RF MEMS switches for 3D-IC phased array antenna modules

This paper presents modeling, design, fabrication, and measurement of a novel shunt capacitive RF MEMS switch. The switches are processed on a polyimide substrate in an intermediate layer of a monolithically processed vertically interconnected 3D-IC phased array antenna module at X-band. The copper switches have a pull-down voltage of 12 V and life cycle of at least 10⁷ actuations. The switches demonstrated less than 0.2 dB insertion loss and 11.5 to 17.1 dB isolation at X-band. Measurement results confirmed that the distributed modeling of the MEMS switches presented here improved the design of parallel-configured RF MEMS switches in phase shifters.