Optimized coplanar waveguides in membrane technology for wideband on-wafer calibrations

In this paper we present an optimized interconnect structure which allows for the accurate broadband characterization of coplanar waveguides (CPWs) built in membrane technology. For both the membrane CPW and the silicon part of the interconnect structure, we compare measurements against calculations, and, where available, also against full-wave simulations. The agreement for the membrane CPW part is very good over a frequency range of 110 GHz. In addition, we detect a tangible sensitivity of the broadband propagation characteristics to the relative permittivity of the membrane material for both parts of the interconnect structure.