Low-voltage small-size double-arm MEMS actuator

Abstract

The fabrication and characterisation of a double-arm cantilever-type metallic DC-contact MEMS actuator with low pull-down voltage are reported. Bi-layer TiW cantilevers with an internal stress gradient were fabricated using a microwave-compatible fabrication process. Owing to its small size, cantilever length (L=5–50 µm) and width (W=2–40 µm), i.e. ∼10–100 times smaller in lateral dimensions than a standard MEMS actuator, this actuator showed actuation voltages lower than 10 V. RF measurements of the 10 µm-wide actuators yielded an average insertion loss less than 1 dB and isolation higher than 40 dB up to 25 GHz. The developed actuator is well suited for integration in reconfigurable microwave circuits and systems such as reconfigurable antennas and arrays.