Heat dissipation structure, electronic device

Abstract

This application provides a heat dissipation structure and an electronic device. It relates to the field of heat dissipation technology for electronic devices. The heat dissipation structure includes a housing and a vibration module; the housing has an air inlet and an air outlet; the vibration module includes a first piezoelectric vibrating diaphragm and a second piezoelectric vibrating diaphragm, one end of which is fixed and the other end is suspended. A gap exists between the suspended portions of the two piezoelectric vibrating diaphragms. A first air duct is formed in the space on one side of the first and second piezoelectric vibrating diaphragms, and a second air duct is formed in the space on the other side of the first and second piezoelectric vibrating diaphragms. At least a portion of the gap is opposite to the air outlet. In this application, at least two piezoelectric vibrating diaphragms are cantilever beam structures. When the two cantilever beam structures vibrate under the drive of alternating current, they have a large amplitude, meaning the effective working area of ​​the two piezoelectric vibrating diaphragms is large, thereby increasing the airflow.

Description

Technical Field

[0001] This application relates to the field of heat dissipation technology for electronic devices, and more particularly to a heat dissipation structure and an electronic device that may include the heat dissipation structure. Background Technology

[0002] With the increasing power consumption of electronic devices (such as mobile phones, tablets, and laptops), heat dissipation is gradually becoming a bottleneck. Taking mobile phones as an example, heat dissipation capacity has a significant impact on phone performance, especially in scenarios involving prolonged heavy gaming, video recording, or multiple applications running consecutively. In these situations, the phone's casing may reach a temperature control threshold, triggering thermal management. This causes the chip to limit its frequency and reduce power consumption to control the casing temperature, sacrificing chip performance. Improving heat dissipation capacity can release more chip computing power and performance.

[0003] Currently, mobile phone heat dissipation widely adopts passive and active heat dissipation solutions. For example, passive heat dissipation solutions use vacuum chamber (VC) heat dissipation technology and graphite film heat dissipation, which can diffuse the heat of chips and other components in the plane of the mobile phone, enhancing the natural convection and radiation heat transfer of the mobile phone screen and shell. However, the limits of passive heat dissipation have been basically reached. Another example is active heat dissipation solutions, which use piezoelectric vibrating films for heat dissipation. However, the existing piezoelectric vibrating film heat dissipation structures have low airflow and limited heat dissipation capacity, which still cannot meet the usage requirements of electronic devices. Summary of the Invention

[0004] This application provides a heat dissipation structure and an electronic device including the heat dissipation structure. The purpose is to provide a heat dissipation structure that can increase airflow and enhance heat dissipation effect.

[0005] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0006] Firstly, this application provides a heat dissipation structure that can be applied in electronic devices, such as mobile phones, tablets, and other terminal devices.

[0007] The heat dissipation structure provided in this application includes a housing and at least one vibration module disposed within the housing. The housing has an air inlet and an air outlet. Each vibration module includes a first piezoelectric vibrating membrane and a second piezoelectric vibrating membrane. Both the first and second piezoelectric vibrating membranes include a fixed portion and a cantilever portion. The fixed portions of both the first and second piezoelectric vibrating membranes are connected to the housing. The cantilever portions of both the first and second piezoelectric vibrating membranes are suspended. The surface of the cantilever portion of the first piezoelectric vibrating membrane away from the fixed portion is a first end face, and the surface of the cantilever portion of the second piezoelectric vibrating membrane away from the fixed portion is a second end face. The first and second end faces are arranged opposite to each other and have a gap between them. A first air duct is formed in the space within the housing located on one side of the first and second piezoelectric vibrating membranes, and a second air duct is formed in the space within the housing located on the other side of the first and second piezoelectric vibrating membranes. The gap connects the first and second air ducts. The air inlet and the air outlet are connected through the first and second air ducts, and the gap is arranged opposite to the air outlet.

[0008] The vibration module provided in this application includes a first piezoelectric vibrating membrane and a second piezoelectric vibrating membrane. Since both the first and second piezoelectric vibrating membranes contain suspended cantilever portions, that is, both the first and second piezoelectric vibrating membranes are cantilever beam structures, the two cantilever beam structures have a large amplitude when vibrating under the drive of alternating current, that is, the two piezoelectric vibrating membranes have a large effective working area; and since there is a gap between the first end face of the cantilever portion of the first piezoelectric vibrating membrane away from the fixed portion and the second end face of the cantilever portion of the second piezoelectric vibrating membrane away from the fixed portion, and this gap connects the first air duct and the second air duct. For example, when the two piezoelectric vibrating diaphragms vibrate towards the second air duct, they can squeeze the air in the second air duct, forming a vortex that flows towards the first air duct, and a jet that flows out from the air outlet. The vortex can draw more air into the first air duct from the air inlet. The air drawn into the first air duct can be ejected through the gap and the air outlet. The vortex can increase the air volume and improve the heat dissipation efficiency. Furthermore, the two piezoelectric vibrating diaphragms, which have a large effective working area, can also increase the air volume in conjunction with the vortex.

[0009] Because the gap and the air outlet are positioned opposite each other, the fluid flowing out of the gap can quickly flow out through the air outlet. This shortens the fluid flow path and reduces fluid flow loss. Consequently, the first piezoelectric vibrating diaphragm and the second piezoelectric vibrating diaphragm can increase the airflow of the heat dissipation structure when driven by the same voltage.

[0010] In one feasible approach, the height of the second air duct is less than the height of the first air duct.

[0011] The second air duct in this application example can be understood as a kind of air-gathering duct. When the two piezoelectric diaphragms vibrate up and down, the air-gathering duct and the gap can form a vortex. This vortex can draw more air from the air inlet into the first air duct (the first air duct can be called the air-drawing duct). When the height of the second air duct is less than the height of the first air duct, it is easier to form a vortex and increase the air volume.

[0012] When the two piezoelectric diaphragms vibrate downwards (towards the second air duct), a strong vortex can be formed in the first air duct because the height of the second air duct is less than that of the first air duct. This strong vortex can draw more air from the inlet into the first air duct, increasing the airflow. When the two piezoelectric diaphragms vibrate upwards (towards the first air duct), the air in the first air duct can quickly replenish the second air duct because the height of the second air duct is less than that of the first air duct. This prepares the air for the next downward movement of the piezoelectric diaphragms and also prevents the air from the outlet from flowing back into the second air duct. Thus, this heat dissipation structure is a structure with unidirectional fluid flow.

[0013] In one possible implementation, at least one of the first piezoelectric vibrating film or the second piezoelectric vibrating film includes a semiconductor substrate, and a first electrode, a piezoelectric layer and a second electrode disposed on the semiconductor substrate, the piezoelectric layer being located between the first electrode and the second electrode.

[0014] In this application example, the first electrode, the piezoelectric layer, and the second electrode are integrated on a semiconductor substrate, such as a silicon substrate. In this case, the first piezoelectric vibrating film or the second piezoelectric vibrating film can be fabricated using micro-electro-mechanical system (MEMS) technology.

[0015] When using piezoelectric diaphragms with MEMS technology, the thickness or length of the piezoelectric diaphragm is small. This allows for a reduction in the overall size of the heat dissipation structure, enabling it to be used in small electronic devices or electronic devices with limited installation space.

[0016] Alternatively, it can be understood that because the size of the piezoelectric vibrating diaphragm is compressed, more piezoelectric vibrating diaphragms can be set within a unit volume. As the number of piezoelectric vibrating diaphragms increases, the effective working area increases, the air volume also increases, and the heat dissipation effect is further improved.

[0017] In one feasible approach, the semiconductor substrate of the fixed portion and the semiconductor substrate of the cantilever portion are integrated into a single structure.

[0018] In one feasible approach, the thickness of the semiconductor substrate of the fixed portion is greater than the thickness of the semiconductor substrate of the cantilever portion, and the fixed portion is connected to the housing via an adhesive layer.

[0019] In some feasible processes, a semiconductor wafer is obtained, and an epitaxial growth process is used to fabricate a first electrode, a piezoelectric layer, and a second electrode on the semiconductor wafer. Then, the semiconductor wafer is locally etched to reduce the local thickness. The thicker part can be used as a fixed part and fixedly connected to the shell, while the thinner part can be used as a cantilever part.

[0020] In one possible implementation, the semiconductor substrate includes at least one of a silicon substrate, a germanium substrate, a germanium-silicon substrate, a gallium nitride substrate, or an indium gallium arsenide substrate.

[0021] When using at least one of the silicon substrate, germanium substrate, germanium-silicon substrate, gallium nitride substrate, or indium gallium arsenide substrate described above, a piezoelectric vibrating film can be fabricated using MEMS technology, thereby obtaining a piezoelectric vibrating film with a smaller size.

[0022] Using a semiconductor substrate as the cantilever part, the semiconductor substrate is flexible and has a large amplitude when vibrating, which can increase the air volume.

[0023] In one possible configuration, the first electrode, the piezoelectric layer, and the second electrode are disposed on the side of the cantilever portion facing the first air duct.

[0024] Since the height of the first air duct is greater than the height of the second air duct, placing the first electrode, piezoelectric layer, and second electrode on the side of the cantilever facing the first air duct, compared to placing them on the side facing the second air duct, can prevent the stacked first electrode, piezoelectric layer, and second electrode from interfering with other structural components, such as the shell, when the piezoelectric vibrating membrane vibrates.

[0025] In one possible implementation, the housing includes a top cover, side plates, and a bottom plate, which are connected to form a chamber for accommodating at least one vibration module.

[0026] For example, the top cover, side panels, or bottom panel can be made of at least one of metal or plastic.

[0027] The top cover, side panels, and bottom plate can be a single molded structure, or they can be connected by a connecting structure, such as by using an adhesive layer.

[0028] In one possible implementation, at least one of the top cover, side plate, or bottom plate is a circuit board; the first piezoelectric vibrating diaphragm and the second piezoelectric vibrating diaphragm are electrically connected to the circuit board.

[0029] When the top cover, side plate, or bottom plate uses a circuit board, the piezoelectric diaphragm can be connected to the circuit board, and the circuit board can be connected to the driver located outside the heat dissipation structure. This simplifies the electrical connection wiring structure between the piezoelectric diaphragm and the driver and avoids wiring redundancy.

[0030] In one feasible approach, the base plate is a circuit board, and the air outlet is located on the circuit board.

[0031] In some applications, the driver used to apply voltage to the first and second piezoelectric diaphragms is located closer to the base plate than the top cover of the housing. Consequently, the base plate can be a circuit board, and the air outlet is located on the base plate.

[0032] In one possible implementation, the air outlets comprise multiple outlets, which are spaced apart along a direction parallel to the direction of the gap extension.

[0033] In this example, since the base plate with the air outlet is a circuit board, in order to avoid the air outlet from affecting the wiring of the circuit board, multiple air outlets can be set, and the multiple air outlets can be set at intervals so that the air outlets can avoid the wiring.

[0034] In one feasible approach, an air inlet is provided on the top cover.

[0035] For example, the air inlet and the gap are arranged opposite each other; another example is that the air inlet and the gap are staggered along the arrangement direction of the first piezoelectric vibrating membrane and the second piezoelectric vibrating membrane.

[0036] In some implementations, the air inlet on the top cover can be one or multiple.

[0037] In one feasible approach, an air inlet is provided on the side panel.

[0038] For example, an air inlet can be opened on one of the side panels; or, for example, air inlets can be opened on both opposite side panels.

[0039] In one possible implementation, at least one vibration module includes an adjacent first vibration module and a second vibration module, the first vibration module and the second vibration module being arranged along the length of the housing, and the first piezoelectric diaphragm of the second vibration module and the second piezoelectric diaphragm of the first vibration module being connected.

[0040] This can be understood as follows: when the arrangement direction of the first vibrating membrane group and the second vibrating module is parallel to the arrangement direction of the first piezoelectric vibrating membrane and the second piezoelectric vibrating membrane, the first piezoelectric vibrating membrane of the second vibrating module and the second piezoelectric vibrating membrane of the first vibrating module can be connected.

[0041] For example, when the piezoelectric vibrating film is fabricated using MEMS technology, the substrates of the first and second piezoelectric vibrating films of the second vibration module can be an integral structure, that is, the first and second piezoelectric vibrating films of the second vibration module are fabricated using a single substrate. This allows for further reduction in the size of the piezoelectric vibrating film and compresses the overall size of the heat dissipation structure.

[0042] In one possible implementation, at least one vibration module includes an adjacent third vibration module and a fourth vibration module, the third vibration module and the fourth vibration module being arranged along the width direction of the housing, with a gap between the first piezoelectric vibrating membrane of the fourth vibration module and the first piezoelectric vibrating membrane of the third vibration module; and a gap between the second piezoelectric vibrating membrane of the fourth vibration module and the second piezoelectric vibrating membrane of the third vibration module.

[0043] When the third and fourth vibration modules are arranged along the width of the shell, in order to avoid mutual interference between the first piezoelectric vibration membrane of the third vibration module and the first piezoelectric vibration membrane of the fourth vibration module during vibration, a gap can be made between the first piezoelectric vibration membrane of the fourth vibration module and the first piezoelectric vibration membrane of the third vibration module.

[0044] Similarly, to prevent the second piezoelectric diaphragm of the third vibration module and the second piezoelectric diaphragm of the fourth vibration module from interfering with each other during vibration, there is a gap between the second piezoelectric diaphragm of the fourth vibration module and the second piezoelectric diaphragm of the third vibration module.

[0045] For example, the first piezoelectric vibration film of the third vibration module and the first piezoelectric vibration film of the fourth vibration module both include: a semiconductor substrate; a first electrode, a piezoelectric layer and a second electrode disposed on the semiconductor substrate, with the piezoelectric layer located between the first electrode and the second electrode; the semiconductor substrate of the first piezoelectric vibration film of the third vibration module has a gap with the semiconductor substrate of the first piezoelectric vibration film of the fourth vibration module; the semiconductor substrate of the second piezoelectric vibration film of the third vibration module has a gap with the semiconductor substrate of the second piezoelectric vibration film of the fourth vibration module.

[0046] In one achievable manner, at least one vibration module includes an adjacent first vibration module and a second vibration module; the cantilever portion of the first piezoelectric vibrating membrane of the second vibration module extends in the opposite direction to the cantilever portion of the second piezoelectric vibrating membrane of the first vibration module, that is, the cantilever portions of the first piezoelectric vibrating membrane of the second vibration module and the cantilever portions of the second piezoelectric vibrating membrane of the first vibration module are arranged back-to-back; both the first and second piezoelectric vibrating membranes of the second and first vibration modules include: a semiconductor substrate; a first electrode, a piezoelectric layer, and a second electrode disposed on the semiconductor substrate, the piezoelectric layer being located between the first and second electrodes; the semiconductor substrate of the first piezoelectric vibrating membrane of the second vibration module and the semiconductor substrate of the second piezoelectric vibrating membrane of the first vibration module are integrally structured.

[0047] That is, the first piezoelectric vibrating film of the second vibration module and the second piezoelectric vibrating film of the first vibration module are fabricated using a single substrate. In this way, the size of the piezoelectric vibrating film can be further reduced, thereby compressing the size of the entire heat dissipation structure.

[0048] In one possible implementation, at least one vibration module includes an adjacent third vibration module and a fourth vibration module; the cantilever portion of the first piezoelectric vibration film of the third vibration module extends in the same direction as the cantilever portion of the first piezoelectric vibration film of the fourth vibration module; the first piezoelectric vibration film of the third vibration module and the first piezoelectric vibration film of the fourth vibration module each include: a semiconductor substrate; a first electrode, a piezoelectric layer and a second electrode disposed on the semiconductor substrate, the piezoelectric layer being located between the first electrode and the second electrode; the semiconductor substrate of the first piezoelectric vibration film of the third vibration module and the semiconductor substrate of the first piezoelectric vibration film of the fourth vibration module have a gap.

[0049] This avoids mutual interference between the first piezoelectric diaphragm of the third vibration module and the first piezoelectric diaphragm of the fourth vibration module during vibration.

[0050] Secondly, this application provides an electronic device including a heat-generating component and a heat dissipation structure as described in any of the above implementations. For example, the heat-generating component may be at least one of a chip or a battery.

[0051] Because the electronic device in this application includes the heat dissipation structure in any of the above implementations, in this heat dissipation structure, both the first and second piezoelectric vibrating membranes are cantilever beam structures. When the two cantilever beam structures vibrate under the drive of alternating current, they have a large amplitude, meaning that the effective working area of ​​the two piezoelectric vibrating membranes is large. In addition, there is a gap between the two piezoelectric vibrating membranes, and this gap connects the first and second air ducts. For example, when the two piezoelectric vibrating membranes vibrate towards the second air duct, they can squeeze the air in the second air duct, forming an upward vortex and a jet flowing out from the air outlet. The formed vortex can draw more air into the first air duct from the air inlet. The air drawn into the first air duct can be ejected through the gap and the air outlet, and the formed vortex can increase the airflow.

[0052] Furthermore, the gap is positioned opposite to the air outlet, allowing the fluid flowing out of the gap to quickly exit through the air outlet. This shortens the fluid flow path and reduces fluid flow loss. Consequently, the first and second piezoelectric vibrating diaphragms, driven by the same voltage, can increase the airflow of the heat dissipation structure.

[0053] Therefore, the electronic device provided in this application can quickly dissipate heat from heat-generating components using a heat dissipation structure, such as cooling chips. Because the chip can be cooled quickly, more chip computing power and performance can be released.

[0054] In one possible implementation, the heat-generating component is located at the air inlet of the heat dissipation structure, or at the air outlet of the heat dissipation structure.

[0055] That is, in one example, the heating element can be placed near the air inlet, and in another example, it can be placed near the air outlet.

[0056] In one possible implementation, the electronic device further includes a driver, with the first and second piezoelectric diaphragms connected to the driver, the driver being used to drive the first and second piezoelectric diaphragms to vibrate in the same direction.

[0057] For example, when the first piezoelectric vibrating diaphragm vibrates in the direction of the first air duct, the second piezoelectric vibrating diaphragm also vibrates in the direction of the first air duct, such as the two piezoelectric vibrating diaphragms vibrating in phase or having a phase difference. Attached Figure Description

[0058] Figure 1 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0059] Figure 2 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application;

[0060] Figure 3This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0061] Figure 4 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0062] Figure 5 This is a schematic diagram illustrating the fluid motion principle of a heat dissipation structure provided in an embodiment of this application;

[0063] Figure 6 This is a schematic diagram illustrating the fluid motion principle of a heat dissipation structure provided in an embodiment of this application;

[0064] Figure 7 A flow field simulation diagram of a heat dissipation structure provided in an embodiment of this application;

[0065] Figure 8 An airflow curve of a heat dissipation structure provided in an embodiment of this application;

[0066] Figure 9 An airflow curve of a heat dissipation structure provided in an embodiment of this application;

[0067] Figure 10 This is a schematic diagram of the structure of the piezoelectric vibrating diaphragm provided in the embodiments of this application;

[0068] Figures 11 to 14 This is a schematic diagram of the structure corresponding to the method for preparing the piezoelectric vibrating membrane provided in the embodiments of this application;

[0069] Figure 15 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0070] Figure 16 A power consumption curve of a heat dissipation structure provided in an embodiment of this application;

[0071] Figure 17 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0072] Figure 18 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0073] Figure 19 This is a schematic diagram of the structure of a circuit board provided in an embodiment of this application;

[0074] Figure 20 This is a schematic diagram of the structure of a circuit board provided in an embodiment of this application;

[0075] Figure 21 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0076] Figure 22 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0077] Figure 23 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0078] Figure 24 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0079] Figure 25 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0080] Figure 26 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0081] Figure 27 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0082] Figure 28 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0083] Figure 29 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application;

[0084] Figures 30 to 32 This is a schematic diagram of the structure corresponding to the method for preparing the piezoelectric vibrating membrane provided in the embodiments of this application;

[0085] Figure 33 This is a schematic diagram of the structure of multiple vibrating diaphragm assemblies provided in the embodiments of this application;

[0086] Figure 34 This is a schematic diagram of the structure of multiple vibrating diaphragm assemblies provided in the embodiments of this application;

[0087] Figure 35 This is a schematic diagram of a heat dissipation structure provided in an embodiment of this application.

[0088] Figure label:

[0089] 100 - Display screen; 200 - Back cover; 300 - Mid-frame; 400 - Battery; 500 - Circuit board; 601 - First chip; 602 - Second chip; 700 - Protective cover; 800 - Heat dissipation structure;

[0090] 1-Housing; 2-Vibration module; 3-Gap; 4-First air duct; 5-Second air duct; 6-Adhesive layer; 7-Lead wire;

[0091] 101-Air inlet; 1011-First air inlet; 1012-Second air inlet; 102-Air outlet; 21, 211, 212, 213-First piezoelectric vibrating film; 22, 221, 223-Second piezoelectric vibrating film; 201-Semiconductor substrate; 202-First electrode; 203-Piezoelectric layer; 204-Second electrode;

[0092] 11-Top cover; 12-Side panel; 13-Bottom plate, circuit board. Detailed Implementation

[0093] This application provides an electronic device, such as a mobile phone, tablet, laptop, smart home device, smart wearable device (e.g., smartwatch, smart bracelet, smart glasses, smart helmet), virtual reality (VR) electronic device, augmented reality (AR) electronic device, etc. The electronic device can also be a handheld device with wireless communication capabilities, a computing device or other processing device connected to a wireless modem, an in-vehicle device, an electronic device in a 5G network, or an electronic device in a future evolved public land mobile network (PLMN), etc. This application does not limit the scope of this electronic device.

[0094] like Figure 1 As shown in the embodiment of this application, taking a mobile phone as an example, the electronic device may include a display screen 100, a back cover 200 located on the back of the display screen 100 (distributed opposite to the display surface of the display screen 100), and a mid-frame 300 located between the display screen 100 and the back cover 200. The mid-frame 300 can support the display screen 100.

[0095] The display screen 100 can be a liquid crystal display (LCD), an organic light emitting diode (OLED) display, a micro (or mini) light-emitting diode (LED) display, or a quantum dot light-emitting diode (QLED) display, etc. This application does not limit the type of the above-mentioned display screen.

[0096] The aforementioned electronic device may also include at least one of the following: a processor electrically connected to the display screen 100, a sensor, a memory, a charging management module, a power management module, an antenna, a mobile communication module, a wireless communication module, an audio module, a speaker, a receiver, a microphone, a headphone jack, and a camera electrically connected to the processor.

[0097] like Figure 1 The electronic device may also include a battery 400, which can power some components within the electronic device. The battery 400 is disposed between the display screen 100 and the rear cover 200.

[0098] See Figure 1 The electronic device may also include a circuit board 500, on which electronic components such as the processor, memory, charging management module, and power management module in the above example may be integrated.

[0099] Figure 2 An example diagram of the internal structure of an electronic device is shown.

[0100] In this example, chips are provided on opposite sides of the circuit board 500. For example, a first chip 601 is provided on the side of the circuit board 500 facing the display screen 100, and a second chip 602 is provided on the side of the circuit board 500 facing the back cover 200. In some examples, a protective cover 700 can be provided on the chip to protect it.

[0101] As the computing power and performance of chips increase, the heat generated gradually increases. In order to quickly dissipate heat from the chips, this application provides some heat dissipation structures 800. For example, the heat dissipation structure 800 can be set on the first chip 601, or it can be set on the protective cover 700 of the second chip 602.

[0102] In other examples, the heat dissipation structure 800 of this application can dissipate heat from other heat-generating components, such as batteries.

[0103] like Figure 3 As shown, Figure 3 This is a cross-sectional view of a heat dissipation structure 800 as exemplified in this application.

[0104] The heat dissipation structure 800 includes: a housing 1, and a vibration module 2 disposed within the housing 1. The vibration module 2 can be one or multiple. Figure 3An example of a vibration module 2 is provided. An air inlet 101 and an air outlet 102 are provided on the housing 1; any vibration module 2 includes a first piezoelectric vibrating diaphragm 21 and a second piezoelectric vibrating diaphragm 22. The first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 can be arranged side by side along a direction perpendicular to the thickness direction of the housing 1. For example, if the thickness direction of the housing 1 is the Z direction, the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 can be arranged along a Y direction perpendicular to the Z direction.

[0105] The heat dissipation structure 800 in this application example has a housing 1 that can be a hexahedral structure, including the housing thickness, housing length, and housing width. For example, see... Figure 3 The thickness of the housing can be represented by the Z-direction, the length by the Y-direction, and the width by the X-direction. In other examples, the housing 1 of the heat dissipation structure 800 can be other shapes, such as a circular structure or an elliptical structure.

[0106] See Figure 3 The first piezoelectric vibrating diaphragm 21 includes a fixed part M1 and a cantilever part N1. The fixed part M1 of the first piezoelectric vibrating diaphragm 21 is connected to the housing 1. For example, the fixed part M1 of the first piezoelectric vibrating diaphragm 21 is fixedly connected to the housing 1. The cantilever part N1 of the first piezoelectric vibrating diaphragm 21 is suspended and not connected to other structural components.

[0107] See Figure 3 The second piezoelectric vibrating membrane 22 includes a fixed part M2 and a cantilever part N2. The fixed part M2 of the second piezoelectric vibrating membrane 22 is connected to the housing 1. For example, the fixed part M2 of the second piezoelectric vibrating membrane 22 is fixedly connected to the housing 1. The cantilever part N2 of the second piezoelectric vibrating membrane 22 is suspended and not connected to other structural components.

[0108] There is a gap 3 between the cantilever portion N1 of the first piezoelectric vibrating diaphragm 21 and the cantilever portion N2 of the second piezoelectric vibrating diaphragm 22. For example, the first end face P1 of the cantilever portion N1 of the first piezoelectric vibrating diaphragm 21, which is away from the fixed portion M1, is disposed opposite to the second end face P2 of the cantilever portion N2 of the second piezoelectric vibrating diaphragm 22, which is away from the fixed portion M2, and there is a gap 3 between the first end face P1 and the second end face P2. This gap 3 can be referred to as the diaphragm gap.

[0109] In this application example, the first end face P1 of the first piezoelectric vibrating membrane 21 is positioned opposite to the second end face P2 of the second piezoelectric vibrating membrane 22. This can be understood as follows: in some structures, the projection of the first end face P1 onto the second end face P2 partially overlaps with the second end face P2; in other structures, the projection of the first end face P1 onto the second end face P2 completely overlaps with the second end face P2; and in still other examples, the projection of the first end face P1 onto the second end face P2 may not overlap with the second end face P2, for example, as... Figure 4As shown, Figure 4 This is a cross-sectional view of another heat dissipation structure 800 in this application example, namely, the first piezoelectric vibrating film 21 and the second piezoelectric vibrating film 22 can be staggered by a certain distance in the Z direction.

[0110] The space inside the housing 1 located on one side of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 forms a first air duct 4, and the space inside the housing 1 located on the other side of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 forms a second air duct 5.

[0111] That is, the first piezoelectric vibrating diaphragm 21 has a first air duct 4 on one side and a second air duct 5 on the other side. The second piezoelectric vibrating diaphragm 22 has a first air duct 4 on one side and a second air duct 5 on the other side.

[0112] See Figure 3 The gap 3 connects the first air duct 4 and the second air duct 5, and the air inlet 101 and the air outlet 102 are connected through the first air duct 4 and the second air duct 5. In this way, the air inlet 101, the first air duct 4, the gap 3, the second air duct 5 and the air outlet 102 are connected.

[0113] exist Figure 3 In the example, gap 3 is positioned opposite to air outlet 102. This can be understood as follows: for example, air outlet 102 is located on the bottom plate of housing 1. In some examples, such as... Figure 4 The projection of gap 3 on the base plate partially overlaps with the air outlet 102; or, as Figure 3 In other examples, the projection of gap 3 onto the base plate completely overlaps with the air outlet 102.

[0114] The following was passed Figure 5 and Figure 6 The fluid motion principle of the heat dissipation structure exemplified in this application is introduced.

[0115] like Figure 5 When the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 both vibrate downwards, that is, vibrate in the direction of the second air duct 5, they can squeeze out the air in the second air duct 5, forming an upward vortex, and forming a jet that flows out from the air outlet 102. The vortex formed can draw the air in the air inlet 101 into the first air duct 4. The air drawn into the first air duct 4 can be ejected through the gap 3 and the air outlet 102.

[0116] For example, in Figure 5In the first air duct 4, the first piezoelectric vibrating diaphragm 21 vibrates downwards, which can form a counterclockwise vortex near the gap 3. The counterclockwise vortex can draw in more air at the air inlet 1011. The second piezoelectric vibrating diaphragm 22 vibrates downwards, which can form a clockwise vortex near the gap 3 in the first air duct 4. The clockwise vortex can draw in more air at the air inlet 1012.

[0117] like Figure 6 Both the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 vibrate upwards, that is, in the direction of the first air duct 4. This also creates upward-moving eddy currents. For example, when the first piezoelectric vibrating diaphragm 21 vibrates upwards, it can create counter-clockwise eddy currents near the gap 3 within the first air duct 4. These counter-clockwise eddy currents are more powerful than those described above. Figure 5 The counterclockwise eddy current shown is attenuated; the second piezoelectric vibrating diaphragm 22 vibrates upwards, which can form a clockwise eddy current near the gap 3 in the first air duct 4. The clockwise eddy current is more efficient than the one described above. Figure 5 The clockwise vortex flow shown diminishes, but it can still continuously draw air from the first air duct 4 into the gap 3. Furthermore, the drawn-in air can flow into the second air duct 5, where it is replenished to create positive pressure, which can then be used for the next... Figure 4 The jet is prepared when both the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 vibrate downwards.

[0118] Combination Figure 5 and Figure 6 By applying alternating current to the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 to make them vibrate up and down, air is introduced into the first air duct 4 from the air inlet 101, flows through the gap 3 between the piezoelectric vibrating diaphragms and finally flows out from the air outlet 102, forming air flow, exchanging heat with the heat source to remove heat. The jet at the air outlet can break the flow boundary layer, and the heat of the heating component can be quickly carried out through forced flow, achieving efficient active heat dissipation.

[0119] based on Figures 3 to 6 Based on the structure shown and the principle of fluid motion, it can be concluded that the heat dissipation structure of this application example is an active heat dissipation structure. It includes a first piezoelectric vibrating membrane 21 and a second piezoelectric vibrating membrane 22. One end of the first piezoelectric vibrating membrane 21 is fixed and the other end is suspended. One end of the second piezoelectric vibrating membrane 22 is fixed and the other end is suspended. That is, both piezoelectric vibrating membranes are cantilever beam membranes.

[0120] In some heat dissipation structures, a single piezoelectric vibrating diaphragm can be used, with the middle portion of the diaphragm fixed and only the ends vibrating. This application uses two piezoelectric vibrating diaphragms. Compared to a single piezoelectric vibrating diaphragm, with the area of ​​the diaphragm remaining unchanged, this application uses two cantilevered sections to vibrate, significantly increasing the amplitude of the piezoelectric vibrating diaphragm. This means that the effective working area of ​​the piezoelectric vibrating diaphragm is increased, and the fluid path is smooth, with small friction loss and local resistance loss, resulting in less airflow loss due to flow resistance. In this way, the airflow can be increased.

[0121] In addition, such as Figure 5 and Figure 6 Since the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 not only form an air inlet channel (first air channel) on one side, but also form an air gathering channel (second air channel) on the other side, and a gap is formed between the cantilevered parts of the two piezoelectric vibrating diaphragms, the combination of the air gathering channel, the gap and the air outlet can form a vortex, which can draw in more air from the air inlet and increase the air volume.

[0122] See Figure 5 and Figure 6 Since the gap 3 and the air outlet 102 are set opposite to each other in this application example, the air ejected from the gap 3 can be quickly ejected through the air outlet 102. The fluid flow path between the gap 3 and the air outlet 102 is short, which can reduce fluid loss. Therefore, under the same voltage drive, the air volume can be increased.

[0123] In some embodiments, such as Figure 3 As shown, the height h2 of the second air duct 5 is less than the height h1 of the first air duct 4.

[0124] The principle behind the generation of gas vortices is that when gas flows, it experiences resistance and inertia, causing it to rotate. When gas passes through a narrow channel, its flow velocity increases, forming vortices around the airflow. A vortex is a rotating airflow that, under certain conditions, exhibits a vortex-like structure. Figure 5 When the two piezoelectric diaphragms vibrate downwards (towards the second air duct 5), the height of the second air duct 5 is smaller, increasing its narrowness and the speed at which gas flows out. This creates a stronger vortex within the first air duct 4, which draws more air from the inlet into the first air duct 4, increasing airflow. Similarly, as... Figure 6 When the two piezoelectric vibrating diaphragms vibrate upwards (towards the first air duct 4), a vortex can also be formed in the first air duct 4. This vortex can draw in the air in the first air duct 4, and the drawn-in air can quickly replenish the air in the second air duct 5, preparing for the next downward movement of the piezoelectric vibrating diaphragm.

[0125] And, as Figure 5 and Figure 6 The two piezoelectric diaphragms vibrate downwards and upwards, and air is continuously ejected from the air outlet 102. In other words, the heat dissipation structure is a structure in which the fluid flows in one direction.

[0126] like Figure 7 As shown, Figure 7 The example is Figure 3 The flow field simulation diagram of the heat dissipation structure is shown. Figure 7 It includes multiple vibration modules. Figure 7 The darker the color, the greater the air velocity indicated; the lighter the color, the smaller the air velocity indicated. According to this flow field simulation diagram, when both the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 vibrate upwards, the air in the first air duct 4 enters the second air duct 5, forming air with a relatively high velocity above and below the gap.

[0127] like Figure 8 As shown, Figure 8 The example is Figure 3 The graph shows the integral curve of the airflow at the outlet of the heat dissipation structure over time. The horizontal axis represents time, and the vertical axis represents the cumulative value of the airflow at the outlet. The wind speed can be determined based on the slope of this integral curve. Figure 8 As can be seen, after 500µs, the airflow at the outlet steadily increases, such as... Figure 8 The slopes of points A and B are (5.2-3)*10. -8 / 【(1500-1000)*10 -6 =0.000472 / 0.000472 = 0.093 cubic feet per minute (cfm). Therefore, the airflow of the heat dissipation structure in this application is not only stable, but the wind speed can also reach 0.092 cubic feet per minute (cfm). Compared with the existing 0.05 cfm, the airflow is significantly improved, and the heat dissipation effect can be significantly optimized.

[0128] like Figure 9 As shown, Figure 9 The example is Figure 3 The airflow curve of the heat dissipation structure is shown. The horizontal axis represents time, and the vertical axis represents the airflow at the outlet. Based on this flow curve, it can be seen that the airflow at the outlet is positive after the 500µs stable period. Therefore, the airflow at the outlet is unidirectional and there is no backflow. In other words, when AC current is applied to the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 to make them vibrate up and down, the airflow path is maintained as follows: entering from the air inlet 101, flowing into the gap 3 through the air duct, and flowing out through the air outlet 102. There is basically no backflow or back suction phenomenon. In this way, the air volume can also be increased.

[0129] The first piezoelectric vibrating diaphragm 21 or the second piezoelectric vibrating diaphragm 22 can achieve various structures. For example, Figure 10 One of the possible structures is shown.

[0130] like Figure 10 The first piezoelectric vibrating film 21 or the second piezoelectric vibrating film 22 includes a semiconductor substrate 201, and a first electrode 202, a piezoelectric layer 203 and a second electrode 204 disposed on the semiconductor substrate 201, wherein the piezoelectric layer 203 is located between the first electrode 202 and the second electrode 204.

[0131] When voltages are applied to the first electrode 202 and the second electrode 204 respectively, electrical energy is converted into mechanical energy of the cantilever movement through the piezoelectric effect. The mechanical energy of the cantilever movement drives the air to form a unidirectional flow, and heat is transferred away by exchanging heat with the heat source.

[0132] In some feasible processes, the first piezoelectric vibrating membrane 21 or the second piezoelectric vibrating membrane 22 can be fabricated using micro-electro-mechanical system (MEMS) technology.

[0133] For example, such as Figures 11 to 14 As shown, Figures 11 to 14 A method for preparing a first piezoelectric vibrating membrane 21 or a second piezoelectric vibrating membrane 22 is shown.

[0134] exist Figure 11 In this process, a semiconductor wafer is obtained. This semiconductor wafer can be a silicon wafer, such as silicon-on-insulator (SOI). SOI consists of a bottom silicon layer and a top silicon layer, as well as an oxide layer stacked between the bottom silicon layer and the top silicon layer.

[0135] In other examples, the semiconductor wafer may be at least one of a germanium substrate, a germanium-silicon substrate, a gallium nitride substrate, or an indium gallium arsenide substrate.

[0136] exist Figure 12In this process, a first electrode 202, a piezoelectric layer 203, and a second electrode 204 are formed on a semiconductor wafer. The first electrode 202, the piezoelectric layer 203, and the second electrode 204 can be fabricated using epitaxial growth processes, such as metal-organic chemical vapor deposition (MOCVD), molecular beam epitaxy (MBE), physical vapor deposition (PVD), low-pressure chemical vapor deposition (LPCVD), plasma-enhanced chemical vapor deposition (PECVD), or atomic layer deposition (ALD).

[0137] exist Figure 13 In the process, the first electrode 202, the piezoelectric layer 203 and the second electrode 204 stacked on the semiconductor wafer are etched to obtain the piezoelectric unit.

[0138] exist Figure 14 In this process, etching processes can be used to etch semiconductor wafers, such as... Figure 14 In this process, the region of the semiconductor wafer where the piezoelectric unit is located is thinned to form a first part R1, and the thicker region forms a second part R2. The second part R2 can serve as a fixed part of the piezoelectric vibrating film, and the first part R1 can support the first electrode 202, the piezoelectric layer 203 and the second electrode 204 in the above example, serving as a cantilever part.

[0139] This application does not impose any special limitation on the location of the first electrode 202, the piezoelectric layer 203, and the second electrode 204. For example, they can be located in the middle region of the first part R1, or they can be located near the end of the first part R1.

[0140] use Figures 11 to 14 The first piezoelectric vibrating film 21 or the second piezoelectric vibrating film 22 fabricated in the example shown have a semiconductor substrate for the fixed portion and a semiconductor substrate for the cantilever portion that are integrally formed. The thickness of the semiconductor substrate for the fixed portion of the piezoelectric vibrating film is greater than the thickness of the semiconductor substrate for the cantilever portion.

[0141] like Figure 15In some heat dissipation structures, the semiconductor substrate 201 of the fixed portion can be fixedly connected to the housing 1 through the adhesive layer 6. For example, the fixed portion M1 of the first piezoelectric vibrating film 21 is fixedly connected to the housing 1 through the adhesive layer 6, and the fixed portion M2 of the second piezoelectric vibrating film 22 is fixedly connected to the housing 1 through the adhesive layer 6.

[0142] In some examples, such as Figure 15 The first electrode 202, the piezoelectric layer 203, and the second electrode 204 can be disposed on the side of the semiconductor substrate 201 facing the first air duct 4; in other examples, the first electrode 202, the piezoelectric layer 203, and the second electrode 204 can be disposed on the side of the semiconductor substrate 201 facing the second air duct 5.

[0143] In some structures, the combined thickness of the first electrode 202, the piezoelectric layer 203, and the second electrode 204 can be from 1 μm to 10 μm.

[0144] This application uses micro-electro-mechanical system (MEMS) technology to process and fabricate a first piezoelectric vibrating membrane 21 or a second piezoelectric vibrating membrane 22. The thickness of the piezoelectric vibrating membrane can be on the order of several μm to tens of μm, the length can be on the order of hundreds of μm to thousands of μm, and the resonant frequency of the cantilever portion of the piezoelectric vibrating membrane can be on the order of tens of kHz to hundreds of kHz.

[0145] For example, the thickness (dimension along the Z direction) of a vibration module can be approximately 1 mm, the length (dimension along the Y direction) can be 2–3 mm, and the floor space can be approximately 10 mm². 2 In summary, this heat dissipation structure can be miniaturized using MEMS.

[0146] In some feasible processes, the following methods are employed: Figures 11 to 14 The method can produce a heat dissipation structure with a length of 9.5 mm, a width of 8 mm, and a thickness of 0.6 mm to 1 mm. Through piezoelectric-solid mechanics-fluid-structure interaction quantitative simulation, the heat dissipation structure (size 9.5*8 mm, thickness 0.6~1 mm) can achieve an air volume of about 0.092 cfm.

[0147] In some structures, the width (dimension along the Y direction) of the gap 3 between the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 can be from tens of μm to about 200 μm, and the height h2 of the second air duct 5 can be from tens of μm to 100 μm; the characteristic frequency of the first mode of vibration of the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 can be from tens of kHz to hundreds of kHz, which belongs to the ultrasonic frequency band that is inaudible to the human ear, thus reducing noise in the audible band.

[0148] The frequency of the driving current is equal to the resonant frequency of the cantilever section to form resonance. For example, the amplitude of the cantilever section can be on the order of tens of μm and appropriately smaller than the height of the second air duct (air concentrator) to prevent impact during vibration.

[0149] In the heat dissipation structure of this application example, the airflow path is relatively short. For example, after the air in the inlet duct (first air duct) passes through the gap between the two cantilever sections, because the gap is positioned opposite the outlet, the air can quickly pass through the outlet and be ejected, resulting in minimal fluid loss, reduced power consumption, and improved energy efficiency. For example, as... Figure 16 As shown, Figure 16 The example is Figure 3 The power consumption curve of the heat dissipation structure shown is illustrated, with the horizontal axis representing time and the vertical axis representing power. Figure 16 The average power can be calculated to be 0.088W. The ratio of airflow to average power is the energy efficiency, and the energy efficiency of this application is 0.092cfm / 0.088W = 1.05cfm / W. Compared with the energy efficiency of existing heat dissipation structures (0.2cfm / W), this can effectively improve the energy efficiency of the heat dissipation structure.

[0150] Therefore, the heat dissipation structure of this application example is not only small in size and can be adapted to small electronic devices, but also enables the air to flow in one direction in general, and can reduce fluid loss, increase air volume, reduce power consumption and improve energy efficiency.

[0151] In some feasible embodiments, such as Figure 17 The housing 1 may include a top cover 11, a side plate 12 and a bottom plate 13, which are connected to form a housing 1 with an internal cavity.

[0152] The top cover 11 can be made of at least one material, including metal and plastic. The side panel 12 can be made of at least one material, including metal and plastic. The bottom panel 13 can be made of at least one material, including metal and plastic. The materials of the top cover 11, side panel 12, and bottom panel 13 can be the same or different.

[0153] The top cover 11, side plate 12, and bottom plate 13 can be a single integrated structure. Alternatively, they can be connected by a connecting structure, such as a welded structure or a threaded connection structure.

[0154] Since the first piezoelectric diaphragm 21 and the second piezoelectric diaphragm 22 need to be electrically connected to the driver, an alternating current is applied to the first piezoelectric diaphragm 21 and the second piezoelectric diaphragm 22 by the driver. To simplify the wiring... Figure 17At least one of the top cover 11, side plate 12 or bottom plate 13 is a circuit board, the first piezoelectric diaphragm 21 and the second piezoelectric diaphragm 22 are connected to the circuit board, and the circuit board is then electrically connected to the driver.

[0155] In some embodiments, such as Figure 17 The base plate 13 can be a circuit board, for example, a printed circuit board (PCB). The circuit board has a circuit layer 131, so that the electrodes in the piezoelectric vibrating diaphragm can be electrically connected to the circuit board, and the circuit board can then be electrically connected to other driving circuits through an electrical connection structure.

[0156] For example, such as Figure 17 The first and second electrodes in the piezoelectric vibrating membrane can be electrically connected to the circuit board via lead 7. For example, lead 7 can be fabricated using wire bonding technology.

[0157] When the base plate 132 of the housing 1 is a circuit board, an air outlet 102 can be opened on the circuit board.

[0158] In some implementations, such as Figure 18 He Ru Figure 19 , Figure 18 The diagram shows the structure of the gap 3 formed by the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22. Figure 19 This is a top view of a circuit board 13 as an example of this application.

[0159] like Figure 19 A slot can be formed in the circuit board 13, which serves as an air outlet 102. For example, the circuit board 13 has opposing first and second sides, and the arrangement direction of the first and second sides is consistent with the extension direction of the gap 3. The air outlet 102 passes through the first and second sides. Figure 19 If the gap 3 between the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 extends along the X direction, then... Figure 19 The groove extends along the X direction and can penetrate the first and second sides.

[0160] In some other implementations, such as Figure 20 , Figure 20 This is a top view of another circuit board 13 in this application example. Multiple holes can be formed on the circuit board 13, serving as air outlets 102. For example, the circuit board 13 has opposing first and second sides, the arrangement direction of the first and second sides being consistent with the extending direction of the gap 3. Multiple holes are spaced apart between the first and second sides. The gap 3 between the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 extends along the X direction. Figure 20 Multiple holes are arranged at intervals along the X direction.

[0161] Because the circuit board has a circuit layer 131, it adopts... Figure 20 When the multiple holes arranged at intervals are used as air outlets 102, the multiple holes can bypass the wiring layer 131, thus avoiding damage to the wiring layer 131.

[0162] Figure 20 The shape of the hole shown can be rectangular, circular, elliptical, or an irregular shape.

[0163] Figure 20 The multiple holes shown may be the same size or different in shape.

[0164] use Figure 19 When the groove shown is used as the air outlet 102, the projection of the gap 3 between the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 onto the circuit board 13 can be as follows: Figure 19 The dashed box shown indicates that the orthographic projection of gap 3 can be located within or near the boundary of air outlet 102.

[0165] use Figure 20 When the multiple holes shown serve as air outlets 102, the projection of the gap 3 between the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 onto the circuit board 13 can be as follows: Figure 20 The dashed box shown indicates that the orthographic projection of gap 3 can be located within the boundary of the area enclosed by multiple air outlets 102, or close to the boundary of air outlet 102.

[0166] In the heat dissipation structure provided in this application, the location of the air inlet can be varied, and several implementation structures are given as examples below.

[0167] like Figure 21 , Figure 21 This demonstrates one arrangement of the air inlets. This example includes multiple air inlets, such as a first air inlet 1011 and a second air inlet 1012, both of which are located on the top cover 11. The first air inlet 1011 and the second air inlet 1012 can be located on opposite sides of the gap 3.

[0168] like Figure 22 , Figure 22 Another arrangement of the air inlet is shown. In this example, a first air inlet 1011 is provided on the top cover 11. The first air inlet 1011 is located on one side of the gap 3. The gap 3 can be arranged without being opposite to the first air inlet 1011. That is, the first air inlet 1011 and the gap 3 are staggered along the arrangement direction of the first piezoelectric vibrating membrane and the second piezoelectric vibrating membrane.

[0169] like Figure 23 , Figure 23 This demonstrates another configuration of the air inlet. In this example, a first air inlet 1011 is provided on the top cover 11 and is positioned opposite to the gap 3.

[0170] The first air inlet 1011 is positioned opposite to the gap 3. This can be understood as the projection of the gap 3 onto the top cover 11 partially overlapping with the first air inlet 1011; or, in other examples, the projection of the gap 3 onto the top cover 11 completely overlaps with the first air inlet 1011.

[0171] like Figure 24 , Figure 24 This demonstrates another configuration of the air inlet. In this example, a first air inlet 1011 is provided on the side panel 12.

[0172] like Figure 25 , Figure 25 This demonstrates another arrangement of the air inlet. In this example, there is a first air inlet 1011 and a second air inlet 1012. Both the first air inlet 1011 and the second air inlet 1012 are located on the side plate 12. The first air inlet 1011 and the second air inlet 1012 can be arranged opposite each other on both sides of the gap 3.

[0173] The heat dissipation structure provided in the embodiments of this application, such as Figure 26 As shown, the heating element can be placed at the air inlet 101, and the heat emitted by the heating element is dissipated through the heat dissipation structure. Alternatively, the heating element can be placed at the air outlet 102, where the air exchanges heat with the heating element after leaving the heat dissipation structure.

[0174] In the heat dissipation structures shown above, the fixed portion M1 of the first piezoelectric diaphragm 21 is connected to the base plate 13 of the housing 1, and the fixed portion M1 of the second piezoelectric diaphragm 22 is also connected to the base plate 13 of the housing 1. In other examples, such as... Figure 27 As shown, the fixing portion M1 of the first piezoelectric vibrating diaphragm 21 is connected to the top cover 11 of the housing 1, and the fixing portion M1 of the second piezoelectric vibrating diaphragm 22 is connected to the top cover 11 of the housing 1. In some other examples, the fixing portion M1 of the first piezoelectric vibrating diaphragm 21 is connected to the side plate 12 of the housing 1, and the fixing portion M1 of the second piezoelectric vibrating diaphragm 22 is connected to the side plate 12 of the housing 1.

[0175] In this application example, the first piezoelectric vibrating diaphragm 21 and the second piezoelectric vibrating diaphragm 22 have multiple vibration modes.

[0176] For example, as above Figure 5 and Figure 6As shown, at the same time, the vibration direction of the first piezoelectric vibrating membrane 21 is the same as that of the second piezoelectric vibrating membrane 22. For example, when the first piezoelectric vibrating membrane 21 vibrates upward, the second piezoelectric vibrating membrane 22 also vibrates upward; or, when the first piezoelectric vibrating membrane 21 vibrates downward, the second piezoelectric vibrating membrane 22 also vibrates downward.

[0177] When the vibration directions of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 are the same, the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 can vibrate in phase, or they can have a phase difference.

[0178] For example, such as Figure 28 As shown, at the same time, the vibration direction of the first piezoelectric vibrating membrane 21 is different from that of the second piezoelectric vibrating membrane 22. For example, when the first piezoelectric vibrating membrane 21 vibrates upward, the second piezoelectric vibrating membrane 22 vibrates downward; or, when the first piezoelectric vibrating membrane 21 vibrates downward, the second piezoelectric vibrating membrane 22 vibrates upward.

[0179] When the vibration directions of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 are not the same, the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 can vibrate out of phase, or they can have a phase difference.

[0180] In some heat dissipation structures, such as the example above, a vibration module can be installed; in other heat dissipation structures, such as... Figure 29 As shown, multiple vibration modules can be arranged within the housing. For example, it can include a first vibration module and a second vibration module. The first and second vibration modules can be arranged along the length of the housing. Figure 29 In the middle, the first vibration module and the second vibration diaphragm group are arranged along the Y direction.

[0181] In other examples, more vibration modules can be deployed along one direction, such as three, four, or more.

[0182] like Figure 29 As shown, the second piezoelectric vibrating membrane 221 in the first vibration module and the first piezoelectric vibrating membrane 212 in the second vibration module are adjacent. In some embodiments, the second piezoelectric vibrating membrane 221 in the first vibration module and the first piezoelectric vibrating membrane 212 in the second vibration module can be connected.

[0183] In other examples, when the housing is of other shapes, such as circular or elliptical, or other irregular shapes, the cantilever portion of the second piezoelectric vibrating membrane 221 and the cantilever portion of the first piezoelectric vibrating membrane 212 extend in opposite directions, that is, the cantilever portion of the second piezoelectric vibrating membrane 221 and the cantilever portion of the first piezoelectric vibrating membrane 212 are arranged back to back.

[0184] In some examples, the second piezoelectric diaphragm 221 and the first piezoelectric diaphragm 212 can be fabricated using microelectromechanical systems (MEMS).

[0185] like Figures 30 to 32 The fabrication of the second piezoelectric vibrating membrane 221 and the first piezoelectric vibrating membrane 212 is shown.

[0186] exist Figure 30 In this process, a semiconductor wafer is obtained. This semiconductor wafer can be a silicon wafer, such as silicon-on-insulator (SOI).

[0187] A first electrode 202, a piezoelectric layer 203, and a second electrode 204 are formed on a semiconductor wafer. The first electrode 202, the piezoelectric layer 203, and the second electrode 204 can be fabricated using an epitaxial growth process.

[0188] exist Figure 31 In the process, the first electrode 202, the piezoelectric layer 203 and the second electrode 204 stacked on the semiconductor wafer are etched to obtain two piezoelectric units.

[0189] exist Figure 32 In this process, etching processes can be used to etch semiconductor wafers, such as... Figure 32 In this process, two regions of the semiconductor wafer are thinned. The thicker region forms the fixed part of the piezoelectric vibrating film, and the thinner region forms the cantilever part of the piezoelectric vibrating film.

[0190] like Figure 32 The semiconductor substrate 201 of the second piezoelectric vibrating film 221 and the semiconductor substrate 201 of the first piezoelectric vibrating film 212 are integrally structured.

[0191] In some heat dissipation structures, multiple vibration modules housed within the housing can be arranged along the width of the housing. For example, multiple vibration modules can also be arranged along the X direction, which is perpendicular to the Y direction.

[0192] like Figure 33 An example is shown where 5 vibration modules are arranged in the Y direction of the shell length and 2 vibration modules are arranged in the X direction of the shell width, thereby forming a 5x2 vibration module array.

[0193] like Figure 34 As shown, Figure 34 An exemplary structural diagram of multiple vibration modules arranged along the X-direction of the shell width is shown. In this example, a third vibration module and a fourth vibration module are arranged along the shell width direction. The first piezoelectric vibration membrane 211 of the third vibration module and the first piezoelectric vibration membrane 213 of the fourth vibration membrane group are arranged along the shell width direction, and the second piezoelectric vibration membrane 221 of the third vibration module and the second piezoelectric vibration membrane 223 of the fourth vibration membrane group are arranged along the shell width direction.

[0194] In other examples, when the shell is of other shapes, such as circular, elliptical, or other irregular shapes, the extension direction of the cantilever portion of the first piezoelectric vibrating diaphragm 211 of the third vibration module is the same as the extension direction of the cantilever portion of the first piezoelectric vibrating diaphragm 213 of the fourth vibration diaphragm group, that is, they extend in the same direction; the extension direction of the cantilever portion of the second piezoelectric vibrating diaphragm 221 of the third vibration module is the same as the extension direction of the cantilever portion of the second piezoelectric vibrating diaphragm 223 of the fourth vibration diaphragm group, that is, they extend in the same direction.

[0195] To avoid interference between the vibrations of the first piezoelectric vibrating diaphragm 211 of the third vibration module and the first piezoelectric vibrating diaphragm 213 of the fourth vibration diaphragm group, such as Figure 34 There is a gap between the first piezoelectric vibrating membrane 211 of the third vibration module and the first piezoelectric vibrating membrane 213 of the fourth vibration membrane group.

[0196] To avoid interference between the vibrations of the second piezoelectric vibrating diaphragm 221 of the third vibration module and the second piezoelectric vibrating diaphragm 223 of the fourth vibration diaphragm group, such as Figure 34 There is a gap between the second piezoelectric vibrating membrane 221 of the third vibration module and the second piezoelectric vibrating membrane 223 of the fourth vibration membrane group.

[0197] In some examples, among multiple vibration modules arranged along the length or width of the housing, the vibration directions of the piezoelectric diaphragms in different vibration modules may be the same or different.

[0198] For example, in Figure 29 In the first moment, in the first vibration module, the vibration direction of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 is both upward; in the second vibration membrane group, the vibration direction of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 is both downward; or, in the second vibration membrane group, the vibration direction of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 is both upward.

[0199] For example, in the first vibration module, the vibration direction of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 is both upward, and in the second vibration membrane group, when the vibration direction of the first piezoelectric vibrating membrane 21 and the second piezoelectric vibrating membrane 22 is both upward, the vibration of the two sets of piezoelectric vibrating membranes can have a phase difference.

[0200] For example, in Figure 34 In the first moment, in the third vibration module, the vibration direction of the first piezoelectric vibrating membrane 211 and the second piezoelectric vibrating membrane 221 is both upward. In the fourth vibration membrane group, the vibration direction of the first piezoelectric vibrating membrane 213 and the second piezoelectric vibrating membrane 223 is both downward. Alternatively, in the fourth vibration membrane group, the vibration direction of the first piezoelectric vibrating membrane 213 and the second piezoelectric vibrating membrane 223 is both upward.

[0201] like Figure 35 , Figure 35 This is a partial structural diagram of a heat dissipation structure provided in an embodiment of this application. In this example, the air inlet 101 is formed on the top cover 11, and the extending direction of the air inlet 101 is parallel to the extending direction of the gap. The air inlet 101 may be opposite to the gap.

[0202] By placing the air inlet 101 on the top cover 11, more air inlets can be opened as needed to increase air volume.

[0203] In some configurations, the size of the air outlet 102 and the gap 3 can be adjusted to control the air outlet speed and air volume.

[0204] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0205] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A heat dissipation structure, characterized in that, include: A housing having an air inlet and an air outlet; At least one vibration module is disposed within the housing; Each of the vibration modules includes a first piezoelectric vibrating diaphragm and a second piezoelectric vibrating diaphragm; Both the first piezoelectric vibrating membrane and the second piezoelectric vibrating membrane include a fixed portion and a cantilever portion; Both the fixed portion of the first piezoelectric vibrating membrane and the fixed portion of the second piezoelectric vibrating membrane are connected to the housing. Both the cantilever portion of the first piezoelectric vibrating membrane and the cantilever portion of the second piezoelectric vibrating membrane are suspended in the air. The surface of the cantilever portion of the first piezoelectric vibrating membrane away from the fixed portion is the first end face, and the surface of the cantilever portion of the second piezoelectric vibrating membrane away from the fixed portion is the second end face. The first end face and the second end face are arranged opposite to each other and there is a gap between them. The space inside the housing located on one side of the first piezoelectric vibrating membrane and the second piezoelectric vibrating membrane forms a first air duct, and the space inside the housing located on the other side of the first piezoelectric vibrating membrane and the second piezoelectric vibrating membrane forms a second air duct. The gap connects the first air duct and the second air duct. The air inlet and the air outlet are connected through the first air duct and the second air duct, and the gap is set opposite to the air outlet.

2. The heat dissipation structure according to claim 1, characterized in that, The height of the second air duct is less than the height of the first air duct.

3. The heat dissipation structure according to claim 1 or 2, characterized in that, At least one of the first piezoelectric vibrating membrane or the second piezoelectric vibrating membrane includes: Semiconductor substrate; A first electrode, a piezoelectric layer, and a second electrode are disposed on the semiconductor substrate, wherein the piezoelectric layer is located between the first electrode and the second electrode.

4. The heat dissipation structure according to claim 3, characterized in that, The semiconductor substrate of the fixed portion and the semiconductor substrate of the cantilever portion are an integral structure.

5. The heat dissipation structure according to claim 3 or 4, characterized in that, The thickness of the semiconductor substrate in the fixed portion is greater than the thickness of the semiconductor substrate in the cantilever portion, and the fixed portion is connected to the housing via an adhesive layer.

6. The heat dissipation structure according to any one of claims 3-5, characterized in that, The semiconductor substrate includes at least one of the following: silicon substrate, germanium substrate, germanium-silicon substrate, gallium nitride substrate, or indium gallium arsenide substrate.

7. The heat dissipation structure according to any one of claims 3-6, characterized in that, The first electrode, the piezoelectric layer, and the second electrode are disposed on the side of the cantilever portion facing the first air duct.

8. The heat dissipation structure according to any one of claims 1-7, characterized in that, The housing includes a top cover, side plates, and a bottom plate, which are connected to form a cavity for accommodating the at least one vibration module; At least one of the top cover, the side plate, or the bottom plate is a circuit board; The first and second piezoelectric vibrating membranes are electrically connected to the circuit board.

9. The heat dissipation structure according to claim 8, characterized in that, The base plate is a circuit board, and the air outlet is located on the circuit board.

10. The heat dissipation structure according to claim 9, characterized in that, The air outlet includes multiple outlets, which are arranged at intervals along a direction parallel to the direction of the gap extension.

11. The heat dissipation structure according to any one of claims 8-10, characterized in that, The air inlet is provided on the top cover.

12. The heat dissipation structure according to claim 11, characterized in that, The air inlet and the gap are arranged opposite to each other; or, the air inlet and the gap are staggered along the arrangement direction of the first piezoelectric vibrating membrane and the second piezoelectric vibrating membrane.

13. The heat dissipation structure according to any one of claims 8-12, characterized in that, The air inlet is provided on the side panel.

14. The heat dissipation structure according to claim 1 or 2, characterized in that, The at least one vibration module includes an adjacent first vibration module and a second vibration module, the first vibration module and the second vibration module being arranged along the length direction of the housing; The first piezoelectric diaphragm of the second vibration module and the second piezoelectric diaphragm of the first vibration module each include: Semiconductor substrate; A first electrode, a piezoelectric layer, and a second electrode are disposed on the semiconductor substrate, wherein the piezoelectric layer is located between the first electrode and the second electrode; The semiconductor substrate of the first piezoelectric vibration film of the second vibration module is an integral structure with the semiconductor substrate of the second piezoelectric vibration film of the first vibration module.

15. The heat dissipation structure according to any one of claims 1, 2, or 14, characterized in that, The at least one vibration module includes an adjacent third vibration module and a fourth vibration module, the third vibration module and the fourth vibration module being arranged along the width direction of the housing; The first piezoelectric vibration membrane of the third vibration module and the first piezoelectric vibration membrane of the fourth vibration module both include: Semiconductor substrate; A first electrode, a piezoelectric layer, and a second electrode are disposed on the semiconductor substrate, wherein the piezoelectric layer is located between the first electrode and the second electrode; The semiconductor substrate of the first piezoelectric vibration film of the third vibration module has a gap with the semiconductor substrate of the first piezoelectric vibration film of the fourth vibration module.

16. The heat dissipation structure according to claim 1 or 2, characterized in that, The at least one vibration module includes an adjacent first vibration module and a second vibration module; The cantilever portion of the first piezoelectric vibrating membrane of the second vibration module extends in the opposite direction to the cantilever portion of the second piezoelectric vibrating membrane of the first vibration module. The first piezoelectric diaphragm of the second vibration module and the second piezoelectric diaphragm of the first vibration module each include: Semiconductor substrate; A first electrode, a piezoelectric layer, and a second electrode are disposed on the semiconductor substrate, wherein the piezoelectric layer is located between the first electrode and the second electrode; The semiconductor substrate of the first piezoelectric vibration film of the second vibration module is an integral structure with the semiconductor substrate of the second piezoelectric vibration film of the first vibration module.

17. The heat dissipation structure according to any one of claims 1, 2, or 16, characterized in that, The at least one vibration module includes an adjacent third vibration module and a fourth vibration module; The cantilever portion of the first piezoelectric vibrating membrane of the third vibration module extends in the same direction as the cantilever portion of the first piezoelectric vibrating membrane of the fourth vibration module. The first piezoelectric vibration membrane of the third vibration module and the first piezoelectric vibration membrane of the fourth vibration module both include: Semiconductor substrate; A first electrode, a piezoelectric layer, and a second electrode are disposed on the semiconductor substrate, wherein the piezoelectric layer is located between the first electrode and the second electrode; The semiconductor substrate of the first piezoelectric vibration film of the third vibration module has a gap with the semiconductor substrate of the first piezoelectric vibration film of the fourth vibration module.

18. An electronic device, characterized in that, include: Heating components; The heat dissipation structure according to any one of claims 1-17 is used to dissipate heat from the heat-generating component.

19. The electronic device according to claim 18, characterized in that, The heating element is located at the air inlet of the heat dissipation structure, or the heating element is located at the air outlet of the heat dissipation structure.

20. The electronic device according to claim 18 or 19, characterized in that, The electronic device further includes a driver, wherein the first piezoelectric vibrating diaphragm and the second piezoelectric vibrating diaphragm are connected to the driver, and the driver is used to drive the first piezoelectric vibrating diaphragm and the second piezoelectric vibrating diaphragm to vibrate in the same direction.

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