Multi-layer, Thin-film Repulsive-force Electrostatic Actuators for a 2-DoF Micro-mirror

Inhalt:
This paper reports a two degree-of-freedom micro-mirror system driven by 4 flexible, multi-layer, thin-film repulsive-force electrostatic actuators (RFAs, each 13 x 19.5 mm). We demonstrate a functional multi-layer (>2- layer) RFA: it uses 4 – 8 layers for increased stroke length, has stable actuation without pull-in, has a consistent electrode pattern on each layer for ease of fabrication, separates oppositely-polarized electrodes on each layer with a polyimide substrate to prevent intra-layer shorting, and orients like-polarized electrodes on adjacent layers to prevent inter-layer shorting. We use four 4-layer RFAs (in antagonistic pairs) to drive a micro-mirror system with 35 Hz bandwidth and 8.8º / 7.6º, stable, controllable rotations about 2-DoF at up to 2000 V.