Integrated differential silicon capacitor microphone

Abstract

The invention provides an integrated differential silicon capacitor microphone employing two or four differential MEMS sensitive elements which are in parallel connection and share one sound cavity. The microphone comprises a housing and a substrate, which are combined together. Moreover, one of the housing and the substrate is provided with a sound incoming hole. The microphone also comprises the two or four differential MEMS sensitive elements which are matched with each other; an integrated circuit; and a sound cavity. The integrated circuit is used for the buffering / amplification and output of an electric signal which is formed by the conversion of a sound wave through the sound incoming hole, the sound cavity and the differential MEMS sensitive elements. The electrical arrangement and connection mode between the integrated circuit and the differential MEMS sensitive elements are in axial symmetry or mirror symmetry relation. Through the means provided by the invention, the microphone improves the linearity and the maximum sound pressure level.

Description

technical field [0001] The invention relates to an integrated differential silicon capacitor microphone and its packaging scheme. Background technique [0002] Micro-electro-mechanical (MEMS micro-electro-mechanical system) microphones or silicon microphones are widely used for sound collection of tablet electronic devices due to their small size and suitable for surface mount, such as: mobile phones, MP3, recorders and monitors Equipment, etc. In order to meet the growing material and cultural needs of the people, the volume, cost, signal-to-noise ratio and other indicators of silicon microphones are constantly being optimized and improved. In the relevant optimization technical solutions, there are many efforts to improve the signal-to-noise ratio index under the existing processing technology conditions by using multiple silicon microphone differential MEMS sensitive elements together. The MEMS sensitive structure is used to improve the technical indicators such as the ...

AI Technical Summary

Problems solved by technology

[0004] For the differential silicon capacitor microphone, obviously, because its MEMS sensitive element is generally divided into three layers, it will introduce more complex design concepts than the conventional silicon capacitor microphone's MEMS sensitive element which is generally divided into two layers (back electrode and diaphragm). Correspondingly, there will be some restrictions on cost, yield, and product versatility, so that the differential microphone should be significantly higher than the conventional microphone in terms of maximum sound pressure level, linearity and other technical indicators.

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