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Dielectric and Magnetic Properties of Printed Wiring Boards and Other Substrate Materials



James R. Baker-Jarvis, Billy F. Riddle, Michael D. Janezic


This is an overview of dielectric and magnetic material measurements on printed wiring board and substrate materials. The most commonly used methods are presented. We begin with an overview of pertinent properties of circuit-board and substrate materials. We overview cavity and dielectric resonators, reentrant cavity, full-sheet resonance, coaxial probe, stripline, and capacitive methods. The frequency range of applicability and typical uncertainties associated with the methods are summarized. It is found that the reentrant cavity is useful for both loss and dielectric constant determination for materials of thickness greater than one-half millimeter. It is concluded that the full-sheet resonance technique is useful for the determination of the real part of the permittivity of clad substrates, but not for the loss measurement. Dielectric resonator techniques achieve the greatest sensitivity for both permittivity and loss. However, many printed wiring board materials are too lossy to achieve a resonance. We also present measurements of many substrate materials.
Technical Note (NIST TN) - 1512
Report Number


dielectric, dielectric, full-sheet, loss factor, microwave, permittivity, printed-wiring, resonance, stripline


Baker-Jarvis, J. , Riddle, B. and Janezic, M. (1999), Dielectric and Magnetic Properties of Printed Wiring Boards and Other Substrate Materials, Technical Note (NIST TN), National Institute of Standards and Technology, Gaithersburg, MD (Accessed June 24, 2024)


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Created February 28, 1999, Updated October 12, 2021