INVESTIGATION AND PREDICTION OF SOLDER JOINT RELIABILITY FOR CERAMIC AREA ARRAY PACKAGES UNDER THERMAL CYCLING, POWER CYCLING, AND VIBRATION ENVIRONMENTS A Dissertation Presented to The Academic Faculty by Andrew Eugene Perkins In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the School of G.W. Woodruff School of Mechanical Engineering Georgia Institute of Technology May 2007 COPYRIGHT 2007 BY ANDREW E. PERKINS INVESTIGATION AND PREDICTION OF SOLDER JOINT RELIABILITY FOR CERAMIC AREA ARRAY PACKAGES UNDER THERMAL CYCLING, POWER CYCLING, AND VIBRATION ENVIRONMENTS Approved by: Prof. Suresh K. Sitaraman, Advisor Prof. Daniel Baldwin School of Mechanical Engineering School of Mechanical Engineering Georgia Institute of Technology Georgia Institute of Technology Prof. Rao Tummala Prof. Richard W. Neu School of Electrical and Computer School of Mechanical Engineering Engineering & School of Materials Science Georgia Institute of Technology and Engineering Georgia Institute of Technology Dr. Kamal Sikka Thermal/Mechanical Design IBM Microelectronics Date Approved: March 27, 2007 Dedicated to my Grandfather William Dana Perkins. He taught me that everything holds a mystery. The pursuit of that mystery leads to knowledge, and that knowledge leads again to mystery. This infinite circle is his joy and pursuit-contagious to all those around him. I feel his joy now as I complete this body of knowledge and enter into another mystery. ACKNOWLEDGEMENTS I began this PhD thinking I was going to attain all the necessary knowledge and skills to complete a PhD. However, I soon realized that pursing a PhD is not worthwhile, nor an achievable goal to pursue by oneself. I have been blessed with many supporters along the way. Without them I would never have finished this work. I would first like to acknowledge my advisor, Dr. Sitaraman, for taking me in as an undergraduate student and giving me an open door to working with him as a graduate student. I appreciate his honesty, encouragement when I was off-track, and willingness to put forward the necessary effort and endurance to help me complete this work. In addition to Dr. Sitaraman, I would like to thank the other members of my PhD Reading Committee: Dr. Tummala, Dr. Baldwin, Dr. Neu, and Dr. Sikka. They provided valuable input, generous use of their lab equipment, and helpful feedback during the process. I would like to thank the following companies: Compaq/HP for initiating the project, funding, and provided test vehicles; the Package Research Center of Georgia Tech for use of equipment and helpful daily interaction; Northrop Grumman and BAE Systems for providing environmental condition data and funding; IBM Microsystems for a valuable summer internship and support of this work; and Micron Technologies for allowing me to finish this work while working full-time as an employee. I would like to thank my wife, Lynn, for her support and giving me many reasons to have enjoyed this journey as deeply as I have. The cyclical nature of a graduate student’s life and emotions is often more harsh on the supporting partner. I can’t think of a greater blessing than to have had her support and willingness to sacrifice so much for this work. iv I would like to thank my parents giving me so many open doors in life. They have encouraged me along the way and now they get to reap the benefits of their work in me as Lynn and I strive to raise their grandsons with the same encouragement they gave to me. I would also like to thank my innumerable friends and family members who have made life worth living. One cannot grow in life without the love of others. v TABLE OF CONTENTS ACKNOWLEDGEMENTS………………………………………………………………iv LIST OF TABLES………………………………………………………………………..ix LIST OF FIGURES……………………………………………………………………....xi LIST OF ABBREVIATIONS…………………………………………………………...xvi LIST OF SYMBOLS……….………………………………………………………......xvii SUMMARY ………………………………………………………………………….…xix CHAPTER 1. INTRODUCTION .......................................................................................1 CHAPTER 2. LITERATURE REVIEW ............................................................................5 2.1. Thermal Cycling ..................................................................................................5 2.2. Power Cycling......................................................................................................8 2.3. Vibration Environment ......................................................................................13 2.4. Combined and Sequential Thermal-Mechanical, Power Cycling, and Vibration Environments .................................................................................................................15 CHAPTER 3. RESEARCH GAPS, RESEARCH OUTLINES, AND THESIS OUTLINE…... ...................................................................................................................17 3.1. Research Gaps in Existing Body of Literature ..................................................17 3.2. Research Objectives...........................................................................................18 3.3. Thesis Outline....................................................................................................20 CHAPTER 4. BACKGROUND .......................................................................................22 4.1. CCGA and CBGA Electronic Packages ............................................................22 4.2. CCGA Test Vehicle Description .......................................................................25 4.3. Solder Material Behavior and Fatigue...............................................................26 4.4. Cumulative Damage Prediction: Miner’s Rule..................................................37 4.5. Laser Moire Interferometry................................................................................39 4.6. Vibration Theory................................................................................................42 4.7. Chapter Summary ..............................................................................................52 CHAPTER 5. UNIFIED FINITE ELEMENT MODELING METHODOLOGY FOR PREDICTION OF SOLDER JOINT RELIABILITY UNDER THERMAL, POWER, AND VIBRATION ENVIRONMENTS FOR CERAMIC AREA ARRAY ELECTRONIC PACKAGES.............................................................................................53 5.1. Introduction........................................................................................................53 5.2. Unified Finite Element Modeling methodology................................................53 5.3. Chapter Summary ..............................................................................................70 vi CHAPTER 6. VALIDATION OF UNIFIED FEM FOR THERMAL CYCLING AND POWER CYCLING ENVIRONMENTS ..........................................................................72 6.1. Introduction........................................................................................................72 6.2. Laser Moire Interferometry................................................................................72 6.3. Accelerated Thermal Cycling Verification with Laser Moire Interferometry...88 6.4. Importance of including creep in every solder joint of FEM.............................91 6.5. Power Cycling PC Verification .........................................................................92 6.6. Chapter Summary ..............................................................................................94 CHAPTER 7. PREDICTIVE FATIGUE LIFE UNDER THERMAL CYCLING AND POWER CYCLING ENVIRONMENTS ..........................................................................95 7.1. Introduction........................................................................................................95 7.2. CBGA: 63Sn37Pb solder joint fatige life ..........................................................95 7.3. CCGA: 90Pb10Sn solder Joint fatige life........................................................101 7.4. Chapter Summary ............................................................................................105 CHAPTER 8. VALIDATION OF UNIFIED FEM AND DEVELOPMENT OF FATIGUE LIFE MODEL FOR VIBRATION................................................................106 8.1. Vibration Experimental Setup and Results......................................................106 8.2. FEM Modal Analysis and Stress Distribution.................................................110 8.3. Dye-and-Pry Analysis of Test Vehicle D: Solder Joint Failure Location .......112 8.4. Solder Joint Failure Mechanism and Microstructural Analysis.......................115 8.5. Fatigue Life Prediction for 90Pb10Sn Solder Under Vibration Loading ........118 8.6. Validation of Predictive Models......................................................................123 8.7. Discussion on Validation.................................................................................128 8.8. Chapter Summary ............................................................................................128 CHAPTER 9. DEVELOPMENT OF UNIVERSAL PREDICTIVE FATIGUE LIFE EQUATION AND STUDY OF THE EFFECT OF DESIGN PARAMETERS .............130 9.1. Introduction......................................................................................................130 9.2. Method.............................................................................................................131 9.3. Discussion of the Predictor Variables..............................................................142