The impact of moisture absorption on the electrical characteristics of organic dielectric materials

Abstract

Organic dielectric materials will absorb moisture when in direct contact with a liquid or a humid environment. The dielectric then becomes a two-phase dielectric composite with new dielectric characteristics. Using the Lichtenecker Equation, the composite dielectric permittivity and loss characteristics are modeled. The loss modeling includes the polymer dielectric loss characteristics, as well as the conductive loss of the moisture. The model is also used to predict the frequency dispersion of the relative permittivity at lower frequencies caused by the conductivity of the moisture. The modeling is validated using high frequency measurements of interdigital capacitors, which correspond to the modeling within 5% across the entire examined frequency range

A Modeling Approach for Predicting the Effects of Dielectric Moisture Absorption on the Electrical Performance of Passive Structures

“…This is designed to simulate moisture settled onto the dielectric interface between the encapsulation material and redistribution layer. Moisture conductivity is 0.25 S/m, which is what was observed in the measurements published in [16].…”

“…A summary of different composite dielectric modeling techniques was offered by the authors in [16]. Goncharenko et al [17] also gives an analysis of the state-of-the-art techniques for determining the effective permittivity when moisture is absorbed into a dielectric.…”

“…In a previous paper [16], the authors studied the effects of moisture absorption on the relative permittivity and loss tangent of polymers, a technique that will be further used in this paper. The main contributions of this paper are:…”

“…After that, a very brief summary of the effects of moisture absorption on polymers is given, as published in [16]. The next sections cover in-depth investigations on the impact of moisture on transmission lines and antennas.…”

“…(1) Moisture (parallel isotropic), (2) moisture and silicon, (3) moisture, silicon, and encapsulation, (4) moisture, silicon, encapsulation, and BCB. and s moisture ¼ 0.25 S/m because those were the values determined by the experimental validation described in the second and in more detail in[16]. These values are then known to be realistic.…”