Packaging structure and preparation method thereof

Abstract

The present invention provides a packaging structure and a preparation method thereof, wherein the packaging structure comprises a main circuit board, an antenna board, and at least two main function chips electrically connected to the main circuit board; at least two of the main function chips are spaced apart on the front side of the main circuit board, and the antenna board is connected to a side of the two spaced apart main function chips away from the main circuit board; the packaging structure also comprises a heat dissipation cover connected to a side of the at least two main function chips away from the main circuit board, and the heat dissipation cover has a receiving cavity for receiving the antenna board; at least two of the main function chips do not occupy the space on the back side of the main circuit board, thus reducing the planar size of the packaging structure and facilitating the connection between the heat dissipation cover and the main function chips, that is, facilitating the design of a corresponding heat dissipation structure for dissipating heat from the main function chips, and having a simple structure.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor packaging, and in particular to a packaging structure that is beneficial to the heat dissipation of a main function chip and a preparation method thereof. Background Art

[0002] In recent years, with the advent of the 5G high-speed communication era, millimeter wave frequency band antenna transmission will become the mainstream transmission technology in the 5G era. Millimeter wave frequency band transmission is not suitable for long-distance transmission. The longer the path, the greater the signal attenuation. The newer Aip technology is an integrated structure of IC+packaged antenna, which can achieve high gain through antenna arrays.

[0003] At the same time, the wavelength of the millimeter wave band is extremely short, requiring higher processing accuracy to meet the requirements of stable electrical performance. Any error in processing accuracy may lead to impedance mismatch and then signal reflection. Traditional PCB processing technology can no longer meet the processing accuracy requirements of the millimeter wave band. Therefore, higher processing accuracy such as Figure 1 The dual-substrate packaging structure shown in will become the main processing method in the millimeter wave frequency band.

[0004] like Figure 1 As shown, the dual-substrate packaging structure mainly stacks the main circuit board 1' and the antenna board 3', and at the same time, electrically connects the chip 2' to the lower side of the main circuit board, wherein the main circuit board is located on the lower side, and the antenna board is located on the upper side. The main circuit board and the antenna board maintain a consistent cavity height Z and alignment in the XY direction. The dual-substrate packaging structure meets the processing accuracy requirements and has stable structural characteristics. However, the heat dissipation solution of the chip in this dual-substrate packaging structure has high requirements for the main circuit board, and the heat dissipation connection between the chip and the main circuit board is affected by the height and distribution of the solder balls on the lower side of the main circuit board. The technical difficulty is high and the cost is high. At the same time, the relative volume of this dual-substrate packaging structure is large.

[0005] In view of this, it is necessary to provide a new packaging structure and a preparation method thereof to solve the above problems. Summary of the invention

[0006] The object of the present invention is to provide a packaging structure which is beneficial to the heat dissipation of a main function chip and a preparation method thereof.

[0007] To achieve the above-mentioned invention objectives, the present invention adopts the following technical solutions: a packaging structure, including a main circuit board, an antenna board, and at least two main function chips electrically connected to the main circuit board; at least two of the main function chips are spaced apart on the front of the main circuit board, and the antenna board is connected to a side of the two spaced apart main function chips away from the main circuit board; the packaging structure also includes a heat dissipation cover connected to a side of the at least two main function chips away from the main circuit board, and the heat dissipation cover has a receiving cavity for receiving the antenna board.

[0008] As a further improved technical solution of the present invention, the antenna board is provided with metal solder balls or metal columns for connecting to the main function chip.

[0009] As a further improved technical solution of the present invention, there is an insulating material between the antenna board and the main function chip, which is coated on the outside of the metal solder ball or the metal column.

[0010] As a further improved technical solution of the present invention, an adhesive layer for connecting with the main function chip is provided on the antenna board.

[0011] As a further improved technical solution of the present invention, the adhesive layer is a resin adhesive layer or a bubble film layer.

[0012] As a further improved technical solution of the present invention, a first solder ball for electrically connecting to the main circuit board is provided on the main function chip, and an insulating material covering the first solder ball is provided between the main function chip and the main circuit board.

[0013] As a further improved technical solution of the present invention, the main function chip has an antenna board connection part and a heat dissipation cover connection part on the side away from the main circuit board, and the antenna board connection part and / or the heat dissipation cover connection part have a metal plating layer.

[0014] As a further improved technical solution of the present invention, the heat dissipation cover also includes a connection platform connected to the main circuit board.

[0015] As a further improved technical solution of the present invention, a hollow portion is provided on the heat dissipation cover at a position corresponding to the antenna plate.

[0016] To achieve the above-mentioned object of the invention, the present invention further provides a method for preparing a packaging structure, comprising the following steps:

[0017] S1: at least two main function chips are arranged at intervals on the front side of the main circuit board;

[0018] S2: Connecting the antenna board to one side of the two main function chips spaced apart from the main circuit board;

[0019] S3: Connecting the heat dissipation cover to the at least two main function chips.

[0020] As a further improved technical solution of the present invention, the method for preparing the packaging structure further includes the following step located between step S1 and step S2: filling insulating material between the main function chip and the main circuit board.

[0021] As a further improved technical solution of the present invention, the antenna board is connected to the main function chip through metal solder balls or metal columns; the preparation method of the packaging structure also includes the following step located between steps S2 and S3: filling insulating material between the antenna board and the main function chip.

[0022] As a further improved technical solution of the present invention, the antenna board is connected to the main function chip through an adhesive layer.

[0023] As a further improved technical solution of the present invention, the heat dissipation cover also includes a connection platform connected to the main circuit board.

[0024] The beneficial effects of the present invention are as follows: the packaging structure of the present invention, by arranging at least two of the main function chips at intervals on the front side of the main circuit board, at least two of the main function chips do not occupy the space on the back side of the main circuit board, thereby reducing the planar size of the packaging structure, improving the utilization rate of the substrate, and facilitating the connection between the heat dissipation cover and the main function chip, that is, facilitating the design of a corresponding heat dissipation structure for dissipating heat from the main function chip, and having a simple structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural schematic diagram of a packaging structure in the prior art.

[0026] Figure 2 Schematic diagram of the packaging structure in the first embodiment of the present invention.

[0027] Figure 3 Schematic diagram of the structure of the antenna board in the first embodiment of the present invention.

[0028] Figure 4 Schematic diagram of the structure of the antenna board in the second embodiment of the present invention.

[0029] Figure 5 4 is a schematic structural diagram of an antenna board in a third embodiment of the present invention.

[0030] Figure 6 It is a schematic structural diagram of a packaging structure in another specific embodiment of the present invention.

[0031] Figure 7 It is a structural schematic diagram of the heat dissipation cover in the present invention.

[0032] Figure 8(a)-Figure 8(e) It is a step diagram of the method for preparing the packaging structure in the present invention. DETAILED DESCRIPTION

[0033] The present invention will be described in detail below in conjunction with the various embodiments shown in the accompanying drawings. Figure 2 As shown in FIG8 , it is a preferred embodiment of the present invention. However, it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformation or replacement of functions, methods, or structures made by ordinary technicians in the field according to these embodiments shall fall within the protection scope of the present invention.

[0034] Please refer to Figures 2 to 3 As shown, the package structure 100 in the first embodiment of the present invention comprises a main circuit board 1, at least two main function chips 2 arranged on the front of the main circuit board 1 and electrically connected to the main circuit board 1, an antenna board 3 located on the side of the at least two main function chips 2 away from the main circuit board 1, and a heat dissipation cover 4 connected to the at least two main function chips 2, wherein the heat dissipation cover 4 has a receiving cavity 41 for receiving the antenna board 3. After the heat dissipation cover 4 is connected to the main function chip 2, the antenna board 3 is located in the receiving cavity 41. At the same time, the heat dissipation cover 4 is in direct contact with the main function chip 2 to conduct the heat generated by the main function chip 2. In the present invention, at least two main function chips 2 in the package structure 100 are arranged on the front of the main circuit board 1, and at least two main function chips 2 do not occupy the space on the back of the main circuit board 1, which can reduce the plane size of the package structure 100 and facilitate the connection between the heat dissipation cover 4 and the main function chip 2, that is, it is convenient to design a corresponding heat dissipation structure for dissipating heat from the main function chip 2, and the structure is simple.

[0035] Preferably, all the main function chips 2 in the packaging structure 100 are arranged on the front side of the main circuit board 1, so that the main function chips 2 do not occupy the space on the back side of the main circuit board 1, the planar size of the packaging structure 100 can be reduced, and it is easy to design a corresponding heat dissipation structure for dissipating the heat of the main function chips 2, and the structure is simple.

[0036] It is understandable that when the packaging structure 100 is applied, an external heat dissipation structure that cooperates with the heat dissipation cover 4 will be set to output heat. The external heat dissipation structure can adopt an existing air cooling structure, water cooling structure or other existing heat dissipation structure, which will not be repeated here.

[0037] It is understandable that, in addition to the at least two main function chips 2 mentioned above, the package structure 100 also includes other chips, and the arrangement positions of other chips can be arranged separately according to specific circumstances, and are not particularly limited in the present invention. At the same time, during the use of the package structure 100, the main function chip 2 generates more heat than other chips, so a heat dissipation cover 4 is required to output the heat of the main function chip 2.

[0038] Specifically, at least two of the main function chips 2 are spaced apart on the front of the main circuit board 1. When three or more main function chips 2 are spaced apart on the front of the main circuit board 1, at least two main function chips 2 are spaced apart. In this embodiment, the example of two main function chips 2 spaced apart on the front of the main circuit board 1 is used for specific explanation. Of course, it is not limited to this.

[0039] The antenna board 3 is connected to the side of the two main function chips 2 that are spaced apart from the main circuit board 1, that is, in an embodiment in which three or more main function chips 2 are spaced apart on the front side of the main circuit board 1, the antenna board 3 is connected to two adjacent main function chips 2 that are spaced apart.

[0040] Specifically, the two main function chips 2 provided with the antenna board 3 have an antenna board 3 connection part and a heat dissipation cover 4 connection part on the side away from the main circuit board 1, that is, the main function chip 2 provided with the antenna board 3 can also achieve heat dissipation by connecting with the heat dissipation cover 4. It can be understood that the other main function chips 2 provided on the front side of the main circuit board 1 can be directly connected with the heat dissipation cover 4 to achieve heat dissipation.

[0041] It can be understood that the connection part of the heat dissipation cover 4 on one of the two main function chips 2 of the antenna board 3 is located on the side of the connection part of the antenna board 3 away from the other main function chip 2. After the antenna board 3 is connected to the connection part of the antenna board 3, the antenna board 3, the two main function chips 2 and the main circuit board 1 together form a cavity.

[0042] Furthermore, the main function chip 2 is electrically connected to the main circuit board 1 in a flip-chip manner.

[0043] Specifically, a first solder ball 21 is provided on the main function chip 2, and the main function chip 2 and the main circuit board 1 are soldered together through the first solder ball 21 to achieve a fixed connection and electrical connection between the main function chip 2 and the main circuit board 1.

[0044] Furthermore, there is an insulating material coated on the outside of the first solder ball 21 between the main function chip 2 and the main circuit board 1 to prevent the first solder ball 21 from contacting other circuits on the main circuit board 1 and causing a short circuit. At the same time, the insulating material is coated on the periphery of the first solder ball 21, which can position the first solder ball 21 and prevent the first solder ball 21 from contacting with the outside air and oxidizing.

[0045] Specifically, the insulating material fills the gap between the main function chip 2 and the main circuit board 1 .

[0046] Please refer to Figure 3 As shown, in the first embodiment of the present invention, the antenna board 3 is provided with a metal solder ball 31 for connecting with the main function chip 2 , and the antenna board 3 and the main function chip 2 are welded together through the metal solder ball 31 .

[0047] Furthermore, the connecting portion of the antenna board 3 on the main function chip 2 has a metal plating layer 22 to facilitate welding with the metal solder ball 31; of course, this is not limited to this. It can be understood that a connecting terminal corresponding to the metal solder ball 31 can also be set on the connecting portion of the antenna board 3 to achieve a fixed connection between the antenna board 3 and the main function chip 2 through welding between the metal solder ball 31 and the connecting terminal.

[0048] Specifically, the metal plating layer 22 may be a gold plating layer, but is not limited thereto.

[0049] Furthermore, an insulating material is filled between the antenna board 3 and the main function chip 2 , and the insulating material is coated on the periphery of the metal solder ball 31 , which can position the metal solder ball 31 and prevent the metal solder ball 31 from being oxidized by contact with the outside air.

[0050] Please refer to Figure 4 As shown, it is the second embodiment of the present invention. The difference between the second embodiment of the present invention and the first embodiment is that the antenna board 3 is provided with a metal bump 32 for connecting to the main function chip 2. It can be understood that the main function chip 2 is additionally provided with a connecting terminal connected to the metal bump 32, so that the antenna board 3 and the main function chip 2 can be welded together through the metal bump 32.

[0051] The second embodiment of the present invention is the same as the first embodiment except for the above differences, and will not be described in detail here.

[0052] Please refer to Figure 5As shown, it is the third embodiment of the present invention. The difference between this embodiment and the first embodiment is that the metal solder ball 31 is not arranged on the antenna board 3, but an adhesive layer 33 for connecting with the main function chip 2 is arranged on the antenna board 3. The connection between the antenna board 3 and the main function chip 2 is achieved through the adhesive layer 33. The structure is simple and the mounting of the antenna board 3 is convenient.

[0053] Specifically, the adhesive layer 33 may be an adhesive layer or a thin film connecting layer, such as a resin adhesive layer or a bubble film layer, but of course, it is not limited thereto.

[0054] It can be understood that, in the third embodiment, the metal plating layer 22 may or may not be provided on the connecting portion of the antenna plate 3 .

[0055] The third embodiment of the present invention is the same as the first embodiment except for the above differences, and will not be described in detail here.

[0056] Furthermore, the connecting portion of the heat dissipation cover 4 is provided with a metal plating layer 22, which, on the one hand, facilitates the heat conduction of the main function chip 2 and enhances the heat dissipation effect of the heat dissipation cover 4; on the other hand, facilitates the fixed connection between the heat dissipation cover 4 and the connecting portion of the heat dissipation cover 4 by welding.

[0057] It is understandable that when installing the heat dissipation cover 4, hot pressing welding, reflow soldering or adhesive material can be used to achieve the connection between the heat dissipation cover 4 and the connecting part of the heat dissipation cover 4. At the same time, the heat dissipation cover 4 and the connecting part of the heat dissipation cover 4 can be directly connected or indirectly connected through thermal conductive materials.

[0058] Furthermore, a hollow portion 42 is provided on the heat dissipation cover 4 at a position corresponding to the antenna board 3 , so as to prevent the heat dissipation cover 4 from affecting signal transmission of the antenna board 3 .

[0059] Specifically, positions on the heat dissipation cover 4 corresponding to the antenna plate 3 are all configured as hollow portions 42 .

[0060] For further information, see Figure 6 As shown, in another specific embodiment of the present invention, the heat dissipation cover 4 further includes a connection platform 43 connected to the main circuit board 1 to achieve packaging of the main circuit board 1 .

[0061] It is understandable that there is an adhesive material, such as glue or tin, between the end of the connecting platform 43 facing the main circuit board 1 and the main circuit board 1 to achieve a fixed connection between the connecting platform 43 and the main circuit board 1.

[0062] For further information, see Figure 8(a)-Figure 8(e)As shown, the present invention further provides a method for preparing a packaging structure 100 , and the packaging structure 100 is the packaging structure 100 described above, which will not be described in detail herein.

[0063] The method for preparing the package structure 100 comprises the following steps:

[0064] S1: at least two main function chips 2 are arranged at intervals on the front side of the main circuit board 1;

[0065] Specifically, step S1 is: at least two main function chips 2 are arranged at intervals on the front side of the main circuit board 1 in a flip-chip manner.

[0066] Furthermore, the main function chip 2 is provided with a first solder ball 21 for electrically connecting to the main circuit board 1 , and the first solder ball 21 is used to achieve a fixed connection and an electrical connection between the main function chip 2 and the main circuit board 1 .

[0067] It can be understood that the main function chips 2 on the packaging structure 100 can be all arranged on the front side of the main circuit board 1 , or can be partially arranged on the front side of the main circuit board 1 .

[0068] S2: Connect the antenna board 3 to one side of the two main function chips 2 spaced apart from the main circuit board 1;

[0069] Specifically, in an embodiment in which a metal solder ball 31 or a metal column for connecting to the main function chip 2 is provided on the antenna board 3, the connecting portion of the antenna board 3 on the main function chip 2 has a metal plating 22 to facilitate welding with the metal solder ball 31 or the metal column; of course, this is not limited to the above, and it is understandable that a connecting terminal corresponding to the metal solder ball 31 or the metal column can also be provided on the connecting portion of the antenna board 3, so as to realize a fixed connection between the antenna board 3 and the main function chip 2 through welding between the metal solder ball 31 and the connecting terminal.

[0070] Furthermore, in the embodiment where the antenna board 3 is connected to the main function chip 2 via a metal solder ball 31 or a metal column; the method for preparing the package structure 100 further includes the following step after step S2: filling an insulating material between the antenna board 3 and the main function chip 2. The insulating material is coated on the periphery of the metal solder ball 31 or the metal column, and can position the metal solder ball 31 or the metal column, and prevent the metal solder ball 31 or the metal column from being oxidized by contact with the outside air.

[0071] Specifically, in an embodiment in which an adhesive layer 33 for connecting to the main function chip 2 is provided on the antenna board 3, step S2 is specifically: directly connecting the antenna board 3 to the side of the two main function chips 2 spaced apart from the main circuit board 1 through the adhesive layer 33.

[0072] S3: Connect the heat dissipation cover 4 to the at least two main function chips 2 .

[0073] Specifically, when installing the heat dissipation cover 4, hot pressing welding, reflow soldering or adhesive material can be used to achieve the connection between the heat dissipation cover 4 and the connecting part of the heat dissipation cover 4. At the same time, the heat dissipation cover 4 and the connecting part of the heat dissipation cover 4 can be directly connected or indirectly connected through thermal conductive materials.

[0074] Furthermore, in an embodiment in which hot pressing welding or reflow soldering is used to realize the connection between the heat dissipation cover 4 and the main function chip 2, a metal plating layer 22 is provided at the connection portion of the heat dissipation cover 4. On the one hand, it facilitates the heat conduction of the main function chip 2 and enhances the heat dissipation effect of the heat dissipation cover 4; on the other hand, it facilitates the fixed connection between the heat dissipation cover 4 and the connection portion of the heat dissipation cover 4 by welding.

[0075] Furthermore, the method for preparing the packaging structure 100 further includes the following step located between step S1 and step S2 : filling insulating material between the main function chip 2 and the main circuit board 1 .

[0076] Specifically, the space between the main function chip 2 and the main circuit board 1 is filled with insulating material so that the insulating material covers the outer periphery of the first solder ball 21 to prevent the first solder ball 21 from contacting other circuits on the main circuit board 1 and causing a short circuit. At the same time, the insulating material covers the periphery of the first solder ball 21, which can position the first solder ball 21 and prevent the first solder ball 21 from being oxidized by contact with the outside air.

[0077] Furthermore, the heat dissipation cover 4 further includes a connection platform 43 connected to the main circuit board 1 , and step S3 specifically includes: connecting the heat dissipation cover 4 to the at least two main function chips 2 and the main circuit board 1 .

[0078] Specifically, there is an adhesive material, such as glue or tin, between one end of the connecting platform 43 facing the main circuit board 1 and the main circuit board 1 to achieve a fixed connection between the connecting platform 43 and the main circuit board 1 .

[0079] To sum up, the packaging structure 100 in the present invention can reduce the planar size of the packaging structure 100 by arranging at least two of the main function chips 2 at intervals on the front side of the main circuit board 1, so that at least two of the main function chips 2 do not occupy the space on the back side of the main circuit board 1, and facilitate the connection between the heat dissipation cover 4 and the main function chip 2, that is, it is easy to design a corresponding heat dissipation structure for dissipating heat from the main function chip 2, and the structure is simple.

[0080] It should be understood that although this specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each implementation mode may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

[0081] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A packaging structure, comprising a main circuit board, an antenna board, and at least two main function chips electrically connected to the main circuit board; characterized in that: At least two of the main function chips are spaced apart on the front side of the main circuit board, and the antenna board is connected to a side of the two spaced apart main function chips away from the main circuit board; the packaging structure also includes a heat dissipation cover connected to a side of the at least two main function chips away from the main circuit board, the heat dissipation cover having a receiving cavity for accommodating the antenna board; and a hollow portion is provided at a position on the heat dissipation cover corresponding to the antenna board; an antenna board connecting portion and a heat dissipation cover connecting portion are provided on a side of the main function chip away from the main circuit board, and the antenna board connecting portion and / or the heat dissipation cover connecting portion have a metal coating so as to be connected to the antenna board and the heat dissipation cover through the metal coating.

2. The packaging structure according to claim 1, wherein: The antenna board is provided with metal solder balls or metal pillars for connecting with the main function chip.

3. The packaging structure according to claim 2, wherein: An insulating material covering the metal solder balls or metal columns is provided between the antenna board and the main function chip.

4. The packaging structure according to claim 1, wherein: The antenna board is provided with an adhesive layer for connecting with the main function chip.

5. The packaging structure according to claim 4, characterized in that: The adhesive layer is a resin adhesive layer or a bubble film layer.

6. The packaging structure according to claim 1, wherein: The main function chip is provided with a first solder ball for electrically connecting to the main circuit board, and an insulating material covering the first solder ball is provided between the main function chip and the main circuit board.

7. The packaging structure according to claim 1, wherein: The heat dissipation cover also includes a connection platform connected to the main circuit board.

8. A method for preparing a packaging structure, characterized in that: The preparation method comprises the following steps: S1: at least two main function chips are arranged at intervals on the front of the main circuit board, an antenna board connection portion and a heat dissipation cover connection portion are arranged on a side of the main function chip away from the main circuit board, and the antenna board connection portion and / or the heat dissipation cover connection portion have a metal plating layer; S2: Connecting the antenna board to the metal plating layer of the antenna board connecting portion of the two main function chips arranged at intervals; S3: Opening a hollow portion at a position on the heat dissipation cover corresponding to the antenna board, and connecting the heat dissipation cover to the metal plating layer of the heat dissipation cover connecting portion of the at least two main function chips.

9. The method for preparing a packaging structure according to claim 8, wherein: The method for preparing the packaging structure further includes the following step located between step S1 and step S2: filling insulating material between the main function chip and the main circuit board.

10. The method for preparing a packaging structure according to claim 8, wherein: The antenna board is connected to the main function chip via metal solder balls or metal columns; the method for preparing the packaging structure also includes the following step located between steps S2 and S3: filling insulating material between the antenna board and the main function chip.

11. The method for preparing a packaging structure according to claim 8, wherein: The antenna board is connected to the main function chip through an adhesive layer.

12. The method for preparing a packaging structure according to claim 8, wherein: The heat dissipation cover also includes a connection platform connected to the main circuit board.

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