Comb drive resonator

QuickField simulation example

Problem Type
Axisymmetric multiphysics problem of Electrostatics coupled to Stress analysis.

Geometry

Comb thickness L_z = 40 um.
Gap between fingers d = 2.5 um.

Given
Relative permittivity of air ε = 1,
Relative permittivity of dielectric ε = 10,
Potential difference ΔU = 40 V

Task
Find the attraction force and calculate displacement.

Solution
Geometry model features symmetry and only half of the comb was simulated.

Results
The attraction force is f = 2.4 uN.
Comb x-displacement is 7 nm.

Color map of electric field stress distribution and deformed shape of the comb (scaled 500 times).

• Video: Comb drive resonator
  
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