CN203368748U

CN203368748U - Mems microphone

Info

Publication number: CN203368748U
Application number: CN 201320337018
Authority: CN
Inventors: 孟珍奎
Original assignee: AAC Acoustic Technologies Shenzhen Co Ltd
Current assignee: AAC Technologies Pte Ltd
Priority date: 2013-06-13
Filing date: 2013-06-13
Publication date: 2013-12-25
Anticipated expiration: 2023-06-13

Abstract

The utility model discloses an MEMS microphone comprsing an MEMS chip and an ASIC chip. The MEMS chip is electrically connected with the ASIC chip. The MEMS chip is provided with a first vibrating diaphragm, a second vibrating diaphragm and a backboard which is arranged between the first vibrating diaphragm and the second vibrating diaphragm. The first vibrating diaphragm and the second vibrating diaphragm are respectively arranged with the backboard in a spacing way so that a capacitor structure is formed. The position, which is right towards the first vibrating diaphragm and the second vibrating diaphragm, of the backboard is provided with multiple backboard through holes. The position, which is right towards the backboard, of the first vibrating diaphragm, is provided with multiple vibrating diaphragm through holes. The ASIC chip provides a bias voltage for the first vibrating diaphragm or the second vibrating diaphragm to work. The MEMS microphone has both high sensitivity and a high sound pressure level simultaneously.

Description

The MEMS microphone

[technical field]

The utility model relates to the microphone field, specifically a kind of MEMS microphone.

[background technology]

Development along with wireless telecommunications, Global Mobile Phone Users is more and more, the user not only is satisfied with conversation to the requirement of mobile phone, and want to provide high-quality communication effect, especially at present the development of Technology of Mobile Multimedia, the speech quality of mobile phone becomes more important, and the microphone of mobile phone is as the voice pick device of mobile phone, and the quality of its performance directly affects speech quality.

What application was more at present is the MEMS microphone, in order to reach superior voice pickup capacity, require the MEMS microphone to possess higher sensitivity and higher sound pressure level simultaneously, but the problem of facing now is that raising sensitivity and raising sound pressure level are contradiction for same diaphragm structure, improve sensitivity and will sacrifice sound pressure level, improve sound pressure level and will sacrifice sensitivity.How to solve and realize that the MEMS microphone possesses high sensitivity and high sound pressure level has become the focus that this area is studied simultaneously.

[utility model content]

The utility model provides a kind of MEMS microphone, and described MEMS microphone possesses high sensitivity and high sound pressure level simultaneously.

The purpose of this utility model is achieved in that

A kind of MEMS microphone, it comprises MEMS chip and asic chip, described MEMS chip and asic chip are electrically connected to, described MEMS chip is provided with the first vibrating diaphragm, the second vibrating diaphragm and backboard, described backboard is arranged between the first vibrating diaphragm and the second vibrating diaphragm, described the first vibrating diaphragm and the second vibrating diaphragm respectively with the spaced formation capacitance structure of described backboard, described backboard itself and described the first vibrating diaphragm and the second vibrating diaphragm over against position on be provided with some backboard through holes, described the first vibrating diaphragm itself and described backboard over against position on be provided with some vibrating diaphragm through holes, described asic chip provides bias voltage to the first vibrating diaphragm or the second vibrating diaphragm work.

Preferably, described MEMS chip further comprises the first pedestal and the second pedestal, described the first pedestal is provided with first operatic tunes relative with the first vibrating diaphragm, described the second pedestal is provided with second operatic tunes relative with the second vibrating diaphragm, between described the first pedestal and the first vibrating diaphragm, between the second pedestal and the second vibrating diaphragm, between the first vibrating diaphragm and backboard and be equipped with insulating barrier between the second vibrating diaphragm and backboard.

Preferably, also be provided with the projection that prevents the first vibrating diaphragm and the second vibrating diaphragm and backboard laminating adhesion on described backboard.

Preferably, to be even circumferential symmetrical for the some vibrating diaphragm through holes on described the first vibrating diaphragm.

The utility model has the advantage of: the MEMS microphone that the utility model provides possesses high sensitivity and high sound pressure level simultaneously.

[accompanying drawing explanation]

The schematic cross-section of the MEMS chip of the MEMS microphone that Fig. 1 provides for the utility model;

The vertical view of the MEMS chip of the MEMS microphone that Fig. 2 provides for the utility model;

The upward view of the MEMS chip of the MEMS microphone that Fig. 3 provides for the utility model.

[embodiment]

Below in conjunction with accompanying drawing, the utility model is elaborated.

MEMS microphone (the Micro-Electro-Mechanical-System Microphone that the utility model provides, MEMS condenser microphone) comprise MEMS chip and ASIC(Application Specific IC, application-specific integrated circuit (ASIC)) chip (not shown), described MEMS chip and asic chip are electrically connected to.

The MEMS chip 1 of the MEMS microphone provided for the utility model as shown in Figure 1 to Figure 3, described MEMS chip 1 is provided with the first vibrating diaphragm 21, the second vibrating diaphragm 22 and backboard 30, described backboard 30 is arranged between the first vibrating diaphragm 21 and the second vibrating diaphragm 22, described the first vibrating diaphragm 21 and the second vibrating diaphragm 22 respectively with the spaced formation capacitance structure of described backboard 30.Described the first vibrating diaphragm 21, the second vibrating diaphragm 22 and backboard 30 can adopt polysilicon or the conductive doped material of monocrystalline silicon to make.

Described backboard 30 is provided with the projection 32 that prevents the first vibrating diaphragm 21 and the second vibrating diaphragm 22 and backboard 30 laminating adhesions, described backboard 30 itself and described the first vibrating diaphragm 21 and the second vibrating diaphragm 22 over against position on be provided with some backboard through holes 31.

Described the first vibrating diaphragm 21 itself and described backboard 30 over against position on be provided with some vibrating diaphragm through holes 210, it is symmetrical that the some vibrating diaphragm through holes 210 on described the first vibrating diaphragm 21 are even circumferential.Some vibrating diaphragm through holes 210 on described the first vibrating diaphragm 21 can be regulated the vibrating diaphragm damping, discharge vibrating diaphragm stress, the air pressure of outer chamber in all right balance.

Described MEMS chip 1 has further comprised the first pedestal 11 and the second pedestal 12, described the first pedestal 11 is provided with first operatic tunes 110 relative with the first vibrating diaphragm 21, described the second pedestal 12 is provided with second operatic tunes 120 relative with the second vibrating diaphragm 22, and described the first pedestal 11 and the second pedestal 12 can adopt silica-base material to make.Described MEMS chip 1 is between described the first pedestal 11 and the first vibrating diaphragm 21, between the second pedestal 12 and the second vibrating diaphragm 22, between the first vibrating diaphragm 21 and backboard 30 and be equipped with insulating barrier 40 between the second vibrating diaphragm 22 and backboard 30, and described insulating barrier 40 can adopt the semiconducting insulation material to make.

The first vibrating diaphragm 21 of MEMS chip 1 of the present utility model can be optimized raising sensitivity, and the second vibrating diaphragm 22 can be optimized the raising sound pressure level.When needs are realized high sensitivity, asic chip output offset voltage is given the first vibrating diaphragm 21 work; When asic chip reception voice signal is judged as high sound pressure level, asic chip output offset voltage is given the second vibrating diaphragm 22 work; When asic chip output offset voltage works to the first vibrating diaphragm 21 and the second vibrating diaphragm 22 simultaneously, thereby the first vibrating diaphragm 21 has made up problem optimization of the second vibrating diaphragm 22 insufficient sensitivity has improved whole sensitivity, thereby having made up the inadequate problem optimization of the first vibrating diaphragm 21 sound pressure levels, the second vibrating diaphragm 22 improved whole sound pressure level.The MEMS microphone that the utility model provides possesses high sensitivity and high sound pressure level simultaneously, and the manufacture craft of MEMS chip is simple, cost is low, be easy to mass production, can not increase whole physical dimension because of improving performance simultaneously.

The foregoing is only better embodiment of the present utility model; protection range of the present utility model is not limited with above-mentioned execution mode; in every case the equivalence that those of ordinary skills do according to the utility model institute disclosure is modified or is changed, and all should include in the protection range of putting down in writing in claims.

Claims

1. a MEMS microphone, it comprises MEMS chip and asic chip, described MEMS chip and asic chip are electrically connected to, it is characterized in that: described MEMS chip is provided with the first vibrating diaphragm, the second vibrating diaphragm and backboard, described backboard is arranged between the first vibrating diaphragm and the second vibrating diaphragm, described the first vibrating diaphragm and the second vibrating diaphragm respectively with the spaced formation capacitance structure of described backboard, described backboard itself and described the first vibrating diaphragm and the second vibrating diaphragm over against position on be provided with some backboard through holes, described the first vibrating diaphragm itself and described backboard over against position on be provided with some vibrating diaphragm through holes, described asic chip provides bias voltage to the first vibrating diaphragm or the second vibrating diaphragm work.

2. MEMS microphone according to claim 1, it is characterized in that: described MEMS chip further comprises the first pedestal and the second pedestal, described the first pedestal is provided with first operatic tunes relative with the first vibrating diaphragm, described the second pedestal is provided with second operatic tunes relative with the second vibrating diaphragm, between described the first pedestal and the first vibrating diaphragm, between the second pedestal and the second vibrating diaphragm, between the first vibrating diaphragm and backboard and be equipped with insulating barrier between the second vibrating diaphragm and backboard.

3. MEMS microphone according to claim 1, is characterized in that: also be provided with the projection that prevents the first vibrating diaphragm and the second vibrating diaphragm and backboard laminating adhesion on described backboard.

4. MEMS microphone according to claim 1, it is characterized in that: it is symmetrical that the some vibrating diaphragm through holes on described the first vibrating diaphragm are even circumferential.