Zhang / Driel / Fan Mechanics of Microelectronics

2006
ISBN: 978-1-4020-4935-4
Verlag: Springer Netherland
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, Band 141, 584 Seiten, eBook

Reihe: Solid Mechanics and Its Applications

This book is written by leading experts with both profound knowledge and rich practical experience in advanced mechanics and the microelectronics industry essential for current and future development. It aims to provide the cutting edge knowledge and solutions for various mechanical related problems, in a systematic way. It contains important and detailed information about the state-of-the-art theories, methodologies, the way of working and real case studies.

Zielgruppe

Research

Autoren/Hrsg.

Zhang, G.Q.

Driel, W.D. van

Fan, X.J.

Inhaltsverzeichnis

Microelectronics technology Introduction A heart of silicon In a little black box Baseline CMOS Non-CMOS options Packaging Systems Conclusions References Nomenclature Reliability practices Introduction Reliability assessment Reliability statistics Acceleration factor models Failure mechanisms Conclusions References Exercises Thermal Management Introduction Heat transfer basics Thermal design of assemblies Thermal design for a SQFP Heatsink design choices Conclusions / final remarks References Introduction to Advanced Mechanics Introduction Stress and strain Failure criteria Fracture mechanics Finite element method References Exercises Thermo-Mechanics of Integrated Circuits and Packages Introduction IC Backend and packaging processes and testing Thermo-mechanics of IC backend processes Thermo-Mechanics of packaging processes Thermo-Mechanics of coupled IC backend and packaging processes Case studies References Exercises Characterization and Modeling of Moisture Behavior Introduction Moisture diffusion modeling Characterization of moisture diffusivity and saturation concentration Vapor pressure modeling Hygroscopic swelling characterization & modeling Single void Instability behavior Subjected to vapor pressure and thermal stress Interface strength characterization and modeling Case studies References Exercises Characterization and Modeling of Solder Joint Reliability Introduction Analytical-empirical prognosis of the reliability Thermo-mechanical characteristics of soft solders Data evaluation and LIFE-time estimation Case studies References Exercises Virtual thermo-mechanical prototyping Introduction The state-of-the-art of virtual prototyping Case studies Conclusions References Exercises Challenges and future perspectives Introduction Product and process inputs Tests and experiments Multi-scale mechanics Advanced simulation tools Multi-physics modeling Material and interface behavior Simulation-based optimization Conclusions

Leseproben

Chapter 7
CHARACTERIZATION AND MODELLING OF SOLDER JOINT RELIABILITY (p. 378)

R. Dudek
Fraunhofer Institute Zuverlassigkeit und Mikrointegration, Gustav-Meyer-A - llee 25, 13355
Berlin, Germany

Abstract: This chapter addresses finite-element analyses (FEA) of solder fatigue phenomena caused by low-cycle thermo-mechanical loading. To begin with, an introduction to board level solder joint fatigue, characteristic thermal loading situations, the effects of thermal mismatch and analytical lifetime estimates is provided. Subsequently, challenges to the FE-based methodologies are discussed, which are particularly related to the non-linear mechanical properties of soft solders. Material constitutive models and the implementation of time and temperature dependent behaviours of leaded and lead-free solders are described. d Fatigue-life prediction modelling focuses on the strength of materials approaches, i.e., creep strain-based relations or energy-based relations. An overview on several fatigue-life prediction models from the literature is additionally provided. The FE-based methodology is applied to board-level solder joint reliability assessments for several components. Its wide applicability is illustrated by the choice of different types of components ranging from large t ceramic surface mount to small flip-chip assemblies on different types of substrates. For some of the application cases, results of parametric studies are presented and comparisons between failure prediction and testing results are made.

Key words: Solder fatigue, Finite Element simulations, solder plasticity, solder creep, primary and secondary creep, reliability predictions, coffin manson, board level test validation.

1. INTRODUCTION

The computational design of reliable microsystems, electronic packages as well as their interconnects can minimize expensive prototype development and testing. Accordingly, finite element (FE-) modelling is widely used to perform parametric studies on the thermo-mechanical behaviour of components like e.g., silicon microstructures, plastic packages, chip size/wafer level packages, or flip chip assemblies.

From a mechanical point of view all these structures include constituents, which are subjected to different loading conditions. The theoretical analysis of stresses within these constituents induced by environmental conditions requires the characterization of loads and material properties, respectively, as well as the knowledge of the appropriate failure criteria. Figure 1 provides an overview on the characteristic tasks to be performed for those thermomechanical finite element analyses (FEA).