Analysis of microwave resonances in a wirebond transition between Conductor-Backed Coplanar Eaveguides (CBCPWs)

Microwave resonances in a wirebond transition between conductor-backed coplanar waveguides (CBCTWs) on two different substrates (alumina and silicon) are investigated by using on-wafer measurements and three-dimensional (M) electromagnetic (EM) simulations in the frequency range from 1 to 26.5 GHz. The simulated resonant frequencies are in good agreement with the measured ones. For the first time, we clearly identify cascaded resonance modes of wirebond transition structures with two different substrates, by the electric field distribution at the resonant frequencies. The transition between the CPW grounds of the two substrates act as a node separating the modes, and consequently forming both the mode of the entire structure and the cascade of two different resonant modes on two substrates.