CN112135488A

CN112135488A - Heat conduction structure, preparation method thereof and electronic equipment

Info

Publication number: CN112135488A
Application number: CN202011020180.1A
Authority: CN
Inventors: 程志政
Original assignee: Nanchang OFilm Display Technology Co Ltd
Current assignee: Jiangxi Xinfei New Material Co ltd
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2020-12-25

Abstract

The invention discloses a heat conduction structure, a preparation method thereof and electronic equipment. A plurality of communicated capillary grooves are formed in the first heat conducting sheet, and the second heat conducting sheet is connected to the first heat conducting sheet in a sealing mode, so that a sealing cavity for heat conducting fluid to circulate is formed between the first heat conducting sheet and the second heat conducting sheet through the plurality of capillary grooves in the first heat conducting sheet. The mode that forms a plurality of capillary grooves on first heat-conducting plate is adopted, utilizes capillary groove can form the seal chamber who supplies the heat-conducting fluid circulation to capillary groove can provide capillary force, need not additionally to increase fibre or weave the copper mesh, thereby can effectively reduce heat conduction structure's whole thickness, makes it can satisfy electronic equipment's frivolous design requirement.

Description

Heat conduction structure, preparation method thereof and electronic equipment

Technical Field

The invention relates to the technical field of heat dissipation structures, in particular to a heat conduction structure, a preparation method of the heat conduction structure and electronic equipment.

Background

With the development of science and technology, the processing functions of electronic devices in electronic equipment become more and more powerful, and the power consumption and the heat productivity of the electronic equipment also become higher and higher. In the related art, in order to consider the light and thin design of electronic devices, a VC (vacuum Chamber Vapor Chamber) heat conducting plate is often used to dissipate heat of electronic devices (such as chips, batteries, etc.), the VC heat conducting plate mainly includes an upper heat conducting sheet and a lower heat conducting sheet, a working cavity is formed between the upper heat conducting sheet and the lower heat conducting sheet, and then a fiber or woven copper mesh is laid between the upper heat conducting sheet and the lower heat conducting sheet, and holes on the fiber or woven copper mesh are communicated with the working cavity, so that a capillary structure for guiding heat conducting fluid is formed by using the fiber or woven copper mesh. However, in this way, on one hand, the fiber or the woven copper mesh has a certain thickness, which results in the increase of the overall thickness of the VC heat conducting plate and fails to meet the light and thin design requirements of the electronic device, and on the other hand, the increase of the fiber or the woven copper mesh has high processing difficulty, often needs manual work to make with the aid of a jig, and has low manufacturing efficiency and precision.

Disclosure of Invention

The embodiment of the invention discloses a heat conduction structure, a preparation method thereof and electronic equipment, which can effectively reduce the manufacturing difficulty of the heat conduction structure, improve the manufacturing efficiency and the manufacturing precision, reduce the overall thickness and meet the requirement of miniaturization design of the electronic equipment.

In order to achieve the above object, in a first aspect, the present invention discloses a heat conductive structure comprising

The first heat conducting sheet is provided with a plurality of communicated capillary grooves; and

the second heat conducting sheet is connected to the first heat conducting sheet in a sealing mode, so that a sealing cavity for heat conducting fluid to flow is formed between the first heat conducting sheet and the second heat conducting sheet by the capillary grooves in the first heat conducting sheet, the sealing cavity is provided with an evaporation heat absorption area, a diffusion area and a condensation heat release area, the evaporation heat absorption area is arranged corresponding to a heat source and used for absorbing heat emitted by the heat source, the diffusion area is located between the evaporation heat absorption area and the condensation heat release area, and the diffusion area is used for diffusing the heat in the evaporation heat absorption area to the condensation heat release area.

The first heat conducting sheet is provided with a plurality of communicated capillary grooves, and the capillary grooves can directly form a sealed cavity for the circulation of heat conducting fluid, so that fibers or woven copper meshes do not need to be additionally added, the overall thickness of the heat conducting structure is effectively reduced, and the light and thin design requirements of electronic equipment can be met. In addition, the capillary grooves are formed in the first heat conducting plate, the processing difficulty of the heat conducting structure can be reduced, meanwhile, alignment is not needed, and the manufacturing precision and the manufacturing efficiency of the heat conducting structure are effectively improved.

In addition, the sealing cavity is divided into the evaporation heat absorption area, the diffusion area and the condensation heat release area, and the diffusion area is located between the evaporation heat absorption area and the condensation heat release area, so that heat absorbed by the evaporation heat absorption area can be rapidly diffused to the condensation heat release area for cooling by the diffusion area, rapid cooling and heat dissipation can be realized, and the heat dissipation effect of the heat conduction structure is improved.

As an alternative implementation, in an embodiment of the first aspect of the invention, the diffusion zone is formed as a cavity in a region close to the vaporization heat-absorption zone. Therefore, the diffusion area can be favorable for rapidly diffusing heat, and the heat is prevented from being gathered at the evaporation heat absorption area, so that the diffusion speed of the heat is improved.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the arrangement density of the capillary grooves in the diffusion region gradually increases from the position close to the evaporation heat absorption region to the position away from the evaporation heat absorption region. Therefore, the diffusion area is far away from the position of the evaporation heat absorption area, the arrangement density of the capillary grooves is high, and the capillary grooves are provided, so that heat can be cooled, the diffusion speed and the condensation speed of the heat are improved, and the effects of quickly radiating and cooling are achieved.

In addition, the arrangement density of the capillary grooves of the diffusion area at the position far away from the evaporation heat absorption area is higher, and the arrangement density of the supporting parts of the first heat conducting sheets for forming the capillary grooves is also higher, so that the diffusion area has certain supporting strength, and the situation that the first heat conducting sheets collapse due to insufficient support at the position corresponding to the diffusion area is avoided.

As an alternative implementation manner, in an embodiment of the first aspect of the present invention, the diffusion region has a first diffusion region near the evaporation heat absorption region and a second diffusion region near the condensation heat release region, and a width of the second diffusion region is greater than a width of the first diffusion region. Since the diffusion region has a cavity structure near the evaporation heat absorption region, that is, the overall structural strength of the first diffusion region near the evaporation heat absorption region is weaker than that of the second diffusion region near the condensation heat release region, in order to effectively ensure the structural strength of the first diffusion region and avoid the occurrence of a sag condition under a vacuum negative pressure condition, the width of the first diffusion region should be smaller than that of the second diffusion region.

As an optional implementation manner, in an embodiment of the first aspect of the present invention, the width of the first diffusion region is 0.5mm to 5mm, and the width of the second diffusion region is 0.5mm to 5mm, so that the widths of the first diffusion region and the second diffusion region are reasonable, the structural strength of the diffusion region can be effectively ensured, and the occurrence of a depression condition due to insufficient support under a vacuum negative pressure condition can be avoided.

As an alternative implementation manner, in an embodiment of the first aspect of the present invention, the first heat conducting sheet is an elongated sheet, and the evaporation heat absorption region, the diffusion region, and the condensation heat release region are sequentially disposed along a length direction of the first heat conducting sheet. So that the diffusion zone can be positioned between the condensation heat-release zones to realize rapid heat diffusion to the condensation heat-release zones.

As an alternative implementation manner, in the embodiment of the first aspect of the present invention, among the capillary grooves located in the evaporation heat absorption region and close to the diffusion region and the capillary grooves located in the condensation heat release region and close to the diffusion region, there are connected grooves between two adjacent capillary grooves. Therefore, the heat-conducting fluid can circularly flow between the evaporation heat absorption area and the condensation heat release area back and forth, so that the fluid in the condensation heat release area can be effectively ensured to flow back to the evaporation heat absorption area for supplement in time, and the evaporation heat absorption area is prevented from being dried.

As an alternative implementation manner, in an embodiment of the first aspect of the present invention, the width of the groove is smaller than the width of the capillary groove, so that the heat-conducting fluid can flow from the groove to the adjacent capillary groove, and the circulation flow of the heat-conducting fluid is realized.

As an alternative implementation, in an embodiment of the first aspect of the invention, the depth of the capillary groove is greater than or equal to the width of the capillary groove. Thus, the capillary force of the capillary groove can be effectively ensured.

As an alternative implementation, in an embodiment of the first aspect of the present invention, the depth of the capillary groove is 30-200 μm, and the width of the capillary groove is 20-200 μm. Therefore, the width and the depth of the capillary groove are small, and the capillary effect can be realized.

As an alternative implementation, in the embodiment of the first aspect of the present invention, the cross-sectional shape of the capillary groove is an inverted triangle, an inverted trapezoid, a rectangle, a square, a circle, or an ellipse. The capillary groove with a circular, oval or polygonal section (such as inverted triangle, inverted trapezoid, rectangle or square) is adopted, so that the processing is convenient, the processing technology of the heat conduction structure is simplified, and the processing difficulty is reduced.

In a second aspect, the present invention also discloses a method for preparing a heat conducting structure, wherein the method comprises:

providing a first heat-conducting sheet, and forming a plurality of capillary grooves on the first heat-conducting sheet;

connecting a second heat conducting fin to the first heat conducting fin in a sealing mode, so that a plurality of capillary grooves in the first heat conducting fin form a sealed cavity for heat conducting fluid to flow between the first heat conducting fin and the second heat conducting fin;

the sealed cavity is provided with an evaporation heat absorption area, a diffusion area and a condensation heat release area, the evaporation heat absorption area is arranged corresponding to the heating source to absorb heat emitted by the heating source, the diffusion area is located between the evaporation heat absorption area and the condensation heat release area, and the diffusion area is used for diffusing the heat of the evaporation heat absorption area to the condensation heat release area. .

By adopting the preparation method, the capillary groove can be directly used for forming the sealed cavity for the circulation of the heat-conducting fluid, so that extra fibers or woven copper meshes are not needed, the overall thickness of the heat-conducting structure is effectively reduced, and the light and thin design requirements of electronic equipment can be met. In addition, the capillary grooves are formed in the first heat conducting plate, the processing difficulty of the heat conducting structure can be reduced, meanwhile, alignment is not needed, and the manufacturing precision and the manufacturing efficiency of the heat conducting structure are effectively improved.

In addition, the diffusion area is positioned between the evaporation heat absorption area and the condensation heat release area, and heat absorbed by the evaporation heat absorption area can be rapidly diffused to the condensation heat release area for cooling by the diffusion area, so that rapid cooling and heat dissipation can be realized, and the heat dissipation effect of the heat conduction structure is improved.

As an alternative implementation manner, in an embodiment of the second aspect of the present invention, the capillary groove is formed on the first heat-conducting plate by using a micro-etching process. The capillary groove is formed by the micro-etching process, so that the processing difficulty of the capillary groove can be reduced, and meanwhile, the alignment is not required, so that the preparation efficiency and the preparation precision of the heat conduction structure are effectively improved.

As an alternative implementation, in the embodiment of the second aspect of the present invention, the diffusion region is formed as a cavity in a region close to the evaporation heat absorption region. Therefore, the diffusion area can be favorable for rapidly diffusing heat, and the heat is prevented from being gathered at the evaporation heat absorption area, so that the diffusion speed of the heat is improved.

As an optional implementation manner, in an embodiment of the second aspect of the present invention, the arrangement density of the capillary grooves in the diffusion region gradually increases from the position close to the evaporation heat absorption region to the position far away from the evaporation heat absorption region. Therefore, the diffusion area is far away from the position of the evaporation heat absorption area, the arrangement density of the capillary grooves is high, the number of the capillary grooves is large, and heat can be cooled, so that the diffusion speed and the condensation speed of the heat are improved, and the effects of quickly radiating and cooling are achieved.

As an alternative implementation manner, in the embodiment of the second aspect of the present invention, the diffusion region has a first diffusion region near the evaporation heat absorption region and a second diffusion region near the condensation heat release region, and the width of the second diffusion region is greater than that of the first diffusion region. Since the diffusion region has a cavity structure near the evaporation heat absorption region, that is, the overall structural strength of the first diffusion region near the evaporation heat absorption region is weaker than that of the second diffusion region near the condensation heat release region, in order to effectively ensure the structural strength of the first diffusion region and avoid the occurrence of a depression condition under a vacuum negative pressure condition, the width of the first diffusion region is smaller than that of the second diffusion region.

In a third aspect, the present invention further discloses an electronic device, where the electronic device includes a heat source and the heat conducting structure according to the first aspect, and the heat conducting structure is connected to the heat source to dissipate heat of the heat source. Utilize heat conduction structure, can realize dispelling the heat fast to the source that generates heat of electronic equipment to can prevent to generate heat the source and lead to the problem that operational failure probably appears because of the high temperature, improve electronic equipment's use reliability. In addition, the heat conduction structure is adopted, the whole thickness is small, the occupied space of the electronic equipment is small, and the light and thin design requirements of the electronic equipment can be met.

Compared with the prior art, the invention has the beneficial effects that:

according to the heat conduction structure, the preparation method thereof and the electronic equipment, the plurality of communicated capillary grooves are formed on the first heat conduction sheet, and the capillary grooves can be used for directly forming the sealed cavity for the circulation of the heat conduction fluid, so that fibers or woven copper meshes are not required to be additionally added, the overall thickness of the heat conduction structure is effectively reduced, and the light and thin design requirements of the electronic equipment can be met. In addition, the capillary grooves are formed in the first heat conducting plate, the processing difficulty of the heat conducting structure can be reduced, meanwhile, alignment is not needed, and the manufacturing precision and the manufacturing efficiency of the heat conducting structure are effectively improved.

In addition, the sealed cavity is divided into the evaporation heat absorption area, the diffusion area and the condensation heat release area, and the diffusion area is located between the evaporation heat absorption area and the condensation heat release area, so that heat absorbed by the evaporation heat absorption area can be rapidly diffused to the condensation heat release area for cooling by the diffusion area, rapid cooling and heat dissipation can be realized, and the heat dissipation effect of the heat conduction structure is improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a heat conducting structure according to an embodiment of the disclosure;

FIG. 2 is an exploded view of a thermally conductive structure according to an embodiment of the present invention;

FIG. 3 is a top view of a first thermally conductive sheet according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a trench between two adjacent capillary grooves according to an embodiment of the disclosure;

FIG. 5 is a flow chart of a method for fabricating a thermally conductive structure according to a second embodiment of the present invention;

fig. 6 is a schematic structural diagram of an electronic device disclosed in the third embodiment of the present invention.

Icon: 100. a heat conducting structure; 10. a first thermally conductive sheet; 11. a capillary groove; 11a, sealing the cavity; 110. evaporating the heat absorption area; 111. a diffusion region; 111a, a first diffusion region; 111b, a second diffusion region; 111c, transition region; 112. a condensation heat release area; 113. a trench; 20. a second thermally conductive sheet; 600. an electronic device; 601. a heat generating source.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present invention, the terms "upper", "lower", "left", "right", "front", "rear", "top", "bottom", "inner", "outer", "center", "vertical", "horizontal", "lateral", "longitudinal", and the like indicate an orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These terms are used primarily to better describe the invention and its embodiments and are not intended to limit the indicated devices, elements or components to a particular orientation or to be constructed and operated in a particular orientation.

Moreover, some of the above terms may be used to indicate other meanings besides the orientation or positional relationship, for example, the term "on" may also be used to indicate some kind of attachment or connection relationship in some cases. The specific meanings of these terms in the present invention can be understood by those skilled in the art as appropriate.

Furthermore, the terms "mounted," "disposed," "provided," "connected," and "connected" are to be construed broadly. For example, it may be a fixed connection, a removable connection, or a unitary construction; can be a mechanical connection, or an electrical connection; may be directly connected, or indirectly connected through intervening media, or may be in internal communication between two devices, elements or components. The specific meanings of the above terms in the present invention can be understood by those of ordinary skill in the art according to specific situations.

Furthermore, the terms "first," "second," and the like, are used primarily to distinguish one device, element, or component from another (the specific nature and configuration may be the same or different), and are not used to indicate or imply the relative importance or number of the indicated devices, elements, or components. "plurality" means two or more unless otherwise specified.

The technical solution of the present invention will be further described with reference to the following embodiments and the accompanying drawings.

Example one

Referring to fig. 1 and fig. 2 together, fig. 1 is a schematic structural diagram of a heat conducting structure according to an embodiment of the present invention, and fig. 2 is an exploded schematic structural diagram of a heat conducting structure according to an embodiment of the present invention. The heat conducting structure disclosed in this embodiment is a VC (vacuum Chamber Vapor Chamber) heat conducting structure, and can be applied to electronic equipment to dissipate heat from a heat source (e.g., a chip, a battery, etc.) in the electronic equipment, so as to ensure normal operation of the electronic equipment. Specifically, the heat conductive structure 100 includes a first heat conductive sheet 10 and a second heat conductive sheet 20. The first heat conducting sheet 10 is formed with a plurality of capillary grooves 11, and the second heat conducting sheet 20 is hermetically connected to the first heat conducting sheet 10, so that the plurality of capillary grooves 11 on the first heat conducting sheet 10 form a sealed cavity 11a for flowing a heat conducting fluid (not shown) between the first heat conducting sheet 10 and the second heat conducting sheet 20.

Wherein the capillary groove 11 means a groove having a capillary force.

The mode that forms a plurality of capillary grooves 11 on first conducting strip 10 is adopted, utilize capillary groove 11 to form the sealed cavity 11a that supplies the heat conduction fluid circulation to capillary groove 11 can provide capillary force, need not additionally to increase fibre or weave the copper mesh, thereby can effectively reduce heat conduction structure 100's whole thickness, make it can satisfy electronic equipment's frivolous design requirement.

In addition, the capillary groove 11 is formed on the first heat conducting strip 10, the processing mode is simple, complex mechanical alignment is not needed, and meanwhile, manual assistance of a jig is not needed, so that the processing difficulty can be effectively reduced, and the preparation efficiency and the preparation precision of the heat conducting structure 100 are improved.

In some embodiments, the first heat conductive sheet 10 may be a circular sheet or an elongated sheet in order to match a heat source of an electronic device. For example, the first heat conduction sheet 10 is a strip-shaped sheet, and the first heat conduction sheet 10 may be a metal sheet, and may be a copper sheet, a stainless steel sheet, or the like. When forming this capillary groove 11 on first conducting strip 10, the mode of accessible microetching realizes to the processing degree of difficulty is low and need not artifical assistance tool and accomplish, is favorable to improving its machining efficiency and machining precision.

Alternatively, the thickness of the first thermally conductive sheet 10 may be approximately 50-200 μm, so that the overall thickness of the thermally conductive structure is very thin and occupies less space. Illustratively, the thickness of the first thermally conductive sheet 10 may be 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, or the like.

Further, the second heat conducting sheet 20 may also be a long sheet, and the second heat conducting sheet 20 may also be a metal sheet, such as a copper sheet, a stainless steel sheet, and the like, and the thickness of the second heat conducting sheet 20 may also be approximately 50-200 μm, that is, the overall thickness of the heat conducting structure of the embodiment is 100-400 μm, so that the overall thickness of the heat conducting structure is very thin and occupies a small space. Illustratively, the thickness of the second heat conduction sheet 20 may be 50 μm, 80 μm, 100 μm, 120 μm, 150 μm, 180 μm, 200 μm, or the like, and the overall thickness of the heat conduction structure may be 100 μm, 160 μm, 240 μm, 300 μm, 360 μm, 400 μm, or the like, so that the heat conduction structure of the present embodiment is formed as an ultra-thin heat conduction structure having a thickness of 400 μm or less. When the second heat conducting strip 20 is connected with the first heat conducting strip 10 in a sealing manner, the liquid can be filled into the second heat conducting strip 20 and the first heat conducting strip 10 in a pressing manner, so that the second heat conducting strip 20 is completely connected with the first heat conducting strip 10 in a sealing manner, and a vacuum negative pressure environment can be formed between the first heat conducting strip 10 and the second heat conducting strip 20.

In the related art of the VC heat conducting plate, a plurality of first grooves are usually formed in the first heat conducting sheet 10, a plurality of second grooves are formed in the second heat conducting sheet 20 corresponding to the plurality of first grooves in the first heat conducting sheet 10, each second groove and each first groove are aligned and pressed to form a sealed cavity 11a, and then a fiber or woven copper mesh is fixed between the first groove and the second groove. By adopting the mode, on one hand, the first heat conducting sheet 10 and the second heat conducting sheet 20 are respectively provided with the grooves, the groove forming processing cost is high, and meanwhile, when the sealing and laminating are carried out, each first groove and each second groove are required to be aligned accurately, the alignment precision requirement is high, and the alignment cost is high, so that the control of the processing cost of the VC heat conducting plate is not facilitated. On the other hand, fibers or woven copper meshes are required to be added after the groove is formed, so that the overall thickness of the VC heat-conducting plate is increased, the processing difficulty of the VC heat-conducting plate is also increased, and the preparation difficulty and the cost of the VC heat-conducting plate are increased.

In this way, in the present invention, the capillary groove 11 is formed in the first heat conductive sheet 10 by microetching, and the etching cost is low because the capillary groove 11 is provided only in the first heat conductive sheet 10. Meanwhile, the capillary grooves 11 can directly provide capillary force, extra fibers or woven copper meshes are not needed, the overall thickness of the heat conducting structure 100 can be controlled, the processing difficulty of the heat conducting structure 100 can be reduced, the preparation efficiency is improved, and the preparation cost is reduced. In addition, the second heat conducting strip 20 is not provided with a groove, so that alignment is not required during pressing, which is beneficial to further reducing the processing difficulty of the heat conducting structure 100 and facilitating processing.

In some embodiments, as shown in fig. 3 and 4, the cross-sectional shape of the capillary groove 11 may be circular, elliptical, or polygonal. Specifically, when the cross section of the capillary groove 11 is polygonal, it may be, for example, an inverted triangle, an inverted trapezoid, a rectangle, a square, or other polygonal shapes, such as a hexagon, an octagon, etc. The capillary groove 11 has a circular, elliptical or polygonal cross section, which facilitates the processing of the capillary groove 11, thereby simplifying the processing technique of the heat conducting structure 100 and reducing the processing difficulty.

Further, the depth of the capillary groove 11 is greater than or equal to the width of the capillary groove 11, so that the capillary force of the capillary groove 11 can be effectively ensured. Specifically, the depth of the capillary groove 11 may be 30 to 200 μm, and the width of the capillary groove 11 may be 20 to 200 μm. Since the depth of the capillary groove 11 is greater than or equal to the width of the capillary groove 11, for example, the depth of the capillary groove 11 may be set to 30 μm, 40 μm, 60 μm, 80 μm, 100 μm, 120 μm, 150 μm, 200 μm, or the like, and the width of the capillary groove 11 may be set to 20 μm, 40 μm, 70 μm, 110 μm, 130 μm, 200 μm, or the like. Thus, the width and depth of the capillary groove 11 are small, and the capillary effect can be effectively realized.

It should be noted that, since the capillary groove 11 is formed on the first heat-conducting sheet 10 by micro-etching, the depth of the capillary groove 11 during micro-etching needs to be mainly the entire thickness of the first heat-conducting sheet 10, and the etching depth of the capillary groove 11 should be smaller than the thickness of the first heat-conducting sheet 10 to prevent the capillary groove from etching through the first heat-conducting sheet 10. For example, when the thickness of the first heat conductive sheet 10 is 50 μm, the depth of the capillary groove 11 may be 30 μm, and when the thickness of the first heat conductive sheet 10 is 100 μm, the depth of the capillary groove 11 may be 30 μm, 50 μm, 70 μm, or the like, as long as it is smaller than the thickness of the first heat conductive sheet 10.

In some embodiments, as can be seen from the foregoing, the first heat conducting sheet 10 is a strip-shaped sheet, and taking the first heat conducting sheet 10 as an approximately oval sheet as an example, the capillary groove 11 may be disposed on the first heat conducting sheet 10 in a ring shape along the outer shape of the first heat conducting sheet 10. Illustratively, as shown in fig. 3, a plurality of capillary grooves 11 are formed in the first heat conducting sheet 10 (the filled portions in fig. 3 indicate portions of the first heat conducting sheet 10 where no capillary groove 11 is formed, the portions can be press-fit connected with the second heat conducting sheet 20, and serve as support portions, and the blank portions between two adjacent filled portions in fig. indicate capillary grooves 11), the plurality of capillary grooves 11 are all annular grooves, each capillary groove 11 is circumferentially formed along the outer shape of the first heat conducting sheet 10, and each capillary groove 11 is sequentially arranged along the center of the first heat conducting sheet 10 at intervals outwards, so that the first heat conducting sheet 10 still has sufficient support to be press-fit connected with the second heat conducting sheet 20, and the first heat conducting sheet 10 is prevented from being concave when the vacuum negative pressure occurs due to insufficient support. In addition, with the above arrangement, it is not necessary to additionally provide a support structure on the first thermally conductive sheet 10 to support the second thermally conductive sheet 20, thereby further facilitating the control of the thickness of the thermally conductive structure 100.

As can be seen from the foregoing, the sealed cavity 11a is formed by the second heat conductive sheet 20 being hermetically pressed on the first heat conductive sheet 10, so that the plurality of annular capillary grooves 11 form the sealed cavity 11a formed by the hermetic pressing of the second heat conductive sheet 20, and thus the sealed cavity 11a is mainly used for flowing the heat conductive fluid, so as to dissipate heat through the flowing of the heat conductive fluid. It is understood that the heat transfer fluid may be water, ethanol, glycol, methanol, acetone, etc., and the heat transfer fluid may have different boiling points according to the temperature of the object (i.e., the heat generating source 601) to be radiated, and for example, when the heat generating source 601 is a device with high heat generation, such as a chip or a battery, the heat transfer fluid may be water. When the heat source 601 is a device with moderate heat, such as a camera, a flash lamp, or the like, the heat-conducting fluid may be ethanol or ethylene glycol. It is understood that the heat generating source can be, but not limited to, a chip, a battery, a camera, a flash lamp, etc. in an electronic device, which generate heat during operation.

In some embodiments, the sealed cavity 11a may have an evaporation heat absorption region 110, a diffusion region 111, and a condensation heat release region 112. That is, the area of the first heat conductive sheet 10 where the capillary groove 11 is provided may be divided into the evaporation heat absorption area 110, the diffusion area 111, and the condensation heat release area 112. The evaporation heat absorption area 110 may be disposed corresponding to the heat generating source 601, so as to absorb heat emitted from the heat generating source. The diffusion area 111 may be located between the evaporation heat absorption area 110 and the condensation heat release area 112, and the diffusion area 111 is used for diffusing heat of the evaporation heat absorption area 110 to the condensation heat release area 112, so that the heat is condensed by the condensation heat release area 112, thereby achieving a heat dissipation effect. Specifically, as shown in fig. 3, the evaporation heat absorption region 110 is located in a left region of the first heat conductive sheet 10, the diffusion region 111 is located in a middle region of the first heat conductive sheet 10, and the condensation heat release region 112 is located in a right region of the first heat conductive sheet 10, that is, the evaporation heat absorption region 110, the diffusion region 111, and the condensation heat release region 112 are sequentially arranged along a length direction of the first heat conductive sheet 10. By adopting the above manner, the heat absorbed by the evaporation heat absorption region 110 can be quickly diffused to the condensation heat release region 112 by the diffusion region 111 for condensation, so that quick cooling and heat dissipation can be realized, and the heat dissipation effect of the heat conduction structure 100 can be further improved.

It should be understood that the left and right directions are shown as the left and right directions in fig. 3, and the directions are only for convenience of description and do not limit the scope of the present embodiment.

As can be seen from the foregoing, the sealed cavity 11a is mainly formed by the capillary groove 11 formed on the first heat conductive sheet 10 under the sealing and pressing of the second heat conductive sheet 20, and therefore, the evaporation heat absorption region 110, the diffusion region 111 and the condensation heat release region 112 are located at the same height layer on the first heat conductive sheet 10. In other words, after the evaporation heat absorption region 110 absorbs heat of the heat generation source, the heat is directly diffused through the evaporation heat absorption region 110 toward the diffusion region 111, and then diffused through the diffusion region 111 to the condensation heat release region 112. The evaporation heat absorption region 110, the diffusion region 111 and the condensation heat release region 112 are disposed at the same height layer, and compared with the method of disposing the condensation heat release region 112 above the evaporation heat absorption region 110, the heat conduction structure 100 of the present embodiment has a thinner overall thickness, and is suitable for electronic devices with a thinner and lighter design.

In some embodiments, diffusion region 111 is formed as a cavity in the area proximate to evaporative heat absorption region 110. Therefore, the diffusion area can be favorable for rapidly diffusing heat, and the heat is prevented from being gathered at the evaporation heat absorption area, so that the diffusion speed of the heat is improved.

Further, the arrangement density of the capillary grooves 11 located in the diffusion region 111 gradually increases from the position close to the evaporation heat absorption region 110 to the direction away from the evaporation heat absorption region 110, so that the diffusion region 111 is away from the evaporation heat absorption region 110, the arrangement density of the capillary grooves 11 is large, the number of the capillary grooves 11 is large, heat can be cooled, the heat can be rapidly diffused to the condensation heat release region 112, the diffusion speed and the condensation speed of the heat are further improved, and the effects of rapid heat dissipation and temperature reduction are achieved. Specifically, as shown in fig. 3, the arrows with broken lines in fig. 3 indicate the direction of heat diffusion in the capillary grooves 11. The diffusion area 111 is formed as a cavity near the evaporation heat absorption area 110, and the number of the capillary grooves 11 of the diffusion area 111 is increased (i.e. the number of the supporting portions of the first heat conducting sheet 11 is increased) near the condensation heat release area 112, so that heat can be rapidly diffused from the evaporation heat absorption area 110 to the diffusion area 111, and meanwhile, when the diffusion area is near the condensation heat release area 112, the diffusion speed of the heat is reduced, so that the time for the heat to stay in the condensation heat release area 112 can be prolonged, the condensation heat release area 112 can be ensured to condense as much heat as possible, and further, the heat dissipation effect can be ensured.

In addition, the number of the capillary grooves 11 of the diffusion area 111 is increased near the condensation heat release area 112, so that the diffusion area 111 has a certain supporting strength, and the first heat conduction sheet 10 is prevented from collapsing due to insufficient support at the position corresponding to the diffusion area 111.

In some embodiments, the diffusion region 111 has a first diffusion region 111a near the evaporation heat absorption region 110 and a second diffusion region 111b near the condensation heat release region 112, and the width of the second diffusion region 111b is greater than that of the first diffusion region 111 a. Specifically, as shown in fig. 3, the diffusion region 111 is roughly divided into a first diffusion region 111a, a second diffusion region 111b and a transition region 111c located between the first diffusion region 111a and the second diffusion region 111b, the first diffusion region 111a is disposed near the evaporation heat absorption region 110, and is directly communicated with the capillary groove 11 of the evaporation heat absorption region 110, and the first diffusion region 111a is an approximately entire rectangular groove region, that is, the first diffusion region 111a is formed as a cavity. The transition region 111c is also an approximately rectangular region, but in the transition region 111c, the arrangement density of the capillary grooves 11 is greater than that of the first diffusion region 111 a. The second diffusion region 111b is disposed toward the condensation and heat release region 112 and directly connected to the capillary grooves 11 of the condensation and heat release region 112, the second diffusion region 111b is also an approximately rectangular region, and the arrangement density of the capillary grooves 11 of the second diffusion region 111b is greater than that of the capillary grooves 11 of the transition region 111c, so that the second diffusion region 111b has a certain support. Thus, the width b1 of the first diffusion region 111a is less than the width b3 of the transition region 111c, and the width b3 of the transition region 111c is less than the width b2 of the second diffusion region 111 b. This is because the first diffusion region 111a is formed as a cavity which is provided with substantially no support, and if its width is too large, it is liable to cause a collapse condition at the first diffusion region 111a upon vacuum negative pressure pressing. Therefore, when the diffusion region 111 is divided into a plurality of diffusion regions 111, the widths of the plurality of diffusion regions 111 are gradually increased from the direction close to the evaporation heat absorption region 110 to the direction away from the evaporation heat absorption region 110, so that the diffusion region 111 can effectively and rapidly diffuse heat, and the structural strength of the diffusion region 111 can be favorably ensured.

In some embodiments, the width b1 of the first diffusion region 111a is 0.5mm to 5mm, and the width b2 of the second diffusion region 111b is 0.5mm to 5 mm. Illustratively, the width b1 of the first diffusion area 111a may be 0.5mm, 1mm, 2mm, 3mm, 4mm or 5mm, and correspondingly, the width b2 of the second diffusion area 111b may also be 0.5mm, 1mm, 2mm, 3mm, 4mm or 5mm, as long as the width b1 of the first diffusion area 111a is smaller than the width b2 of the second diffusion area 111 b.

In some embodiments, in order to enable the heat of the evaporation heat absorption region 110 to diffuse towards the diffusion region 111 and then diffuse towards the condensation heat release region 112 through the diffusion region 111, in the capillary groove 11 located in the evaporation heat absorption region 110 close to the diffusion region 111 and the capillary groove 11 located in the condensation heat release region 112 close to the diffusion region 111, a groove 113 communicating with two adjacent capillary grooves 11 is provided. Specifically, as shown in fig. 3, the grooves 113 may communicate not only with the adjacent two capillary grooves 11 but also with the diffusion region 111, so that heat may be diffused toward the diffusion region 111 and the condensation heat release region 112 along the communication. By arranging the grooves 113 between two adjacent capillary grooves 11 for communication, the heat-conducting fluid can flow back and forth between the evaporation heat absorption region 110 and the condensation heat release region 112 in a circulating manner, so that the fluid in the condensation heat release region 112 can be effectively ensured to flow back to the evaporation heat absorption region 110 in time for supplement, and the evaporation heat absorption region 110 is prevented from being dried.

As shown in fig. 4, the width b4 of the groove 113 is smaller than the width b5 of the capillary groove 11, so that the capillary groove 11 has a certain capillary force, and the heat-conducting fluid can flow from the groove 113 to the adjacent capillary groove 11, thereby realizing the circulation flow of the heat-conducting fluid.

Illustratively, the width b4 of the groove 113 may be 0.3mm-3mm, such as 0.3mm, 0.8mm, 1mm, 2mm, or 3 mm.

In the heat conducting structure 100 of the present embodiment, the capillary groove 11 is directly formed on the first heat conducting strip 10, and the capillary groove 11 provides a capillary force for flowing the heat conducting fluid, so as to achieve the heat dissipation and cooling effects on the heat source. The heat conduction structure 100 of this embodiment adopts above-mentioned mode, and not only simple structure, effectively simplify manufacturing procedure, need not to carry out accurate counterpoint simultaneously, are favorable to improving this heat conduction structure 100's machining precision and machining efficiency.

In addition, in the heat conducting structure 100 of the first embodiment, the sealed cavity 11a formed by the capillary groove 11 is further divided into the evaporation heat absorption region 110, the diffusion region 111 and the condensation heat release region 112 which are sequentially communicated, so that the evaporation heat absorption region 110, the diffusion region 111 and the condensation heat release region 112 of the heat conducting structure 100 are located at the same height layer, and meanwhile, the diffusion region 111 can be used for rapidly diffusing the heat of the evaporation heat absorption region 110 to the condensation heat release region 112, so that the heat can be condensed as much as possible in the condensation heat release region 112, thereby achieving condensation and heat dissipation effects. Meanwhile, the embodiment optimizes the arrangement density of the capillary grooves 11 in the diffusion region 111 and the widths of different regions of the diffusion region 111 close to the evaporation heat absorption region 110 and the condensation heat release region 112, so as to further achieve the effects of increasing the heat diffusion speed of the hot end (i.e., the evaporation heat absorption region 110) and the condensation speed of the cold end (i.e., the condensation heat release region 112), and further consider the design of the support strength of the first heat conducting sheet 10, thereby avoiding the collapse of the diffusion region 111, and not requiring additional structural support, so that the heat conducting structure 100 can maintain an ultrathin design, and meet the light and thin design requirements of electronic equipment.

Example two

Fig. 5 is a flowchart illustrating a method for manufacturing a heat conducting structure 100 according to a second embodiment of the present disclosure. The preparation method can comprise the following steps:

501. providing a first heat conducting sheet, and forming a plurality of capillary grooves on the first heat conducting sheet.

In this step, the capillary groove 11 formed on the first heat conducting sheet 10 may be formed by micro etching, so that the depth and the width of the formed capillary groove 11 are both small, and the effect that the capillary groove 11 can provide capillary force is achieved.

Optionally, the first heat conducting strip 10 may be a metal sheet, such as a copper sheet or a stainless steel sheet, so that the first heat conducting strip 10 has sufficient structural strength on one hand, and the copper sheet or the stainless steel sheet has good heat conducting performance on the other hand, and can conduct heat emitted by a heat source when connected with the heat source of the electronic device.

Alternatively, the first thermally conductive sheet 10 may be a long sheet shape to have a sufficient area to be connected to the heat generating source. In actual connection, the first heat conducting sheet 10 is usually directly attached to the heat source, and the first heat conducting sheet 10 covers the heat source as completely as possible, so that the first heat conducting sheet 10 has a sufficient heat conducting area to conduct heat emitted by the heat source, and on the other hand, the heat emitted by the heat source is prevented from being diffused to other components of the electronic device.

Alternatively, the cross-sectional shape of the capillary groove 11 may be circular, elliptical, or polygonal. Specifically, when the cross section of the capillary groove 11 is polygonal, it may be an inverted triangle, an inverted trapezoid, a rectangle, a square, or other polygons, such as a hexagon, an octagon, and the like. The capillary groove 11 has a circular, elliptical or polygonal cross section, which facilitates the processing of the capillary groove 11, thereby simplifying the processing technique of the heat conducting structure 100 and reducing the processing difficulty.

Alternatively, each capillary groove 11 may be provided on the first heat conductive sheet 10 in a ring shape along the outer shape of the first heat conductive sheet 10. For example, referring to fig. 3, a plurality of capillary grooves 11 are formed in the first heat conducting sheet 10 (the filled portions in fig. 3 indicate portions of the first heat conducting sheet 10 where no capillary groove 11 is formed, the portions can be press-fit connected with the second heat conducting sheet 20, and serve as support portions, and the blank portions between two adjacent filled portions indicate capillary grooves 11), the plurality of capillary grooves 11 are all annular grooves, each capillary groove 11 is circumferentially formed along the outer shape of the first heat conducting sheet 10, and each capillary groove 11 is sequentially arranged along the center of the first heat conducting sheet 10 at intervals outward, so that the first heat conducting sheet 10 still has sufficient support to be press-fit connected with the second heat conducting sheet 20, and the first heat conducting sheet 10 is prevented from being concave when the vacuum negative pressure occurs due to insufficient support. In addition, with the above arrangement, it is not necessary to additionally provide a support structure on the first thermally conductive sheet 10 to support the second thermally conductive sheet 20, thereby further facilitating the control of the thickness of the thermally conductive structure 100.

502. And the second heat conducting fin is connected to the first heat conducting fin in a sealing manner, so that a plurality of capillary grooves on the first heat conducting fin form a sealed cavity for the circulation of heat conducting fluid between the first heat conducting fin and the second heat conducting fin.

Specifically, in the actual preparation, the second thermally conductive sheet 20 is connected to the first thermally conductive sheet 10 in a sealing manner by pressing, filling and sealing, so as to ensure that the second thermally conductive sheet 20 and the first thermally conductive sheet 10 are completely sealed, and a vacuum negative pressure environment can be formed inside the sealed cavity 11a, so as to facilitate the circulation of the thermally conductive fluid.

In some embodiments, the sealed cavity 11a may have an evaporation heat absorption region 110, a diffusion region 111, and a condensation heat release region 112. That is, the area of the first heat conductive sheet 10 where the capillary groove 11 is provided may be divided into the evaporation heat absorption area 110, the diffusion area 111, and the condensation heat release area 112. The evaporation heat absorption area 110 may be disposed corresponding to the heat source, so as to absorb heat emitted from the heat source. The diffusion area 111 may be located between the evaporation heat absorption area 110 and the condensation heat release area 112, and the diffusion area 111 is used for diffusing heat of the evaporation heat absorption area 110 to the condensation heat release area 112, so that the heat is condensed by the condensation heat release area 112, thereby achieving a heat dissipation effect. Specifically, as shown in fig. 3, the evaporation heat absorption region 110 is located in a left region of the first heat conductive sheet 10, the diffusion region 111 is located in a middle region of the first heat conductive sheet 10, and the condensation heat release region 112 is located in a right region of the first heat conductive sheet 10, that is, the evaporation heat absorption region 110, the diffusion region 111, and the condensation heat release region 112 are sequentially arranged along a length direction of the first heat conductive sheet 10. By adopting the above manner, the heat absorbed by the evaporation heat absorption region 110 can be quickly diffused to the condensation heat release region 112 by the diffusion region 111 for condensation, so that quick cooling and heat dissipation can be realized, and the heat dissipation effect of the heat conduction structure 100 can be further improved.

As can be seen from the foregoing, the sealed cavity 11a is mainly formed by the capillary groove 11 formed on the first heat conductive sheet 10 under the sealing and pressing of the second heat conductive sheet 20, and therefore, the evaporation heat absorption region 110, the diffusion region 111 and the condensation heat release region 112 are located on the same layer on the first heat conductive sheet 10. In other words, after the evaporation heat absorption region 110 absorbs heat of the heat generation source, the heat is directly diffused through the evaporation heat absorption region 110 toward the diffusion region 111, and then diffused through the diffusion region 111 to the condensation heat release region 112. The evaporation heat absorption region 110, the diffusion region 111 and the condensation heat release region 112 are disposed at the same height layer, and compared to the related art in which the condensation heat release region 112 is disposed above the evaporation heat absorption region 110, the heat conduction structure 100 of the present embodiment has a thinner overall thickness, and is suitable for electronic devices with a thinner and lighter design.

Further, the arrangement density of the capillary grooves 11 located in the diffusion region 111 gradually increases from the position close to the evaporation heat absorption region 110 to the direction away from the evaporation heat absorption region 110, so that the diffusion region 111 is away from the evaporation heat absorption region 110, the arrangement density of the capillary grooves 11 is large, the number of the capillary grooves 11 is large, heat can be cooled, the heat can be rapidly diffused to the condensation heat release region 112, the diffusion speed and the condensation speed of the heat are further improved, and the effects of rapid heat dissipation and temperature reduction are achieved. Specifically, as shown in fig. 3, the arrows with broken lines in fig. 3 indicate the direction of heat diffusion in the capillary grooves 11. The diffusion area 111 is formed as a cavity near the evaporation heat absorption area 110, and the number of capillary grooves 11 of the diffusion area 111 is increased near the condensation heat release area 112 (i.e. the number of the supporting portions of the first heat conducting sheet 11 is increased, since the capillary grooves are formed between two adjacent supporting portions), so that heat can be rapidly diffused from the evaporation heat absorption area 110 to the diffusion area 111, and meanwhile, when the capillary grooves are near the condensation heat release area 112, the diffusion speed of the heat is reduced, so that the time for the heat to stay in the condensation heat release area 112 can be prolonged, the condensation heat release area 112 can condense as much heat as possible, and further the heat dissipation effect can be ensured.

In some embodiments, the diffusion region 111 has a first diffusion region 111a near the evaporation heat absorption region 110 and a second diffusion region 111b near the condensation heat release region 112, and the width b2 of the second diffusion region 111b is greater than the width b1 of the first diffusion region 111 a. Specifically, as shown in fig. 3, the diffusion region 111 is roughly divided into a first diffusion region 111a, a second diffusion region 111b and a transition region 111c located between the first diffusion region 111a and the second diffusion region 111b, the first diffusion region 111a is disposed near the evaporation heat absorption region 110, and is directly communicated with the capillary groove 11 of the evaporation heat absorption region 110, and the first diffusion region 111a is an approximately entire rectangular groove region, that is, the first diffusion region 111a is formed as a cavity. The transition region 111c is also an approximately rectangular region, but in the transition region 111c, the arrangement density of the capillary grooves 11 is greater than that of the first diffusion region 111 a. The second diffusion region 111b is disposed toward the condensation and heat release region 112 and directly connected to the capillary grooves 11 of the condensation and heat release region 112, the second diffusion region 111b is also an approximately rectangular region, and the arrangement density of the capillary grooves 11 of the second diffusion region 111b is greater than that of the capillary grooves 11 of the transition region 111c, so that the second diffusion region 111b has a certain support. Thus, the width b1 of the first diffusion region 111a is less than the width b3 of the transition region 111c, and the width b3 of the transition region 111c is less than the width b2 of the second diffusion region 111 b. This is because the first diffusion region 111a is provided with substantially no support, and if its width is too large, it is liable to cause a collapse condition at the first diffusion region 111a at the time of vacuum negative pressure pressing. Therefore, when the diffusion region 111 is divided into a plurality of diffusion regions 111, the widths of the plurality of diffusion regions 111 are gradually increased from the direction close to the evaporation heat absorption region 110 to the direction away from the evaporation heat absorption region 110, so that the diffusion region 111 can effectively and rapidly diffuse heat, and the structural strength of the diffusion region 111 can be favorably ensured.

In the manufacturing method of the heat conducting structure 100 disclosed in the second embodiment of the present invention, the capillary groove 11 is directly formed on the first heat conducting strip 10, so that the capillary groove 11 can provide a capillary force to facilitate the circulation of the heat conducting fluid, and therefore, the heat conducting structure 100 of the second embodiment does not need to additionally add fibers or weave copper mesh, which not only simplifies the manufacturing process of the heat conducting structure 100, but also is beneficial to reduce the overall thickness of the heat conducting structure 100, so as to meet the design requirement of lightness and thinness.

In addition, the embodiment further divides the sealed cavity 11a formed by the capillary groove 11 into the evaporation heat absorption region 110, the diffusion region 111 and the condensation heat release region 112, and the heat can be rapidly diffused from the evaporation heat absorption region 110 to the condensation heat release region 112 by using the way that the diffusion region 111 is communicated with the evaporation heat absorption region 110 and the condensation heat release region 112, so that the heat is prevented from being concentrated in the evaporation heat absorption region 110, and the heat dissipation effect of the heat conduction structure 100 is effectively improved. Meanwhile, in the present embodiment, the arrangement density of the capillary grooves 11 in the diffusion region 111 and the widths of different regions of the diffusion region 111 close to the evaporation heat absorption region 110 and the condensation heat release region 112 are further optimized, so that the structural strength of the heat conducting structure 100 can be further considered under the condition that the heat dissipation effect is considered, and no additional support structure is required to be arranged, so that the heat conducting structure 100 realizes an ultra-thin design.

EXAMPLE III

Please refer to fig. 6, which is a schematic structural diagram of an electronic device disclosed in the third embodiment of the present application. The electronic device 600 of the present application includes the heat generating source 601 and the heat conducting structure 100 as described in the first embodiment above. The heat conducting structure 100 is connected to the heat generating source 601. In particular, the electronic device 600 may include, but is not limited to, a smart phone, a smart watch, a tablet computer, a handheld game console, and the like. The heat generating source 601 may be an electronic device in the electronic apparatus 600 that emits heat during operation, and may illustratively be a battery, a chip (or a motherboard), a camera, a flash, a speaker, or the like.

In actual installation, because the heat source 601 is located inside the electronic device 600, and corresponding to the heat source, the heat conducting structure 100 is also located inside the electronic device 600, and the heat conducting structure 100 can be directly attached to the heat source 601 and connected to the heat source 601, so that heat can be conducted to the heat conducting structure 100 as much as possible for condensation, and further heat dissipation and cooling effects can be achieved.

The electronic device 600 disclosed in the third embodiment of the application performs heat treatment on the heating source 601 by setting the heat conducting structure 100, and can achieve the effects of rapid heat dissipation and cooling. In addition, since the overall thickness of the heat conducting structure 100 is very small, the heat conducting structure is disposed in the electronic device 600, and the space occupied by the electronic device 600 is small, so that the heat conducting structure 100 can be applied to the electronic device 600 with high requirements for light weight and thin design, and has a wide application range.

The heat conducting structure, the preparation method thereof, and the electronic device disclosed in the embodiments of the present invention are described in detail above, and the principle and the embodiment of the present invention are explained in detail herein by applying specific examples, and the description of the embodiments above is only used to help understanding the heat conducting structure, the preparation method thereof, the electronic device, and the core concept thereof; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.

Claims

1. A heat conducting structure is characterized by comprising

The heat sink comprises a first heat conducting sheet, a second heat conducting sheet and a heat conducting layer, wherein a plurality of capillary grooves are formed in the first heat conducting sheet; and

2. The structure of claim 1, wherein the diffusion region is formed as a cavity in a region near the evaporation heat absorption region.

3. The structure of claim 1, wherein the capillary grooves in the diffusion region are arranged at a density gradually increasing from the position near the evaporation heat absorption region to the position far away from the evaporation heat absorption region.

4. The structure of claim 3, wherein the diffusion region has a first diffusion region adjacent the evaporative heat absorption region and a second diffusion region adjacent the condensation heat release region, the second diffusion region having a width greater than the width of the first diffusion region.

5. The heat transfer structure of claim 4, wherein the first diffusion region has a width of 0.5mm to 5mm, and the second diffusion region has a width of 0.5mm to 5 mm.

6. The heat transfer structure of any one of claims 1 to 5, wherein the first heat transfer sheet is an elongated sheet, and the evaporation heat absorption region, the diffusion region, and the condensation heat release region are sequentially arranged along a length direction of the first heat transfer sheet.

7. The structure according to any one of claims 1 to 5, wherein a groove communicating with each other is provided between the capillary grooves located in the evaporation heat absorption region near the diffusion region and the capillary grooves located in the condensation heat release region near the diffusion region.

8. The heat transfer structure of any one of claims 1 to 5, wherein the depth of the capillary groove is greater than or equal to the width of the capillary groove.

9. The heat transfer structure of claim 8, wherein the capillary groove has a depth of 30-200 μm and a width of 20-200 μm.

10. The heat transfer structure of any one of claims 1 to 5, wherein the capillary grooves have a cross-sectional shape of an inverted triangle, an inverted trapezoid, a rectangle, a square, a circle, or an ellipse.

11. A method of making a thermally conductive structure, the method comprising:

the sealed cavity is provided with an evaporation heat absorption area, a diffusion area and a condensation heat release area, the evaporation heat absorption area is arranged corresponding to the heating source to absorb heat emitted by the heating source, the diffusion area is located between the evaporation heat absorption area and the condensation heat release area, and the diffusion area is used for diffusing the heat of the evaporation heat absorption area to the condensation heat release area.

12. The method of claim 11, wherein the capillary groove is formed on the first heat-conducting sheet using a micro-etching process.

13. An electronic device, comprising a heat-generating source and the heat-conducting structure of any one of claims 1-10, wherein the heat-conducting structure is connected to the heat-generating source to dissipate heat from the heat-generating source.