计及边缘效应的非平行梳状驱动器的静电力计算

Computation of electrostatic forces with edge effects for non-parallel comb-actuators

为准确计算梳状驱动器的静电力,针对非平行静电梳状驱动方式以及实际静电致动微机械器件电容边缘效应不可忽略的特点,进一步推导出忽略边缘效应的非平行静电梳状驱动器静电力计算式,并给出计及边缘效应的梳状驱动器以及非平行梳状驱动器静电力计算公式。采用有限元方法的三维仿真结果表明,对于不满足平行板电容器简化计算条件的模型,计及边缘效应的计算式具有更好的准确性。

The formulas for the capacitance and electrostatic force in a nonparallel combdrive actuator were derived to accurately predict the electrostatic force. In actual electrostatically actuated microelectromechanical devices, the capacitance edge effects are very significant, which greatly alter the electrostatic force. Therefore, the equations for the electrostatic force include the edgeeffect for parallel and nonparallel combdrives. The equations compare well with the results of a 3D finite element method simulation. Therefore, the equations including the edgeeffects can be used when parallel capacitor models are not sufficiently accurate.