This paper reports the performance improvement of micromachined piezoelectric microspeakers that are audible in open air according to the geometrical parameters. The sound pressure level (SPL) of the microspeaker fabricated with a piezoelectric ZnO film is even more enhanced due to the carefully designed process conditions and electrode shapes. The SPL of the fabricated microspeakers, which have a square electrode, shows more than 50 dB from 400 Hz to 20 kHz; the highest SPL is about 94 dB at 9.5 kHz with 5 V_pp sinusoidal input biases and 3 mm distances from the fabricated microspeakers to the reference microphone.

中文翻译：

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基于ZnO的微机械扬声器的几何效应

本文报告了根据几何参数在露天可听的微机械压电微型扬声器的性能改进。由于精心设计的工艺条件和电极形状，使用压电ZnO薄膜制成的微型扬声器的声压级（SPL）甚至更高。带有方形电极的微型扬声器的SPL在400 Hz至20 kHz范围内显示超过50 dB；在9.5 kHz时，最高SPL约为94 dB，正弦输入偏置为5 V _pp，从微型扬声器到参考麦克风的距离为3 mm。