Evaluation of a stacked-FET cell for high-frequency applications

This paper presents the design, electromagnetic simulation strategies and experimental characterisation of a two-stage stacked-FET cell in a 100 nm GaN on Si technology around 18.8 GHz, suited for Ka band satellite downlink applications. A good agreement is found between the electromagnetic simulations and the measured performance on the manufactured prototype, thus demonstrating that a successful voltage combining architecture can be obtained in the frequency range of interest with the selected topology, based on a symmetric fork-like connection between the transistors. This proves the effectiveness of an appropriate electromagnetic simulation set-up in correctly predicting the crosstalk, which typically affects this structure, leading to a correct stacking operation.