Expert Series

What is Impedance and Dielectric Spectroscopy? (Intro)

Rosario A. Gerhardt

Abstract

In this tutorial, the technique of impedance and dielectric spectroscopy will be described in the simplest possible terms. It will begin by describing the expected responses for the real and imaginary impedance of a wide range of material and device types. Then the conversion to three other formalisms known as admittance, electric modulus and permittivity will be used to demonstrate the detailed information that is often hidden inside of the partially analyzed data. Examples will be provided that will help not only understand the physical processes that are happening inside of the material/device but also develop an understanding of how to control the outcome. Examples ranging from materials used in insulating layers in integrated circuits and packaging materials to highly conducting materials used in solar cells and batteries will be provided. It will be shown that it is possible to relate the spectra obtained to the presence of certain key responses: charge storage, electronic conduction, surface adsorption, switching phenomena and many others. Complementary techniques that are used to corroborate the physical assignments will also be included. The tutorial will end with examples that demonstrate that this technique is exceptionally good for establishing quality control in a production environment and/or to assess service life of electronic and non-electronic components in a non-destructive way.

Keywords: dielectric spectroscopy, impedance, ieee, ims, tutorials, education, rosario gerhardt

View the Full Video Tutorial

Presenter

Rosario A. Gerhardt

Georgia Institute of Technology

United States

Rosario A. Gerhardt

Biography

Dr. Rosario A. Gerhardt is Professor of Materials Science and Engineering at the Georgia Institute of Technology in Atlanta, Georgia, where she has been on the faculty since 1991. She was named Senior Goizueta Foundation Faculty Chair in 2015. Before coming to Georgia Tech, she worked at the Center for Ceramics Research at Rutgers- The State University of New Jersey for six years after receiving her doctoral degree from Columbia University.

Prof. Gerhardt’s research focuses on determining structure-property-processing relationships in a wide range of materials including metals, polymers, ceramics and their composites. She is the author or co-author of over 200 refereed research articles, five patents, and has edited five books. Her publications include research on the synthesis and fabrication of single-phase and composite materials and their electrical, optical and microstructural characterization. Her research aims to provide linkages between the underlying structure of the material and key responses that may be used for enhancing sample fabrication, electrical conductivity, charge storage, or for chemical sensing or mechanical degradation detection. Dr. Gerhardt’s research illustrates the importance of characterizing the microstructure of materials and devices at all length scales. Her research has been funded by the National Science Foundation, the U.S. Department of Energy, NASA and many industrial companies.

She currently serves on the Science Review Committee of the Spallation Neutron Source at ORNL and the Defense Materials, Manufacturing and Infrastructure Standing Committee at the National Academies. Prof. Gerhardt has been a member of The American Ceramic Society continuously since 1982. From 1996-2001, she served as an Executive Officer of the Electronics Division of ACerS. Dr. Gerhardt was elevated to ACerS Fellow in 2000.

Affiliation(s)

Georgia Institute of Technology

United States