A MEMS-based hybrid circuit having metallized cavity for Ku-band wireless communication

We present a hybrid circuit fabricated by means of MicroElectroMechanical System (MEMS) process technology. It has been newly developed as a component for the application to wireless communication system. The hybrid circuit consists of inductors and shunt capacitors, which have been fabricated on a silicon wafer. In our device, an etched 30 /spl mu/m deep cavity is utilized to minimize insertion losses of transmission lines for inductors. Moreover, the bottom of cavity is metallized for the ground biasing of shunt capacitors. Our metallized cavity structure and proposed fabrication process scheme for that have the advantages in terms of insertion loss issue and a variety of applicability in RF MEMS field. In S-parameter measurement, we obtained 2.03 dB and 2.18 dB as insertion losses and 21.63 dB as return loss at 12 GHz. The measured frequency characteristics are also well agreed with the simulation results.