Foreword by Jianbin Luo xv

Foreword by C. P. Wong xvii

Foreword by Zhigang Suo xix

Preface to Second Edition xxi

Preface to First Edition xxiii

Acknowledgments xxv

About the Authors xxvii

Part I Mechanics and Modeling 1
1 Constitutive Models and Finite Element Method 3
1.1 Constitutive Models for Typical Materials 3
1.1.1 Linear Elasticity 3
1.1.2 Elastic-Visco-Plasticity 5
1.2 Finite Element Method 9
1.2.1 Basic Finite Element Equations 9
1.2.2 Nonlinear Solution Methods 12
1.2.3 Advanced Modeling Techniques in Finite Element Analysis 14
1.2.4 Finite Element Applications in Semiconductor Packaging Modeling 17
1.3 Chapter Summary 18
References 19

2 Material and Structural Testing for Small Samples 21
2.1 Material Testing for Solder Joints 21
2.1.1 Specimens 21
2.1.2 A Thermo-Mechanical Fatigue Tester 23
2.1.3 Tensile Test 24
2.1.4 Creep Test 26
2.1.5 Fatigue Test 31
2.2 Scale Effect of Packaging Materials 32
2.2.1 Specimens 33
2.2.2 Experimental Results and Discussions 34
2.2.3 Thin Film Scale Dependence for Polymer Thin Films 39
2.3 Two-Ball Joint Specimen Fatigue Testing 41
2.4 Chapter Summary 41
References 43

3 Constitutive and User-Supplied Subroutines for Solders Considering Damage Evolution 45
3.1 Constitutive Model for Tin-Lead Solder Joint 45
3.1.1 Model Formulation 45
3.1.2 Determination of Material Constants 47
3.1.3 Model Prediction 49
3.2 Visco-Elastic-Plastic Properties and Constitutive Modeling of Underfills 50
3.2.1 Constitutive Modeling of Underfills 50
3.2.2 Identification of Material Constants 55
3.2.3 Model Verification and Prediction 55
3.3 A Damage Coupling Framework of Unified Viscoplasticity for the Fatigue of Solder Alloys 56
3.3.1 Damage Coupling Thermodynamic Framework 56
3.3.2 Large Deformation Formulation 62
3.3.3 Identification of the Material Parameters 63
3.3.4 Creep Damage 66
3.4 User-Supplied Subroutines for Solders Considering Damage Evolution 67
3.4.1 Return-Mapping Algorithm and FEA Implementation 67
3.4.2 Advanced Features of the Implementation 69
3.4.3 Applications of the Methodology 71
3.5 Chapter Summary 76
References 76

4 Accelerated Fatigue Life Assessment Approaches for Solders in Packages 79
4.1 Life Prediction Methodology 79
4.1.1 Strain-Based Approach 80
4.1.2 Energy-Based Approach 82
4.1.3 Fracture Mechanics-Based Approach 82
4.2 Accelerated Testing Methodology 82
4.2.1 Failure Modes via Accelerated Testing Bounds 83
4.2.2 Isothermal Fatigue via Thermal Fatigue 83
4.3 Constitutive Modeling Methodology 83
4.3.1 Separated Modeling via Unified Modeling 83
4.3.2 Viscoplasticity with Damage Evolution 84
4.4 Solder Joint Reliability via FEA 84
4.4.1 Life Prediction of Ford Joint Specimen 84
4.4.2 Accelerated Testing: Insights from Life Prediction 87
4.4.3 Fatigue Life Prediction of a PQFP Package 91
4.5 Life Prediction of Flip-Chip Packages 93
4.5.1 Fatigue Life Prediction with and without Underfill 93
4.5.2 Life Prediction of Flip-Chips without Underfill via Unified and Separated Constitutive Modeling 95
4.5.3 Life Prediction of Flip-Chips under Accelerated Testing 96
4.6 Chapter Summary 99
References 99

5 Multi-Physics and Multi-Scale Modeling 103
5.1 Multi-Physics Modeling 103
5.1.1 Direct-Coupled Analysis 103
5.1.2 Sequential Coupling 104
5.2 Multi-Scale Modeling 106
5.3 Chapter Summary 107
References 108

6 Modeling Validation Tools 109
6.1 Structural Mechanics Analysis 109
6.2 Requirements of Experimental Methods for Structural Mechanics Analysis 111
6.3 Whole Field Optical Techniques 112
6.4 Thermal Strains Measurements Using Moire Interferometry 113
6.4.1 Thermal Strains in a Plastic Ball Grid Array (PBGA) Interconnection 113
6.4.2 Real-Time Thermal Deformation Measurements Using Moire Interferometry 116
6.5 In-Situ Measurements on. Micro-Machined Sensors 116
6.5.1 Micro-Machined Membrane Structure in a Chemical Sensor 116
6.5.2 In-Situ Measurement Using Twyman-Green Interferometry 118
6.5.3 Membrane Deformations due to Power Cycles 118
6.6 Real-Time Measurements Using Speckle Interferometry 119
6.7 Image Processing and Computer Aided Optical Techniques 120
6.7.1 Image ftocessing for Fringe Analysis 120
6.7.2 Phase Shifting Technique for Increasing Displacement Resolution 120
6.8 Real-Time Thermal-Mechanical Loading Tools 123
6.8.1 Micro-Mechanical Testing 123
6.8.2 Environmental Chamber 124
6.9 Warpage Measurement Using PM-SM System 124
6.9.1 Shadow Moire and Project Moire Setup 125
6.9.2 Warpage Measurement of a BGA, TXvo Crowded PCBs 127
6.10 Chapter Summary 131
References 131

7 Application of Fracture Mechanics 135
7.1 Fundamental of Fracture Mechanics 135
7.1.1 Energy Release Rate 136
7.1.2 J Integral 138
7.1.3 Interfacial Crack 139
7.2 Bulk Material Cracks in Electronic Packages 141
7.2.1 Background 141
7.2.2 Crack Propagation in Ceramic/Adhesive/Glass System 142
7.2.3 Results 146
7.3 Interfacial Fracture Toughness 148
7.3.1 Background 148
7.3.2 Interfacial Fracture Toughness of Flip-Chip Package 0between Passivated Silicon Chip and Underfill 150
7.4 Three-Dimensional Energy Release Rate Calculation 159
7.4.1 Fracture Analysis 160
7.4.2 Results and Comparison 160
7.5 Chapter Summary 165
References 165

8 Concurrent Engineering for Microelectronics 169
8.1 Design Optimization 169
8.2 New Developments and Trends in Integrated Design Tools 179
8.3 Chapter Summary 183
References 183

Part II Modeling in Microelectronic Packaging and Assembly 185
9 Typical IC Packaging and Assembly Processes 187
9.1 Wafer Process and Thinning 188
9.1.1 Wafer Process Stress Models 188
9.1.2 Thin Film Deposition 189
9.1.3 Backside Grind for Thinning 191
9.2 Die Pick Up 193
9.3 Die Attach 198
9.3.1 Material Constitutive Relations 200
9.3.2 Modeling and Numerical Strategies 201
9.3.3 FEA Simulation Result of Flip-Chip Attach 204
9.4 Wire Bonding 206
9.4.1 Assumption, Material Properties and Method of Analysis 207
9.4.2 Wire Bonding Process with Different Parameters 208
9.4.3 Impact of Ultrasonic Amplitude 210
9.4.4 Impact of Ultrasonic Frequency 212
9.4.5 Impact of Friction Coefficients between Bond Pad and FAB 214
9.4.6 Impact of Different Bond Pad Thickness 217
9.4.7 Impact of Different Bond Pad Structures 217
9.4.8 Modeling Results and Discussion for Cooling Substrate Temperature after Wire Bonding 221
9.5 Molding 223
9.5.1 Molding Flow Simulation 223
9.5.2 Curing Stress Model 230
9.5.3 Molding Ejection and Clamping Simulation 236
9.6 Leadframe Forming/Singulation 241
9.6.1 Euler Forward versus Backward Solution Method 242
9.6.2 Punch Process Setup 242
9.6.3 Punch Simulation by ANSYS Implicit 244
9.6.4 Punch Simulation by LS-DYNA 246
9.6.5 Experimental Data 248
9.7 Chapter Summary 252
References 252

10 Opto Packaging and Assembly 255
10.1 Silicon Substrate Based Opto Package Assembly 255
10.1.1 State of the Technology 255
10.1.2 Monte Carlo Simulation of Bonding/Soldering Process 256
10.1.3 Effect of Matching Fluid 256
10.1.4 Effect of the Encapsulation 258
10.2 Welding of a Pump Laser Module 258
10.2.1 Module Description 258
10.2.2 Module Packaging Process Flow 258
10.2.3 Radiation Heat Transfer Modeling for Hermetic Sealing Process 259
10.2.4 Two-Dimensional FEA Modeling for Hermetic Sealing 260
10.2.5 Cavity Radiation Analyses Results and Discussions 262
10.3 Chapter Summary 264
References 264