Microwave Characterization of Copper-Clad Dielectric Laminate Substrates

Microwave measurement methods necessary to characterize copper-clad dielectric laminate substrates are reviewed to realize more precise design of planar circuits: that is, the balanced-type circular disk resonator method for the relative complex permittivity in the normal direction e rn and tan δ n , the cavity resonator method and the cut-off waveguide method for one in the tangential direction e rt and tan δ t , and the dielectric resonator method for the surface and interface conductivity of copper foil σ s and σ ι . The measured results of the frequency and temperature dependences of these parameters are presented for a PTFE substrate and a copper-clad glass cloth PTFE laminate substrate.