"Electronic Composites"

  by Dr. Minoru Taya


The subject of “Electronic Composites” is old and new.  For electromagnetic properties (particularly dielectric constraint and electric conductivity) of electronic composites have been studied extensively since the time of James Maxwell in 19th century, while electronic composites are key materials for microelectronics that include computer packages, actuators, sensors and micro-electromechanical systems (MEMS), nano-electromechanical systems (NEMS) and BioMEMS.

The aim of this book is to provide readers with introductory knowledge of various models that can relate the parameters of nano-and microstructure of the constituent materials to the overall properties of the electronic composites.  The readers that the author wishes to reach are graduate students and engineers who are interested in and/or involved in designing microelectronic packages, actuators, sensors and MEMS/NEMS/BioMEMS.  For the designing of optimum micro-and nano-structures of electronic composites they need to work on modeling on electronic composites, and proceed processing of the composites.  This book provides a summary of such modeling.  The contents of this book are introductory in early chapters (1-3) and more comprehensive in later chapters (4-8).  To help readers who want to learn in–depth knowledge, the book provides a long list of references and also detailed appendices at the end.

The present author (1995) wrote a paper on “Micromechanics Modeling of Electronic Composites” and has been teaching “Electronic Composites” as a graduate course at the University of Washington since 1998, thus the contents of the book are originated from his lecture notes.  There are no textbooks on electronic composites presumably due to that electronic composites are strongly interdisciplinary, covering a wide variety of subjects.  The author was motivated to edit his lecture notes into this monograph book by including more recent subjects related to electronic composites.

The following is a brief statement of chapters 1-8.  Chapter 1 introduces definition of electronic composites and early study on them covering the 19th and 20th centuries.  Chapter 2 discusses various types of electronic composites that are used in current applications, electronic packaging and MEMS, BioMEMS, sensors and actuators, and also control of electromagnetic waves.  In chapter 3, the foundation of the basic equations that govern the physical behavior of electronic composites, ranging from thermo-mechanical to electromagnetic behavior.  Chapter 4 is a key chapter of the book, discussing in details modeling of electronic composites based on effective medium theory, which covers from rudimental theory of law of mixtures all the way to more rigorous Eshelby’s model on coupled behavior such as piezoelectricity.  Chapters 5 and 6 discuss resistor network model and percolation model, respectively, which are effective for the cases that cannot be modeled by the effective medium theory, providing a nano-structure/macro-behavior relation of electronic composites.  Chapter 7 discusses lamination model, which is simple but effective in estimating the overall behavior of electronic composites with laminated microstructure associated often with a number of modern microelectronics.  Chapter 7 includes design of piezoelectric actuators for bending mode, thermal stress analysis in a thin film on a substrate and electromagnetic wave propagation in laminated composites with two examples, switchable window and surface plasmon resonance.  In the final chapter (8) discussion is made on selective engineering problems, processing of electronic composites as readers may want to be familiar with the current processing route, ranging from lithography to deposition of organic films, followed by standard measurements of key thermo-physical properties and electronmigration.

In all chapters, both index with subscripts and symbolic notations are used.  The former is sometimes needed for readers to grasp exact relations in the governing equations while the latter provides readers with simple expression, yet leading to matrix formulation, most convenient form for numerical calculations.