Ultrathin vapor chamber

Abstract

The utility model relates to the technical field of vapor chambers, and provides an ultrathin vapor chamber. The ultrathin vapor chamber comprises a lower shell plate; the lower shell plate and the upper shell plate are connected with each other to form a sealed cavity; the sealing cavity is used for accommodating a cooling working medium; the capillary layer is located between the upper shell plate and the lower shell plate, and a plurality of capillary protrusions abutting against the lower shell plate are arranged on the capillary layer; a cooling working medium flows in the capillary layer through the capillary protrusions. According to the ultrathin vapor chamber, the capillary layer and the capillary protrusions in the closed cavity can transmit a liquid cooling working medium to the heat absorption end where heat is concentrated for heat absorption, and a gas channel can also be formed to transmit a gas cooling working medium to the condensation end for heat dissipation, so that heat transfer and transfer are achieved; gas-liquid coplane of a cooling working medium is achieved, thermal resistance can be reduced, heat transfer efficiency is improved, and the overall thickness is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of vapor chambers, and in particular to an ultra-thin vapor chamber. Background Art

[0002] With the rapid development of technology, electronic components tend to be miniaturized, high-powered, and highly integrated; therefore, the heat dissipation requirements of electronic components increase.

[0003] Heat spreaders are usually used for electronic products that require a small volume or need to quickly dissipate high heat, such as servers, high-end graphics cards and other products. The flat heat spreader can fit the chip well, so that it can better dissipate the heat of the chip with high heat flux density. The flat heat spreader is filled with a certain amount of cooling medium (such as deionized water). Its working principle is that heat is absorbed from one end, the temperature of the cooling medium inside the cavity increases, and the liquid cooling medium evaporates into a gas, carrying the heat to the other end, and finally dissipating it. At this time, the gaseous cooling medium condenses into liquid, flows back from the built-in capillary device to the heat absorption end, and circulates back and forth. The main features of the flat heat spreader are two-dimensional heat transfer, high efficiency, and high equivalent thermal conductivity.

[0004] Most existing vapor chambers are relatively thick, typically 3-5mm thick, which cannot meet the growing trend of thinner and more compact electronic products. Ordinary heat pipes conduct heat in one dimension, so their efficiency decreases after being flattened, and they cannot meet the needs of high heat flux density electronic products. In addition, the gas and liquid in existing thin vapor chambers are not coplanar, resulting in a large thermal resistance problem.

[0005] Therefore, the existing heat spreader has the problems of being relatively thick, having a high thermal conductivity and a relatively large thermal resistance. Utility Model Content

[0006] In view of the above-mentioned deficiencies in the prior art, the purpose of this application is to provide an ultra-thin heat spreader and terminal device, aiming to solve the problems of the existing heat spreader being thick, having high thermal conductivity and large thermal resistance.

[0007] The technical solution adopted by the present application to solve the technical problem is as follows: an ultra-thin heat spreader is provided, comprising: a lower shell plate; an upper shell plate, the upper shell plate and the lower shell plate are interconnected to form a sealed cavity; the sealed cavity is used to accommodate a cooling medium; a capillary layer, the capillary layer is located between the upper shell plate and the lower shell plate, and the capillary layer is provided with a plurality of capillary protrusions abutting the lower shell plate; the cooling medium flows in the capillary layer through the plurality of capillary protrusions.

[0008] Optionally, the capillary layer includes a capillary bottom layer, and a plurality of the capillary protrusions are distributed in parallel on the capillary bottom layer; the cross-sectional area of ​​the capillary protrusions accounts for greater than or equal to 30% of the cross-sectional area of ​​the sealed cavity.

[0009] Optionally, the thickness ratio of the capillary bottom layer to the capillary protrusions is 1:(5-20).

[0010] Optionally, the lower shell plate is provided with a plurality of supporting protrusions for supporting the upper shell plate.

[0011] Optionally, the supporting protrusion is located between adjacent capillary protrusions, and there is a gap between the supporting protrusion and the adjacent capillary protrusions.

[0012] Optionally, between adjacent capillary protrusions, the ratio of the width of the gap to the width of the supporting protrusion is (0.5-2):1.

[0013] Optionally, a lower groove is provided on the lower shell plate; the sealed cavity is communicated with the lower groove; an upper groove is provided on the upper shell plate, and the upper groove and the lower groove are interconnected to form a liquid-filled cavity for introducing a cooling medium.

[0014] Optionally, the ultra-thin vapor chamber further includes a liquid filling tube, and the liquid filling tube is arranged corresponding to the liquid filling cavity.

[0015] Optionally, the upper shell plate and the lower shell plate are sealed and connected by diffusion welding.

[0016] Optionally, the thickness of the ultra-thin heat spreader is less than or equal to 2 mm; the upper shell plate is a copper shell plate with a thickness of 0.03-008 mm; and the lower shell plate is a copper shell plate with a thickness of 0.03-008 mm.

[0017] Compared with the prior art, the present application provides an ultra-thin heat spreader including a lower shell plate, an upper shell plate and a capillary layer. The lower shell plate and the upper shell plate are connected to form a closed cavity for placing the capillary layer and accommodating the cooling medium. The capillary layer is provided with capillary protrusions abutting the lower shell plate, which can transfer the liquid cooling medium to the heat-concentrated heat-absorbing end for heat absorption, and can also form a gas channel to transfer the gaseous cooling medium to the condensation end for heat dissipation, thereby realizing heat transfer and transfer; and the cooling medium on the capillary layer can be coplanar, which can reduce thermal resistance, improve heat transfer efficiency, and at the same time reduce the thickness of the ultra-thin heat spreader, which is suitable for electronic products that need to dissipate high heat quickly. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a disassembled diagram of the ultra-thin vapor chamber provided in this application;

[0019] Figure 2 This is a front view of the ultra-thin vapor chamber (excluding the upper shell) provided in this application;

[0020] Figure 3 This application Figure 2An enlarged schematic diagram of the AA section;

[0021] Figure 4 is a schematic diagram of the capillary layer in this application;

[0022] Figure 5 This application Figure 4 Schematic diagram of the enlarged BB cross section.

[0023] Description of reference numerals:

[0024] 1. Liquid filling tube; 2. Upper shell plate; 21. Upper extension section; 211. Upper groove; 3. Capillary layer; 31. Capillary protrusion; 32. Capillary bottom layer; 4. Lower shell plate; 41. Support protrusion; 42. Lower extension section; 421. Lower groove. DETAILED DESCRIPTION

[0025] The following describes in detail embodiments of the present application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application and are not to be construed as limiting the present application.

[0026] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0027] In the description of this application, it should be noted that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to direct connections or indirect connections through an intermediary. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0028] Combined with reference Figure 1 、 Figure 2 and Figure 3In the first embodiment of the present application, an ultra-thin heat spreader is provided, comprising: a lower shell plate 4; an upper shell plate 2, wherein the lower shell plate 4 and the upper shell plate 2 are interconnected to form a sealed cavity; the sealed cavity is used to accommodate a cooling medium; a capillary layer 3, wherein the capillary layer 3 is located between the upper shell plate 2 and the lower shell plate 4, and a plurality of capillary protrusions 31 abutting against the lower shell plate 4 are provided on the capillary layer 3; the cooling medium flows in the capillary layer 3 through the capillary protrusions 31.

[0029] The edges of the upper shell plate 2 and the lower shell plate 4 can be provided with corresponding protrusions so that a sealed cavity can be formed after connection; the connection method can be welding connection, which reduces costs and improves the connection stability. The sealed cavity is used to accommodate the cooling medium, facilitating the two-phase conversion of the cooling medium into gaseous and liquid states, thereby improving the heat transfer efficiency of the ultra-thin heat spreader. The presence of the capillary structure in the capillary layer 3 provides a gas channel and a liquid channel for the cooling medium. Specifically, the capillary force of the capillary layer 3 can attract the liquid cooling medium to flow back. At the same time, the porous structure of the capillary layer 3 also provides the necessary space for the cooling medium to evaporate, which helps the overflow and flow of the gaseous cooling medium.

[0030] Capillary protrusions 31 are provided on the capillary layer 3 to facilitate the movement of the cooling medium through the capillary protrusions 31 within the capillary layer 3, thereby reaching a position abutting the lower shell plate 4 for heat transfer. The capillary layer 3 preferably conforms to the upper shell plate 2, allowing the cooling medium to move from a position abutting the lower shell plate 4 to a position close to the upper shell plate 2, which is beneficial for the cooling medium to transfer heat between the lower shell plate 4 and the upper shell plate 2.

[0031] The ultra-thin heat spreader of this embodiment includes a lower shell plate 4, an upper shell plate 2 and a capillary layer 3. The lower shell plate 4 and the upper shell plate 2 are connected to form a closed cavity for placing the capillary layer 3 and accommodating the cooling medium. The capillary layer 3 is provided with a capillary protrusion 31 abutting the lower shell plate 4, which can transfer the liquid cooling medium to the heat absorption end where heat is concentrated for heat absorption, and can also form a gas channel to transfer the gaseous cooling medium to the condensation end for heat dissipation, thereby realizing heat transfer and transfer; and the cooling medium on the capillary layer 3 can be coplanar, which can reduce thermal resistance, improve heat transfer efficiency, and at the same time reduce the thickness of the ultra-thin heat spreader, which is suitable for electronic products that need to quickly dissipate high heat.

[0032] Combined with reference Figure 4 and Figure 5 In some embodiments, the capillary layer 3 includes a capillary bottom layer 32, and a plurality of capillary protrusions 31 are distributed in parallel on the capillary bottom layer 32; the cross-sectional area of ​​the capillary protrusions 31 accounts for greater than or equal to 30% of the cross-sectional area of ​​the sealed cavity.

[0033] The capillary protrusions 31 are arranged in parallel, with gaps between adjacent capillary protrusions 31. This provides a gas channel for the gaseous coolant, facilitating a gas-liquid coplanar state in the capillary base layer 32, thus facilitating heat transfer. Furthermore, the increased cross-sectional area of ​​the capillary protrusions 31 increases the contact area between the capillary layer 3 and the lower shell plate 4, facilitating heat transfer to the lower shell plate 4. The porosity of the capillary base layer 32 and the capillary protrusions 31 of the capillary layer 3 is generally greater than 80% to provide sufficient capillary force.

[0034] Furthermore, the cross-sectional area of ​​the capillary protrusions 31 increases as they approach the lower shell plate 4, further increasing the contact area between the capillary layer 3 and the lower shell plate 4 and, in turn, the capillary force. Furthermore, the spacing between adjacent capillary protrusions 31 allows for the insertion of the support protrusions 41 to provide sufficient support force; that is, the spacing between adjacent capillary protrusions 31 is greater than or equal to the width of the support protrusions 41. The spacing between adjacent capillary protrusions 31 is preferably (1-2) times the width of a single support protrusion 41. After a support protrusion 41 is inserted, a certain gap remains for gas passage.

[0035] In some embodiments, the lower shell plate 4 is provided with a plurality of support protrusions 41 for supporting the upper shell plate 2. The support protrusions 41 are used to support the upper shell plate 2 to prevent the ultra-thin heat spreader as a whole from collapsing or breaking when subjected to high pressure; that is, the support protrusions 41 support the sealed cavity formed by the upper shell plate 2 and the lower shell plate 4 to prevent the sealed cavity from collapsing, causing the cooling medium to flow out and reducing the heat transfer efficiency of the ultra-thin heat spreader.

[0036] In some embodiments, the support protrusions 41 are located between adjacent capillary protrusions 31, with a gap between the support protrusions 41 and the adjacent capillary protrusions 31. This gap ensures that the support protrusions 41 support the sealed cavity and the contact area between the capillary layer 3 and the lower shell 4 is maintained. It also provides a certain amount of space for accommodating liquid cooling medium or a certain amount of buffer space for phase change of the cooling medium, thereby preventing deformation of the sealed cavity caused by thermal expansion and contraction of the ultra-thin heat spreader, which in turn affects the heat transfer efficiency.

[0037] The sum of the thickness of the capillary protrusion 31 at the center of the capillary layer 3 and the thickness of the capillary layer 3 is preferably equal to the distance between the upper shell plate 2 and the lower shell plate 4, that is, the capillary protrusion 31 at the center of the capillary layer 3 plays a supporting role. The thickness of the capillary protrusions 31 on the other two sides can be the same as the thickness of the capillary protrusion 31 at the center of the capillary layer 3, playing a supporting role, or can be less than the thickness of the capillary protrusion 31 at the center of the capillary layer 3. Specifically, the height arrangement of the capillary protrusion 31 and the capillary bottom layers 32 on both sides of the capillary protrusion 31 can reduce the thermal resistance of the capillary structure and improve heat transfer efficiency while achieving coplanarity between the cooling medium gas and liquid.

[0038] The cross section of the support protrusion 41 can be a regular shape such as a rectangle, a square, a trapezoid, a circle, or an irregular shape, and is preferably a circle for facilitating etching.

[0039] In some embodiments, the ratio of the width of the gap between adjacent capillary protrusions 31 to the width of the support protrusion 41 is (0.5-2):1. This improves the stability of the ultra-thin vapor chamber while ensuring the heat transfer efficiency of the working fluid in the sealed cavity.

[0040] In some embodiments, the ratio of the thickness of the capillary bottom layer 32 to the capillary protrusion 31 is 1:(5-20). The capillary protrusion 31 provides sufficient capillary force to attract and return the liquid cooling medium, and promotes the movement of the liquid cooling medium in the sealed cavity, thereby improving the gas-liquid circulation efficiency and the heat transfer performance of the ultra-thin vapor chamber.

[0041] In some embodiments, the lower shell plate 4 is provided with a lower groove 421; the sealed cavity is in communication with the lower groove 421. The provision of the lower groove 421 can provide a channel for the filling of the cooling medium into the sealed cavity, and a channel for vacuum extraction, so that the sealed cavity is a vacuum cavity, preventing external gas from affecting the cooling medium.

[0042] Further, the upper shell plate 2 is provided with an upper groove 211, which is connected to the lower groove 421 to form a liquid filling chamber for introducing the cooling medium. The liquid filling chamber provides a channel for the introduction of the cooling medium.

[0043] The upper groove 211 can be directly in communication with the sealed cavity, or in communication with the sealed cavity through the lower groove 421; specifically, the communication ports of the upper groove 211 and the sealed cavity and the communication ports of the lower groove 421 and the sealed cavity are small and located inside the upper shell plate 2 and the lower shell plate 4, respectively, and can be sealed after the cooling medium is introduced, without affecting the structure of the sealed cavity and the capillary layer 3, and without affecting the heat transfer efficiency of the ultra-thin vapor chamber.

[0044] In some embodiments, the lower shell plate 4 extends outward on one side to form a lower elongated section 42, and the lower groove 421 is located on the lower elongated section 42; the upper shell plate 2 extends outward on one side to form an upper elongated section 21 corresponding to the lower elongated section 42, and the upper groove 211 is located on the upper elongated section 21, which is connected through the upper elongated section 21 and the lower elongated section to form a liquid guide chamber, thereby simplifying the preparation and production process of the ultra-thin vapor chamber without affecting the structure of the sealed cavity of the ultra-thin vapor chamber.

[0045] In some embodiments, the ultra-thin vapor chamber further comprises a liquid filling pipe 1, which is correspondingly arranged with the liquid filling chamber. The liquid filling pipe 1 can be used to fill the cooling medium into the liquid filling chamber, and then into the sealed cavity; the liquid filling pipe 1 can also be used for vacuum extraction.

[0046] In some embodiments, the upper shell 2 and the lower shell 4 are hermetically connected by diffusion welding. Diffusion welding the upper shell 2 to the lower shell 4 provides support for the capillary layer 3, preventing collapse of the upper and lower shells 2 and 4, and significantly reducing the size of the ultra-thin vapor chamber.

[0047] In some embodiments, the thickness of the ultra-thin heat spreader is less than or equal to 2 mm; the upper shell plate 2 is a copper shell plate with a thickness of 0.03-0.08 mm; and the lower shell plate 4 is a copper shell plate with a thickness of 0.03-0.08 mm. Both the upper shell plate 2 and the lower shell plate 4 can be formed through extrusion and etching processes to reduce costs. Furthermore, the thickness setting provides a certain degree of support for the upper shell plate 2 and the lower shell plate 4, and the resulting ultra-thin heat spreader is thin and compact. The support protrusions 41 on the lower shell plate 4 can be etched from oxygen-free copper, which has a higher thermal conductivity than aluminum and stainless steel, while resisting corrosion from the cooling medium.

[0048] In addition, the capillary layer 3 and the capillary protrusions 31 provided on the capillary layer 3 can be formed by placing copper powder into a mold and sintering it.

[0049] The present application provides a method for preparing an ultra-thin vapor chamber, comprising the following steps.

[0050] Step 1: The upper shell plate 2 is obtained by copper stamping and then cleaned for standby use. An upper groove 211 is left in the upper shell plate 2.

[0051] Step 2: The lower shell plate 4 is obtained by copper stamping and then cleaned for use. The support protrusion 41 is etched on the lower shell plate 4 by oxygen-free copper, and a lower groove 421 is left in the lower shell plate 4.

[0052] Step three: Place copper powder into a mold of the capillary layer 3 and sinter it to obtain a capillary layer 3 having capillary protrusions 31 for later use.

[0053] Step 4: Place the capillary layer 3 with capillary protrusions 31 between the lower shell plate 4 and the upper shell plate 2, with the upper groove 211 corresponding to the lower groove 421, and form them into one piece through diffusion welding to obtain a prototype of an ultra-thin heat spreader with a sealed cavity and a liquid-filled cavity.

[0054] Step 5: Check the prototype for leaks. If no leaks occur, fill the liquid-filled cavity with a coolant, evacuate the cavity, and seal the cavity entrance to obtain the ultra-thin vapor chamber. Laser welding can be used to seal the cavity entrance.

[0055] The ultra-thin vapor chamber of the first embodiment and its implementation methods can be prepared according to the above preparation method. The overall preparation method is simple, low-cost, and can meet the needs of large-scale production.

[0056] In summary, the present application provides an ultra-thin heat spreader, comprising a lower shell plate, an upper shell plate and a capillary layer. The lower shell plate and the upper shell plate are connected to form a closed cavity for placing the capillary layer and accommodating the cooling medium. The capillary layer is provided with capillary protrusions abutting the lower shell plate, which can transfer the liquid cooling medium to the heat-concentrated heat-absorbing end for heat absorption, and can also form a gas channel to transfer the gaseous cooling medium to the condensation end for heat dissipation, thereby realizing heat transfer and transfer; and the cooling medium on the capillary layer can be coplanar, which can reduce thermal resistance, improve heat transfer efficiency, and at the same time reduce the thickness of the ultra-thin heat spreader, which is suitable for electronic products that need to dissipate high heat quickly.

[0057] Finally, it should be noted that the above examples are only used to illustrate the technical solutions of the present application, and not to limit them. Although the present application has been described in detail with reference to the above examples, ordinary technicians in this field should understand that they can still modify the technical solutions recorded in the above examples, or make equivalent replacements for some of the technical features therein. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the examples in the present application.

Claims

1. An ultra-thin vapor chamber, characterized in that: include: lower shell plate; an upper shell plate, wherein the upper shell plate and the lower shell plate are connected to each other to form a sealed cavity; The sealed cavity is used to accommodate the cooling medium; a capillary layer, the capillary layer being located between the upper shell plate and the lower shell plate, and being provided with a plurality of capillary protrusions abutting against the lower shell plate; The cooling medium flows in the capillary layer through a plurality of the capillary protrusions.

2. The ultra-thin vapor chamber according to claim 1, wherein: The capillary layer includes a capillary bottom layer, and a plurality of capillary protrusions are distributed in parallel on the capillary bottom layer; the cross-sectional area of ​​the capillary protrusions accounts for more than or equal to 30% of the cross-sectional area of ​​the sealed cavity.

3. The ultra-thin vapor chamber according to claim 2, wherein: The thickness ratio of the capillary bottom layer to the capillary protrusions is 1:(5-20).

4. The ultra-thin vapor chamber according to claim 1, wherein: The lower shell plate is provided with a plurality of supporting protrusions for supporting the upper shell plate.

5. The ultra-thin vapor chamber according to claim 4, characterized in that: The supporting protrusion is located between adjacent capillary protrusions, and a gap exists between the supporting protrusion and the adjacent capillary protrusions.

6. The ultra-thin vapor chamber according to claim 5, characterized in that: Between adjacent capillary protrusions, the ratio of the width of the gap to the width of the supporting protrusion is (0.5-2):

1.

7. The ultra-thin vapor chamber according to claim 6, wherein: The lower shell plate is provided with a lower groove; the sealed cavity is communicated with the lower groove; the upper shell plate is provided with an upper groove, and the upper groove and the lower groove are connected to each other to form a liquid-filled cavity for introducing a cooling medium.

8. The ultra-thin vapor chamber according to claim 7, wherein: The ultra-thin heat spreader further includes a liquid filling tube, which is arranged corresponding to the liquid filling cavity.

9. The ultra-thin vapor chamber according to claim 1, wherein: The upper shell plate and the lower shell plate are sealed and connected by diffusion welding.

10. The ultra-thin vapor chamber according to claim 1, wherein: The thickness of the ultra-thin heat spreader is less than or equal to 2 mm; the upper shell plate is a copper shell plate with a thickness of 0.03-008 mm; the lower shell plate is a copper shell plate with a thickness of 0.03-008 mm.

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