WO2020133253A1 - Detection membrane body, sensor, and electronic device - Google Patents

Abstract

A detection membrane body (100), comprising the following parts located on the same membrane surface: a frame body part (1); a membrane body part, which is connected to the frame body part (1) and configured to be deformed in a direction perpendicular to the membrane surface when an external force is exerted to the membrane body part; a fixed part, which is connected to the frame body part (1); and a movable part, which is configured to be driven to rotate in the membrane surface when the membrane body part is deformed, so as to approach or leave away from the fixed part, wherein a detection mechanism is disposed on the fixed part and the movable part for outputting an electric signal representing the rotation of the movable part. The detection membrane body (100) is no longer limited by air resistance, rear cavity volume, and the like, and the process is easy to realize.

Description

Detection of membranes, sensors and electronic equipment Technical field

The present invention relates to the field of energy conversion, and more specifically, to a detection membrane body; the invention also relates to a sensor using the detection membrane body, and an electronic device using the sensor.

Background technique

Existing mainstream sensors, such as microphones, pressure sensors, displacement sensors, etc., are detected by the principle of plate capacitors. For example, in the structure of a microphone, it usually includes a substrate, a back plate and a diaphragm formed on the substrate, wherein 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.

In order to make full use of the mechanical sensitivity of the diaphragm, the microphone needs to design a huge back cavity with ambient pressure to ensure that the rigidity of the flowing air far exceeds the diaphragm. The volume of the rear cavity is usually much larger than 1 mm ³ , for example, the volume of the rear cavity is usually designed to be 1-15 mm ³ . And when the microphone chip is packaged, it needs to open its cavity. This limits the design of the smallest size package of MEMS microphones (>3mm ³ ).

At this time, if the volume of the back cavity of the microphone is too small, it is very unfavorable for the circulation of air. The rigidity of this air will greatly reduce the mechanical sensitivity of the diaphragm. In addition, in order to balance the pressure in the back cavity, dense via holes are usually designed on the back plate, and the gap or the air flow resistance in the perforation caused by the viscosity of the air becomes the dominant factor of MEMS microphone noise, which will To a certain extent limits the high signal-to-noise ratio performance of the microphone, which ultimately leads to poor performance of the microphone. In addition, in order to make the diaphragm resistant to external pressure, it is required that the diaphragm has better rigidity, so that it can withstand greater external pressure, but this will cause the mechanical sensitivity of the diaphragm to be greatly reduced, resulting in an open circuit of the microphone The relatively low sensitivity will eventually affect the performance of the microphone.

For the traditional magnetic sensor structure without a backplane, the magnetic sensor and the magnet are placed on a relatively moving plane, and the sound pressure will deform the diaphragm out of the plane, thereby changing the gap between the GMR and the magnet. The sensor of this structure needs to accurately control the gap of the rest position. For a spatial sensitivity (gradient) of a magnet greater than 2E5T/m, a control accuracy of less than 2% is usually required, 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 detecting a membrane body.

According to the first aspect of the present invention, there is provided a detection membrane body, which includes:

Frame part;

A membrane body portion, the membrane body portion is connected to the frame body portion, and is configured to deform in a direction perpendicular to the membrane surface when subjected to an external force;

A fixing portion, the fixing portion is connected to the frame portion;

A movable portion, the movable portion is configured to drive the rotation of the movable portion within the membrane surface when the membrane body portion is deformed to approach or move away from the fixed portion;

Wherein, a detection mechanism is provided on the fixed part and the movable part for outputting an electrical signal characterizing the rotation of the movable part.

Optionally, one side of the membrane body part is connected to the frame body part; the movable part includes a cantilever beam part, and the cantilever beam part is connected to the other side of the membrane body part through a connection part connection.

Optionally, there are two membrane body parts, which are respectively denoted as a symmetrically arranged first membrane body part and second membrane body part; the outer sides of the first membrane body part and the second membrane body part are connected to the The frame body portion; the cantilever beam portion is suspended relative to the frame body portion, and is located between the first membrane body portion and the second membrane body portion; the first membrane body portion is connected to the cantilever through the first connection portion The beam portion is connected, the second membrane body portion is connected to the cantilever beam portion through a second connection portion, and the first connection portion and the second connection portion are staggered from each other.

Optionally, the movable portion further includes a bearing portion provided at both ends of the cantilever beam portion, and the detection mechanism is provided on the bearing portion and the fixed portion.

Optionally, the detection mechanism includes a magnetic sensor provided on one of the carrying part and the fixing part, and a magnet provided on the other one of the carrying part and the fixing part.

Optionally, each magnetic sensor cooperates with a magnet to form a detection mechanism.

Optionally, each magnetic sensor corresponds to two magnets, denoted as a first magnet and a second magnet, respectively. The magnetic sensor is disposed in a common magnetic field formed by the first magnet and the second magnet; at the initial position, the magnetic sensor is located The magnetic field direction of the first magnet is opposite to the magnetic field direction of the second magnet; the magnetic sensor constitutes a detection mechanism with the first magnet and the second magnet, and is configured to sense the first magnet, The second magnet outputs a changed electrical signal in response to a change in the magnetic field.

Optionally, the first magnet and the second magnet are sequentially and horizontally arranged on the carrying part in the same magnetic pole direction, and the magnetic sensor is provided on the fixing part at a position corresponding to the first magnet and the second magnet;

Alternatively, the first magnet and the second magnet are sequentially arranged horizontally on the fixed portion in the same magnetic pole direction, and the magnetic sensor is provided on the bearing portion at a position corresponding to the first magnet and the second magnet.

Optionally, each carrying part corresponds to two fixing parts, which are respectively denoted as a first fixing part and a second fixing part; the first fixing part and the second fixing part are distributed on opposite sides in the rotation direction of the bearing part;

The magnetic sensor is arranged on the bearing part, the first magnet and the second magnet are respectively arranged on the first fixing part and the second fixing part on both sides of the bearing part, and the first magnet and the second magnet are oriented in the magnetic pole direction Arrange in the opposite way.

Optionally, at the initial position, the magnetic sensor receives the magnetic field of the first magnet, which is equal in magnitude to the magnetic field of the second magnet, and the direction is opposite.

Optionally, the magnet and the magnetic sensor are formed on the carrying part and the fixing part through a MEMS process.

Optionally, the magnetic sensor is an AMR sensor, GRM sensor or TMR sensor.

Optionally, each bearing portion corresponds to two fixing portions, which are respectively denoted as a first fixing portion and a second fixing portion; the first fixing portion and the second fixing portion are distributed on both sides in the rotation direction of the bearing portion;

The detection mechanism includes a magnet provided on the bearing part, and a first magnetic sensor and a second magnetic sensor respectively provided on the first fixing part and the second fixing part; the first magnetic sensor and the magnet constitute a first detection mechanism The second magnetic sensor and the magnet constitute a second detection mechanism; the first detection mechanism and the second detection mechanism constitute a differential detection mechanism.

Optionally, the detection film body is formed by a MEMS process, and the frame portion, the film body portion, the fixed portion, and the movable portion are formed by a gap provided in the detection film body.

Optionally, the gap is acoustically sealed.

Optionally, the membrane body portion, the fixed portion, and the movable portion have deformation compliance in the membrane surface after being pressed.

According to another aspect of the present invention, there is also provided a sensor including a substrate and the above-mentioned detection film body disposed on the substrate.

Optionally, the substrate has a back cavity, the frame portion of the detection membrane body is fixed on the substrate, and the position of the detection membrane body except the frame portion is suspended relative to the substrate.

Optionally, the detection membrane body is supported on the substrate by a support portion, and forms a cavity with the substrate.

Optionally, the sensor is a microphone, and the detection membrane is configured to deform under the effect of sound pressure.

Optionally, the sensor is a displacement sensor, and further includes a conduction device that drives and detects the deformation of the film body.

Optionally, it further includes a sensitive film that is disposed on the substrate and is sensitive to the environment; the sensitive film and the substrate surround a vacuum chamber; and the detection film body is disposed in the vacuum chamber and is in contact with the sensitive film Relative setting; also includes a conductive device for transmitting the deformation of the sensitive membrane to the detection membrane body.

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

According to a detection membrane body of the present disclosure, the movable portion is displaced in the membrane surface, and the detection mechanism is disposed in the membrane surface, which is no longer limited by air resistance, rear cavity volume, etc. , And the process is also easy to implement.

Other features and advantages of the present invention will become clear by the following detailed description of exemplary embodiments of the present invention with reference to the drawings.

BRIEF DESCRIPTION

The drawings incorporated in and forming a part of the specification illustrate embodiments of the invention, and together with the description thereof, serve to explain the principles of the invention.

FIG. 1 is a schematic diagram of the structure of the detection membrane of the present invention.

Fig. 2 is an equivalent schematic diagram of the movement of the fixed part and the movable part.

Fig. 3 is a schematic diagram of the first embodiment of the dual magnet structure of the present invention.

4 is a schematic diagram of a second embodiment of the dual magnet structure of the present invention.

FIG. 5 is a schematic structural view of the first embodiment of the sensor of the present invention.

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

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

detailed description

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

The following description of at least one exemplary embodiment is actually merely illustrative, and in no way serves as any limitation on the invention and its application or use.

Techniques, methods and equipment known to those of ordinary skill in the related art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the specification.

In all examples shown and discussed herein, any specific values should be interpreted as merely exemplary and not 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, therefore, once an item is defined in one drawing, there is no need to discuss it further in subsequent drawings.

The invention provides a detection membrane body with a detection mechanism formed in the membrane surface. When the detection membrane body is deformed by an external force, the detection mechanism in the membrane surface can output a changed electrical signal. For example, when the detection membrane is subjected to sound pressure or other forms of pressure, the detection membrane will be deformed in a direction perpendicular to the membrane surface, so that the detection mechanism in the membrane surface outputs a varying electrical signal to characterize the detection The degree of membrane deformation.

The entire detection membrane body of the present invention includes a frame portion, a membrane body portion, a fixed portion, and a movable portion located in the same membrane surface. The same film surface refers to the entire surface of the detection film body, which may be a flat surface or a curved surface. The frame part, the film body part, the fixed part, and the movable part are all located in the film surface of the detection film body.

The frame body portion is located on the outer side, and it may be a circular frame or a rectangular frame, which plays a role of carrying and fixing. For example, in specific applications, the frame portion can be connected to the substrate to support the detection membrane on the substrate.

The membrane body portion is located in the frame body portion and is connected to the frame body portion. The membrane body portion is the main area for detecting compression deformation of the membrane body. For example, when the external sound pressure acts vertically on the membrane body, the membrane body will bend and deform in a direction perpendicular to the membrane surface. This deformation is similar to the deformation of a diaphragm in a conventional microphone.

The fixed part and the movable part are configured to provide a detection mechanism that outputs an electrical signal. The detection mechanism may be, for example, a magnetic detection mechanism. Of course, if the process permits, other types of detection mechanisms well known to those skilled in the art may also be used, such as a capacitive type and a transistor type. A part of the detection mechanism may be provided on the fixed part, and the other part may be provided on the movable part. When the movable part is displaced relative to the fixed part, the detection mechanism detects the displacement and outputs a changed electrical signal.

The fixed part and the movable part are both located in the frame body part, and the fixed part is connected to the frame body part, and the movable part is displaced relative to the fixed part under the action of the deformation of the membrane body part. In the present invention, the movable portion is configured such that when the membrane body portion is deformed perpendicular to the membrane surface, the membrane body portion drives the rotation of the movable portion within the membrane surface to approach or move away from the fixed portion.

In other words, the displacement of the movable portion is located in the film surface of the detection film body and does not deviate from the film surface. In the XYZ three-axis coordinate system, assuming that the film surface is in the XY plane, the movable part rotates in the XY plane. Because the deformation of the membrane body is approximately perpendicular to the membrane surface, that is, in the Z direction. Therefore, a direction changing structure needs to be provided between the film body portion and the movable portion to convert the deformation in the Z direction into motion in the XY plane.

Such a direction changing structure may adopt a structure well-known in the prior art, for example, a design structure that can be used in a gyroscope or an accelerometer to change the direction. The specific structure of the detection membrane of the present invention will be described in detail below in conjunction with specific embodiments.

Referring to FIG. 1, the detection membrane body 100 of the present invention includes a rectangular frame portion 1 on the outer side, the membrane body portion is disposed in the frame body portion 1, and one side of the membrane body portion is connected to the frame body portion 1. Two membrane body parts are provided, which are denoted as the first membrane body part 2 and the second membrane body part 3, respectively. The first membrane body portion 2 and the second membrane body portion 3 are symmetrically distributed along the axis of the detection membrane body 100, and are respectively connected to opposite sides of the frame body portion 1.

A gap is formed between the first film body portion 2 and the second film body portion 3, the movable portion is located in the gap, and is suspended in the frame body portion 1. That is, the movable part is suspended between the first membrane body 2 and the second membrane body 3. Specifically, the movable portion includes a cantilever beam portion 4, and the cantilever beam portion 4 may have an elongated shape, which extends in a gap between the first membrane body portion 2 and the second membrane body portion 3.

The first membrane body portion 2 is connected to the cantilever beam portion 4 through the first connection portion 11, the second membrane body portion 3 is connected to the cantilever beam portion 4 through the second connection portion 12, and the first connection portion 11 and the second connection portion 12 Staggered from each other, the cantilever beam portion 4 is supported between the first membrane body portion 2 and the second membrane body portion 3 only through the first connection portion 11 and the second connection portion 12.

When the first membrane body portion 2 and the second membrane body portion 3 are deformed by compression, the first membrane body portion 2 generates a tensile force on the cantilever beam portion 4 through the first connection portion 11, and the second membrane body portion 3 is connected through the second connection The portion 12 generates tension on the cantilever beam portion 4. The first connection portion 11 and the second connection portion 12 are located on both sides of the cantilever beam portion 4 and pull the cantilever beam portion 4 in opposite directions, respectively. And the first connection portion 11 and the second connection portion 12 are staggered from each other, and finally the cantilever beam portion 4 rotates in the film surface.

FIG. 2 shows an equivalent schematic view of the rotation of the cantilever beam portion 4. Referring to FIGS. 1 and 2, when the detection membrane body receives pressure from a direction perpendicular to the membrane surface, such as sound pressure. The first membrane body 2 and the second membrane body 3 are deformed perpendicular to the direction of the membrane surface. At this time, the first membrane body 2 and the second membrane body 3 pass through the first connecting portion 11 and the second connecting portion 12, respectively Tensile stress is generated on both sides of the cantilever beam portion 4. In addition, the tensile stress generated by the first connecting portion 11 on the cantilever beam portion 4 is opposite to the tensile stress generated on the cantilever beam portion 4 by the second connecting portion 12, and finally the cantilever beam portion 4 rotates.

The cantilever beam portion 4 is located between the first membrane body portion 2 and the second membrane body portion 3. When the cantilever beam portion 4, the first membrane body portion 2, and the second membrane body portion 3 are subjected to pressure such as sound pressure, the whole Displacement occurs in the direction perpendicular to the membrane surface. The rotation of the cantilever beam portion 4 under the action of the first connection portion 11 and the second connection portion 12 also occurs in the film surface of the detection film body, and does not deviate from the film surface of the detection film body.

Optionally, the membrane body part, the fixed part, and the movable part have deformation compliance in the membrane surface after being pressed. In other words, according to the different positions of the membrane body, the fixed part, and the movable part in the membrane surface, after being simultaneously pressed, their response to pressure conforms to the deformation posture of the complete membrane surface at different positions. For example, the degree of deformation in the middle area of the membrane surface is large, and the degree of deformation in the edge area of the membrane surface is relatively small. The deformation of the middle area of the membrane surface is approximately in a translational state, and the deformation of the edge of the membrane surface is approximately inclined due to the proximity to the frame body.

A part of the detection mechanism of the present invention may be provided on the cantilever beam portion 4, for example, at the end of the cantilever beam portion 4. In view of the consideration of the occupied area of the detection mechanism and the size of the cantilever beam itself, the movable portion of the present invention further includes a bearing portion provided on the cantilever beam. A part of the detection mechanism may be formed on the carrying part.

Referring to FIG. 1, two bearing portions may be provided, which are located at opposite ends of the cantilever beam portion 4 respectively, and the two bearing portions are denoted as a first bearing portion 5 and a second bearing portion 6, respectively. The fixing portion is located in the rotation direction of the bearing portion, and one side thereof is connected to the frame body portion 1. Four fixing portions of the present invention may be provided, which are denoted as a first fixing portion 7, a second fixing portion 8, a third fixing portion 9, and a fourth fixing portion 10, respectively. Wherein, the first fixing portion 7 and the second fixing portion 8 are respectively located on opposite sides of the first bearing portion 5 in the rotation direction, and the third fixing portion 9 and the fourth fixing portion 10 are respectively located opposite in the rotation direction of the second bearing portion 6 On both sides.

When the cantilever beam portion 4 and the first bearing portion 5 rotate, for example, when the first bearing portion 5 moves in the direction of the first fixing portion 7 in the film surface, the distance between the first bearing portion 5 and the first fixing portion 7 changes If it is small, the distance between the first bearing portion 5 and the second fixing portion 8 becomes larger. Therefore, a detection mechanism may be provided between the first bearing portion 5 and the first fixing portion 7, and another detection mechanism may be provided between the first bearing portion 5 and the second fixing portion 8. The two detection mechanisms constitute a differential detection mechanism .

Based on the same principle, the two detection mechanisms formed between the second bearing portion 6 and the third fixing portion 9 and the fourth fixing portion 10 may also constitute a differential detection mechanism. In addition, since the first bearing portion 5 and the second bearing portion 6 are located at opposite ends of the cantilever beam portion 4, respectively, a differential detection mechanism may be formed between the two.

These detection mechanisms can output changing electrical signals to express the degree of rotation of the bearing portion relative to the fixed portion, the deformation posture of the membrane body portion, and the pressure information of the membrane body portion, thus the change information of the outside world can be obtained through the detection mechanism .

The detection film body of the present invention can be formed by a MEMS process. When the detection film body is separately manufactured, for example, it can be formed by processes such as layer-by-layer deposition and etching. It is also possible to form a detection film body on the substrate or other substrates through layer-by-layer deposition, etching and other processes when manufacturing a specific sensor.

In order to ensure that all components are within the film surface of the detection film body, the frame portion 1, the film body portion, the fixed portion, and the movable portion of the present invention are formed by the slit 15 provided in the detection film body. That is, by performing photolithography on the complete detection film body or other methods well known to those skilled in the art, a gap 15 is formed on the detection film body, so that the first film body of the present invention is formed on the detection film body through the gap 15 Part 2, second membrane body part 3, cantilever beam part 4, first connection part 11, second connection part 12, first bearing part 5, second bearing part 6, first fixing part 7, second fixing part 8 , The third fixing portion 9, the fourth fixing portion 10 and other components.

When the detection membrane of the present invention is applied to the sound pressure detection in the microphone, part of the sound pressure will pass through the gap 15, which may affect the detection performance of the detection membrane. In an alternative embodiment of the present invention, the gap 15 is acoustically sealed, ie, sound waves will not pass through the gap 15. The width dimension of the slit 15 may be less than 1 μm, for example, and may be less than 0.5 μm. It should be noted here that the acoustic seal does not limit the complete sealing of the acoustic wave, it is the sealing of the acoustic wave within the error range or on the premise of not affecting the use of the microphone.

The detection mechanism of the present invention may use a magnetic detection mechanism, which includes a magnet and a magnetic sensor for cooperating with the magnet. Through the change of the distance between the magnetic sensor and the magnet, the magnetic sensor can output a changed electrical signal. For the magnetic sensor, for example, a giant magnetoresistive sensor (GMR), a tunnel magnetoresistive sensor (TMR), or an anisotropic magnetoresistive sensor (AMR) can be selected. By using a highly sensitive giant magnetoresistive sensor (GMR), tunnel magnetoresistive sensor (TMR) or anisotropic magnetoresistive sensor (AMR) to obtain the detected electrical signal, the electrical performance of the detection mechanism can be guaranteed.

The magnet and the magnetic sensor can be formed on the corresponding positions of the detection film body through the MEMS process. The magnet may be a deposited magnetic thin film. The magnetic film can be directly made of magnetic material, or it can be magnetized after the film is formed. The magnetic thin film can be made of CoCrPt or CoPt, which will not be described in detail here.

For example, in one embodiment of the present invention, the detection mechanism includes a magnetic sensor 13 provided on one of the carrying part and the fixing part, and a magnet 14 provided on the other of the carrying part and the fixing part.

Specifically, the magnet 14 may be disposed on the bearing portion, and the magnetic sensor 13 is disposed on the fixed portion, and the wiring of the magnetic sensor may be directly led out through the fixed portion and the frame portion. When the bearing portion approaches the fixed portion, the magnetic sensor 13 will output a varying electrical signal. This detection principle belongs to the common knowledge of those skilled in the art and will not be described in detail here.

Of course, it is also possible to arrange the magnet 14 on the fixed part and the magnetic sensor 13 on the carrying part. In this case, the leads of the magnetic sensor 13 need to pass through the carrying part, the cantilever beam part, the first or second connecting part, and the membrane body part 3. The frame part is drawn out and will not be described in detail here.

The detection mechanism of the present invention may be a magnetic sensor cooperated with a magnet to form a detection mechanism. Referring to FIG. 1, for example, a first magnetic sensor may be provided on the first fixing portion 7, a second magnetic sensor may be provided on the second fixing portion 8, and a magnet may be provided on the first bearing portion 5. The first magnetic sensor and the magnet constitute a first detection mechanism; the second magnetic sensor and the magnet constitute a second detection mechanism. The first detection mechanism and the second detection mechanism constitute a differential detection mechanism.

When choosing to place the magnets on the first fixing portion 7 and the second fixing portion 8 respectively, two magnetic sensors on the first bearing portion 5 need to be provided to connect with the first fixing portion 7 and the second fixing portion 8 respectively Of the magnets.

The fitting structure between the second bearing portion 6, the third fixing portion 9, and the fourth fixing portion 10 is the same as the fitting structure between the first bearing portion 5, the first fixing portion 7, and the second fixing portion 8. Let me explain in more detail.

In another embodiment of the present invention, each magnetic sensor corresponds to two magnets:

Each detection mechanism includes a first magnet, a second magnet, and a magnetic sensor disposed in the first magnet and the second magnet forming a common magnetic field. The first magnet and the second magnet are arranged together so that the magnetic fields of the two interact with each other. The magnetic sensor simultaneously senses the magnetic field of the first magnet and the second magnet, so that the magnetic sensor can sense the change of the common magnetic field of the first magnet and the second magnet, thereby outputting a changed electrical signal.

In the common magnetic field of the first magnet and the second magnet, at certain positions, the magnetic fields of the two magnets are in opposite directions. At this position, the common magnetic field of the two magnets received by the magnetic sensor is weakened compared to a single magnet. The initial position of the magnetic sensor is at a position where the magnetic field of the first magnet is opposite to the magnetic field of the second magnet.

Preferably, in the initial position, the magnetic sensor receives the magnetic field of the first magnet and has the same magnitude as the magnetic field of the second magnet and the opposite direction. That is to say, at this position, the magnetic sensor receives the same magnitude of the magnetic field of the two magnets and the direction is opposite. At this time, the common magnetic field of the two magnets received by the magnetic sensor is zero.

In the dual-magnet embodiment illustrated in FIG. 3, the magnetic sensor 130 is disposed on the first fixing portion 7, and the first magnet 140 and the second magnet 141 are disposed adjacent to the first bearing portion 5 and have the same magnetic pole direction The methods are arranged horizontally in sequence. For example, at the time of manufacture, two independent thin films are first formed on the first bearing part 5, and then the two thin films are simultaneously magnetized. After magnetization, referring to the view direction of FIG. 3, the left side of the first magnet 140 and the second magnet 141 are both N poles and the right side are S poles; vice versa.

The magnetic sensor 130 is provided corresponding to the first magnet 140 and the second magnet 141. When the first carrying part 5 moves in the direction of the first fixing part 7, the magnetic sensor 130 can sense the change of the common magnetic field of the first magnet 140 and the second magnet 141 at this time, thereby outputting the changed electrical signal.

The magnetic sensor 130 may be disposed on one side of the center line of the first magnet 140 and the second magnet 141. When both the left side of the first magnet 140 and the second magnet 141 are N poles and the right side are both S poles, the magnetic field directions of the first magnet 140 and the second magnet 141 both return from the N pole to the S pole. Therefore, at a position above the center lines of the first magnet 140 and the second magnet 141, the magnetic field directions of the first magnet 140 and the second magnet 141 are opposite, and the magnetic field strengths are approximately the same. This position is the initial position of the magnetic sensor 130.

The magnetic sensor 130 will be relatively close to or away from the magnet at this initial position. Since the magnetic sensor 130 is affected by two magnets at the same time, the two magnets work together to reduce the strength of the entire magnetic field, and improve the sensitivity of the magnetic field change within the linear range of the magnetic sensor 130, and ultimately improve the magnetic sensor 130's Detection sensitivity.

In this embodiment, the magnetic sensor 130 on the first fixing portion, the first magnet 140 and the second magnet 141 on the first carrying portion constitute a detection mechanism.

Another magnetic sensor may be provided on the second fixing part, and the magnetic sensor may form another detection mechanism with the first magnet 140 and the second magnet 141 on the first carrier part. These two detection mechanisms may constitute a differential detection mechanism, which will not be described in detail here. In addition, the fitting structure between the second bearing portion, the third fixing portion, and the fourth fixing portion is the same as the fitting structure between the first bearing portion, the first fixing portion, and the second fixing portion, and will not be described in detail here.

In the dual-magnet embodiment illustrated in FIG. 4, the magnetic sensor 130 is disposed on the first bearing portion 5, and the first magnet 140 and the second magnet 141 are disposed on the first fixing portion 7 and the second fixing portion 8, respectively. The first magnet 140 and the second magnet 141 are arranged in such a manner that the magnetic pole directions are opposite. 4, when the left side of the first magnet 140 is S pole and the right side is N pole, the left side of the second magnet 141 is N pole and the right side is S pole; vice versa.

The magnetic field directions of the first magnet 140 and the second magnet 141 both return from the N pole to the S pole. In this arrangement, at the center of the first magnet 140 and the second magnet 140, the magnetic field directions of the first magnet 140 and the second magnet 141 are opposite, and the magnetic field strengths are approximately the same.

When the magnetic sensor 130 rotates with the first bearing portion, the magnetic sensor 130 will move toward the first magnet 140 or the second magnet 141 with the central position as the initial position. At this initial position, the magnetic sensor 130 receives the same magnetic field from the two magnets and the directions are opposite. For example, when the magnetic sensor 130 is close to the first magnet 140 and away from the second magnet 141, it can be known from the characteristics of the magnet that the magnetic sensor 130 is more affected by the first magnet 140 than it is by the second magnet 141; and vice versa.

Since the magnetic sensor 130 is affected by two magnets at the same time, the two magnets work together to reduce the strength of the entire magnetic field, and improve the sensitivity of the magnetic field change within the linear range of the magnetic sensor 130, and ultimately improve the magnetic sensor 130's Detection sensitivity.

The matching structure between the second bearing portion, the third fixing portion, and the fourth fixing portion is the same as the matching structure between the first bearing portion, the first fixing portion, and the second fixing portion, and will not be described in detail here.

The detection membrane of the present invention can be applied to various sensors, such as microphones, or environmental sensors such as pressure, gas, temperature, and humidity detection, and can also be applied to displacement sensors.

FIG. 5 shows an embodiment of the sensor of the present invention. The sensor includes a substrate 101a and a detection film body 100a disposed on the substrate 101a. The detection film body 100a may be supported on a layer 103a of the substrate 101a by a support portion 104a Above, other design structures need to be determined according to the type of sensor. For example, when the sensor is a microphone structure, the substrate 101a has a rear cavity 102a, and the frame portion of the detection membrane body 100a is fixed to the substrate 101a through the support portion 104a, so that the position of the detection membrane body 100a except the frame portion relative to the substrate The bottom 101a is suspended.

The detection membrane body 100a directly communicates with the back cavity of the substrate 101a. Compared with the flat capacitor formed by the traditional back plate and diaphragm, the structure of the air gap makes the detection membrane body 100a no longer suffer from acoustic resistance. limit.

For example, when the sensor is a displacement sensor, it also includes a conduction device that drives the detection of the deformation of the membrane body 100a. The conduction device may be a rod or the like. The moving member of the displacement sensor transmits the displacement to the detection membrane body 100a through the rod. No specific explanation.

FIG. 6 shows another embodiment of the sensor of the present invention. The sensor includes a substrate 101b and a detection film body 100b disposed on the substrate 101b. The detection film body 100b may be supported on a layer of the substrate 101b by a support portion 104b A cavity 102b is formed on the substrate 103b and surrounds the substrate 101b.

FIG. 7 shows another embodiment of the sensor of the present invention. For those skilled in the art, some sensors require a vacuum chamber structure during operation. In order to solve this problem, the sensor provided in this embodiment includes a substrate 101c and a sensitive film 106c disposed on the substrate 101c. The sensitive film 106c may be a sensitive film sensitive to environmental information such as gas, pressure, and temperature. The sensitive film 106c is supported on the substrate 101c and forms a vacuum chamber 102c with the substrate 101c. The detection membrane body 100c is disposed in the vacuum chamber 102c and is disposed opposite to the sensitive membrane 106c.

Specifically, the detection film body 100c is supported on the layer 103c of the substrate 101c through the first support portion 104c, and the sensitive film 106c is supported on the detection film body 100c through the second support portion 105c, for example, on the frame of the detection film body 100c On the body, the sensitive film 106c, the support, and the substrate 101c form a vacuum chamber.

A conductive device 107c is also provided between the sensitive film 106c and the detection film body 100c. The conductive device 107c may be a rod or a pillar to transmit the deformation of the sensitive film 106c to the detection film body 100c to make the detection film body 100c emits a varying electrical signal.

The invention also provides an electronic device including the sensor described above. The electronic device may be a mobile phone, a tablet computer, or other smart devices known to those skilled in the art.

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, 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 (23)

1. A detection membrane body, characterized in that it includes: located in the same membrane surface:

   Frame part;

   A membrane body portion, the membrane body portion is connected to the frame body portion, and is configured to deform in a direction perpendicular to the membrane surface when subjected to an external force;

   A fixing portion, the fixing portion is connected to the frame portion;

   A movable portion, the movable portion is configured to drive the rotation of the movable portion within the membrane surface when the membrane body portion is deformed to approach or move away from the fixed portion;

   Wherein, a detection mechanism is provided on the fixed part and the movable part for outputting an electrical signal characterizing the rotation of the movable part.
2. The detection membrane body according to claim 1, wherein one side of the membrane body portion is connected to the frame portion; the movable portion includes a cantilever beam portion, and the cantilever beam portion is connected by The part is connected to the other side of the membrane body part.
3. The detection membrane body according to claim 2, characterized in that the membrane body portion is provided with two pieces, which are denoted as a symmetrically arranged first membrane body portion and second membrane body portion; the first membrane body portion 2. The outer side of the second film body is connected to the frame body; the cantilever beam is suspended relative to the frame body and is located between the first film body and the second film body; the first film The body portion is connected to the cantilever beam portion through a first connection portion, the second membrane body portion is connected to the cantilever beam portion through a second connection portion, and the first connection portion and the second connection portion are offset from each other.
4. The detection film body according to claim 3, wherein the movable portion further includes a bearing portion provided at both ends of the cantilever beam portion, and the detection mechanism is provided on the bearing portion and the fixed portion.
5. The detection film body according to claim 4, wherein the detection mechanism includes a magnetic sensor provided on one of the bearing part and the fixing part, and a magnet provided on the other of the bearing part and the fixing part.
6. The detection film body according to claim 5, wherein each magnetic sensor cooperates with a magnet to form a detection mechanism.
7. The detection film body according to claim 5, wherein each magnetic sensor corresponds to two magnets, which are respectively denoted as a first magnet and a second magnet, and the magnetic sensor is disposed in a common magnetic field formed by the first magnet and the second magnet In the initial position, the magnetic sensor is located at a position where the magnetic field direction of the first magnet is opposite to the magnetic field direction of the second magnet; the magnetic sensor forms a detection mechanism with the first magnet and the second magnet, and is configured to During the rotation of the bearing portion, a change in the common magnetic field of the first magnet and the second magnet is induced to output a changed electrical signal.
8. The microphone according to claim 7, wherein the first magnet and the second magnet are sequentially arranged horizontally on the carrying portion in the same magnetic pole direction, and the magnetic sensor is disposed on the fixing portion with the first magnet, The position corresponding to the second magnet;

   Alternatively, the first magnet and the second magnet are sequentially arranged horizontally on the fixed portion in the same magnetic pole direction, and the magnetic sensor is provided on the bearing portion at a position corresponding to the first magnet and the second magnet.
9. The microphone according to claim 7, wherein each carrying portion corresponds to two fixing portions, which are respectively denoted as a first fixing portion and a second fixing portion; the first fixing portion and the second fixing portion are distributed on the bearing Opposite sides in the direction of rotation;

   The magnetic sensor is arranged on the bearing part, the first magnet and the second magnet are respectively arranged on the first fixing part and the second fixing part on both sides of the bearing part, and the first magnet and the second magnet are oriented in the magnetic pole direction Arrange in the opposite way.
10. The microphone according to claim 7, wherein at the initial position, the magnetic sensor receives the magnetic field of the first magnet and the magnetic field of the second magnet is equal in magnitude and opposite in direction.
11. The detection film body according to claim 5, wherein the magnet and the magnetic sensor are formed on the carrying part and the fixing part by a MEMS process.
12. The detection film body according to claim 5, wherein the magnetic sensor is an AMR sensor, a GRM sensor or a TMR sensor.
13. The detection film body according to claim 5, wherein each carrying part corresponds to two fixing parts, which are respectively denoted as a first fixing part and a second fixing part; the first fixing part and the second fixing part are arranged On both sides in the direction of rotation of the bearing part;

    The detection mechanism includes a magnet provided on the bearing portion, and a first magnetic sensor and a second magnetic sensor respectively provided on the first fixing portion and the second fixing portion; the first magnetic sensor and the magnet constitute a first detection mechanism The second magnetic sensor and the magnet constitute a second detection mechanism; the first detection mechanism and the second detection mechanism constitute a differential detection mechanism.
14. The detection membrane body according to any one of claims 1 to 13, wherein the detection membrane body is formed by a MEMS process, and the frame portion, the film body portion, the fixed portion, and the movable portion pass through the detection membrane body The gap formed on the top is formed.
15. The detection membrane body according to claim 14, wherein the gap is acoustically sealed.
16. The detection membrane body according to claim 14, wherein the membrane body portion, the fixed portion, and the movable portion have deformation compliance in the membrane surface after being pressed.
17. A sensor characterized by comprising a substrate and the detection film body according to any one of claims 1 to 16 provided on the substrate.
18. The sensor according to claim 17, wherein the substrate has a back cavity, the frame portion of the detection membrane body is fixed on the substrate, and the position of the detection membrane body except the frame portion is relative to the substrate The bottom is hanging.
19. The sensor according to claim 17, wherein the detection film body is supported on the substrate by a support portion, and surrounds the substrate with a cavity.
20. The sensor according to any one of claims 17 to 19, wherein the sensor is a microphone, and the detection membrane is configured to deform under the effect of sound pressure.
21. The sensor according to any one of claims 17 to 19, wherein the sensor is a displacement sensor, and further includes a conduction device that drives and detects the deformation of the membrane body.
22. The sensor according to claim 17, further comprising a sensitive film provided on the substrate and sensitive to the environment; the sensitive film and the substrate enclose a vacuum chamber; and the detection film body is provided at The vacuum chamber is arranged opposite to the sensitive membrane; it also includes a conduction device for transmitting the deformation of the sensitive membrane to the detection membrane body.
23. An electronic device, characterized by comprising the sensor according to any one of claims 17 to 22.

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