CN212851001U - Microphone chip and MEMS microphone - Google Patents

Abstract

The utility model discloses a microphone chip and MEMS microphone, the microphone chip includes: the chip structure comprises a semiconductor substrate, and a back plate and a vibrating diaphragm which are oppositely arranged on the semiconductor substrate; the dustproof structure is arranged above the back plate and at least partially shields the perforated area of the back plate. Therefore according to the utility model discloses microphone chip failure rate is low, long service life and sensitivity are high.

Description

Microphone chip and MEMS microphone

Technical Field

The utility model relates to a microphone technical field, concretely relates to microphone chip and MEMS microphone.

Background

For the microphone, after the chip is manufactured by the MEMS process, in transportation, packaging and normal use, the pollution particles such as dust floating in the air may float on the back plate of the microphone and enter between the back plate and the diaphragm through the sound hole on the back plate, causing the diaphragm to fail to vibrate normally, so that the microphone chip fails, which is the highest failure mode at present. In the related art, a mesh-shaped film is adhered to a sound inlet hole of a microphone during a microphone packaging process to filter out dust and other pollution particles in the air. However, this structure has no way of preventing particle contamination of the microphone chip before packaging and in transportation, and the mesh film is easily peeled off in use, resulting in failure of the microphone.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a microphone chip, microphone chip can prevent that the pollution granule from getting into between vibrating diaphragm and the back plate, reduces particle pollution, reduces the failure rate.

In order to solve the above technical problem, the present invention provides a microphone chip.

According to the utility model discloses microphone chip includes: the chip structure comprises a semiconductor substrate, and a back plate and a vibrating diaphragm which are oppositely arranged on the semiconductor substrate; the dustproof structure is arranged above the back plate and at least partially shields the perforated area of the back plate.

From this, according to the utility model discloses microphone chip, through setting up dustproof construction, in transportation, encapsulation and normal use, can prevent that the pollution granule in the environment from wafting and falling between back plate and vibrating diaphragm, avoids influencing the normal vibration of vibrating diaphragm to can reduce microphone chip's failure rate, improve microphone chip's life, reduce cost also can improve microphone chip's sensitivity.

According to some embodiments of the utility model, dustproof construction includes shielding plate and supporting part, the shielding plate with the back plate is spaced apart from the setting in upper and lower direction and is exposed the electrode connecting portion of chip architecture, supporting part joint support is in the back plate with between the shielding plate.

Optionally, the shielding plate shields the opening region of the back plate.

Optionally, the shielding plate corresponds to the shape of the opening region of the back plate to cover the opening region of the back plate.

Further, the shielding plate is formed in a circular shape.

Optionally, the shielding plate is formed with a notch exposing the electrode connection part.

Optionally, the shielding plate is formed with a through hole corresponding to the electrode connection part to expose the electrode connection part.

Optionally, the support part comprises a plurality of support members spaced apart along the circumferential direction of the shielding plate, and the plurality of support members surround the opening region of the back plate.

Further, the supporter is formed in a cylindrical shape.

Optionally, the support is formed in a plate shape surrounding an opening region of the back plate to shield the opening region at a side of the opening region.

Optionally, the support is formed as an outwardly projecting arcuate plate.

Optionally, the support is disposed at a corner of the back plate and extends along a corner shape of the back plate to surround the opening region.

Optionally, the dustproof structure further comprises a blocking portion, and the blocking portion is arranged on the supporting pieces and between the adjacent supporting pieces.

Optionally, a blocking portion is formed between any adjacent supporting members.

Optionally, the barrier is formed as a barrier plate.

Optionally, the blocking portion includes a first blocking member and a second blocking member, the first blocking member and the second blocking member are respectively disposed on adjacent supports, and the first blocking member and the second blocking member are disposed at a distance and at least partially overlap in a direction surrounding the opening area.

Further, the first blocking member and the second blocking member are respectively formed in a plate shape, the first blocking member extends obliquely toward the opening area, and the second blocking member is provided outside the first blocking member and extends obliquely away from the opening area.

Optionally, the support portion and the shutter are integrally formed.

The utility model also provides a MEMS microphone.

According to the utility model discloses MEMS microphone, including above-mentioned embodiment the microphone chip.

Drawings

Fig. 1 is a schematic structural diagram of a microphone chip according to an embodiment of the present invention;

fig. 2 is a schematic cross-sectional view of a support portion of a microphone chip according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a microphone chip according to another embodiment of the present invention;

fig. 4 is a schematic cross-sectional view of a support portion of a microphone chip according to another embodiment of the present invention;

fig. 5 is a schematic cross-sectional view of a support portion of a microphone chip according to yet another embodiment of the present invention;

fig. 6 is a schematic cross-sectional view of a support portion of a microphone chip according to yet another embodiment of the present invention;

fig. 7 is a schematic structural diagram of a microphone chip according to another embodiment of the present invention;

fig. 8 is a schematic cross-sectional view of a support portion of a microphone chip according to yet another embodiment of the present invention;

fig. 9 is a schematic cross-sectional view of a support portion of a microphone chip according to yet another embodiment of the present invention;

FIG. 10 is an enlarged view of portion A of FIG. 9;

fig. 11 is a schematic cross-sectional view of a support portion of a microphone chip according to yet another embodiment of the present invention;

fig. 12 is an enlarged view of a portion B in fig. 11.

Reference numerals:

100: a microphone chip;

1: semiconductor substrate, 11: silicon substrate, 12: first sacrificial layer, 13: second sacrificial layer, 14: vibrating diaphragm;

2: chip structure, 21: back plate, 22: an opening area;

3: dustproof structure, 31: shielding plate, 311: notch, 312: through hole, 32: a support part for supporting the support part,

33: support, 34: blocking portion, 35: first stopper, 36: a second barrier.

Detailed Description

The microphone chip provided by the present invention will be described in further detail with reference to the accompanying drawings and the detailed description.

The microphone chip 100 according to an embodiment of the present invention is described below with reference to the drawings.

With reference to fig. 1, fig. 3 and fig. 7, according to the utility model discloses a microphone chip 100 includes chip architecture 2 and dustproof construction 3, chip architecture 2 includes semiconductor substrate 1 and forms on semiconductor substrate 1 and relative backplate 21 and the vibrating diaphragm 14 that sets up, specifically, vibrating diaphragm 14 forms in semiconductor substrate 1, vibrating diaphragm 14 is at semiconductor substrate 1, be formed with the cavity between backplate 21 and the vibrating diaphragm 14, be formed with the trompil region 22 with the intercommunication of cavity on the backplate 21, thus, the air vibration that sound produced transmits to the vibration cavity through trompil region 22, and transmit to vibrating diaphragm 14, make the distance between vibrating diaphragm 14 and the backplate 21 change, and then the electric capacity that backplate 21 and vibrating diaphragm 14 constitute changes, thereby realize converting the sound signal into the signal of telecommunication.

Dustproof construction 3 is established above backplate 21 and at least part shelters from the trompil region 22 of backplate 21, dustproof construction 3 forms in the top of the trompil region 22 of backplate 21 promptly, can shelter from at least a part of the trompil region 22 of backplate 21 through dustproof construction 3, preferably, dustproof construction 3 can shelter from the trompil region 22 of backplate 21 completely, and thus, shelter from the trompil region 22 through dustproof construction 3, can prevent that dust granule in the air etc. from falling on backplate 21 and vibrating diaphragm 14, avoid leading to backplate 21 and vibrating diaphragm 14 unable normal work because the pollution granule enters into between backplate 21 and vibrating diaphragm 14, and then can avoid the inefficacy of microphone chip 100 that leads to from this.

From this, according to the utility model discloses microphone chip 100, through setting up dustproof construction 3, in transportation, encapsulation and normal use, can prevent that the pollution granule in the environment from wafting on back plate 21 and vibrating diaphragm 14, influence the normal motion of vibrating diaphragm to can reduce microphone chip 100's failure rate, improve microphone chip 100's life, reduce cost also can improve microphone chip 100's sensitivity.

As shown in fig. 1, 3 and 7, the semiconductor substrate 1 may include a silicon substrate 11, a first sacrificial layer 12 and a second sacrificial layer 13, which are stacked, a diaphragm 14 is formed between the first sacrificial layer 12 and the second sacrificial layer 13, a back plate 21 is formed on an upper surface of the second sacrificial layer 13, an opening region 22 corresponding to the diaphragm 14 is formed on the back plate 21, and the dust-proof structure 3 is formed above the back plate 21.

As shown in fig. 1 to 8, the dustproof structure 3 may include a shielding plate 31 and a supporting portion 32, the shielding plate 31 is disposed above the back plate 21 and spaced apart from the back plate 21 in the up-down direction, and exposes the electrode connecting portion of the chip structure 2, so that the shielding plate 31 can prevent the contaminant particles from entering between the back plate 21 and the diaphragm 14, and the shielding plate 31 does not shield the electrode connecting portion of the chip structure 2, that is, the electrode connecting portion of the chip structure 2 exposes the shielding plate 31, thereby facilitating the electrical connection of the electrode connecting portion of the chip structure 2.

The supporting portion 32 is connected and supported between the chip structure 2 and the shielding plate 31, so that not only can the shielding plate 31 and the chip structure 2 be supported and fixed, but also the shielding plate 31 can be supported by the supporting portion 32, the shielding plate 31 is spaced apart from the back plate 21 on the chip structure 2, and sound can be conveniently transmitted to the diaphragm 14 through air, further, pollution particles can be prevented from entering between the back plate 21 and the diaphragm 14 from the side portion through the supporting portion 32, so that the effect of particle pollution is further improved, and the sensitivity of the microphone chip 100 is improved.

Alternatively, as shown in fig. 1, the supporting portion 32 may be connected between the back plate 21 and the shielding plate 31, that is, the lower end of the supporting portion 32 is connected to the back plate 21, so as to surround the opening region 22 of the back plate 21, not only to shield the opening region 22, but also to make the volume of the microphone chip 100 relatively small. As shown in fig. 3, the supporting portion 32 may be supported on the upper surface of the chip structure 2 without being connected to the back plate 21, for example, the supporting portion 32 may be supported on other structures on the surface of the chip structure 2 as long as it can support the shielding plate 31 shielding the back plate 21.

Alternatively, the supporting portion 32 and the shielding plate 31 are integrally formed, so that the supporting portion 32 and the shielding plate 31 are an integral structure, which not only can enhance the structural strength of the dust-proof structure 3, but also can simplify the forming process of the shielding plate 32 and the supporting portion 32.

In some embodiments of the present invention, the shielding plate 31 shields the opening region 22 of the back plate 21, as shown in fig. 1, fig. 3 and fig. 7, the shielding plate 31 is disposed above the back plate 21 and parallel to the back plate 21, and the opening region 22 of the back plate 21 can be completely shielded by the shielding plate 31, so that the pollution particles can be further prevented from falling into the space between the back plate 21 and the vibrating diaphragm 14 from the opening region 22, thereby improving the effect of the shielding plate 31 that the particle pollution causes the vibrating diaphragm 14 to fail to work.

In some specific examples of the present invention, the shielding plate 31 corresponds to the shape of the opening region of the back plate 21 to cover the opening region 22 of the back plate 21, that is, the shape of the shielding plate 31 matches the shape of the back plate 21, the opening region 22 of the back plate 21 can be completely shielded by the shielding plate 31, and the shielding plate 31 does not shield the electrode connecting portion of the chip structure 2. For example, as shown in fig. 1, the opening region 22 of the back plate 21 is formed in a circular shape, and the shielding plate 31 is formed in a circular shape and is disposed above the opening region 22 of the back plate 21 so as to completely cover the opening region 22 of the back plate 21.

In other examples of the present invention, the shielding plate 31 may be formed in other shapes, for example, the shielding plate 31 may be formed in a polygon, a square, a rectangle, or the like, or the shielding plate 31 may be formed in an irregular pattern, and the present invention is not limited thereto as long as the opening region 22 of the back plate 21 can be shielded.

Alternatively, the shape of the shielding plate 31 may correspond to the shape of the back plate 21, that is, the shielding plate 31 has substantially the same shape as the back plate 21, for example, the back plate 21 is formed in a square shape, and the shielding plate 31 may also be formed in a square shape and shield the upper surface of the back plate 21, so that the shielding plate 31 has a simple structure and is convenient for shielding the opening region 22 of the back plate 21, wherein the shielding plate 31 may have a notch 311 formed thereon corresponding to the electrode connecting portion of the chip structure 2, so that the electrode connecting portion can be exposed through the notch 311 for electrical connection with other components.

Alternatively, as shown in fig. 3, the shielding plate 31 has a shape that matches the shape of the back plate 21 and completely shields the upper surface of the back plate 21, the shielding plate 31 is formed with a through hole 312 corresponding to the electrode connecting portion to expose the electrode connecting portion, the through hole 312 facilitates electrical connection between the electrode connecting portion and other components, and the shielding area of the shielding plate 31 can be further enlarged to reduce the falling of pollution particles.

As for the support portion 32, the support portion 32 may be vertically connected between the shielding plate 31 and the back plate 21 to support the shielding plate 31. As shown in fig. 1 to 9 and 11, the supporting portion 32 may include a plurality of supporting members 33 spaced apart from each other in the circumferential direction of the shielding plate 31, and the plurality of supporting members 33 are disposed around the opening region 22 of the back plate 21. Alternatively, a plurality of supporting members 33 may be provided at regular intervals along the circumferential direction of the shielding plate 31, which can make the structure of the microphone chip 100 more stable. As shown in fig. 5, 7 and 8, the plurality of supporting members 33 may be formed in a column shape, that is, each supporting member 33 may be formed as a supporting column, and the arrangement and number and height of the plurality of supporting columns may be adjusted and selected according to actual situations.

In other examples of the present invention, as shown in fig. 1 to 4 and fig. 6, the supporting member 33 may be formed in a plate shape to shield the opening region 22 at a side portion of the opening region 22, in other words, the supporting member 33 may be formed as a supporting plate, and the back plate 21 may be shielded from the side portion by the supporting plate to laterally shield the back plate 21, so that not only the effect of preventing the diaphragm 14 from normally operating due to particle contamination can be improved, but also the supporting effect of the supporting portion 32 and the back plate 21 and the shielding plate 31 can be enhanced.

As shown in fig. 1 and 2, the supporting members 33 may be formed as arc plates protruding outward, and a plurality of supporting members 33 are spaced around the opening region 22 of the back plate 21. As shown in fig. 6, the support member 33 is formed as a flat plate having a width direction coinciding with a width direction of the edge of the back plate 21. As shown in fig. 3 and 4, the supporters 33 may be provided at corners of the back plate 21, each supporter 33 is formed in a plate-shaped structure, and the plate-shaped structure of each supporter 33 is adapted to the corner shape of the back plate 21, for example, the cross-section of the supporter 33 is formed in a semi-enclosed structure having the same shape as the corner shape.

In the example shown in fig. 1 and 2, the shielding plate 31 is formed in a circular shape, the supporting members 33 are formed in a columnar shape, the number of the supporting members 33 may be four, and the four supporting members 33 are evenly spaced apart in the circumferential direction of the shielding plate 31. In the example shown in fig. 3 and 4, the shielding plate 31 may be formed in a square shape and correspond to the shape of the back plate 21, and a plurality of supporting members 33 are provided at the edges of the shielding plate 31 and the back plate 21, arranged along the extending direction of the four sides of the shielding plate 31 and the back plate 21, for example, the number of the supporting members 33 may be four, and the four supporting members 33 may be respectively provided at the four corners of the shielding plate 31. In the example shown in fig. 7 and 8, the shielding plate 31 is provided with notches 311 corresponding to the electrode connecting portions, and the supporting members 33 may be six, with six supporting members 33 being provided at intervals along the edge shape of the shielding plate 31.

In some embodiments of the present invention, as shown in fig. 9-12, the dust-proof structure 3 may further include a blocking portion 35, the blocking portion 35 is disposed on the supporting member 33 and disposed between the adjacent supporting members 33, the adjacent supporting members 33 are spaced apart and have a certain spacing gap, the blocking portion 35 is formed on one side of the supporting member 33 facing the spacing gap, so that the blocking portion 35 can enter from the spacing gap between the supporting members 33 through the blocking portion 35 and float to the back plate 21.

Preferably, a blocking portion 35 is formed between any two adjacent supporting members 33, that is, a spacing gap between any two adjacent supporting members 33 is provided with the blocking portion 35, so that the effect of placing particle contamination can be further improved. Alternatively, the blocking portion 35 may be formed as a blocking plate, thereby further increasing a blocking area and improving an effect of preventing particle contamination.

In some embodiments of the present invention, as shown in fig. 10 and 12, the blocking portion 35 may include a first blocking member 35 and a second blocking member 36, and the first blocking member 35 and the second blocking member 36 are respectively disposed on the adjacent supporting members 33 and spaced apart from each other. In other words, the first barrier 35 and the second barrier 36 together constitute the barrier portion 35, the first barrier 35 is provided on one of the adjacent two support members 33, the second barrier 36 is provided on the other of the adjacent two support members 33, and the first barrier 35 and the second barrier 36 are each provided between the adjacent two support members 33 and are disposed in a spaced-apart relation to each other, so that by providing the first barrier 35 and the second barrier 36, not only can the effect of preventing particle contamination be enhanced, but also the spaced-apart arrangement of the first barrier 35 and the second barrier 36 can form a certain spacing space to allow sound to be transmitted to the diaphragm 14 by air vibration, and on the other hand, during the manufacturing process of the microphone chip 100, can also allow the corrosive solution to flow into the semiconductor substrate 1 to form the chip configuration 2.

As shown in fig. 10 and 9, a first stopper 35 and a second stopper 36 are respectively formed on a side of the support 33 facing the adjacent other support 33, wherein the first stopper 35 and the second stopper 36 are oppositely disposed, the first stopper 35 and the second stopper 36 are disposed at a distance in a width direction of the gap of the adjacent support 33, and at this time, the first stopper 35 and the second stopper 36 cover a part of the width direction of the gap of the adjacent support 33, so that prevention of particle contamination from the side can be further achieved by the first stopper 35 and the second stopper 36.

As shown in fig. 11 and 12, the first and second stoppers 35 and 36 may be formed in a plate shape, and optionally, the first and second stoppers 35 and 36 may at least partially overlap in a direction surrounding the open hole region 22, that is, the first and second stoppers 35 and 36 cover the width of the gap of the adjacent support 33, and the gap can be completely blocked in the width direction of the gap of the adjacent support 33 by the first and second stoppers 35 and 36, so that the effect of preventing the side portion from particle contamination can be improved, wherein the first and second stoppers 35 and 36 are spaced apart in the length direction of the gap of the adjacent support 33.

In the example shown in fig. 11 and 12, the second stopper 36 is provided outside the first stopper 35, the first stopper 35 is formed as a sloping plate extending obliquely toward the direction in which the aperture area 22 is located, the second stopper 36 is formed as a sloping plate extending obliquely away from the aperture area 22, and the first stopper 35 and the second stopper 36 are provided in parallel and partially overlap.

The utility model also provides a MEMS microphone, the MEMS microphone includes the microphone chip 100 of above-mentioned embodiment.

Therefore according to the utility model discloses MEMS microphone, through the microphone chip 100 that sets up above-mentioned embodiment to can avoid because the vibrating diaphragm 14 that causes between pollution particles entering backplate 21 and the vibrating diaphragm 14 can not normally work, and then can improve MEMS microphone's sensitivity, above-mentioned embodiment microphone chip 100 failure rate is little moreover, also can improve MEMS microphone's life, reduce cost.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims (19)

1. A microphone chip, comprising:

the chip structure comprises a semiconductor substrate, and a back plate and a vibrating diaphragm which are oppositely arranged on the semiconductor substrate;

the dustproof structure is arranged above the back plate and at least partially shields the perforated area of the back plate.

2. The microphone chip according to claim 1, wherein the dust-proof structure includes a shielding plate and a supporting portion, the shielding plate and the back plate are disposed at a distance in an up-down direction and expose the electrode connecting portion of the chip structure, and the supporting portion is connected and supported between the chip structure and the shielding plate.

3. The microphone chip of claim 2, wherein the shielding plate shields the opening region of the backplate.

4. The microphone chip as claimed in claim 3, wherein the shielding plate corresponds to the shape of the opening region of the backplate to cover the opening region of the backplate.

5. The microphone chip according to claim 4, wherein the shielding plate is formed in a circular shape.

6. The microphone chip as defined by claim 3, wherein the shielding plate is formed with a notch exposing the electrode connecting portion.

7. The microphone chip according to claim 3, wherein the shielding plate is formed with a through hole corresponding to the electrode connection part to expose the electrode connection part.

8. The microphone chip as defined by claim 3 wherein the support portion comprises a plurality of support members spaced apart along the circumference of the shielding plate, the plurality of support members surrounding the aperture region of the backplate.

9. The microphone chip according to claim 8, wherein the support member is formed in a columnar shape.

10. The microphone chip according to claim 8, wherein the support is formed in a plate shape surrounding an opening region of the backplate to shield the opening region at a side of the opening region.

11. The microphone chip of claim 10, wherein the support is formed as an outwardly convex arc-shaped plate.

12. The microphone chip of claim 10, wherein the support is disposed at a corner of the backplate and extends along a corner shape of the backplate to surround the opening region.

13. The microphone chip of claim 8, further comprising a blocking portion disposed on the support members and between adjacent support members.

14. The microphone chip of claim 13, wherein a barrier is formed between any adjacent support members.

15. The microphone chip of claim 13, wherein the blocking portion comprises a first blocking member and a second blocking member, the first blocking member and the second blocking member being respectively disposed on adjacent supports and spaced apart.

16. The microphone chip of claim 15, wherein the first barrier and the second barrier at least partially overlap in a direction around the open area.

17. The microphone chip according to claim 16, wherein the first and second stoppers are respectively formed in a plate shape, the first stopper extends obliquely toward the opening area, and the second stopper is provided outside the first stopper and extends obliquely away from the opening area.

18. The microphone chip according to claim 2, wherein the supporting portion and the shielding plate are integrally molded.

19. A MEMS microphone comprising the microphone chip of any one of claims 1 to 18.

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