Modularized & parametric modeling methodology.

Transcription

1 Modularized & parametric modeling methodology. Active Device Passive Device Vias Foot print Lid Wall floor PWB Ceramic Taxonomy Technique Mechanical Component Library Analysis model Thermal Structural Vibration Divided-Conquer Algorithm Substrate Modeling Interface with E/CAD Laminated Structure Failure Mechanism Expert System Analysis Type Graph Theory Assembly Connect. Type Element Node Coupling SMT PTH Flip-Chip TAB WB Linear Global Analysis FEA Stress Concen. Natural Freq. Hot Spot FEA Formula Material Database Geometry & Process Variation Database Epoxy (thermal, mechanical) Solder Alloy Metals Solder Shape Lead shape Geometry profile Linear/Nonlinear Local Analysis Reliable. Predict. Parametric Study Optimization

2 Concurrent Thermo-mechanical design. Electric Design Electric Component Library Elect. Functional Design Process Selection & Location Elect. Acceptance Testing Optimization t Mechanical Design Mech. Behavior Design Process Mech. Acceptance Testing Mechanical Model-Primitive Library Selection & Location

3 Summary MP/FEM has been developed. Piece-wised component model are generated from mechanical component library. Several algorithm and techniques have been integrated into conventional FEM to automate modeling process. Enable concurrent modeling and analysis. MP/FEM has been applied to DCA modeling. One improved DCA structure is being under reliability test.

4 Divided - Conquer Algorithm for Multi-layered Board Modeling Printed Wiring Board Real Model Cut Section Reduced Model Z X Y

5 Packaging hierarchy and interconnection technologies chip-level 1st-level 2nd-level Wire Bonding TAB Flip-Chip BGA SMT PWB MCM SCM

6 MP/FEM Modeling of DCA 2D Model and Analysis Coupled field analysis model. Fillet symmetry. Fillet profile. PWB and chip thickness Gap height. Chip size. Number of Chips. Initial Warpage. Solder location. 3D Model and Analysis Chip size. Solder joint size. Chip location. Number of solder joints. Fillet profile. PWB and chip thickness. gap height.

7 MP/FEM modeling of Direct Chip Attach (DCA) Design for a reliable DCA assembly. Develop a correlation between DCA reliability data to FEM modeling. Sensitivity study of geometrical and dimensional parameters, and material properties. Encapsulant Fillet Chip Encapsulant Underfill Solder Joint PWB Half Model.

8 MP/FEM Modeling of DCA ( Structural Configuration ) No-Fillet 1 MX.260E E E E Non-Symmetric Fillets Multi-Chip ( different site)

9 MP/FEM modeling of DCA ( Board Initial Condition ) Flat MN MX.267E E E Warped-Down Warped-Up

10 Strain Plot on Encapsulant Small chip with 3 solder balls PLOT NO. 3 NODAL SOLUTION STEP=1 SUB =1 TIME=1 EPELZ (AVG) TOP RSYS=0 DMX = SMN = SMX = E E E E E E E E E E E Large Chip with 5 solder balls PLOT NO. 3 NODAL SOLUTION STEP=1 SUB =1 TIME=1 EPELZ (AVG) TOP RSYS=0 DMX =1.448 SMN = SMX = E E E E E E E E E E E

11 MP/FEM 3D Modeling of DCA with 3 Solder Balls Chip 1 5 Solder Balls 2 4 Encapsulant 3 PWB Entire Assembled FE Model

12 Multi-Level Analysis Model include very complex geometry and many tiny parts. Detail results for entire product model is impossible and unnecessary. From coarse evaluation to detail calculation. Not only zoom-in physically, but also may change geometry, analysis type and method. Global Prediction Hot point Stress distribution Warpage Local Analysis Stress location Trouble spot Detail Calculation MAx. strain Behavior Reliability

13 Mechanical Model Creation ( Parametric language and component library )

14 Taxonomic Technique ( a ) ( b ) Through via buried via ( c ) Blind via Rectangle Staggered Inverted Triangle Teardrops ( d ) MCM SCM DCA BGA PIH Flip-Chip ( e )

15 Modularized & Parametric Finite Element Methodology (Continued) The following techniques are integrated into Conventional FEA: Taxonomic Technique - Mechanical component library. Feature-based parametric language One-to-many modeling. Divide-and-conquer algorithm - PWB or substrate detail layout modeling. Global/local analysis - Zoom in analysis capability. Graph theory - Component to product assembly. Database and tool integration - Material database and user interface. Object oriented concept - Component model encapsulation and hierarchy.

16 Modularized & Parametric Finite Element Methodology ( MP/FEM - Introduction ) Why every new analysis start from scratch? There should be catalogs of model primitives, as there are catalogs of VLSI devices. MP/FEM originated from the observations: Limited number of components to fabricate a product. Limited types of interconnections in component assembly. Product design from a electrical component library. Advantage of MP/FEM: Provide concurrent capability. Fast model creation, and easy model modification. Reduce modeling repetitive. Integrated analysis capability.

17 Thermomechanical Design Current Status: Only at final stage of design process. Repetitive in nature, and always from scratch. Isolated model. Done by expert. Time consuming. Future Needs: Concurrent design. Correct-by-design. Handy tools for electrical designer. Comprehensive model. Rapid overturns.

18 Modularized & Parametric Modeling Methodology for Concurrent Design, Analysis, and Simulation Wen Zhou and Robert Fulton March 26, 1995 School of Mechanical Engineering, and Manufacturing Research Center Georgia Institute of Technology Atlanta, Georgia