Heat dissipation device and electronic equipment

Abstract

The invention provides a heat dissipation device and electronic equipment, and relates to the technical field of circuits, and the heat dissipation device comprises a heat conduction layer which covers a heat dissipation target; the heat dissipation layer is located on the side, away from the heat dissipation target, of the heat conduction layer; the packaging layer is located on the side, away from the heat dissipation target, of the heat dissipation layer; wherein the heat dissipation layer comprises a plurality of cavity walls and a plurality of cantilever structures, the plurality of cavity walls are arranged side by side and supported between the heat conduction layer and the packaging layer, the plurality of cantilever structures are distributed on the plurality of cavity walls, the cantilever structures comprise piezoelectric materials, and the piezoelectric materials vibrate based on an alternating current electric field. Based on the scheme, the heat dissipation device can have higher heat dissipation capability.

Description

Technical Field

[0001] The present application relates to the field of circuit technology, and more specifically, to a heat dissipation device and an electronic device. Background Art

[0002] As the power of electronic components continues to increase, the performance of electronic devices has been greatly improved, but this has also led to the heat dissipation problem of electronic devices becoming more prominent. If the heat dissipation is not good, the temperature of the electronic device will be too high, affecting the stability and reliability of the electronic device operation, and may even burn the circuit board. In this regard, heat dissipation devices can be introduced into electronic devices, but these heat dissipation devices have problems such as low heat dissipation efficiency, large space occupation, and high operating noise. Summary of the invention

[0003] The present application provides a heat dissipation device and an electronic device, wherein the heat dissipation device has a stronger heat dissipation capacity, occupies a smaller space, and has a smaller operating noise.

[0004] In a first aspect, a heat dissipation device is provided, comprising: a thermally conductive layer, which covers a heat dissipation target; a heat dissipation layer, which is located on a side of the thermally conductive layer away from the heat dissipation target; and a packaging layer, which is located on a side of the heat dissipation layer away from the heat dissipation target; wherein the heat dissipation layer comprises a plurality of chamber walls and a plurality of cantilever structures, the plurality of chamber walls are arranged side by side and supported between the thermally conductive layer and the packaging layer, the plurality of cantilever structures are distributed on the plurality of chamber walls, and the cantilever structures comprise a piezoelectric material, and the piezoelectric material vibrates based on an alternating electric field.

[0005] In combination with the first aspect, in some implementations of the first aspect, the cantilever structure includes: a cantilever body and a first piezoelectric material layer, and the first piezoelectric material layer covers at least a portion of the first side surface of the cantilever body.

[0006] In combination with the first aspect, in certain implementations of the first aspect, the cantilever structure further includes a counterweight portion, and the counterweight portion is located at the free end of the cantilever body.

[0007] In combination with the first aspect, in certain implementations of the first aspect, the cantilever structure also includes: a first grounding electrode, which is located on a side of the first piezoelectric material layer away from the cantilever body; and a first driving electrode, which is located between the first piezoelectric material layer and the cantilever body.

[0008] In combination with the first aspect, in some implementations of the first aspect, the heat dissipation device further includes: an AC power supply, which is electrically connected to the first driving electrode.

[0009] In combination with the first aspect, in some implementations of the first aspect, an operating frequency of the AC power supply is greater than or equal to 20 kHz.

[0010] In combination with the first aspect, in some implementations of the first aspect, the cantilever structure further includes a second piezoelectric material layer, and the second piezoelectric material layer covers at least a portion of the second side surface of the cantilever body.

[0011] In combination with the first aspect, in certain implementations of the first aspect, the cantilever structure also includes: a second grounding electrode, the second grounding electrode is located on the side of the second piezoelectric material layer away from the cantilever body; a second driving electrode, the second driving electrode is located between the second piezoelectric material layer and the cantilever body, and the second driving electrode is electrically connected to the AC power supply.

[0012] In combination with the first aspect, in certain implementations of the first aspect, two adjacent chamber walls form an air channel, and the air channel includes a first opening and a second opening, and a caliber of the first opening is greater than or equal to a caliber of the second opening.

[0013] In combination with the first aspect, in some implementations of the first aspect, the heat conducting layer includes a plurality of first grooves, and / or the packaging layer includes a plurality of second grooves.

[0014] In combination with the first aspect, in some implementations of the first aspect, the cantilever structure includes a piezoelectric micromachined ultrasonic transducer (PMUT) or a capacitive micromachined ultrasonic transducer (CMUT).

[0015] In combination with the first aspect, in certain implementations of the first aspect, the distance between the multiple cantilever structures is greater than or equal to a distance threshold.

[0016] In combination with the first aspect, in some implementations of the first aspect, the thickness of the thermal conductive layer, the heat dissipation layer, and the packaging layer is below a millimeter level.

[0017] In a second aspect, an electronic device is provided, including a heat dissipation target and a heat dissipation device in any possible implementation of the heat dissipation device design of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a design scheme of a heat sink 110 proposed at this stage;

[0019] Figure 2 is a structural schematic diagram of a heat dissipation device 200 proposed in an embodiment of the present application;

[0020] Figure 3 is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application;

[0021] Figure 4 is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application;

[0022] Figure 5 is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application;

[0023] Figure 6 is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application;

[0024] Figure 7 is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application;

[0025] Figure 8 is a structural schematic diagram of a cantilever structure 222 proposed in an embodiment of the present application;

[0026] Fig. 9 is a structural schematic diagram of another cantilever structure 222 proposed in an embodiment of the present application;

[0027] Fig.10 is a structural schematic diagram of another cantilever structure 222 proposed in an embodiment of the present application;

[0028] Fig.11 It is a flow chart of a method 1100 for preparing a heat dissipation device proposed in an embodiment of the present application. DETAILED DESCRIPTION

[0029] The technical solution in this application will be described below in conjunction with the accompanying drawings.

[0030] The embodiments of the present application will present various aspects, embodiments or features around a system including multiple devices, components, modules, etc. It should be understood and appreciated that each system may include additional devices, components, modules, etc., and / or may not include all devices, components, modules, etc. discussed in conjunction with the figures. In addition, combinations of these schemes may also be used.

[0031] In addition, in the embodiments of the present application, words such as "exemplary" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present concepts in a concrete way.

[0032] The business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. Ordinary technicians in this field can know that with the evolution of technology and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

[0033] References to "one embodiment" or "some embodiments" etc. described in this specification mean that a particular feature, structure or characteristic described in conjunction with the embodiment is included in one or more embodiments of the present application. Thus, the phrases "in one embodiment", "in some embodiments", "in some other embodiments", "in some other embodiments", etc. that appear at different places in this specification do not necessarily refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in other ways. The terms "including", "comprising", "having" and their variations all mean "including but not limited to", unless otherwise specifically emphasized in other ways.

[0034] In the embodiments of the present application, "at least one" refers to one or more, and "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can be represented by: including the existence of A alone, the existence of A and B at the same time, and the existence of B alone, where A and B can be singular or plural. The character " / " generally indicates that the previous and subsequent associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0035] In the description of the embodiments of the present application, the directions or positional relationships indicated by terms such as "up", "down", "left", "right", "inside", "outside", "vertical" and "horizontal" are defined relative to the directions or positions of the components schematically placed in the drawings. It should be understood that these directional terms are relative concepts. They are used for relative description and clarification, rather than indicating or implying that the device or component referred to must have a specific direction, or be constructed and operated in a specific direction. They may change accordingly according to changes in the directions of the components placed in the drawings, and therefore cannot be understood as limitations on the present application.

[0036] In the embodiments of the present application, the same reference numerals are used to represent the same components or parts. For the same parts in the embodiments of the present application, only one of the parts or parts may be marked with a reference numeral in the figure. It should be understood that the reference numerals are also applicable to other identical parts or parts. In addition, the various parts in the drawings are not drawn to scale, and the sizes and dimensions of the parts shown in the drawings are only exemplary and should not be understood as limiting the present application.

[0037] As the power of electronic components continues to increase, the performance of electronic equipment has been greatly improved, but this has also led to the heat dissipation problem of electronic equipment becoming more prominent. When electronic equipment is running, excessively high temperatures will affect the performance of electronic components, such as reducing the life of capacitors and resistors, degrading the performance of transformers and insulation materials, and causing transistor failure. In addition, excessively high temperatures can also cause damage to electronic equipment, thermal aging of materials, cracking of low-melting-point welds, solder joint detachment, reduced mechanical strength, and other problems, which directly affect product quality. It can be seen that heat dissipation operations for electronic equipment are of great significance to ensuring the stable operation of electronic equipment, extending the service life of equipment, and improving product quality.

[0038] In this regard, a solution of dissipating heat for electronic devices through heat dissipation devices has been proposed in the art to address the problem of excessively high operating temperatures of electronic devices.

[0039] Figure 1 This is a design scheme of the heat dissipation device 110 proposed at this stage.

[0040] refer to Figure 1 As shown, the heat dissipation device 110 is independent of the electronic device 100 and can be mounted outside the electronic device 100. The heat that can be conducted to the outside of the electronic device is carried away by the airflow generated by the fan through mechanical components that accelerate the flow of air, such as a fan.

[0041] However, the heat dissipation device 110 is usually large in size. Even if it is installed in the electronic device 100, the space in the internal cavity of the electronic device 100 needs to be large enough so that the heat dissipation device 110 can be installed in the internal cavity of the electronic device. This will greatly reduce the portability of the electronic device, making it difficult to apply the heat dissipation device 110 to some small devices (such as mobile terminals), and the heat dissipation efficiency of this solution is low.

[0042] In addition, the art also proposes to meet the heat dissipation requirements of electronic devices through a liquid cooling system. Although this solution can improve the heat dissipation efficiency of electronic devices to a certain extent, the design of this solution is relatively complex and the use environment is limited, making it difficult to directly install the liquid cooling system inside the electronic device.

[0043] In view of this, an embodiment of the present application proposes a heat dissipation device and an electronic device, wherein the heat dissipation device has a stronger heat dissipation capability and occupies a smaller space so as to be easily integrated into the interior of the electronic device.

[0044] Figure 2 is a schematic diagram of the structure of a heat dissipation device 200 proposed in an embodiment of the present application. Figure 2 (a) is a cross-sectional view of the heat dissipation device 200, and the cross-sectional view is obtained based on a first cross-sectional view, and the first cross-sectional view is perpendicular to the heat dissipation device 200; Figure 2(b) is a cross-sectional view of the heat dissipation device 200, which is obtained based on the second cross-sectional view, and the second cross-sectional view is parallel to the horizontal plane on which the heat dissipation device 200 is set.

[0045] refer to Figure 2 As shown, the heat dissipation device 200 includes:

[0046] A heat-conducting layer 210 , wherein the heat-conducting layer 210 covers the heat-dissipating target 201 ;

[0047] A heat dissipation layer 220 , the heat dissipation layer 220 is located on a side of the heat conductive layer 210 away from the heat dissipation target 201 ;

[0048] The packaging layer 230 is located on a side of the heat dissipation layer 220 away from the heat dissipation target 201;

[0049] Among them, the heat dissipation layer 220 includes multiple chamber walls 221 and multiple cantilever structures 222, the multiple chamber walls 221 are arranged side by side and supported between the thermal conductive layer 210 and the packaging layer 230, the multiple cantilever structures 222 are fixed to at least one chamber wall 221, and the cantilever structures 222 include piezoelectric materials, and the piezoelectric materials vibrate based on the alternating electric field.

[0050] Among them, the piezoelectric material can convert mechanical pressure into a charge signal or convert an electric field into mechanical motion, thereby realizing the function of the cantilever structure 222 vibrating based on an alternating electric field.

[0051] In some possible embodiments, the heat dissipation target 201 may be an electronic device in an electronic device, a circuit board, or a part of a circuit board.

[0052] In some possible embodiments, the thermal conductive layer 210 and the heat dissipation target 201 may be fixed by adhesive, or may be fixed by bonding based on other materials, or may be fixed by mechanical structure, or may be fixed by chemical bonding, etc.

[0053] In some possible embodiments, the piezoelectric material may include one or more of piezoelectric ceramics (PZT), quartz, sodium potassium niobate, lithium aluminate and other similar materials. Using materials with higher electromechanical coupling coefficients can make the piezoelectric material have a stronger ability to convert electrical energy into mechanical energy.

[0054] In some possible embodiments, the chamber wall 221 may include silicon nitride or other semiconductor materials.

[0055] refer to Figure 2As shown in (b), the cross-sectional view is a cross-sectional view of the heat dissipation layer 220 obtained based on the second cross-sectional view, and the unfilled background in the cross-sectional view of the heat dissipation layer 220 is used to represent the upper surface of the heat conductive layer 210. In this example, the heat dissipation layer 220 may include two chamber walls 221 arranged side by side, and the two chamber walls 221, the heat conductive layer 210 and the packaging layer 230 together construct an air channel 202 (also referred to as a chamber), and the above-mentioned multiple cantilever structures 222 are distributed in the air channel 202. In the process of the cantilever structure 222 including piezoelectric material vibrating based on the alternating current electric field, a fan force is generated on the air in the chamber space, thereby promoting the flow of airflow in the chamber space, and then taking away the heat from the heat dissipation target 201 through the airflow.

[0056] In some possible embodiments, the cantilever structure may be referred to as a cantilever structure, and may be a cantilever beam, a cantilever plate, or the like.

[0057] In some possible embodiments, the vibration direction of the cantilever structure 222 is the same as or similar to the extension direction of the air channel 202 between the two chamber walls 221, thereby ensuring the smoothness of air flow and increasing heat dissipation efficiency.

[0058] In some possible embodiments, the thermal conductive layer may be prepared based on a metal material with high thermal conductivity. The thermal conductive layer may include metal materials conventionally processed for semiconductors such as aluminum, copper, and molybdenum, or may be a semiconductor material with high thermal conductivity, such as silicon nitride.

[0059] In some possible embodiments, the packaging layer may include a material with good sealing properties such as polyimide, so as to achieve the effect of packaging and protecting the heat dissipation device 200 as a whole.

[0060] In some possible embodiments, the heat conducting layer 210 includes a plurality of first grooves 211 , and / or the packaging layer 230 includes a plurality of second grooves 231 .

[0061] In some possible embodiments, the structural shape of the thermal conductive layer 210 and the structural shape of the packaging layer 230 are symmetrical based on the heat dissipation layer 220 .

[0062] For example, the thickness of each layer of the heat dissipation device 200 can be designed as follows: the heat conduction layer 210 accounts for 20% of the thickness of the overall film structure, the heat dissipation layer 220 accounts for 50% of the thickness of the overall film structure, and the encapsulation layer 230 accounts for 30% of the thickness of the overall film structure. This thickness is only an example, and in actual production, the thickness relationship between the layers can be adaptively adjusted.

[0063] In some possible embodiments, since the heat dissipation device 200 proposed in the embodiment of the present application is a film layer structure, the thickness of the above-mentioned thermal conductive layer 210, heat dissipation layer 220 and packaging layer 230 can be below the millimeter level (for example, millimeter level, micrometer level, nanometer level), so that it is easier to integrate into small or even micro electronic devices.

[0064] In some possible embodiments, the distance between the multiple cantilever structures 222 is greater than or equal to a distance threshold, thereby effectively preventing the multiple cantilever structures 222 from colliding when vibrating, generating noise, and reducing heat dissipation efficiency.

[0065] Based on the above technical solution, through a special membrane structure design, multiple cantilever structures including piezoelectric materials in the chamber wall vibrate based on the AC electric field, thereby promoting the flow of air in the cavity formed between two adjacent chamber walls, and taking away the heat emitted by the heat dissipation target through the airflow, thereby playing a heat dissipation role. Since the heat dissipation device is a tiny membrane structure and occupies very little space, it can be integrated in electronic equipment and directly contact the heat dissipation target, so it can further improve the heat dissipation efficiency.

[0066] Figure 2 (b) shows a structural diagram of a heat dissipation layer 220. In addition, the structure of the heat dissipation layer 220 may also include a variety of structural deformations.

[0067] Figure 3 It is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application.

[0068] refer to Figure 3 As shown, the heat dissipation layer 220 may include three chamber walls 221 , which are referred to as a first chamber wall 221 - 1 , a second chamber wall 221 - 2 and a third chamber wall 221 - 3 .

[0069] The air channel 202 formed between the first chamber wall 221-1 and the second chamber wall 221-2 is recorded as the first air channel 202-1, and the air channel 202 formed between the second chamber wall 221-2 and the third chamber wall 221-3 is recorded as the second air channel 202-2. Accordingly, the plurality of cantilever structures 222 are distributed in the first air channel 202-1 and the second air channel 202-2.

[0070] In some possible embodiments, reference Figure 3As shown, a part of the cantilever structures 222 can be distributed on the side of the second chamber wall 221-2 close to the first chamber wall 221-1, and another part of the cantilever structures 222 can be distributed on the side of the second chamber wall 221-2 close to the third chamber wall 221-3. The multiple cantilever structures 222 distributed in the first air channel 202-1 and the multiple cantilever structures 222 distributed in the second air channel 202-2 correspond to different positions of the second chamber wall 221-2, respectively, to avoid the situation where two cantilever structures 222 are separated by only one second chamber wall 221-2, in which case the vibrations of the two cantilever structures 222 are likely to affect each other.

[0071] In some possible embodiments, the numbers of the cantilever structures 222 distributed in the two air passages 202 may be the same.

[0072] In some possible embodiments, the intervals between the multiple cantilever structures 222 located in the same air channel 202 may be the same.

[0073] Figure 4 It is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application.

[0074] refer to Figure 4 As shown, the heat dissipation layer 220 may include three chamber walls 221, which are recorded as the first chamber wall 221-1, the second chamber wall 221-2 and the third chamber wall 221-3. The air channel 202 formed between the first chamber wall 221-1 and the second chamber wall 221-2 is recorded as the first air channel 202-1, and the air channel 202 formed between the second chamber wall 221-2 and the third chamber wall 221-3 is recorded as the second air channel 202-2. Accordingly, the above-mentioned multiple cantilever structures 222 are distributed in the first air channel 202-1 and the second air channel 202-2.

[0075] and Figure 3 The heat dissipation layer 220 shown is different in that Figure 4 The heat dissipation layer 220 shown is designed with openings for the air channels 202 .

[0076] Two adjacent chamber walls 221 form an air channel 202 , and the air channel 202 includes a first opening 03 and a second opening 04 , wherein the caliber of the first opening 03 is greater than or equal to the caliber of the second opening 04 .

[0077] For example, the first opening 03 and the second opening 04 may be a tapered structure. According to the law of conservation of mass in fluid flow, when the airflow passes through the tapered structure, the airflow velocity will increase to maintain mass conservation due to the gradual reduction of the aperture of the through hole. Since the aperture of the first opening 03 is greater than or equal to the aperture of the second opening 04, the first opening 03 may be used as an air inlet, and the second opening 04 may be an air outlet.

[0078] For example, Figure 4 As shown, the first chamber wall 221-1 and the third chamber wall 221-3 are planar structures, the second chamber wall 221-2 is a folded surface structure, and the second chamber wall 221-2 may include an end A, a middle portion B, and an end C, wherein the end A is bent at a specified angle along a first direction D1 compared to the middle portion B, and the end C is bent at a specified angle along a second direction D2 compared to the middle portion B, the first direction D1 is opposite to the second direction D2, and the middle portion B may be parallel to the first chamber wall 221-1 and the third chamber wall 221-3. Based on this, the opening formed between the end A and the end D of the first chamber wall 221-1 may be the above-mentioned first opening 03, and presents a tapered structure, and the opening formed between the end C and the end E of the first chamber wall 221-1 may be the above-mentioned second opening 04, and presents a tapered structure.

[0079] Similarly, the opening formed between end A and end F of the third chamber wall 221-3 can be the above-mentioned second opening 04 and have a tapered structure, and the opening formed between end C and end G of the third chamber wall 221-3 can be the above-mentioned first opening 03 and have a tapered structure.

[0080] Based on the above structure, the circulation speed of the airflow can be further improved. The airflow direction of the first air channel 202-1 is opposite to the airflow direction of the second air channel 202-2, which helps to more comprehensively remove the heat emitted by the heat dissipation target 201, thereby further improving the heat dissipation effect of the heat dissipation device 200.

[0081] Figure 5 It is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application.

[0082] refer to Figure 5 As shown, the heat dissipation layer 220 may include three chamber walls 221 , which are referred to as a first chamber wall 221 - 1 , a second chamber wall 221 - 2 and a third chamber wall 221 - 3 . Figure 5 The structure of the heat dissipation layer 220 is shown in FIG. Figure 4 The heat dissipation layer 220 shown is similar, and the only difference in structure is the shape of the end A and the end C of the second chamber wall 221-2, which are in the form of a right triangle. For the end A, the right angle side of the right triangle is opposite to the end D of the first chamber wall 221-1, and the hypotenuse of the right triangle is opposite to the end F of the third chamber wall 221-3; for the end C, the right angle side of the right triangle is opposite to the end E of the first chamber wall 221-1, and the hypotenuse of the right triangle is opposite to the end G of the third chamber wall 221-3. Of course, the shape of the end of the second chamber wall 221-2 can also be other shapes.

[0083] Based on the above structure, the etching operation on the second chamber wall 221 - 2 can be reduced during the preparation process, thereby reducing the manufacturing difficulty and reducing the etching time.

[0084] Figure 6 It is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application.

[0085] refer to Figure 6 As shown, the heat dissipation layer 220 may include two chamber walls 221 , which are referred to as a first chamber wall 221 - 1 and a second chamber wall 221 - 2 .

[0086] The air passage 202 formed between the first chamber wall 221 - 1 and the second chamber wall 221 - 2 is wider, and a plurality of cantilever structures 222 are respectively arranged on the first chamber wall 221 - 1 and the second chamber wall 221 - 2 in opposition to each other.

[0087] Based on the above structure, the number of etching holes reserved during the preparation process can be reduced, thereby reducing the difficulty of production.

[0088] Figure 7 It is a structural diagram of another heat dissipation layer 220 proposed in an embodiment of the present application.

[0089] refer to Figure 7 As shown, the heat dissipation layer 220 may include two chamber walls 221, which are referred to as a first chamber wall 221-1 and a second chamber wall 221-2. Figure 6 The heat dissipation layer 220 shown is different in that Figure 7 The heat dissipation layer 220 shown is designed with openings for the air channels 202 .

[0090] like Figure 7 As shown, both the first chamber wall 221-1 and the second chamber wall 221-2 are folded surface structures, the first chamber wall 221-2 may include an end D, a middle portion H and an end E, and the second chamber wall 221-2 may include an end A, a middle portion B and an end C, wherein the end A is bent at a specified angle along the first direction D1 compared to the middle portion B, the end C is bent at a specified angle along the second direction D2 compared to the middle portion B, the end D is bent at a specified angle along the first direction D1 compared to the middle portion H, the end E is bent at a specified angle along the second direction D2 compared to the middle portion H, the first direction D1 is opposite to the second direction D2, and the middle portion B may be parallel to the middle portion H. Based on this, the opening formed between the end A and the end D may be the above-mentioned first opening 03, and presents a tapered structure, and the opening formed between the end C and the end E may be the above-mentioned second opening 03, and presents a tapered structure.

[0091] Based on the above structure, the circulation speed of the airflow can be further increased, thereby improving the heat dissipation effect of the heat dissipation device 200.

[0092] Figure 8 2 is a schematic diagram of a cantilever structure 222 proposed in an embodiment of the present application. Figure 8 2 is a cross-sectional view of the cantilever structure 222 based on a third cross section which is perpendicular to the chamber wall 221 to which the cantilever structure 222 is fixed.

[0093] refer to Figure 8 As shown, the cantilever structure 222 includes: a cantilever body 2221 and a first piezoelectric material layer 2222 , wherein the first piezoelectric material layer 2222 covers at least a portion of the first side surface 01 of the cantilever body 2221 .

[0094] In some possible embodiments, the cantilever structure 222 may further include: a first grounding electrode 2224 located on a side of the first piezoelectric material layer 2222 away from the cantilever body 2221 ; and a first driving electrode 2225 located between the first piezoelectric material layer 2222 and the cantilever body 2221 .

[0095] In some possible embodiments, the first driving electrode 2225 may be embedded in the first piezoelectric material layer 2222 .

[0096] Based on the above technical solution, the first piezoelectric material layer can vibrate based on the AC electric field. Since the first piezoelectric material layer is laid on the first side of the cantilevered body, it can drive the cantilevered body to vibrate to promote airflow in the airway and accelerate heat dissipation.

[0097] Fig. 9 It is a structural schematic diagram of another cantilever structure 222 proposed in an embodiment of the present application.

[0098] refer to Fig. 9 As shown, the cantilever structure 222 includes: a cantilever body 2221 , a first piezoelectric material layer 2222 and a second piezoelectric material layer 2226 , and the second piezoelectric material layer 2226 covers at least a portion of the second side surface 02 of the cantilever body 2221 .

[0099] In some possible embodiments, the cantilever structure 222 may further include: a second grounding electrode 2227 located on a side of the second piezoelectric material layer 2226 away from the cantilever body 2221 ; and a second driving electrode 2228 located between the second piezoelectric material layer 2226 and the cantilever body 2221 .

[0100] In some possible embodiments, the second ground electrode 2227 may be embedded in the cantilever body 2221 , and the second driving electrode 2228 may be embedded in the second piezoelectric material layer 2226 .

[0101] Based on the above technical solution, laying the first piezoelectric material layer and the second piezoelectric material layer on the two sides of the cantilevered body respectively can further increase the vibration intensity of the cantilevered body, thereby further promoting the airflow in the airway and accelerating the heat dissipation.

[0102] In some possible embodiments, the first piezoelectric material layer 2222 may cover from the free end of the cantilever body 2221 to the fixed end of the cantilever body 2221, wherein the free end is an end of the cantilever body 2221 suspended in the air, and the fixed end is an end of the cantilever body 2221 fixed to the chamber wall 221. Based on this, it is helpful for the cantilever body 2221 to receive the vibration force from the first piezoelectric material layer 2222 more evenly.

[0103] In some possible embodiments, the second piezoelectric material layer 2226 may cover from the free end of the cantilever body 2221 to the fixed end of the cantilever body 2221. Based on this, it helps the cantilever body 2221 to receive the vibration force from the second piezoelectric material layer 2226 more evenly.

[0104] In some possible embodiments, based on any one of the cantilever structures 222 proposed in the aforementioned embodiments, the cantilever structure 222 may further include a counterweight portion 2223 , and the counterweight portion 2223 is located at the free end of the cantilever body 2221 .

[0105] Fig.10 2 is a schematic diagram of another cantilever structure 222 proposed in the embodiment of the present application. Fig.10 (a) is used to provide a schematic diagram of the position of the counterweight portion 2223 in the cantilever structure 222. Fig.10 (b) is used to provide another schematic diagram of the position of the counterweight part 2223 in the cantilever structure 222.

[0106] In some possible embodiments, reference Fig.10 In (a), the fixing surface between the counterweight portion 2223 and the cantilever body 2221 may be located at the midline position of the counterweight portion 2223 .

[0107] In some possible embodiments, reference Fig.10 In (b), the fixing surface between the counterweight portion 2223 and the cantilever body 2221 may deviate from the centerline position of the counterweight portion 2223 .

[0108] It should be noted that the counterweight 2223 can not only increase the weight of the cantilever body 2221, but also change the stress state of the cantilever body 2221, thereby affecting the deformation and displacement of the cantilever body 2221. When the cantilever body 2221 vibrates, the counterweight 2223 is driven to move, which can increase the contact area between the cantilever structure 222 and the surrounding air, thereby helping to improve the heat dissipation efficiency.

[0109] Based on the above technical solution, the heat dissipation efficiency of the heat dissipation device can be further improved.

[0110] In some possible embodiments, reference Figure 2 As shown, the heat dissipation device 200 may further include:

[0111] An AC power source 240 is connected to at least one driving electrode included in the cantilever structure 222 .

[0112] In some possible embodiments, the cantilever structure 222 includes the first driving electrode 2225 and the second driving electrode 2228 , and the AC power supply 240 may be configured to perform separate power supply control on the first driving electrode 2225 and the second driving electrode 2228 .

[0113] For example, the heat dissipation device 200 includes two heat dissipation gears. In the first gear, the AC power supply 240 can be controlled to supply AC power to the first driving electrode 2225 or the second driving electrode 2228; in the second gear, the AC power supply 240 can be controlled to supply AC power to the first driving electrode 2225 and the second driving electrode 2228.

[0114] For example, the heat dissipation device 200 includes two heat dissipation gears, and the AC power supply 240 may include a first sub-power supply and a second sub-power supply, wherein the first sub-power supply is connected to the first driving electrode 2225, and the second sub-power supply is connected to the second driving electrode 2228. In the first gear, the first sub-power supply may be controlled to start to supply power to the first driving electrode 2225, or the second sub-power supply may be controlled to start to supply power to the second driving electrode 2228; in the second gear, the first sub-power supply may be controlled to start to supply power to the first driving electrode 2225, and the second sub-power supply may be controlled to start to supply power to the second driving electrode 2228.

[0115] In some possible embodiments, the operating frequency of the AC power source 240 is greater than or equal to 20 kHz.

[0116] It should be understood that, because the maximum frequency of sound that can be perceived by the human ear is 20 kHz, the operating frequency of the AC power source 240 is designed to be greater than or equal to 20 kHz.

[0117] In some possible embodiments, the setting of the operating frequency of the AC power source 240 is related to the material and geometric parameters of the cantilever structure 222 .

[0118] Based on the above technical solution, the operating frequency of the AC power supply is designed to be greater than or equal to 20 kHz, so that the frequency of the cantilever structure vibrating based on the AC electric field is maintained at greater than or equal to 20 kHz, so that the human ear cannot perceive the sound emitted by the vibration of the cantilever structure, thereby effectively reducing the operating noise of the heat dissipation device.

[0119] In some possible embodiments, the cantilever structure 222 may also include a PMUT or a CMUT, that is, the PMUT or the CMUT is suspended on the chamber wall 221 .

[0120] The embodiment of the present application also proposes a method for preparing a heat dissipation device, which is used to prepare the heat dissipation device 200 proposed in the embodiment of the present application.

[0121] Fig.11 It is a flow chart of a method 1100 for preparing a heat dissipation device proposed in an embodiment of the present application.

[0122] In this example, the method 1100 is used to prepare a Fig. 9 The heat sink 200 with the cantilever structure 222 shown in the figure can be prepared in a similar manner for heat sinks with other structures, and only the operations of the specified steps need to be fine-tuned according to the needs, which will not be described in detail here. The method 1100 includes the following steps:

[0123] S1110: Depositing or evaporating an encapsulation layer on the glass substrate.

[0124] S1120: depositing or evaporating a filling layer on the packaging layer.

[0125] The filling ring layer may include a material for being etched, which may be a metal material or a non-metal material. The specific material used may be different from that of other material layers, because the filling ring layer needs to be etched away later.

[0126] S1130: depositing a first silicon nitride support on the outer ring of the filling ring layer.

[0127] Wherein, the first silicon nitride support may include the chamber wall.

[0128] S1140: A second silicon nitride support, a first grounding electrode metal, a first piezoelectric material, a first driving electrode metal, a silicon nitride package, a second driving electrode metal, a second piezoelectric material, a second grounding electrode metal and a third silicon nitride support are deposited in sequence along the horizontal direction on the inner circle of the filling layer, and etching holes are reserved at the electrode positions, and then the remaining space of the inner circle of the filling layer is filled with the etched material.

[0129] Among them, the bottom opening of the reserved etching hole needs to be away from the position of the electrode (metal) to reduce the risk of short circuit between electrodes due to the diffusion of impurities, residues or etchants that may be generated during the etching process, which helps to maintain electrical isolation between electrodes and ensure the normal function of the device.

[0130] In addition, the second silicon nitride support, the silicon nitride package and the third silicon nitride support may include the above-mentioned cantilever structure, and the second silicon nitride support, the silicon nitride package and the third silicon nitride support may also isolate the electrode metal and the piezoelectric material from the filling ring layer.

[0131] S1150: depositing or evaporating a thermal conductive layer on the silicon nitride support deposited on the outer ring of the filling ring layer, and reserving etching holes.

[0132] The heat conducting layer may be metal or other heat conducting materials.

[0133] S1160: Pour an etching solution through the etching hole, and the etching solution is used to etch away the filling ring layer until the electrode is exposed.

[0134] S1170: peeling the overall structure prepared above from the glass substrate.

[0135] The embodiment of the present application further provides an electronic device, which includes the above-mentioned heat dissipation target 201 and any one of the heat dissipation devices 200 provided in the embodiment of the present application.

[0136] In some possible embodiments, the electronic device may be any terminal device having a need for heat dissipation during operation, such as a TV set, a monitoring screen, an independent display, a laptop computer, a tablet computer, a smart phone, etc.

[0137] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0138] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0139] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A heat dissipation device, characterized in that: include: a heat-conducting layer, the heat-conducting layer covering a heat-dissipating target; a heat dissipation layer, the heat dissipation layer being located on a side of the heat conductive layer away from the heat dissipation target; an encapsulation layer, the encapsulation layer being located on a side of the heat dissipation layer away from the heat dissipation target; Among them, the heat dissipation layer includes a plurality of chamber walls and a plurality of cantilever structures, the plurality of chamber walls are arranged side by side and supported between the thermal conductive layer and the packaging layer, the plurality of cantilever structures are fixed to at least one of the plurality of chamber walls, and the cantilever structures include piezoelectric material, and the piezoelectric material vibrates based on an alternating electric field.

2. The heat dissipation device according to claim 1, characterized in that: The cantilever structure includes a cantilever body and a first piezoelectric material layer, wherein the first piezoelectric material layer covers at least a portion of a first side surface of the cantilever body.

3. The heat dissipation device according to claim 2, characterized in that: The cantilever structure further includes a counterweight portion, and the counterweight portion is located at a free end portion of the cantilever body.

4. The heat dissipation device according to claim 2 or 3, characterized in that: The cantilever structure further comprises: a first grounding electrode, the first grounding electrode being located on a side of the first piezoelectric material layer away from the cantilevered body; A first driving electrode is located between the first piezoelectric material layer and the cantilever body.

5. The heat dissipation device according to claim 4, characterized in that: The heat dissipation device also includes: An alternating current power source is electrically connected to the first driving electrode.

6. The heat dissipation device according to claim 5, characterized in that: The operating frequency of the AC power supply is greater than or equal to 20 kHz.

7. The heat dissipation device according to claim 5 or 6, characterized in that: The cantilever structure further includes a second piezoelectric material layer covering at least a portion of a second side surface of the cantilever body.

8. The heat dissipation device according to claim 7, characterized in that: The cantilever structure further comprises: a second grounding electrode, the second grounding electrode being located on a side of the second piezoelectric material layer away from the cantilevered body; A second driving electrode, wherein the second driving electrode is located between the second piezoelectric material layer and the cantilever body, and the second driving electrode is electrically connected to the AC power source.

9. The heat dissipation device according to any one of claims 1 to 8, characterized in that: Two adjacent chamber walls form an air channel, and the air channel includes a first opening and a second opening. The caliber of the first opening is greater than or equal to the caliber of the second opening.

10. The heat dissipation device according to any one of claims 1 to 9, characterized in that: The heat conducting layer includes a plurality of first grooves, and / or the packaging layer includes a plurality of second grooves.

11. The heat dissipation device according to claim 1, characterized in that: The cantilever structure includes a piezoelectric micromachined ultrasonic transducer PMUT or a capacitive micromachined ultrasonic transducer CMUT.

12. The heat dissipation device according to any one of claims 1 to 11, characterized in that: The distance between the multiple cantilever structures is greater than or equal to a distance threshold.

13. The heat dissipation device according to any one of claims 1 to 12, characterized in that: The thickness of the thermal conductive layer, the heat dissipation layer and the packaging layer is below millimeter level.

14. An electronic device, characterized in that: The invention comprises a heat dissipation target and a heat dissipation device as claimed in any one of claims 1 to 13.

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