Reliability Technology

Foreword by Michael Pecht ix

Series Editor's Preface xi

Preface xiii

About the Author xvii

Acknowledgements xix

1 The Origins and Evolution of Quality and Reliability 1

1.1 Sixty Years of Evolving Electronic Equipment Technology 1

1.2 Manufacturing Processes - From Manual Skills to Automation 3

1.3 Soldering Systems 4

1.4 Component Placement Machines 5

1.5 Automatic Test Equipment 5

1.6 Lean Manufacturing 5

1.7 Outsourcing 9

1.8 Electronic System Reliability - Folklore versus Reality 9

1.9 The 'Bathtub' Curve 11

1.10 The Truth about Arrhenius 13

1.11 The Demise of MIL-HDBK- 217 15

1.12 The Benefits of Commercial Off-The-Shelf (COTS) Products 18

1.13 The MoD SMART Procurement Initiative 20

1.14 Why do Items Fail? 21

1.15 The Importance of Understanding Physics of Failure (PoF) 23

Summary and Questions 23

References 25

2 Product Lifecycle Management 27

2.1 Overview 27

2.2 Project Management 29

2.3 Project Initiation 31

2.4 Project Planning 33

2.5 Project Execution 38

2.6 Project Closure 41

2.7 A Process Capability Maturity Model 42

2.8 When and How to Define The Distribution Strategy 47

2.9 Transfer of Design to Manufacturing - The High-Risk Phase 48

2.10 Outsourcing - Understanding and Minimising the Risks 49

2.11 How Product Reliability is Increasingly Threatened in the Twenty-First Century 50

Summary and Questions 51

References 52

3 The Physics of Failure 53

3.1 Overview 53

3.2 Background 54

3.3 Potential Failure Mechanisms in Materials and Components 56

3.4 Techniques for Failure Analysis of Components and Assemblies 71

3.5 Transition from Tin-Lead to Lead-Free Soldering 75

3.6 High-Temperature Electronics and Extreme-Temperature Electronics 77

3.7 Some Illustrations of Failure Mechanisms 79

Summary and Questions 86

References 87

4 Heat Transfer - Theory and Practice 89

4.1 Overview 89

4.2 Conduction 90

4.3 Convection 96

4.4 Radiation 100

4.5 Thermal Management 106

4.6 Principles of Temperature Measurement 106

4.7 Temperature Cycling and Thermal Shock 110

Summary and Questions 111

References 112

5 Shock and Vibration - Theory and Practice 113

5.1 Overview 113

5.2 Sources of Shock Pulses in the Real Environment 114

5.3 Response of Electronic Equipment to Shock Pulses 115

5.4 Shock Testing 116

5.5 Product Shock Fragility 120

5.6 Shock and Vibration Isolation Techniques 126

5.7 Sources of Vibration in the Real Environment 133

5.8 Response of Electronic Equipment to Vibration 134

5.9 Vibration Testing 134

5.10 Vibration-Test Fixtures 139

Summary and Questions 145

References 147

6 Achieving Environmental-Test Realism 149

6.1 Overview 149

6.2 Environmental-Testing Objectives 150

6.3 Environmental-Test Specifications and Standards 152

6.4 Quality Standards 157

6.5 The Role of the Test Technician 158

6.6 Mechanical Testing 159

6.7 Climatic Testing 164

6.8 Chemical and Biological Testing 168

6.9 Combined Environment Testing 169

6.10 Electromagnetic Compatibility 175

6.11 Avoiding Misinterpretation of Test Standards and Specifications 179

Summary and Questions 181

References 183

7 Essential Reliability Technology Disciplines in Design 185

7.1 Overview 185

7.2 Robust Design and Quality Loss Function 186

7.3 Six Sigma Quality 192

7.4 Concept, Parameter and Tolerance Design 195

7.5 Understanding Product Whole Lifecycle Environment 199

7.6 Defining User Requirement for Failure-Free Operation 203

7.7 Component Anatomy, Materials and Mechanical Architecture 205

7.8 Design for Testability 206

7.9 Design for Manufacturability 211

7.10 Define Product Distribution Strategy 213

Summary and Questions 215

References 216

8 Essential Reliability Technology Disciplines in Development 217

8.1 Overview 217

8.2 Understanding and Achieving Test Realism 218

8.3 Qualification Testing 219

8.4 Stress Margin Analysis and Functional Performance Stability 219

8.5 Premature Failure Stimulation 229

8.6 Accelerated Ageing vs. Accelerated Life Testing 229

8.7 Design and Proving of Distribution Packaging 232

Summary and Questions 247

References 248

9 Essential Reliability Technology Disciplines in Manufacturing 251

9.1 Overview 251

9.2 Manufacturing Planning 252

9.3 Manufacturing Process Capability 253

9.4 Manufacturing Process Management and Control 257

9.5 Non-invasive Inspection Techniques 267

9.6 Manufacturing Handling Procedures 269

9.7 Lead-Free Soldering - A True Perspective 279

9.8 Conformal Coating 281

9.9 Production Reliability Acceptance Testing 287

Summary and Questions 288

References 289

10 Environmental-Stress Screening 291

10.1 Overview 291

10.2 The Origins of ESS 291

10.3 Thermal-Stress Screening 294

10.4 Developing a Thermal-Stress Screen 313

10.5 Vibration-Stress Screening 315

10.6 Developing a Vibration-Stress Screen 317

10.7 Combined Environment-Stress Screening 326

10.8 Other Stress Screening Methodologies 327

10.9 Estimating Product Life Consumed by Stress Screening 328

10.10 An Environmental-Stress Screening Case Study 329

Summary and Questions 334

References 335

11 Some Worked Examples 337

11.1 Overview 337

11.2 Thermal Expansion Stresses Generated within a PTH Due to Temperature Cycling 340

11.3 Shear Tear-Out Stresses in Through-Hole Solder Joints 342

11.4 Axial Forces on a Through-Hole Component Lead Wire 346

11.5 SMC QFP - Solder-Joint Shear Stresses 348

11.6 Frequency and Peak Half-Amplitude Displacement Calculations 357

11.7 Random Vibration - Converting G²/Hz to G_RMS 358

11.8 Accelerated Ageing - Temperature Cycling and Vibration 360

11.9 Stress Screening - Production Vibration Fixture Design 363

References 365

Appendix 1: Physical Properties of Materials 367

Appendix 2: Unit Conversion Tables 377

Index 383