An understanding of modeling and simulation techniques is becoming increasingly essential for engineers and researchers working with microelectronic packaging, interconnection design, and assembly manufacturing. This book shows for the first time how to model and simulate various processes in manufacturing, reliability, and testing.

Foreword by C. P. Wong xiii Foreword by Zhigang Suo xv Preface xvii Acknowledgments xix About the Authors xxi 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 Processing 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, Two 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 between 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 11 MEMS and MEMS Package Assembly 267 11.1 A Pressure Sensor Packaging (Deformation and Stress) 267 11.1.1 Piezoresistance in Silicon 268 11.1.2 Finite Element Modeling and Geometry 270 11.1.3 Material Properties 270 11.1.4 Results and Discussion 271 11.2 Mounting of Pressure Sensor 273 11.2.1 Mounting Process 273 11.2.2 Modeling 274 11.2.3 Results 276 11.2.4 Experiments and Discussions 277 11.3 Thermo-Fluid Based Accelerometer Packaging 279 11.3.1 Device Structure and Operation Principle 279 11.3.2 Linearity Analysis 280 11.3.3 Design Consideration 284 11.3.4 Fabrication 285 11.3.5 Experiment 285 11.4 Plastic Packaging for a Capacitance Based Accelerometer 288 11.4.1 Micro-Machined Accelerometer 289 11.4.2 Wafer-Level Packaging 290 11.4.3 Packaging of Capped Accelerometer 296 11.5 Tire Pressure Monitoring System (TPMS) Antenna 303 11.5.1 Test of TPMS System with Wheel Antenna 304 11.5.2 3D Electromagnetic Modeling of Wheel Antenna 306 11.5.3 Stress Modeling of Installed TPMS 307 11.6 Thermo-Fluid Based Gyroscope Packaging 310 11.6.1 Operating Principle and Design 312 11.6.2 Analysis of Angular Acceleration Coupling 313 11.6.3 Numerical Simulation and Analysis 314 11.7 Microjets for Radar and LED Cooling 316 11.7.1 Microjet Array Cooling System 319 11.7.2 Preliminary Experiments 320 11.7.3 Simulation and Model Verification 322 11.7.4 Comparison and Optimization of Three Microjet Devices 324 11.8 Air Flow Sensor 327 11.8.1 Operation Principle 329 11.8.2 Simulation of Flow Conditions 331 11.8.3 Simulation of Temperature Field on the Sensor Chip Surface 333 11.9 Direct Numerical Simulation of Particle Separation by Direct Current Dielectrophoresis 335 11.9.1 Mathematical Model and Implementation 335 11.9.2 Results and Discussion 339 11.10 Modeling of Micro-Machine for Use in Gastrointestinal Endoscopy 341 11.10.1 Methods 343 11.10.2 Results and Discussion 348 11.11 Chapter Summary 353 References 354 12 System in Package (SIP) Assembly 361 12.1 Assembly Process of Side by Side Placed SIP 361 12.1.1 Multiple Die Attach Process 361 12.1.2 Cooling Stress and Warpage Simulation after Molding 365 12.1.3 Stress Simulation in Trim Process 366 12.2 Impact of the Nonlinear Materials Behaviors on the Flip-Chip Packaging Assembly Reliability 369 12.2.1 Finite Element Modeling and Effect of Material Models 371 12.2.2 Experiment 374 12.2.3 Results and Discussions 375 12.3 Stacked Die Flip-Chip Assembly Layout and the Material Selection 381 12.3.1 Finite Element Model for the Stack Die FSBGA 383 12.3.2 Assembly Layout Investigation 385 12.3.3 Material Selection 389 12.4 Chapter Summary 393 References 393 Part III Modeling in Microelectronic Package Reliability and Test 395 13 Wafer Probing Test 397 13.1 Probe Test Model 397 13.2 Parameter Probe Test Modeling Results and Discussions 400 13.2.1 Impact of Probe Tip Geometry Shapes 401 13.2.2 Impact of Contact Friction 403 13.2.3 Impact of Probe Tip Scrub 403 13.3 Comparison Modeling: Probe Test versus Wire Bonding 406 13.4 Design of Experiment (DOE) Study and Correlation of Probing Experiment and FEA Modeling 409 13.5 Chapter Summary 411 References 412 14 Power and Thermal Cycling, Solder Joint Fatigue Life 413 14.1 Die Attach Process and Material Relations 413 14.2 Power Cycling Modeling and Discussion 413 14.3 Thermal Cycling Modeling and Discussion 420 14.4 Methodology of Solder Joint Fatigue Life Prediction 426 14.5 Fatigue Life Prediction of a Stack Die Flip-Chip on Silicon (FSBGA) 427 14.6 Effect of Cleaned and Non-Cleaned Situations on the Reliability of Flip-Chip Packages 434 14.6.1 Finite Element Models for the Clean and Non-Clean Cases 435 14.6.2 Model Evaluation 435 14.6.3 Reliability Study for the Solder Joints 437 14.7 Chapter Summary 438 References 439 15 Passivation Crack Avoidance 441 15.1 Ratcheting-Induced Stable Cracking: A Synopsis 441 15.2 Ratcheting in Metal Films 445 15.3 Cracking in Passivation Films 447 15.4 Design Modifications 452 15.5 Chapter Summary 452 References 452 16 Drop Test 453 16.1 Controlled Pulse Drop Test 453 16.1.1 Simulation Methods 454 16.1.2 Simulation Results 457 16.1.3 Parametric Study 458 16.2 Free Drop 460 16.2.1 Simulated Drop Test Procedure 460 16.2.2 Modeling Results and Discussion 461 16.3 Portable Electronic Devices Drop Test and Simulation 467 16.3.1 Test Set-Up 467 16.3.2 Modeling and Simulation 468 16.3.3 Results 470 16.4 Chapter Summary 470 References 471 17 Electromigration 473 17.1 Basic Migration Formulation and Algorithm 473 17.2 Electromigration Examples from IC Device and Package 477 17.2.1 A Sweat Structure 477 17.2.2 A Flip-Chip CSP with Solder Bumps 480 17.3 Chapter Summary 496 References 497 18 Popcorning in Plastic Packages 499 18.1 Statement of Problem 499 18.2 Analysis 501 18.3 Results and Comparisons 503 18.3.1 Behavior of a Delaminated Package due to Pulsed Heating-Verification 503 18.3.2 Convergence of the Total Strain Energy Release Rate 504 18.3.3 Effect of Delamination Size and Various Processes for a Thick Package 505 18.3.4 Effect of Moisture Expansion Coefficient 514 18.4 Chapter Summary 515 References 516 Part IV Modern Modeling and Simulation Methodologies: Application to Nano Packaging 519 19 Classical Molecular Dynamics 521 19.1 General Description of Molecular Dynamics Method 521 19.2 Mechanism of Carbon Nanotube Welding onto the Metal 522 19.2.1 Computational Methodology 522 19.2.2 Results and Discussion 523 19.3 Applications of Car–Parrinello Molecular Dynamics 530 19.3.1 Car–Parrinello Simulation of Initial Growth Stage of Gallium Nitride on Carbon Nanotube 530 19.3.2 Effects of Mechanical Deformation on Outer Surface Reactivity of Carbon Nanotubes 534 19.3.3 Adsorption Configuration of Magnesium on Wurtzite Gallium Nitride Surface Using First-Principles Calculations 539 19.4 Nano-Welding by RF Heating 544 19.5 Chapter Summary 548 References 548 Index 553

Although there is increasing need for modeling and simulation in the IC package design phase, most assembly processes and various reliability tests are still based on the time consuming "test and try out" method to obtain the best solution. Modeling and simulation can easily ensure virtual Design of Experiments (DoE) to achieve the optimal solution. This has greatly reduced the cost and production time, especially for new product development. Using modeling and simulation will become increasingly necessary for future advances in 3D package development.  In this book, Liu and Liu allow people in the area to learn the basic and advanced modeling and simulation skills to help solve problems they encounter.   Models and simulates numerous processes in manufacturing, reliability and testing for the first timeProvides the skills necessary for virtual prototyping and virtual reliability qualification and testingDemonstrates concurrent engineering and co-design approaches for advanced engineering design of microelectronic productsCovers packaging and assembly for typical ICs, optoelectronics, MEMS, 2D/3D SiP, and nano interconnectsAppendix and color images available for download from the book's companion website Liu and Liu have optimized the book for practicing engineers, researchers, and post-graduates in microelectronic packaging and interconnection design, assembly manufacturing, electronic reliability/quality, and semiconductor materials. Product managers, application engineers, sales and marketing staff, who need to explain to customers how the assembly manufacturing, reliability and testing will impact their products, will also find this book a critical resource. Appendix and color version of selected figures can be found at www.wiley.com/go/liu/packaging