MEMS structure, air pump device and electronic equipment

Abstract

The invention discloses an MEMS structure, an air pump device and electronic equipment. The MEMS structure comprises a substrate layer and a piezoelectric layer, the substrate layer comprises a supporting part and a functional part, the functional part comprises a first functional area and a second functional area which are oppositely arranged, the first functional area comprises a first-stage cantilever beam and a second-stage cantilever beam, the first-stage cantilever beam is connected to the supporting part, and the second-stage cantilever beam is connected to the end, away from the supporting part, of the first-stage cantilever beam; the second-stage cantilever beam is in an interdigital shape and can be mutually inserted and intersected with the second functional area; the piezoelectric layer is made of a piezoelectric material, the piezoelectric layer at least covers the surface of the first functional area, and under the condition of electrification, the piezoelectric layer can drive the first-stage cantilever beam and the second-stage cantilever beam to bend upwards or downwards respectively, so that the functional part can enable air flow to flow upwards or downwards. When the MEMS structure is applied to the air pump device, the air pump flow can be provided for the air pump device, and the size of the air pump can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of heat dissipation devices, and more specifically, to a MEMS structure, an air pump device, and an electronic device. Background Art

[0002] With the increasing performance of consumer electronic products such as smart phones, thin and light laptops, and AR / VR devices, the heat generation has increased significantly, putting great heat dissipation pressure on the devices. Traditional heat dissipation methods include active heat dissipation and passive heat dissipation: The active heat dissipation method mainly uses the combination of copper pipes and fans, but has the inherent defects of large volume and high noise; In terms of passive heat dissipation, passive heat dissipation solutions including heat sinks and vapor chambers are mainly used, but the heat dissipation efficiency is low and it is difficult to meet the heat dissipation requirements of high-performance products. Summary of the Invention

[0003] An object of the present application is to provide a new technical solution for a MEMS structure, an air pump device, and an electronic device.

[0004] According to a first aspect of the present application, there is provided a MEMS structure applied to an air pump device, including:

[0005] A base layer, the base layer includes a support portion and a functional portion, the functional portion includes a first functional area and a second functional area arranged oppositely, the first functional area includes a first-level cantilever beam and a second-level cantilever beam, the first-level cantilever beam is connected to the support portion, the second-level cantilever beam is connected to an end of the first-level cantilever beam away from the support portion, and the second-level cantilever beam is finger-shaped and can intersect with the second functional area;

[0006] A piezoelectric layer, the piezoelectric layer is made of a piezoelectric material, the piezoelectric layer at least covers the surface of the first functional area, and when energized, the piezoelectric layer can drive the first-level cantilever beam and the second-level cantilever beam to bend upward or downward respectively, so that the functional portion can make the air flow upward or downward.

[0007] Optionally, the structure of the second functional area is the same as that of the first functional area;

[0008] The piezoelectric layer includes a first piezoelectric area and a second piezoelectric area, the first piezoelectric area covers each of the first-level cantilever beams, and the second piezoelectric area covers each of the second-level cantilever beams;

[0009] Wherein, the first piezoelectric area can drive each of the first-level cantilever beams to bend upward or downward, and the second piezoelectric area can drive each of the second-level cantilever beams to bend upward or downward.

[0010] Optionally, in the energized state of the piezoelectric layer, the functional portion can have an upstroke and a downstroke;

[0011] When the functional part is in the upstroke, the first piezoelectric region moves the first-level cantilever beam from the downward bending state to the upward bending state, and the second piezoelectric region keeps the second-level cantilever beam in the downward bending state all the time, so that the functional part can allow air flow to pass through;

[0012] When the functional part is in the downstroke, the first piezoelectric region moves the first-level cantilever beam from the upward bending state to the downward bending state, and the second piezoelectric region moves the second-level cantilever beam from the downward bending state to the upward bending state, so that the functional part can block the air flow from passing through.

[0013] Optionally, a plurality of the functional parts are provided, and the plurality of functional parts are all arranged on the support part;

[0014] When the first piezoelectric region and the second piezoelectric region are energized, each of the functional parts can make the air flow flow upward or downward simultaneously.

[0015] Optionally, when a first driving voltage is input to the first piezoelectric region and a second driving voltage is input to the second piezoelectric region, the first driving voltage and the second driving voltage can make the upward air flow rate and the downward air flow rate different.

[0016] Optionally, the piezoelectric layer has a top electrode and a bottom electrode, the bottom electrode is grounded, and the top electrode is used to input the first driving voltage and the second driving voltage.

[0017] Optionally, the size of the first-level cantilever beam in its extending direction is greater than or equal to the size of the second-level cantilever beam.

[0018] According to the second aspect of the present application, there is provided an air pump device, including:

[0019] A PCB board and the MEMS structure according to the first aspect, the base layer is arranged on the PCB board, and the piezoelectric layer is electrically connected to the PCB board.

[0020] Optionally, it further includes:

[0021] A cover plate, the cover plate is covered on the side of the MEMS structure away from the PCB board, and a first air hole is arranged at the position of the cover plate corresponding to the functional part;

[0022] A second air hole is arranged at the position of the PCB board corresponding to the functional part, and cavities are respectively formed between the functional part and the cover plate and the PCB board.

[0023] According to the third aspect of the present application, there is provided an electronic device, characterized in that it includes:

[0024] The MEMS structure described in the first aspect; or including,

[0025] The air pump device described in the second aspect.

[0026] For the MEMS structure provided in the present application, the functional part formed by two relatively arranged first functional areas and second functional areas on the base layer intersects with the second functional area through the finger-like secondary cantilever beams, so that it can be used as the structural basis for controlling the air flow when applied to the air pump device.

[0027] The setting of the piezoelectric layer enables at least the first functional area to drive the primary cantilever beam and the secondary cantilever beam to bend upward or downward when powered on, so that it can be used as a driving structure when applied to the air pump device. And based on its structural characteristics and working principle, the inhalation or exhaust stroke of the air pump device is realized, which not only provides the external heat dissipation function of the air pump device, but also reduces the volume of the air pump device, making it applicable to various electronic devices.

[0028] Through the following detailed description of the exemplary embodiments of the present application with reference to the accompanying drawings, other features and advantages of the present application will become clear. Brief Description of the Drawings

[0029] The drawings incorporated in and constituting a part of this specification illustrate embodiments of the present application and, together with the description, are used to explain the principles of the present application.

[0030] Figure 1 It is a schematic diagram of the MEMS structure provided by the present application.

[0031] Figure 2 is Figure 1 The back schematic diagram of the MEMS structure in

[0032] Figure 3 It is a schematic diagram of the structure of the first functional area provided by the present application.

[0033] Figures 4a - 4c It is a schematic diagram of the state of the MEMS structure provided by the present application when in the upward stroke.

[0034] Figures 5a - 5c It is a schematic diagram of the state of the MEMS structure provided by the present application when in the downward stroke.

[0035] Figure 6 It is a waveform diagram of the first driving voltage and the second driving voltage provided by the present application.

[0036] Figure 7 It is a schematic diagram of the structure of the air pump device provided by the present application.

[0037] Description of the Reference Numerals:

[0038] 1. MEMS structure; 11. Substrate layer; 111. Support part; 112. Functional part; 1121. First functional area; 1122. Second functional area; 1123. First-level cantilever beam; 1124. Second-level cantilever beam; 12. Piezoelectric layer; 121. First piezoelectric area; 122. Second piezoelectric area; 123. Electrode pin; 13. Cavity;

[0039] 2. Cover plate; 21. First air hole;

[0040] 3. PCB board; 31. Second air hole. Detailed implementation manners

[0041] Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions and values set forth in these embodiments do not limit the scope of the present application.

[0042] The following description of at least one exemplary embodiment is merely illustrative in nature and in no way serves as a limitation to the present application and its application or use.

[0043] Techniques, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods, and devices should be regarded as part of the specification.

[0044] In all the examples shown and discussed herein, any specific values should be construed as merely exemplary and not as a limitation. Thus, other examples of the exemplary embodiments may have different values.

[0045] It should be noted that: like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, further discussion thereof is not required in subsequent drawings.

[0046] As Figures 1 to 3As shown, according to the first aspect of the present application, a MEMS (Micro-Electro-Mechanical System) structure 1 is provided, which is applied to an air pump device and includes: a base layer 11 and a piezoelectric layer 12. The base layer 11 includes a support portion 111 and a functional portion 112. The functional portion 112 includes a first functional region 1121 and a second functional region 1122 that are oppositely arranged. The first functional region 1121 includes a primary cantilever beam 1123 and a secondary cantilever beam 1124. The primary cantilever beam 1123 is connected to the support portion 111, and the secondary cantilever beam 1124 is connected to one end of the primary cantilever beam 1123 away from the support portion 111. The secondary cantilever beam 1124 is in a finger-like shape and can intersect with the second functional region 1122. The piezoelectric layer 12 is made of a piezoelectric material. The piezoelectric layer 12 covers at least the surface of the first functional region 1121, and when energized, the piezoelectric layer 12 can drive the primary cantilever beam 1123 and the secondary cantilever beam 1124 to bend upward or downward respectively, so that the functional portion 112 can make the air flow upward or downward.

[0047] Specifically, for the MEMS structure 1 provided in this embodiment, the base layer 11 is provided with a support portion 111 mainly used to support the entire structure and a functional portion 112 mainly used for function realization. The base layer 11 can generally be made of materials such as silicon and silicon dioxide. The piezoelectric layer 12 is made of a piezoelectric material, such as PZT (Lead Zirconate Titanate) or AIN (Aluminium Nitride). Based on the inverse piezoelectric effect, after the piezoelectric layer 12 is energized, it can drive the primary cantilever beam 1123 and the secondary cantilever beam 1124 of the functional portion 112 to bend upward or downward by adjusting the driving voltage, so that the functional portion 112 can drive the air flow above or below it to flow in a specific direction. The flow of the air can realize the active heat dissipation function of the air pump device for the electronic device. Compared with traditional heat sinks or heat pipes, it can meet the heat dissipation requirements of high-performance products and has a smaller volume.

[0048] Furthermore, in this embodiment, the functional portion 112 is designed as a first functional region 1121 and a second functional region 1122 that are oppositely arranged. Each first functional region includes a primary cantilever beam 1123 connected to the support portion 111 and a secondary cantilever beam 1124 connected in a finger-like shape to one end of the primary cantilever beam 1123 away from the support portion 111, that is, as Figure 1 and Figure 3As shown in the figure, the first-level cantilever beam 1123 is a single-piece cantilever beam extending from the support portion 111, and the second-level cantilever beam 1124 is a finger-shaped cantilever beam array formed by multiple cantilever beams extending from the free end of the first-level cantilever beam 1123. The finger-shaped second-level cantilever beam 1124 in the first functional area 1121 can be inserted into the second functional area 1122. That is, the second functional area 1122 can be designed to have the same structure as the first functional area 1121, or can only be provided with a finger-shaped structure formed by multiple cantilever beams. This enables when the first functional area 1121 and the second functional area 1122 are arranged opposite to each other, they can be intersected with each other through the finger-shaped structure to form the functional part 112. That is, in the state where the piezoelectric layer 12 is not powered on, the functional part 112 can at least block the majority of the airflows on its upper and lower sides from flowing through each other.

[0049] When the MEMS structure 1 is applied to the air pump device, based on the piezoelectric layer 12 covering at least the surface of the first-level cantilever beam 1123 and the surface of the second-level cantilever beam 1124, the MEMS structure 1 can make the first-level cantilever beam 1123 and the second-level cantilever beam bend upward or downward respectively by applying a specific driving voltage to the piezoelectric layer 12, so as to realize that the functional part 112 drives the airflow to flow downward or upward, that is, realizes the outflow and return flow of the airflow, enabling the air pump device to be used for dissipating heat from the electronic device.

[0050] In the above embodiment, the driving voltages of the piezoelectric layer 12 on the surface of the first-level cantilever beam 1123 and the piezoelectric layer 12 on the surface of the second-level cantilever beam 1124 can be the same or different, so as to realize the same-direction bending or opposite-direction bending of the first-level cantilever beam 1123 and the second-level cantilever beam 1124, and further realize the adjustment of the outflow flow rate and the return flow rate of the airflow. The present application does not limit this. Based on its structural characteristics and working principle, the MEMS structure 1 provided by the present application can improve its heat dissipation efficiency by adjusting the magnitudes of the driving voltages at different positions of the piezoelectric layer 12 when applied to the air pump device, while reducing power consumption and noise, and also reducing the volume of the air pump device.

[0051] Optionally, the second functional area 1122 has the same structure as the first functional area 1121; the piezoelectric layer 12 includes a first piezoelectric area 121 and a second piezoelectric area 122. The first piezoelectric area 121 covers each first-level cantilever beam 1123, and the second piezoelectric area 122 covers each second-level cantilever beam 1124; wherein, the first piezoelectric area 121 can drive each first-level cantilever beam 1123 to bend upward or downward, and the second piezoelectric area 122 can drive each second-level cantilever beam 1124 to bend upward or downward.

[0052] Specifically, in this embodiment, the same structure of the second functional region 1122 and the first functional region 1121 means that the second functional region 1122 also has a first-level cantilever beam 1123 connected to the support portion 111 and a finger-shaped second-level cantilever beam 1124 connected to the end of the first-level cantilever beam 1123 away from the support portion 111, so that the first functional region 1121 and the second functional region 1122 can be plugged into each other through the two second-level cantilever beams 1124. Among them, the sizes of the two first-level cantilever beams 1123 of the first functional region 1121 and the second functional region 1122 may be the same or different, and the sizes of the two second-level cantilever beams 1124 may also be the same or different, which can be specifically designed according to actual needs, and this application does not limit this.

[0053] In addition, in this embodiment, the first piezoelectric region 121 covering each first-level cantilever beam 1123 means that the first piezoelectric region 121 covers the first-level cantilever beams 1123 of the first functional region 1121 and the second functional region 1122, and the second piezoelectric region 122 covering each second-level cantilever beam 1124 means that the second piezoelectric region 122 covers the second-level cantilever beams 1124 of the first functional region 1121 and the second functional region 1122. Based on this, when the above MEMS structure is applied to the air pump structure, the first piezoelectric region into which the first driving voltage V1 is introduced can drive the two first-level cantilever beams 1123 to bend upward or downward, and the second piezoelectric region 122 into which the second driving voltage V2 is introduced can drive the two second-level cantilever beams 1124 to bend upward or downward, so that the piezoelectric layer 12 can drive the entire functional portion 112 to bend upward or downward as a whole to realize the outflow and return of the air flow. In the above embodiment, the upward or downward bending of the first-level cantilever beam 1123 and the second-level cantilever beam 1124 only means that the first piezoelectric region 121 or the second piezoelectric region 122 can drive the first-level cantilever beam 1123 and the second-level cantilever beam 1124 to bend in two different opposite directions to realize the function of the functional portion 112 driving the air flow to flow out and return, and its upward or downward bending state can be flexibly understood according to the placement direction of the MEMS structure 1.

[0054] In addition, the first piezoelectric region 121 and the second piezoelectric region 122 can completely cover the first-level cantilever beam 1123 and the second-level cantilever beam 1124, or can cover a part of the first-level cantilever beam 1123 and the second-level cantilever beam 1124, as long as the purpose of driving the air flow by the functional region can be achieved.

[0055] In addition, the upper and lower surfaces of the piezoelectric layer 12 can generally be regarded as the top electrode and the bottom electrode, and the top electrode and the bottom electrode can be respectively led out to the support portion 111 through wires or conductive materials to form electrode pins 123, so as to facilitate the connection between the MEMS structure 1 and the external circuit.

[0056] Optionally, referring to Figures 4a to 5c , in the energized state, the functional part 112 can have an upward flapping stroke and a downward flapping stroke; when the functional part 112 is in the upward flapping stroke, the first piezoelectric region 121 causes the first-level cantilever beam 1123 to move from the downward-bending state to the upward-bending state, and the second piezoelectric region 122 causes the second-level cantilever beam 1124 to always be in the downward-bending state, so that the functional part 112 can allow air flow to pass through; when the functional part 112 is in the downward flapping stroke, the first piezoelectric region 121 causes the first-level cantilever beam 1123 to move from the upward-bending state to the downward-bending state, and the second piezoelectric region 122 causes the second-level cantilever beam 1124 to move from the downward-bending state to the upward-bending state, so that the functional part 112 can block the air flow from passing through.

[0057] Specifically, in this embodiment, the upward flapping stroke and the downward flapping stroke of the functional part 112 can respectively correspond to the air flow return stroke and the air flow outflow stroke of the air pump device, so as to realize the heat dissipation function of the air pump device for devices such as electronic devices. In one embodiment, both the first functional region 1121 and the second functional region 1122 are multi-level cantilever beams. By applying a first driving voltage V1 to the first piezoelectric region 121 and a second driving voltage V2 to the second voltage region, the bending degree and bending direction of the two first-level cantilever beams 1123 and the second-level cantilever beam 1124 of the first functional region 1121 and the second functional region 1122 are controlled. Among them, the piezoelectric layer 12 usually has a top electrode and a bottom electrode. After grounding the bottom electrode, the top electrode is led out to the support part 111 or other structures through the electrode pin 123, so as to facilitate the control of the driving voltages of the first piezoelectric region 121 and the second piezoelectric region 122.

[0058] In this embodiment, the waveform diagrams of the applied first driving voltage V1 and the second driving voltage V2 are respectively as shown in Figure 6 . During the upward flapping stroke, referring to Figures 4a to 4c shown, as the first driving voltage V1 changes, the first-level cantilever beams 1123 of the first functional region 1121 and the second functional region 1122 gradually change from the downward-bending state to the upward-bending state, while the second driving voltage V2 remains unchanged all the time, so that the second-level cantilever beams 1124 of the first functional region 1121 and the second functional region 1122 always remain in the downward-bending state. During this process, a large number of gaps are formed between the first functional region 1121 and the second functional region 1122, so that the damping of the whole functional part 112 to air is small, and only a small part of the air moves upward with the functional part 112, achieving the purpose of reducing the flow rate of the return air flow.

[0059] During the downward flapping stroke, referring to Figures 5a to 5b, as the first driving voltage V1 changes, the first-level cantilever beams 1123 in the first functional region 1121 and the second functional region 1122 both gradually change from the final state (i.e., the upwardly bent state) in the upward flapping stroke to the downwardly bent state. As the second driving voltage V2 changes, the second-level cantilever beams 1124 in the first functional region 1121 and the second functional region 1122 both change from the final state (i.e., the downwardly bent state) in the upward flapping stroke to the upwardly bent state. During this process, the gap between the first functional region 1121 and the second functional region 1122 is very small, and at this time, the damping of the functional part 112 to air is very large, so that most of the air can move downward with the functional part 112, achieving the purpose of increasing the outflow air flow rate and improving the working efficiency.

[0060] When the above MEMS structure 1 is applied to the air pump structure, the upward flapping stroke and the downward flapping stroke can reciprocate in this way to realize the overall downward flow of the air flow, and further realize the purpose of unidirectional air flow without setting a check valve. And based on its ability to increase the outflow air flow rate and reduce the reflux air flow rate, when the air pump structure is used for heat dissipation of electronic equipment, its heat dissipation efficiency can be improved. In addition, since the MEMS structure operates in the ultrasonic frequency band (>20 kHz), the working noise is small, improving its adaptability to the use environment. In practical applications, the specific directions and magnitudes of the first driving voltage V1 and the second driving voltage V2 can also be designed according to actual needs. For example, its working frequency can be set to the first-order resonance frequency of the cantilever beam to reduce each driving voltage, thereby reducing power consumption. This application does not limit this.

[0061] Optionally, when the first driving voltage V1 is input to the first piezoelectric region 121 and the second driving voltage V2 is input to the second piezoelectric region 122, the first driving voltage V1 and the second driving voltage V2 can make the upward air flow rate and the downward air flow rate different.

[0062] Specifically, when the above MEMS structure is applied to the air pump device, the magnitude of the outflow air flow rate, the magnitude of the reflux air flow rate, and the flow direction of the air flow can all be adaptively adjusted by adjusting the magnitudes and directions of the first driving voltage V1 and the second driving voltage V2. For example, by respectively applying the driving voltages as shown in Figure 6 to the first piezoelectric region 121 and the second piezoelectric region 122, the functional requirements of reducing reflux and increasing flow rate for the air pump device can be achieved.

[0063] Optionally, as shown in Figures 1 to 2 , a plurality of functional parts 112 are provided, and the plurality of functional parts 112 are all provided on the support part 111; when the first piezoelectric region 121 and the second piezoelectric region 122 are energized, each functional part 112 can make the air flow upward simultaneously or downward simultaneously.

[0064] Specifically, in this embodiment, in order to further increase the air flow out volume of the MEMS structure 1, the number of functional parts 112 can be increased according to actual needs. For example Figures 1 to 2 In the MEMS structure 1 in Figures 1 to 2 , four functional parts 112 are provided. The structures of each functional part 112 are the same, and they are respectively arranged at the four sides of the rectangular base layer 11. The rest of the base layer 11 serves as the support part 111 to improve the reliability of the entire structure. Among them, the bottom electrodes of the corresponding piezoelectric layers 12 on each functional part 112 can be grounded, and the top electrodes can be connected in series or in parallel according to actual needs. Finally, multiple electrode pins 123 can be designed to lead out to the support part 111 for easy connection with the circuit. This application does not limit this

[0065] In practical applications, based on heat dissipation, a large volume of air flow is usually required. Therefore, each functional part 112 needs to be synchronized during operation, that is, simultaneously in the upward stroke or simultaneously in the downward stroke. The air flow out direction can be above the base layer 11 or below the base layer 11, and multiple functional parts 112 can also be arranged side by side at intervals on the base layer 11, etc., which is specifically designed according to product needs, improving the design flexibility and the rationality of space occupation

[0066] Optionally, as Figure 2 shown, the support part 111 is provided with through holes, the functional part 112 is located in the through holes, and a cavity 13 is formed on the side of the functional part 112

[0067] Specifically, in this embodiment, the base layer 11 has a certain thickness, that is, when the functional part 112 is arranged in the through hole of the support part 111, one side or both sides of the functional part 112 are cavity 13 structures, which can avoid the influence of the support part 111 on the bending of each part structure of the functional part 112 and improve the reliability of the operation of the functional part 112

[0068] Optionally, as Figure 3 shown, the secondary cantilever beam 1124 includes multiple interdigital fingers arranged at intervals in sequence, and the interval distance between adjacent interdigital fingers is greater than the width of the interdigital finger by 2-4 μm

[0069] Specifically, in practical applications, the secondary cantilever beam 1124 is a structure of multiple interdigital fingers arranged at intervals in sequence. The first functional area 1121 and the second functional area 1122 are intersected by two secondary cantilever beams 1124, so that the functional part 112 can not only block the air flow but also allow the air flow to pass through, thereby enabling the MEMS structure 1 to achieve the purpose of unidirectional air flow and reducing the backflow volume. The distance between adjacent interdigital fingers (such as Figure 3The distance between two adjacent interdigital electrodes in the X direction (in the present invention) is designed to be 2-4 μm greater than the width of the interdigital electrode, so that during the upstroke and downstroke, the bending motions of the two secondary cantilever beams 1124 do not interfere with or collide with each other, nor will the flow rate of the air flowing out be affected due to an excessive gap.

[0070] Optionally, as Figure 3 shown, the size of the primary cantilever beam 1123 in its extending direction is greater than or equal to the size of the secondary cantilever beam 1124.

[0071] Specifically, in this embodiment, the size of the primary cantilever beam 1123 in its extending direction (refer to the Y direction in Figure 3 ) is designed to be greater than or equal to the size of the secondary cantilever beam 1124, so that the structural reliability of the entire functional part 112 is relatively high, and the control of the outflow rate of the air flow can be ensured. Of course, the size difference between the two should not be too large to avoid an unsatisfactory effect on reducing the reflux flow rate.

[0072] As Figure 7 shown, according to the second aspect of the present application, a gas pump device is provided, including: a PCB board 3 and the MEMS structure 1 of the first aspect, the base layer 11 is disposed on the PCB board 3, and the piezoelectric layer is electrically connected to the PCB board 3.

[0073] Specifically, in this embodiment, the MEMS structure 1 is used as the main functional structure of the gas pump device, while the PCB board 3 is conducive to applying a driving voltage to the piezoelectric layer. Through circuit design, it is also convenient to adjust the magnitude or direction of the driving voltage in different regions of the piezoelectric layer. Among them, the PCB board 3 can be a separately provided circuit board, or it can be a circuit board in an electronic device when the gas pump device is applied to the electronic device, and can be specifically designed according to actual requirements.

[0074] Optionally, the gas pump device further includes: a cover plate 2, the cover plate 2 is covered on the side of the MEMS structure 1 away from the PCB board 3, and a first air hole 21 is provided at a position corresponding to the functional part 112 on the cover plate 2; a second air hole 31 is provided at a position corresponding to the functional part 112 on the PCB board 3, and cavities 13 are respectively formed between the functional part 112 and the cover plate 2 and the PCB board 3.

[0075] Specifically, the cover plate 2 and the PCB board 3 can provide a certain degree of protection for the MEMS structure 1, and the arrangement of the first air holes 21 and the second air holes 31 can ensure the inflow and outflow directions of the air flow, so as to achieve the heat dissipation function of the air pump device. Among them, the number, size, shape, etc. of the first air holes 21 and the second air holes 31 can be designed in a matching manner according to the situation of the functional part 112. The size of the first air holes 21 and the second air holes 31 can usually be designed to be slightly larger than the edge of the functional part 112 to ensure the smoothness and flow rate of the air flow. In addition, the cavity 13 between the functional part 112 and the cover plate 2 and the PCB board 3 can ensure that the bending of each part of the functional part 112 is not interfered by the two devices, improving the reliability of the structure.

[0076] According to the third aspect of the present application, there is provided an electronic device, including: the MEMS structure 1 of the first aspect; or including the air pump device of the second aspect.

[0077] Specifically, in this embodiment, applying the MEMS structure 1 provided in the first aspect or the air pump device provided in the second aspect to the electronic device, due to its advantages of high heat dissipation efficiency, low power consumption, low noise, small volume, etc., the electronic device can meet the design requirements of high heat dissipation and miniaturization. Among them, the electronic device can be a smart phone, a thin and light notebook, an AR / VR device, etc., and the present application does not limit this.

[0078] In the above embodiments, the differences between the embodiments are mainly described. As long as the different optimization features between the embodiments are not contradictory, they can be combined to form a better embodiment. For the sake of brevity of the description, they will not be elaborated here.

[0079] Although some specific embodiments of the present application have been described in detail by way of examples, those skilled in the art should understand that the above examples are only for illustration purposes and not for limiting the scope of the present application. Those skilled in the art should understand that the above embodiments can be modified without departing from the scope and spirit of the present application. The scope of the present application is defined by the appended claims.

Claims

1. A MEMS structure, applied to an air pump device, characterized in that: include: A base layer, the base layer comprising a support portion and a functional portion, the functional portion comprising a first functional area and a second functional area arranged opposite to each other, the first functional area comprising a primary cantilever beam and a secondary cantilever beam, the primary cantilever beam being connected to the support portion, the secondary cantilever beam being connected to an end of the primary cantilever beam away from the support portion, the secondary cantilever beam being in a forked finger shape and being able to intersect with the second functional area; A piezoelectric layer, wherein the piezoelectric layer is made of a piezoelectric material and covers at least the surface of the first functional area. When powered on, the piezoelectric layer can drive the primary cantilever beam and the secondary cantilever beam to bend upward or downward respectively, so that the functional part can cause the airflow to flow upward or downward.

2. The MEMS structure according to claim 1, characterized in that: The second functional area has the same structure as the first functional area; The piezoelectric layer includes a first piezoelectric region and a second piezoelectric region, the first piezoelectric region covers each of the first-level cantilever beams, and the second piezoelectric region covers each of the second-level cantilever beams; The first piezoelectric region can drive each of the primary cantilever beams to bend upward or downward, and the second piezoelectric region can drive each of the secondary cantilever beams to bend upward or downward.

3. The MEMS structure according to claim 2, characterized in that: When the piezoelectric layer is powered on, the functional part can have an upward stroke and a downward stroke; When the functional part is in the upward stroke, the first piezoelectric area causes the primary cantilever beam to move from a downward bending state to an upward bending state, and the second piezoelectric area causes the secondary cantilever beam to always be in a downward bending state, so that the functional part can allow airflow to pass through; When the functional part is in the downward stroke, the first piezoelectric area causes the primary cantilever beam to move from an upward bending state to a downward bending state, and the second piezoelectric area causes the secondary cantilever beam to move from a downward bending state to an upward bending state, so that the functional part can block the passage of airflow.

4. The MEMS structure according to claim 2, characterized in that: There are multiple functional parts, and the multiple functional parts are all arranged on the supporting part; When the first piezoelectric region and the second piezoelectric region are energized, the functional portions can cause airflow to flow upward or downward simultaneously.

5. The MEMS structure according to claim 2, characterized in that: When a first driving voltage is input to the first piezoelectric region and a second driving voltage is input to the second piezoelectric region, the first driving voltage and the second driving voltage can make the upward airflow amount and the downward airflow amount different.

6. The MEMS structure according to claim 5, characterized in that: The piezoelectric layer has a top electrode and a bottom electrode, the bottom electrode is grounded, and the top electrode is used to pass the first driving voltage and the second driving voltage.

7. The MEMS structure according to claim 1, characterized in that: The size of the primary cantilever beam in its extension direction is greater than or equal to the size of the secondary cantilever beam.

8. An air pump device, characterized in that: include: A PCB board and a MEMS structure as described in any one of claims 1 to 7, wherein the base layer is arranged on the PCB board, and the piezoelectric layer is electrically connected to the PCB board.

9. An air pump device according to claim 8, characterized in that: Also includes: A cover plate, the cover plate is arranged on a side of the MEMS structure away from the PCB board, and a first air hole is arranged at a position of the cover plate corresponding to the functional part; The PCB board is provided with a second air hole at a position corresponding to the functional part, and cavities are respectively formed between the functional part, the cover plate and the PCB board.

10. An electronic device, characterized in that: include: The MEMS structure according to any one of claims 1 to 7; or include, An air pump device as claimed in claim 8 or 9.

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