Double-purpose thin film equipment for sound transmission and extension and manufacturing method thereof

Abstract

The invention relates to double-purpose thin film equipment for sound transmission and extension, comprising a piezoelectric electret thin film and a circuit board assembly; the piezoelectric electret thin film includes a porous polymer thin film, electrodes symmetrically installed at the two sides of the porous polymer thin film, and a thin film connection end electrically connected with the electrodes; positive and negative charges are respectively deposited on the upper and lower surfaces of a hole on the porous polymer thin film; and a first connection end electrically connected with the thin film connection end and a second connection end connected with an external circuit are installed on the circuit board assembly. The positive and negative charges are deposited on the upper and lower surfaces of the hole on the porous polymer thin film so as to form an electric dipole; under the influence of the pressure of sound wave, the thickness of the hole on the piezoelectric film changes, such that the size of the electric dipole in the hole changes, and compensation charges in the electrodes also change; therefore, the voltage between the electrodes changes, namely acoustoelectric conversion is realized by using a piezoelectric effect; and vice versa, the thickness of the piezoelectric film vibrates according to a reciprocal piezoelectric effect, the sound wave is generated, and the electroacoustic conversion is realized.

Description

【Technical field】 [0001] The invention relates to the field of microphone loudspeakers, in particular to a dual-purpose thin-film device for sound transmission and loudspeaker and a manufacturing method thereof. 【Background technique】 [0002] The current microphones mainly include the traditional electret condenser microphone (ECM) and the silicon microphone (also known as microelectromechanical system (MEMS) microphone) developed in recent years. The electret condenser microphone is composed of a single-sided metal-plated electret film and a metal electrode (back pole) with several small holes. The electret face is opposite the back electrode with a tiny air gap in between, which forms a capacitor. Due to the polarized charge on the electret, there is a potential difference between the two poles of the capacitor. When the sound wave acts on the electret film, the vibration of the diaphragm produces displacement and changes the capacitance of the capacitor, so that the ou...

AI Technical Summary

Problems solved by technology

[0004] The structure of traditional microphones and loudspeakers is relatively complex, including multiple parts, and the volume is relatively large. The parts need to be precisely processed, and the process requirements are very strict.

However, the cost performance of the newly developed silicon microphone needs to be improved, and the packaging process and quality problems need to be improved urgently.

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