Pressure sensing module
By introducing a boss structure into the pressure sensing module, the problem of low sensitivity of the piezoresistor is solved, the sensitivity and measurement accuracy of the module are improved, and more accurate pressure measurement is achieved.
Patent Information
- Application Number
- CN202520479141.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-18
- Publication Date
- 2026-01-27
- Estimated Expiration
- 2035-03-18
AI Technical Summary
The pressure sensor modules currently in use have low sensitivity of the pressure-sensitive resistors, which leads to a significant discrepancy between the measured pressure and the actual value.
Introducing a boss structure into the pressure sensing module, the boss structure acts as a stress concentration point, which can more effectively convert external pressure into mechanical stress sensed by the piezoresistor, thereby improving the module's sensitivity. Furthermore, the design of the boss structure reduces nonlinear errors caused by excessive substrate deformation.
The sensitivity and measurement accuracy of the pressure sensing module have been improved, the nonlinear error caused by excessive substrate deformation has been reduced, the varistor is ensured to work under a more stable stress state, and more accurate pressure measurement has been achieved.
Smart Images
Figure CN223841339U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of microelectromechanical technology, and more particularly to a pressure sensing module. Background Technology
[0002] Micro-Electro-Mechanical Systems (MEMS) pressure sensing modules are miniature devices with pressure detection capabilities fabricated using MEMS technology. They are mainly divided into three categories: piezoresistive, capacitive, and resonant, and can be applied in consumer electronics, industrial production, and other fields. Among them, piezoresistive MEMS pressure sensing modules have advantages such as small size, light weight, simple structure, low cost, and high measurement accuracy, and therefore have been widely used.
[0003] The pressure sensor modules in the existing pressure sensing modules have low sensitivity, and the pressure measured differs significantly from the actual value. Utility Model Content
[0004] This utility model provides a pressure sensing module, which further improves the accuracy of the pressure sensing module by setting a boss structure.
[0005] This application provides a pressure sensing module. The pressure sensing module includes: a first substrate and a second substrate, the first substrate including a piezoresistor and a boss structure; the second substrate is located on one side of the first substrate in its thickness direction; a cavity is formed between the first substrate and the second substrate; wherein, the piezoresistor and the boss structure are disposed on the side of the first substrate away from the second substrate; the number of boss structures is multiple, and the multiple boss structures are symmetrically arranged with respect to the center of the first substrate.
[0006] Based on the above solutions, some embodiments of this application provide a pressure sensing module that improves its sensitivity through a boss structure. When external pressure is applied to the module, these boss structures act as stress concentration points, more effectively converting the applied pressure into mechanical stress that the varistor can sense, thereby improving the module's sensitivity. Simultaneously, when the first substrate faces external pressure, the presence of the boss structure reduces the overall degree of bending or deformation, which helps maintain the varistor under a more stable stress state, reducing nonlinear errors caused by excessive substrate deformation and thus improving measurement accuracy.
[0007] In some embodiments, a plurality of the boss structures and a plurality of the varistors are arranged around the center of the first substrate.
[0008] In some embodiments, the number of the boss structures is four, and the four boss structures are arranged diagonally in pairs; the number of the varistors is four, and the four varistors and the four boss structures are alternately arranged along the circumference of the first substrate.
[0009] In some embodiments, the plurality of boss structures have the same shape and the same area.
[0010] In some embodiments, the boss structure includes a first part and a second part, which are connected to form an L-shape.
[0011] In some embodiments, the varistor includes a first varistor and a second varistor, which are disposed adjacent to the boss structure and respectively located at both ends of the boss structure; the first part of the boss structure is disposed opposite to the first varistor at one end away from the second part, and the second part of the boss structure is disposed opposite to the second varistor at one end away from the first part.
[0012] In some embodiments, the edge of the boss structure is equidistant from the distance between two adjacent varistors, and / or the distance between the varistor and the edge of two adjacent boss structures is equidistant.
[0013] In some embodiments, the distance between the edge of the boss structure and the two adjacent varistors is greater than or equal to 20 μm and less than or equal to 50 μm.
[0014] In some embodiments, the dimensions of the first portion of the boss structure in a first direction are equal to the dimensions of the second portion of the boss structure in a second direction; wherein the first direction is perpendicular to the extension direction of the first portion of the boss structure, the second direction is perpendicular to the extension direction of the second portion of the boss structure, and both the extension directions of the first and second portions of the boss structure are perpendicular to the thickness direction of the boss structure.
[0015] In some embodiments, the dimension of the first portion of the boss structure in the first direction is greater than or equal to 50 μm and less than or equal to 125 μm.
[0016] In some embodiments, the pressure sensing module further includes: interconnecting wires electrically connected to the plurality of piezoresistors; the interconnecting wires are disposed around the plurality of piezoresistors and the plurality of boss structures; wherein the spacing between the plurality of boss structures and the interconnecting wires is equal.
[0017] In some embodiments, the spacing between the plurality of boss structures and the interconnecting wires is greater than or equal to 20 μm and less than or equal to 50 μm.
[0018] In some embodiments, the varistor and the boss structure are formed in the same thin film preparation process and etching process; and / or, the thickness of the varistor and the boss structure are equal.
[0019] In some embodiments, the first substrate further includes: a device layer, a first substrate layer, and a buried oxide layer stacked on the side of the first substrate layer away from the second substrate; the first substrate layer, the buried oxide layer, and the device layer are stacked sequentially in a direction away from the second substrate; the varistor and the boss structure are disposed on the side of the buried oxide layer away from the first substrate layer; a groove is provided on the surface of the first substrate layer near the second substrate, and the groove is used to form the cavity. Attached Figure Description
[0020] The accompanying drawings, which are included to provide a further understanding of embodiments of this disclosure and form part of the embodiments of this disclosure, illustrate exemplary embodiments of this disclosure and are used to explain this disclosure, but do not constitute an undue limitation of this disclosure. In the drawings:
[0021] Figure 1 A schematic diagram of a pressure sensing module provided for some embodiments of this disclosure;
[0022] Figure 2 A schematic diagram of the front side of a first substrate provided for some embodiments of this disclosure;
[0023] Figure 3 A schematic diagram of the back side of a first substrate provided for some embodiments of this disclosure;
[0024] Figure 4 A schematic diagram of a pressure sensor provided for some embodiments of this disclosure;
[0025] Figure 5 This is a schematic diagram of an electronic device provided for some embodiments of the present disclosure.
[0026] Figure Labels
[0027] 10. First substrate; 20. Second substrate; 11. Varistor; 12. Boss structure; 121. First part; 122. Second part; 13. Device layer; 14. Buried oxide layer; 15. First substrate layer; 16. First metal layer; 17. First interconnect layer; 18. Metal pad; 19. Interconnect wire; 21. Second substrate layer; 22. Second metal layer; 23. Second interconnect layer; N. Cavity; 100. Pressure sensing module; 150. Integrated circuit; 200. Pressure sensor; 300. Electronic device; 310. Housing. Detailed Implementation
[0028] The technical solutions in some embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application are within the scope of protection of this application.
[0029] Unless the context otherwise requires, throughout the specification and claims, the term "comprising" is interpreted as open-ended and encompassing, meaning "including, but not limited to." In the description, terms such as "one embodiment," "some embodiments," "exemplary embodiment," "example," or "some examples" are intended to indicate that a particular feature, structure, material, or characteristic associated with that embodiment or example is included in at least one embodiment or example of this application. The illustrative representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific feature, structure, material, or characteristic may be included in any suitable manner in any one or more embodiments or examples.
[0030] Micro-Electro-Mechanical Systems (MEMS) pressure sensing modules are miniature devices with pressure detection capabilities fabricated using MEMS technology. They are mainly divided into three categories: piezoresistive, capacitive, and resonant, and can be applied in consumer electronics, industrial production, and other fields. Among them, piezoresistive MEMS pressure sensing modules have advantages such as small size, light weight, simple structure, low cost, and high measurement accuracy, and therefore have been widely used.
[0031] The pressure sensor modules in the existing pressure sensing modules have low sensitivity, and the pressure measured differs significantly from the actual value.
[0032] It should be noted that a piezoresistive MEMS pressure sensing module includes a pressure-sensitive membrane (also called a strain membrane), a piezoresistive resistor, and a circuit structure. The piezoresistive resistor and the circuit structure are electrically connected. The working principle of the piezoresistive MEMS pressure sensing module is as follows: a piezoresistive resistor is fabricated on the strain membrane. Under external pressure, the strain membrane deforms, generating stress. The piezoresistive resistor changes resistance under stress. Finally, the change in resistance is converted into a voltage output through an interconnect structure (such as a Wheatstone bridge). Therefore, the magnitude of the external pressure can be reflected by the voltage output value.
[0033] Based on this, some embodiments of this application provide a pressure sensing module. For example... Figure 1 As shown, the pressure sensing module 100 includes: a first substrate 10 and a second substrate 20.
[0034] The first substrate 10 includes a varistor 11 and a boss structure 12; the second substrate 20 is located on one side of the first substrate 10 in its thickness direction.
[0035] A cavity is formed between the first substrate 10 and the second substrate 20; wherein, the varistor 11 and the boss structure 12 are disposed on the side of the first substrate 10 away from the second substrate 20; there are multiple boss structures 12, and the multiple boss structures 12 are symmetrically arranged with respect to the center of the first substrate 10.
[0036] First, the design of the boss structure 12 creates localized structural changes on the first substrate 10. When external pressure is applied to the module, these boss structures 12 act as stress concentration points, more effectively converting the applied pressure into mechanical stress that the piezoresistor 11 can sense. This means that, compared to a planar substrate without the boss structure 12, the boss structure 12 can convert more external force into changes in resistance, thereby improving the sensitivity of pressure sensing.
[0037] Although the boss structures 12 reduce the directly pressure-bearing planar area, they actually increase the effective area of indirect contact with the varistor 11 through their geometry (typically protrusions or pillars), especially in cases of uneven pressure distribution. This design helps to more effectively capture and transmit pressure changes, allowing even minute pressure changes to be sensed by the varistor 11 and converted into electrical signals.
[0038] Multiple boss structures 12 are arranged symmetrically with respect to the center of the first substrate 10. For example, there are two boss structures 12, which are arranged symmetrically with respect to the center of the first substrate 10.
[0039] This configuration not only enhances the structural stability of the module but also optimizes the stress transmission path from the outside of the module to the varistor 11. This design reduces stress loss, ensuring that pressure changes act more directly and efficiently on the varistor 11, thereby improving sensing efficiency and sensitivity.
[0040] Based on the above solutions, some embodiments of this application provide a pressure sensing module 100, which improves its sensitivity through boss structures 12. When external pressure is applied to the module, these boss structures 12 act as stress concentration points, more effectively converting the applied pressure into mechanical stress that the varistor 11 can sense, thereby improving the module's sensitivity. Simultaneously, when the first substrate faces external pressure, the presence of boss structures reduces the overall degree of bending or deformation, which helps maintain the varistor under a more stable stress state, reducing nonlinear errors caused by excessive substrate deformation and thus improving measurement accuracy.
[0041] like Figure 1 As shown, a plurality of the boss structures 12 and a plurality of the varistors 11 are arranged around the center of the first substrate 10.
[0042] The boss structure 12 and the piezoresistor 11 arranged around the center can capture pressure changes from all directions more evenly. This design reduces measurement errors caused by uneven pressure distribution, allowing the module to more accurately reflect the actual pressure situation.
[0043] Furthermore, the boss structure 12, acting as a stress concentration point, can more effectively convert applied pressure into mechanical stress that the varistor 11 can sense. When multiple boss structures 12 and varistor 11 are arranged around the center, they can form a denser stress-sensing network, thereby improving the module's sensitivity to minute pressure changes. This design also allows the module to better adapt to pressure sources of different sizes and shapes, as pressure can be uniformly transmitted to the varistor 11 through multiple paths.
[0044] like Figure 1 As shown, in some embodiments, the number of boss structures 12 is four, and the four boss structures 12 are arranged diagonally in pairs.
[0045] There are four varistor 11s, and four varistor 11s and four boss structures 12 are alternately arranged along the circumference of the first substrate 10.
[0046] The alternating arrangement of varistor 11 and boss structure 12 allows each varistor 11 to be closer to its corresponding boss structure 12. This means that when the boss structure 12 is subjected to pressure, the stress can be transferred more directly to the adjacent varistor 11, thereby improving the module's sensitivity.
[0047] like Figure 1 As shown, in some embodiments, the multiple boss structures 12 have the same shape and the same area.
[0048] The boss structures 12, with identical shape and area, can distribute stress in the same way and to the same extent when subjected to external pressure. This helps to achieve a more uniform stress distribution, which also means that each varistor 11 receives a similar stress input, thereby improving the accuracy and consistency of measurements.
[0049] like Figure 1 and Figure 2 As shown, in some embodiments, the boss structure 12 includes a first part 121 and a second part 122, which are connected to form an L-shape.
[0050] The varistor 11 includes a first varistor 11 and a second varistor 11, which are arranged adjacent to the boss structure 12 and located at both ends of the boss structure 12.
[0051] The first part 121 of the boss structure 12 is disposed opposite to the first varistor 11 at one end away from the second part 122, and the second part 122 of the boss structure 12 is disposed opposite to the second varistor 11 at one end away from the first part 121.
[0052] In other words, the L-shaped boss structure 12 is formed by the interconnection of the first part 121 and the second part 122.
[0053] In some embodiments, such as Figure 1 and Figure 2 As shown, the distance between the end of the first part 121 of the boss structure 12 away from the second part 122 and the first varistor 11 is equal to the distance between the end of the second part 122 of the boss structure 12 away from the first part 121 and the second varistor 11. That is, the distance between the edge of the boss structure 12 and the two adjacent varistors 11 is equal.
[0054] In some embodiments, the distance between the edge of the boss structure 12 and the distance between the two adjacent varistors 11 is equal, and / or the distance between the varistor 11 and the distance between the edge of the two adjacent boss structures 12 is equal.
[0055] For example, only the edge of the boss structure 12 is equidistant from the two adjacent varistors 11, or the varistor 11 is equidistant from the edges of the two adjacent boss structures 12; or the edge of the boss structure 12 is equidistant from the two adjacent varistors 11, and the varistor 11 is equidistant from the edges of the two adjacent boss structures 12.
[0056] In some embodiments, the distance L1 between the end of the first portion 121 of the boss structure 12 away from the second portion 122 and the first varistor 11 is greater than or equal to 20 μm and less than or equal to 50 μm.
[0057] In other words, the distance L1 between the edge of the boss structure 12 and the two adjacent varistors 11 is greater than or equal to 20μm and less than or equal to 50μm.
[0058] Reference Figure 2 In some embodiments, the first portion 121 of the boss structure 12 has the same dimension in the first direction X as the second portion 122 of the boss structure in the second direction Y.
[0059] Wherein, the first direction X is perpendicular to the extension direction of the first part 121 of the boss structure 12, the second direction Y is perpendicular to the extension direction of the second part 122 of the boss structure 12, and the extension directions of the first part 121 and the second part 122 of the boss structure 12 are both perpendicular to the thickness direction Z of the boss structure 12.
[0060] The first part 121 of the boss structure 12 has a dimension in the first direction X that is equivalent to the width of the first part 121 of the boss structure 12, and the second part 122 of the boss structure has a dimension in the second direction Y that is equivalent to the width of the second part 122 of the boss structure 12.
[0061] In some embodiments, the width L2 of the first portion 121 of the boss structure 12 is greater than or equal to 50 μm and less than or equal to 125 μm.
[0062] The larger the area of the L-shaped boss structure 12, the lower the sensitivity will be. The distance between the end of the first part 121 of the boss structure 12 away from the second part 122 and the first varistor 11 is greater than or equal to 20μm to prevent crosstalk between the boss structure 12 and other structures; the width of the first part 121 of the boss structure 12 is less than or equal to 125μm to avoid the width of the boss structure 12 exceeding the length of the varistor 11, thereby affecting the stress distribution in the region of the varistor 11.
[0063] like Figure 1 and Figure 2 As shown, in some embodiments, the pressure sensing module 100 further includes: interconnecting wires 19 electrically connected to a plurality of piezoresistors 11; the interconnecting wires 19 are arranged around the plurality of piezoresistors 11 and a plurality of boss structures 12; wherein the spacing between the plurality of boss structures 12 and the interconnecting wires 19 is equal.
[0064] In some embodiments, the distance L3 between the plurality of boss structures 12 and the edge of the cavity is greater than or equal to 20 μm and less than or equal to 50 μm.
[0065] In some embodiments, the varistor 11 and the boss structure 12 are made of the same material; and / or, the varistor 11 and the boss structure 12 have the same thickness.
[0066] The fact that the varistor 11 and the boss structure 12 are made of the same material means that the varistor 11 and the boss structure 12 are formed in the same thin film preparation process and etching process.
[0067] In some embodiments, the first substrate 10 further includes: a first substrate layer 15, and a buried oxide layer 14 stacked on the side of the first substrate layer 15 away from the second substrate 20; a varistor 11 and a boss structure 12 are disposed on the side of the buried oxide layer 14 away from the first substrate layer 15; a groove is provided on the surface of the first substrate layer 15 near the second substrate 20, and the groove is used to form a cavity.
[0068] like Figure 1 As shown, the first substrate 10 further includes a device layer 13, a first metal layer 16, and a first interconnect layer 17. The device layer 13 is etched to form a varistor 11 and a boss structure 12.
[0069] The first metal layer 16 is annular, and the first metal layer 16 is connected to the non-cavity N portion of the first substrate layer 15 near the side away from the buried oxide layer 14; the first connecting layer 17 is connected to the first metal layer 16 near the first metal layer 16, and connected to the second substrate 20 on the side away from the first metal layer 16.
[0070] The width of the first metal layer 16 is greater than 600 μm, and the distance between the side of the first metal layer 16 away from the cavity N and the boundary of the first substrate 10 is greater than or equal to 50 μm; the distance between the side of the first metal layer 16 close to the cavity N and the boundary of the cavity N is greater than 50 μm. The thickness of the first interconnect layer 17 is 10-60 μm.
[0071] The second substrate 20 includes: a second substrate layer 21, a second metal layer 22, and a second interconnect layer 23.
[0072] The second metal layer 22 is annular, and the side of the second metal layer 22 away from the first substrate 10 is connected to the second substrate layer 21; the side of the second connecting layer 23 away from the first substrate 10 is connected to the second metal layer 22, and the side closer to the first substrate 10 is connected to the first substrate 10.
[0073] The width of the second metal layer 22 is greater than 600 μm, and the distance between the side of the second metal layer 22 away from the cavity N and the boundary of the second substrate 20 is greater than 50 μm; the distance between the side of the second metal layer 22 near the cavity N and the boundary of the cavity N is greater than 50 μm. The thickness of the second connecting layer 23 is 10-60 μm.
[0074] For example, the material of the first metal layer 16 or the second metal layer 22 may be a Cr / Au layer, a Ti / Cr / Au layer, a Cr / Ni / Au layer, etc.
[0075] The first substrate 10 includes four varistors 11 and four metal pads 18. The four varistors 11 are connected in series and end to end to form a loop circuit.
[0076] Among them, the four varistors 11 are located at the center of the four edges of the varistor film (refer to...). Figure 2 The four resistive films have a consistent edge distance, which is a value between 0 and 20 μm. The width of the four varistor 11 is the same as the total length, and the number of folds can be 1 to 10. The top and bottom varistor 11 have the same structural dimensions, and the left and right varistor 11 have the same structural dimensions. In this application, there are two folds.
[0077] For example, the material of the interconnecting wire 19 can be a low resistivity material, such as any one or more combinations of Al, Ti / Al, Au and Cr / Au, so that a good circuit path can be formed.
[0078] In this way, the varistor 11 is located on the first substrate 10, the interconnecting wire 19 is located on the first substrate 10, the varistor 11 and the interconnecting wire 19 are electrically connected, and multiple metal pads 18 are connected to the middle section of the interconnecting wire 19, that is, the four corners of the first substrate 10, thereby forming a Wheatstone bridge structure.
[0079] The Wheatstone bridge structure includes: one input terminal, two output terminals, and one ground terminal.
[0080] It should be noted that the two output terminals of the Wheatstone bridge structure are located diagonally, while the positions of the input terminal and the ground terminal are not required.
[0081] The metal pad 18 can be square, rectangular, circular, elliptical, or other structures, and the side length or straight dimension L1” of the pad is 50-150μm.
[0082] In some embodiments, the first substrate layer 15 is an SOI substrate layer. A portion of the SOI substrate layer may be etched to form a cavity, within which a pressure-sensitive film may be formed. (Refer to...) Figure 1 and Figure 3 The cavity is a square cavity N, and the side length of cavity N can be 500-2000μm.
[0083] For example, the first substrate layer 15 can be made of silicon. The buried oxide layer 14 can be made of an insulating material, such as any one or more combinations of SiO2, SiN, and glass. In this case, the first substrate layer 15 and the buried oxide layer 14 can constitute a pressure-sensitive film.
[0084] In other words, the region where the varistor 11 is located is directly opposite to the region where the varistor film is located, corresponding to the orthogonal projection of the multiple varistor 11 onto the first substrate layer 15, and is located within the region where the varistor film is located. The first metal layer 16 and the first connecting layer 17 surround it from above, and the second metal layer 22 and the second connecting layer 23 surround it from below. The second metal layer 22 and the second connecting layer 23 are then fixed to the second substrate layer 21, thereby forming a sealed or vacuum structure.
[0085] For example, the material of the first connecting layer 17 or the second connecting layer 23 may be a eutectic solder, such as one or more combinations of AuSn, AgSn, CuSn and SnAgCu.
[0086] In some embodiments, the first substrate 10 and the second substrate 20 are enclosed to form a vacuum cavity N.
[0087] In some embodiments, when the first substrate 10 and the second substrate 20 enclose a vacuum cavity N, the pressure sensing module 100 further includes a suction plate located within the vacuum cavity N.
[0088] The aforementioned pressure sensing module 100 is an absolute pressure sensing module 100, which can measure the absolute value of pressure changes and has the advantages of high accuracy and a large measurement range; however, for some measurements related to water pressure and air pressure, the absolute pressure sensing module 100 is not suitable. Therefore, a gauge pressure sensing module 100 is proposed as follows:
[0089] In some embodiments, the second substrate layer 21 has through holes; the through holes allow the back side of the diaphragm to be connected to the outside atmosphere, so as to realize the gauge pressure / differential pressure measurement of the pressure sensing module 100.
[0090] Here, there are no restrictions on the size of the through hole. In some examples, the diameter of the through hole 50 ranges from 0 to 100 μm, for example, 0 μm, 10 μm, 30 μm, 50 μm, 70 μm, or 100 μm.
[0091] For example, an insulating layer can be provided on the sidewall of the through hole. Figure 1 (not shown in the image), thus improving the safety and reliability of the pressure sensing module 100.
[0092] Understandably, the pressure gauge cavity N is the aforementioned cavity N. Using the through hole 50, the pressure gauge cavity N can be connected to the external atmospheric environment, so that the pressure of the pressure gauge cavity N is equal to the external pressure. Moreover, when the pressure gauge cavity N is formed by the first substrate 10 and the second substrate 20, the pressure sensing module 100 is a pressure gauge type pressure sensing module 100, which can be measured with atmospheric pressure as a reference. It has the advantage of being easy to manufacture and can be used to measure the relative pressure change value of media such as water pressure and air pressure.
[0093] This application also provides a method for preparing a pressure sensing module, used to prepare the aforementioned pressure sensing module.
[0094] Preparation methods include:
[0095] S1. A buried oxide layer 14 and an initial device layer are sequentially formed on the first substrate layer 15.
[0096] S2. A varistor 11 and a boss structure 12 are etched on the initial device layer, and the etched portion exposes the buried oxide layer 14 on the side away from the first substrate layer 15.
[0097] like Figure 3 and Figure 4As shown, some embodiments of this disclosure also provide a pressure sensor 200. The pressure sensor 200 includes a pressure sensing module 100 and an integrated circuit 150 provided in the above-described technical solutions.
[0098] The integrated circuit 150 is electrically connected to the metal pad 18 of the pressure sensing module 100.
[0099] Understandably, the pressure-sensitive resistor 11 generates a voltage signal when it receives pressure, and transmits this voltage signal to the integrated circuit 150. The integrated circuit 150 can further process the voltage signal and output it as a digital signal to provide feedback on the pressure magnitude. In this way, pressure measurement data can be transmitted.
[0100] like Figure 5 As shown, some embodiments of this disclosure also provide an electronic device 300. The electronic device 300 includes a housing 310 and a pressure sensor 200 disposed on the housing 310.
[0101] In some examples, the electronic device 300 can be a mobile phone or a computer; it can also be a portable electronic device 300, so that the pressure sensing module 100 can be applied to technical scenarios that require pressure measurement, such as automobiles and industrial manufacturing.
[0102] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.
Claims
1. A pressure sensing module, characterized in that, include: The first substrate includes a varistor and a boss structure; The second substrate is located on one side of the first substrate in its own thickness direction; a cavity is formed between the first substrate and the second substrate; The varistor and the boss structure are disposed on the side of the first substrate away from the second substrate; there are multiple boss structures, and the multiple boss structures are symmetrically arranged with respect to the center of the first substrate.
2. The pressure sensing module according to claim 1, characterized in that, The plurality of said boss structures and the plurality of said varistors are arranged around the center of the first substrate.
3. The pressure sensing module according to claim 1, characterized in that, The number of the boss structures is four, and the four boss structures are arranged diagonally in pairs. The number of varistors is four, and the four varistors and the four boss structures are alternately arranged along the circumference of the first substrate.
4. The pressure sensing module according to claim 1, characterized in that, The multiple boss structures have the same shape and the same area.
5. The pressure sensing module according to claim 1, characterized in that, The boss structure includes a first part and a second part, which are connected to form an L-shape.
6. The pressure sensing module according to claim 5, characterized in that, The varistor includes a first varistor and a second varistor, which are arranged adjacent to the boss structure and respectively located at both ends of the boss structure; The first part of the boss structure is disposed opposite to the first varistor at one end away from the second part, and the second part of the boss structure is disposed opposite to the second varistor at one end away from the first part.
7. The pressure sensing module according to claim 6, characterized in that, The distance between the edge of the boss structure and the distance between the two adjacent varistors is equal, and / or the distance between the varistor and the edges of the two adjacent boss structures is equal.
8. The pressure sensing module according to claim 7, characterized in that, The distance between the edge of the boss structure and the two adjacent varistors is greater than or equal to 20 μm and less than or equal to 50 μm.
9. The pressure sensing module according to claim 5, characterized in that, The dimension of the first part of the boss structure in the first direction is equal to the dimension of the second part of the boss structure in the second direction; Wherein, the first direction is perpendicular to the extension direction of the first part of the boss structure, the second direction is perpendicular to the extension direction of the second part of the boss structure, and both the extension directions of the first part and the second part of the boss structure are perpendicular to the thickness direction of the boss structure.
10. The pressure sensing module according to claim 9, characterized in that, The dimension of the first part of the boss structure in the first direction is greater than or equal to 50 μm and less than or equal to 125 μm.
11. The pressure sensing module according to claim 1, characterized in that, The pressure sensing module also includes: Interconnecting wires are electrically connected to the plurality of varistors; the interconnecting wires are arranged around the plurality of varistors and the plurality of boss structures. The spacing between the plurality of the boss structures and the interconnecting wires is equal.
12. The pressure sensing module according to claim 11, characterized in that, The spacing between the plurality of boss structures and the interconnecting wires is greater than or equal to 20 μm and less than or equal to 50 μm.
13. The pressure sensing module according to any one of claims 1 to 12, characterized in that, The varistor and the boss structure are formed in the same thin film preparation process and etching process; and / or... The thickness of the varistor and the boss structure are equal.
14. The pressure sensing module according to any one of claims 1 to 12, characterized in that, The first substrate further includes: a device layer, a first substrate layer, and a buried oxide layer stacked on the side of the first substrate layer away from the second substrate; the first substrate layer, the buried oxide layer, and the device layer are stacked sequentially in a direction away from the second substrate; The varistor and the boss structure are located on the side of the buried oxide layer away from the first substrate layer; The first substrate layer has a groove on its surface near the second substrate, and the groove is used to form the cavity.