Electrostatic curved electrode actuator

• Consists of a laterally compliant cantilever beam and a fixed curved electrode
• Cantilever and fixed electrode suspended above a ground plane
• Fabricated by polysilicon surface micromachining techniques
• Large displacements parallel to the wafer surface
• High force generation
• Gap distance between electrodes is small near the clamped edge of the beam and increases with the position along the length of the beam
• Electrostatic force deforming the beam along the outline of the curved electrode is created when a voltage is applied across the gap
• Shape of the curved electrode can be easily adjusted by changing the mask design
• Electrical insulation is required to prevent a short circuit between the beam and the curved electrode
  

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Related reading

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