An encapsulation structure, a camera, and a method for manufacturing the encapsulation structure

Abstract

The present invention provides a packaging structure, a camera and a manufacturing method of the packaging structure. Among them, the packaging structure includes a printed circuit board, the printed circuit board includes a first surface and a second surface; a through hole penetrating the first surface and the second surface of the printed circuit board; a heat dissipation component fixed to the through hole; a conductive layer coated on the first surface of the printed circuit board; and a chip to be packaged disposed on the upper side of the conductive layer. The packaging structure has a better heat dissipation effect.

Description

Technical Field

[0001] The present invention relates to the technical field of component manufacturing, and in particular to a packaging structure, a camera and a method for manufacturing the packaging structure. Background Art

[0002] Chip on board (COB) packaging is commonly used in the testing and application of complementary metal oxide semiconductor (CMOS) image sensors (CIS). COB products have poor heat dissipation performance and their performance is greatly affected by temperature. Therefore, it is necessary to improve the heat dissipation design of the product during the product design process.

[0003] At present, the heat dissipation pathway of the chip is that the heat generated by the chip is conducted to the conductive layer (such as copper foil) connected to it, and then conducted to the printed circuit board (PCB). At this time, the printed circuit board becomes the main heat conduction carrier. Considering the limited heat dissipation capacity of the printed circuit board, the existing technology also improves the heat dissipation performance of the printed circuit board by adding vias. The traditional heat dissipation method is barely enough for chips with less heat generation, but it is not enough for the large-array CIS and COB packaging of chips with severe heat generation. If the heat dissipation is not properly solved, it will have a significant impact on the imaging quality of the CIS and even the entire system product. Therefore, there is an urgent need for a circuit board heat dissipation solution that can improve the heat dissipation efficiency to meet the heat dissipation requirements of large-array CIS and COB chips with severe heat generation. Summary of the invention

[0004] The object of the present invention is to provide a packaging structure, a camera and a method for manufacturing the packaging structure, wherein the packaging structure has a better heat dissipation effect.

[0005] In a first aspect, an embodiment of the present invention provides a packaging structure, which includes a printed circuit board, the printed circuit board including a first surface and a second surface; a through hole penetrating the first surface and the second surface of the printed circuit board; a heat dissipation component fixed to the through hole; a conductive layer coated on the first surface of the printed circuit board; and a chip to be packaged arranged on the upper side of the conductive layer.

[0006] The packaging structure of the present invention has the following beneficial effects: in this embodiment, since a heat dissipation component is fixed in the printed circuit board, the heat dissipation component has a good heat conduction ability, so the heat generated by the chip to be packaged can be quickly conducted away. For example, when the chip to be packaged is a CIS chip, the packaging structure has a good heat dissipation effect, so it will not affect the imaging quality of the CIS.

[0007] In a possible design, the encapsulation structure further includes: vias that penetrate the first surface and the second surface of the printed circuit board, as well as the conductive layer; wherein, the ground terminal of the conductive layer is connected to the ground terminal of the second surface of the printed circuit board through a wire. This structure can, on the basis of improving the heat dissipation performance of the printed circuit board by increasing the vias, further enhance the heat dissipation effect by using through holes.

[0008] In a possible design, the bottom of the heat dissipation component protrudes from the second surface of the printed circuit board, and the heat dissipation component is connected to the system housing or the heat sink through a wire. This structure can enable the heat generated by the chip to be encapsulated to be quickly conducted out.

[0009] In a possible design, the bottom of the heat dissipation component protrudes from the second surface of the printed circuit board, and the bottom of the heat dissipation component is connected to the ground terminal of the second surface of the printed circuit board by welding. A conductive layer is coated on the second surface of the printed circuit board, so that the bottom of the heat dissipation component is at the same horizontal height as the conductive layer coated on the second surface of the printed circuit board.

[0010] In a possible design, the shape of the through hole is cylindrical, the heat dissipation component is a copper pillar, and the number of through holes is one or more.

[0011] In a possible design, the area of the via is smaller than the area of the through hole.

[0012] In a second aspect, an embodiment of the present invention further provides a camera, which may include the above encapsulation structure.

[0013] In a third aspect, an embodiment of the present invention further provides a method for manufacturing an encapsulation structure, the method including:

[0014] Electroplating through holes on the printed circuit board, the through holes penetrating the first surface and the second surface of the printed circuit board; coating a conductive layer on the first surface of the printed circuit board; disposing the chip to be encapsulated on the conductive layer and performing wire bonding on the chip; fixing the heat dissipation component to the through holes.

[0015] In a possible design, the manufacturing method further includes:

[0016] Drilling N vias in the printed circuit board and the conductive layer, where N is a positive integer; wherein, the vias penetrate the first surface and the second surface of the printed circuit board, as well as the conductive layer and the chip to be encapsulated; wherein, the ground terminal of the conductive layer is connected to the ground terminal of the second surface of the printed circuit board through a wire.

[0017] In a possible design, the manufacturing method further includes:

[0018] Connecting the heat dissipation component to the system housing or the heat sink through a wire, wherein the bottom of the heat dissipation component protrudes from the second surface of the printed circuit board.

[0019] In a possible design, the manufacturing method further includes:

[0020] Connecting the bottom of the heat dissipation component to the ground terminal on the second surface of the printed circuit board by welding, where the bottom of the heat dissipation component protrudes from the second surface of the printed circuit board;

[0021] Coating a conductive layer on the second surface of the printed circuit board so that the bottom of the heat dissipation component and the conductive layer coated on the second surface of the printed circuit board are at the same horizontal height.

[0022] For the beneficial effects of the second and third aspects above, reference can be made to the first aspect. Description of the Drawings

[0023] Figure 1 A schematic cross-sectional view of the package structure provided by the embodiment of the present invention;

[0024] Figure 2 A schematic top view of the package structure provided by the embodiment of the present invention;

[0025] Figure 3 A schematic flowchart of the manufacturing method of the package structure provided by the embodiment of the present invention;

[0026] Figure 4 A schematic diagram of the manufacturing process provided by the embodiment of the present invention;

[0027] Figure 5 A bottom view of a package structure provided by the embodiment of the present invention. Detailed Embodiments

[0028] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meanings understood by those of ordinary skill in the art in the field to which the present invention belongs. The words such as "including" used herein mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects.

[0029] In view of the problems existing in the prior art, the embodiment of the present invention provides a package structure. Figure 1It is a cross-sectional view of the packaging structure 100. The packaging structure 100 includes a printed circuit board 101, a conductive layer 102, a chip to be packaged 103, a conductive layer 102', and a heat dissipation component 104. Among them:

[0030] The printed circuit board 101 includes a first surface 1011 and a second surface 1012; Figure 1 Three of the heat dissipation components 104 are fixed in three through holes of the printed circuit board 101. A conductive layer 102' is coated on the second surface 1012 of the printed circuit board 101, and a conductive layer 102 is coated on the first surface 1011 of the printed circuit board 101. The packaged chip 103 is disposed on the upper side of the conductive layer 102.

[0031] In this embodiment, in one possible case, the through holes in the printed circuit board 101 can penetrate the first surface and the second surface of the printed circuit board, but do not penetrate the conductive layer 102, as Figure 1 shown. This can achieve rapid heat conduction from the chip to be packaged by using the heat dissipation component. Since the heat dissipation component does not penetrate the conductive layer 102, the flatness of the conductive layer 102 can be ensured. The flatness of the conductive layer 102 can ensure the flatness of the bottom of the chip to be packaged on the upper side of the conductive layer 102, avoiding problems such as warping of the edge due to uneven heating or damage due to stress at the bottom of the chip to be packaged. In another possible case, the through holes in the printed circuit board 101 can penetrate the second surface and the first surface of the printed circuit board and also penetrate the conductive layer 102, so that rapid heat conduction from the chip to be packaged can be achieved by using the heat dissipation component. In another possible case, the through holes in the printed circuit board 101 can penetrate the second surface of the printed circuit board but do not penetrate the first surface, so that rapid heat conduction of the heat in the printed circuit board 101 can still be achieved by using the heat dissipation component.

[0032] In this embodiment, the bottom of the heat dissipation component 104 can protrude from the second surface 1012 of the printed circuit board 101. Without considering the flatness of the bottom of the packaging structure, the protruding bottom of the heat dissipation component 104 can be connected to the system housing or the heat sink through a wire. When considering the flatness of the bottom of the packaging structure, the bottom of the heat dissipation component 104 can be connected to the underlying conductive layer 102' (i.e., the ground terminal GND) of the second surface 1012 of the printed circuit board 101 by welding. When coating the conductive layer on the second surface of the printed circuit board, the bottom of the heat dissipation component can be made to be at the same horizontal height as the conductive layer coated on the second surface of the printed circuit board to ensure the flatness of the bottom.

[0033] In this embodiment, since the heat dissipation component is fixed in the printed circuit board and has a good heat conduction ability, the heat generated by the chip to be encapsulated can be quickly conducted away. For example, when the chip to be encapsulated is a CIS chip, the heat dissipation effect of the encapsulation structure is good, so it will not affect the CIS imaging quality.

[0034] It should be noted that in this embodiment, the through holes in the printed circuit board 101 can be three, or one or two, or more than three. The shape of the through holes in the printed circuit board 101 can be any shape. In this embodiment, the through holes are preferably cylindrical because cylindrical shapes are easier to manufacture during production and use for connection. The heat dissipation component can be a copper pillar or a copper alloy pillar. The copper alloy can be at least one of copper tin (CuSn), copper magnesium (CuMg), copper nickel (CuNi), copper zinc (CuZn), copper palladium (CuPd), copper gold (CuAu), copper rhenium (CuRe), copper tungsten (CuW), tungsten (W), tungsten alloy, nickel (Ni), ruthenium (Ru), and cobalt (Co). The number of heat dissipation components fixed in the through holes of the printed circuit board can be determined according to the size of the encapsulation structure, the amount of heat generated by the chip to be encapsulated, etc. The conductive layer 102 is also called a chip substrate or a bonding substrate, and the conductive layer 102 can be a layer of copper foil.

[0035] In a possible embodiment, on the basis of improving the heat dissipation performance of the printed circuit board by increasing the number of vias, the heat dissipation effect can be enhanced based on the Figure 1 shown encapsulation structure. As shown in the Figure 2 top view of the encapsulation structure shown, the encapsulation structure 100 in this embodiment may further include a via 105 that penetrates the first surface 1011 and the second surface 1012 of the printed circuit board 101 and the conductive layer 102; wherein, the ground terminal of the conductive layer 102 is connected to the conductive layer 102' (the conductive layer 102' can also be called the ground terminal GND) on the second surface 1012 of the printed circuit board 101 through a wire.

[0036] In this embodiment, this method will not affect the wire bonding and routing of the chip to be encapsulated, and the routing of the chip to be encapsulated is the same as the traditional method. On the basis of improving the heat dissipation performance of the printed circuit board by increasing the number of vias in the original encapsulation structure, the heat dissipation effect is further enhanced by adding heat dissipation components. A small part of the heat generated when the chip to be encapsulated works can still be transmitted by the via to the conductive layer 102' (such as copper foil) at the bottom layer of the printed circuit board. At the same time, most of the heat generated when the chip to be encapsulated works is transmitted through the heat dissipation component, and can be transmitted to the copper foil at the bottom layer of the printed circuit board, or can be connected to the shell of the system through a wire or other connecting carriers such as screws and solder, and then the shell is cooled.

[0037] Based on Figure 1For the encapsulation structure shown, this embodiment also provides a method for manufacturing Figure 1 the encapsulation structure shown, as Figure 3 shown, the manufacturing method includes the following steps.

[0038] S301, electroplate vias on the printed circuit board 101. Among them, the vias penetrate through the first surface 1011 and the second surface 1012 of the printed circuit board 101.

[0039] Exemplarily, as Figure 4 (a) in shows, electroplate a mechanical hole 104' from the bottom layer (i.e., the conductive layer 102') of the area where COB encapsulation is performed on the PCB to the upper surface of the PCB, and this mechanical hole 104' does not penetrate through the top layer (i.e., the conductive layer 102) of the upper surface of the PCB.

[0040] S302, coat the conductive layer 102 on the first surface 1011 of the printed circuit board 101.

[0041] S303, place the chip 103 to be encapsulated on the conductive layer 102 and perform chip wire bonding.

[0042] Continuing with the above example, exemplarily, as Figure 4 (b) in shows, place the CIS chip on the conductive layer 102 of the PCB, and then perform bonding wire bonding.

[0043] S304, fix the heat dissipation component 104 to the via.

[0044] Continuing with the above example, exemplarily, as Figure 4 (c) in shows, embed a copper column corresponding to the shape of the mechanical hole into the mechanical hole 104' in the PCB.

[0045] In a possible implementation manner, the manufacturing method further includes S305: drill N vias 105 in the printed circuit board 101 and the conductive layer 102.

[0046] Continuing with the above example, exemplarily, as Figure 4 (d) in shows, drill two vias in the top layer (conductive layer 102) of the area where COB encapsulation is performed on the PCB and connect them to the ground terminal of the bottom layer (i.e., the conductive layer 102').

[0047] The above method may further include: connecting the heat dissipation component 104 to the system housing or the heat sink by means of a wire or welding. In a possible implementation manner, when applying a conductive layer to the second surface of the printed circuit board, the bottom of the heat dissipation component may be at the same horizontal height as the conductive layer applied to the second surface of the printed circuit board, so as to make the bottom of the semiconductor structure flat, to ensure the stability of the device and facilitate the installation of the device. Exemplarily, according to Figure 4 The manufacturing method shown can obtain the bottom view of the package structure as shown in Figure 5 Figure.

[0048] An embodiment of the present invention further provides a camera including the above package structure. Since the heat dissipation effect of the package structure is good, the imaging quality of the camera is high.

[0049] Although the embodiments of the present invention have been described in detail above, it is obvious to those skilled in the art that various modifications and changes can be made to these embodiments. However, it should be understood that such modifications and changes are all within the scope and spirit of the present invention described in the claims. Moreover, the present invention described herein may have other embodiments and may be implemented or realized in various ways.

Claims

1. An encapsulation structure, characterized in that, Comprising: A printed circuit board, the printed circuit board including a first surface and a second surface; A through hole penetrating the first surface and the second surface of the printed circuit board, the surface of the through hole being electroplated with a conductive material; A heat dissipation component fixed to the through hole, the material of the heat dissipation component being metal; A conductive layer coated on the first surface of the printed circuit board; A chip to be encapsulated disposed on the upper side of the conductive layer; Further comprising: N vias penetrating the first surface and the second surface of the printed circuit board, as well as the conductive layer and the chip to be encapsulated, where N is a positive integer; Wherein, the grounding end of the conductive layer is connected to the grounding end of the second surface of the printed circuit board through a wire; the bottom of the heat dissipation component is connected to the grounding end of the second surface of the printed circuit board by welding; the area of the via is smaller than the area of the through hole.

2. The encapsulation structure according to claim 1, wherein The bottom of the heat dissipation component protrudes from the second surface of the printed circuit board, and the heat dissipation component is connected to the system housing or a heat sink through a wire.

3. The encapsulation structure according to claim 1, wherein The bottom of the heat dissipation component protrudes from the second surface of the printed circuit board, and a conductive layer is coated on the second surface of the printed circuit board such that the bottom of the heat dissipation component is at the same horizontal height as the conductive layer coated on the second surface of the printed circuit board.

4. The encapsulation structure according to claim 1, wherein The shape of the through hole is cylindrical, the heat dissipation component is a copper pillar, and the number of through holes is one or more.

5. A camera, characterized in that, The camera includes the packaging structure as claimed in claim 1.

6. A manufacturing method of a packaging structure, characterized in that The method includes: Providing a printed circuit board, the printed circuit board including a first surface and a second surface; Forming a through hole in the printed circuit board and electroplating the through hole with a conductive material, the through hole penetrating the first surface and the second surface of the printed circuit board; Fixing a heat dissipation component to the through hole, the material of the heat dissipation component being metal; Coating a conductive layer on the first surface of the printed circuit board; Disposing a chip to be encapsulated on the conductive layer and performing wire bonding on the chip; The method further includes: making N vias in the printed circuit board and the conductive layer, where N is a positive integer; wherein, the vias penetrate the first surface and the second surface of the printed circuit board, as well as the conductive layer and the chip to be encapsulated; Wherein, the grounding end of the conductive layer is connected to the grounding end of the second surface of the printed circuit board through a wire; the bottom of the heat dissipation component is connected to the grounding end of the second surface of the printed circuit board by welding; the area of the via is smaller than the area of the through hole.

7. The manufacturing method according to claim 6, wherein The method further includes: Connecting the heat dissipation component to the system housing or a heat sink through a wire, wherein the bottom of the heat dissipation component protrudes from the second surface of the printed circuit board.

8. The manufacturing method according to claim 6, characterized in that, The method further includes: The bottom of the heat dissipation component protrudes from the second surface of the printed circuit board; Coating a conductive layer on the second surface of the printed circuit board such that the bottom of the heat dissipation component is at the same horizontal height as the conductive layer coated on the second surface of the printed circuit board.

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