A ground shielded low loss transmission line using Au-to-Au thermo compressive packaging for RF applications

A ground-shielded transmission line consisting of the suspended signal line and the upper and bottom Au-to-Au packaged ground plates was designed, manufactured and tested. The simulation results indicated that the fully ground-shielded scheme could effectively reduce the signal loss resulted from dielectric coupling loss and radiation loss. The fabricated ground-shielded signal line has demonstrated low transmission loss of 0.37dB/mm up to 50GHz in our experiments, which was less than 0.68dB/mm of the conventional coplanar waveguide.