Wideband electrical characterization of multilayer low-loss dielectric materials

The objective of this thesis is to conduct research work on wideband characterization of the complex dielectric constant of low-loss dielectric materials used in multilayer structures. The materials include Pyralux®, a polymer, and Green Tape™, a low-temperature co-fireable tape ceramic (LTCC). The study is composed of three main tasks. First, the effects of operating temperature and relative humidity on the complex dielectric constant of these materials, at low frequencies, will be investigated. Next, the complex dielectric constant of these materials will be determined for high frequencies, under ambient conditions. Finally, lifetime tests will be performed in order to determine the effects of aging on the complex dielectric constant of these materials, at low frequencies.

Since experiments will be performed at both low and high frequencies, both capacitor and T-resonator microstrip structures will be used. Analysis of the low frequency environmental test results indicate that both the dielectric constant and the dissipation factor of the polymer increase with both temperature and relative humidity. The results for the tape ceramic indicate that the dielectric constant and dissipation factor increase with temperature, but decrease with rising humidity. The results of the high frequency testing are compared to earlier experimentation in order to evaluate several test structures and techniques. Results of the aging experiments indicate that both the dielectric constant and the dissipation factor of the polymer are increasing over time. Conversely, both the dielectric constant and the dissipation factor of the tape ceramic are decreasing over time.