6
ELECTRICAL PROPERTIES OF DIELECTRICS
6.1 Polarization of Dielectrics
6.1.1 Electronic Polarization
6.1.2 Orientational (Dipole) Polarization
6.1.3 Ionic (Molecular) Polarization
6.1.4 Relative Permittivity
6.2 Classification of Dielectric Materials
6.3 Frequency-Dependent Dielectric Behavior
6.3.1 DC Dielectric Losses
6.3.2 Frequency-Dependent Dielectric Model: Single Pole
6.3.3 Anomalous Dispersion
6.3.4 Frequency-Dependent Dielectric Model: Multipole
6.3.5 Infinite-Pole Model
6.4 Properties of a Physical Dielectric Model
6.4.1 Relationship Between ε′ and ε″
6.4.2 Mathematical Limits
6.5 Fiber-Weave Effect
6.5.1 Physical Structure of an FR4 Dielectric and Dielectric Constant Variation
6.5.2 Mitigation
6.5.3 Modeling the Fiber-Weave Effect
6.6 Environmental Variation in Dielectric Behavior
6.6.1 Environmental Effects on Transmission-Line Performance
6.6.2 Mitigation
6.6.3 Modeling the Effect of Relative Humidity on an FR4 Dielectric
6.7 Transmission-Line Parameters for Lossy Dielectrics and Realistic Conductors
6.7.1 Equivalent Circuit, Impedance, and Propagation Constant
6.7.2 Telegrapher’s Equations for Realistic Conductors and Lossy Dielectrics
References
Problems
As the speed of digital systems continues to increase with Moore’s law, the electrical performance of the dielectric layers of the printed circuit board, package, or multichip modules becomes significantly more important. Dielectric materials that worked perfectly well for slower designs become increasingly difficult ...
