A kind of mems microphone structure and manufacturing method thereof

Abstract

The invention discloses an MEMS (micro-electromechanical system) microphone structure, which comprises a substrate, a first dielectric layer, a lower electrode structure, an upper electrode structure and a discharging hole, wherein the substrate is provided with a cavity, the first dielectric layer is formed on the upper surface of the substrate, and is provided with a through hole which is communicated with the cavity, the lower electrode structure comprises a lower electrode main body part and a first leading-out part, the lower electrode main body part is mutually connected with the first leading-out part, the lower electrode main body part is positioned above the through hole, the first leading-out part is in contact with the upper surface of the first dielectric layer, the upper electrode structure comprises an upper electrode main body part, a second leading-out part and an opening ring support structure, the opening ring support structure is connected with the upper electrode main body part and the second leading-out part and is positioned in the area outside the lower electrode structure, the bottom of the opening ring support structure is supported on the substrate, an air gap is formed between the upper electrode main body part and the lower electrode main body part, and the discharging hole is formed in the upper electrode main body part or the lower electrode main body part and is communicated with the air gap. The MEMS microphone structure can avoid the damage or falling of an upper electrode and a diaphragm in the discharging process.

Description

technical field [0001] The invention relates to the technical field of micro-electro-mechanical systems, in particular to a MEMS microphone structure and a manufacturing method thereof. Background technique [0002] Microphones are divided into dynamic microphones and condenser microphones. The traditional dynamic microphone consists of a coil, a diaphragm and a permanent magnet. It is based on the principle that the movement of the coil in a magnetic field generates an induced current; while the main structure of a capacitive microphone is two capacitive plates, namely the diaphragm (Diaphragm ) and the backplate (Backplate), its working principle is that the sound pressure causes the deformation of the diaphragm, resulting in a change in the capacitance value, which is converted into an electrical signal output. [0003] MEMS microphones are by far one of the most successful MEMS products. MEMS microphone is a microphone manufactured by surface processing or bulk silicon...

AI Technical Summary

Problems solved by technology

But in this way, it is also easy to short-circuit the upper electrode and the lower electrode, resulting in the failure of the microphone

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