WO2020173086A1

WO2020173086A1 - Mems sensor and electronic device

Info

Publication number: WO2020173086A1
Application number: PCT/CN2019/107329
Authority: WO
Inventors: 邹泉波; 冷群文
Original assignee: 歌尔微电子有限公司; 北京航空航天大学青岛研究院
Priority date: 2019-02-25
Filing date: 2019-09-23
Publication date: 2020-09-03
Also published as: CN109941956B; CN109941956A

Abstract

A MEMS sensor and an electronic device, wherein a sensitive film layer comprises a sensitive part (1b) and a fixed part (1a); a magnetic detection mechanism comprises a magnet (6) provided on the sensitive part (1b), and further comprises magnetoresistances (3) provided on the fixed part (1a) and located on two opposite sides of the magnet (6) in the X-axis direction respectively; the distances from the centers of the two magnetoresistances (3) to the center of the magnet (6) are equal, and the two magnetoresistances (3) have the same sensing direction, which is in the X-axis direction; and when the sensitive part (1b) vibrates in the Z-axis direction, the resistance value of one of the magnetoresistances (3) becomes larger and the resistance value of the other magnetoresistance (3) becomes smaller, the variation amounts are the same, and the two constitute a Wheatstone bridge. Since it is easy to control the alignment process of the magnet (6) and the magnetoresistances (3), and the magnet (6) and the magnetoresistances (3) may be made smaller, the miniaturization of the sensor is achieved. Meanwhile, it is also easy to improve the detection performance of the sensor.

Description

MEMS sensors and electronic equipment

Technical field

The present invention relates to the field of energy conversion, and more specifically, to a MEMS sensor and an electronic device using the sensor.

Background technique

Existing mainstream sensors, such as microphones, pressure sensors, displacement sensors, etc., are all detected by the principle of plate capacitors. For example, in the structure of a microphone, it usually includes a substrate and a back plate and a diaphragm formed on the substrate. There is a gap between the back plate and the diaphragm, so that the back plate and the diaphragm together form a flat plate. Capacitor sensing structure.

For microphones with this structure, the gap or air flow resistance in the perforations caused by air viscosity becomes the dominant factor in the noise of MEMS microphones, which will limit the high signal-to-noise ratio performance of the microphone to a certain extent, and ultimately lead to poor performance of the microphone. .

For the traditional magnetic sensor structure without backplane, the magnetic sensor and the magnet are respectively placed on two relatively moving planes, and the sound pressure will deform the diaphragm out of the plane, thereby changing the gap between the GMR and the magnet. The sensor with this structure needs to accurately control the gap of the static position, and also needs to align the magnet and the GMR on two planes, which is not easy for semiconductor manufacturing.

Summary of the invention

An object of the present invention is to provide a new technical solution for the sensor.

According to a first aspect of the present invention, there is provided a MEMS sensor, comprising a sensitive film layer carried on a substrate and located in the XY plane, the sensitive film layer including a sensitive part and a fixed part separated from the sensitive part; Including the magnetic detection mechanism arranged on the sensitive part and the fixed part;

The magnetic detection mechanism includes a magnet arranged on the sensitive part, the magnetization direction of the magnet is in the Z-axis direction; and also includes a magnet arranged on the fixed part and located on opposite sides of the magnet in the X-axis direction. Magnetic resistance; the distance between the center of the two magnetic resistances to the center of the magnet is equal, and the sensing directions of the two magnetic resistances are the same, both in the X-axis direction; or,

The magnetic detection mechanism includes a magnet arranged on the fixed part, the magnetization direction of the magnet is in the Z-axis direction; and also includes a magnet arranged on the sensitive part and located on opposite sides of the magnet in the X-axis direction. Magnetic resistance; the distance from the center of the two magnetic resistances to the center of the magnet is equal, and the sensing directions of the two magnetic resistances are the same, both in the X-axis direction;

When the sensitive part vibrates in the Z-axis direction, the resistance value of one magnetoresistance becomes larger, and the resistance value of the other magnetoresistor becomes smaller, and the amount of change is the same. The two constitute a Wheatstone bridge.

Optionally, in the initial position, the center plane of the magnet is coplanar with the center plane of the free magnetic layer in the magnetoresistance.

Optionally, a support layer is further provided between the lower surface of the magnetoresistance and the sensitive film layer.

Optionally, there are multiple magnetic resistances on opposite sides of the magnet, and the number of magnetic resistances on both sides and the distance relative to the magnet are in one-to-one correspondence.

Optionally, there are at least two magnetic detection mechanisms, which are respectively distributed on opposite sides of the sensitive film layer.

Optionally, a first cantilever beam extends outwards from two opposite sides of the sensitive part, and the magnetic detection mechanism is arranged on the first cantilever beam and the fixed part.

Optionally, a first cantilever beam extends outwards on opposite sides of the sensitive part, and a second cantilever beam is provided at the free end of the first cantilever beam; the magnetic detection mechanism is provided on the second cantilever beam and fixed Ministry.

Optionally, it further includes a pre-bending mechanism, the pre-bending mechanism includes a cantilever part separated from the sensitive part and the fixed part on the sensitive film layer, and the cantilever part is provided with a Z-axis direction change between the free end and the sensitive part. The upper relative position of the stress layer; an electrostatic force is applied between the cantilever portion and the sensitive portion to adjust the position of the sensitive portion.

Optionally, the sensitive part is suspended in the back cavity of the substrate, and one of the sides is fixed on the substrate; the magnetic detection mechanism is distributed at a position far away from the sensitive part and the substrate.

Optionally, the sensitive part is suspended in the back cavity of the substrate, and its opposite sides are respectively fixed on the substrate; the magnetic detection mechanism is distributed in the middle of the sensitive part.

Optionally, the MEMS sensor is a MEMS pressure sensor, a MEMS gas sensor, a MEMS microphone, a MEMS temperature sensor, a MEMS humidity sensor or a MEMS displacement sensor.

According to another aspect of the present invention, there is also provided an electronic device including the above-mentioned MEMS sensor.

In the sensor of the present invention, the magnet and the magnetoresistance are located in the same plane, the magnetoresistance electric signal is detected by the displacement in the Z axis direction, and finally the Wheatstone bridge is formed by the magnetoresistance on the opposite sides of the magnet. When the sensor is manufactured, it is easy to control the alignment process of the magnet and the magnetoresistance, and the magnet and the magnetoresistance can be made smaller, which realizes the miniaturization and development of the sensor, and it is also easy to improve the detection performance of the sensor.

Through the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings, other features and advantages of the present invention will become clear.

Description of the drawings

The drawings incorporated in the specification and constituting a part of the specification illustrate the embodiments of the present invention, and together with the description thereof are used to explain the principle of the present invention.

Fig. 1 is a principle diagram of the magnetoresistance detection of the present invention.

Fig. 2 is a schematic diagram of the cooperation of the multi-magnetic resistance and the magnet of the present invention.

Fig. 3 is a schematic diagram of the structure of the sensor of the present invention.

Figure 4 is a schematic diagram of the cooperation between the pre-bending mechanism and the sensitive part of the present invention.

Fig. 5 is a schematic structural diagram of the first embodiment of the sensor of the present invention.

Fig. 6 is a schematic diagram of the second embodiment of the sensor of the present invention.

Fig. 7 is a schematic structural diagram of a third embodiment of the sensor of the present invention.

8a to 8h are flow charts of the manufacturing process of the sensor of the present invention.

Fig. 9a is a simulation diagram of the magnetic field distribution in the embodiment shown in Fig. 2.

Fig. 9b is an enlarged view of the magnetoresistive linear detection area shown in Fig. 9b.

detailed description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless specifically stated otherwise, the relative arrangement, numerical expressions and numerical values of the components and steps set forth in these embodiments do not limit the scope of the present invention.

The following description of at least one exemplary embodiment is in fact only illustrative, and in no way serves as any limitation to the present invention and its application or use.

The technologies, methods, and equipment known to those of ordinary skill in the relevant fields may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be regarded as part of the specification.

In all the examples shown and discussed herein, any specific value should be interpreted as merely exemplary and not as limiting. Therefore, other examples of the exemplary embodiment may have different values.

It should be noted that similar reference numerals and letters indicate similar items in the following drawings, so once a certain item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

The MEMS sensor provided by the present invention may be a MEMS pressure sensor, a MEMS gas sensor, a MEMS microphone, a MEMS temperature sensor, a MEMS humidity sensor, a MEMS displacement sensor, or other sensors well known to those skilled in the art. For example, when applied to a pressure sensor, the sensitive membrane is sensitive to external pressure, and changes in external pressure will drive the sensitive membrane to deform. When applied to a displacement sensor, a driving rod can be set to connect with the sensitive film, and the sensitive film is pushed by the driving rod to deform, which will not be listed here.

The present invention also provides an electronic device using the above MEMS sensor. The electronic device may be a smart device well known to those skilled in the art such as a mobile phone, a tablet computer, a smart bracelet, and smart glasses.

For ease of description, a MEMS microphone is now taken as an example to describe the technical solution of the present invention in detail.

The MEMS sensor provided by the present invention includes a sensitive film layer carried on a substrate and located in a plane. The sensitive film layer includes a sensitive part and a fixed part separated from the sensitive part. A magnetic detection mechanism is arranged on the fixed part and the sensitive part. When the external sound acts on the sensitive part, the sensitive part vibrates in a direction perpendicular to its surface, so that the magnetic detection mechanism outputs a changing electrical signal.

Specifically, referring to FIG. 3, the fixed portion 1a and the sensitive portion 1b are separated from the same sensitive film layer. The sensitive film layer is simultaneously deposited on the substrate during the MEMS manufacturing process, and can be separated by the process of etching the gap 7 open. Among them, part of the edge of the sensitive part 1b can be connected to the substrate, and other parts can be suspended on the substrate (not shown in FIG. 3) to make it sensitive to external sound. The etched gap 7 is also conducive to pressure equalization on both sides of the sensitive part 1b.

The fixing portion 1a is connected to the substrate (not shown in FIG. 3) and is not sensitive to external sounds. In the MEMS manufacturing process, before the sensitive film is released, the sensitive film is on the same level. For example, in a three-axis coordinate system, the sensitive film is in the XY plane.

The magnetic detection mechanism includes a magnet 6 arranged on the sensitive part 1b, and the magnetization direction of the magnet 6 is in the Z-axis direction. The magnet 6 may be in the form of a magnetic thin film, and the magnetic thin film may be directly made of a magnetic material, or the thin film may be magnetized after being formed. In a specific embodiment of the present invention, the magnetic film can be made of CoCrPt or CoPt. The magnet 6 can be formed on the sensitive part 1b by deposition or other means well known to those skilled in the art, which will not be described in detail here.

The magnetic detection mechanism further includes magnetic resistors 3 arranged on the fixed portion 1a and located on opposite sides of the magnet 6 in the X-axis direction. The magnetoresistance 3 preferably adopts a giant magnetoresistive sensor (GMR), a tunnel magnetoresistive sensor (TMR), or an anisotropic magnetoresistive sensor (AMR). By using high-sensitivity giant magnetoresistive sensors (GMR), tunnel magnetoresistive sensors (TMR) or anisotropic magnetoresistive sensors (AMR) to obtain the detected electrical signals, the electrical performance of the detection mechanism can be guaranteed.

FIG. 3 shows only the magnetic resistance 3 on one side of the magnet 6 due to the positional relationship of the sectional view. The two sides of the magnet 6 are respectively provided with magnetic resistors 3, and the distance from the center of the two magnetic resistors 3 to the center of the magnet 6 is equal, and the sensing directions of the two giant magnetic resistors are the same, both in the X-axis direction.

Fig. 1 shows the working principle diagram of the magnetic detection mechanism of the present invention. The magnet is located in the middle of the two magnetic resistors, and the magnetization direction of the magnetic resistors is in the vertical direction. For example, referring to the view direction of FIG. 1, the upper end of the magnet is the N pole and the lower end is the S pole, and the magnetic field direction of the magnet returns from the N pole to the S pole. The center position of the two magnetic resistances to the center of the magnet are the same, and the magnetic resistance and the magnet are both on the same surface. The sensing directions of the two magnetic resistors are the same, for example, the sensing directions of the two magnetic resistors are both facing the positive direction of the X axis.

For those skilled in the art, magnetoresistance usually includes a free magnetic layer, a non-magnetic layer, and a pinned layer. The free magnetic layer is a functional layer of magnetoresistance. Due to the different sizes of magnetoresistance and magnet, in order to ensure the detection performance of the two magnetoresistances, in the initial position, the center plane of the magnet is coplanar with the center plane of the free magnetic layer in the magnetoresistance.

When the magnet is displaced in the Z-axis direction, for example, when the magnet is displaced upwards, the two magnetoresistors sense the change in the magnetic field strength, and the resistance value of one magnetoresistor becomes larger, and the resistance value of the other magnetoresistor becomes smaller , And the amount of change is the same. For example, the magnetic resistances R- and R+ shown in Fig. 1 together can form a Wheatstone bridge to output the detected electrical signal.

Of course, for those skilled in the art, in the magnetic detection mechanism, the magnet can also be placed on the fixed part, and the magnetic resistance can be placed on the sensitive part. When the sensitive part vibrates, the magnetic detection mechanism can also output a changing electrical signal. When installing the magnetoresistance on the sensitive part, it is necessary to consider the influence of the lead wire on the sensitive part when the lead wire is arranged on the sensitive part.

3, the magnet 6 and the magnetoresistor 3 are both arranged on the sensitive film layer. In view of the size of the magnet 6 and the magnetoresistor 3, in order to ensure that the center surface of the magnet 6 is coplanar with the center surface of the free magnetic layer in the magnetoresistor 3. Before the magnet 6 and the magnetoresistor 3 can be deposited and formed, a support layer 2, such as silicon oxide, can be deposited on the fixed portion 1a in advance. The magnetic resistance 3 is formed on the support layer 2 to increase the height of the magnetic resistance 3. The lead 4 can be deposited on the support layer 2 and connected to the magnetoresistor 3 to lead the signal of the magnetoresistor 3. A protective layer 5 can be provided on the surface of the magnetoresistor 3 and the magnet 6 to protect the magnet 6 and the magnetoresistor 3 from damage.

Fig. 2 shows another embodiment of the MEMS sensor of the present invention. There are multiple magnetoresistances on both sides of the magnet, and the number of magnetoresistances on both sides and the distance relative to the magnet are in one-to-one correspondence. For example, in the embodiment illustrated in FIG. 2, three magnetic resistances are provided on the left side of the magnet M, denoted as R1-, R2-, R3-; and three magnetic resistances are provided on the right side of the magnet M, denoted as R1+, R2+, R3+. R1+, R1- correspond, R2+, R2- correspond, R3+, R3- correspond.

In a specific embodiment of the present invention, for example, the center of R1+ and R1- is 3 μm away from the center of magnet M; the center of R2+ and R2- is 4 μm away from the center of magnet M; the center of R3+ and R3- is away from the center of magnet M It is 5μm. According to the characteristics of the magnetic field distribution of the magnet M, the magnetoresistance at different distances has different linear regions, sensitivity, and signal-to-noise ratio. The designer can choose the appropriate distance for combination according to actual needs.

Figures 9a and 9b show simulations of magnetoresistance at different distances in a magnetic field. In the figure, the abscissa represents the displacement of the magnet in the Z axis direction, and the ordinate represents the magnetic field strength Bx(T) and the magnetic field change gradient dBx/dz(T/m). It can be seen from these two simulation graphs that a closer distance leads to a higher magnetic field intensity gradient, so the sensitivity Sb (=dBx/dZ) is higher, but it has a narrower linear region and therefore a narrower dynamic range (Or Acoustic Overload Point, AOP), and it is more difficult to align between the magnet and the magnetic resistance. If multiple magnetoresistances are placed in the same sensor, the best performance can be obtained.

In the MEMS sensor of the present invention, when the sacrificial layer is released, the sensitive film layer will be bent and deformed to a certain extent under the action of stress, which makes it more difficult for the magnet on the sensitive part to align with the magnetoresistance on the fixed part. To this end, the MEMS sensor of the present invention also includes a pre-bending mechanism 9, refer to FIG. 4.

The pre-bending mechanism 9 includes a cantilever portion 1c on the sensitive film layer, and the cantilever portion 1c is separated from the sensitive portion 1b and the fixed portion 1a. For example, the sensitive film layer can be processed by an etching process to form the fixed portion 1a, the sensitive portion 1b, and the cantilever portion 1c that are independent of each other.

One end of the cantilever portion 1c is fixed. For example, in a MEMS structure, one end of the cantilever portion 1c can be fixed on the substrate, and the other end can be suspended in the back cavity of the substrate. A stress layer 8 is deposited on the surface of the cantilever portion 1c. After the cantilever portion 1c is released, the stress layer 8 changes the relative position between the free end of the cantilever portion 1c and the sensitive portion 1b in the Z-axis direction. FIG. 4 shows that the free end of the cantilever portion 1c is higher than the sensitive portion 1b in the Z-axis direction.

When the sensitive film is manufactured, it is formed on the substrate through processes such as deposition, and has a uniform flatness. The stress layer 8 formed at the position of the cantilever portion 1c can be a tensile stress layer or a compressive stress layer according to actual needs. When the sensitive film layer is released, under the stress of the stress layer 8 itself, the cantilever portion 1c is driven to warp (upward or downward) relative to the sensitive portion 1b.

A certain electrostatic force is applied between the cantilever portion 1c and the sensitive portion 1b, so that the sensitive portion 1b can be attracted toward the cantilever portion 1c under the action of the electrostatic force, thereby changing the position of the sensitive portion 1b. Moreover, the degree of displacement of the sensitive part 1b can be adjusted according to the magnitude of the electrostatic force, and finally the purpose of aligning the magnet on the sensitive part 1b with the magnetoresistance on the fixed part 1a is achieved.

Figure 5 shows a specific embodiment of a MEMS sensor of the present invention. In this embodiment, the sensitive part 50 is fixedly connected to the substrate through its fixed end 500, and other positions are suspended on the substrate. The two opposite sides of the sensitive part 50 respectively extend a first cantilever beam 501 outward, and the magnetic detection mechanism is arranged on the first cantilever beam 501 and the fixed part.

Specifically, a magnet 52 is provided on the first cantilever beam 501, and a first magnetic resistance unit 53 and a second magnetic resistance unit 54 are respectively provided on both sides of the first cantilever beam 501. The first magnetoresistive unit 53 and the second magnetoresistive unit 54 on both sides of the same cantilever form a Wheatstone bridge. The magnetic detection mechanisms between different cantilever beams are combined together to jointly output changing electrical signals. Of course, for those skilled in the art, there may be multiple first cantilevers on the same side of the sensitive part 50, which will not be described in detail here.

The pre-bending mechanism 51 is arranged on a side away from the fixed end 500 of the sensitive part 50.

In the embodiment shown in FIG. 6, the difference from the embodiment shown in FIG. 5 is that a second cantilever beam 5002 is provided at the free end of the first cantilever beam 5001; the magnetic detection mechanism is provided on the second cantilever beam 5002 and fixed Ministry.

Specifically, the first cantilever beam 5001 extends from the sensitive part, and the center position of the second cantilever beam 5002 is connected with the first cantilever beam 5001, and the two form a T-shaped structure. Two magnets are respectively provided at both ends of the second cantilever beam 5002, and two magnetoresistive units are respectively provided on two opposite sides of each magnet.

In the embodiment shown in FIG. 7, different from the embodiment shown in FIG. 5, the sensitive portion 50 has fixed ends 500 on opposite sides, which are fixedly connected to the substrate. Other positions of the sensitive part 50 are suspended in the back cavity of the substrate, and the magnetic detection mechanism is distributed in the middle position of the sensitive part 50. That is, the first cantilever beams 501 are respectively on opposite sides of the central area of the sensitive part 50. A plurality of pre-bending mechanisms 51 are provided, which are distributed in the middle position of the sensitive part 50 to ensure the balance of adjustment of the position of the middle region of the sensitive part 50.

8a to 8h show a flow chart of one of the manufacturing processes of the MEMS sensor of the present invention.

Referring to FIG. 8a, an insulating layer 101 and a sensitive film layer 102 are sequentially deposited on the substrate 100. The substrate 100 can be a single crystal silicon substrate, and its thickness can be 0.1-10 μm. The insulating layer 101 can be made of silicon oxide, and the sensitive film layer 102 can be made of materials known to those skilled in the art such as polysilicon. A layer of silicon oxide is continuously deposited on the sensitive film layer 102, and the silicon oxide is patterned to form a support layer 103 at a corresponding position of the sensitive film layer 102.

Referring to FIG. 8b, a magnet 104 is formed on a corresponding position of the sensitive film layer 102 through a lift-off process or a patterning process. For example, when the stripping process is selected, a photoresist can be formed on the sensitive film layer 102, and the photoresist can be etched to form a photolithography pattern; a magnet film layer is deposited on the photoresist by PVD, and finally the photoresist is removed to form a magnet picture of.

For example, when the dry IBE etching process is selected, the magnet film layer can be deposited on the sensitive film layer 102 by means of PVD, and then the magnet film layer can be etched by the IBE process to form the pattern of the magnet.

Referring to FIG. 8c, the magnetoresistance 105 is formed on the support layer 103 through a lift-off process or a patterning process, for example, GMR or TMR may be formed.

Referring to FIG. 8d, a lead 106 is formed on the support layer 103, and the lead 106 is connected to the magnetoresistor 105 to lead the electrical signal of the magnetoresistor 105. The lead 106 can be made of metal aluminum or a conductive film composed of Cr and Au. The lead 106 is connected to the magnetoresistor 105, and conducts the signal of the magnetoresistor 105 to an appropriate position for subsequent lead out. The lead 106 can be formed by PVD combined with Liftoff process or wet etching process, which will not be described in detail here. The molding temperature of PVD is relatively low, and it can even be carried out at room temperature.

Referring to FIG. 8e, a protective layer 107 is deposited on the outer surface of the magnet and magnetoresistive for protection. The protective layer 107 is etched at the position of the lead 106 to expose part of the lead 106.

Referring to FIG. 8f, a pad is formed at a corresponding position of the protective layer 107 to lead out the lead 106.

Referring to FIG. 8g, the sensitive film layer located between the magnet and the magnetoresistance is etched to form a gap 1020 to separate the sensitive film layer into a fixed portion 110 and a sensitive portion 109.

Referring to FIG. 8h, the substrate 100 is etched, and the insulating layer 101 is removed by etching to release the sensitive part 109, and finally the MEMS sensor of the present invention is formed.

Of course, for those skilled in the art, for a sensor with a pre-bending mechanism, the specific structure of the pre-bending mechanism formed in the above steps is also required, which will not be described in detail here.

Although some specific embodiments of the present invention have been described in detail through examples, those skilled in the art should understand that the above examples are only for illustration and not for limiting the scope of the present invention. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present invention. The scope of the invention is defined by the appended claims.

Claims

A MEMS sensor, which is characterized in that it comprises a sensitive film layer carried on a substrate and located in the XY plane, the sensitive film layer includes a sensitive part and a fixed part separated from the sensitive part; Magnetic detection mechanism on the fixed part;

The magnetic detection mechanism includes a magnet arranged on the sensitive part, the magnetization direction of the magnet is in the Z-axis direction; and also includes a magnet arranged on the fixed part and located on opposite sides of the magnet in the X-axis direction. Magnetic resistance; the distance between the center of the two magnetic resistances to the center of the magnet is equal, and the sensing directions of the two magnetic resistances are the same, both in the X-axis direction; or,

The magnetic detection mechanism includes a magnet arranged on the fixed part, the magnetization direction of the magnet is in the Z-axis direction; and also includes a magnet arranged on the sensitive part and located on opposite sides of the magnet in the X-axis direction. Magnetic resistance; the distance from the center of the two magnetic resistances to the center of the magnet is equal, and the sensing directions of the two magnetic resistances are the same, both in the X-axis direction;

When the sensitive part vibrates in the Z-axis direction, the resistance value of one magnetoresistance becomes larger, and the resistance value of the other magnetoresistor becomes smaller, and the amount of change is the same. The two constitute a Wheatstone bridge.
The MEMS sensor according to claim 1, wherein in the initial position, the center plane of the magnet is coplanar with the center plane of the free magnetic layer in the magnetoresistance.
The MEMS sensor according to claim 2, wherein a support layer is further provided between the lower surface of the magnetoresistance and the sensitive film layer.
The MEMS sensor according to claim 1, wherein there are multiple magnetoresistances on opposite sides of the magnet, and the number of magnetoresistances on both sides and the distance from the magnet are in one-to-one correspondence.
The MEMS sensor according to claim 1, wherein at least two magnetic detection mechanisms are provided, which are respectively distributed on two opposite sides of the sensitive film layer.
The MEMS sensor according to claim 1, wherein a first cantilever beam extends outwards from two opposite sides of the sensitive part, and the magnetic detection mechanism is arranged on the first cantilever beam and the fixed part.
The MEMS sensor according to claim 1, wherein a first cantilever beam extends outwards on opposite sides of the sensitive part, and a second cantilever beam is provided at a free end of the first cantilever beam; the magnetic The detection mechanism is arranged on the second cantilever beam and the fixed part.
The MEMS sensor according to claim 6 or 7, characterized in that it further comprises a pre-bending mechanism, the pre-bending mechanism comprises a cantilever part separated from the sensitive part and the fixed part on the sensitive film layer, and the cantilever part is provided with a change The free end and the sensitive part are located between the stress layer in the Z-axis direction; an electrostatic force for adjusting the position of the sensitive part is applied between the cantilever part and the sensitive part.
The MEMS sensor according to claim 1, wherein the sensitive part is suspended in the back cavity of the substrate, and one side of the sensitive part is fixed on the substrate; the magnetic detection mechanism is distributed away from the sensitive part and the substrate. Fixed position at the bottom.
The MEMS sensor according to claim 1, wherein the sensitive part is suspended in the back cavity of the substrate, and its opposite sides are respectively fixed on the substrate; the magnetic detection mechanism is distributed on the sensitive part In the middle of the location.
The MEMS sensor according to any one of claims 1 to 10, wherein the MEMS sensor is a MEMS pressure sensor, a MEMS gas sensor, a MEMS microphone, a MEMS temperature sensor, a MEMS humidity sensor or a MEMS displacement sensor.
An electronic device, characterized by comprising the MEMS sensor according to any one of claims 1 to 11.