MEMS sensor and electronic device

Abstract

The utility model provides an MEMS sensor and an electronic device, the MEMS sensor comprises a substrate, a groove arranged on the substrate, and an MEMS film arranged above the groove, the upper surface of the groove and the MEMS film form a parallel plate capacitor structure; an elastic connecting piece is arranged at the position where the substrate is connected with the MEMS membrane, and the two ends of the MEMS membrane are elastically connected with the substrate through the corresponding elastic connecting piece respectively; and the elastic connecting piece is used for assisting the MEMS membrane to elastically deform in the groove. According to the utility model, the deformation amount of the MEMS membrane can be expanded, and the damage of the MEMS membrane can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of sensor technology, and more specifically, to a MEMS sensor and electronic equipment. Background Art

[0002] With the progress of society and the development of technology, in recent years, the size of electronic products such as mobile phones, computers, and wearable devices has been continuously reduced, and people have higher and higher performance requirements for these portable electronic products, which also requires the size of the electronic parts that match them to be continuously reduced, and the performance and consistency to be continuously improved. MEMS products integrated by MEMS (Micro-Electro-Mechanical-System, referred to as MEMS) technology have begun to be applied in batches to such electronic products. Their packaging volume is smaller than that of traditional electronic devices, so they are favored by most microphone manufacturers.

[0003] The principle of existing capacitive MEMS pressure sensors is to convert the change in the spacing between the upper and lower capacitor plates into air pressure output, that is, to change the capacitance value by changing the position of the plates, and finally to detect the pressure. During the application process, the terminal client product will be cleaned after surface mounting to ensure the cleanliness of the mainboard circuit. The cleaning process is usually completed by adding a cleaning agent to the water and combining it with ultrasound to further remove organic compounds.

[0004] However, since pressure sensors are usually provided with air holes, liquid may enter the interior of the sensor during the cleaning process, and the foaming of the detergent may easily explode under the action of ultrasonic vibration. The explosion may generate a huge impact force on the MEMS membrane of the sensor, causing damage or rupture of the MEMS membrane, thereby affecting the performance of the sensor. Utility Model Content

[0005] In view of the above problems, the purpose of the present invention is to provide a MEMS sensor and an electronic device to solve the problems of signal crosstalk and product performance impact in existing products.

[0006] The MEMS sensor provided by the utility model comprises a substrate, a groove arranged on the substrate, and a MEMS membrane arranged above the groove, wherein the upper surface of the groove and the MEMS membrane form a parallel plate capacitor structure; an elastic connector is arranged at the position where the substrate and the MEMS membrane are connected, and the two ends of the MEMS membrane are elastically connected to the substrate through corresponding elastic connectors respectively; the elastic connector is used to assist the MEMS membrane to perform elastic deformation in the groove.

[0007] In addition, an optional structural feature is that the elastic connecting member is wavy or sawtooth-shaped; and the extension direction of the elastic connecting member is consistent with the setting direction of the MEMS membrane in a static state.

[0008] In addition, an optional structural feature is that the MEMS membrane is fixed between two elastic connecting members, and the two elastic connecting members are respectively fixedly connected to the substrate, so that the MEMS membrane is fixed on the substrate and covers the groove setting.

[0009] In addition, an optional structural feature is that the elastic connecting member and the base plate are an integrally formed structure.

[0010] In addition, an optional structural feature is that at least two vertically distributed limiting support structures are provided in the groove, and the height of the limiting support structure is adapted to the outer shape of the MEMS membrane in a state of maximum deformation.

[0011] In addition, an optional structural feature is that the limiting support structure is a limiting column or a limiting plate whose upper end surface is an arc-shaped structure.

[0012] In addition, an optional structural feature is that the limiting support structure and the base plate are an integrally formed structure.

[0013] In addition, an optional structural feature is that four grooves are arranged in the substrate at intervals, and a corresponding MEMS membrane is arranged on each groove through an elastic connector, and the four MEMS membranes form a capacitor bridge structure.

[0014] In addition, an optional structural feature is that the MEMS membrane is rectangular, circular or square.

[0015] On the other hand, the utility model also provides an electronic device, comprising the above-mentioned MEMS sensor.

[0016] By using the above-mentioned MEMS sensor and electronic device, elastic connectors are set at both ends of the MEMS membrane to elastically connect the MEMS membrane to the substrate, thereby increasing the deformation degree of the MEMS membrane, thereby preventing the MEMS membrane from breaking under special deformation conditions and improving the performance and stability of the sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] By referring to the following description in conjunction with the accompanying drawings, and with a more comprehensive understanding of the present invention, other purposes and results of the present invention will become more clear and easy to understand. In the accompanying drawings:

[0018] Figure 1 is a side view of a MEMS sensor according to an embodiment of the utility model;

[0019] Figure 2 FIG. 4 is a top view of a MEMS sensor according to an embodiment of the present utility model.

[0020] The reference numerals include: substrate 1 , limiting support structure 2 , elastic connecting member 3 , MEMS membrane 4 , groove 5 .

[0021] The same reference numerals throughout the drawings indicate similar or corresponding features or functions. DETAILED DESCRIPTION

[0022] In the following description, for the purpose of illustration, in order to provide a comprehensive understanding of one or more embodiments, many specific details are set forth. However, it is apparent that these embodiments may also be implemented without these specific details. In other examples, for ease of describing one or more embodiments, known structures and devices are shown in the form of block diagrams.

[0023] In the following description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0024] To solve the problem that in the existing MEMS sensor structure, the MEMS membrane is directly in contact with the substrate over a large area. When the MEMS membrane is overloaded, it can only be buffered by the cavity, which is very easy to break or deform, resulting in performance degradation or failure. Moreover, after the depth of the cavity and the thickness of the MEMS membrane are determined, the deformation ability of the MEMS membrane is also fixed, that is, the corresponding test range is also fixed, resulting in a small membrane deformation, affecting the test range, and not suitable for deep-sea diving application scenarios. The utility model provides a MEMS sensor and an electronic device, wherein elastic connectors are arranged at both ends of the MEMS membrane, and a limiting support structure is arranged at the bottom of the groove, which can increase the deformation of the MEMS membrane, expand the test direction, improve the performance and stability of the sensor, and improve the problem of failure after client cleaning.

[0025] In order to describe the MEMS sensor and electronic device of the present invention in detail, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0026] Figure 1 and Figure 2 The schematic structure of the MEMS sensor according to the embodiment of the utility model is shown from different angles respectively.

[0027] like Figure 1 and Figure 2As shown together, the MEMS sensor implemented by the utility model includes a substrate, a groove 5 arranged on the substrate 1, and a MEMS membrane 4 arranged above the groove 5, the upper surface of the groove 5 and the MEMS membrane 4 form a parallel plate capacitor structure, wherein the MEMS membrane 4 serves as an upper electrode and the upper surface of the groove 5 serves as a lower electrode. When the distance between the upper electrode and the lower electrode changes, the resistance value of the capacitor will change, thereby converting it into a related pressure signal output; in order to improve the deformation ability of the MEMS membrane 4 and prevent it from being easily broken due to direct connection with the substrate 1, elastic connectors 3 are respectively arranged at the positions where the substrate 1 and the MEMS membrane 4 are connected, so that the two ends of the MEMS membrane 4 are elastically connected to the substrate 1 through corresponding elastic connectors respectively, and during the MEMS deformation process, the elastic connector 3 can assist it in deforming in the groove 5.

[0028] Among them, the elastic connector 3 can adopt a spring-like structure or a wavy or sawtooth structure, which can undergo elastic deformation under the action of force and return to the initial position when the external force disappears. The elastic connector 3 in the utility model can be arranged at the two opposite ends of the substrate 1 to form a groove 5, and the extension direction of the elastic connector 3 is consistent with the setting direction of the MEMS membrane 4 in the static state, so that when the MEMS membrane 4 is deformed, its deformation amount can be further increased, thereby achieving the purpose of expanding the sensor test range.

[0029] As a specific example, the setting of the elastic connector 3 can be in two forms. First, the elastic connector 3 adopts an independent structure, one end of the elastic connector 3 is connected to the substrate 1, and the other end is connected to the MEMS membrane 4. During the assembly process, the MEMS membrane 4 and the elastic connector 3 can be assembled first, and then the overall structure formed by the MEMS membrane 4 and the elastic connector 3 and the substrate 1 are connected, so that the MEMS membrane 4 is fixed between the two elastic connectors 3, and the two elastic connectors 3 are respectively fixedly connected to the substrate 1 to ensure that the MEMS membrane 4 is fixed on the substrate 1 and covers the groove 5. Second, the elastic connector 3 and the substrate 1 adopt an integral molding structure, that is, the structure of the elastic connector is directly formed during the deposition, etching and other process treatments of the substrate 1, and its elastic connection function is realized through a wavy or zigzag structure.

[0030] Furthermore, while expanding the deformation of the MEMS membrane 4, in order to prevent the MEMS membrane 4 from breaking, at least two vertically distributed limiting support structures 2 can be set at the bottom of the groove 5, and the height of the limiting support structure 2 is adapted to the shape of the MEMS membrane 4 in the state of maximum deformation. Among them, the limiting support structure 2 can adopt a plurality of regularly distributed limiting columns, or a limiting plate structure with an arc-shaped structure on the upper end surface. The height of each limiting support structure 2 can be determined according to the position of the MEMS membrane 4 in the critical deformation state. The deformation limit of the MEMS membrane 4 is simulated by voltage excitation, and then the limiting support structure 2 is designed in the cavity formed by the groove 5, which can ensure the support of the extreme movement of the MEMS membrane 4. The MEMS membrane 4 is limited by the supporting effect of the limiting support structure 2 and does not break or reduces the risk of breaking.

[0031] It can be seen that the limiting support structure 2 can be a structure integrally formed with the substrate 1. Since the shape of the MEMS membrane 4 can be a rectangular, circular or square structure, the position and number of the limiting support structure 2 can be set accordingly according to the shape of the MEMS membrane 4 after deformation.

[0032] In a specific embodiment of the utility model, four spaced grooves are arranged in the substrate 1, and the mounting structures of each groove and its MEMS membrane are the same, that is, a corresponding MEMS membrane is arranged on each groove through an elastic connector, so that the four MEMS membranes form a capacitor bridge structure.

[0033] Corresponding to the above-mentioned MEMS sensor, the utility model further provides an electronic device, comprising the above-mentioned MEMS sensor. The embodiments of the above-mentioned electronic device can refer to the description in the embodiment of the MEMS sensor, which will not be described one by one here.

[0034] According to the above-mentioned MEMS sensor and electronic device of the utility model, elastic connectors are arranged at both ends of the MEMS membrane, so that the two ends of the MEMS membrane are elastically connected to the substrate respectively, thereby increasing the deformation amount of the MEMS membrane. At the same time, a supporting and limiting structure is arranged in the groove, and the MEMS membrane in the critical deformation state is limited and protected by the supporting and limiting structure, which can ensure that the MEMS membrane is not easy to break under special deformation conditions, and can also expand the deformation degree of the MEMS membrane, thereby increasing the detection range and expanding its application scenarios.

[0035] The MEMS sensor and electronic device according to the present invention are described as examples with reference to the accompanying drawings. However, those skilled in the art should understand that various improvements can be made to the MEMS sensor and electronic device proposed in the present invention without departing from the content of the present invention. Therefore, the protection scope of the present invention should be determined by the content of the attached claims.

Claims

1. A MEMS sensor, comprising a substrate, a groove arranged on the substrate, and a MEMS membrane arranged above the groove, wherein the upper surface of the groove and the MEMS membrane form a parallel plate capacitor structure; characterized in that: An elastic connector is provided at a position where the substrate and the MEMS membrane are connected, and two ends of the MEMS membrane are elastically connected to the substrate through corresponding elastic connectors respectively; The elastic connecting member is used to assist the MEMS membrane in elastic deformation in the groove.

2. The MEMS sensor according to claim 1, characterized in that: The elastic connecting piece is in a wave shape or a sawtooth shape; Furthermore, the extending direction of the elastic connecting member is consistent with the setting direction of the MEMS membrane in a static state.

3. The MEMS sensor according to claim 1, characterized in that: The MEMS membrane is fixed between two elastic connecting members, and the two elastic connecting members are respectively fixedly connected to the substrate, so that the MEMS membrane is fixed on the substrate and covers the groove.

4. The MEMS sensor according to claim 1, characterized in that: The elastic connecting member and the base plate are an integrally formed structure.

5. The MEMS sensor according to claim 1, characterized in that: At least two vertically distributed limiting support structures are arranged in the groove, and the height of the limiting support structure is adapted to the outer shape of the MEMS membrane in a state of maximum deformation.

6. The MEMS sensor according to claim 5, characterized in that: The limiting support structure is a limiting column or a limiting plate with an arc-shaped upper end surface.

7. The MEMS sensor according to claim 5, characterized in that: The position-limiting support structure and the base plate are an integrally formed structure.

8. The MEMS sensor according to claim 1, characterized in that: Four grooves are arranged in the substrate at intervals, and a corresponding MEMS membrane is arranged on each groove through an elastic connecting member, and the four MEMS membranes form a capacitor bridge structure.

9. The MEMS sensor according to claim 1, characterized in that: The MEMS membrane is rectangular, circular or square.

10. An electronic device, characterized in that: Comprising the MEMS sensor according to any one of claims 1 to 9.

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