We design and fabricate electrostatically actuated micro-speakers with circular diaphragms and peripheral electrode configuration. The novel electrode configuration mitigates the squeeze film damping and increases pull-in voltage when compared with the conventional parallel plate electrostatic transducer design. Finite element analysis shows that under dynamic conditions, we can achieve diaphragm deflections as much as 80 times the gap between the electrodes because of the proposed design. We compare the conventional design of electrostatically actuated audio speakers – where typical electrode separation gaps are around 60 to $100~{\mu }\text{m}$ and actuation voltages are in the range of 10 to 200 volts – with the proposed peripheral electrode design with an electrode separation gap of $1~ {\mu }\text{m}$ and actuation voltage ≤100 volts. The SPL obtained is comparable to the existing designs and ranges from 40 to 60 dB at 1 kHz at 1 cm with different sizes of the micro-speakers. The efficiency achieved with the proposed design is 100⁻⁴% at resonance which is at least two orders higher than the typically observed value for electrostatic micro-speakers. [2020-0134]

中文翻译：

---

具有外围静电驱动的新型 MEMS 扬声器

我们设计和制造带有圆形振膜和外围电极配置的静电驱动微型扬声器。与传统的平行板静电换能器设计相比，新型电极配置减轻了挤压膜阻尼并增加了引入电压。有限元分析表明，在动态条件下，由于所提出的设计，我们可以实现高达电极之间间隙的 80 倍的隔膜偏转。我们比较了静电驱动音频扬声器的传统设计——其中典型的电极分离间隙约为 60 到 $100~{\mu}\text{m}$ 和驱动电压在 10 到 200 伏的范围内 - 建议的外围电极设计具有电极分隔间隙 $1~ {\mu }\text{m}$ 和驱动电压≤100伏。获得的 SPL 与现有设计相当，并且在 1 kHz 和 1 cm 处具有 40 到 60 dB 的范围，具有不同尺寸的微型扬声器。所提出的设计实现的效率在共振时为 100 ^-4 %，这比静电微型扬声器的典型观察值高至少两个数量级。[2020-0134]