Heat dissipation cover, chip packaging structure and forming method thereof

Abstract

The invention relates to a heat dissipation cover, a chip packaging structure and a forming method thereof. The heat dissipation cover comprises a supporting shell, the supporting shell comprises a top surface and a bottom surface which are oppositely distributed, the bottom surface is used for covering a chip, the area of the top surface of the supporting shell is larger than that of the bottom surface of the supporting shell, and a vacuum containing cavity is formed in the supporting shell; the first partition plates are located between the top face of the supporting shell and the bottom face of the supporting shell, the multiple first partition plates are arranged at intervals and divide the vacuum containing cavity into a middle heat dissipation cavity and a peripheral heat dissipation cavity which are independent of each other, and the middle heat dissipation cavity is located in the middle of the vacuum containing cavity; the peripheral heat dissipation cavities are distributed around the periphery of the middle heat dissipation cavity; and the cooling liquid is positioned in the middle heat dissipation cavity and the peripheral heat dissipation cavity. According to the invention, the heat dissipation effect of the chip is improved, and meanwhile, the manufacturing difficulty and the manufacturing cost of the heat dissipation cover are greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor manufacturing, and particularly to a heat dissipation cover, a chip packaging structure and a method for forming the same. Background Art

[0002] As the integration degree of the packaging structure continues to increase and the frequency continues to rise, the heat dissipation of the packaging structure has become increasingly prominent. The accumulation of heat inside the packaging structure will cause the temperature of electronic structures such as functional chips and functional devices in the packaging structure to be too high, thereby affecting the performance of the electronic structures such as the functional chips and functional devices, and easily shortening the service life of the packaging structure.

[0003] At present, the main method to improve the heat dissipation performance of the packaging structure is to reduce the thermal resistance, and there are mainly three methods to improve the chip heat dissipation performance by reducing the thermal resistance: (1) increasing the thermal conductivity of the material; (2) shortening the heat transfer path; (3) increasing the heat dissipation area. In the current packaging structure, the heat transfer area of the chip is mainly the active surface area of the chip. Considering the production cost of the wafer, generally the area of the chip will not be increased to reduce the thermal resistance. When the thermal conductivity of the material and the heat transfer path remain unchanged, the thermal resistance value will be reduced by half for every doubling of the heat transfer area. Based on this, a vapor chamber can be used to reduce the thermal resistance by increasing the heat transfer area. The current vapor chamber covers the surface of the chip, and a heat dissipation structure is arranged inside the vapor chamber. The heat dissipation structure includes a cavity, a capillary adsorption structure and a working fluid. The working fluid evaporates to the condensation end after absorbing the heat generated by the chip, and re-liquefies at the condensation end and then flows back along the capillary structure. However, when the chip temperature is relatively high, since the capillary structure layer is a rectangular plane and has a large space, when the temperature difference is large, the suction effect of the capillary structure layer directly above the chip is poor, which is likely to cause dry burning. In addition, the processing difficulty and manufacturing cost of the capillary structure layer are relatively high, resulting in a reduction in the yield of the heat dissipation cover and the packaging structure and an increase in the manufacturing cost.

[0004] Therefore, how to improve the chip heat dissipation effect while reducing the manufacturing difficulty and manufacturing cost of the heat dissipation cover and the packaging structure, so as to improve the yield of the heat dissipation cover and the packaging structure and reduce the manufacturing cost, is a technical problem that needs to be solved urgently at present. Summary of the Invention

[0005] The present invention provides a heat dissipation cover, a chip packaging structure and a method for forming the same, which are used to improve the chip heat dissipation effect while reducing the manufacturing difficulty and manufacturing cost of the heat dissipation cover and the packaging structure, so as to improve the yield of the heat dissipation cover and the packaging structure and reduce the manufacturing cost.

[0006] According to some embodiments, the present invention provides a heat dissipation cover, including:

[0007] The support housing includes a top surface and a bottom surface that are relatively distributed. The bottom surface is used to cover the chip, and the area of the top surface of the support housing is larger than the area of the bottom surface of the support housing. A vacuum accommodation cavity is provided inside the support housing;

[0008] The first partition is located between the top surface and the bottom surface of the support housing. A plurality of the first partitions are arranged at intervals and divide the vacuum accommodation cavity into an independent central heat dissipation cavity and a peripheral heat dissipation cavity. The central heat dissipation cavity is located in the middle of the vacuum accommodation cavity, and the peripheral heat dissipation cavity is distributed around the periphery of the central heat dissipation cavity;

[0009] The coolant is located in the central heat dissipation cavity and the peripheral heat dissipation cavity.

[0010] In some embodiments, the support housing is an inverted conical housing, the vacuum accommodation cavity is an inverted conical accommodation cavity, and the area of the top of the vacuum accommodation cavity is larger than the area of the bottom of the vacuum accommodation cavity.

[0011] In some embodiments, both the central heat dissipation cavity and the peripheral heat dissipation cavity are inverted conical heat dissipation cavities, and the area of the top of the central heat dissipation cavity is larger than the area of the bottom of the central heat dissipation cavity, and the area of the top of the peripheral heat dissipation cavity is larger than the area of the bottom of the peripheral heat dissipation cavity.

[0012] In some embodiments, the number of the peripheral heat dissipation cavities is multiple, and in a direction parallel to the top surface of the support housing, the multiple peripheral heat dissipation cavities are nested in sequence.

[0013] In some embodiments, in a direction from the center of the bottom surface of the support housing to the edge of the bottom surface of the support housing, the inner diameters of the multiple peripheral heat dissipation cavities gradually increase.

[0014] In some embodiments, the inner diameter of the central heat dissipation cavity is larger than the inner diameter of any one of the peripheral heat dissipation cavities.

[0015] In some embodiments, the types of the coolant in the multiple peripheral heat dissipation cavities are the same;

[0016] In a direction from the center of the bottom surface of the support housing to the edge of the bottom surface of the support housing, the amount of the coolant in the multiple peripheral heat dissipation cavities gradually decreases.

[0017] In some embodiments, the thermal conductivity of the coolant in the central heat dissipation cavity is higher than the thermal conductivity of the coolant in at least one of the peripheral heat dissipation cavities.

[0018] In some embodiments, each of the peripheral heat dissipation cavities is a continuously distributed annular heat dissipation cavity.

[0019] In some embodiments, it further includes:

[0020] A second partition board, one end of which is connected to the top surface and the other end is connected to the bottom surface. In a direction perpendicular to the top surface of the support housing, the second partition board continuously penetrates through a plurality of the first partition boards and divides each of the outer peripheral heat dissipation cavities into a plurality of independent sub-outer peripheral heat dissipation cavities.

[0021] In some embodiments, the first partition board is an inverted quadrangular pyramid structure, and the second partition board penetrates through the first partition board at the corners of the inverted quadrangular pyramid structure.

[0022] In some embodiments, it further includes:

[0023] A support frame, vertically connected to the end of the top surface of the support housing, and the support frame and the support housing enclose an inner cavity for accommodating the chip.

[0024] In some embodiments, the coolant is deionized water or alcohol.

[0025] According to some other embodiments, the present invention further provides a chip packaging structure, including:

[0026] A chip, including a front surface and a back surface that are oppositely distributed;

[0027] A heat dissipation cover, including a support housing, a first partition board, and a coolant. The support housing includes a top surface and a bottom surface that are oppositely distributed. The bottom surface covers the back surface of the chip, and the area of the top surface of the support housing is larger than the area of the bottom surface of the support housing. The interior of the support housing has a vacuum accommodation cavity. The first partition board is located between the top surface and the bottom surface of the support housing. A plurality of the first partition boards are arranged at intervals and divide the vacuum accommodation cavity into an independent central heat dissipation cavity and an outer peripheral heat dissipation cavity. The central heat dissipation cavity is located in the middle of the vacuum accommodation cavity, and the outer peripheral heat dissipation cavity is distributed around the periphery of the central heat dissipation cavity. The coolant is located in the central heat dissipation cavity and the outer peripheral heat dissipation cavity.

[0028] In some embodiments, it further includes:

[0029] A packaging substrate, the chip is mounted on the packaging substrate, and the front surface of the chip faces the packaging substrate;

[0030] The heat dissipation cover further includes a support frame. The top end of the support frame is vertically connected to the end of the top surface of the support housing, the bottom end of the support frame is connected to the packaging substrate, and the support frame and the support housing enclose an inner cavity, and the chip is located in the inner cavity.

[0031] In some embodiments, the area of the bottom surface of the support housing is greater than or equal to the area of the back surface of the chip.

[0032] In some embodiments, the support housing is an inverted conical housing, the vacuum accommodation cavity is an inverted conical accommodation cavity, and the area of the top of the vacuum accommodation cavity is greater than the area of the bottom of the vacuum accommodation cavity.

[0033] In some embodiments, the central heat dissipation cavity is aligned with the center of the chip;

[0034] The number of the outer peripheral heat dissipation cavities is multiple, and in a direction parallel to the top surface of the support housing, the multiple outer peripheral heat dissipation cavities are nested in sequence.

[0035] In some embodiments, the projection of at least one of the outer peripheral heat dissipation cavities on the bottom surface of the support housing surrounds the outer periphery of the projection of the chip on the bottom surface of the support housing.

[0036] In some embodiments, in a direction from the center of the bottom surface of the support housing towards the edge of the bottom surface of the support housing, the inner diameters of the multiple outer peripheral heat dissipation cavities gradually increase.

[0037] In some embodiments, the types of the coolant in the multiple outer peripheral heat dissipation cavities are the same;

[0038] In a direction from the center of the bottom surface of the support housing towards the edge of the bottom surface of the support housing, the amount of the coolant in the multiple outer peripheral heat dissipation cavities gradually decreases.

[0039] In some embodiments, the heat dissipation cover further includes:

[0040] A second partition plate, one end of which is connected to the top surface and the other end of which is connected to the bottom surface. In a direction perpendicular to the top surface of the support housing, the second partition plate continuously penetrates through the multiple first partition plates and divides each of the outer peripheral heat dissipation cavities into multiple independent sub-outer peripheral heat dissipation cavities.

[0041] In some embodiments, it further includes:

[0042] An external radiator, which is located on the top surface of the support housing.

[0043] According to still some other embodiments, the present invention further provides a method for forming a chip packaging structure, including the following steps:

[0044] A heat dissipation cover is formed. The heat dissipation cover includes a support housing, a first partition board, and a coolant. The support housing includes a top surface and a bottom surface that are oppositely distributed. The area of the top surface of the support housing is larger than the area of the bottom surface of the support housing. The interior of the support housing has a vacuum accommodation cavity. The first partition board is located between the top surface and the bottom surface of the support housing. A plurality of the first partition boards are arranged at intervals and divide the vacuum accommodation cavity into an independent middle heat dissipation cavity and an outer peripheral heat dissipation cavity. The middle heat dissipation cavity is located in the middle of the vacuum accommodation cavity, and the outer peripheral heat dissipation cavity is distributed around the outer periphery of the middle heat dissipation cavity. The coolant is located in the middle heat dissipation cavity and the outer peripheral heat dissipation cavity;

[0045] Mount the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip.

[0046] In some embodiments, before mounting the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip, the following steps are further included:

[0047] Provide a chip, and the chip includes a front surface and a back surface that are oppositely distributed;

[0048] Mount the chip to the packaging substrate such that the front surface of the chip faces the packaging substrate.

[0049] In some embodiments, the heat dissipation cover further includes a support frame. The top end of the support frame is perpendicularly connected to the end of the top surface of the support housing. The support frame and the support housing enclose an inner cavity. The specific steps of mounting the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip include:

[0050] Mount the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip, and mount the support frame to the packaging substrate such that the chip is located in the inner cavity.

[0051] In some embodiments, after mounting the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip, the following steps are further included:

[0052] Mount an external radiator to the top surface of the support housing.

[0053] The heat dissipation cover, chip packaging structure and method for forming the same provided by the present invention are characterized in that a support shell with a vacuum accommodation cavity is arranged in the heat dissipation cover, the area of the top surface of the support shell is larger than the area of the bottom surface of the support shell, and a plurality of longitudinally extending first partitions are arranged inside the vacuum accommodation cavity. The plurality of first partitions are arranged at intervals and divide the vacuum accommodation cavity into an independent central heat dissipation cavity and a peripheral heat dissipation cavity. The central heat dissipation cavity is located in the middle of the vacuum accommodation cavity, and the peripheral heat dissipation cavity is distributed around the periphery of the central heat dissipation cavity and a coolant is filled in both the central heat dissipation cavity and the peripheral heat dissipation cavity. After absorbing the heat generated by the chip, the coolant vaporizes and rises along the central heat dissipation cavity and the peripheral heat dissipation cavity. After reaching the top of the central heat dissipation cavity and the peripheral heat dissipation cavity, it exchanges heat with the relatively cooler air around and re-liquefies, and then flows back to the bottom of the central heat dissipation cavity and the peripheral heat dissipation cavity, thereby realizing the extension of the heat source surface from the back of the chip to the entire upper surface of the packaging structure, increasing the heat dissipation area of the packaging structure by several times, and improving the heat dissipation effect of the chip. At the same time, both the central heat dissipation cavity and the peripheral heat dissipation cavity are vacuum chambers. The coolant filled in the central heat dissipation cavity and the central heat dissipation cavity together form a heat pipe structure, and the coolant filled in the peripheral heat dissipation cavity and the peripheral heat dissipation cavity also together form a heat pipe structure. The heat pipe structure using the liquid phase change heat dissipation technology to realize the heat dissipation function has a thermal conductivity and a transient response efficiency that are dozens of times or even hundreds of times that of pure copper materials. The chip packaging structure provided with the heat dissipation cover has a lower thermal resistance, further improving the heat dissipation performance of the chip and the chip packaging structure.

[0054] Moreover, since the overall heat dissipation cover is designed in an inverted conical shape (i.e., funnel-shaped), after re-liquefying, the coolant can flow back to the bottom of the central heat dissipation cavity and the peripheral heat dissipation cavity along the cavity walls of the central heat dissipation cavity and the peripheral heat dissipation cavity under the action of gravity, thus eliminating the need to set a capillary structure layer, greatly reducing the manufacturing difficulty and manufacturing cost of the heat dissipation cover. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0056] Figure 1 It is a cross-sectional schematic diagram of the heat dissipation cover in the specific embodiment of the present invention;

[0057] Figure 2 It is a cross-sectional schematic diagram of the support shell in the specific embodiment of the present invention;

[0058] Figure 3 It is another cross-sectional schematic diagram of the heat dissipation cover in the specific embodiment of the present invention;

[0059] Figure 4 It is another cross-sectional schematic diagram of the support housing in the specific embodiment of the present invention;

[0060] Figure 5 It is a top view schematic diagram of the heat dissipation cover in the specific embodiment of the present invention;

[0061] Figure 6 It is a side view of the heat dissipation cover in the specific embodiment of the present invention;

[0062] Figure 7 It is a structural schematic diagram of the chip packaging structure in the specific embodiment of the present invention;

[0063] Figure 8 It is another structural schematic diagram of the chip packaging structure in the specific embodiment of the present invention;

[0064] Figure 9 It is a flow chart of the method for forming the chip packaging structure in the specific embodiment of the present invention;

[0065] Figure 10 It is a structural schematic diagram after the chip is mounted on the packaging substrate in the specific embodiment of the present invention;

[0066] Figure 11 It is a structural schematic diagram after the external radiator is mounted on the heat dissipation cover in the specific embodiment of the present invention. Specific Embodiment

[0067] The following will describe in detail the specific embodiments of the heat dissipation cover, chip packaging structure and its forming method provided by the present invention with reference to the accompanying drawings.

[0068] This specific embodiment provides a heat dissipation cover, Figure 1 It is a cross-sectional schematic diagram of the heat dissipation cover in the specific embodiment of the present invention, Figure 2 It is a cross-sectional schematic diagram of the support housing in the specific embodiment of the present invention. As Figure 1 and Figure 2 shown, the heat dissipation cover includes:

[0069] A support housing 10, including a top surface 101 and a bottom surface 102 distributed oppositely, the bottom surface 102 is used to cover the chip, and the area of the top surface 101 of the support housing 10 is larger than the area of the bottom surface 102 of the support housing 10, and a vacuum accommodation cavity is provided inside the support housing 10;

[0070] The first partition plate 121 is located between the top surface 101 and the bottom surface 102 of the support housing 10. A plurality of the first partition plates 121 are arranged at intervals and divide the vacuum accommodation cavity into independent middle heat dissipation cavities 11 and outer peripheral heat dissipation cavities 13. The middle heat dissipation cavity 11 is located in the middle of the vacuum accommodation cavity, and the outer peripheral heat dissipation cavity 13 is distributed around the outer periphery of the middle heat dissipation cavity 11;

[0071] The coolant 15 is located in the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13.

[0072] Specifically, the support housing 10 includes the relatively distributed top surface 101 and the bottom surface 102. The bottom surface 102 is used to cover the surface of the chip to be cooled, and the top surface 101 is used to exchange heat with the surrounding environment or carry an external radiator and exchange heat with the external radiator. The area of the top surface 101 of the support housing 10 is larger than the area of the bottom surface 102 of the support housing 10. For example, in the direction from the bottom surface 102 of the support housing 10 to the top surface 101 of the support housing 10, the width of the support housing 10 gradually increases, so that the overall shape of the support housing 10 is an inverted cone (i.e., funnel-shaped). In one example, the vacuum accommodation cavity inside the support housing 10 is also in an inverted cone shape. In one example, the material of the support housing 10 can be a heat-conducting material, such as metallic copper. A plurality of the first partition plates 121 are distributed between the top surface 101 and the bottom surface 102 of the support housing 10, so as to divide the vacuum accommodation cavity into independent middle heat dissipation cavities 11 and outer peripheral heat dissipation cavities 13, that is, both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 are vacuum chambers. In one example, each first partition plate 121 includes a relatively distributed first end and a second end. The first end of the first partition plate 121 is connected to the top surface 101 of the support housing 10, and the second end of the first partition plate 121 is connected to the bottom surface 102 of the support housing 10. The coolant 15 is filled in both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13.

[0073] After covering the surface of the chip with the heat dissipation cover in the direction of the bottom surface 102 of the support housing 10 facing the chip, the heat generated by the chip is absorbed by the coolant 15 in the middle heat dissipation cavity 11 and the coolant 15 in the outer peripheral heat dissipation cavity 13. In a vacuum environment (both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 are vacuum chambers), the boiling point of the coolant 15 is relatively low. Therefore, after absorbing heat, the coolant 15 will vaporize to form a gas or a gas-liquid mixture. The gas or gas-liquid mixture will rise along the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13. During the process of rising along the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 or when reaching the top of the middle heat dissipation cavity 11 and the top of the outer peripheral heat dissipation cavity 13, the gas or gas-liquid mixture exchanges heat with the relatively low-temperature surrounding environment and re-liquefies to form the coolant 15. The re-liquefied coolant 15 can flow back to the bottom of the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 along the cavity walls of the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 under the action of gravity, thereby realizing the cyclic heat dissipation of the chip through the phase change of the coolant 15.

[0074] In this specific embodiment, by providing the vacuum accommodation cavity in the support housing 10, after the coolant located in the vacuum accommodation cavity re-liquefies, it can flow back to the bottom of the middle heat dissipation cavity and the outer peripheral heat dissipation cavity along the cavity walls of the middle heat dissipation cavity and the outer peripheral heat dissipation cavity under the action of gravity, so that there is no need to provide a capillary structure layer, greatly reducing the manufacturing difficulty and manufacturing cost of the heat dissipation cover. At the same time, in this specific embodiment, by providing the vacuum accommodation cavity in the support housing 10 and filling the coolant 15 in the vacuum accommodation cavity, the heat source surface is extended from the surface of the chip (such as the back surface of the chip) to the entire upper surface of the packaging structure, increasing the heat dissipation area of the packaging structure by several times and realizing the improvement of the chip heat dissipation effect.

[0075] Both the middle heat dissipation cavity and the outer peripheral heat dissipation cavity are vacuum chambers. The coolant filled in the middle heat dissipation cavity and the middle heat dissipation cavity together form a heat pipe structure. The coolant filled in the outer peripheral heat dissipation cavity and the outer peripheral heat dissipation cavity also together form a heat pipe structure. The heat pipe structure using the liquid phase change heat dissipation technology to achieve the heat dissipation function has a thermal conductivity and a transient response efficiency that are dozens or even hundreds of times that of pure copper materials. The chip packaging structure provided with the heat dissipation cover has a lower thermal resistance, further improving the heat dissipation performance of the chip and the chip packaging structure. Moreover, in this specific embodiment, the vacuum accommodation cavity is separated into the independent middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 by the first partition 121, thereby reducing the heat required for the coolant 15 in a single heat dissipation cavity (such as the middle heat dissipation cavity 11 or the outer peripheral heat dissipation cavity 13) to vaporize. Even when the chip generates less heat, it will cause the coolant 15 in the middle heat dissipation cavity 11 or the outer peripheral heat dissipation cavity 13 to absorb heat and vaporize, further improving the heat dissipation efficiency of the heat dissipation cover.

[0076] In some embodiments, the support housing 10 is an inverted conical housing, the vacuum accommodation cavity is an inverted conical accommodation cavity, and the area of the top of the vacuum accommodation cavity is larger than the area of the bottom of the vacuum accommodation cavity.

[0077] In some embodiments, both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 are inverted conical heat dissipation cavities, and the area of the top of the middle heat dissipation cavity 11 is larger than the area of the bottom of the middle heat dissipation cavity 11, and the area of the top of the outer peripheral heat dissipation cavity 13 is larger than the area of the bottom of the outer peripheral heat dissipation cavity 13.

[0078] In this specific embodiment, the area of the top of the vacuum accommodation cavity refers to the projected area of the top of the vacuum accommodation cavity on the top surface 101 of the support housing 10. The area of the bottom of the vacuum accommodation cavity refers to the projected area of the bottom of the vacuum accommodation cavity on the top surface 101 of the support housing 10. The area of the top of the middle heat dissipation cavity 11 refers to the projected area of the top of the middle heat dissipation cavity 11 on the top surface 101 of the support housing 10. The area of the bottom of the middle heat dissipation cavity 11 refers to the projected area of the bottom of the middle heat dissipation cavity 11 on the top surface 101 of the support housing 10. The area of the top of the outer peripheral heat dissipation cavity 13 refers to the projected area of the top of the outer peripheral heat dissipation cavity 13 on the top surface 101 of the support housing 10. The area of the bottom of the outer peripheral heat dissipation cavity 13 refers to the projected area of the bottom of the outer peripheral heat dissipation cavity 13 on the top surface 101 of the support housing 10.

[0079] For example, in the direction from the bottom surface 102 of the support housing 10 towards the top surface 101 of the support housing 10, the width of the vacuum accommodation cavity (e.g., the inner diameter of the vacuum accommodation cavity) gradually increases. The extending direction of the first partition 121 intersects obliquely with the bottom surface 102 of the support housing 10, such that both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 are in an inverted conical shape, that is, the width of the end of the middle heat dissipation cavity 11 facing the bottom surface 102 of the support housing 10 is smaller than the width of the end of the middle heat dissipation cavity 11 facing the top surface 101 of the support housing 10, and the width of the end of the outer peripheral heat dissipation cavity 13 facing the bottom surface 102 of the support housing 10 is smaller than the width of the end of the outer peripheral heat dissipation cavity 13 facing the top surface 101 of the support housing 10. By setting both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 as inverted conical heat dissipation cavities, on the one hand, it can enable the gas or gas-liquid mixture after the coolant vaporizes to be transmitted upward more smoothly; on the other hand, it can increase the contact area between the gas or gas-liquid mixture after the coolant vaporizes and the surrounding relatively cool air, thereby improving the efficiency of the gas or gas-liquid mixture to re-liquefy, that is, further improving the heat dissipation efficiency of the heat dissipation cover.

[0080] In some embodiments, as Figure 1 and Figure 2 shown, the number of the outer peripheral heat dissipation cavities 13 is 1, and the number of the middle heat dissipation cavities 11 is also 1. The outer peripheral heat dissipation cavities 13 are distributed around the outer periphery of the middle heat dissipation cavity 11, so as to improve the heat dissipation effect of the heat dissipation cover while simplifying the structure of the heat dissipation cover, and further reducing the manufacturing difficulty and manufacturing cost of the heat dissipation cover.

[0081] For example, as Figure 1 and Figure 2 shown, the bottom surface 102 of the support housing 10 includes a middle region P1 and a peripheral region P2 distributed around the middle region P1. One end of the first partition 121 is connected between the middle region P1 and the peripheral region P2. For example, one end of the first partition 121 is connected to the junction of the middle region P1 and the peripheral region P2. The projection of the middle heat dissipation cavity 11 on the bottom surface 102 of the support housing 10 covers the middle region P1, and the projection of the outer peripheral heat dissipation cavity 13 on the bottom surface 102 of the support housing 10 covers the peripheral region P2.

[0082] Figure 3 is another cross-sectional schematic view of the heat dissipation cover in the specific embodiment of the present invention, Figure 4 is another cross-sectional schematic view of the support housing in the specific embodiment of the present invention, Figure 5It is a top view schematic diagram of the heat dissipation cover in the specific embodiment of the present invention. Figure 6 It is a side view of the heat dissipation cover in the specific embodiment of the present invention. In some other embodiments, such as Figure 3 , Figure 4 , Figure 5 and Figure 6 shown, the number of the peripheral heat dissipation cavities 13 is multiple, and in the direction parallel to the top surface 101 of the support housing 10, the multiple peripheral heat dissipation cavities 13 are nested in sequence to match chips of different sizes, thereby expanding the application range of the heat dissipation cover.

[0083] Specifically, as Figures 3 - 6 shown, the bottom surface 102 of the support housing 10 includes a central region P1 and a peripheral region distributed around the central region P1. The number of the peripheral heat dissipation cavities 13 is multiple, the number of the central heat dissipation cavity 11 is one, and the projection of the central heat dissipation cavity 11 on the bottom surface 102 of the support housing 10 covers the central region P1. The number of the peripheral heat dissipation cavities 13 is multiple, and in the direction parallel to the top surface 101 of the support housing 10, the fact that the multiple peripheral heat dissipation cavities 13 are nested in sequence means that for two adjacent peripheral heat dissipation cavities 13, the peripheral heat dissipation cavity 13 farther from the central heat dissipation cavity 11 is distributed around the periphery of the peripheral heat dissipation cavity 13 closer to the central heat dissipation cavity 11.

[0084] In this specific embodiment, by providing multiple peripheral heat dissipation cavities 13 distributed around the central heat dissipation cavity 11 and the multiple peripheral heat dissipation cavities 13 being nested in sequence, it is because different chips have different sizes due to different structures and functions, but the functional regions of chips of different sizes are mainly located in the middle of the chips. Therefore, when attaching the heat dissipation cover to the surfaces of chips of different sizes, as long as the middle of the heat dissipation cover is aligned with the middle of the chip, effective heat dissipation of the chip can be achieved, thereby greatly improving the adaptability of the heat dissipation cover to chips of different sizes.

[0085] In some embodiments, in the direction from the center of the bottom surface 102 of the support housing 10 to the edge of the bottom surface 102 of the support housing 10, the inner diameters of the multiple peripheral heat dissipation cavities 13 gradually increase.

[0086] In some embodiments, the inner diameter of the central heat dissipation cavity 11 is greater than the inner diameter of any one of the peripheral heat dissipation cavities 13.

[0087] In some embodiments, the types of the coolant in the multiple peripheral heat dissipation cavities 13 are the same;

[0088] In the direction pointing from the center of the bottom surface 102 of the support housing 10 to the edge of the bottom surface 102 of the support housing 10, the amount of the coolant in the plurality of the outer peripheral heat dissipation cavities 13 gradually decreases.

[0089] Specifically, when the amount of the coolant 15 filled in the outer peripheral heat dissipation cavity 13 is small, when the temperature of the chip area corresponding to the outer peripheral heat dissipation cavity 13 slightly increases, the coolant 15 in the outer peripheral heat dissipation cavity 13 immediately absorbs heat and vaporizes. Although the heat transfer efficiency is high, dry burning is likely to occur. When the amount of the coolant 15 filled in the outer peripheral heat dissipation cavity 13 is large, the vaporization efficiency of the coolant 15 in the outer peripheral heat dissipation cavity 13 is slow, resulting in a low heat dissipation efficiency, but dry burning is not likely to occur. Since the temperature change range of the chip area corresponding to the outer peripheral heat dissipation cavity 13 that is farther away from the central heat dissipation cavity 11 is smaller, by making the inner diameters of the plurality of the outer peripheral heat dissipation cavities 13 gradually increase in the direction pointing from the center of the bottom surface 102 of the support housing 10 to the edge of the bottom surface 102 of the support housing 10, and the amount of the coolant 15 in the plurality of the outer peripheral heat dissipation cavities 13 gradually decreases, that is, making the filling rate of the coolant 15 in the plurality of the outer peripheral heat dissipation cavities 13 gradually decrease, the coolant in the outer peripheral heat dissipation cavity 13 that is farther away from the central heat dissipation cavity 11 only needs a smaller temperature difference to vaporize, so that the heat transfer efficiency of the outer peripheral heat dissipation cavity can be improved.

[0090] In an example, the amount of the coolant 15 filled in the central heat dissipation cavity 11 is greater than the amount of the coolant 15 filled in any of the outer peripheral heat dissipation cavities 13 because most of the functional areas of the chip are concentrated in the middle of the chip. By increasing the amount of the coolant 15 in the central heat dissipation cavity 11, the heat generated in the middle of the chip can be quickly absorbed, avoiding overheating in the middle of the chip.

[0091] In some other embodiments, the thermal conductivity of the coolant 15 in the central heat dissipation cavity 11 is higher than the thermal conductivity of the coolant 15 in at least one of the outer peripheral heat dissipation cavities 13.

[0092] In one example, the thermal conductivity of the coolant 15 in the central heat dissipation cavity 11 is higher than that of the coolant 15 in the peripheral heat dissipation cavities 13. The types of the coolant 15 in all the peripheral heat dissipation cavities 13 are the same. The amount of the coolant 15 filled in the central heat dissipation cavity 11 is greater than that of the coolant 15 filled in any one of the peripheral heat dissipation cavities 13. In the direction from the center of the bottom surface 102 of the support housing 10 to the edge of the bottom surface 102 of the support housing 10, the amount of the coolant in the plurality of peripheral heat dissipation cavities 13 gradually decreases. Thereby, it can not only improve the heat dissipation efficiency of the chip, but also prevent the dry burning phenomenon during the continuous operation of the chip while ensuring the heat transfer efficiency of the heat dissipation cover.

[0093] In some embodiments, each of the peripheral heat dissipation cavities 13 is a continuously distributed annular heat dissipation cavity, thereby further simplifying the manufacturing process of the heat dissipation cover.

[0094] In other embodiments, as Figures 3 - 6 shown, the heat dissipation cover further includes:

[0095] A second partition 122, one end of which is connected to the top surface 101 and the other end of which is connected to the bottom surface 102. In the direction perpendicular to the top surface 101 of the support housing 10, the second partition 122 continuously penetrates through a plurality of the first partitions 121 and divides each of the peripheral heat dissipation cavities 13 into a plurality of independent sub-peripheral heat dissipation cavities 131.

[0096] For example, as Figure 5 shown, the heat dissipation cover includes a plurality of the first partitions 121 and a plurality of the second partitions 122. The opposite ends of each of the first partitions 121 are respectively connected to the top surface 101 of the support housing 10 and the bottom surface 102 of the support housing 10, thereby dividing the vacuum accommodation cavity into the central heat dissipation cavity 11 and a plurality of the peripheral heat dissipation cavities 13. The opposite ends of each of the second partitions 122 are also respectively connected to the top surface 101 of the support housing 10 and the bottom surface 102 of the support housing 10, and the second partition 122 continuously penetrates through a plurality of the first partitions 121 along the extending direction of the first partition 121 (for example, the direction from the bottom surface 102 of the support housing 10 to the top surface 101 of the support housing 10), thereby dividing each of the peripheral heat dissipation cavities 13 into a plurality of independent sub-peripheral heat dissipation cavities 131 and dividing the central heat dissipation cavity 11 into a plurality of independent sub-central heat dissipation cavities 111. By dividing the peripheral heat dissipation cavities 13 and the central heat dissipation cavity 11 by the second partition 122, the amount of the coolant 15 in each independent chamber is relatively small, which helps to improve the vaporization efficiency of the coolant 15, and further improves the heat dissipation efficiency of the heat dissipation cover.

[0097] In some embodiments, to further improve the uniformity of heat dissipation of the heat dissipation cover, the first partition plate 121 is of an inverted quadrangular pyramid structure, and the second partition plate 122 penetrates through the first partition plate 121 at the corners of the inverted quadrangular pyramid structure.

[0098] In one example, the first partition plate 121 is of an inverted quadrangular pyramid structure, the number of the second partition plates 122 is four, and the four second partition plates 122 penetrate through the first partition plate 121 at the four corners of the inverted quadrangular pyramid structure respectively, so as to equally divide each of the peripheral heat dissipation cavities 13 into four sub-peripheral heat dissipation cavities 131 and equally divide the middle heat dissipation cavity 11 into four sub-middle heat dissipation cavities 111, thereby improving the uniformity of heat dissipation.

[0099] In some embodiments, the heat dissipation cover further includes:

[0100] A support frame 14, vertically connected to the end of the top surface 101 of the support housing 10, and the support frame 14 and the support housing 10 enclose an inner cavity for accommodating the chip.

[0101] Specifically, the support frame 14 is in a frame shape and is connected to the end of the top surface 101 of the support housing 10, for supporting the support housing 10 and for connecting to structures such as a packaging substrate.

[0102] In some embodiments, the coolant is deionized water or alcohol.

[0103] This specific embodiment also provides a chip packaging structure. Figure 7 It is a schematic structural diagram of the chip packaging structure in the specific embodiment of the present invention. Figure 8 It is another schematic structural diagram of the chip packaging structure in the specific embodiment of the present invention. For the schematic diagram of the heat dissipation cover in the chip packaging structure, reference can be made to Figures 1 - 6 .

[0104] As Figures 1 - 8 shown, the chip packaging structure includes:

[0105] A chip 70, including a front surface and a back surface that are oppositely distributed;

[0106] The heat dissipation cover includes a support housing 10, a first partition 121, and a coolant 15. The support housing 10 includes a top surface 101 and a bottom surface 102 that are oppositely distributed. The bottom surface 102 covers the back surface of the chip 70, and the area of the top surface 101 of the support housing 10 is larger than the area of the bottom surface 102 of the support housing 10. The interior of the support housing 10 has a vacuum accommodation cavity. The first partition 121 is located between the top surface 101 and the bottom surface 102 of the support housing 10. A plurality of the first partitions 121 are arranged at intervals and divide the vacuum accommodation cavity into independent middle heat dissipation cavities 11 and peripheral heat dissipation cavities 13. The middle heat dissipation cavity 11 is located in the middle of the vacuum accommodation cavity, and the peripheral heat dissipation cavity 13 is distributed around the periphery of the middle heat dissipation cavity 11. The coolant 15 is located in the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13.

[0107] Specifically, the chip 70 includes a front surface and a back surface that are oppositely distributed. The heat dissipation cover is mounted on the back surface of the chip 70 by means of a TIM (Thermal Interface Material) adhesive 72 with the bottom surface 102 of the support housing 10 facing the chip 70. In one example, the position of the middle heat dissipation cavity 11 in the heat dissipation cover is aligned with the middle of the chip 70.

[0108] After the heat dissipation cover is mounted on the back surface of the chip 70, the heat generated by the chip 70 during operation is absorbed by the coolant 15 in the middle heat dissipation cavity 11 and the coolant 15 in the peripheral heat dissipation cavity 13. In a vacuum environment (both the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13 are vacuum chambers), the boiling point of the coolant 15 is relatively low. Therefore, after the coolant 15 absorbs heat, it will vaporize to form a gas or a gas-liquid mixture. The gas or gas-liquid mixture will rise along the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13. During the process of rising along the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13 or when reaching the tops of the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13, the gas or gas-liquid mixture exchanges heat with the relatively low-temperature surrounding environment and re-liquefies to form the coolant 15. The re-liquefied coolant 15 can flow back along the cavity walls of the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13 to the bottoms of the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13 (i.e., the middle heat dissipation cavity 11 and the peripheral heat dissipation cavity 13 serve as the flow channels for the re-liquefied coolant 15) under the action of gravity to absorb the heat generated by the chip 70 again, thereby realizing the cyclic heat dissipation of the chip through the phase change of the coolant 15.

[0109] In this specific embodiment, by providing the vacuum accommodation cavity within the support housing 10, after the coolant located within the vacuum accommodation cavity re-liquefies, it can flow back to the bottoms of the central heat dissipation cavity and the peripheral heat dissipation cavity along the cavity walls of the central heat dissipation cavity and the peripheral heat dissipation cavity under the action of gravity. Thus, there is no need to provide a capillary structure layer, significantly reducing the manufacturing difficulty and cost of the heat dissipation cover and the chip packaging structure. At the same time, in this specific embodiment, by providing the vacuum accommodation cavity within the support housing 10 and filling the coolant 15 within the vacuum accommodation cavity, the heat source surface is extended from the surface of the chip (such as the back surface of the chip) to the entire upper surface of the chip packaging structure, increasing the heat dissipation area of the chip packaging structure by several times and achieving an improvement in the heat dissipation effect of the chip packaging structure.

[0110] Both the central heat dissipation cavity and the peripheral heat dissipation cavity are vacuum chambers. The coolant filled in the central heat dissipation cavity and the central heat dissipation cavity together form a heat pipe structure. The coolant filled in the peripheral heat dissipation cavity and the peripheral heat dissipation cavity also together form a heat pipe structure. The heat pipe structure that utilizes the liquid-phase change heat dissipation technology to achieve the heat dissipation function has a thermal conductivity and a transient response efficiency that are dozens of times or even hundreds of times that of pure copper materials. The chip packaging structure provided with the heat dissipation cover has a lower thermal resistance, further improving the heat dissipation performance of the chip and the chip packaging structure. Moreover, in this specific embodiment, the vacuum accommodation cavity is separated into the independent central heat dissipation cavity 11 and the peripheral heat dissipation cavity 13 by the first partition 121, thereby reducing the heat required for the coolant 15 to vaporize in a single heat dissipation cavity (such as the central heat dissipation cavity 11 or the peripheral heat dissipation cavity 13). Even when the chip generates less heat, it will cause the coolant 15 in the central heat dissipation cavity 11 or the peripheral heat dissipation cavity 13 to absorb heat and vaporize, further enhancing the heat dissipation efficiency of the heat dissipation cover.

[0111] In some embodiments, the chip packaging structure further includes:

[0112] A packaging substrate 71, the chip 70 is mounted on the packaging substrate 71, and the front surface of the chip 70 faces the packaging substrate 71;

[0113] The heat dissipation cover further includes a support frame 14. The top end of the support frame 14 is perpendicularly connected to the end of the top surface 101 of the support housing 10. The bottom end of the support frame 14 is connected to the packaging substrate 71. The support frame 14 and the support housing 10 enclose an inner cavity, and the chip 70 is located within the inner cavity.

[0114] For example, the encapsulation substrate 71 may be, but is not limited to, a PCB circuit board. A redistribution layer is provided inside the encapsulation substrate 71. The chip 70 is mounted on the surface of the encapsulation substrate 71 with the front side of the chip 70 facing the encapsulation substrate 71, that is, the chip 70 is flip-chip mounted on the surface of the encapsulation substrate 71, and the chip 70 is electrically connected to the redistribution layer inside the encapsulation substrate 71 through structures such as conductive bumps, so as to lead out the signals in the chip 70 or transmit control signals to the chip 70. The support frame 14 is fixedly connected to the surface of the encapsulation substrate 71 through structures such as adhesive. In one example, a plurality of passive devices are further provided on the surface of the encapsulation substrate 71. The passive devices are electrically connected to the redistribution layer, and the passive devices are distributed around the chip 70 and are also located in the inner cavity. Among them, the passive device may be a resistor or a capacitor.

[0115] In order to further sufficiently dissipate heat from the chip 70, in some embodiments, the area of the bottom surface 102 of the support housing 10 is greater than or equal to the area of the back surface of the chip 70.

[0116] In some embodiments, the support housing 10 is an inverted conical housing, the vacuum accommodating cavity is an inverted conical accommodating cavity, and the area of the top of the vacuum accommodating cavity is greater than the area of the bottom of the vacuum accommodating cavity.

[0117] Specifically, the support housing 10 is of an inverted conical structure, and the vacuum accommodating cavity inside the support housing 10 is also of an inverted conical structure. The extending direction of the first partition 121 intersects the bottom surface 102 of the support housing 10 obliquely, so that both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 are of an inverted conical shape, that is, the width of the end of the middle heat dissipation cavity 11 facing the bottom surface 102 of the support housing 10 is smaller than the width of the end of the middle heat dissipation cavity 11 facing the top surface 101 of the support housing 10, and the width of the end of the outer peripheral heat dissipation cavity 13 facing the bottom surface 102 of the support housing 10 is smaller than the width of the end of the outer peripheral heat dissipation cavity 13 facing the top surface 101 of the support housing 10. By setting both the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13 as inverted conical heat dissipation cavities, on the one hand, it can make the gas or gas-liquid mixture after the coolant vaporizes transmit upward more smoothly; on the other hand, it can increase the contact area between the gas or gas-liquid mixture after the coolant vaporizes and the surrounding relatively cold air, thereby improving the efficiency of re-liquefaction of the gas or gas-liquid mixture, that is, further improving the heat dissipation efficiency of the heat dissipation cover.

[0118] In some embodiments, the middle heat dissipation cavity 11 is aligned with the center of the chip 70;

[0119] The number of the peripheral heat dissipation cavities 13 is multiple, and in a direction parallel to the top surface 101 of the support housing 10, the multiple peripheral heat dissipation cavities 13 are nested in sequence.

[0120] For example, the central heat dissipation cavity 11 is aligned with the center of the chip 70, and in a direction parallel to the top surface 101 of the support housing 10, the multiple peripheral heat dissipation cavities 13 are nested in sequence, so that the chip 70 can be dissipated from the central region to the edge region through the central heat dissipation cavity 11 and the multiple peripheral heat dissipation cavities 13 respectively. While ensuring uniform heat dissipation of the chip 70, the heat dissipation efficiency of the chip packaging structure is further improved.

[0121] In some embodiments, the projection of at least one of the peripheral heat dissipation cavities 13 on the bottom surface 102 of the support housing 10 surrounds the periphery of the projection of the chip 70 on the bottom surface 102 of the support housing 10, so that the entire back surface of the chip 70 can exchange heat with the coolant 15, and the heat in the inner cavity can be dissipated through the peripheral heat dissipation cavities 13 located outside the chip 70, thereby further improving the heat dissipation efficiency of the chip packaging structure.

[0122] In some embodiments, in a direction from the center of the bottom surface 102 of the support housing 10 to the edge of the bottom surface 102 of the support housing 10, the inner diameters of the multiple peripheral heat dissipation cavities 13 gradually increase.

[0123] In some embodiments, the types of the coolant in the multiple peripheral heat dissipation cavities 13 are the same;

[0124] In a direction from the center of the bottom surface 102 of the support housing 10 to the edge of the bottom surface 102 of the support housing 10, the amount of the coolant in the multiple peripheral heat dissipation cavities 13 gradually decreases.

[0125] Specifically, when the amount of the coolant 15 filled in the outer peripheral heat dissipation cavity 13 is small, when the temperature of the chip 70 region corresponding to the outer peripheral heat dissipation cavity 13 slightly increases, the coolant 15 in the outer peripheral heat dissipation cavity 13 immediately absorbs heat and vaporizes. Although the heat transfer efficiency is high, dry burning is likely to occur. When the amount of the coolant 15 filled in the outer peripheral heat dissipation cavity 13 is large, the vaporization efficiency of the coolant 15 in the outer peripheral heat dissipation cavity 13 is slow, resulting in a low heat dissipation efficiency, but dry burning is not likely to occur. Since the temperature change range of the chip region corresponding to the outer peripheral heat dissipation cavity 13 farther away from the central heat dissipation cavity 11 is smaller, by making the inner diameters of the plurality of outer peripheral heat dissipation cavities 13 gradually increase in the direction from the center of the bottom surface 102 of the support housing 10 to the edge of the bottom surface 102 of the support housing 10, and the amount of the coolant 15 in the plurality of outer peripheral heat dissipation cavities 13 gradually decreases, that is, the filling rate of the coolant 15 in the plurality of outer peripheral heat dissipation cavities 13 gradually decreases, the coolant in the outer peripheral heat dissipation cavity 13 farther away from the central heat dissipation cavity 11 only needs a smaller temperature difference to vaporize, thereby improving the heat transfer efficiency of the outer peripheral heat dissipation cavity.

[0126] In one example, the amount of the coolant 15 filled in the central heat dissipation cavity 11 is greater than the amount of the coolant 15 filled in any one of the outer peripheral heat dissipation cavities 13 because most of the functional regions of the chip 70 are concentrated in the middle of the chip 70. By increasing the amount of the coolant 15 in the central heat dissipation cavity 11, the heat generated in the middle of the chip can be quickly absorbed, avoiding overheating of the middle region of the chip 70.

[0127] In some embodiments, the heat dissipation cover further includes:

[0128] A second partition plate 122, one end of which is connected to the top surface 101 and the other end of which is connected to the bottom surface 102. In the direction perpendicular to the top surface 101 of the support housing 10, the second partition plate 122 continuously penetrates through a plurality of the first partition plates 121 and divides each of the outer peripheral heat dissipation cavities 13 into a plurality of independent sub-outer peripheral heat dissipation cavities 131.

[0129] For example, the first partition plate 121 is an inverted quadrangular pyramid structure, the number of the second partition plates 122 is four, and the four second partition plates 122 penetrate through the first partition plate 121 at the four corners of the inverted quadrangular pyramid structure respectively, thereby dividing each of the outer peripheral heat dissipation cavities 13 into four sub-outer peripheral heat dissipation cavities 131 on average, and dividing the central heat dissipation cavity 11 into four sub-central heat dissipation cavities 111 on average.

[0130] In some embodiments, the chip packaging structure further includes:

[0131] The external radiator is located on the top surface 101 of the support housing 10.

[0132] Specifically, by providing the external radiator, the heat dissipation efficiency of the chip packaging structure can be further improved. In one example, the external radiator can be an air-cooled radiator or a liquid-cooled radiator. In one example, the area of the surface of the external radiator facing the support housing 10 is greater than or equal to the area of the top surface 101 of the support housing 10.

[0133] This specific embodiment also provides a method for forming a chip packaging structure. Figure 9 It is a flowchart of the method for forming the chip packaging structure in the specific embodiment of the present invention. A schematic diagram of the packaging structure formed in this specific embodiment can be seen in Figure 7 or Figure 8 . As Figure 7 , Figure 8 and Figure 9 shown, the method for forming the chip packaging structure includes the following steps:

[0134] Step S91, forming a heat dissipation cover, the heat dissipation cover includes a support housing 10, a first partition 121, and a coolant 15. The support housing 10 includes a top surface 101 and a bottom surface 102 that are oppositely distributed. The area of the top surface 101 of the support housing 10 is greater than the area of the bottom surface 102 of the support housing 10. The interior of the support housing 10 has a vacuum accommodation cavity. The first partition 121 is located between the top surface 101 and the bottom surface 102 of the support housing 10. A plurality of the first partitions 121 are arranged at intervals and divide the vacuum accommodation cavity into independent middle heat dissipation cavities 11 and outer peripheral heat dissipation cavities 13. The middle heat dissipation cavity 11 is located in the middle of the vacuum accommodation cavity, and the outer peripheral heat dissipation cavity 13 is distributed around the periphery of the middle heat dissipation cavity 13. The coolant 15 is located in the middle heat dissipation cavity 11 and the outer peripheral heat dissipation cavity 13.

[0135] Step S92, mounting the heat dissipation cover to the back surface of the chip 70 in the direction of the bottom surface 102 of the support housing 10.

[0136] Figure 10 It is a schematic structural diagram after mounting the chip to the packaging substrate in the specific embodiment of the present invention. In some embodiments, before mounting the heat dissipation cover to the back surface of the chip 70 in the direction of the bottom surface 102 of the support housing 10, the following steps are further included:

[0137] Providing a chip 70, the chip 70 includes a front surface and a back surface that are oppositely distributed;

[0138] Mount the chip 70 onto the packaging substrate 71 such that the front side of the chip 70 faces the packaging substrate 71, as Figure 10 shown.

[0139] Specifically, a plurality of conductive bumps are provided on the front side of the chip 70. When mounting the chip 70 onto the surface of the packaging substrate 71, the conductive bumps on the front side of the chip 70 face the packaging substrate 71, so as to achieve electrical connection between the chip 70 and the packaging substrate 71 while mounting the chip 70 onto the surface of the packaging substrate 71.

[0140] In some embodiments, the heat dissipation cover further includes a support frame 14. The top end of the support frame 14 is perpendicularly connected to the end of the top surface 101 of the support housing 10. The support frame 14 and the support housing 10 enclose an inner cavity. The specific steps of mounting the heat dissipation cover onto the back surface of the chip 70 along the direction from the bottom surface 102 of the support housing 10 towards the chip 70 include:

[0141] Mount the heat dissipation cover onto the back surface of the chip 70 along the direction from the bottom surface 102 of the support housing 10 towards the chip 70, and mount the support frame 14 onto the packaging substrate 71 such that the chip 70 is located in the inner cavity.

[0142] Figure 11 It is a schematic structural diagram after an external radiator is mounted onto the heat dissipation cover in the specific embodiment of the present invention. In some embodiments, after mounting the heat dissipation cover onto the back surface of the chip 70 along the direction from the bottom surface 102 of the support housing 10 towards the chip 70, the following steps are further included:

[0143] Mount an external radiator 110 onto the top surface 101 of the support housing 10, as Figure 11 shown.

[0144] Specifically, by setting the size of the top surface 101 of the support housing 10 to be larger than the size of the bottom surface 102 of the support housing 10, while increasing the heat dissipation area, it is also convenient to carry the external radiator 110 and disperse the pressure exerted by the external radiator 110 onto the heat dissipation cover. In one example, the external radiator can be an air-cooled radiator or a liquid-cooled radiator.

[0145] The heat dissipation cover, chip packaging structure and method for forming the same provided by this specific embodiment are configured such that a support housing having a vacuum accommodation cavity is provided in the heat dissipation cover, and the area of the top surface of the support housing is larger than the area of the bottom surface of the support housing. A plurality of longitudinally extending first partitions are provided inside the vacuum accommodation cavity. The plurality of first partitions are arranged at intervals and divide the vacuum accommodation cavity into an independent central heat dissipation cavity and a peripheral heat dissipation cavity. The central heat dissipation cavity is located in the middle of the vacuum accommodation cavity, and the peripheral heat dissipation cavity is distributed around the periphery of the central heat dissipation cavity. Coolant is filled in both the central heat dissipation cavity and the peripheral heat dissipation cavity. After absorbing the heat generated by the chip, the coolant vaporizes and rises along the central heat dissipation cavity and the peripheral heat dissipation cavity. When it reaches the top of the central heat dissipation cavity and the peripheral heat dissipation cavity, it exchanges heat with the relatively cooler air around it and re-liquefies, and then flows back to the bottom of the central heat dissipation cavity and the peripheral heat dissipation cavity. Thus, the heat source surface is extended from the back surface of the chip to the entire upper surface of the packaging structure, increasing the heat dissipation area of the packaging structure by several times and improving the heat dissipation effect of the chip. At the same time, both the central heat dissipation cavity and the peripheral heat dissipation cavity are vacuum chambers. The coolant filled in the central heat dissipation cavity and the central heat dissipation cavity together form a heat pipe structure, and the coolant filled in the peripheral heat dissipation cavity and the peripheral heat dissipation cavity also together form a heat pipe structure. The heat pipe structure that uses the liquid-phase change heat dissipation technology to achieve the heat dissipation function has a thermal conductivity and a transient response efficiency that are dozens of times or even hundreds of times that of pure copper materials. The chip packaging structure provided with the heat dissipation cover has a lower thermal resistance, further improving the heat dissipation performance of the chip and the chip packaging structure.

[0146] Moreover, since the heat dissipation cover is designed as an inverted cone (i.e., funnel-shaped) as a whole, the re-liquefied coolant can flow back to the bottom of the central heat dissipation cavity and the peripheral heat dissipation cavity along the cavity walls of the central heat dissipation cavity and the peripheral heat dissipation cavity under the action of gravity, thus eliminating the need to provide a capillary structure layer, greatly reducing the manufacturing difficulty and manufacturing cost of the heat dissipation cover.

[0147] It should be noted that the terms "including" and "having" and their variants involved in the documents of the present invention are intended to cover non-exclusive inclusion. The terms "first", "second", etc. are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. Unless the context clearly indicates otherwise, it should be understood that the data used in this way can be interchanged under appropriate circumstances. The term "one or more" depends at least in part on the context and can be used to describe a feature, structure or property in a singular sense, or can be used to describe a combination of features, structures or features in a plural sense. The term "based on" can be understood as not necessarily intended to express a set of exclusive factors, but rather, alternatively, and also at least in part depending on the context, allows for the existence of other factors that are not necessarily explicitly described. Additionally, in the case of no conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. Furthermore, in the above description, the description of well-known components and technologies is omitted to avoid unnecessarily confusing the concepts of the present invention. In each of the above embodiments, the key point of each embodiment is to illustrate the differences from other embodiments. For the same / similar parts among the embodiments, reference can be made to each other.

[0148] The above is only the preferred embodiment of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A heat dissipation cover, characterized in that, Comprising: A support housing, including a top surface and a bottom surface that are relatively distributed, the bottom surface being used to cover the chip, and the area of the top surface of the support housing being larger than the area of the bottom surface of the support housing, and a vacuum accommodation cavity being provided inside the support housing; A first partition board, located between the top surface and the bottom surface of the support housing, a plurality of the first partition boards being arranged at intervals and dividing the vacuum accommodation cavity into an independent middle heat dissipation cavity and an outer peripheral heat dissipation cavity, the middle heat dissipation cavity being located in the middle of the vacuum accommodation cavity, and the outer peripheral heat dissipation cavity being distributed around the outer periphery of the middle heat dissipation cavity; Coolant, located in the middle heat dissipation cavity and the outer peripheral heat dissipation cavity.

2. The heat dissipation cover according to claim 1, characterized in that, The support housing is an inverted conical housing, the vacuum accommodation cavity is an inverted conical accommodation cavity, and the area of the top of the vacuum accommodation cavity is larger than the area of the bottom of the vacuum accommodation cavity.

3. The heat dissipation cover according to claim 1, wherein Both the middle heat dissipation cavity and the outer peripheral heat dissipation cavity are inverted conical heat dissipation cavities, and the area of the top of the middle heat dissipation cavity is larger than the area of the bottom of the middle heat dissipation cavity, and the area of the top of the outer peripheral heat dissipation cavity is larger than the area of the bottom of the outer peripheral heat dissipation cavity.

4. The heat dissipation cover according to claim 1, characterized in that The number of the outer peripheral heat dissipation cavities is multiple, and in a direction parallel to the top surface of the support housing, the multiple outer peripheral heat dissipation cavities are nested in sequence.

5. The heat dissipation cover according to claim 4, wherein, In a direction from the center of the bottom surface of the support housing to the edge of the bottom surface of the support housing, the inner diameters of the multiple outer peripheral heat dissipation cavities gradually increase.

6. The heat dissipation cover according to claim 5, wherein The inner diameter of the middle heat dissipation cavity is larger than the inner diameter of any one of the outer peripheral heat dissipation cavities.

7. The heat dissipation cover according to claim 5, wherein The types of the coolant in the multiple outer peripheral heat dissipation cavities are the same; In a direction from the center of the bottom surface of the support housing to the edge of the bottom surface of the support housing, the amount of the coolant in the multiple outer peripheral heat dissipation cavities gradually decreases.

8. The heat dissipation cover according to claim 5, characterized in that, The thermal conductivity coefficient of the coolant in the middle heat dissipation cavity is higher than the thermal conductivity coefficient of the coolant in at least one of the outer peripheral heat dissipation cavities.

9. The heat dissipation cover according to claim 4, wherein, Each of the outer peripheral heat dissipation cavities is a continuously distributed annular heat dissipation cavity.

10. The heat dissipation cover according to claim 4, characterized in that, Further comprising: A second partition board, one end of which is connected to the top surface and the other end of which is connected to the bottom surface, and in a direction perpendicular to the top surface of the support housing, the second partition board continuously penetrates through a plurality of the first partition boards and divides each of the outer peripheral heat dissipation cavities into a plurality of independent sub-outer peripheral heat dissipation cavities.

11. The heat dissipation cover according to claim 10, wherein The first partition board is an inverted quadrangular pyramid structure, and the second partition board penetrates through the first partition board at the corner of the inverted quadrangular pyramid structure.

12. The heat dissipation cover according to claim 1, characterized in that, Further comprising: A support frame, vertically connected to the end of the top surface of the support housing, and the support frame and the support housing enclose an inner cavity for accommodating the chip.

13. The heat dissipation cover according to claim 1, characterized in that, The coolant is deionized water or alcohol.

14. A chip packaging structure, characterized in that, Comprising: A chip, including a front surface and a back surface that are relatively distributed; The heat dissipation cover includes a support housing, a first partition board, and a coolant. The support housing includes a top surface and a bottom surface that are oppositely distributed. The bottom surface covers the back surface of the chip, and the area of the top surface of the support housing is larger than the area of the bottom surface of the support housing. The interior of the support housing has a vacuum accommodation cavity. The first partition board is located between the top surface and the bottom surface of the support housing. A plurality of the first partition boards are arranged at intervals and divide the vacuum accommodation cavity into an independent middle heat dissipation cavity and an outer peripheral heat dissipation cavity. The middle heat dissipation cavity is located in the middle of the vacuum accommodation cavity, and the outer peripheral heat dissipation cavity is distributed around the outer periphery of the middle heat dissipation cavity. The coolant is located in the middle heat dissipation cavity and the outer peripheral heat dissipation cavity.

15. The chip package structure according to claim 14, wherein It further includes: A packaging substrate, on which the chip is mounted, and the front surface of the chip faces the packaging substrate; The heat dissipation cover further includes a support frame. The top end of the support frame is vertically connected to the end of the top surface of the support housing, and the bottom end of the support frame is connected to the packaging substrate. The support frame and the support housing enclose an inner cavity, and the chip is located in the inner cavity.

16. The chip package structure according to claim 14, wherein The area of the bottom surface of the support housing is larger than or equal to the area of the back surface of the chip.

17. The chip packaging structure according to claim 14, wherein, The support housing is an inverted conical housing, the vacuum accommodation cavity is an inverted conical accommodation cavity, and the area of the top of the vacuum accommodation cavity is larger than the area of the bottom of the vacuum accommodation cavity.

18. The chip package structure according to claim 14, wherein The middle heat dissipation cavity is aligned with the center of the chip; The number of the outer peripheral heat dissipation cavities is multiple, and in the direction parallel to the top surface of the support housing, a plurality of the outer peripheral heat dissipation cavities are nested in sequence.

19. The chip packaging structure according to claim 18, wherein, At least one of the outer peripheral heat dissipation cavities is distributed around the outer periphery of the projection of the chip on the bottom surface of the support housing in the projection of the support housing on the bottom surface.

20. The chip packaging structure according to claim 18, wherein, In the direction from the center of the bottom surface of the support housing to the edge of the bottom surface of the support housing, the inner diameters of a plurality of the outer peripheral heat dissipation cavities gradually increase.

21. The chip packaging structure according to claim 20, wherein The types of the coolant in a plurality of the outer peripheral heat dissipation cavities are the same; In the direction from the center of the bottom surface of the support housing to the edge of the bottom surface of the support housing, the amounts of the coolant in a plurality of the outer peripheral heat dissipation cavities gradually decrease.

22. The chip packaging structure according to claim 18, wherein, The heat dissipation cover further includes: a second partition board, one end of which is connected to the top surface and the other end of which is connected to the bottom surface. In the direction perpendicular to the top surface of the support housing, the second partition board continuously penetrates a plurality of the first partition boards and divides each of the outer peripheral heat dissipation cavities into a plurality of independent sub-outer peripheral heat dissipation cavities.

23. The chip packaging structure according to claim 14, wherein, It further includes: An external radiator, which is located on the top surface of the support housing.

24. A method for forming a chip packaging structure, characterized in that, It includes the following steps: A heat dissipation cover is formed. The heat dissipation cover includes a support housing, a first partition board, and a coolant. The support housing includes a top surface and a bottom surface that are oppositely distributed. The area of the top surface of the support housing is larger than the area of the bottom surface of the support housing. A vacuum accommodation cavity is provided inside the support housing. The first partition board is located between the top surface and the bottom surface of the support housing. A plurality of the first partition boards are arranged at intervals and divide the vacuum accommodation cavity into an independent middle heat dissipation cavity and an outer peripheral heat dissipation cavity. The middle heat dissipation cavity is located in the middle of the vacuum accommodation cavity, and the outer peripheral heat dissipation cavity is distributed around the outer periphery of the middle heat dissipation cavity. The coolant is located in the middle heat dissipation cavity and the outer peripheral heat dissipation cavity; Mount the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip.

25. The method for forming the chip package structure according to claim 24, wherein, Before mounting the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip, the following steps are further included: Provide a chip, which includes a front surface and a back surface that are oppositely distributed; Mount the chip to the packaging substrate such that the front surface of the chip faces the packaging substrate.

26. The method for forming the chip package structure according to claim 25, wherein The heat dissipation cover further includes a support frame. The top end of the support frame is perpendicularly connected to the end of the top surface of the support housing. The support frame and the support housing enclose an inner cavity; The specific steps of mounting the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip include: mounting the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip, and mounting the support frame to the packaging substrate such that the chip is located in the inner cavity.

27. The method for forming the chip packaging structure according to claim 24, wherein After mounting the heat dissipation cover to the back surface of the chip in the direction from the bottom surface of the support housing towards the chip, the following steps are further included: Mount an external radiator to the top surface of the support housing.

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