CN117080185A

CN117080185A - Chip packaging structure, electronic equipment and chip heat dissipation cover

Info

Publication number: CN117080185A
Application number: CN202210507782.2A
Authority: CN
Inventors: 吕建标; 张弛; 卢俊; 郑见涛
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2022-05-10
Filing date: 2022-05-10
Publication date: 2023-11-17
Also published as: WO2023216717A1

Abstract

The embodiment of the application provides a chip packaging structure and electronic equipment with the same. Relates to the technical field of semiconductor heat dissipation. The novel chip heat dissipation cover can improve the heat dissipation effect of the chip. The chip packaging structure comprises: the heat dissipation device comprises a substrate, a chip arranged on the substrate and a heat dissipation cover which is arranged on the chip and can be fixedly connected with the substrate; the heat dissipation cover comprises a cavity, wherein the cavity is internally provided with cooling liquid, and the inner wall of the cavity is provided with a capillary structure; and at least one groove is formed in the first inner wall, opposite to the chip, of the cavity and close to the chip, and a capillary structure is filled in the at least one groove. The grooves filled with the capillary structures are formed in the heat dissipation cover, so that hot spots of the chip are restrained.

Description

Chip packaging structure, electronic equipment and chip heat dissipation cover

Technical Field

The present application relates to the field of semiconductor heat dissipation technologies, and in particular, to a chip package structure, an electronic device having the same, and a chip heat dissipation cover.

Background

With the evolution of silicon processing technology nodes, the problem of heat dissipation is becoming an important factor limiting the competitiveness of chips.

For example, fig. 1 shows a conventional technical means for dissipating heat from a chip. Specifically, after the chip 401 is integrated on the substrate 402, a heat dissipation cover (Lid) 403 is covered on a side of the chip 401 away from the substrate 402 and is fixedly connected to the substrate 402. That is, heat emitted from the chip 401 is dissipated by the heat dissipating cover 403. Typically, the heat sink cap 403 is made of metal, such as copper.

However, when the power of the chip 401 is relatively large, hot spots are easily formed in a local area of the chip 401, and thus, when the copper heat dissipating cover shown in fig. 1 is used, the heat dissipating effect is not obvious due to the high thermal resistance.

Therefore, the heat dissipation cover 403 shown in fig. 1 is removed, which is the current direction of heat evolution of the chip. That is, as in fig. 1, the heat-dissipating cover 403 may be removed, and the system heat sink 13 may be directly covered on the chip 401. In this way, the chip 401 is exposed, which causes problems such as a large risk of mechanical stress, and degradation of electromagnetic interference (electro magnetic interference, EMI).

Therefore, how to improve the heat dissipation effect of the chip is still a technical problem in the industry.

Disclosure of Invention

The application provides a chip packaging structure, electronic equipment with the chip packaging structure and a chip heat dissipation cover capable of dissipating heat of a chip. Through providing a novel chip heat dissipation lid, can promote the chip radiating effect, especially can restrain the chip and appear the hot spot.

In order to achieve the above purpose, the embodiment of the present application adopts the following technical scheme:

in one aspect, the present application provides a chip package structure. The chip package structure may be an insulated gate bipolar transistor (insulated gate bipolar transistor, IGBT) module, an optical module, or the like.

The chip packaging structure comprises: the heat dissipation device comprises a substrate, a chip arranged on the substrate and a heat dissipation cover which is arranged on the chip and can be fixedly connected with the substrate; the heat dissipation cover comprises a cavity, wherein the cavity is internally provided with cooling liquid, and the inner wall of the cavity is provided with a capillary structure; and at least one groove is formed in the first inner wall, opposite to the chip, of the cavity and close to the chip, and a capillary structure is filled in the at least one groove.

In the chip packaging structure provided by the application, the heat dissipation cover comprises a cavity with a cooling liquid and capillary structure, namely the heat dissipation cover belongs to a heat dissipation cover (vapor chamber lid, VCL) structure of a temperature equalization plate. The thermal gain of VCL structures is significantly improved over copper heat-dissipating covers, for example, when the chip power is 525W, the thermal gain of VCL structures may exceed 15 ℃ over metallic copper heat-dissipating covers. Therefore, the heat dissipation effect of the VCL structure on the chip is obviously improved.

In addition, in the VCL structure provided by the application, at least one groove recessed towards the chip direction is formed on the first inner wall opposite to the chip and close to the chip, and a capillary structure is filled in the at least one groove. For example, in the structural design that can be implemented, the opening position of the groove can be determined according to the hot spot position of the chip. So designed, the heat of the hot spot can be quickly transferred into the groove, the cooling liquid in the groove absorbs the heat and gasifies into steam, a large amount of heat energy is taken away, when the steam is diffused from a high-temperature area to a low-temperature area, the steam can be quickly condensed into liquid and release the heat energy when contacting with the inner wall with lower temperature, and then the condensed cooling liquid flows back into the groove by virtue of a capillary structure, so that a heat transfer cycle is completed. Under the continuous effect of a plurality of heat transfer circulation, can be continuous carry out the supplementary coolant liquid for in the recess to quick cooling to the hot spot, avoid the chip to appear the hot spot, thereby promote the working property of chip.

In addition, in the embodiment of the application, the grooves for accommodating the capillary structures are formed in the cavity so as to improve the heat dissipation effect, so that the size of the heat dissipation cover is not basically changed, for example, the thickness of the heat dissipation cover is not increased, and the large-size heat dissipation cover can be prevented from bringing larger mechanical stress risks to the chip.

In one possible way, the radial dimension of the groove increases gradually from the bottom surface of the groove to the opening of the groove.

By the design, the mechanical strength and rigidity of the heat dissipation cover are not affected by the fact that the groove is formed in the heat dissipation cover. In addition, from the technical aspect, the capillary structure can be filled in the groove more easily, so that the problem that larger gaps appear in the groove and the heat dissipation resistance is increased is avoided.

In one possible embodiment, the recess has a plurality of recesses, which enclose a ring shape.

For example, the plurality of grooves can be distributed along the periphery of the chip hot spot, so that heat can be dissipated from multiple directions to the chip hot spot, and the heat dissipation efficiency is improved.

In one possible implementation, the bottom surface of the recess is arcuate. For example, the bottom surface of the groove is recessed toward the chip.

The arc-shaped surface is used as the bottom surface of the groove, so that the mechanical stress in the groove can be avoided, and the mechanical strength of the heat dissipation cover is reduced.

In one possible implementation, the sides of the groove are arcuate.

By arranging the side surface of the groove as an arc surface, that is, by avoiding the structure that the groove contains a straight chamfer, the groove can be prevented from affecting the mechanical strength of the heat radiation cover when the arc surface is adopted.

In one possible way, the depth of the groove is less than or equal to the thickness of the capillary structure over the remaining area of the first inner wall.

Therefore, the thermal resistance caused by the capillary structure in the groove can be effectively reduced.

In one possible way, the surface of the capillary structure located on the groove is flush with the surface of the capillary structure on the remaining area of the first inner wall.

From the analysis of the heat radiation effect, the heat resistance of the whole heat radiation cover and the flow resistance of the cooling liquid are not increased; from manufacturing process analysis, it is also convenient to produce and manufacture the heat dissipation cover of this kind of structure, for example, can fill the capillary structure in the cavity, vibrate again to make the capillary structure be vibrated to the recess in, sinter again, just can make the surface of capillary structure on the recess flush with the surface of capillary structure in the other regions of first inner wall.

In one implementation, the heat dissipating cover further includes a plurality of support posts; the support columns are arranged between the first inner wall and the second inner wall at intervals, and the inner wall of the cavity opposite to the first inner wall is the second inner wall; at least one groove is arranged between two adjacent support columns.

Through setting up a plurality of support columns between first inner wall and second inner wall, can promote the intensity of heat dissipation lid. In this embodiment, a groove may be opened between two adjacent support columns.

In one possible implementation, the recess between two adjacent support columns may be one.

In one implementation, a plurality of grooves are disposed between two adjacent support columns, and the plurality of grooves are arranged between the two adjacent support columns at intervals.

The plurality of grooves filled with the capillary structure and the cooling liquid are adopted, so that the heat dissipation effect of the chip can be further improved.

In one manner that may be implemented, the plurality of support columns includes a first support column, a second support column, a third support column, and a fourth support column; the first support column, the second support column, the third support column and the fourth support column enclose a quadrilateral structure, and any side of the quadrilateral structure is provided with at least one groove.

When the chip works, hot spots of the chip can be located in quadrangular areas surrounded by the first support columns, the second support columns, the third support columns and the fourth support columns, and therefore heat of the hot spots of the chip can be quickly absorbed by the aid of the cooling liquid arranged in multiple directions by means of grooves filled with capillary structures and the cooling liquid at any side of the quadrangles, and the heat is gasified and evaporated.

In one implementation manner, in the quadrangle formed by the method, the number of grooves formed at the adjacent edges may be unequal or equal.

In one possible implementation manner, in the quadrangle formed in the foregoing manner, the radial dimensions of the grooves formed at the adjacent edges may be unequal, or may be equal; the groove depths of the grooves formed at the adjacent edges can be unequal or equal.

In one implementation, the grooves are part of a sphere, or the grooves are part of an ellipsoid.

In one implementation, the at least one groove includes a first groove and a second groove, the first groove having a groove depth that is not equal to the groove depth of the second groove.

In another aspect, the present application provides an electronic device, which may be a mobile terminal, such as a cell phone, tablet, or the like. The electronic equipment comprises a circuit board and the chip packaging structure in any implementation mode; the chip packaging structure is arranged on the circuit board and is electrically connected with the circuit board.

In the electronic device provided by the application, the chip packaging structure in any implementation manner is included, and in the chip packaging structure, the heat dissipation cover adopts a heat dissipation cover (vapor chamber lid, VCL) structure of a temperature equalization plate with grooves, for example, in the structural design which can be realized, the opening position of the grooves can be determined according to the hot spot position of the chip. By the design, heat of hot spots can be quickly conducted into the grooves, cooling liquid in the grooves absorbs the heat and is gasified into steam, a large amount of heat energy is taken away, the hot spots are quickly cooled, the hot spots of the chip are restrained, and therefore the working performance of the chip is improved.

In yet another aspect, the present application further provides a chip heat-dissipating cover that may be applied in a chip package structure to drive heat and cool a chip.

The chip heat dissipation cover comprises a cavity, wherein cooling liquid is contained in the cavity, a capillary structure is arranged on the inner wall of the cavity, at least one groove is formed in the first inner wall of the cavity, which is opposite to the chip, and the capillary structure is filled in the at least one groove.

In the implementation, the side of the cavity provided with the groove can be stacked on the chip, so that heat emitted by the chip can be quickly absorbed by cooling liquid in the groove, and the heat can be diffused to a low-temperature area for condensation, flows into the groove through the capillary action of the capillary structure, and continues the next heat transfer cycle.

In the implementation, the grooves are distributed around the hot spot of the chip, so that heat at the hot spot can be conducted into the grooves, and the heat can be quickly absorbed and diffused through cooling liquid in the grooves.

By the design, the capillary structure is easy to fill in the groove, the thermal resistance is reduced, and the manufacturing and the forming can be facilitated.

In one possible implementation, the bottom surface of the recess is arcuate.

In one implementation, the chip heat spreader lid further includes a plurality of support posts; the support columns are arranged between the first inner wall and the second inner wall at intervals, and the inner wall of the cavity opposite to the first inner wall is the second inner wall; at least one groove is arranged between two adjacent support columns.

Through setting up a plurality of support columns between first inner wall and second inner wall, can promote the intensity of heat dissipation lid. In this embodiment, a groove may be opened between two adjacent support columns. For example, a groove is formed between two adjacent support columns, or at least two grooves are formed.

Drawings

Fig. 1 is a schematic diagram of a structure for dissipating heat from a chip in the prior art;

fig. 2 is a partial circuit diagram of an electronic device according to an embodiment of the present application;

fig. 3 is a schematic diagram of a part of a structure of an electronic device according to an embodiment of the present application;

fig. 4 is a schematic structural diagram of a chip package structure according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a heat dissipating cover and a chip according to an embodiment of the present application;

fig. 6 is a schematic structural diagram of a heat dissipation cover for dissipating heat from a hot spot of a chip according to an embodiment of the present application;

fig. 7 is a schematic structural diagram illustrating a recess in a heat dissipating cover according to an embodiment of the present application;

fig. 8 is a schematic structural diagram of a recess in a heat dissipating cover according to another embodiment of the present application;

fig. 9 is a schematic structural diagram illustrating a recess in a heat dissipating cover according to another embodiment of the present application;

fig. 10 is a schematic structural diagram illustrating a recess in a heat dissipating cover according to another embodiment of the present application;

FIG. 11 is a schematic diagram illustrating a recess in a heat dissipating cover according to another embodiment of the present application;

FIG. 12 is a schematic diagram of a layout of a plurality of grooves according to an embodiment of the present application;

FIG. 13 is a schematic diagram of a layout of a plurality of grooves according to an embodiment of the present application;

fig. 14 is a schematic structural diagram of a heat dissipating cover and a chip according to an embodiment of the present application;

FIG. 15 is a schematic view of a structure including support posts and grooves according to an embodiment of the present application;

FIG. 16 is a schematic view of another embodiment of the present application including support posts and grooves;

FIG. 17 is a schematic view of another embodiment of the present application including support posts and grooves;

FIG. 18 is a schematic view of another embodiment of the present application including support posts and grooves;

FIG. 19 is a schematic view of a portion of a heat dissipating cover including a capillary structure;

fig. 20 is a schematic view of a part of a heat dissipating cover including a groove according to an embodiment of the present application;

fig. 21 is a schematic view of a portion of a structure of a heat dissipating cover including a capillary structure.

Reference numerals:

100-an electronic device;

200-CPU；

300-memory;

400-chip package structure;

11-a circuit board;

12-a first electrical connection structure;

13-a heat sink;

14-bolts;

401-chip;

402-substrate;

403-heat sink cap;

404-an adhesive layer;

405-TIM layer;

406-a second electrical connection structure;

4031-a cavity;

4032-capillary structure; 4032 a-capillary column;

4033-cooling liquid;

4034-groove;

4035-support column.

Detailed Description

The following embodiments of the present application are described below with reference to the drawings in the embodiments of the present application.

The technical solution of the present application may be applied to various electronic devices including chips, for example, fig. 2 is a circuit block diagram of an electronic device 100 provided in an embodiment of the present application, where the electronic device 100 may be a terminal device, for example, a mobile phone, a tablet computer, a smart band, or may be a personal computer (personal computer, PC), a server, a workstation, etc.

By way of example, and again as in fig. 2, the electronic device 100 may include a memory 300 and a central processing unit (central processing unit, CPU) 200, etc. The CPU200 may be electrically connected to the memory 300 through a signal line. For example, the memory may be an SRAM memory or other memory.

In the above electronic devices such as mobile phones, tablets, etc., the memory or the central processor may be present in the electronic device in the form of a chip package.

For example, fig. 3 is a block diagram of a chip package structure 400 according to an embodiment of the present application. The structure shown in fig. 3 includes a circuit board 11, such as a printed circuit board (printed circuit board, PCB), and a chip package structure 400 is disposed on the circuit board 11, and the chip package structure 400 is electrically connected to the circuit board 11 through a first electrical connection structure 12. By way of example, the chip package structure 400 may include an insulated gate bipolar transistor (insulated gate bipolar transistor, IGBT) module, an optical module, or the memory 300, cpu200, etc. referred to above.

In addition, other chips or other electronic devices may be disposed on the circuit board 11, so that the chip package structure 400 may implement signal interconnection with other chips or other electronic devices on the circuit board 11 through a wiring structure formed on the circuit board 11.

In an alternative embodiment, the first electrical connection structure 12 may be a Ball Grid Array (BGA), or may be a plurality of copper pillar bumps (copper pillar bump) arranged in an array.

The chips in the chip package structure 400, as well as other chips or electronic devices disposed on the wiring board 11, may emit heat during operation. In order to secure the operation performance of each electronic device including a chip, the structure shown in fig. 3 further includes a heat sink 13, and the heat sink 13 is covered on a side of the chip package structure 400 remote from the circuit board 11 and may be fixedly connected to the circuit board 11, for example, as shown in fig. 3, the heat sink 13 may be fixed to the circuit board 11 by a connection member, such as a bolt 14.

In the running process of the chip, heat is released, especially in a high-power chip, more heat is released, hot spots are easy to occur in the chip, for example, in an IGBT module, the power can reach several kilowatts or even tens of kilowatts because the IGBT module is a controlled voltage driven power semiconductor device consisting of a bipolar triode and an insulated gate field effect transistor, and the heat is larger. Therefore, in the chip package structure 400, not only a chip for realizing an electrical function is included, but also a heat dissipation structure for diffusing heat of the chip is required to ensure normal operation of the chip.

The embodiment of the application provides a chip packaging structure, which can improve the heat dissipation effect on a chip by changing a heat dissipation structure. Specific heat dissipation structures that can be implemented, and the heat dissipation principles are described below.

Fig. 4 is a schematic cross-sectional view of a chip package structure 400 according to an embodiment of the present application, where the chip package structure 400 includes: at least one chip 401, the chip 401 being integrated on a substrate 402. Fig. 4 illustrates the integration of a chip 401 on a substrate 402. Of course, FIG. 4 is merely an exemplary configuration, and more chips may be provided on the substrate 402.

The present application also relates to a chip 401 integrated on a substrate 402, which may be a wafer, or may be a package structure formed by packaging one or more wafers together.

In some alternative embodiments, as shown in fig. 4, any one of the chips 401 may be electrically connected to the substrate 402 through the second electrical connection structure 406, and a metal layer including a wiring structure is formed in the substrate 402. The substrate 402 establishes signal paths between chips or chips and other electronic devices through the wiring structure.

The chip 401, when disposed on the substrate 402, may employ Flip Chip Ball Grid Array (FCBGA) technology. In other package structures, wire bonding (wire bonding) techniques may also be used to place the chip on the substrate 402.

The substrate 402 may have various alternative structures, for example, the substrate 402 may be a package substrate (substrate), a rewiring layer (redistribution layer, RDL) substrate manufactured by a rewiring process, or an Interposer (Interposer). Of course, other configurations are also possible.

In addition, the chip package structure 400 further includes a heat dissipation cover (Lid) 403, where the heat dissipation cover 403 covers a side of the chip 401 away from the substrate 402 and may be fixedly connected to the substrate 402, for example, the heat dissipation cover 403 is adhered to the substrate 402 by an adhesive layer 404.

With continued reference to fig. 4, when the chip package structure 400 includes a heat spreader lid 403, the heat spreader lid 403 is coupled to the upper surface of the chip 401 by a layer 405 of thermal interface material (thermal interface material, TIM).

In this way, the heat emitted by the chip 401 is conducted to the heat dissipating cover 403 through the TIM layer 405, and the heat is diffused out through the heat dissipating cover 403 with a larger heat conducting area, so as to cool the chip 401 and ensure the normal operation of the chip.

Fig. 5 is a diagram illustrating a positional relationship among the heat spreader lid 403, the chip 401, and the TIM layer 405 according to an embodiment of the present application. In the heat sink cap 403 shown in fig. 5, a cavity 4031 is included, i.e., a cavity is provided in the housing of the heat sink cap 403. The inner wall of the cavity 4031 has a capillary structure 4032, and a cooling liquid 4033 is also contained in the cavity 4031.

The inner wall of the cavity 4031 has a capillary structure 4032, which can be understood that, as shown in fig. 5, the capillary structure 4032 is formed on a first inner wall M1 of the cavity 4031, which is close to the chip 401, and the capillary structure 4032 is also formed on a second inner wall M2 of the cavity 4031, which is far from the chip 401, and in addition, the capillary structure 4032 is also formed on a side inner wall M3 of the cavity 4031.

The cavity 4031 may be made of a metal material, such as copper, iron, or the like, or an alloy material.

The cooling liquid 4033 may include water, methanol, alcohol, acetone, and the like. It should be explained that: fig. 5 shows one state of the cooling liquid 4033, and during the heat dissipation of the heat dissipation cover 403, the cooling liquid 4033 is located at not only the first inner wall M1 but also the side inner wall M3 or the second inner wall M2 of the cavity 4031.

The capillary structure 4032 may be referred to as a wick structure or microstructure, and the wick structure may be a wire mesh, a micro groove, a fiber filament, or the like, or a sintered metal powder wick, or a combination of several structures.

When heat is conducted from the heat source chip 401 to the heat dissipating cover 403, the cooling liquid 4033 in the cavity 4031 is heated in the environment to generate a vaporization phenomenon of the cooling liquid, at this time, the cooling liquid 4033 absorbs heat energy and expands rapidly, the whole cavity 4031 is filled with the gas phase cooling liquid 4033 rapidly, and a condensation phenomenon is generated when the gas phase working medium contacts a relatively cold area. The heat accumulated during evaporation is released by the phenomenon of condensation. And, the condensed cooling liquid returns to the evaporation heat source through the capillary structure 4032, and this operation is repeated in the inner periphery of the cavity 4031, so as to cool the chip 401.

With continued reference to fig. 5, in the heat dissipating cover 403, at least one groove 4034 recessed toward the chip 401 is formed on a partial area of the first inner wall M1 of the cavity 4031, and the groove 4034 is also filled with the capillary structure 4032, for example, as shown in fig. 5, the groove 4034 may be filled with the capillary structure 4032, and for example, the capillary structure 4032 may be formed on the bottom and the side wall of the groove 4034.

Fig. 6 is a structural diagram of the heat dissipation cover 403 according to the present application applied to heat dissipation of the chip 401, and fig. 6 shows a partial structure of the heat dissipation cover 403 in a simplified manner. When the chip 401 is in operation, hot spots easily occur in a part of the area, as shown in fig. 6, three hot spots occur in the chip 401 are exemplarily shown, and then when the groove 4034 is formed in the first inner wall M1 of the cavity 4031, the groove 4034 may be arranged close to the hot spot area of the chip 401. By arranging the groove 4034 with the capillary structure 4032 close to the hot spot, the heat conduction path of the hot spot can be shortened, and more heat emitted from the hot spot can be quickly absorbed by the cooling liquid 4033 flowing into the groove 4034, so that the temperature of the hot spot can be quickly reduced.

As can be understood from the heat dissipation process of the heat dissipation cover 403 shown in fig. 6 for the heat dissipation of the chip 401, part of the heat at the heat spot is conducted into the groove 4034 through the TIM layer 405 and the outer shell of the heat dissipation cover 403, the cooling liquid (such as water) in the groove 4034 can quickly absorb the heat and gasify into vapor, so as to take away a large amount of heat energy, the vapor is diffused from the high temperature region to the low temperature region, and when the vapor contacts the inner wall with lower temperature, the vapor can quickly condense into liquid and release the heat energy. The condensed cooling liquid flows back into the groove 4034 by capillary action of the capillary structure 4032 to complete a heat transfer cycle, so that a two-phase circulation system with water and water vapor is formed.

In addition, with continued reference to fig. 6, because the thickness (along the dimension perpendicular to the chip 401) of the capillary structure 4032 at the groove 4034 of the first inner wall M1 is thicker than the thickness of the other capillary structures 4032 without the groove 4034, the capillary structures 4032 in the cavity 4031 are not substantially burned out due to the hot spot, so that the service performance of the heat dissipating cover can be ensured.

By adopting the heat dissipation mode of opening the groove 4034 in the partial region of the first inner wall M1 and filling the capillary structure 4032 in the groove as shown in fig. 6, compared with the heat dissipation mode of increasing the capillary structure 4032 on the whole first inner wall M1, the heat resistance of the non-hot spot region and the flow resistance of the cold liquid are reduced, so that the heat dissipation effect of the non-hot spot region can be further improved.

Based on the above description of the structure of the heat dissipating cover 403 and the heat dissipating principle, it can be seen that the heat dissipating cover 403 is a heat dissipating cover (vapor chamber lid, VCL) structure of a temperature equalizing plate. When the VCL structure provided by the embodiment of the application is used for radiating the chip, the radiating efficiency of the chip can be obviously improved based on the grooves filled with the capillary structure and the cooling liquid, and the occurrence of hot spots of the chip is restrained.

The structure, arrangement position, number, etc. that can be achieved by the grooves 4034 according to the embodiment of the present application are described below.

Fig. 7 is a partial block diagram of a heat dissipating cover with a recess 4034 according to an embodiment of the present application. In which the radial dimension D of the groove 4034 gradually increases from the bottom surface of the groove 4034 to the opening direction, i.e., along the direction P shown in fig. 7. That is, the closer to the bottom surface of the groove 4034, the smaller the radial dimension D, and the closer to the opening of the groove 4034, the larger the radial dimension D.

If the groove 4034 with the structure shown in fig. 7 is adopted, not only the implementation is easy from the manufacturing process, but also when the capillary structure is filled in the groove 4034 with the structure, a larger gap between the capillary structure and the groove and/or between particles of the capillary structure can be effectively avoided, and when the larger gap exists, the thermal resistance can be correspondingly increased, so that the heat dissipation effect is affected. Therefore, when the groove 4034 with gradually changing radial dimension of the structure shown in fig. 7 is adopted, the thermal resistance can be effectively reduced, and the heat dissipation effect can be improved.

Referring to fig. 7, the bottom surface S of the groove 4034 is an arc surface, for example, the bottom surface S is an arc surface recessed toward the chip direction, that is, the bottom surface of the groove 4034 may be a curved surface recessed toward the outer wall surface of the heat dissipating cover. The arc surface can be a wave surface formed by a plurality of curved surfaces in an abutting mode, and can also be a spherical surface, an ellipsoidal surface and the like. The bottom surface of the arc-shaped surface can reduce the generated mechanical stress.

In some embodiments, the sides of the groove 4034 may also be arcuate as shown in fig. 7. By adopting the side structure of the cambered surface, the mechanical strength of the heat radiation cover 403 can be greatly influenced by the groove 4034.

Fig. 9 and 10 are views along the N direction shown in fig. 7. For example, the recess 4034 may be an ellipsoidal structure with an elliptical cross-section; for another example, the recess 4034 may be a sphere with a circular cross-section. Of course, other configurations are also possible.

Fig. 8 shows the remaining possible structure of the groove 4034, and in fig. 8, the cross section of the groove 4034 may be triangular or may be trapezoidal. Compared with the groove with the bottom surface with the straight edges and corners in the example of fig. 8, the groove shown in fig. 7 can avoid the phenomenon that the mechanical strength of the heat dissipation cover is affected because the groove exists in the heat dissipation cover when the bottom surface of the groove adopts an arc-shaped surface.

To further enhance the heat dissipation effect, the groove 4034 may have a plurality, for example, in fig. 7, 9 and 10, a case including a first groove and a second groove is exemplarily shown. Of course, more grooves are also possible.

When the grooves 4034 of the present application are plural, the depths H1 of the plural grooves 4034 may be the same or partially the same or different as shown in fig. 7.

Fig. 11 is a partial block diagram of a heat sink cap 403 including a recess 4034 in accordance with an embodiment of the present application. Wherein the depth H1 of the groove 4034 may be less than or equal to the thickness H2 of the capillary structure 4032 on the remaining area of the first inner wall M1. The remaining area of the first inner wall M1 may be regarded as an area of the first inner wall M1 where the groove 4034 is not provided.

If the depth H1 of the groove 4034 shown in fig. 11 is smaller than or equal to the thickness H2 of the capillary structure 4032 on the remaining area of the first inner wall M1, that is, the thickness of the capillary structure 4032 filled in the groove 4034 is smaller than the thickness of the capillary structure 4032 on the remaining area, heat at the hot spot can be ensured to be quickly absorbed by the cooling liquid in the groove. Because the heat resistance is increased when the thickness of the capillary structure 4032 is larger, the heat dissipation effect is affected, and when the thickness of the capillary structure 4032 is smaller, the phenomenon that the capillary structure 4032 is burned out easily occurs. Therefore, the depth H1 of the groove 4034 can be defined to be smaller than or equal to the thickness H2 of the capillary structure 4032 on the remaining area of the first inner wall M1, i.e., the heat resistance can be suppressed, and the risk of the capillary structure being burned off can be eliminated.

Referring again to fig. 11, the surface T1 of the capillary structure 4032 on the groove 4034 is flush with the surface T2 of the capillary structure 4032 on the remaining area of the first inner wall M1.

From the technical point of view, when the structure shown in fig. 11 is manufactured, the first inner wall M1 may be first provided with the groove 4034, then the cavity 4031 is filled with the capillary structure 4032, and then vibration is performed to make the capillary structure 4032 shake into the groove 4034, and then sintering is performed to make the surface of the capillary structure on the groove flush with the surface of the capillary structure in the rest area of the first inner wall.

In some embodiments, when there are multiple grooves 4034, these multiple grooves 4034 have a variety of arrangements that can be achieved.

For example, fig. 12 illustrates one of a plurality of grooves 4034 in accordance with an embodiment of the present application. That is, the plurality of grooves 4034 are arranged in a straight line, for example, the plurality of grooves 4034 are arranged in parallel with the side length of the chip.

For another example, fig. 13 shows another arrangement of a plurality of grooves 4034 according to an embodiment of the present application. I.e. a plurality of grooves 4034 are encircling. For example, the plurality of grooves 4034 may be wrapped around the periphery of the chip.

In order to increase the mechanical strength of the heat dissipating cover 403, in some implementation structures, see fig. 14, fig. 14 is a structural diagram of another heat dissipating cover 403 according to an embodiment of the present application, where the heat dissipating cover 403 includes not only the cavity 4031, the cooling liquid 4033, and the capillary structure 4032 shown in the above heat dissipating cover 403, but also the grooves 4034 filled with the capillary structure 4032 and the cooling liquid 4033, and further includes a plurality of support columns 4035. Wherein, a plurality of support columns 4035 are disposed within the cavity 4031, i.e., supported between the first inner wall M1 and the second inner wall M2. The strength of the heat dissipating cover 403 can be enhanced by using a plurality of support columns 4035 arranged in the cavity 4031 at intervals, so as to prolong the service life of the heat dissipating cover 403.

In some possible configurations, the support columns 4035 may be cylindrical, rectangular, or other shapes.

In some embodiments, the support posts 4035 can be integrally formed with the cavity 4031; alternatively, in other embodiments, the support posts 4035 are fixedly attached to the cavity 4031 by an attachment structure, such as welding.

In the case of opening the groove 4034, there are various cases of the positional relationship of the groove 4034 and the support column 4035, and several examples are given below, and the following description is specific.

Fig. 15 illustrates a schematic view of one of the structures of the groove 4034 and the support column 4035. A groove 4034 may be formed between two adjacent support columns 4035, and the shapes of the grooves 4034 are the same, and the sizes (including radial sizes) of the grooves 4034 are the same, for example, the grooves 4034 are all hemispherical structures.

Fig. 16 shows an exemplary illustration of a further structure of the recess 4034 and the support column 4035. Unlike fig. 15 described above, in this embodiment, a plurality of grooves 4034 are provided between two adjacent support columns 4035. And the application is not limited to the number of grooves.

Also, in fig. 16, the plurality of grooves 4034 are all the same in shape, and the plurality of grooves 4034 are all the same in size (including radial size), for example, the plurality of grooves 4034 are all hemispherical in structure.

Fig. 17 shows an exemplary illustration of a further structure of the recess 4034 and the support column 4035. In this embodiment, a groove 4034 is formed between a portion of two adjacent support columns 4035, and a plurality of grooves 4034 are formed between a portion of two adjacent support columns 4035. If there are multiple grooves 4034 between two adjacent support columns 4035, then the multiple grooves 4034 are spaced between the two support columns 4035, e.g., the multiple grooves 4034 are equally spaced.

In addition, in fig. 17, the plurality of grooves 4034 are all the same in shape, for example, the plurality of grooves 4034 are all hemispherical structures.

Fig. 18 shows an exemplary illustration of a further structure of the recess 4034 and the support column 4035. The same as in the above embodiment is: a groove 4034 is formed between part of two adjacent support columns 4035, and a plurality of grooves 4034 are formed between part of two adjacent support columns 4035. The differences are: one part of the grooves 4034 are hemispherical grooves, and the other part of the grooves 4034 are semi-ellipsoidal grooves.

It should be explained that: the hemispherical recess to which the present application relates may be understood as half, or nearly half, of the spherical recess. Similarly, a semi-ellipsoidal recess can be understood to be half, or nearly half, of an ellipsoidal recess.

In some embodiments, the radial dimension of the groove 4034 may be less than or equal to the radial dimension of the support post 4035, so designed as not to substantially affect the mechanical strength of the heat dissipating cover. For example, when the radial dimension of the support column 4034 is 1mm to 3mm, the opening of the groove 4034 may be designed to be 1mm to 3mm. In this way, the provision of the larger-sized recess 4034 can be avoided from affecting the mechanical strength of the heat dissipating cover.

Referring to fig. 15 to fig. 18 together, the black squares in fig. 15 to fig. 18 illustrate hot spots of the chips, and in some embodiments, the hot spots may be located in a region surrounded by a plurality of support columns, for example, four support columns surround a quadrangle in the drawing, and the orthographic projection of the hot spots on the heat dissipation cover is located in the quadrangle, so that a groove 4034 may be formed between two support columns 4035 with any side length of the quadrangle to absorb heat of the hot spots from multiple directions, thereby improving heat dissipation efficiency of the hot spots.

In other possible structures, with continued reference to fig. 15 to 18, for example, the orthographic projection of the hot spot on the heat dissipating cover 403 is the first area, and the groove 4034 is disposed as much as possible on the periphery of the first area, so that gaps formed between the capillary structures in the groove 4034 are avoided to raise the thermal resistance, and the heat dissipating efficiency is affected.

Fig. 19 is a partial structural view of a heat dissipating cover formed with a capillary structure 4032. In this structure, no groove is provided. In order to improve the heat dissipation effect, the thickness of the capillary structure 4032 can be increased to rapidly cool the chip.

Fig. 20 is a partial block diagram of a heat dissipating cover with a groove 4034 according to an embodiment of the present application. Compared with the above-mentioned figure 19, the partial area in the heat-dissipating cover is provided with grooves, and the thickness of the capillary structure 4032 at the position where the grooves are located is larger than that of the capillary structures 4032 at other areas, so that the heat resistance of other areas is not increased on the basis of improving the heat-dissipating efficiency.

Fig. 21 is a partial structural view showing a heat dissipating cover formed with a capillary structure 4032 and capillary columns 4032a. In this structure, in order to enhance the heat dissipation effect of the hot spot, capillary columns 4032a may be formed on the capillary structure 4032. However, in this implementation, in comparison with the structure shown in fig. 20 provided in the embodiment of the present application, in the process fabrication that can be implemented, the formation of the capillary column 4032a is easier to implement than the formation of the groove 4034, and the capillary column 4032a is easily broken.

The embodiment of the application also provides a preparation method for manufacturing the heat dissipation cover 403, which may include:

a plurality of support posts 4035 and at least one groove 4034 are formed in the first plate using a mold.

When the groove 4034 is formed, the position of the groove 4034 can be determined according to the hot spot position of the chip.

And, the number of grooves 4034 may be determined according to the number of hot spots of the chip.

The capillary structure 4032 is filled such that between every adjacent two support columns 4035, and within each recess 4034, the capillary structure 4032 is filled.

During the filling of the capillary structure 4032 described above, the first plate may be vibrated so that the capillary structure 4032 is uniformly filled within the recess 4034 and between two adjacent support columns 4035. And, a capillary structure 4032 is formed on the side wall of the first plate.

The first plate filled with the capillary structure 4032 is placed in a sintering device, and the capillary structure 4032 is sintered so that the capillary structure 4032 is fixed on the first plate.

Vacuumizing and filling cooling liquid; in addition, a second plate with a capillary structure is arranged on the inner wall surface, so that the second plate is fixedly connected with the first plate, and the heat dissipation cover is formed.

In the description of the present specification, a particular feature, structure, material, or characteristic may be combined in any suitable manner in one or more embodiments or examples.

The foregoing is merely illustrative of the present application, and the present application is not limited thereto, and any person skilled in the art will readily recognize that variations or substitutions are within the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A chip package structure, comprising:

a substrate;

a chip disposed on the substrate;

the heat dissipation cover is arranged on the chip;

the heat dissipation cover comprises a cavity, wherein cooling liquid is contained in the cavity, and a capillary structure is arranged on the inner wall of the cavity;

and the first inner wall of the cavity, which is opposite to the chip and is close to the chip, is provided with at least one groove, and the capillary structure is filled in the at least one groove.

2. The chip package structure of claim 1, wherein the plurality of grooves are formed in a ring shape.

3. The chip packaging structure according to claim 1 or 2, wherein a radial dimension of the recess gradually increases from a bottom surface of the recess to an opening of the recess.

4. The chip package structure of any one of claims 1-3, wherein a bottom surface of the recess is an arcuate surface.

5. The chip package structure of any one of claims 1-4, wherein a depth of the groove is less than or equal to a thickness of the capillary structure over a remaining area of the first inner wall.

6. The chip package structure according to any one of claims 1 to 5, wherein a surface of the capillary structure located on the recess is flush with a surface of the capillary structure on the remaining area of the first inner wall.

7. The chip package structure according to any one of claims 1 to 6, wherein the heat dissipation cover further comprises: a plurality of support columns;

the support columns are arranged between the first inner wall and the second inner wall at intervals, and the inner wall of the cavity opposite to the first inner wall is the second inner wall;

at least one groove is arranged between two adjacent support columns.

8. The chip packaging structure according to claim 7, wherein the plurality of support columns includes a first support column, a second support column, a third support column, and a fourth support column;

the first support column, the second support column, the third support column and the fourth support column enclose a quadrilateral structure, and any side of the quadrilateral structure is provided with at least one groove.

9. An electronic device, comprising:

a circuit board;

the chip package structure of any one of claims 1-8;

the chip packaging structure is arranged on the circuit board.

10. A chip heat sink cap, comprising:

a cavity;

the cooling liquid and the capillary structure are contained in the cavity, and the capillary structure is arranged on the inner wall of the cavity;

at least one groove is formed in the first inner wall, opposite to the chip, of the cavity, and the capillary structure is filled in the at least one groove.

11. The die attach cover of claim 10, wherein said recess has a plurality of said recesses, a plurality of said recesses surrounding a ring shape.

12. The die attach cover of claim 10 or 11, wherein the radial dimension of the recess increases gradually from the bottom surface of the recess to the opening of the recess.

13. The die attach cover of any of claims 10-12, wherein a bottom surface of the recess is arcuate.

14. The die heat sink cap of any one of claims 10-13, wherein the depth of the recess is less than or equal to the thickness of the capillary structure over the remaining area of the first inner wall.

15. The die heat sink cap of any one of claims 10-14, wherein a surface of the capillary structure on the recess is flush with a surface of the capillary structure on the remaining area of the first inner wall.

16. The die heat sink cover of any of claims 10-15, further comprising: a plurality of support columns;

at least one groove is arranged between two adjacent support columns.

17. The chip heat spreader lid of claim 16, wherein the plurality of support posts comprises a first support post, a second support post, a third support post, and a fourth support post;