Liquid Metal droplet Tunable RF MEMS inductor

Issam EL GMATI, Ridha Ghayoula


A new variable inductor has been simulated, manufactured and tested. The idea is based on changing the morphology of a galinstain droplet by electrostatic actuation. A drop of 200µm diameter is used and the applied voltage is limited to 100 V. We demonstrate a tunable inductor that simultaneously achieves wide tuning range of 400% with high inductance from 1.8nH to 9.1 nH with a measured quality factor of 26 at 2 GHz and the self-resonance frequency is 4 GHz. Their results were compared and conclude that simulation results matched well with measurement. Comparison between our work and other published show excellent perfor-mance.


Tunable inductor, radiofrequency, MEMS, droplet, Galinstain.

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