Development of a high Q-factor GaAs flip chip varactor for ka-Band application

The design and modelling of state-of the-art varactor diodes involves many tradeoffs based upon the physical properties of the material systems, wafer fabrication tolerances, and details of the specific device structure. In this work, the results of a developmental effort based upon novel design topologies, which have produced a flip chip GaAs varactor having the highest Q and the lowest parasitic series resistance and reactance yet reported in the industry resulting in the unique capability of operating at frequencies as high as 35 GHz, are presented.