CN213847003U

CN213847003U - MEMS sensor chip, microphone and electronic device

Info

Publication number: CN213847003U
Application number: CN202023206702.5U
Authority: CN
Inventors: 邱冠勋; 刘松; 周宗燐
Original assignee: Goertek Microelectronics Inc
Current assignee: Goertek Microelectronics Inc
Priority date: 2020-12-25
Filing date: 2020-12-25
Publication date: 2021-07-30
Anticipated expiration: 2030-12-25
Also published as: WO2022135003A1

Abstract

The utility model discloses a MEMS sensor chip, microphone and electronic equipment. The MEMS sensor chip comprises a substrate, a sensing assembly and an annular protection layer, wherein the substrate is provided with a cavity, the sensing assembly comprises a first annular supporting layer, a second annular supporting layer, a vibrating diaphragm and a back plate with a through hole, the first annular supporting layer is arranged on the substrate, the first annular supporting layer, the back plate, the second annular supporting layer and the vibrating diaphragm are sequentially stacked in the direction departing from the substrate, the annular protection layer is arranged on the peripheral side of the sensing assembly, and the annular protection layer at least covers the first annular supporting layer and/or the second annular supporting layer. In this way, the reliability of the first and/or second annular supporting layers may be ensured or provided, thereby improving the performance and reliability of the microphone.

Description

MEMS sensor chip, microphone and electronic device

Technical Field

The utility model relates to a sensor technical field, in particular to MEMS sensor chip, microphone and electronic equipment.

Background

A Micro-Electro-Mechanical System (MEMS) microphone is an acoustic-electric transducer manufactured by Micro-machining (MEMS) technology, and is widely applied to electronic devices such as mobile phones, tablet computers, cameras, hearing aids, intelligent toys, monitoring devices and the like due to its characteristics of small volume, good frequency response, low noise and the like. The MEMS microphone mainly comprises a packaging shell and an MEMS sensor chip arranged in the packaging shell, so that a sound signal is converted into an electric signal through the MEMS sensor chip.

At present, a MEMS sensor chip generally includes a substrate and a sensing component disposed on the substrate, where the sensing component includes a vibrating diaphragm and a back plate disposed opposite to each other, and the vibrating diaphragm and the back plate form a flat capacitor structure. The vibrating diaphragm vibrates under the action of sound waves, so that the distance between the vibrating diaphragm and the back plate is changed, the capacitance of the plate capacitor is changed, and sound wave signals are converted into electric signals.

In the preparation process of the MEMS sensor chip, sacrificial layers (mostly oxide layers) are arranged between a sensing component and a substrate and between a vibrating diaphragm and a back plate of the sensing component, and then part of the sacrificial layers are corroded by corrosive liquids such as HF acid or BOE solution and the like to release the micro-motor structure; the remaining sacrificial layer typically serves as a support layer for the MEMS structure to support the sensing elements.

However, during the etching process, the sacrificial layer is easily etched and transited, so that the reliability of the supporting layer is low, and the reliability of the MEMS sensor chip and the microphone is low.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a MEMS sensor chip aims at solving current MEMS sensor chip preparation technology, the lower technical problem of reliability of micromotor structure's supporting layer.

In order to achieve the above object, the present invention provides a MEMS sensor chip, including:

a substrate having a cavity;

the induction assembly comprises a first annular supporting layer, a second annular supporting layer, a vibrating diaphragm and a back plate with a through hole, the first annular supporting layer is arranged on the substrate, the back plate is arranged on one side, away from the substrate, of the first annular supporting layer, the second annular supporting layer is arranged on one side, away from the substrate, of the back plate, and the vibrating diaphragm is arranged on one side, away from the substrate, of the second annular supporting layer; and

the annular protective layer is arranged on the peripheral side of the induction assembly and at least covers the first annular supporting layer and/or the second annular supporting layer.

Optionally, the annular protection layer sequentially covers the first annular supporting layer, the back plate, the second annular supporting layer, and the diaphragm.

Optionally, the annular protection layer is integrally connected to the diaphragm.

Optionally, the diaphragm includes an annular connection portion integrally connected to the annular protection layer, and a vibration portion disposed inside the annular connection portion, and the vibration portion and the annular connection portion are disposed at an interval.

Optionally, the diaphragm further includes an isolator, and the isolator is at least partially disposed in a space between the vibrating portion and the annular connecting portion.

Optionally, the annular protective layer is an insulating protective layer.

Optionally, the back plate comprises a conductive layer and a first protective layer;

the conducting layer is arranged on one side, away from the substrate, of the first annular supporting layer, the first protective layer is arranged on one side, away from the substrate, of the conducting layer, and the second annular supporting layer is arranged on one side, away from the substrate, of the first protective layer; alternatively, the first and second electrodes may be,

the first protective layer is arranged on one side, away from the substrate, of the first annular supporting layer, the conducting layer is arranged on one side, away from the substrate, of the first protective layer, and the second annular supporting layer is arranged on one side, away from the substrate, of the conducting layer.

Optionally, the back plate further includes an isolation ring, and the isolation ring is disposed between the conductive layer and the annular protection layer; alternatively, the first and second electrodes may be,

the conducting layer is provided with an annular isolation hole, and the first protection layer comprises an annular isolation convex part arranged in the annular isolation hole.

Optionally, the back plate includes a conductive layer, a first protective layer and a second protective layer, the first protective layer is disposed on one side of the first annular supporting layer away from the substrate, the conductive layer is disposed on one side of the first protective layer away from the substrate, the second protective layer is disposed on one side of the conductive layer away from the substrate, and the second annular supporting layer is disposed on one side of the second protective layer away from the substrate.

the outer periphery of the first protective layer and the outer periphery of the second protective layer are connected into a whole; alternatively, the first and second electrodes may be,

the conducting layer is provided with an annular isolating hole, and the back plate further comprises an annular isolating part which is arranged in the annular isolating hole and connected with the first protective layer and the second protective layer.

Optionally, the outer annular surface of the annular protection layer is a stepped surface.

Optionally, the annular protection layer includes a first protection ring layer and a second protection ring layer, the first protection ring layer covers the first annular support layer, and the second protection ring layer covers the second annular support layer.

Optionally, the first protective ring layer is integrally connected with the conductive layer of the back plate; and/or the presence of a gas in the gas,

the second protective ring layer is integrally connected with the vibrating diaphragm.

The utility model discloses still provide a microphone, a serial communication port, include:

a package housing; and

the MEMS sensor chip as described above, the MEMS sensor chip is disposed within the package housing.

The utility model also provides an electronic equipment, a serial communication port, include as above microphone.

The utility model discloses in, set up the annular protection layer that covers first annular supporting layer and/or second annular supporting layer at least through the outside at the response subassembly, make the annular protection layer can protect the outer peripheral edges of first annular supporting layer and/or second annular supporting layer, in order to avoid it to be corroded at preparation MEMS sensor chip in-process, thereby can guarantee or provide the reliability of first annular supporting layer and/or second annular supporting layer, thereby can improve the performance and the reliability of microphone, improve the yield of MEMS sensor chip and microphone.

Moreover, the back plate is arranged close to the substrate, so that the distance between the induction assembly and the substrate can be favorably reduced, namely, the thickness of the first annular supporting layer is favorably reduced, and the miniaturization design is favorably realized.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a first embodiment of a MEMS sensor chip according to the present invention;

FIG. 2 is a schematic structural diagram of the MEMS sensor chip of FIG. 1 before etching;

fig. 3 is a schematic structural diagram of a second embodiment of the MEMS sensor chip of the present invention;

fig. 4 is a schematic structural diagram of a third embodiment of the MEMS sensor chip of the present invention;

fig. 5 is a schematic structural diagram of a fourth embodiment of the MEMS sensor chip of the present invention;

fig. 6 is a schematic structural diagram of a fifth embodiment of the MEMS sensor chip of the present invention;

fig. 7 is a schematic structural diagram of a sixth embodiment of the MEMS sensor chip of the present invention;

fig. 8 is a schematic structural diagram of a seventh embodiment of the MEMS sensor chip of the present invention;

fig. 9 is a schematic structural diagram of an eighth embodiment of the MEMS sensor chip of the present invention;

fig. 10 is a schematic structural diagram of a ninth embodiment of the MEMS sensor chip of the present invention.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				100	MEMS sensor chip	23	Second annular supporting layer
10	Substrate	24	Vibrating diaphragm
				11	Hollow cavity	241	Annular connection part
21	A first annular supporting layer	242	Vibrating part
				22	Back electrode plate	243	Spacer
221	Through hole	30	Annular protective layer
				222	Conductive layer	31	Limiting flanging
223	First protective layer	32	A first protective ring layer
				2231	Annular isolation convex part	33	Second protective ring layer
224	Second protective layer	a	First sacrificial layer
				225	Isolating ring	b	Second sacrificial layer
226	Annular partition

The objects, features and advantages of the present invention will be further described with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts belong to the protection scope of the present invention.

It should be noted that if the embodiments of the present invention are described with reference to "first", "second", etc., the description of "first", "second", etc. is only for descriptive purposes and is not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature.

In addition, the meaning of "and/or" appearing throughout is to include three juxtapositions, exemplified by "A and/or B" including either scheme A, or scheme B, or a scheme in which both A and B are satisfied.

The utility model provides a MEMS sensor chip, mainly used microphone.

In an embodiment of the present invention, as shown in fig. 1, and 3-10, the MEMS sensor chip 100 includes a substrate 10, a sensing component, and an annular protection layer 30.

As shown in fig. 1, and 3-10, the substrate 10 has a cavity 11, and the cavity 11 penetrates through the substrate 10.

As shown in fig. 1, and 3-10, the sensing assembly includes a first annular supporting layer 21, a second annular supporting layer 23, a diaphragm 24, and a back plate 22 having a through hole 221, where the first annular supporting layer 21 is disposed on the substrate 10, the back plate 22 is disposed on a side of the first annular supporting layer 21 away from the substrate 10, the second annular supporting layer 23 is disposed on a side of the back plate 22 away from the substrate 10, and the diaphragm 24 is disposed on a side of the second annular supporting layer 23 away from the substrate 10. In short, the first annular support layer 21 is disposed on the substrate 10, and the first annular support layer 21, the back plate 22, the second annular support layer 23, and the diaphragm 24 are sequentially stacked in a direction away from the substrate 10.

Specifically, as shown in fig. 1, and 3-10, the annular hole of the first annular supporting layer 21 is disposed corresponding to the cavity 11, and the annular hole of the first annular supporting layer 21 is communicated with the cavity 11; the annular hole of the second annular supporting layer 23 is arranged corresponding to the annular hole of the first annular supporting layer 21, and the through hole 221 on the back plate 22 is communicated with the annular hole of the second annular supporting layer 23 and the annular hole of the first annular supporting layer 21.

Specifically, the through hole 221 may be provided in one or more than two (i.e., two or more than two). In this embodiment, the through holes 221 are arranged in plurality at intervals on the back plate 22.

Specifically, the through hole 221 may be used as a sound hole, a pressure relief hole, and a corrosion hole. Specifically, when the MEMS sensor chip 100 is manufactured, the through-hole 221 serves as an etching hole through which an etching liquid passes to facilitate removal of the second sacrificial layer b; when the microphone is assembled or assembled on a main control board of the electronic device, the through hole 221 can be used as a pressure relief hole; when in operation, the through-hole 221 may act as a sound hole for transmitting sound to the diaphragm 24.

The annular protection layer 30 is disposed on the periphery of the sensing assembly, and the annular protection layer 30 at least covers the first annular support layer 21 and/or the second annular support layer 23. In this way, it is possible to facilitate the protection of the first annular support layer 21 and/or the second annular support layer 23 to guarantee/improve the reliability thereof.

Specifically, the diaphragm 24 and the back plate 22 form a parallel plate capacitor. In operation, the diaphragm 24 vibrates under the action of sound waves, which causes the distance between the diaphragm 24 and the back plate 22 to change, so that the capacitance of the parallel plate capacitor changes, and the sound wave signal is converted into an electrical signal.

In order to facilitate the detailed explanation of the function of the annular protection layer 30, the present invention further provides a manufacturing process of the sensor chip, which is as follows:

1. a first sacrificial layer a, a back plate 22, a second sacrificial layer b, and a diaphragm 24 are sequentially (deposited) formed on the substrate 10, wherein a through hole 221 is formed on the back plate 22.

2. As shown in fig. 2, an annular protection layer 30 is formed on the first sacrificial layer a, the back plate 22, the second sacrificial layer b and the periphery side of the diaphragm 24 (deposition), and the annular protection layer 30 covers at least the first sacrificial layer a and/or the second sacrificial layer b.

3. Removing part of the first sacrificial layer a and the second sacrificial layer b (by wet etching or vapor phase HF fumigation with an etching solution such as HF acid or BOE solution) to release the micro-electromechanical structure; meanwhile, the remaining first sacrificial layer a forms a first ring-shaped support layer 21, and the remaining second sacrificial layer b forms a second ring-shaped support layer 23.

In the process of removing part of the first sacrificial layer a and the second sacrificial layer b, since the annular protection layer 30 covers at least the first sacrificial layer a and/or the second sacrificial layer b, the outer periphery of the first sacrificial layer a may not be removed/corroded, and/or the outer periphery of the second sacrificial layer b may not be removed/corroded, so that the annular protection layer 30 may protect the outer periphery of the first sacrificial layer a and/or the second sacrificial layer b, and thus excessive corrosion of the first sacrificial layer a and/or the second sacrificial layer b may be avoided, and thus reliability of the first annular support layer 21 and/or the second annular support layer 23 may be ensured or provided, so that performance and reliability of the microphone may be improved, and yield of the MEMS sensor chip 100 and the microphone may be improved.

That is, the annular protection layer 30 may protect the outer periphery of the first annular support layer 21 and/or the second annular support layer 23 from being corroded during the manufacturing process, so as to ensure or provide the reliability of the first annular support layer 21 and/or the second annular support layer 23, thereby improving the performance and reliability of the microphone, and increasing the yield of the MEMS sensor chip 100 and the microphone.

Moreover, by disposing the back plate 22 close to the substrate 10, the distance between the sensing assembly and the substrate 10 can be advantageously reduced, i.e., the thickness of the first annular supporting layer 21 can be advantageously reduced, thereby facilitating the miniaturization of the design.

In this embodiment, the annular protection layer 30 covers at least the first annular support layer 21 and the second annular support layer 23 to ensure or provide reliability of the first annular support layer 21 and the second annular support layer 23.

Further, as shown in fig. 1, and 3 to 10, the outer circumferential surface of the annular protective layer 30 is a stepped surface.

Specifically, as shown in fig. 1, and 3-10, the back plate 22 protrudes radially (i.e., in a direction away from the center line of the substrate 10) from the second annular supporting layer 23, and the first annular supporting layer 21 protrudes radially (i.e., in a direction away from the center line of the substrate 10) from the back plate 22, so that the shape of the peripheral side of the sensing element is a stepped structure, and the shape of the annular protection layer 30 is adapted to the shape of the peripheral side of the sensing element, so that the thickness of the annular protection layer 30 is relatively uniform, and the protection effect is ensured, so that the outer annular surface of the annular protection layer 30 is a stepped surface.

Of course, in other embodiments, the outer annular surface of the annular protection layer 30 may be a flat surface.

In an embodiment, as shown in fig. 1, and 3-10, the annular protection layer 30 may sequentially cover the first annular support layer 21, the back plate 22, the second annular support layer 23, and the diaphragm 24. Specifically, one end of the annular protection layer 30 is hermetically connected to the upper surface of the substrate 10, and the other end covers the diaphragm 24.

In a specific embodiment, the material of the annular protection layer 30 may be the same as that of the diaphragm 24 (for example, both may be selected as polysilicon), or may be different from that of the diaphragm 24 (for example, the annular protection layer 30 is made of an insulating material, such as silicon nitride, and the diaphragm 24 is made of polysilicon), but the material of the annular protection layer 30 should be different from that of the first sacrificial layer a and the second sacrificial layer b (for example, the first sacrificial layer a and/or the second sacrificial layer b may be selected as silicon oxide, and the like) so as to prevent the annular protection layer 30 from being corroded in the preparation process, which will be described in the following examples.

In a specific embodiment, the back plate 22 may be a double-layer film structure, that is, the back plate 22 includes a conductive layer 222 and a first protective layer 223, which are stacked, and the through hole 221 sequentially penetrates through the conductive layer 222 and the first protective layer 223; the structure may also be a three-layer film structure, that is, the back plate 22 includes a first protection layer 223, a conductive layer 222, and a second protection layer 224, which are stacked, and the through hole 221 sequentially penetrates through the first protection layer 223, the conductive layer 222, and the second protection layer 224; the following examples are given. Of course, in some embodiments, the back plate 22 may be a single-layer conductive layer 222 structure.

When the back plate 22 is configured as a double-layer film structure, the conductive layer 222 may be disposed on a side of the first annular support layer 21 away from the substrate 10, the first protection layer 223 may be disposed on a side of the conductive layer 222 away from the substrate 10, and the second annular support layer 23 may be disposed on a side of the first protection layer 223 away from the substrate 10; it is also possible to provide the first protective layer 223 on a side of the first annular support layer 21 facing away from the substrate 10, to provide the conductive layer 222 on a side of the first protective layer 223 facing away from the substrate 10, and to provide the second annular support layer 23 on a side of the conductive layer 222 facing away from the substrate 10. In the following, an example will be described in which the conductive layer 222 is provided on a side of the first ring-shaped support layer 21 facing away from the substrate 10, and the first protective layer 223 is provided on a side of the conductive layer 222 facing away from the substrate 10.

When the back plate 22 is configured as a three-layer film structure, the first protection layer 223 may be disposed on a side of the first annular support layer 21 away from the substrate 10, the conductive layer 222 is disposed on a side of the first protection layer 223 away from the substrate 10, the second protection layer 224 is disposed on a side of the conductive layer 222 away from the substrate 10, and the second annular support layer 23 is disposed on a side of the second protection layer 224 away from the substrate 10.

In some embodiments, as shown in FIGS. 1, and 3-7, the annular protective layer 30 is integrally connected to the diaphragm 24. In this way, the annular protection layer 30 can be formed (deposited) together when the diaphragm 24 is formed (deposited), so that the manufacturing process of the MEMS sensor chip 100 can be simplified.

In the first embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 1, the back plate 22 is configured as a double-layer film structure, such as the back plate 22 includes a conductive layer 222 and a first protection layer 223, and the first protection layer 223 is disposed on one side of the first annular support layer 21 deviating from the substrate 10, the conductive layer 222 is disposed on one side of the first protection layer 223 deviating from the substrate 10, and the second annular support layer 23 is disposed on one side of the conductive layer 222 deviating from the substrate 10.

In this embodiment, further, as shown in fig. 1, the periphery of the conductive layer 222 is spaced from (the inner surface of) the annular protection layer 30 to prevent the conductive layer 222 from being short-circuited with the annular protection layer 30, so that the conductive layer 222 is prevented from being short-circuited with the diaphragm 24 through the annular protection layer 30.

In this embodiment, further as shown in fig. 1, the back plate 22 further includes a spacer ring 225, and the spacer ring 225 is disposed between the conductive layer 222 and the annular protection layer 30. Specifically, the isolation ring 225 is made of an insulating material, and the isolation ring 225 is located in a space between (an inner surface of) the annular protection layer 30 and the periphery of the conductive layer 222. In this way, better isolation can be achieved to prevent short circuits.

In this embodiment, the spacer ring 225 may be either a separate component or may be integrally connected to the first protective layer 223.

In this embodiment, the material of the diaphragm 24 may be polysilicon, the material of the annular protection layer 30 may be polysilicon, and the material of the conductive layer 222 may be polysilicon.

In this embodiment, the material of the first protection layer 223 may be silicon nitride, and the material of the first ring-shaped support layer 21 and/or the second ring-shaped support layer 23 may be silicon oxide.

In the second embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 3, the back plate 22 is configured as a double-layer film structure, for example, the back plate 22 includes a conductive layer 222 and a first protection layer 223, and the first protection layer 223 is disposed on one side of the first annular support layer 21 deviating from the substrate 10, the conductive layer 222 is disposed on one side of the first protection layer 223 deviating from the substrate 10, and the second annular support layer 23 is disposed on one side of the conductive layer 222 deviating from the substrate 10.

In this embodiment, further, as shown in fig. 3, the conductive layer 222 has an annular isolation hole. Specifically, the annular isolation hole divides the conductive layer 222 into an outer ring portion integrally connected to the annular protection layer 30 and a conductive portion located inside the outer ring portion. Thus, the conductive portion is prevented from being short-circuited with the annular protection layer 30, thereby preventing the conductive portion from being short-circuited with the diaphragm 24 through the annular protection layer 30.

In this embodiment, further, as shown in fig. 3, the first protection layer 223 includes an annular isolation convex portion 2231 disposed in the annular isolation hole. Therefore, the isolation can be better realized to prevent short circuit; the structure can also be simplified. The annular isolation convex portions 2231 may be provided separately from the first protective layer 223.

In the third embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 4, the diaphragm 24 includes an annular connecting portion 241 integrally connected to the annular protecting layer 30, and a vibrating portion 242 disposed inside the annular connecting portion 241, wherein the vibrating portion 242 is spaced from the annular connecting portion 241. Thus, the vibration part 242 is prevented from being short-circuited with the ring-shaped protection layer 30, and the vibration part 242 is prevented from being short-circuited with the back plate 22 through the ring-shaped protection layer 30.

In this embodiment, as shown in fig. 4, the diaphragm 24 further includes an isolator 243, and the isolator 243 is at least partially disposed in the space between the vibrating portion 242 and the annular connecting portion 241. Specifically, the spacer 243 is made of an insulating material. In this way, better isolation can be achieved to prevent short circuits.

In this embodiment, the cross-sectional shape of the separator 243 is optionally T-shaped, as shown in fig. 4.

In this embodiment, optionally, as shown in fig. 4, the separator 243 is an annular structure.

In this embodiment, optionally, as shown in fig. 4, the back plate 22 is provided as a double-layer film structure, for example, the back plate 22 includes a conductive layer 222 and a first protective layer 223, and the first protective layer 223 is provided on the side of the first annular support layer 21 facing away from the substrate 10, the conductive layer 222 is provided on the side of the first protective layer 223 facing away from the substrate 10, and the second annular support layer 23 is provided on the side of the conductive layer 222 facing away from the substrate 10.

In addition, it should be noted that the technical solutions in the above embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention. For example, the diaphragm 24 may include an annular connecting portion 241 and a vibrating portion 242 that are spaced apart from each other, the periphery of the conductive layer 222 may be spaced apart from (the inner surface of) the annular protective layer 30, or the conductive layer 222 may have an annular isolation hole.

In the fourth embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 5, the back plate 22 is a three-layer film structure, that is, the back plate 22 includes a conductive layer 222, a first protection layer 223 and a second protection layer 224, the first protection layer 223 is disposed on one side of the first annular support layer 21 deviating from the substrate 10, the conductive layer 222 is disposed on one side of the first protection layer 223 deviating from the substrate 10, the second protection layer 224 is disposed on one side of the conductive layer 222 deviating from the substrate 10, and the second annular support layer 23 is disposed on one side of the second protection layer 224 deviating from the substrate 10.

In this embodiment, further, as shown in fig. 5, the periphery of the conductive layer 222 is spaced from (the inner surface of) the annular protection layer 30 to prevent the conductive layer 222 from being short-circuited with the annular protection layer 30, so that the conductive layer 222 is prevented from being short-circuited with the diaphragm 24 through the annular protection layer 30.

In this embodiment, further as shown in fig. 5, the back plate 22 further includes a spacer ring 225, and the spacer ring 225 is disposed between the conductive layer 222 and the annular protection layer 30. Specifically, the isolation ring 225 is made of an insulating material, and the isolation ring 225 is located in a space between (an inner surface of) the annular protection layer 30 and the periphery of the conductive layer 222. In this way, better isolation can be achieved to prevent short circuits.

In this embodiment, the isolation ring 225 may be either a separate component or may be integrally connected to the first protective layer 223 and/or the second protective layer 224. It is understood that, when the isolating ring 225 is integrally connected to the first protection layer 223 and the second protection layer 224, the outer periphery of the first protection layer 223 is integrally connected to the outer periphery of the second protection layer 224.

In this embodiment, the material of the first protection layer 223 and the second protection layer 224 may be silicon nitride or the like, and the material of the first ring-shaped support layer 21 and/or the second ring-shaped support layer 23 may be silicon oxide or the like.

In the fifth embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 6, the back plate 22 is a three-layer film structure, that is, the back plate 22 includes a conductive layer 222, a first protection layer 223 and a second protection layer 224, the first protection layer 223 is disposed on one side of the first annular support layer 21 deviating from the substrate 10, the conductive layer 222 is disposed on one side of the first protection layer 223 deviating from the substrate 10, the second protection layer 224 is disposed on one side of the conductive layer 222 deviating from the substrate 10, and the second annular support layer 23 is disposed on one side of the second protection layer 224 deviating from the substrate 10.

In this embodiment, further, as shown in fig. 6, the conductive layer 222 has an annular isolation hole. Specifically, the annular isolation hole divides the conductive layer 222 into an outer ring portion integrally connected to the annular protection layer 30 and a conductive portion located inside the outer ring portion. Thus, the conductive portion is prevented from being short-circuited with the annular protection layer 30, thereby preventing the conductive portion from being short-circuited with the diaphragm 24 through the annular protection layer 30.

In this embodiment, further, as shown in fig. 6, the back plate 22 further includes an annular isolation portion 226 disposed in the annular isolation hole and connecting the first protection layer 223 and the second protection layer 224. In this way, better isolation can be achieved to prevent short circuits.

In the sixth embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 7, the diaphragm 24 includes an annular connecting portion 241 integrally connected to the annular protecting layer 30, and a vibrating portion 242 disposed inside the annular connecting portion 241, and the vibrating portion 242 is disposed at an interval from the annular connecting portion 241. Thus, the vibration part 242 is prevented from being short-circuited with the ring-shaped protection layer 30, and the vibration part 242 is prevented from being short-circuited with the back plate 22 through the ring-shaped protection layer 30.

In this embodiment, as shown in fig. 7, the diaphragm 24 further includes an isolator 243, and the isolator 243 is at least partially disposed in the space between the vibrating portion 242 and the annular connecting portion 241. Specifically, the spacer 243 is made of an insulating material. In this way, better isolation can be achieved to prevent short circuits.

In this embodiment, the cross-sectional shape of the separator 243 is optionally T-shaped, as shown in fig. 7.

In this embodiment, optionally, as shown in fig. 7, the separator 243 is an annular structure.

In this embodiment, optionally, the back plate 22 is a three-layer film structure, that is, the back plate 22 includes a conductive layer 222, a first protective layer 223 and a second protective layer 224, the first protective layer 223 is disposed on a side of the first annular support layer 21 facing away from the substrate 10, the conductive layer 222 is disposed on a side of the first protective layer 223 facing away from the substrate 10, the second protective layer 224 is disposed on a side of the conductive layer 222 facing away from the substrate 10, and the second annular support layer 23 is disposed on a side of the second protective layer 224 facing away from the substrate 10.

It should be noted that the technical solutions in the fourth, fifth and sixth embodiments can be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or can not be realized, the combination of the technical solutions should not be considered to exist, and is not within the protection scope of the present invention. For example, the diaphragm 24 may include an annular connecting portion 241 and a vibrating portion 242 that are spaced apart from each other, the periphery of the conductive layer 222 may be spaced apart from (the inner surface of) the annular protective layer 30, or the conductive layer 222 may have an annular isolation hole.

In some embodiments, as shown in fig. 8 and 9, the annular protective layer 30 may also be an insulating protective layer. In this way, short-circuiting of the diaphragm 24 and the back plate 22 by the annular protective layer 30 can be avoided. In this embodiment, the material of the annular protection layer 30 may be selected from silicon nitride, etc. The following description will be made with reference to a specific structure of the back plate 22.

In the seventh embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 8, the annular protection layer 30 is an insulating protection layer, the back plate 22 is configured as a double-layer film structure, for example, the back plate 22 includes a conductive layer 222 and a first protection layer 223, and the first protection layer 223 is disposed on one side of the first annular support layer 21 deviating from the substrate 10, the conductive layer 222 is disposed on one side of the first protection layer 223 deviating from the substrate 10, and the second annular support layer 23 is disposed on one side of the conductive layer 222 deviating from the substrate 10.

In this embodiment, specifically, as shown in fig. 8, one end of the annular protection layer 30 is provided with a limiting flange 31, and the limiting flange 31 is provided on the side of the diaphragm 24 away from the substrate 10.

In the eighth embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 9, that is, the back plate 22 includes a conductive layer 222, a first protective layer 223 and a second protective layer 224, the first protective layer 223 is disposed on one side of the first annular supporting layer 21 departing from the substrate 10, the conductive layer 222 is disposed on one side of the first protective layer 223 departing from the substrate 10, the second protective layer 224 is disposed on one side of the conductive layer 222 departing from the substrate 10, and the second annular supporting layer 23 is disposed on one side of the second protective layer 224 departing from the substrate 10.

In this embodiment, specifically, as shown in fig. 9, one end of the annular protection layer 30 is provided with a limiting flange 31, and the limiting flange 31 is provided with a side of the diaphragm 24 facing away from the substrate 10.

Of course, in a specific embodiment, the annular protection layer 30 may be provided in other structural forms to realize "at least cover the first annular support layer 21 and/or the second annular support layer 23".

As in the ninth embodiment of the MEMS sensor chip 100 of the present invention, as shown in fig. 10, the annular protection layer 30 includes a first protection ring layer 32 and a second protection ring layer 33, the first protection ring layer 32 covers the first annular support layer 21, and the second protection ring layer 33 covers the second annular support layer 23. In this way, the outer peripheries of the first and second annular support layers 21 and 23 may also be protected from corrosion during the preparation of the MEMS sensor chip 100, so that the reliability of the first and second annular support layers 21 and 23 may be ensured or provided.

In this embodiment, as shown in fig. 10, optionally, the first protective ring layer 32 is integrally connected with the conductive layer 222 of the back plate 22; and/or the second protective ring layer 33 is integrally connected with the diaphragm 24 to simplify the structure. Of course, the first protective ring layer 32 and/or the second protective ring layer 33 may be provided as an insulating protective layer.

In addition, it should be specifically noted that the technical solutions in the above embodiments may be combined with each other, but it must be based on the realization of those skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination of technical solutions should not be considered to exist, and is not within the protection scope of the present invention.

The utility model discloses still provide a microphone, include:

a package housing;

This MEMS sensor chip's concrete structure refers to above-mentioned embodiment, because the utility model discloses the microphone has adopted the whole technical scheme of above-mentioned all embodiments, consequently has all beneficial effects that the technical scheme of above-mentioned embodiment brought at least, no longer gives unnecessary details here.

The utility model also provides an electronic equipment, this electronic equipment include main control board and microphone, the microphone is connected with the main control board electricity. The concrete structure of this microphone refers to above-mentioned embodiment, because the utility model discloses electronic equipment has adopted the whole technical scheme of above-mentioned all embodiments, consequently has all beneficial effects that the technical scheme of above-mentioned embodiment brought at least, no longer gives unnecessary details here.

The electronic equipment can be selected from electronic equipment such as a mobile phone, a tablet personal computer, a camera, a hearing aid, an intelligent toy or a monitoring device.

The above is only the optional embodiment of the present invention, and not the scope of the present invention is limited thereby, all the equivalent structure changes made by the contents of the specification and the drawings are utilized under the inventive concept of the present invention, or the direct/indirect application in other related technical fields is included in the patent protection scope of the present invention.

Claims

1. A MEMS sensor chip, comprising:

a substrate having a cavity;

2. The MEMS sensor chip of claim 1, wherein the annular protective layer covers the first annular support layer, the backplate, the second annular support layer, and the diaphragm in that order.

3. The MEMS sensor chip of claim 2, wherein the annular protective layer is integrally connected to the diaphragm.

4. The MEMS sensor chip of claim 3, wherein the diaphragm includes an annular connection portion integrally connected to the annular protection layer, and a vibration portion disposed inside the annular connection portion, the vibration portion being spaced apart from the annular connection portion.

5. The MEMS sensor chip of claim 4, wherein the diaphragm further comprises an isolator disposed at least partially within a space between the vibrating portion and the annular connection portion.

6. The MEMS sensor chip of claim 2, wherein the annular protective layer is an insulating protective layer.

7. The MEMS sensor chip of any one of claims 2 to 6, wherein the back plate comprises a conductive layer and a first protective layer;

8. The MEMS sensor chip of claim 7, wherein the back plate further comprises an isolation ring disposed between the conductive layer and the annular protective layer; alternatively, the first and second electrodes may be,

9. The MEMS sensor chip of any one of claims 2 to 6, wherein the back plate comprises a conductive layer, a first protective layer, and a second protective layer, the first protective layer being disposed on a side of the first annular support layer facing away from the substrate, the conductive layer being disposed on a side of the first protective layer facing away from the substrate, the second protective layer being disposed on a side of the conductive layer facing away from the substrate, the second annular support layer being disposed on a side of the second protective layer facing away from the substrate.

10. The MEMS sensor chip of claim 9, wherein the back plate further comprises an isolation ring disposed between the conductive layer and the annular protective layer; alternatively, the first and second electrodes may be,

11. The MEMS sensor chip of any one of claims 2 to 6, wherein the outer annular surface of the annular protective layer is a stepped surface.

12. The MEMS sensor chip of claim 1, wherein the ring-shaped protective layer comprises a first protective ring layer overlying the first ring-shaped support layer and a second protective ring layer overlying the second ring-shaped support layer.

13. The MEMS sensor chip of claim 12, wherein the first guard ring layer is integrally connected with the conductive layer of the back plate; and/or the presence of a gas in the gas,

14. A microphone, comprising:

a package housing; and

the MEMS sensor chip of any one of claims 1 to 13, disposed within the package housing.

15. An electronic device comprising the microphone of claim 14.