1. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Area Array Packages Interconnect Design and Reliability Analysis

2. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging Hierarchy Wafer Chip COB First level package (MultiChip Module) Second level package (PCB or Card) First level package (Single chip module) Third level package (Mother board) Source: J. H. Lau

3. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Existing Analysis Approaches for Electronic Packages 2-D Plain Stress/Strain Approach [Lau, 1992; Jahsman, 1993; Mckeown, 1993; Barker, 1993] =>Less accurate and can not identify the most susceptible solder joint Analytical Approach [Borgessen, 1992] =>Can not handle complicated material/geometry configuration 3-D Sliced Finite Element Model [Nagarajand, 1993] =>Less accurate and can not simulate all the solder joints Full-Scaled 3-D Approach =>Incredibly CPU time consuming and less efficient Local/Global (namely, Micro/Macro) Approach: (1) Rule of Mixture, (2) Self-Consistent Method, (3) Homogenization Method, (4) Finite Element Approach (preferred Choice) Local/Global Finite Element Approach [Corbin, 1993; Ju, 1995] =>Much more efficient than Full-Scaled 3-D approach with appropriate accuracy.

4. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Solder Ball Solder Mask Die Attach Ball Pad Molding Compound Gold Wire FR-4 BT Eutectic Solder 90Pb/10Sn Ball C-4 Solder Joint Heat Sink Cap Die FR-4 Ceramic CBGA/Corbin’s Local Model PBGA/Ju’s Local Model Micro-Macro CBGA and PBGA Analysis Model FR-4 card BT module Module mid-plane Solder pad 60Sn/40Pb eutectic solder Card mid-plane Module mid-plane Copper pad Molybdenum pad Ceramic module FR-4 card Card mid-plane Card eutectic Solder fillet 90%Pb/10%Sn solder ball Module eutectic solder fillet

5. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. FR-4 card BT module Module mid-plane Solder pad 60Sn/40Pb eutectic solder Card mid-plane Module mid-plane Copper pad Molybdenum pad Ceramic module FR-4 card Card mid-plane Card eutectic Solder fillet 90%Pb/10%Sn solder ball Module eutectic solder fillet Existing and Proposed Local/Global Approach Ju’s Model Corbin’s Model Proposed Model

6. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. u ( x, y, z, t )  u 0 ( x, y, t )  z  x ( x, y, t ) v ( x, y, z, t )  v 0 ( x, y, t )  z  y ( x, y, t ) w ( x, y, z, t )  ( x, y, t )  M x  x   M xy  y  Q x  H  2 u o  t 2  I  2  x  t 2  M  x   M y  y  Q y  H  2 v o  t 2  I  2  y  t 2 N x  2   x 2  2 N  2   x  y  N y  2   y 2   Q x  x   Q y  y  q   0  2   t 2 where ( H, I )  o ( z  h/2 h/2 , z 2 ) dz ( Q x, Q y )  (  xz,  yz )  h/2 h/2  dz ( N x, N y, N xy )  (  x,  y,  )  h/2 h/2  dz ( M x, M y, M xy )  (  x,  y  h/2 h/2 ,  ) zdz M x  D 11 d  dx dM x dx  C 55  d  dx      0 or d 2  dx 2  d   1  C 55 q  0  is the so-called shear correction factor. M xy = M y =0, Q y =0. For one-dimensional and static problem Beam Subjected to a Lateral/Vertical Loading General form for 2-D Plate:

7. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Y Z X P F nL /2 nL /2(1  n ) L L mD o D o A, G,  Circular Solid Beam Thin-walled Round Pipe (Ref. Cowper, 1996) Equivalent Beam Approach Input from 3-D model: F, P, M,  a,  s

8. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. f  w 1 (1  P 0i P i ) 2 i  1 5       1/2  w 2 (1  M 0i M i ) 2 i  1 5       1/2  w 3 (1  F 0i F i ) 2 i  1 5       1/2 20 o C 100 o C Yes Last Trial ? No Regression AnalysisSetP =0.94 P, F =1.16 F, n, m CalculateL o Do, E Find the Effective Plastic Material Properties Evaluate the Objective Function Nonlinear Approximation 0.0100.0080.0060.0040.0020.000 0.0e+0 1.0e+3 2.0e+3 3.0e+3 Strain Stress (N/mm 2 ) 1  L/L 0  1.2 0  n   m 

9. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Equivalent Beam vs. 3-D Solder Ball

10. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Global Analysis of PBGA (36 Solder Balls) The Material Properties Used in the PBGA Package The Geometry Data Used in the PBGA Package(mm) Young’s Poisson CTE Modulus(Mpa) Ratio (ppm) Silicon Chip 130,000 0.28 2.62 BT 19,000 0.2 15 FR-4 18,200 0.19 16 Silicon Chip BT FR-4 9x8x0.36 (mm) 14x13x0.36 14x13x1.71 1/4 of PBGA Finite Element Model

11. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Equivalent Beam vs. Solid-3D Results for PBGA The Net Shear Displacements of The Solder by Equivalent Beam Approach The Net Shear Displacements of The Solder by Full 3-D Model The Error Norm in Percentage The CPU Time of Two Approaches (CRAY/Jadi, ABAQUS) 4.6676E-04(mm) 1.0285E-03 1.3238E-03 9.7547E-04 1.3291E-03 1.5178E-03 1.1339E-03 1.3191E-03 1.4588E-03 4.7427E-04(mm) 1.0689E-03 1.3700E-03 1.0383E-03 1.4247E-03 1.5821E-03 1.1445E-03 1.3385E-03 1.4768E-03 1.584% 3.77% 3.373% 6.050% 6.713% 4.064% 0.931% 1.457% 1.220% Full-Scaled Model Equivalent Method CPU Time (sec.) 81,074 6,740

12. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Strain/Energy concentration effect N o = C * (  W) n N f = C * (  eq ) n Initial Crack Predicted by Strain Energy Density No. of Cycles to Failure Predicted by Coffin-Manson Eutectic Solder Solid-3D Model

13. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Leadless Chip Carrier, Y. H. Pao PBGA, R.Darveaux 2.1 1.15 0.84 0.34 4,997 500227 48 (768) (2,592) (6,144) Mesh Density (14,520) 757 420 290 143 18.7 27.14 54.73 10.4 (14,520) (6,144) (2,592) (768) Mesh Density Reliability vs. Mesh Density

14. Electronic Packaging Lab. of NTHU 國立清華大學動機系電子構裝實驗室 Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Electronic Packaging/CAE Labs National Tsing Hua University. Conclusions An equivalent Beam Theory is Derived for Area Array Package Analysis A Mesh Density independent Method is developed for Coffin-Mason and Energy Density Based Reliability Theories The Local-Global Approach Accomplished in this Research has been adopted by Industry as a Design Methodology for Area Array Packages A Liquid Formation Methodology for is Developed for Solder Ball Reflow Shape Prediction The 2nd Reflow Process Could Significantly Increase the Reliability Life Cycle for Area Array Type Packages Pad Geometry is Very Important for Packages Reliability. Good Pad Design Could Reduce the Manufacturing Cost and Increase the Reliability of the Package Liquid Formation Methodology Studied in This Research Could Applied to any Kind of Formation Geometry/Boundary Constraint