Characterization of layered transmission lines

The frequency characteristic of a transmission line consisting of a copper core, a passivation layer of nickel and a final gold plating is compared to technological alternatives. Due to the permeability of nickel the conductor shows high skin losses even for thin passivations (100 run). Based on the quasi TEM-approximation line parameters of layered transmission lines are determined. The surprising and unexpected result is, that transmission lines with an gold plating have higher ohmic losses and attenuation than lines with only a nickel passivation over a wide frequency range