Power board

Abstract

The invention provides a power board. The power board comprises a plurality of power chips; a first prefabricated plate, wherein the plurality of power chips are embedded in the first prefabricated plate; the plurality of power chips are arranged on the first prefabricated plate, the plurality of conductive pattern layers and the plurality of insulating layers are alternately stacked above and / or below the first prefabricated plate, and the plurality of power chips are electrically connected with the plurality of conductive pattern layers. According to the power board, the bending degree of the power board can be adjusted by adjusting the position of the prefabricated board, and the power board has excellent heat dissipation performance.

Description

Technical Field

[0001] This application mainly relates to the field of chip packaging, and particularly to a power board. Background Art

[0002] A printed circuit board, abbreviated as PCB (Printed Circuit Board), also known as a printed board, is one of the important components of electronic products. A printed circuit board generally has a copper foil coated on an insulating board, so it can also be called a copper-clad laminate. PCBs can be divided into single-sided printed boards and double-sided printed boards. A single-sided printed board refers to a printed board with conductive patterns on one side, and a double-sided printed board refers to a printed board with conductive patterns on both sides. On an insulating substrate with copper foils on both sides, printed circuits are formed on the substrate through printing and etching methods, and the electrical interconnection between the two sides is achieved through metallized holes. Printed circuit boards can be used for packaging power chips. There are many problems in the process of packaging power chips on printed circuit boards. For example, how to make the curvature of the power board meet the requirements and how to ensure the heat dissipation performance of the power chips. Summary of the Invention

[0003] The technical problem to be solved by this application is to provide a power board that has the technical effects of adjustable curvature and excellent heat dissipation performance.

[0004] To solve the above technical problem, this application provides a power board, including: a plurality of power chips; a first prefabricated board, wherein the plurality of power chips are embedded in the first prefabricated board; a plurality of conductive pattern layers and a plurality of insulating layers, the plurality of conductive pattern layers and the plurality of insulating layers are alternately stacked above and / or below the first prefabricated board, and wherein the plurality of power chips are electrically connected to the plurality of conductive patterns.

[0005] In an embodiment of this application, the plurality of power chips are embedded in a substrate, and the substrate is embedded in the first prefabricated board.

[0006] In an embodiment of this application, a second prefabricated board is further included, the second prefabricated board is located above or below the first prefabricated board, and wherein at least one of the conductive pattern layers and / or the insulating layers is located between the first prefabricated board and the second prefabricated board.

[0007] In an embodiment of this application, the first prefabricated board is located at the bottom layer of the power board, the second prefabricated board is located at the top layer of the power board, and wherein the plurality of conductive pattern layers and the plurality of insulating layers are located between the first prefabricated board and the second prefabricated board.

[0008] In an embodiment of this application, the first prefabricated board is located at the bottom layer of the power board, and there is a preset distance between the second prefabricated board and the first prefabricated board.

[0009] In one embodiment of the present application, the second prefabricated board is located at the bottom layer of the power board, and the first prefabricated board is located above the second prefabricated board.

[0010] In one embodiment of the present application, a heat dissipation block is further included. The heat dissipation block is embedded in the second prefabricated board, and the top surface of the heat dissipation block is in contact with the bottom surface of the substrate. Among them, the plurality of power chips are embedded in the substrate, and the substrate is embedded in the first prefabricated board.

[0011] In one embodiment of the present application, part of the conductive pattern layer and part of the insulating layer are located above the first prefabricated board, and the remaining conductive pattern layer and the remaining insulating layer are located below the first prefabricated board.

[0012] In one embodiment of the present application, a plurality of heat dissipation columns are further included. The plurality of heat dissipation columns are located below the first prefabricated board. The top surfaces of the plurality of heat dissipation columns are in contact with the substrate, and the bottom surfaces of the plurality of heat dissipation columns are in contact with the conductive pattern layer located below them. Among them, the plurality of power chips are embedded in the substrate, and the substrate is embedded in the first prefabricated board.

[0013] In one embodiment of the present application, the prefabricated board includes at least two preset conductive pattern layers and at least one connection layer, and each connection layer is located between adjacent preset conductive pattern layers.

[0014] The power board of the present application can adjust the curvature of the power board by adjusting the position of the prefabricated board and has excellent heat dissipation performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings are provided to provide a further understanding of the present application, and they are incorporated and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and, together with this specification, serve to explain the principles of the present application. In the accompanying drawings:

[0016] Figure 1 is a cross-sectional schematic diagram of a power board in one embodiment of the present application;

[0017] Figure 2 is Figure 1 a cross-sectional schematic diagram of the power board along the line A-A in

[0018] Figure 3 is a cross-sectional schematic diagram of a power board in another embodiment of the present application;

[0019] Figure 4 is a cross-sectional schematic diagram of a power board in one embodiment of the present application;

[0020] Figure 5 is a cross-sectional schematic diagram of a power board in another embodiment of the present application;

[0021] Figure 6 It is a schematic cross-sectional view of a power board in an embodiment of the present application.

[0022] Reference numerals

[0023] Power chip 110 Heat sink 160

[0024] First prefabricated board 120 Third connection layer 170

[0025] First preset conductive pattern layer 121 Solder 180

[0026] First connection layer 122 Protective layer 190

[0027] Second preset conductive pattern layer 123 Substrate 210

[0028] Conductive pattern layer 130 Heat dissipation column 220

[0029] Insulating layer 140 Metal hole 230

[0030] Second prefabricated board 150 First pad 241

[0031] Third preset conductive pattern layer 151 Second pad 242

[0032] Second connection layer 152 Third pad 243

[0033] Fourth preset conductive pattern layer 153 Fourth pad 244 Detailed implementation manners

[0034] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some examples or embodiments of the present application. For those of ordinary skill in the art, without creative efforts, the present application can also be applied to other similar scenarios based on these drawings. Unless obvious from the language context or otherwise stated, the same reference numerals in the figures represent the same structure or operation.

[0035] As shown in the present application and the claims, unless the context clearly indicates an exception, words such as "a", "an", "one" and / or "the" are not specifically singular, but may also include the plural. Generally speaking, the terms "comprising" and "including" only indicate the inclusion of the clearly identified steps and elements, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0036] Unless otherwise specifically stated, the relative arrangements of components and steps, numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application. At the same time, it should be understood that, for the sake of convenience in description, the dimensions of the various parts shown in the drawings are not drawn in actual proportional relationships. Technologies, methods, and devices known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, such technologies, methods, and devices should be regarded as part of the authorization specification. In all the examples shown and discussed here, any specific values should be construed as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that like reference numerals and letters denote like items in the following drawings, and thus, once an item is defined in one drawing, it does not need to be further discussed in subsequent drawings.

[0037] In the description of the present application, it should be understood that the orientation or positional relationships indicated by orientation words such as "front, rear, upper, lower, left, right", "lateral, vertical, perpendicular, horizontal", and "top, bottom" are generally based on the orientation or positional relationships shown in the drawings. These are only for the convenience of describing the present application and simplifying the description. Without contrary explanation, these orientation words do not indicate and imply that the devices or elements referred to must have a specific orientation or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of the present application; the orientation words "inside, outside" refer to the inside and outside relative to the contour of each component itself.

[0038] For the convenience of description, spatial relative terms such as "above...", "over...", "on the upper surface of...", "above" can be used here to describe the spatial positional relationships of one device or feature to other devices or features as shown in the drawings. It should be understood that the spatial relative terms are intended to encompass different orientations in use or operation in addition to the orientation depicted in the drawings for the device. For example, if the device in the drawing is inverted, the device described as "above other devices or structures" or "over other devices or structures" will then be positioned "below other devices or structures" or "under other devices or structures". Thus, the exemplary term "above..." can include both the orientations of "above..." and "below...". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and corresponding interpretations should be made for the spatial relative descriptions used here.

[0039] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Without additional declaration, the above terms have no special meaning, so it should not be construed as a limitation on the protection scope of this application. In addition, although the terms used in this application are selected from well-known and commonly used terms, some terms mentioned in the specification of this application may be selected by the applicant according to his or her judgment, and their detailed meanings are described in the relevant parts of this description. In addition, it is required to understand this application not only through the actual terms used, but also through the meaning implied by each term.

[0040] Next, the power board of this application will be described through embodiments.

[0041] Figure 1 is a cross-sectional schematic diagram of the power board in an embodiment, Figure 2 is Figure 1 the cross-sectional schematic diagram of the power board along line A-A in. Refer to Figure 1 and Figure 2 As shown, the power board includes 12 power chips 110, a first prefabricated board 120, a multi-layer conductive pattern layer 130, and a multi-layer insulating layer 140. The 12 power chips 110 are electrically connected to the multi-layer conductive pattern 130.

[0042] Specifically, the power board includes two rows of power chips 110, and each row includes 6 power chips 110. The arrangement and quantity of the power chips 110 are not limited to Figure 1 and Figure 2 the embodiments in, and can be set according to actual situations. The power chip 110 can be a silicon carbide substrate power chip, a silicon substrate power chip, or a silicon carbide-silicon hybrid substrate power chip.

[0043] The power chip 110 is embedded in the substrate 210. The substrate 210 has a groove for accommodating the power chip 110, and the power chip 110 can be connected to the substrate 210 through the solder 180 located between the power chip 110 and the bottom surface of the groove. The power chip 110 can be electrically connected to the substrate 210. The substrate 210 is embedded in the first prefabricated board 120. The first prefabricated board 120 has a cavity for accommodating the substrate 210, and the substrate 210 can be connected to the side wall of the cavity through insulating glue. The material of the substrate 210 can include metal copper.

[0044] In one embodiment, the first prefabricated board 120 includes a first preset conductive pattern layer 121, a first connection layer 122, and a second preset conductive pattern layer 123 that are stacked in sequence. The first preset conductive pattern layer 121 and the second preset conductive pattern layer 123 are conductive, and the first preset conductive pattern layer 121 and the second preset conductive pattern layer 123 can be copper foils with specific patterns. The first connection layer 122 is insulating, and the first connection layer 122 connects the first preset conductive pattern layer 121 and the second preset conductive pattern layer 123. The first connection layer 122 can be fiberglass. The number of preset conductive pattern layers in the first prefabricated board 120 is not limited to 2 layers. For example, the number of preset conductive pattern layers can be 4 layers, and a layer of the first connection layer is provided between two adjacent preset conductive pattern layers. The thickness of the first prefabricated board 120 can be adjusted by changing the number of preset conductive pattern layers.

[0045] The multi-layer conductive pattern layer 130 and the multi-layer insulating layer 140 are alternately stacked above the first prefabricated board 120. The conductive pattern layer 130 is conductive, and the conductive pattern layer 130 can be copper foil with a specific pattern. The insulating layer 140 is insulating and can be used to connect two adjacent conductive pattern layers 130. In some embodiments, the insulating layer 140 can include solid glue. The multi-layer conductive pattern layer 130 and the multi-layer insulating layer 140 can be alternately stacked above the first prefabricated board 120 using a lamination process. The number of conductive pattern layers 130 and insulating layers 140 is not limited to Figure 1 and Figure 2 As shown, for example, the number of conductive pattern layers 130 can be 4 layers, 5 layers, or 6 layers.

[0046] In the lamination process, the number of lamination times is positively correlated with the number of conductive pattern layers 130. Since the first prefabricated board 120 has been prepared before the lamination process, using the first prefabricated board 120 can reduce the number of lamination times, thereby improving the production efficiency of the power board.

[0047] Combined with Figure 1 and Figure 2 As shown, the power chip 110 can be connected to the solder pads on the surface of the power board through the metal vias 230 located between the conductive pattern layers 130. The solder pads can include a first solder pad 241, a second solder pad 242, a third solder pad 243, and a fourth solder pad 244. Among them, the first solder pad 241 can be electrically connected to the drain of the left power chip 110, the second solder pad 242 can be electrically connected to the source of the left power chip 110 and the drain of the right power chip 110, the third solder pad 243 can be electrically connected to the source of the left power chip 110, and the fourth solder pad 244 can be electrically connected to the gate of the power chip 110.

[0048] In one embodiment, the power board further includes a protective layer 190. The protective layer 190 covers the top conductive pattern layer 130. The protective layer 190 includes solder mask. The protective layer 190 can be used to protect the power board from erosion.

[0049] In one embodiment, the power board further includes a second prefabricated board 150. The second prefabricated board 150 includes a third preset conductive pattern layer 151, a second connection layer 152, and a fourth preset conductive pattern layer 153 stacked in sequence. The third preset conductive pattern layer 151 and the fourth preset conductive pattern layer 153 are conductive, and the third preset conductive pattern layer 151 and the fourth preset conductive pattern layer 153 can be copper foils with specific patterns. The second connection layer 152 is insulating, and the second connection layer 152 can be fiberglass. The second connection layer 152 connects the third preset conductive pattern layer 151 and the fourth preset conductive pattern layer 153. Other descriptions of the second prefabricated board 150 can refer to the description of the first prefabricated board 120 above, and will not be elaborated here.

[0050] The second prefabricated board 150 can be located above the first prefabricated board 120, and the two are connected by a third connection layer 170, and the third connection layer 170 is insulating. Using the first prefabricated board 120 and the second prefabricated board 150 simultaneously can further reduce the number of laminations. In addition, the second prefabricated board 150 can adjust the curvature of the power board.

[0051] Reference Figure 1 and Figure 3 as shown. In Figure 1 , the first prefabricated board 120 is located at the bottom layer of the power board, the second prefabricated board 150 is located above the first prefabricated board 120, and there is a first preset distance d1 between the second prefabricated board 150 and the first prefabricated board 120. In Figure 3 , the first prefabricated board 120 is located at the bottom layer of the power board, the second prefabricated board 150 is located at the top layer of the power board, and the multi-layer conductive pattern layer 130 and the multi-layer insulating layer 140 are located between the first prefabricated board 120 and the second prefabricated board 150. Setting the first prefabricated board 120 at the bottom layer of the power board can facilitate directly connecting a heat dissipation device to the back of the substrate 210, so that a good heat dissipation effect can be obtained. The first prefabricated board 120 located at the bottom layer will cause the power board to bend, and the second prefabricated board 150 located above the first prefabricated board 120 can balance the bending caused by the first prefabricated board 120.

[0052] There is a second preset distance d2 between the second prefabricated board 150 and the first prefabricated board 120. The second preset distance d2 is greater than the first preset distance d1. By adjusting the size of the preset distance, the stress applied to the power board by the first prefabricated board 120 and the second prefabricated board 150 can be adjusted, thereby adjusting the curvature of the power board. For example, in Figure 3In the figure, the first prefabricated board 120 and the second prefabricated board 150 are symmetrical about the insulating layer 140 located on the second layer. In this way, the stresses exerted by the two on the power board can cancel each other out, thereby reducing the degree of bending of the power board.

[0053] Reference Figure 3 As shown, the process of stacking each layer in the stacked power board may include the steps of: stacking the second prefabricated board 150, a layer of insulating layer 140 located below the second prefabricated board 150, and a layer of conductive pattern layer 130 located below the second prefabricated board 150. For the convenience of description, the above-stacked structure is referred to as the first stacked structure; stacking the first prefabricated board 120, a layer of insulating layer 140 located above the first prefabricated board 120, and a layer of conductive pattern layer 130 located above the first prefabricated board 120. For the convenience of description, the above-stacked structure is referred to as the second stacked structure; stacking the first stacked structure, the second stacked structure, and the insulating layer 140 located between the first stacked structure and the second stacked structure. The metal hole 230 can electrically connect the first stacked structure and the second stacked structure. Compared with the technical solution of stacking each layer of the power board layer by layer, preparing the power board through the above steps can reduce the diameter of the metal hole 230 on the premise that the electrical conductivity of the metal hole 230 meets the requirements. The power board includes a plurality of metal holes 230. Reducing the diameter of the metal hole 230 helps to increase the density of the metal holes 230 per unit area, thereby improving the current-carrying performance of the power board.

[0054] Figure 4 is a cross-sectional schematic diagram of a power board in an embodiment. Compared with Figure 1 In Figure 4 , the first prefabricated board 120 is located in the middle layer of the power board. There are two layers of conductive pattern layers 130 and two layers of insulating layers 140 stacked above the first prefabricated board 120, and two layers of conductive pattern layers 130 and two layers of insulating layers 140 stacked below the first prefabricated board 120. In other words, the conductive pattern layer 130 and the insulating layer 140 located above the first prefabricated board 120 are vertically symmetrical about the first prefabricated board 120 with the conductive pattern layer 130 and the insulating layer 140 located below. Arranging the first prefabricated board 120 in the middle layer of the power board is beneficial to reducing the degree of bending of the power board on the one hand and helps with the heat dissipation of the power board on the other hand. In this way, a balance between heat dissipation and the degree of bending is achieved. In some embodiments, the conductive pattern layer 130 and the insulating layer 140 located above the first prefabricated board 120 can be removed, and the conductive pattern layer 130 and the insulating layer 140 located below the first prefabricated board 120 can be retained.

[0055] In some other embodiments, part of the conductive pattern layer 130 and part of the insulating layer 140 are located above the first prefabricated board 120, and the remaining conductive pattern layer 130 and the remaining insulating layer 140 are located below the first prefabricated board 120. For example, there are a total of 6 conductive pattern layers 130, among which 4 conductive pattern layers 130 are located above the first prefabricated board 120 and 2 conductive pattern layers 130 are located below the first prefabricated board 120.

[0056] Figure 5 is a schematic cross-sectional view of a power board in another embodiment. Refer to Figure 5 As shown, the second prefabricated board 150 is located at the bottom layer of the power board, and the first prefabricated board 120 is located above the second prefabricated board 150. The third connection layer 170 is located between the first prefabricated board 120 and the second prefabricated board 150, and the third connection layer 170 can be used to connect the first prefabricated board 120 and the second prefabricated board 150.

[0057] In one embodiment, the power board further includes a heat sink 160. The heat sink 160 is embedded in the second prefabricated board 150, and the top surface of the heat sink 160 is in contact with the bottom surface of the substrate 210. The heat sink 160 can be used to dissipate heat from the substrate 210, thereby improving the heat dissipation effect of the power board. The material of the heat sink 160 can include copper.

[0058] Figure 6 is a schematic cross-sectional view of a power board in one embodiment. Refer to Figure 6 As shown, the power board may include a plurality of heat dissipation columns 220. The heat dissipation columns 220 are located between the first prefabricated board 120 and the adjacent conductive pattern layer 130 located below the first prefabricated board 120. The top and bottom surfaces of the heat dissipation columns 220 are in contact with the substrate 210 and the conductive pattern layer 130 respectively. The heat dissipation columns 220 can be used to transfer the heat generated by the power chip to the conductive pattern layer 130. The material of the heat dissipation columns 220 can include copper.

[0059] The basic concepts have been described above. Obviously, for those skilled in the art, the above application disclosure is only an example and does not constitute a limitation to this application. Although not explicitly stated here, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are proposed in this application, so such modifications, improvements, and corrections still fall within the spirit and scope of the exemplary embodiments of this application.

[0060] Meanwhile, this application uses specific terms to describe the embodiments of this application. For example, "an embodiment", "one embodiment", and / or "some embodiments" mean a certain feature, structure, or characteristic related to at least one embodiment of this application. Therefore, it should be emphasized and noted that the "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more at different positions in this specification does not necessarily refer to the same embodiment. In addition, certain features, structures, or characteristics in one or more embodiments of this application can be appropriately combined.

[0061] Similarly, it should be noted that, in order to simplify the description of this application disclosure and thus help the understanding of one or more application embodiments, in the previous description of the embodiments of this application, sometimes multiple features are grouped into one embodiment, drawing, or description thereof. However, this disclosure method does not mean that the features required by the object of this application are more than those mentioned in the claims. In fact, the features of the embodiment are fewer than all the features of the single embodiment disclosed above.

[0062] In some embodiments, numbers are used to describe the components and the quantity of attributes. It should be understood that such numbers used in the description of embodiments are, in some examples, modified by the modifiers "about", "approximately", or "substantially". Unless otherwise stated, "about", "approximately", or "substantially" indicate that the said numbers allow a variation of ±20%. Accordingly, in some embodiments, the numerical parameters used in the specification and claims are approximate values, and such approximate values can change according to the characteristics required by individual embodiments. In some embodiments, the numerical parameters should consider the specified significant digits and adopt the method of retaining the general number of digits. Although the numerical ranges and parameters used to confirm the breadth of the scope in some embodiments of this application are approximate values, in specific embodiments, the setting of such numerical values is as precise as possible within the feasible range.

[0063] Although this application has been described with reference to the current specific embodiments, those of ordinary skill in the art should recognize that the above embodiments are only used to illustrate this application, and various equivalent changes or substitutions can be made without departing from the spirit of this application. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the spirit of this application, they will fall within the scope of the claims of this application.

Claims

1. A power board, characterized in that, Comprising: A plurality of power chips (110); A first prefabricated board (120), wherein the plurality of power chips (110) are embedded in the first prefabricated board (120); A multi-layer conductive pattern layer (130) and a multi-layer insulating layer (140), the multi-layer conductive pattern layer (130) and the multi-layer insulating layer (140) are alternately stacked above and / or below the first prefabricated board (120), wherein the plurality of power chips (110) are electrically connected to the multi-layer conductive pattern (130).

2. The power board according to claim 1, characterized in that, The plurality of power chips (110) are embedded in a substrate (210), and the substrate (210) is embedded in the first prefabricated board (120).

3. The power board according to claim 1, wherein Further comprising a second prefabricated board (150), the second prefabricated board (150) is located above or below the first prefabricated board (120), wherein at least one layer of the conductive pattern layer and / or the insulating layer is located between the first prefabricated board (120) and the second prefabricated board (150).

4. The power board according to claim 3, characterized in that, The first prefabricated board (120) is located at the bottom layer of the power board, and the second prefabricated board (150) is located at the top layer of the power board, wherein the multi-layer conductive pattern layer and the multi-layer insulating layer are located between the first prefabricated board (120) and the second prefabricated board (150).

5. The power board according to claim 3, characterized in that The first prefabricated board (120) is located at the bottom layer of the power board, and there is a preset distance between the second prefabricated board (150) and the first prefabricated board (120).

6. The power board according to claim 3, characterized in that, The second prefabricated board (150) is located at the bottom layer of the power board, and the first prefabricated board (120) is located above the second prefabricated board (150).

7. The power board according to claim 6, characterized in that Further comprising a heat sink (160), the heat sink (160) is embedded in the second prefabricated board (150), the top surface of the heat sink (160) is in contact with the bottom surface of the substrate (210), wherein the plurality of power chips (110) are embedded in the substrate (210), and the substrate (210) is embedded in the first prefabricated board (120).

8. The power board according to claim 1, characterized in that, Part of the conductive pattern layer and part of the insulating layer are located above the first prefabricated board (120), and the remaining conductive pattern layer and the remaining insulating layer are located below the first prefabricated board (120).

9. The power board according to claim 8, characterized in that Further comprising a plurality of heat dissipation columns (220), the plurality of heat dissipation columns (220) are located below the first prefabricated board (120), the top surfaces of the plurality of heat dissipation columns (220) are in contact with the substrate (210), and the bottom surfaces of the plurality of heat dissipation columns (220) are in contact with the conductive pattern layer located below them, wherein the plurality of power chips (110) are embedded in the substrate (210), and the substrate (210) is embedded in the first prefabricated board (120).

10. The power board according to any one of claims 1 to 9, characterized in that The prefabricated boards (120, 150) include at least two layers of preset conductive pattern layers (121, 151) and at least one layer of connection layers (122, 152), wherein each layer of connection layer is located between adjacent preset conductive pattern layers.

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