 24.3

24.2 Materials / 24.4

24.3 Machines / 24.11

24.4 Methods / 24.15

24.5 Hole Quality / 24.18

24.6 Postdrilling Inspection / 24.20

24.7 Drilling Cost Per Hole / 24.20

CONTENTS ix

Chapter 25. Precision Interconnect Drilling 25.1

25.1 Introduction / 25.1

25.2 Factors Affecting High-Density Drilling / 25.1

25.3 Laser versus Mechanical / 25.2

25.4 Factors Affecting High-Density Drilling / 25.5

25.5 Depth-Controlled Drilling Methods / 25.10

25.6 High-Aspect-Ratio Drilling / 25.10

25.7 Innerlayer Inspection of Multilayer Boards / 25.13

Chapter 26. Imaging 26.1

26.1 Introduction / 26.1

26.2 Photosensitive Materials / 26.2

26.3 Dry-Film Resists / 26.4

26.4 Liquid Photoresists / 26.7

26.5 Electrophoretic Depositable Photoresists / 26.8

26.6 Resist Processing / 26.8

26.7 Design for Manufacturing / 26.27

References / 26.29

Chapter 27. Multilayer Materials and Processing 27.1

27.1 Introduction / 27.1

27.2 Printed Wiring Board Materials / 27.2

27.3 Multilayer Construction Types / 27.16

27.4 ML-PWB Processing and Flows / 27.37

27.5 Lamination Process / 27.51

27.6 Lamination Process Control and Troubleshooting / 27.59

27.7 Lamination Overview / 27.63

27.8 ML-PWB Summary / 27.63

References / 27.63

Chapter 28. Preparing Boards for Plating 28.1

28.1 Introduction / 28.1

28.2 Process Decisions / 28.1

28.3 Process Feedwater / 28.3

28.4 Multilayer PTH Preprocessing / 28.4

28.5 Electroless Copper / 28.8

28.6 Acknowledgment / 28.11

References / 28.11

Chapter 29. Electroplating 29.1

29.1 Introduction / 29.1

29.2 Electroplating Basics / 29.1

29.3 High-Aspect Ratio Hole and Microvia Plating / 29.2

29.4 Horizontal Electroplating / 29.4

29.5 Copper Electroplating General Issues / 29.6

29.6 Acid Copper Sulfate Solutions and Operation / 29.14

29.7 Solder (Tin-Lead) Electroplating / 29.19

29.8 Tin Electroplating / 29.21

29.9 Nickel Electroplating / 29.23

29.10 Gold Electroplating / 29.25

29.11 Platinum Metals / 29.28

29.12 Silver Electroplating / 29.29

x CONTENTS

29.13 Laboratory Process control / 29.29

29.14 Acknowledgment / 29.31

References / 29.31

Chapter 30. Direct Plating 30.1

30.1 Direct Metallization Technology / 30.1

References / 30.11

Chapter 31. PWB Manufacture Using Fully Electroless Copper 31.1

31.1 Fully Electroless Plating / 31.1

31.2 The Additive Process and its Variations / 31.2

31.3 Pattern-Plating Additive / 31.2

31.4 Panel-Plate Additive / 31.7

31.5 Partly Additive / 31.8

31.6 Chemistry of Electroless Plating / 31.9

31.7 Fully Electroless Plating Issues / 31.12

References / 31.14

Chapter 32. Printed Circuit Board Surface Finishes 32.1

32.1 Introduction / 32.1

32.2 Alternative Finishes / 32.3

32.3 Hot Air Solder Level (Hasl or Hal) / 32.4

32.4 Electroless Nickel Immersion Gold (ENIG) / 32.6

32.5 Organic Solderability Preservative (OSP) / 32.8

32.6 Immersion Silver / 32.10

32.7 Immersion Tin / 32.11

32.8 Other Surface Finishes / 32.13

32.9 Assembly Compatibility / 32.14

32.10 Reliability Test Methods / 32.17

32.11 Special Topics / 32.18

32.12 Failure Modes / 32.19

32.13 Comparing Surface Finish Properties / 32.23

References / 32.23

Chapter 33. Solder Mask 33.1

33.1 Introduction / 33.1

33.2 Trends and Challenges for Solder Mask / 33.2

33.3 Types of Solder Mask / 33.3

33.4 Solder Mask Selection / 33.4

33.5 Solder Mask Application and Processing / 33.9

33.6 VIA Protection / 33.18

33.7 Solder Mask Final Properties / 33.19

33.8 Legend and Marking (Nomenclature) / 33.19

Chapter 34. Etching Process and Technologies 34.1

34.1 Introduction / 34.1

34.2 General Etching Considerations and Procedures / 34.2

34.3 Resist Removal / 34.4

34.4 Etching Solutions / 34.6

34.5 Other Materials for Board Construction / 34.18

34.6 Metals Other than Copper / 34.19

34.7 Basics of Etched Line Formation / 34.20

CONTENTS xi

34.8 Equipment and Techniques / 34.26

References / 34.29

Chapter 35. Machining and Routing 35.1

35.1 Introduction / 35.1

35.2 Punching Holes (Piercing) / 35.1

35.3 Blanking, Shearing, and Cutting of Copper-Clad Laminates / 35.3

35.4 Routing / 35.6

35.5 Scoring / 35.13

35.6 Acknowledgment / 35.15

Part 7 Bare Board Test

Chapter 36. Bare Board Test Objectives and Definitions 36.3

36.1 Introduction / 36.3

36.2 The Impact of HDI / 36.3

36.3 Why Test? / 36.4

36.4 Circuit Board Faults / 36.6

Chapter 37. Bare Board Test Methods 37.1

37.1 Introduction / 37.1

37.2 Nonelectrical Testing Methods / 37.1

37.3 Basic Electrical Testing Methods / 37.2

37.4 Specialized Electrical Testing Methods / 37.9

37.5 Data and Fixture Preparation / 37.13

37.6 Combined Testing Methods / 37.20

Chapter 38. Bare Board Test Equipment 38.1

38.1 Introduction / 38.1

38.2 System Alternatives / 38.1

38.3 Universal Grid Systems / 38.3

38.4 Flying-Probe/Moving-Probe Test Systems / 38.17

38.5 Verification and Repair / 38.21

38.6 Test Department Planning and Management / 38.22

Chapter 39. HDI Bare Board Special Testing Methods 39.1

39.1 Introduction / 39.1

39.2 Fine-Pitch Tilt-Pin Fixtures / 39.2

39.3 Bending Beam Fixtures / 39.3

39.4 Flying Probe / 39.3

39.5 Coupled Plate / 39.3

39.6 Shorting Plate / 39.4

39.7 Conductive Rubber Fixtures / 39.5

39.8 Optical Inspection / 39.5

39.9 Noncontact Test Methods / 39.5

39.10 Combinational Test Methods / 39.7

xii CONTENTS

Part 8 Assembly

Chapter 40. Assembly Processes 40.3

40.1 Introduction / 40.3

40.2 Through-Hole Technology / 40.5

40.3 Surface-Mount Technology / 40.16

40.4 Odd-Form Component Assembly / 40.42

40.5 Process Control / 40.48

40.6 Process Equipment Selection / 40.54

40.7 Repair and Rework / 40.57

40.8 Conformal Coating, Encapsulation, and Underfill Materials / 40.64

40.9 Acknowledgment / 40.66

Chapter 41. Conformal Coating 41.1

41.1 Introduction / 41.1

41.2 Types of Conformal Coatings / 41.3

41.3 Product Preparation / 41.6

41.4 Application Processes / 41.7

41.5 Cure, Inspection, and Finishing / 41.11

41.6 Repair Methods / 41.13

41.7 Design for Conformal Coating / 41.14

References / 41.17

Part 9 Solderability Technology

Chapter 42. Solderability: Incoming Inspection and Wet Balance Technique 42.3

42.1 Introduction / 42.3

42.2 Solderability / 42.4

42.3 Solderability Testing—a Scientific Approach / 42.8

42.4 The Influence of Temperature on Test Results / 42.13

42.5 Interpreting the Results:Wetting Balance Solderability Testing / 42.14

42.6 Globule Testing / 42.15

42.7 PCB Surface Finishes and Solderability Testing / 42.16

42.8 Component Solderability / 42.22

Chapter 43. Fluxes and Cleaning 43.1

43.1 Introduction / 43.1

43.2 Assembly Process / 43.2

43.3 Surface Finishes / 43.3

43.4 Soldering Flux / 43.5

43.5 Flux Form Versus Soldering Process / 43.6

43.6 Rosin Flux / 43.7

43.7 Water-Soluble Flux / 43.8

43.8 Low Solids Flux / 43.9

43.9 Cleaning Issues / 43.10

43.10 Summary / 43.12

References / 43.12

CONTENTS xiii

Part 10 Solder Materials and Processes

Chapter 44. Soldering Fundamentals 44.3

44.1 Introduction / 44.3

44.2 Elements of a Solder Joint / 44.4

44.3 The Solder Connection to the Circuit Board / 44.4

44.4 The solder Connection to the Electrical Component / 44.5

44.5 Common Metal-Joining Methods / 44.5

44.6 Solder Overview / 44.9

44.7 Soldering Basics / 44.9

Chapter 45. Soldering Materials and Metallurgy 45.1

45.1 Introduction / 45.1

45.2 Solders / 45.2

45.3 Solder Alloys and Corrosion / 45.4

45.4 PB-Free Solders: Search for Alternatives and Implications / 45.5

45.5 PB-Free Elemental Alloy Candidates / 45.5

45.6 Board Surface Finishes / 45.11

References / 45.19

Chapter 46. Solder Fluxes 46.1

46.1 Introduction to Fluxes / 46.1

46.2 Flux Activity and Attributes / 46.2

46.3 Flux: Ideal Versus Reality / 46.3

46.4 Flux Types / 46.4

46.5 Water-Clean (Aqueous) Fluxes / 46.4

46.6 No-Clean Flux / 46.7

46.7 Other Fluxing Caveats / 46.9

46.8 Soldering Atmospheres / 46.12

References / 46.15

Chapter 47. Soldering Techniques 47.1

47.1 Introduction / 47.1

47.2 Mass Soldering Methods / 47.1

47.3 Oven Reflow Soldering / 47.1

47.4 Wave Soldering / 47.28

47.5 Wave Solder Defects / 47.39

47.6 Vapor-Phase Reflow Soldering / 47.42

47.7 Laser Reflow Soldering / 47.43

47.8 Tooling and the Need for Coplanarity and Intimate Contact / 47.50

47.9 Additional Information Sources / 47.53

47.10 Hot-Bar Soldering / 47.53

47.11 Hot-Gas Soldering / 47.58

47.12 Ultrasonic Soldering / 47.59

References / 47.61

Chapter 48. Soldering Repair and Rework 48.1

48.1 Introduction / 48.1

48.2 Hot-Gas Repair / 48.1

xiv CONTENTS

48.3 Manual Solder Fountain / 48.5

48.4 Automated Solder Fountain / 48.6

48.5 Laser / 48.6

48.6 Considerations for Repair / 48.6

Reference / 48.7

Part 11 Nonsolder Interconnection

Chapter 49. Press-Fit Interconnection 49.3

49.1 Introduction / 49.3

49.2 The Rise of Press-Fit Technology / 49.3

49.3 Compliant Pin Configurations / 49.4

49.4 Press-Fit Considerations / 49.6

49.5 Press-Fit Pin Materials / 49.7

49.6 Surface Finishes and Effects / 49.8

49.7 Equipment / 49.10

49.8 Assembly Process / 49.11

49.9 Press Routines / 49.12

49.10 PWB Design and Board Procurement Tips / 49.14

49.11 Press-Fit Process Tips / 49.15

49.12 Inspection and Testing / 49.16

49.13 Soldering and Press-Fit Pins / 49.17

References / 49.17

Chapter 50. Land Grid Array Interconnect 50.1

50.1 Introduction / 50.1

50.2 LGA and the Environment / 50.1

50.3 Elements of the LGA System / 50.2

50.4 Assembly / 50.5

50.5 Printed Circuit Assembly (PCA) Rework / 50.7

50.6 Design Guidelines / 50.8

Reference / 50.8

Part 12 Quality

Chapter 51. Acceptability and Quality of Fabricated Boards 51.3

51.1 Introduction / 51.3

51.2 Specific Quality and Acceptability Criteria by PCB Type / 51.4

51.3 Methods for Verification of Acceptability / 51.6

51.4 Inspection Lot Formation / 51.7

51.5 Inspections Categories / 51.8

51.6 Acceptability and Quality After Simulated Solder Cycle(s) / 51.8

51.7 Nonconforming PCBS and Material Review Board (MRB) Function / 51.10

51.8 The Cost of the Assembled PCB / 51.11

51.9 How to Develop Acceptability and Quality Criteria / 51.11

51.10 Class of Service / 51.13

51.11 Inspection Criteria / 51.13

51.12 Reliability Inspection Using Accelerated Environmental Exposure / 51.32

CONTENTS xv

Chapter 52. Acceptability of Printed Circuit Board Assemblies 52.1

52.1 Understanding Customer Requirements / 52.1

52.2 Handling to Protect the PCBA / 52.7

52.3 PCBA Hardware Acceptability Considerations / 52.10

52.4 Component Installation or Placement Requirements / 52.15

52.5 Component and PCB Solderability Requirements / 52.25

52.6 Solder-Related Defects / 52.25

52.7 PCBA Laminate Condition, Cleanliness, and Marking Requirements / 52.32

52.8 PCBA Coatings / 52.34

52.9 Solderless Wrapping of Wire to Posts (Wire Wrap) / 52.35

52.10 PCBA Modifications / 52.37

References / 52.39

Chapter 53. Assembly Inspection 53.1

53.1 Introduction / 53.1

53.2 Definition of Defects, Faults, Process Indicators, and Potential Defects / 53.3

53.3 Reasons for Inspection / 53.4

53.4 Lead-Free Impact on Inspection / 53.6

53.5 Miniaturization and Higher Complexity / 53.8

53.6 Visual Inspection / 53.8

53.7 Automated Inspection / 53.12

53.8 Three-Dimensional Automated Solder Paste Inspection / 53.14

53.9 PRE-Reflow Aoi / 53.16

53.10 Post-Reflow Automated Inspection / 53.17

53.11 Implementation of Inspection Systems / 53.23

53.12 Design Implications of Inspection Systems / 53.24

References / 53.25

Chapter 54. Design for Testing 54.1

54.1 Introduction / 54.1

54.2 Definitions / 54.2

54.3 AD HOC Design for Testability / 54.2

54.4 Structured Design for Testability / 54.4

54.5 Standards-Based Testing / 54.5

References / 54.12

Chapter 55. Loaded Board Testing 55.1

55.1 Introduction / 55.1

55.2 The process of Test / 55.1

55.3 Definitions / 55.4

55.4 Testing Approaches / 55.7

55.5 In-Circuit Test Techniques / 55.11

55.6 Alternatives to Conventional Electrical Tests / 55.17

55.7 Tester Comparison / 55.19

References / 55.20

Part 13 Reliability

Chapter 56. Conductive Anodic Filament Formation 56.3

56.1 Introduction / 56.3

56.2 Understanding CAF Formation / 56.3

xvi CONTENTS

56.3 Electrochemical Migration and Formation of CAF / 56.7

56.4 Factors that Affect CAF Formation / 56.10

56.5 Test Method for CAF-Resistant Materials / 56.14

56.6 Manufacturing Tolerance Considerations / 56.14

References / 56.15

Chapter 57. Reliability of Printed Circuit Assemblies 57.1

57.1 Fundamentals of Reliability / 57.2

57.2 Failure Mechanisms of PCBS and Their Interconnects / 57.4

57.3 Influence of Design on Reliability / 57.19

57.4 Impact of PCB Fabrication and Assembly on Reliability / 57.20

57.5 Influence of Materials Selection on Reliability / 57.27

57.6 Burn-in, Acceptance Testing, and Accelerated Reliability Testing / 57.36

57.7 Summary / 57.45

References / 57.45

Further Reading / 57.47

Chapter 58. Component-to-PWB Reliability: The Impact of Design

Variables and Lead Free 58.1

58.1 Introduction / 58.1

58.2 Packaging Challenges / 58.2

58.3 Variables that Impact Reliability / 58.5

References / 58.30

Chapter 59. Component-to-PWB Reliability: Estimating Solder-Joint

Reliability and the Impact of Lead-Free Solders 59.1

59.1 Introduction / 59.1

59.2 Thermomechanical Reliability / 59.3

59.3 Mechanical Reliability / 59.20

59.4 Finite Element Analysis (FEA) / 59.27

References / 59.35

Part 14 Environmental Issues

Chapter 60. Process Waste Minimization and Treatment 60.3

60.1 Introduction / 60.3

60.2 Regulatory Compliance / 60.3

60.3 Major Sources and Amounts of Wastewater

in a Printed Circuit Board Fabrication Facility / 60.5

60.4 Waste Minimization / 60.6

60.5 Pollution Prevention Techniques / 60.8

60.6 Recycling and Recovery Techniques / 60.15

60.7 Alternative Treatments / 60.18

60.8 Chemical Treatment Systems / 60.21

60.9 Advantages and Disadvantages of Various Treatment Alternatives / 60.26

CONTENTS xvii

Part 15 Flexible Circuits

Chapter 61. Flexible Circuit Applications and Materials 61.3

61.1 Introduction to Flexible Circuits / 61.3

61.2 Applications of Flexible Circuits / 61.6

61.3 High-Density Flexible Circuits / 61.6

61.4 Materials for Flexible Circuits / 61.8

61.5 Substrate Material Properties / 61.9

61.6 Conductor Materials / 61.13

61.7 Copper-Clad Laminates / 61.14

61.8 Coverlay Material / 61.19

61.9 Stiffener Materials / 61.22

61.10 Adhesive materials / 61.22

61.11 Restriction of Hazardous Substances

(RoHS) Issues / 61.23

Chapter 62. Design of Flexible Circuits 62.1

62.1 Introduction / 62.1

62.2 Design Procedure / 62.1

62.3 Types of Flexible Circuits / 62.2

62.4 Circuit Designs for Flexibility / 62.12

62.5 Electrical Design of the Circuits / 62.15

62.6 Circuit Designs for Higher Reliability / 62.16

62.7 Circuit Designs for RoHS Compliance / 62.17

Chapter 63. Manufacturing of Flexible Circuits 63.1

63.1 Introduction / 63.1

63.2 Special Issues with HDI Flexible Circuits / 63.1

63.3 Basic Process Elements / 63.3

63.4 New Processes for Fine Traces / 63.14

63.5 Coverlay Processes / 63.24

63.6 Surface Treatment / 63.30

63.7 Blanking / 63.31

63.8 Stiffener Processes / 63.33

63.9 Packaging / 63.33

63.10 Roll-to-Roll Manufacturing / 63.34

63.11 Dimension Control / 63.36

Chapter 64. Termination of Flexible Circuits 64.1

64.1 Introduction / 64.1

64.2 Selection of Termination Technologies / 64.1

64.3 Permanent Connections / 64.4

64.4 Semipermanent Connections / 64.11

64.5 Nonpermanent Connections / 64.13

64.6 High-Density Flexible Circuit Termination / 64.20

Chapter 65. Multilayer Flex and Rigid/Flex 65.1

65.1 Introduction / 65.1

65.2 Multilayer Rigid/flex / 65.1

xviii CONTENTS

Chapter 66. Special Constructions of Flexible Circuits 66.1

66.1 Introduction / 66.1

66.2 Flying-Lead Construction / 66.1

66.3 Tape Automated Bonding / 66.8

66.4 Microbump Arrays / 66.10

66.5 Thick-Film Conductor Flex Circuits / 66.12

66.6 Shielding of the Flexible Cables / 66.13

66.7 Functional Flexible Circuits / 66.14

Chapter 67. Quality Assurance of Flexible Circuits 67.1

67.1 Introduction / 67.1

67.2 Basic Concepts in Flexible Circuit Quality Assurance / 67.1

67.3 Automatic Optical Inspection Systems / 67.2

67.4 Dimensional Measurements / 67.3

67.5 Electrical Tests / 67.3

67.6 Inspection Sequence / 67.3

67.7 Raw Materials / 67.6

67.8 Flexible Circuit Feature Inspection / 67.6

67.9 Standards and Specifications for Flexible Circuits / 67.8

Appendix A.1

Glossary G.1

Index I.1