CN209017321U

CN209017321U - MEMS microphones and electronics

Info

Publication number: CN209017321U
Application number: CN201822179114.3U
Authority: CN
Inventors: 解士翔
Original assignee: Goertek Techology Co Ltd
Current assignee: Goertek Microelectronics Inc
Priority date: 2018-12-24
Filing date: 2018-12-24
Publication date: 2019-06-21
Anticipated expiration: 2028-12-24

Abstract

The utility model discloses a kind of MEMS microphone and electronic equipment, wherein the MEMS microphone includes the cover, substrate and MEMS chip, and the substrate and the cover are enclosed accommodating cavity, and offer the acoustic aperture being connected to the accommodating cavity；The MEMS chip includes substrate, vibrating diaphragm and backboard, and the substrate is connected to the substrate, and offers the through-hole being connected to the acoustic aperture, and the vibrating diaphragm and backboard are all connected to one end that the substrate deviates from the substrate；The cross-sectional area of the through-hole is in reduced trend along the backboard to the direction of the substrate.The acoustical quality of microphone can be improved in technical solutions of the utility model.

Description

MEMS microphone and electronic equipment

Technical field

The utility model relates to microphone techniques field, in particular to a kind of MEMS microphone and electronic equipment.

Background technique

MEMS microphone is using MEMS (Micro-Electro-Mechanical Systems, MEMS) technique The microphone of production.This microphone includes two chips: MEMS chip and specific integrated circuit (Application Specific Integrated Circuit, ASIC) chip, the envelope which forms in a substrate and shell In assembling structure, MEMS chip is set to the inside of printed circuit board, is provided with vibrating diaphragm on MEMS chip, is located at MEMS chip and base Cavity between on the inside of plate can be described as the ante-chamber of MEMS microphone, after remaining seal cavity then can be described as MEMS microphone Chamber.The frequency response curve of MEMS microphone is more straight, and acoustical quality is better, and the preceding cavity configuration of MEMS microphone and the frequency response of product Related, current preceding cavity configuration is not reasonable, and then influences product frequency response and sound quality.

Utility model content

The main purpose of the utility model is to provide a kind of MEMS microphone, it is intended to obtain the good microphone of acoustical quality.

To achieve the above object, the utility model proposes MEMS microphone include:

The cover；

Substrate, the substrate and the cover are enclosed accommodating cavity, and offer the acoustic aperture being connected to the accommodating cavity； And

MEMS chip, the MEMS chip include substrate, vibrating diaphragm and backboard, and the substrate is connected to the substrate, and opens Equipped with the through-hole being connected to the acoustic aperture, the vibrating diaphragm and backboard are all connected to one end that the substrate deviates from the substrate；

The cross-sectional area of the through-hole is in reduced trend along the backboard to the direction of the substrate.

Optionally, the through-hole hole is in circular cone shape.

Optionally, the angle that the inner wall of surface of the substrate towards the substrate and the through-hole is formed is θ, θ's Value range is more than or equal to 60 ° less than 90 °.

Optionally, diameter range of the through-hole close to one end of the substrate is to be less than or equal to more than or equal to 400 microns 800 microns.

Optionally, be formed with gap between the backboard and the vibrating diaphragm, the backboard offer the connection gap with The via hole of the accommodating cavity.

Optionally, the both ends of the backboard are connect with the substrate, and the middle part of the backboard is to the side for deviating from the substrate To bending, so as to form the gap between the backboard and the vibrating diaphragm.

Optionally, the MEMS microphone further includes asic chip, and the asic chip is set in the accommodating cavity, and with The substrate and MEMS chip electrical connection.

Optionally, the asic chip is set to the substrate, and the asic chip and the MEMS chip pass through metal wire Connection.

Optionally, the cover is connected with the substrate by conducting resinl or tin cream.

The utility model also proposes a kind of electronic equipment, including MEMS microphone as described above.

The MEMS microphone of technical solutions of the utility model includes being enclosed the cover of accommodating cavity with substrate and set on appearance Set intracavitary MEMS chip, MEMS chip include the substrate on substrate and be connected to substrate away from one end vibrating diaphragm of substrate and Backboard offers acoustic aperture on substrate, and substrate offers through-hole, and the space enclosed between substrate and substrate is MEMS microphone Ante-chamber, the shape of the ante-chamber influence the high frequency section of product, the cross-sectional area of through-hole on the direction of backboard to substrate are arranged For reduced trend, so that the operatic tunes opening close to acoustic aperture is small, the operatic tunes opening close to vibrating diaphragm is big, while making the volume of ante-chamber Becoming smaller, the shape and volume change of the ante-chamber can be such that the formant of MEMS microphone moves back, guarantee that frequency response curve becomes straight, To improve the acoustical quality of MEMS microphone.

Detailed description of the invention

In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment Or attached drawing needed to be used in the description of the prior art is briefly described, it should be apparent that, the accompanying drawings in the following description is only It is some embodiments of the utility model, for those of ordinary skill in the art, in the premise not made the creative labor Under, the structure that can also be shown according to these attached drawings obtains other attached drawings.

Fig. 1 is the longitudinal sectional drawing of one embodiment of the utility model MEMS microphone；

Fig. 2 is the longitudinal sectional drawing of MEMS chip in MEMS microphone shown in Fig. 1.

Drawing reference numeral explanation:

Label	Title	Label	Title
				100	MEMS microphone	511	Through-hole
10	The cover	53	Vibrating diaphragm
				10a	Accommodating cavity	55	Backboard
30	Substrate	551	Via hole
				31	Acoustic aperture	70	Asic chip
50	MEMS chip	90	Metal wire
				51	Substrate

The embodiments will be further described with reference to the accompanying drawings for the realization, functional characteristics and advantage of the utility model aim.

Specific embodiment

The following will be combined with the drawings in the embodiments of the present invention, carries out the technical scheme in the embodiment of the utility model Clearly and completely describing, it is clear that described embodiment is only a part of the embodiment of the utility model, rather than all Embodiment.Based on the embodiments of the present invention, those of ordinary skill in the art are not making creative work premise Under every other embodiment obtained, fall within the protection scope of the utility model.

It is to be appreciated that the directional instruction (such as up, down, left, right, before and after ...) of institute in the utility model embodiment It is only used for explaining in relative positional relationship, the motion conditions etc. under a certain particular pose (as shown in the picture) between each component, such as When the fruit particular pose changes, then directionality instruction also correspondingly changes correspondingly.

In the present invention unless specifically defined or limited otherwise, term " connection ", " fixation " etc. should do broad sense reason Solution, for example, " fixation " may be a fixed connection, may be a detachable connection, or integral；It can be mechanical connection, it can also To be electrical connection；It can be directly connected, the connection inside two elements can also be can be indirectly connected through an intermediary Or the interaction relationship of two elements, unless otherwise restricted clearly.It for the ordinary skill in the art, can be with The concrete meaning of above-mentioned term in the present invention is understood as the case may be.

In addition, the description for being such as related to " first ", " second " in the present invention is used for description purposes only, and cannot manage Solution is its relative importance of indication or suggestion or the quantity for implicitly indicating indicated technical characteristic.Define as a result, " the One ", the feature of " second " can explicitly or implicitly include at least one of the features.In addition, the skill between each embodiment Art scheme can be combined with each other, but must be based on can be realized by those of ordinary skill in the art, when technical solution It will be understood that the combination of this technical solution is not present in conjunction with there is conflicting or cannot achieve when, also not in the utility model It is required that protection scope within.

The utility model proposes a kind of MEMS microphones 100.

Referring to Fig.1 and 2, the MEMS microphone 100 includes the cover 10, substrate 30 in the utility model embodiment And MEMS chip 50；

The substrate 30 is enclosed accommodating cavity 10a with the cover 10, and offers and be connected to the accommodating cavity 10a Acoustic aperture 31；The MEMS chip 50 includes substrate 51, vibrating diaphragm 53 and backboard 55, and the substrate 51 is connected to the substrate 30, and The through-hole 511 being connected to the acoustic aperture 31 is offered, the vibrating diaphragm 53 and backboard 55 are all connected to the substrate 51 away from described One end of substrate 30；

The cross-sectional area of the through-hole 511 is in reduced trend along the backboard 55 to the direction of the substrate 30.

In the present embodiment, MEMS microphone 100 includes the cover 10, substrate 30 and MEMS chip 50, wherein substrate 30 is Pcb board, the pcb board can successively include top solder mask, copper foil layer, semi-solid preparation layer and buried capacitor layer from top to bottom, certainly, no The pcb board of same specification has the different numbers of plies, can be selected according to actual needs.The U-shaped setting of the cover 10,10 He of the cover Substrate 30 surrounds closed space, and MEMS chip 50 is set in the space.The shape in the space that the cover 10 and substrate 30 surround can To be cube or sphere, it is not limited thereto.

The metal shell that the cover 10 can be integrally formed or the non-metal shell coated with metal material, 10 He of the cover Substrate 30 surrounds accommodating cavity 10a, it is possible to understand that and ground, the cover 10 can be connected with the substrate 30 by conducting resinl or tin cream, Being electrically connected for the cover 10 and substrate 30 may be implemented, to form the shielding cavity of a conducting, external electromagnetic wave can be prevented Interference enhances the protective effect to internal MEMS chip 50, guarantees the conversion performance of MEMS chip 50.Certainly, the cover 10 and base It can also be connected to by other conductive materials between plate 30.

In order to realize the function that quiets down of MEMS microphone 100, acoustic aperture 31 is offered on substrate 30, facilitates the stream of voice signal Enter, MEMS chip 50 be used for perceive and detect from acoustic aperture 31 flow into voice signal, voice signal can be converted to electric signal into Row transmission.In addition, MEMS microphone 100 further includes asic chip 70, the asic chip 70 is set in the accommodating cavity 10a, And it is electrically connected respectively with the substrate 30 and MEMS chip 50.Asic chip 70 is used to provide voltage for MEMS chip 50, and right The signal that MEMS chip 50 exports carries out processing amplification, so that MEMS microphone 100 provides the function that quiets down for electronic equipment.

Wherein, MEMS chip 50 includes the substrate 51 set on the substrate 30, and the material of substrate 51 is generally monocrystalline silicon, more The materials such as crystal silicon or silicon nitride, the outer shape of substrate 51 are substantially in cube, can be connect by colloid with substrate 30.It should Substrate 51 is arranged around the periphery of acoustic aperture 31, and offers through-hole 511, which is connected to acoustic aperture 31, and the two cooperatively forms The operatic tunes cavity of MEMS microphone 100, it is ensured that the incoming smoothness of sound, and sound can be made along acoustic aperture 31 and through-hole 511 Peripheral wall is incoming in continuously curve, improves the sound quality of sound.Through-hole 511 herein is transversal along backboard 55 to the direction of substrate 30 Reduced trend is presented in face area, and the cross-sectional area of through-hole 511, which can be, to be gradually reduced, and stepped subtract is also possible to Small, i.e. the side wall of through-hole 511 can be even surface, be also possible to step surface.The cross section of through-hole 511 can be it is round can also be with It is rectangular.

Meanwhile substrate 51 connects vibrating diaphragm 53 and backboard 55, the backboard 55 and the vibration away from one end of the substrate 30 Gap is formed between film 53, the middle part of the backboard 55 offers the via hole 551 for being connected to the gap and accommodating cavity 10a.This When, the space set is enclosed between MEMS chip 50 and substrate 30 as the ante-chamber of MEMS microphone 100.Vibrating diaphragm 53 due to material property its It also is provided with said minuscule hole, after sound enters in ante-chamber, is entered in accommodating cavity 10a through vibrating diaphragm 53, gap and via hole 551, this When, the space between MEMS chip 50 and the cover 10 is the back cavity of MEMS microphone 100, and sound wave makes vibrating diaphragm 53 generate vibration, Gap is remained between vibrating diaphragm 53 and backboard 55 to form a plane-parallel capacitor, it, can be with when vibrating diaphragm 53 vibrates Change gap between the two, to change capacitor, and then generates electric signal, and be transmitted to asic chip 70 and handled, from And realize stable quiet down.

Specifically, the both ends of the backboard 55 are connect with the substrate 51, and the middle part of the backboard 55 is to away from the lining The direction at bottom 51 is bent, so as to form the gap between the backboard 55 and the vibrating diaphragm 53.The MEMS chip 50 of the structure Dorsulum 55 is structure as a whole, so that 50 overall structural strength of MEMS chip is high, and element is few, convenient for assembly.Meanwhile ASIC core Piece 70 is set to the substrate 30, and the asic chip 70 is connect with the MEMS chip 50 by metal wire 90.Asic chip 70 It can be mounted on substrate 30, can also be directly welded on substrate 30 by way of planting tin ball by Heraeus.Asic chip 70 also need to cover by shielding glue, which can be COB glue (Chip On Board).Asic chip 70 and MEMS core Piece 50 is connected to by metal wire 90, so that asic chip 70 can provide constant voltage, metal wire herein for MEMS chip 50 90 can be gold thread or copper wire.In addition, the outer surface of substrate 30 is provided with pad, it can be by MEMS microphone 100 and mainboard It is welded and fixed, and is electrically connected on motherboard circuit, to transfer data on product applied by MEMS microphone 100.

In technical scheme, MEMS chip 50 includes the substrate 51 on the substrate 30 and is connected to substrate 51 and deviates from One end vibrating diaphragm 53 of substrate 30 and backboard 55 offer acoustic aperture 31 on substrate 30, and substrate 51 offers through-hole 511, substrate 51 The space enclosed between substrate 30 is the ante-chamber of MEMS microphone 100, and the shape of the ante-chamber influences the high frequency section of product, The cross-sectional area of through-hole 511 is in reduced trend on backboard 55 to the direction of substrate 30, so that the operatic tunes close to acoustic aperture 31 is opened Mouth is small, and the operatic tunes opening close to vibrating diaphragm 53 is big, while the volume of ante-chamber is become smaller, and the variation of the shape and volume can make The formant of MEMS microphone 100 moves back, and guarantees that frequency response curve becomes straight, to improve the sound quality effect of MEMS microphone 100 Fruit.

Referring to figure 2., optionally, the through-hole 511 is in circular cone shape.

In the present embodiment, through-hole 511 is arranged in the frustum of a cone, then the circular in cross-section of through-hole 511, longitudal section be it is trapezoidal, Accordingly, the shape of acoustic aperture 31 is also possible to circle, to guarantee the incoming smoothness of sound.

Optionally, the angle that the inner wall of surface of the substrate 51 towards the substrate 30 and the through-hole 511 is formed For θ, the value range of θ is more than or equal to 60 ° less than 90 °.

In the present embodiment, when the folder that the inner wall on surface of the substrate 51 towards the substrate 30 and the through-hole 511 is in When angle is 90 °, the shape of through-hole 511 is cylindrical shape, so in order to reduce the volume of ante-chamber, through-hole 511 is close to acoustic aperture 31 It is open at one end tapered, so that the folder that the inner wall of surface of the substrate 51 towards the substrate 30 and the through-hole 511 is in Angle is gradually reduced, in order to balance the convenience of reduction and the processing of ante-chamber volume, surface of the substrate 51 towards the substrate 30 with The angular range that the inner wall of the through-hole 511 is in is set greater than equal to 60 ° less than 90 °, and the MEMS Mike of the structure Wind 100 can obviously be moved back by testing the formant that test obtains, and frequency response curve tends to be straight, to significantly improve high frequency Sound quality.

Optionally, diameter range of the through-hole 511 close to one end of the substrate 30 is to be less than more than or equal to 400 microns Equal to 800 microns.

In the present embodiment, opening diameter of the through-hole 511 close to 30 one end of substrate cannot be excessive, otherwise corresponding through-hole 511 It is open at one end bigger far from substrate 30, so that the volume of ante-chamber is excessive, the frequency response curve of MEMS microphone 100 is influenced, And opening diameter of the through-hole 511 close to 30 one end of substrate is also unsuitable too small, is otherwise unfavorable for processing, is also unfavorable for voice signal It receives and propagates, so through-hole 511 is set as being less than or equal to more than or equal to 400 microns close to one end diameter range of substrate 30 800 microns, thus while facilitating processing, also available more straight frequency response curve, so that MEMS microphone 100 Acoustical quality is good.The angle that the inner wall of the structure and surface of the substrate 51 towards the substrate 30 and the through-hole 511 is in Range structure combines, the further good MEMS microphone 100 of available acoustical quality.

The utility model also proposes a kind of electronic equipment, which includes MEMS microphone 100, the MEMS microphone 100 specific structure is referring to above-described embodiment, since this electronic equipment uses whole technical solutions of above-mentioned all embodiments, Therefore at least there are all beneficial effects brought by the technical solution of above-described embodiment, this is no longer going to repeat them.Wherein, electric Sub- equipment can be wearing electronic equipment, such as smartwatch or bracelet, be also possible to mobile terminal, for example, mobile phone or notes This computer etc., is not limited thereto.

The above is only the preferred embodiment of the present invention, and therefore it does not limit the scope of the patent of the utility model, It is all under the inventive concept of the utility model, equivalent structure made based on the specification and figures of the utility model becomes It changes, or directly/be used in other related technical areas indirectly and be included in the scope of patent protection of the utility model.

Claims

1. a MEMS microphone, is characterized in that, comprises:

cover;

a base plate, the base plate and the cover are enclosed to form an accommodating cavity, and a sound hole communicating with the accommodating cavity is opened; and

A MEMS chip, the MEMS chip includes a substrate, a diaphragm and a backplate, the substrate is connected to the substrate, and a through hole is opened to communicate with the acoustic hole, and the diaphragm and the backplate are both connected to an end of the substrate facing away from the substrate;

The cross-sectional area of the through hole in the direction from the backplane to the substrate tends to decrease.

2 . The MEMS microphone of claim 1 , wherein the through hole is in the shape of a truncated cone. 3 .

3 . The MEMS microphone according to claim 2 , wherein the angle formed between the surface of the substrate facing the substrate and the inner wall surface of the through hole is θ , and the value range of θ is greater than or equal to 60. 4 . ° is less than 90°.

4 . The MEMS microphone of claim 2 , wherein the diameter of one end of the through hole close to the substrate is greater than or equal to 400 micrometers and less than or equal to 800 micrometers. 5 .

5. The MEMS microphone according to any one of claims 1 to 4, wherein a gap is formed between the back plate and the vibrating membrane, and the back plate is provided with a connection between the gap and the accommodating the vias of the cavity.

6 . The MEMS microphone according to claim 5 , wherein both ends of the back plate are connected to the substrate, and the middle portion of the back plate is bent in a direction away from the substrate, so that the The gap is formed between the back plate and the diaphragm.

7 . The MEMS microphone of claim 5 , wherein the MEMS microphone further comprises an ASIC chip, the ASIC chip is disposed in the accommodating cavity and is electrically connected to the substrate and the MEMS chip. 8 .

8 . The MEMS microphone of claim 7 , wherein the ASIC chip is disposed on the substrate, and the ASIC chip and the MEMS chip are connected by metal wires. 9 .

9 . The MEMS microphone of claim 1 , wherein the cover and the substrate are connected by conductive glue or solder paste. 10 .

10. An electronic device, comprising the MEMS microphone according to any one of claims 1 to 9.