MEMS sensor and electronic atomization device

Abstract

The application discloses a MEMS sensor and an electronic atomization device, the MEMS sensor comprising a substrate, a substrate, a first electrode plate, a second electrode plate and a conductive contact; the first surface of the substrate has a groove, and the second surface of the substrate has a Wheatstone bridge circuit, the bridge arm of the Wheatstone bridge circuit comprising a piezoresistor; the substrate covers the groove to form a sealed cavity; the first electrode plate is arranged on the bottom wall of the groove; the second electrode plate is arranged on the substrate and is arranged in a spaced manner with the first electrode plate; the conductive contact is arranged on the substrate and / or the substrate and is electrically connected with at least one of the first electrode plate and the second electrode plate; wherein the first electrode plate and the second electrode plate are configured to repel each other or attract each other under the condition of being electrified. In this way, the deflection of the strain film is always small, thereby, the problem that the deformation of the substrate does not change linearly with the pressure is well improved, so that the detection accuracy of the MEMS sensor is improved.

Description

Technical Field

[0001] This application relates to the field of sensor technology, specifically to a MEMS sensor and an electronic atomization device. Background Technology

[0002] In recent years, with the rapid development of MEMS (Micro-Electro-Mechanical System) technology, it has been widely applied in the sensor field. Traditional MEMS piezoresistive pressure sensors are based on the piezoresistive effect of single-crystal silicon. They typically use a Wheatstone bridge structure to convert external pressure signals into corresponding electrical signals, and the magnitude of the external pressure signal can be determined by measuring the value of this electrical signal. However, this type of MEMS piezoresistive pressure sensor suffers from inaccurate detection. Summary of the Invention

[0003] This application provides a MEMS sensor and an electronic atomization device to solve the problem of inaccurate detection by MEMS sensors.

[0004] According to a first aspect of this application, some embodiments of this application provide a MEMS sensor, including a substrate, a base plate, a first electrode plate, a second electrode plate, and conductive contacts; the substrate has opposing first and second surfaces; the first surface has a groove, and the second surface has a Wheatstone bridge circuit, the arms of the Wheatstone bridge circuit including varistors; the base plate covers the groove to form a sealed cavity; the first electrode plate is disposed on the bottom wall of the groove; the second electrode plate is disposed on the base plate and spaced apart from the first electrode plate; the conductive contacts are disposed on the substrate and / or the base plate and are electrically connected to at least one of the first and second electrode plates; wherein the first and second electrode plates are configured to repel or attract each other when energized.

[0005] In some embodiments, the first plate and the second plate form a parallel plate capacitor, and the conductive contacts include a first conductive contact electrically connected to the first plate and a second conductive contact electrically connected to the second plate.

[0006] In some embodiments, the first electrode plate is disposed on the bottom surface of the groove; the second electrode plate is disposed on the surface of the substrate exposed to the sealing cavity; the first electrode plate and the second electrode plate are disposed opposite to each other.

[0007] In some embodiments, one of the first and second electrode plates comprises a permanent magnet material, and the other is an electromagnet; the conductive contact is electrically connected to the electromagnet to change the polarity of the electromagnet.

[0008] In some embodiments, both the first electrode plate and the second electrode plate are electromagnets; the conductive contacts are electrically connected to the first electrode plate and the second electrode plate respectively, for changing the polarity of the electromagnet.

[0009] In some embodiments, the substrate has a first conductive hole and a second conductive hole; the first conductive contact is disposed on the surface of the substrate opposite to the substrate and is electrically connected to the first electrode plate through the first conductive hole, and the second conductive contact is disposed on the surface of the substrate opposite to the substrate and is electrically connected to the second electrode plate through the second conductive hole.

[0010] In some embodiments, the Wheatstone bridge circuit includes four sets of varistors and four sets of conductive regions. The varistors generate resistance changes in response to pressure changes applied to the substrate, thereby converting the pressure signal into an electrical signal. The conductive regions are used to lead out the electrical signal.

[0011] In some embodiments, the substrate is a semiconductor substrate; each group of varistors includes two parallel and spaced sub-varistors, and a heavily doped contact region formed between the sub-varistors, the heavily doped contact region being used to electrically connect the two parallel and spaced sub-varistors.

[0012] In some embodiments, the varistor and the heavily doped contact region are formed on the substrate, which is also covered with a dielectric layer, and four sets of the conductive regions are formed on the dielectric layer.

[0013] In some embodiments, the side of the dielectric layer away from the substrate is also covered with a passivation layer, and the four sets of conductive regions are at least partially exposed to the passivation layer.

[0014] According to a second aspect of this application, some embodiments of this application provide an electronic atomization device, including a liquid storage unit, an atomization component, a MEMS sensor, a power supply, and a control circuit; the liquid storage unit is used to store an aerosol generation matrix, and the liquid storage unit has an aerosol inlet end and an outlet end; the atomization component is disposed on the airflow path from the inlet end to the outlet end, and is used to atomize the aerosol generation matrix; the MEMS sensor is the MEMS sensor provided in any of the above embodiments; the MEMS sensor is disposed on the airflow channel of the electronic atomization device, and is used to detect air pressure changes in the airflow channel; the power supply is used to provide voltage to the atomization component and the MEMS sensor; the control circuit is electrically connected to the power supply, the atomization component, and the MEMS sensor respectively; the control circuit is used to apply an electrical signal to a first electrode plate and a second electrode plate according to the amount of change in the output voltage of the MEMS sensor caused by the air pressure change in the airflow channel, so that the first electrode plate and the second electrode plate attract or repel each other, so that the amount of change in the output voltage of the MEMS sensor is less than or equal to a preset threshold.

[0015] In some embodiments, the preset threshold is zero; the control circuit is also used to detect whether the change in the output voltage of the MEMS sensor is zero; and when the change in the output voltage of the MEMS sensor is detected to be zero, to determine the magnitude of the air pressure based on the electrical signals applied to the first electrode plate and the second electrode plate.

[0016] According to the MEMS sensor of the above embodiment, a first electrode plate is disposed on the bottom wall of a groove, and a second electrode plate is disposed on a substrate, spaced apart from the first electrode plate. The first and second electrode plates are configured to repel or attract each other when energized. When the substrate of the sensor is subjected to pressure in the direction close to the substrate, the first and second electrode plates can be energized to make the charge on the first electrode plate the same as the charge on the second electrode plate, thereby displacing the first electrode plate away from the substrate and thus counteracting the displacement of the substrate in the direction close to the substrate caused by changes such as airflow. When the substrate of the sensor is subjected to pressure away from the substrate, the first and second electrode plates can be energized to make the charge on the first electrode plate opposite to the charge on the second electrode plate, thereby displacing the first electrode plate in the direction close to the substrate and thus counteracting the displacement of the substrate away from the substrate caused by changes such as airflow. Therefore, during the use of the MEMS sensor, the deflection of the strain membrane is always small, thereby effectively improving the problem that the deformation of the substrate does not change ideally linearly with the pressure, thus improving the detection accuracy of the MEMS sensor of this application embodiment. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 Top view of a MEMS sensor provided for some embodiments of this application;

[0019] Figure 2 for Figure 1 A schematic cross-sectional view along line II-II;

[0020] Figure 3 This is a schematic diagram of the structure of a MEMS sensor provided in some embodiments of this application;

[0021] Figure 4 This is a schematic diagram of the structure of a MEMS sensor provided in some other embodiments of this application;

[0022] Figure 5 This application provides schematic diagrams of the structure of MEMS sensors in some of its embodiments.

[0023] Figure 6 A flowchart illustrating a method for fabricating a MEMS sensor provided in some embodiments of this application;

[0024] Figure 7 for Figure 6 Flowchart of S10 in the middle;

[0025] Figure 8 for Figure 6 Flowchart of S30 in China;

[0026] Figure 9 for Figure 6 Flowchart of S40 in China;

[0027] Figure 10 Flowcharts illustrating MEMS sensor fabrication methods provided in other embodiments of this application;

[0028] Figure 11 This is a schematic diagram of the structure of an electronic atomizing device provided in some embodiments of this application;

[0029] Figure 12 for Figure 11 Functional module diagram of an electronic atomizing device.

[0030] Explanation of icon numbers:

[0031] 10-Substrate, 11-First surface, 12-Second surface, 13-Groove, 14-Wheatstone bridge circuit, 140-Varistor, 141-Sub-Varistor, 142-Conductive region, 143-Heavily doped contact region, 144-Conductive lead, 15-Dielectric layer, 16-Passivation layer; 20-Substrate, 21-First conductive hole, 22-Second conductive hole, 23-Third conductive hole; 30-First electrode plate, 31-First lead, 32-Second lead; 40-Conductive contact, 41-First conductive contact; 42-Second conductive contact; 70-Second electrode plate; 80-First sealing ring; 90-Second sealing ring; 100-MEMS sensor; 200-Liquid storage assembly; 300-Atomization assembly; 400-Control circuit; 1000A-Liquid storage unit, 1000B-Control unit, 1000-Electronic atomization device Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing description of the drawings, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such processes, methods, products, or apparatus.

[0034] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0035] In the description of the embodiments of this application, the technical terms "first," "second," "third," etc., are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more (including two), such as two, three, etc., unless otherwise explicitly defined. Similarly, "multiple sets" refers to two or more sets (including two sets), and "multiple pieces" refers to two or more pieces (including two pieces).

[0036] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0037] In the description of the embodiments of this application, the technical terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the relative orientation or positional relationship between the components in a certain posture (as shown in the accompanying drawings) as shown in the drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0038] In the description of the embodiments of this application, unless otherwise expressly specified and limited, the technical terms such as "installation," "connection," "joining," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in the embodiments of this application can be understood according to the specific circumstances.

[0039] In recent years, with the rapid development of MEMS technology, it has been widely applied in the sensor field. Traditional MEMS sensors are based on the piezoresistive effect of single-crystal silicon, and typically use a Wheatstone bridge structure to convert external pressure signals into corresponding electrical signals. The magnitude of the external pressure signal is obtained by measuring the value of this electrical signal.

[0040] However, the inventors of this application discovered through research that as the external pressure increases, the displacement (or "deformation") of the strain membrane in the sensor structure will not always exhibit an ideal linear change. This causes the resistance value of the bridge arm of the Wheatstone bridge to not always exhibit a linear change. In other words, the deflection of the strain membrane increases and the linearity deteriorates, which in turn leads to poor linearity of the test results. This type of MEMS sensor has the problem of inaccurate detection.

[0041] The inventors of this application compensate for the deflection of the strain membrane by setting a first electrode plate 30 and a second electrode plate 70, which effectively improves the problem that the deformation of the substrate does not change in an ideal linear manner with the pressure, thereby improving the detection accuracy of the MEMS sensor in the embodiment of this application.

[0042] The present application will now be described in detail with reference to the accompanying drawings and embodiments.

[0043] Please refer to Figure 1 and Figure 2 , Figure 1 Top view of a MEMS sensor provided for some embodiments of this application; Figure 2 for Figure 1 A schematic cross-sectional view along line II-II.

[0044] The MEMS sensor 100 provided in this application embodiment includes a substrate 10, a base plate 20, a first electrode plate 30, a second electrode plate 70, and conductive contacts 40.

[0045] In one embodiment, the substrate 10 can be made of silicon-based materials, such as a single-crystal silicon wafer. Single-crystal silicon wafers are a common substrate for semiconductor devices, on which metal layers can be deposited and metal ions can be doped to construct semiconductor devices. In another embodiment, the MEMS sensor 100 needs to have a rollable characteristic. In this case, polyacetamide / polyimide (PI), i.e., a PI thin film, can be used as the substrate 10, and a single-crystal silicon layer is deposited on it to fabricate the rollable MEMS sensor 100. This application uses a semiconductor substrate 10 as an example for illustration.

[0046] In some embodiments, the substrate 10 has a first surface 11 and a second surface 12 opposite to each other, and the distance between the first surface 11 and the second surface 12 is the thickness of the substrate 10. The first surface 11 has a groove 13, the cross-sectional shape of which is not limited along the thickness direction of the substrate 10, and can be, for example, square, rectangular, or trapezoidal, etc., and this application does not impose any specific limitations on it. The second surface 12 has a Wheatstone bridge circuit 14, the bridge arms of which include varistors 140.

[0047] In some embodiments, see Figure 1The Wheatstone bridge circuit 14 includes four sets of varistors 140. Each varistor 140 responds to a change in resistance in response to a pressure change applied to the substrate 10, thereby converting the pressure signal into an electrical signal. Each set of varistors 140 includes two parallel and spaced-apart sub-varistors 141. In one embodiment, the four sets of varistors 140 are arranged in the same direction, for example... Figure 1 In the X-direction, four sets of varistors 140 are located in the central region of the substrate 10, forming... Figure 1 The rhombus shape shown is distributed at the four corners of the rhombus. In another embodiment, the four groups of varistors 140 are arranged in different directions; for example, two groups of varistors 140 are arranged according to... Figure 1 The four sets of varistors 140 are arranged in the X direction; the other two sets are arranged along the Y direction. Alternatively, in another embodiment, the four sets of varistors 140 are arranged in a rectangle (not shown), and the arrangement direction of the four sets of varistors 140 is the same.

[0048] In some embodiments, the Wheatstone bridge circuit 14 further includes four sets of conductive regions 142 for leading out electrical signals. In one embodiment, such as... Figure 1 As shown, four sets of varistors 140 are respectively arranged in the middle of the substrate 10, and four conductive regions 142 are respectively arranged around the four sets of varistors 140. Specifically, the four conductive regions 142 are respectively arranged at the four corners of the substrate 10. In another embodiment, the four sets of varistors 140 are respectively arranged at the four corners of the substrate 10 (not shown), and the four conductive regions 142 are arranged in the middle of the substrate 10.

[0049] Furthermore, in some embodiments, the Wheatstone bridge circuit 14 further includes heavily doped contact regions 143 formed between the sub-varistors 141. The heavily doped contact regions 143 are used to electrically connect two parallel and spaced sub-varistors 141 in the group of varistors 140. The heavily doped contact regions 143 are regions that have conductive properties after being doped with metal ions. Please refer to [link to relevant documentation]. Figure 2 and Figure 3In some embodiments, a varistor 140 and a heavily doped contact region 143 are formed on a substrate 10. A dielectric layer 15 is also formed on the substrate 10, and four sets of conductive regions 142 are formed on the dielectric layer 15. The dielectric layer 15 can serve as a protective layer and an insulating layer, and the material of the dielectric layer 15 can be silicon dioxide or silicon nitride, etc. The dielectric layer 15 may have through-holes, through which the conductive regions 142 and their conductive leads 144 can be electrically connected to the varistor 140. Optionally, the material of the conductive leads 144 is at least one of copper, nickel-chromium alloy, iron, or platinum. Optionally, in some embodiments, a passivation layer 16 is also formed on the side of the dielectric layer 15 away from the substrate 10, and the four sets of conductive regions 142 are at least partially exposed in the passivation layer 16. The passivation layer 16 has a dense surface that can be used to resist moisture erosion and device oxidation. The passivation layer 16 has a hollow area corresponding to the conductive area 142, so that the conductive area 142 is exposed to the external environment to facilitate the output of electrical signals.

[0050] In some embodiments, the substrate 20 can be a glass substrate or a ceramic substrate, etc. The substrate 20 can cover the groove 13 and form a sealed cavity with the substrate 10, that is... Figure 2 The indicated groove 13 is a sealed cavity. In one embodiment, the substrate 20 can be bonded to the substrate 10 to form a sealed cavity. Exemplarily, in some embodiments, the substrate 20 and the substrate 10 can be bonded together using metallic chromium under preset temperature and / or preset pressure conditions. The specific preset temperature and pressure need to be determined based on the bonding material and the actual equipment used, and will not be specifically described here. Those skilled in the art can understand the concept of this embodiment based on the above description. In other embodiments, the substrate 20 can be directly bonded to the substrate 10.

[0051] In some embodiments, a first electrode plate 30 is disposed on the bottom wall of the groove 13, and the first electrode plate 30 is conductive and spaced apart from the substrate 20. A second electrode plate 70 is disposed on the substrate 20 and spaced apart from the first electrode plate 30. ， The first electrode 30 and the second electrode 70 are configured to repel or attract each other when an electric current is applied. The basis for this configuration could be the principle of like charges repelling and unlike charges attracting, such as... Figure 2 As shown; or the principle of magnetic attraction and repulsion between like poles, such as... Figure 3 As shown.

[0052] Please see Figure 2In some embodiments, the first electrode 30 and the second electrode 70 form a parallel electrode capacitor. The first electrode 30 is disposed on the bottom surface of the groove 13, which is the surface of the groove 13 near the substrate 20. The second electrode 70 is disposed on the surface of the substrate 20 exposed to the sealed cavity, which is the surface of the substrate 20 near the substrate 10. The first electrode 30 and the second electrode 70 are disposed opposite to each other. When opposite charges are applied to the first electrode 30 and the second electrode 70, according to the principle of attraction between opposite charges, they move closer to each other. In some embodiments of this application, the first electrode 30 moves closer to the substrate 20 after being energized. Figure 2 In this context, the direction closer to the substrate 20 can refer to the vertically downward direction, which is the opposite direction of the Z direction, and is defined as the first direction. When the first electrode 30 and the second electrode 70 are supplied with charges of the same polarity, according to the principle of like charges repelling each other, they undergo a relative displacement. In some embodiments of this application, the first electrode 30 undergoes a displacement away from the substrate 20 after being energized. Figure 2 In this context, the direction away from the substrate 20 can refer to the vertically upward direction, i.e., the Z direction, which is defined as the second direction. This will be used as an example in subsequent embodiments.

[0053] In some embodiments, the first electrode 30 can be made of materials such as platinum, nickel, tungsten, etc., which are suitable as thermocouples and capacitor electrodes. Platinum is a good thermistor, and its resistance value changes linearly with temperature. The second electrode 70 can also be made of materials such as gold, platinum, nickel, copper, tin oxide, manganese oxide, etc., which are suitable as capacitor electrodes.

[0054] Further, in some embodiments, the conductive contact 40 includes a first conductive contact 41 electrically connected to the first electrode plate 30 and a second conductive contact 42 electrically connected to the second electrode plate 70. The first conductive contact 41 and the second conductive contact 42 can be simultaneously disposed on the substrate 10, simultaneously disposed on the substrate 20, or partially disposed on the substrate 10 with the remainder disposed on the substrate 20. This application does not impose specific limitations on this; this application uses the example of the first conductive contact 41 and the second conductive contact 42 being disposed on the substrate 20 for description. In some embodiments of this application, the material of the first conductive contact 41 is the same as the material of the first electrode plate 30, and the material of the second conductive contact 42 is the same as the material of the second electrode plate 70. This can reduce contact resistance, reduce heat generation, and improve energy utilization. Optionally, in other embodiments, the material of the first conductive contact 41 may be different from the material of the first electrode plate 30, and / or the material of the second conductive contact 42 may be different from the material of the second electrode plate 70.

[0055] Furthermore, in some embodiments, the substrate 20 has a first conductive hole 21 and a second conductive hole 22, a first conductive contact 41 is disposed on the surface of the substrate 20 away from the substrate 10 and is electrically connected to the first electrode plate 30 through the first conductive hole 21 and the first lead 31, and a second conductive contact 42 is disposed on the surface of the substrate 20 away from the substrate 10 and is electrically connected to the second electrode plate 70 through the second conductive hole 22.

[0056] Specifically, in some embodiments, there is one first conductive hole 21 and one second conductive hole 22. One end of the first electrode plate 30 is connected to a first lead 31. The first conductive hole 21 is used to lead out the first lead 31. The same material as the first lead 31 is deposited in the first conductive hole 21 to form a first conductive contact 41. The same material as the second electrode plate 70 can be deposited in the second conductive hole 22 to form a second conductive contact 42. This embodiment can realize the electrical connection between the first conductive contact 41 and the first electrode plate 30, and the electrical connection between the second conductive contact 42 and the second electrode plate 70. Current can be passed to the first electrode plate 30 through the first conductive contact 41, and to the second electrode plate 70 through the second conductive contact 42. The structure is simple and the preparation method is quick.

[0057] Optionally, in other embodiments, the first conductive hole 21 and the second conductive hole 22 may also be disposed on the substrate 10, or one may be disposed on the substrate 10 and the other on the substrate 20. This application does not impose specific limitations and can select according to needs. The embodiments of this application are described using the example of the first conductive hole 21 and the second conductive hole 22 being disposed on the substrate 20.

[0058] Please see also Figure 3 and Figure 4 In other embodiments, one of the first electrode plate 30 and the second electrode plate 70 includes a permanent magnet material, and the other is an electromagnet; the conductive contact 40 is electrically connected to the electromagnet to change the polarity of the electromagnet. Specifically, the polarity of the permanent magnet material is fixed. In this embodiment, the polarity of the permanent magnet material near the electromagnet is described as N pole. The magnetism of the electromagnet near the permanent magnet material can be determined by Ampere's rule. Therefore, the polarity of the electromagnet can be changed by changing the direction of the current in the electromagnet. When the magnetism of the electromagnet near the permanent magnet material is N pole, the first electrode plate 30 and the second electrode plate 70 repel each other. When the magnetism of the electromagnet near the permanent magnet material is S pole, the first electrode plate 30 and the second electrode plate 70 attract each other.

[0059] Please see Figure 3In one embodiment, the first electrode 30 is a permanent magnet material, the second electrode 70 is an electromagnet, and the conductive contact 40 includes two spaced-apart second conductive contacts 42, which are electrically connected to the second electrode 70 and used to apply a DC voltage to the second electrode 70 to change its polarity. Correspondingly, the substrate 20 has two spaced-apart second conductive holes 22, and the same material as the second electrode 70 is deposited in each second conductive hole 22 to form two second conductive contacts 42. In this embodiment, setting the second electrode 70 on the substrate 20 as an electromagnet eliminates the need for leads on the second electrode 70, resulting in a simple structure and easy fabrication.

[0060] Please see Figure 4 In another embodiment, the first electrode plate 30 is an electromagnet, the second electrode plate 70 is a permanent magnet, and the conductive contact 40 includes two spaced-apart first conductive contacts 41. The two first conductive contacts 41 are electrically connected to the first electrode plate 30 via two first leads 31, used to apply a DC voltage to the first electrode plate 30 to change its polarity. Correspondingly, the substrate 20 has two spaced-apart first conductive holes 21, each for leading out a corresponding first lead 31. The same material as the corresponding first lead 31 is deposited in each first conductive hole 21 to form two first conductive contacts 41. In this embodiment, setting the second electrode plate 70 on the substrate 20 as an electromagnet eliminates the need for arranging leads on the second electrode plate 70, resulting in a simple structure and easy fabrication.

[0061] Optionally, please see Figure 5 In some embodiments, both the first electrode plate 30 and the second electrode plate 70 are electromagnets; conductive contacts 40 are electrically connected to the first electrode plate 30 and the second electrode plate 70 respectively, for changing the polarity of the electromagnet. The conductive contacts 40 include two spaced-apart first conductive contacts 41, which are electrically connected to the first electrode plate 30 via two first leads 31, for applying a DC voltage to the first electrode plate 30 to change its polarity. Further, the conductive contacts 40 also include two spaced-apart second conductive contacts 42, which are electrically connected to the second electrode plate 70, for applying a DC voltage to the second electrode plate 70 to change its polarity.

[0062] The pressure compensation principle of the MEMS sensor 100 in the above embodiments of this application is described below:

[0063] Strain membrane: The bottom wall of the sealed cavity at the groove 13 and the area projected onto the substrate 10 along the second direction (Z direction) together form a strain membrane. In some embodiments, the strain membrane includes at least a portion of the substrate 10 and the first electrode plate 30.

[0064] When the strain gauge is subjected to pressure along the first direction, it also displaces along the first direction. At this time, a DC voltage can be applied to the first plate 30 and the second plate 70 respectively, so that the charge on the first plate 30 and the second plate 70 is the same, for example, both positive or both negative. This causes the first plate 30 and the second plate 70 to repel each other, causing the strain gauge to displace along the second direction, thereby compensating for the strain gauge deflection and reducing the deflection of the strain gauge, thus reducing the influence of the strain gauge deflection on the linearity of the test results. When the output voltage of the Wheatstone bridge circuit 14 is detected to be the initial value, for example, zero, that is, when the pressure on the strain gauge in the first direction cancels out the deformation force caused by the heating, the magnitude of the applied pressure along the first direction can be calculated based on the magnitude of the voltage input to the first plate 30 and the second plate 70.

[0065] Optionally, when the strain membrane is subjected to pressure along the second direction, it also displaces along the second direction. At this time, a DC voltage can be applied to the first electrode 30 and the second electrode 70, such that the charges on the first electrode 30 and the second electrode 70 are opposite. For example, the charge on the first electrode 30 is positive and the charge on the second electrode 70 is negative, or vice versa. This causes the first electrode 30 and the second electrode 70 to attract each other, resulting in displacement of the strain membrane along the first direction. This compensates for the deflection of the strain membrane, reducing its deflection and minimizing its impact on the linearity of the test results. When the output voltage of the Wheatstone bridge circuit 14 is detected to be at its initial value, such as zero (i.e., the pressure in the second direction on the strain membrane cancels out the deformation force generated by the energized heating), the magnitude of the applied pressure in the second direction can be calculated based on the magnitude of the voltages input to the first electrode 30 and the second electrode 70.

[0066] Furthermore, in some embodiments, a first sealing ring 80 is provided on the first surface 11 of the substrate 10, and a second sealing ring 90 is provided on the surface of the substrate 20 near the substrate 10. The first sealing ring 80 and the second sealing ring 90 are disposed opposite to each other, thereby bonding the substrate 10 and the substrate 20 to form a sealed cavity.

[0067] Please see Figure 6 , Figure 6 This is a flowchart illustrating a method for fabricating a MEMS sensor 100 according to some embodiments of this application. The method for fabricating a MEMS sensor 100 according to embodiments of this application includes at least:

[0068] S10: A substrate 10 is provided, the substrate 10 having opposing first surfaces 11 and second surfaces 12, a Wheatstone bridge circuit 14 is formed on the second surface 12;

[0069] The substrate 10 is a semiconductor substrate 10, such as an SOI (Silicon On Insulator) silicon wafer. See also... Figure 7 Step S10 may include:

[0070] S11: Four sets of varistors 140 are formed on the second surface 12 of the substrate 10;

[0071] The varistor 140 responds to pressure changes applied to the substrate 10 by generating a resistance change, thereby converting the pressure signal into an electrical signal. In some embodiments, each group of varistors 140 includes two parallel and spaced-apart sub-varistors 141. Further, in one embodiment, step S11 further includes forming a heavily doped contact region 143 on the second surface 12 of the substrate 10. The heavily doped contact region 143 may be formed between the sub-varistors 141 for electrically connecting the sub-varistors 141 in the group of varistors 140. The heavily doped contact region 143 is a region that has conductive properties after the semiconductor is doped with metal ions.

[0072] S12: A dielectric layer 15 is formed on the second surface 12 of the substrate 10, and a via is formed in the dielectric layer 15;

[0073] The via is positioned to expose the varistor 140.

[0074] S13: Conductive leads 144 and conductive regions 142 are formed on the dielectric layer 15;

[0075] S14: A passivation layer 16 is formed on the dielectric layer 15, and the passivation layer 16 is patterned to expose the conductive region 142.

[0076] The patterned passivation layer 16 can be patterned by etching.

[0077] S20: A groove 13 is formed on the first surface 11 of the substrate 10, and a first electrode plate 30 is disposed on the bottom wall of the groove 13;

[0078] The method of forming the groove 13 is not limited. For example, the groove 13 can be formed by etching, solution corrosion, or mechanical cutting. The method of forming the first electrode plate 30 can be selected according to the material of the first electrode plate 30, and this application does not impose specific limitations. Step S20 may also include: forming a first lead 31 on each side of the first electrode plate 30;

[0079] S30: A substrate 20 is provided, and a second electrode plate 70 is disposed on one side of the substrate 20;

[0080] Please see Figure 8 In some embodiments, step S30 further includes:

[0081] S31: A first conductive hole 21 and a second conductive hole 22 are formed on the substrate 20 at intervals, and a first lead 31 extends out of the first conductive hole 21 to form a first conductive contact 41.

[0082] S32: A second electrode plate 70 covering the second conductive hole 22 is formed on one side of the substrate 20, and the material of the second electrode plate 70 extends out of the second conductive hole 22 to form a second conductive contact 42.

[0083] In one embodiment, there is one first conductive hole 21 and one second conductive hole 22, which are spaced apart. When the substrate 20 is a glass substrate, the first conductive hole 21 and the second conductive hole 22 can be formed by calcining the substrate 20 using a TGV (Through Glass Via) process.

[0084] Step S30 may further include cleaning the substrate 20 to make the substrate 20 bond more tightly to the substrate 10.

[0085] S40: Cover the groove 13 with the substrate 20 so that the first electrode plate 30 and the second electrode plate 70 are positioned opposite each other.

[0086] After covering the side of the substrate 20 where the second electrode plate 70 is located with the groove 13, a sealed cavity is formed between the substrate 20 and the substrate 10, and the first electrode plate 30 and the second electrode plate 70 are arranged opposite to each other and spaced apart. It is understood that the number and position of the first conductive hole 21 and the second conductive hole 22, as well as the number and position of the first conductive contact 41 and the second conductive contact 42, are related to the principles underlying the aforementioned MEMS sensor 100. The embodiments in this application merely exemplarily illustrate the corresponding principles. Figure 2 The steps included in the fabrication method of the MEMS sensor 100 in this embodiment are similar to those in other embodiments, and will not be repeated here.

[0087] Please see Figure 9 Step S40 includes:

[0088] S41: A first sealing ring 80 is formed on the outer periphery of the first surface 11 of the substrate 10;

[0089] The first sealing ring 80 can be made of chromium, aluminum, copper or gold, and can be formed by sputtering and photolithography.

[0090] S42: A second sealing ring 90 is formed on the outer periphery of one side of the substrate 20;

[0091] S43: Align and bond the first sealing ring 80 and the second sealing ring 90 to make the first lead 31 and the first conductive contact 41 electrically connected, and to form the groove 13 as a sealed cavity.

[0092] After the first sealing ring 80 and the second sealing ring 90 are bonded together, the groove 13 is formed as a sealed cavity between the substrate 20 and the substrate 10, and the first electrode plate 30 and the second electrode plate 70 are arranged opposite to each other to form a parallel electrode capacitor.

[0093] Optionally, please see Figure 10 The flowcharts of other embodiments of this application provide a method for fabricating MEMS sensors, which corresponds to the fabrication of... Figure 5 The MEMS sensor 100 is shown. Specifically, the method includes:

[0094] S101: A varistor 140 and a heavily doped contact region 143 are formed on the second surface 12 of the substrate 10;

[0095] S102: A dielectric layer 15 is formed on the second surface 12 of the substrate 10, and a via is formed on the dielectric layer 15, with the via position corresponding to the position of the varistor 140; a conductive lead 144 is formed on the dielectric layer 15, and a conductive region 142 is formed at the end of the conductive lead 144.

[0096] S103: A passivation layer 16 is formed on the dielectric layer 15, and a via is formed in the passivation layer 16 at the position corresponding to the conductive region 142, so that the conductive region 142 is exposed.

[0097] S104: A groove 13 is formed on the first surface 11 of the substrate 10, and a first electrode plate 30 and a first lead wire 31 electrically connected to the first electrode plate 30 are disposed on the bottom wall of the groove 13; a first sealing ring 80 is formed on the outer periphery of the first surface 11 of the substrate 10.

[0098] S105: Provide a substrate 20, and form two first conductive holes 21 and two second conductive holes 22 on the substrate 20;

[0099] S106: A first conductive contact 41 is formed at each first conductive hole 21, a second electrode plate 70 is formed at the second conductive hole 22, the material of the second electrode plate 70 extends out of each second conductive hole 22 to form a second conductive contact 42, and a second sealing ring 90 is formed on the outer periphery of the substrate 20.

[0100] S107: Align the first sealing ring 80 and the second sealing ring 90 to bond the substrate 10 and the base plate 20 together.

[0101] The MEMS sensor 100 provided in the above embodiments of this application realizes the detection of external pressure by mutual compensation of internal and external pressure, and the strain membrane has small deflection and higher linearity; by monitoring the moment when the output voltage of the Wheatstone bridge circuit 14 is zero, the pressure test can be visualized at the moment when the output voltage of the Wheatstone bridge circuit 14 is zero, which has higher sensitivity.

[0102] It should be noted that the position, material, size, function, etc. of each layer structure involved in the fabrication method of the MEMS sensor 100 described above in this application can be the same as those in the embodiments of the MEMS sensor 100 described above in this application. For details, please refer to the above embodiments, which will not be repeated here.

[0103] The following describes an exemplary embodiment of the MEMS sensor 100 applied to an electronic atomization device.

[0104] Please see also Figure 11 and Figure 12 , Figure 11 Electronic atomizing devices provided in some embodiments of this application; Figure 12 for Figure 11 Functional module diagram of an electronic atomizing device.

[0105] The electronic atomizing device 1000 provided in this application embodiment includes a liquid storage unit 1000A and a control unit 1000B; the liquid storage unit 1000A includes a liquid storage component 200 and an atomizing component 300; the control unit 1000B includes a MEMS sensor 100, a control circuit 400, and a power supply 500. The control unit 1000B also includes a battery cell, etc.

[0106] In some embodiments, the liquid storage component 200 is used to store the aerosol generating matrix. The aerosol generating matrix can be a solid matrix or liquid substance of plant leaves with specific aromas or substances, which can generate aerosols for users to inhale under heating without combustion. The electronic atomizing device 1000 of this application can be used in various fields, such as medical, cosmetic, or recreational inhalation. The liquid storage component 200 has an aerosol inlet end and an aerosol outlet end.

[0107] The atomizing component 300 is disposed in the airflow path from the inlet to the outlet and is in fluid communication with the liquid storage component 200. It is used to atomize the aerosol generating matrix from the liquid storage component 200 into an aerosol. The atomizing component 300 can generate aerosols in any way, such as by ultrasonic vibration or heating to atomize the aerosol generating matrix.

[0108] The MEMS sensor 100 is the MEMS sensor 100 provided in any of the above embodiments. The MEMS sensor 100 is disposed on the airflow channel of the electronic atomizing device 1000, for example, upstream of the atomizing component 300, and is used to detect changes in air pressure within the airflow channel. In this embodiment, the MEMS sensor 100 can serve as an airflow start switch. When a user inhales from the electronic atomizing device 1000, the MEMS sensor 100 can detect the user's inhalation action and output a control signal to the control circuit 400, thereby driving the control circuit to output voltage to the atomizing component 300.

[0109] The power supply 500 can be used to provide voltage to the atomizing assembly 300 and the MEMS sensor 100. The power supply 500 can be a rechargeable battery cell or a replaceable disposable battery cell, etc.

[0110] The control circuit 400 is electrically connected to the atomizing component 300, the MEMS sensor 100, and the power supply 500. The control circuit 400 is used to control the power supply 500 to apply an electrical signal to the first electrode 30 and the second electrode 70 according to the change in output voltage of the MEMS sensor 100 caused by the change in air pressure in the airflow channel. This causes the first electrode 30 and the second electrode 70 to apply a force to the bottom wall of the groove 13, either close to or away from the substrate 20, so that the change in output voltage of the MEMS sensor 100 is less than or equal to a preset threshold, thereby compensating for the drift in the relationship between the resistance of the pressure-sensitive resistor 140 and the pressure caused by the deformation of the substrate 10 under pressure.

[0111] It is understandable that changes in air pressure within the airflow channel will cause changes in the resistance of the pressure-sensitive resistor 140, thereby causing changes in the output voltage Vout of the MEMS sensor 100. The amount of change in the output voltage Vout of the MEMS sensor 100 reflects the magnitude of the air pressure within the airflow channel, i.e., the magnitude of the pressure experienced by the MEMS sensor 100. When the pressure experienced by the MEMS sensor 100 exceeds a certain value, i.e., when the change in the output voltage Vout of the MEMS sensor 100 exceeds a preset threshold, the substrate 10 deforms under pressure, causing a drift in the relationship between the resistance of the pressure-sensitive resistor 140 and the pressure. By applying a voltage to the first electrode 30 and the second electrode 70, the first electrode 30 and the second electrode 70 attract or repel each other, so that when the change in the output voltage Vout of the MEMS sensor 100 is less than or equal to the preset threshold, the drift in the relationship between the resistance of the pressure-sensitive resistor 140 and the pressure caused by the deformation of the substrate 10 is compensated. The preset threshold is the change in output voltage Vout corresponding to the drift of the relationship between the resistance of the varistor 140 and the pressure caused by the pressure deformation of the substrate 10. This can be obtained in advance through experiments.

[0112] In some embodiments, the control circuit 400 is further configured to detect whether the force applied by the first electrode plate 30 to the bottom wall of the groove 13 counteracts the deformation of the bottom wall of the groove 13 caused by air pressure, and when it is detected that the force applied by the first electrode plate 30 to the bottom wall of the groove 13 counteracts the deformation of the bottom wall of the groove 13 caused by air pressure, determine the magnitude of the air pressure based on the electrical signal applied to the first electrode plate 30. The control circuit 400 is also configured to control the atomizing assembly 300 to operate based on the magnitude of the air pressure detected by the MEMS sensor 100.

[0113] The working principle of the MEMS sensor 100 in this embodiment will be explained below in conjunction with the user's inhalation process of the electronic atomizing device 1000:

[0114] When the user begins suction, the MEMS sensor 100 is subjected to a second direction (such as...). Figure 2 Under the pressure applied in the Z direction (vertically upward), the substrate 10 undergoes displacement (or "deformation") in the second direction. Since the Wheatstone bridge circuit 14 includes a varistor 140, the change in the resistance of the varistor 140 causes a change in the voltage output signal Vout of the Wheatstone bridge circuit 14. Based on the change in the voltage output signal Vout, the user's suction action can be detected. When the substrate 10 undergoes displacement in the second direction, a DC voltage is applied to the first plate 30 and the second plate 70, causing the first plate 30 and the second plate 70 to attract each other, causing the first plate 30 to displace in the first direction. This offsets the displacement in the second direction caused by the airflow fluctuation, thus causing the voltage signal output Vout of the Wheatstone bridge circuit 14 to return to 0.

[0115] When the user blows air or inhales, causing airflow fluctuations, positive pressure may be generated inside the electronic atomizing device 1000. Therefore, in addition to displacement in the second direction, the substrate 10 may also be displaced along the first direction.

[0116] When the substrate 10 is subjected to a first direction (e.g.) Figure 2 When pressure (blowing or airflow fluctuation) in the opposite direction of the Z direction (i.e., vertically downward) causes displacement in the first direction, a DC voltage can be applied to the first electrode 30 and the second electrode 70 to cause them to repel each other, thereby causing displacement in the second direction between the first electrode 30 and the substrate 10. This displacement in the first direction is then canceled out by the pressure in the first direction. When the first and second displacements are completely canceled out, the voltage output Vout value of the Wheatstone bridge circuit 14 is 0.

[0117] Therefore, depending on the setting position of the MEMS sensor 100 in this embodiment, it can sensitively detect pressure in any set first and second directions. Compared with the piezoresistive sensors of related technologies, it not only has higher accuracy but also a wider range of applications.

[0118] In the electronic atomizing device 1000 of this embodiment, when subjected to pressure along the second direction, a DC voltage can be applied to the first electrode 30 and the second electrode 70, causing the first electrode 30 and the second electrode 70 to attract each other and displace the first electrode 30 along the first direction, thereby offsetting the displacement of the strain film along the second direction caused by suction. When subjected to pressure along the first direction, a DC voltage can be applied to the first electrode 30 and the second electrode 70, causing the first electrode 30 and the second electrode 70 to repel each other and displace the first electrode 30 along the second direction, thereby offsetting the displacement of the strain film along the first direction caused by airflow disturbance. Therefore, the deflection of the strain film is always small throughout the entire use process, thereby improving the problem that the deformation of the substrate 10 does not change ideally linearly with the pressure, and thus improving the detection accuracy of the MEMS sensor 100 of this embodiment. Furthermore, condensate is easily formed in the airflow channel of the electronic atomizing device 1000; since the first electrode plate 30 and the second electrode plate 70 are sealed in the groove 13, the chance of the first electrode plate 30 and the second electrode plate 70 being corroded or contaminated by condensate can be reduced.

[0119] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between apparatuses or units, and may be electrical, mechanical, or other forms.

[0120] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0121] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A MEMS sensor, characterized in that, include: A substrate having opposing first and second surfaces; the first surface having a groove, and the second surface having a Wheatstone bridge circuit, the bridge arms of the Wheatstone bridge circuit including varistors; A substrate is used to cover the groove to form a sealed cavity; The first electrode plate is disposed on the bottom wall of the groove; The second electrode plate is disposed on the substrate and spaced apart from the first electrode plate; and A conductive contact is disposed on the substrate and / or the base plate, and is electrically connected to at least one of the first electrode plate and the second electrode plate; The first electrode plate and the second electrode plate are configured to repel or attract each other when energized.

2. The MEMS sensor according to claim 1, characterized in that, The first electrode and the second electrode form a parallel electrode capacitor, and the conductive contacts include a first conductive contact electrically connected to the first electrode and a second conductive contact electrically connected to the second electrode.

3. The MEMS sensor according to claim 2, characterized in that, The first electrode plate is disposed on the bottom surface of the groove; the second electrode plate is disposed on the surface of the substrate exposed to the sealed cavity; the first electrode plate and the second electrode plate are disposed opposite to each other.

4. The MEMS sensor according to claim 1, characterized in that, One of the first electrode plate and the second electrode plate includes a permanent magnet material, and the other is an electromagnet; the conductive contact is electrically connected to the electromagnet and is used to change the polarity of the electromagnet.

5. The MEMS sensor according to claim 1, characterized in that, Both the first electrode plate and the second electrode plate are electromagnets; the conductive contacts are electrically connected to the first electrode plate and the second electrode plate respectively, and are used to change the polarity of the electromagnet.

6. The MEMS sensor according to claim 2, characterized in that, The substrate has a first conductive hole and a second conductive hole; the first conductive contact is disposed on the surface of the substrate away from the substrate and is electrically connected to the first electrode plate through the first conductive hole; the second conductive contact is disposed on the surface of the substrate away from the substrate and is electrically connected to the second electrode plate through the second conductive hole.

7. The MEMS sensor according to claim 1, characterized in that, The Wheatstone bridge circuit includes four sets of varistors and four sets of conductive regions. The varistors generate resistance changes in response to pressure changes applied to the substrate, thereby converting the pressure signal into an electrical signal. The conductive regions are used to lead out the electrical signal.

8. The MEMS sensor according to claim 7, characterized in that, The substrate is a semiconductor substrate; each group of varistors includes two parallel and spaced sub-varistors, and a heavily doped contact region formed between the sub-varistors, the heavily doped contact region being used to electrically connect the two parallel and spaced sub-varistors.

9. The MEMS sensor according to claim 8, characterized in that, The varistor and the heavily doped contact region are formed on the substrate, and a dielectric layer is also covered on the substrate, with four sets of conductive regions formed on the dielectric layer.

10. The MEMS sensor according to claim 9, characterized in that, The dielectric layer is further covered with a passivation layer on the side away from the substrate, and the four sets of conductive regions are at least partially exposed in the passivation layer.

11. An electronic atomizing device, characterized in that, include: A liquid storage unit for storing an aerosol generation matrix, the liquid storage unit having an aerosol inlet end and an outlet end; An atomizing component is disposed on the airflow path from the air inlet to the air outlet, and is used to atomize the aerosol generation matrix; The MEMS sensor is the MEMS sensor as described in any one of claims 1-10; the MEMS sensor is disposed on the airflow channel of the electronic atomization device and is used to detect the air pressure change in the airflow channel; A power source for supplying voltage to the atomizing assembly and the MEMS sensor; The control circuit is electrically connected to the power supply, the atomizing component, and the MEMS sensor, respectively. The control circuit is used to apply an electrical signal to the first electrode and the second electrode based on the change in output voltage caused by the change in air pressure in the airflow channel of the MEMS sensor, so that the first electrode and the second electrode repel or attract each other, so that the change in output voltage of the MEMS sensor is less than or equal to a preset threshold.

12. The electronic atomizing device according to claim 11, characterized in that, The preset threshold is zero; the control circuit is also used to detect whether the change in the output voltage of the MEMS sensor is zero; and when the change in the output voltage of the MEMS sensor is detected to be zero, to determine the magnitude of the air pressure based on the electrical signals applied to the first electrode plate and the second electrode plate.

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