Power module, method for manufacturing the same, converter, and electronic device

Abstract

A power module (10) and a method for manufacturing the same are disclosed. The power module (10) includes a power assembly (11) and a drive board (12). The power assembly (11) includes a substrate (111), a power chip (112), and a package body (113). The power chip (112) is disposed on a mounting surface (1110) of the substrate (111). The package body (113) packages the power chip (112) on the substrate (111). The drive board (12) is disposed within the package body (113) on the side of the power chip (112) opposite the mounting surface (1110). The drive board (12) is electrically connected to the power chip (112). In this power module, parasitic parameters between the drive board (12) and the power assembly (11) can be reduced, thereby improving the electrical performance of the power module (10).

Description

Technical Field

[0001] This application relates to the field of chip packaging technology, and more particularly to power modules and their manufacturing methods, converters, and electronic devices.

Background Art

[0002] A power module is a module obtained by packaging a combination of multiple electronic power devices based on specific functions. In the prior art, a power module is connected to a drive board, and the switch of the power chip packaged in the power module is controlled by using the drive board. However, in the prior art, the parasitic parameters between the drive board and the power chip in the power module are excessive, which affects the electrical performance of the power module.

Summary of the Invention

[0003] Embodiments of this application protect a power module to reduce parasitic parameters between a drive board and the power module and improve the electrical performance of the power module.

[0004] Embodiments of this application further protect a method for manufacturing a power module, a converter including the power module, and an electronic device including the converter.

[0005] According to one aspect, this application protects a power module. The power module includes a power assembly and a drive board. The power assembly includes a substrate, a power chip, and a package body. The power chip is disposed on the mounting surface of the substrate. The package body packages the power chip on the substrate. The drive board is located on the side of the power chip opposite to the mounting surface and is disposed in the package body. The drive board is electrically connected to the power chip.

[0006] In the power module according to this embodiment, the drive board is disposed within the package body of the power assembly, and the drive board is positioned on the side of the power chip opposite to the mounting surface, so that the distance between the drive board and the power chip is shortened. Also, the connection line between the power chip and the drive board becomes shorter, whereby the parasitic parameters of the connection line between the power chip and the drive board are effectively reduced. That is, the parasitic parameters of the power module are reduced, and the electrical performance of the power module is improved. Further, the drive board is disposed within the package body of the power assembly, that is, the drive board is disposed inside the power assembly. This can effectively reduce the planar area of the power module as compared with disposing the drive board and the power assembly on the same plane. When the package body is formed for the power assembly, the thickness of the power assembly is usually greater than 5 mm in order to ensure the strength of the power assembly. This thickness is sufficient to enable embedding the drive board in the package body of the power assembly without increasing the thickness of the power assembly. That is, disposing the drive board within the package body does not affect the thickness of the power assembly, whereby the integration of the power module is effectively improved, the package size is reduced, and the cost of the power module is reduced.

[0007] It can be understood that there are mainly two parasitic parameters in the parasitic parameters, namely parasitic inductance and parasitic resistance. The magnitude of the parasitic inductance is mainly affected by two factors. One is the length of the connection line, and the longer the connection line, the greater the parasitic inductance. The other is the area surrounded by the connection line, and the larger the area surrounded by the connection line, the greater the parasitic inductance. In the case of parasitic resistance, the longer the connection line, the greater the parasitic resistance. Therefore, in this application, a shorter distance between the drive board and the power chip indicates a shorter connection line between the drive board and the power chip, and the area surrounded by the connection line also becomes smaller, thereby effectively reducing the parasitic inductance and parasitic resistance of the power module and improving the electrical performance of the power module.

[0008] In some embodiments, in the direction perpendicular to the mounting surface, the distance between the drive board and the power chip is smaller than the distance between the drive board and the surface of the package body on the side opposite to the mounting surface. In this embodiment, by requiring that the distance between the drive board and the power chip is smaller than the distance between the drive board and the surface of the package body on the side opposite to the mounting surface, it is ensured that the distance between the drive board and the power chip is sufficiently short, thereby ensuring that the parasitic parameters of the connection line between the drive board and the power chip are sufficiently small, and effectively improving the electrical performance of the power module.

[0009] In some embodiments, the power assembly further includes pins. The pins penetrate through the drive board and a part of the package body. One end of the pin is disposed on the mounting surface and electrically connected to the power chip, and the other end of the pin is exposed from the package body. The pins are configured to realize an electrical connection between the power chip and the circuit board. Certainly, in another embodiment, the pins of the power chip may be alternatively configured to realize an electrical connection between the power chip and the drive board. Alternatively, the pins may not penetrate through the drive board. Alternatively, a structure other than the pins may be used to connect the power chip to the circuit board.

[0010] In some embodiments, the drive board is electrically connected to the power chip via pins. Specifically, by electrically connecting the pins to the drive board, the drive board is electrically connected to the power chip. The pins can realize the electrical connection between the power chip and the drive chip on the drive board, and can also realize the electrical connection between the power chip and an external circuit board, thereby simplifying the structure of the power module.

[0011] In some embodiments, the power module further includes a conductor. The conductor is located between the power chip and the drive board. The power chip is connected to the drive board via the conductor. Since the drive board is arranged in the package body of the power assembly, the distance between the drive board and the power chip is shortened. Also, the connection line (conductor) connecting the drive board and the power chip becomes shorter, thereby effectively reducing the parasitic parameters of the connection line of the power module and improving the electrical performance of the power module.

[0012] In some embodiments, the conductor is a copper bar, and both ends of the copper bar are electrically connected to the power chip and the drive board respectively. The length of the copper bar is equal to the distance between the drive board and the power chip. It can be understood that the length direction of the copper bar is the flowing direction of the current in the copper bar. Therefore, the length of the copper bar is the shortest, thereby effectively reducing the parasitic parameters of the connection line of the power module and improving the electrical performance of the power module.

[0013] In some embodiments, the conductor is a lead frame. The lead frame includes a first terminal and a second terminal connected to each other. The first terminal is electrically connected to the power chip. The second terminal is electrically connected to the drive board. In this implementation, the lead frame has fairly good current-carrying capacity, thereby effectively reducing the parasitic parameters of the power module and effectively improving the heat dissipation capacity of the power chip. Also, two power chips can be electrically connected via the lead frame, thereby effectively reducing the manufacturing process of the power module and improving the production efficiency of the power module.

[0014] In some embodiments, the lead frame further includes a third terminal electrically connected to the first terminal, and the third terminal is electrically connected to the pin. Specifically, the lead frame can also realize the electrical connection between the pin and the power chip, so there is no need to introduce additional leads to connect the power chip and the pin. Therefore, the structure of the power module becomes simpler, the manufacturing process of the power module is reduced, and the production efficiency of the power module is improved. Also, compared with leads, the lead frame has stronger current-carrying capacity and smaller parasitic parameters, so the heat dissipation effect of the power chip can be further improved.

[0015] In some embodiments, the package body is formed using a plastic packaging process. The package body formed using the plastic packaging process has good sealing performance, so the moisture resistance and reliability of the packaged structure can be improved.

[0016] In some embodiments, the power module further includes a package housing. The power assembly and the drive board are housed within the package housing. The ends of the pins on the side opposite the power chip extend outside the package housing. The package body is injected into the gaps within the package housing using a housing packaging process. In this application, the package body is formed using a housing packaging process. This process is simple, thereby effectively improving the production efficiency of the power module.

[0017] In some embodiments, the drive board and the power assembly constitute a packaged structure. The surface of the substrate on the side opposite the power chip is the back surface. The back surface is exposed from the package body. The power module further includes a heat sink. The heat sink contacts the back surface and is fixed to the packaged structure. By directly contacting the back surface of the substrate with the heat sink, the heat of the power chip can be quickly transferred to the heat sink and then transmitted to the outside by the heat sink, thereby effectively improving the heat dissipation efficiency of the power chip.

[0018] In some embodiments, the drive board includes a central region and an edge region surrounding the central region. The central region is disposed opposite the power assembly. The packaged structure includes mounting holes. The mounting holes are located in the edge region and penetrate through the drive board and the package body in the direction from the drive board to the power chip. The heat sink is connected to the packaged structure through the mounting holes. The edge region and the package body located in the edge region can be understood as the mounting part of the packaged structure. Therefore, the packaged structure is fixed to another component using the mounting part.

[0019] In some embodiments, the surface of the edge region opposite to the power chip is exposed from the package body so that a screw is fixed through the surface of the edge region opposite to the power chip. The package body is made of a brittle material and is prone to breakage under high stress. Since the package body is not disposed in the edge region, the screw directly transmits the tightening force to the drive board, thereby reducing the stress applied to the package body and avoiding the risk of the package body cracking due to the screw directly transmitting the tightening force to the package body.

[0020] In some embodiments, there are two power assemblies. The mounting surfaces of the two power assemblies are arranged opposite to each other and are electrically connected to each other. The package bodies of the two power assemblies are connected. The drive board is disposed between the two power assemblies and is electrically connected to at least one of the power assemblies. In this embodiment, the drive board is embedded between the two power assemblies, shortening the distance between the drive board and the power chips of the two power assemblies, further shortening the connection lines between the drive board and the power chips of the two power assemblies, thereby effectively reducing the parasitic parameters of the connection lines and improving the electrical performance of the power module.

[0021] According to a second aspect, this application protects a converter. The converter includes a circuit board and a power module according to any of the above embodiments. The power module is electrically connected to the circuit board. The integration and electrical performance of the converter having the power module provided in this application are effectively improved.

[0022] According to a third aspect, this application protects an electronic device. The electronic device includes the above converter, and the converter is configured to convert the electrical signals of the electronic device. The integration and electrical performance of the electronic device having the converter provided in this application are effectively improved.

[0023] According to a fourth aspect, this application protects a method for manufacturing a power module. The manufacturing method includes: preparing a first power board, the first power board including a substrate and a power chip disposed on a mounting surface of the substrate; preparing a drive board, disposing the drive board on a side of the power chip opposite to the mounting surface, and electrically connecting the drive board to the power chip to form a structure to be packaged; forming a power module by packaging the structure to be packaged using a package body.

[0024] In the method for manufacturing a power module in this application, a drive board is arranged on the side of the power chip opposite to the mounting surface, and the drive board is electrically connected to the power chip to form a structure to be packaged, and then the structure to be packaged is packaged to form a packaged structure. Specifically, by packaging the drive board and the power chip together, the distance between the drive board and the power chip can be shortened. Also, the connection line between the power chip and the drive board becomes shorter, thereby effectively reducing the parasitic parameters of the connection line between the power chip and the drive board, that is, reducing the parasitic parameters of the power module and improving the electrical performance of the power module. Further, the drive board and the first power board are packaged together. Compared with arranging the drive board and the first power board on the same plane, this can effectively reduce the planar area of the power module. When packaging the first power board, in order to ensure the strength of the first power board after packaging, the thickness of the first power board after packaging is usually greater than 5 mm. This thickness is sufficient to enable the drive board and the first power board to be packaged together without increasing the thickness of the first power board. That is, packaging the drive board and the first power board together does not affect the thickness obtained after packaging, thereby effectively improving the integration of the power module, reducing the package size, and reducing the cost of the power module.

[0025] In some embodiments, the manufacturing method further includes forming a conductor electrically connected to the power chip on the surface of the power chip on the side opposite to the mounting surface before placing the drive board on the side of the power chip opposite to the mounting surface, and when the drive board is placed on the side of the power chip opposite to the mounting surface, the drive board is electrically connected to the conductor. The conductor is configured to connect the power chip to the drive board in a subsequent process to reduce the parasitic parameters of the power module and improve the electrical performance of the power module.

[0026] In some embodiments, the conductor is a copper bar, or the conductor is a lead frame. The length of the copper bar is equal to the distance between the drive board and the power chip. It can be understood that the length direction of the copper bar is the direction of the current flow in the copper bar. Therefore, the length of the copper bar is the shortest, that is, the connection line between the drive board and the power chip is the shortest, thereby effectively reducing the parasitic parameters of the connection line of the power module and improving the electrical performance of the power module. When the conductor is a lead frame, the lead frame realizes both the electrical connection between the pins and the power chip and the electrical connection between the two power chips. Therefore, there is no need to introduce additional leads to connect the power chip and the pins and to connect the two power chips to each other. Accordingly, the structure of the power module becomes simpler, the manufacturing process of the power module is reduced, and the production efficiency of the power module is improved. Also, compared with leads, the lead frame has a stronger current-carrying capacity and smaller parasitic parameters. Therefore, the heat dissipation effect of the power chip can be further improved.

[0027] In some embodiments, the manufacturing method further includes fixing the pins to the mounting surface when the power chip is disposed on the mounting surface of the substrate, and when the drive board is disposed on the side of the power chip opposite to the mounting surface, the pins penetrate the drive board. This helps to reduce the manufacturing process of the power module, reduce the production cost, and improve the production efficiency of the power module.

[0028] In some embodiments, the manufacturing method further includes, after the drive board is electrically connected to the first power board, preparing a second power board, disposing the second power board on the side of the drive board opposite to the first power board, and electrically connecting the second power board to the first power board, thereby forming a structure to be packaged. In this embodiment, the drive board is embedded between the two power boards, so that the distance between the drive board and the power chips of the two power boards is shortened, the connection lines between the drive board and the power chips of the two power boards are further shortened, thereby effectively reducing the parasitic parameters of the connection lines and improving the electrical performance of the power module.

[0029] In some embodiments, the structure to be packaged is packaged using a plastic packaging process. In this embodiment, the power module formed using the plastic packaging process has good sealing performance, and therefore, the moisture resistance and reliability of the power module can be improved.

[0030] In some embodiments, a specific method for packaging the structure to be packaged is as follows: prepare a package housing, fix the structure to be packaged in the package housing, and inject an adhesive into the package housing to fill the gaps therein. In this embodiment, the package body is formed using a housing packaging process. This process is simple, thereby effectively improving the production efficiency of the power module.

[0031] In some embodiments, a package body and a structure to be packaged constitute a packaged structure, the surface of the substrate on the side opposite to the power chip is the back surface, and the manufacturing method further includes preparing a heat sink, fixing the heat sink to the packaged structure, and contacting the heat sink with the back surface to improve the heat dissipation efficiency of the power chip.

[0032] In some embodiments, the drive board includes a central region and an edge region surrounding the central region. The central region is disposed opposite to the power assembly, and the edge region includes vias. The manufacturing method further includes forming vias and mounting holes penetrating the package body when packaging the structure to be packaged. A specific step of fixing the heat sink to the packaged structure is as follows: A screw passes through the mounting hole and is tightened to the heat sink. Certainly, in another embodiment, the heat sink may alternatively be fixed to the packaged structure using screws or another fixing method. Or, the packaged structure may alternatively be fixed to the heat sink by another connection method such as bonding or clamping.

[0033] In the power module of this embodiment, the drive board is disposed within the package body of the power assembly, and the drive board is located on the side of the power chip opposite to the mounting surface, so that the distance between the drive board and the power chip is shortened. Also, the connection line between the power chip and the drive board becomes shorter, thereby effectively reducing the parasitic parameters of the connection line between the power chip and the drive board, that is, reducing the parasitic parameters of the power module and improving the electrical performance of the power module.

Brief Description of the Drawings

[0034]

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Embodiments for Carrying Out the Invention

[0035] Hereinafter, embodiments of this application will be described with reference to the accompanying drawings within the embodiments of this application.

[0036] Figure 1 is a schematic diagram of the structure of an electronic device 100 according to an embodiment of this application.

[0037] The electronic device 100 includes a converter 1 and a housing 2. The converter 1 is housed in the housing 2, and the converter 1 is configured to convert the electrical signals of the electronic device 100. The electronic device 100 in this embodiment includes, but is not limited to, for example, electronic devices 100 equipped with a converter 1 such as a wind turbine, a solar power generator, an electric vehicle, and large household appliances. The integration and electrical performance of the electronic device 100 equipped with the converter 1 provided in this application are effectively improved.

[0038] Figure 2 is a schematic diagram of a partial structure of the converter 1 of the electronic device 100 shown in Figure 1.

[0039] Converter 1 includes a power module 10 and a circuit board 20. The power module 10 is attached to the circuit board 20, and the circuit board 20 is electrically connected to the power module 10 to control the power module 10. The converter 1 in this embodiment includes, but is not limited to, for example, a converter equipped with a power module 10 such as a DC-AC converter and a DC-DC converter. The integration and electrical performance of the converter 1 equipped with the power module 10 provided in this application are effectively improved.

[0040] FIG. 3 is a schematic diagram of the structure of the first embodiment of the power module 10 of the converter 1 shown in FIG. 2.

[0041] The power module 10 includes a power assembly 11 and a drive board 12. The power assembly 11 includes a substrate 111, a power chip 112, and a package body 113. The power chip 112 is disposed on the mounting surface 1110 of the substrate 111. The package body 113 packages the power chip 112 on the substrate 111. The drive board 12 is located on the side of the power chip 112 opposite to the mounting surface 1110 and is disposed in the package body 113, forming a structure 13 packaged together with the power assembly 11. The drive board 12 is electrically connected to the power chip 112 and drives the power chip 112 to operate. It can be understood that the package body 113 packages the drive board 12 and the power chip 112 on the substrate 111 to form the packaged structure 13.

[0042] In the power module 10 of this embodiment, the drive board 12 is disposed within the package body 113 of the power assembly 11, and the drive board 12 is positioned on the side of the power chip 112 opposite to the mounting surface 1110, so that the distance between the drive board 12 and the power chip 112 is shortened. Also, the connection line between the power chip 112 and the drive board 12 becomes shorter, whereby the parasitic parameters of the connection line between the power chip 112 and the drive board 12 are effectively reduced, that is, the parasitic parameters of the power module 10 are reduced, and the electrical performance of the power module 10 is improved. Further, the drive board 12 is disposed within the package body 113 of the power assembly 11, that is, the drive board 12 is disposed inside the power assembly 11. Compared with disposing the drive board 12 and the power assembly 11 on the same plane, this can effectively reduce the planar area of the power module 10. When the package body 113 is formed for the power assembly 11, the thickness of the power assembly 11 is usually greater than 5 mm in order to ensure the strength of the power assembly 11. This thickness is sufficient to enable embedding the drive board 12 in the package body 113 of the power assembly 11 without increasing the thickness of the power assembly 11. That is, disposing the drive board 12 within the package body 113 does not affect the thickness of the power assembly 11, whereby the integration of the power module 10 is effectively improved, the package size is is reduced, and the cost of the power module 10 is reduced.

[0043] It can be understood that the parasitic parameters mainly include two types: parasitic inductance and parasitic resistance. The magnitude of the parasitic inductance is mainly affected by two factors. One is the length of the connection line, and the longer the connection line, the greater the parasitic inductance. The other is the area surrounded by the connection line, and the larger the area surrounded by the connection line, the greater the parasitic inductance. In the case of parasitic resistance, the longer the connection line, the greater the parasitic resistance. Therefore, in this application, the shorter distance between the drive board 12 and the power chip 112 indicates a shorter connection line between the drive board 12 and the power chip 112, and the area surrounded by the connection line also becomes smaller, thereby effectively reducing the parasitic inductance and parasitic resistance of the power module 10 and improving the electrical performance of the power module 10.

[0044] The substrate 111 includes a support plate a1, a line layer a2, and a metal layer a3. The line layer a2 and the metal layer a3 are respectively formed on the two opposite surfaces of the support plate a1. By positioning the line layer a2 and the metal layer a3 on the two surfaces of the support plate a1 respectively, the flatness of the support plate a1 is ensured and the warping of the support plate a1 is prevented. The surface of the line layer a2 on the side opposite to the support plate a1 is the mounting surface 1110, that is, the power chip 112 is arranged on the surface of the line layer a2 on the side opposite to the support plate a1. The surface of the substrate 111 on the side opposite to the power chip 112 is the back surface 1111, that is, the surface of the metal layer a3 on the side opposite to the support plate a1 is the back surface 1111, and the back surface 1111 is exposed from the package body 113. The line layer a2 can be configured to realize the electrical connection between the power chip 112 and another device, or can be configured to realize the electrical connection between the power chips 112. Since the back surface 1111 of the metal layer a3 is exposed from the package body 113, the metal layer a3 can effectively transfer the heat of the power chip 112 to the outside, thereby improving the heat dissipation efficiency of the power chip 112. In addition, the metal layer a3 can further effectively increase the strength of the substrate 111.

[0045] In this embodiment, the support plate a1 can be made of an insulating and heat-dissipating material such as ceramic. The ceramic can be, for example, a ceramic material such as aluminum oxide, silicon nitride, or aluminum nitride. The ceramic material has a good heat dissipation effect and can quickly dissipate the heat related to the power chip 112. The line layer a2 and the metal layer a3 are made of a metal material such as, for example, copper, nickel, or aluminum material, and can quickly dissipate the heat related to the power chip 112. The line layer a2 and the metal layer a3 may be made of the same material or different materials. Also, the line layer a2 is further configured to realize an electrical connection between the power chip 112 and another line. Certainly, in another embodiment, the support plate a1 may alternatively be made of other insulating materials.

[0046] In this embodiment, the line layer a2 includes a first line a21 and a second line a22. The second line a22 is located on both sides of the first line a21. The surfaces of the first line a21 and the second line a22 on the side opposite to the support plate a1 together form the mounting surface 1110. The power chip 112 is disposed on the first line a21, and the power chip 112 is connected to the second line a22 via a lead. Certainly, the power chip 112 may alternatively be connected to the second line a22 using another conductive structure, and the second line a22 is connected to another element. That is, the second line a22 is configured to realize a connection between the power chip 112 and another element. Certainly, in another embodiment, the structure of the line layer a2 is not limited to the above description, and the specific structure of the line layer a2 can be configured according to the connection requirements of the power chip 112.

[0047] In this embodiment, one or more power chips 112 may exist. For example, in FIG. 3, there are two power chips 112. The two power chips 112 are spaced apart and arranged on the first line a21, and the two power chips 112 are electrically connected to each other via leads. The lead connection process is mature and simple and has a low cost. The power chip 112 may be an insulated gate bipolar transistor (IGBT), a metal-oxide semiconductor field-effect transistor (MOSFET), and / or a diode. The power chip 112 may be fixed to the first line a21 by welding, bonding, or the like. For example, when it is necessary to electrically connect the power chip 112 to the first line a21, the power chip 112 may be fixed to the first line a21 by welding. When it is not necessary to electrically connect the power chip 112 to the first line a21, the power chip 112 may be fixed to the first line a21 by other methods such as bonding. Certainly, in another embodiment, the two power chips 112 may alternatively be connected using a connection structure such as a lead frame.

[0048] The package body 113 in this embodiment is formed using a plastic packaging process. The package body 113 can be made of a plastic material such as, for example, an epoxy resin or silicone. The package body 113 formed using the plastic packaging process has good sealing performance, and thus, the moisture resistance and reliability of the packaged structure 13 can be improved. Specifically, the package body 113 is packaged in the region from the back surface 1111 of the substrate 111 to the side of the drive board 12 opposite to the power chip 112, and the package body 113 is not disposed at the edge on the side of the drive board 12 opposite to the power chip 112, thereby facilitating the fitting between the power chip 112 and the related structure. In another embodiment, the package body 113 may be formed using another process such as, for example, a housing packaging process instead.

[0049] The power assembly 11 further includes pins 114. The pins 114 penetrate through the drive board 12 and a part of the package body 113. One end of the pin 114 is disposed on the mounting surface 1110 and electrically connected to the power chip 112, and the other end of the pin 114 is exposed from the package body 113. Specifically, by disposing the pin 114 on the second line a22 corresponding to the pin 114, the pin 114 is electrically connected to the power chip 112 corresponding to the pin 114 via the second line a22. The pin 114 is configured to realize the electrical connection between the power chip 112 and the circuit board 20 (FIG. 2). Certainly, in another embodiment, the pins 114 of the power chip 112 may be configured to realize the electrical connection between the power chip 112 and the drive board 12 instead. Alternatively, the pins 114 may not penetrate through the drive board 12. Alternatively, the power chip 112 may be connected to the circuit board 20 using a structure other than the pins 114.

[0050] In a direction perpendicular to the mounting surface 1110, the distance between the drive board 12 and the power chip 112 is smaller than the distance between the drive board 12 and the surface of the package body 113 on the side opposite to the mounting surface 1110. In this embodiment, the distance between the drive board 12 and the power chip 112 needs to be smaller than the distance between the drive board 12 and the surface of the package body 113 on the side opposite to the mounting surface 1110, so that the distance between the drive board 12 and the power chip 112 is ensured to be sufficiently short, whereby the parasitic parameters of the connection line between the drive board 12 and the power chip 112 are ensured to be sufficiently small, and the electrical performance of the power module 10 is effectively improved.

[0051] In this embodiment, there are two pins 114, and the two pins 114 are respectively arranged on the second line a22 on both sides of the two power chips 112. In other words, the two power chips 112 are arranged between the two pins 114. The pin 114 can be welded to the second line a corresponding to the pin 114 using solder paste, or can be fixed to the second line a22 corresponding to the pin 114 by ultrasonic welding, silver sintering, or the like. The shape of the pin 114 can be a cylindrical shape, an elliptical cylinder shape, a rectangular parallelepiped shape, a polygonal shape, or the like. The shapes of the two pins 114 may be the same or different. The material of the pin 114 can be a metal or alloy having good electrical conductivity, such as Cu, Ag, or Al. Certainly, in another embodiment, the arrangement method of the power chip 112 and the pin 114 and the number of the pins 114 can be arranged according to actual requirements instead.

[0052] The drive board 12 includes a central region 121 and an edge region 122 surrounding the central region 121. The central region 121 is disposed opposite to the power assembly 11. Electronic elements such as, for example, a drive chip 123, a resistor 124, a capacitor, and an optical coupler are disposed in the central region 121 to form a drive circuit. The power chip 112 of the power assembly 11 is electrically connected to the drive chip 123. The packaged structure 13 includes a mounting hole 131. The mounting hole 131 is located in the edge region 122 and penetrates the drive board 12 and the package body 113 in the direction from the drive board 12 to the power chip 112. Related components are connected to the packaged structure 13 through the mounting hole. The edge region 122 and the package body 113 located in the edge region 122 can be understood as the mounting portion of the packaged structure 13. Therefore, the packaged structure 13 is fixed to another component using the mounting portion.

[0053] Surely, in one implementation scenario of another embodiment, the related components may instead be fixed to the packaged structure 13 using screws or other fixing methods. In another implementation scenario of another embodiment, the packaged structure 13 may instead be fixed to the related components by another connection method such as, for example, bonding or clamping. In yet another implementation scenario of another embodiment, small electronic elements such as, for example, the resistor 124, the capacitor, and the optical coupler may instead be partially disposed in the edge region 122. In still another implementation scenario of another embodiment, when it is not necessary to fix the drive board 12 to the related components, the drive board 12 may instead include only the central region 121, that is, the drive board 12 may not include the edge region 122.

[0054] In this embodiment, the surface of the edge region 122 on the side opposite to the power chip 112 is exposed from the package body 113 so that the screw 132 is fixed through the surface of the edge region 122 on the side opposite to the power chip 112. That is, the package body 113 is not disposed on the surface of the edge region 122 on the side opposite to the power chip 112. Further, the package body 113 is made of a brittle material and is likely to be damaged under a large stress. Since the package body 113 is not disposed in the edge region 122, the screw 132 directly transmits the tightening force to the drive board 12, thereby reducing the stress applied to the package body 113 and avoiding the risk of the package body 113 cracking by the screw 132 directly transmitting the tightening force to the package body 113.

[0055] The drive board 12 further includes a through hole 125. The through hole 125 is configured to allow the corresponding pin 114 to pass through so that the pin 114 passes through the drive board 12 and is connected to a related external element. In this embodiment, the pin 114 passes through the through hole 125 and is not electrically connected to the through hole 125. Certainly, in another embodiment, the pin 114 may be electrically connected to the drive board 12 through the through hole 125 so as to realize an electrical connection between the drive board 12 and the power chip 112.

[0056] The power module 10 further includes a heat sink 14. The heat sink 14 is in contact with the back surface 1111 and is fixed to the packaged structure 13. Specifically, the screw 132 is connected to the heat sink 14 through the mounting hole 131 to fix the heat sink 14 to the packaged structure 13. By the back surface 1111 of the substrate 111 being in direct contact with the heat sink 14, the heat of the power chip 112 can be quickly transmitted to the heat sink 14 and then transmitted to the outside by the heat sink 14, thereby effectively improving the heat dissipation efficiency of the power chip 112.

[0057] The power module 10 further includes a conductor 15. The conductor 15 is located between the power chip 112 and the drive board 12. The power chip 112 is connected to the drive board 12 via the conductor 15. Specifically, the drive chip 123 on the drive board 12 is connected to the power chip 112 of the power assembly 11 via the conductor 15. Since the drive board 12 is arranged within the package body 113 of the power assembly 11, the distance between the drive board 12 and the power chip 112 is shortened. Also, the connection line (conductor 15) connecting the drive board 12 and the power chip 112 becomes shorter, thereby effectively reducing the parasitic parameters of the connection line of the power module 10 and improving the electrical performance of the power module 10.

[0058] The conductor 15 in this embodiment can be implemented in a plurality of ways. Details will be described below.

[0059] In one implementation, as shown in FIG. 3, the conductor is a copper bar 15, and both ends of the copper bar 15 are electrically connected to the power chip 112 and the drive board 12, respectively. Specifically, both ends of the copper bar 15 are electrically connected to the power chip 112 and the drive chip 123 on the drive board 12, respectively. The number of copper bars 15 matches the number of power chips 112, and one copper bar 15 corresponds to one power chip 112. The length of the copper bar 15 is equal to the distance between the drive board 12 and the power chip 112. It can be understood that the length direction of the copper bar 15 is the direction of the current flow in the copper bar 15. Therefore, the length of the copper bar 15 is the shortest, thereby effectively reducing the parasitic parameters of the connection line of the power module 10 and improving the electrical performance of the power module 10. Certainly, in another embodiment, the power chip 112 may be connected to the drive board 12 using another conductive structure such as a lead, for example.

[0060] FIG. 4 is a schematic diagram of the structure of another implementation of the power module 10 shown in FIG. 3.

[0061] In another implementation, the conductor is a lead frame (LF) 15. The lead frame 15 includes a first terminal 151 and a second terminal 152 connected to each other. The first terminal 151 is electrically connected to the power chip 112. The second terminal 152 is electrically connected to the drive board 12. Specifically, the second terminal 152 is electrically connected to the drive chip 123 on the drive board 12. The number of lead frames 15 matches the number of power chips 112. In this implementation, the lead frame 15 has a fairly good current-carrying capacity, thereby effectively reducing the parasitic parameters of the power module 10 and effectively improving the heat dissipation capacity of the power chip 112. Also, two power chips 112 can be electrically connected via the lead frame, thereby effectively reducing the manufacturing process of the power module 10 and improving the production efficiency of the power module 10.

[0062] The lead frame 15 further includes a third terminal 153 electrically connected to the first terminal 151, and the third terminal 153 is electrically connected to the pin 114. Specifically, the third terminal 153 is electrically connected to the second line a22 so as to be electrically connected to the pin 114. That is, the lead frame 15 in this implementation can also realize the electrical connection between the pin 114 and the power chip 112. Therefore, it is not necessary to introduce an additional lead to connect the power chip 112 and the pin 114. Accordingly, the structure of the power module 10 becomes simpler, the manufacturing process of the power module 10 is reduced, and the production efficiency of the power module 10 is improved. Also, compared with a lead, the lead frame 15 has a stronger current-carrying capacity and smaller parasitic parameters. Therefore, the heat dissipation effect of the power chip 112 can be further improved.

[0063] FIG. 5 is a schematic diagram of the structure of the second embodiment of the power module 10 shown in FIG. 2.

[0064] The structure of the power module 10 in this embodiment is substantially the same as that in the first embodiment. The difference is that in this embodiment, the power chip 112 is electrically connected to the drive board 12 via the pin 114, and by electrically connecting the pin 114 to the drive board 12, the drive board 12 is electrically connected to the power chip 112. Specifically, when the pin 114 passes through the drive board 12 through the through hole 125, it is electrically connected to the hole wall of the through hole 125, and the hole wall of the through hole 125 is electrically connected to the drive chip 123 on the drive board 12. The end of the pin 114 on the side far from the mounting surface 1110 is further connected to the circuit board 20 (FIG. 2). That is, the pin 114 can realize the electrical connection between the power chip 112 and the drive chip 123 on the drive board 12, and can also realize the electrical connection between the power chip 112 and the external circuit board 20, thereby simplifying the structure of the power module 10. It is certain that in another embodiment, the pin 114 may instead be configured to realize only the electrical connection between the power chip 112 and the drive chip 123 on the drive board 12.

[0065] FIG. 6 is a schematic diagram of the structure of the third embodiment of the power module 10 shown in FIG. 2.

[0066] The structure of the power module 10 in this embodiment is substantially the same as that in the first embodiment. The difference is that in this embodiment, the power module 10 further includes a package housing 16. The power assembly 11 and the drive board 12 are housed within the package housing 16. The ends of the pins 114 on the side opposite to the power chip 112 extend outside the package housing 16. The package body 113 is injected into the gaps within the package housing 16 using a housing packaging process. Specifically, a packaging material such as silicone gel or epoxy resin is injected into the package housing 16 to form the package body 113. In this application, the package body 113 is formed using a housing packaging process. This process is simple, thereby effectively improving the production efficiency of the power module 10.

[0067] The package housing 16 includes a base plate 161 and a cover 162. The cover 162 covers the base plate 161 and, together with the base plate 161, forms a space for housing the power assembly 11 and the drive board 12. Specifically, the metal layer a3 of the substrate 111 is fixed to the base plate 161 by welding, and the ends of the pins 114 on the side opposite to the power chip 112 extend outside the cover 162. In this embodiment, the metal layer a3 of the substrate 111 is fixed to the base plate 161 by welding. This helps to quickly transfer the heat transmitted from the power chip 112 to the substrate 111 to the base plate 161 while ensuring the connection strength between the substrate 111 and the base plate 161. Therefore, heat is transferred outside through the base plate 161, thereby effectively improving the heat dissipation efficiency of the power module 10. Certainly, the metal layer a3 of the substrate 111 may alternatively be fixed to the base plate 161 by other connection methods such as bonding or clamping.

[0068] In this embodiment, two power chips 112 are connected to each other using leads, and the power chip 112 is connected to the pin 114. Further, the power chip 112 is connected to the drive board 12 via the copper bar 15. To be sure, the power chip 112 may alternatively be connected to the drive board 12 via a lead. Also, the lead frame 15 may be used to connect two power chips 112 to each other, connect the power chip 112 to the pin 114, and connect the power chip 112 to the drive board 12.

[0069] The drive board 12 in this embodiment includes only the central region 121. Electronic elements such as a drive chip 123, a resistor 124, a capacitor, and an optical coupler are arranged in the central region 121 to form a drive circuit. The power chip 112 of the power assembly 11 is electrically connected to the drive chip 123.

[0070] The heat sink 14 is fixed to the base plate 161 and is in contact with the surface of the base plate 161 on the side opposite to the substrate 111. Therefore, the base plate 161 quickly transfers the heat of the power chip 112 to the outside through the heat sink 14, thereby improving the heat dissipation efficiency of the power chip 112 and further improving the electrical performance of the power module 10. Specifically, the heat sink 14 can be fixed to the base plate 161 by one of connection methods such as screwing, clamping, and bonding. To be sure, in another embodiment, the power module in this embodiment may alternatively not be provided with a heat sink.

[0071] FIG. 7 is a schematic diagram of the structure of the fourth embodiment of the power module 10 shown in FIG. 2.

[0072] The structure of the power module 10 in this embodiment is substantially the same as that in the first embodiment. The difference lies in that in this embodiment, there are two power assemblies 11. The mounting surfaces 1110 of the two power assemblies 11 are arranged opposite to each other and are electrically connected to each other. The package bodies 113 of the two power assemblies 11 are connected. The drive board 12 is arranged between the two power assemblies 11 and is electrically connected to at least one of the power assemblies 11. It can be understood that the drive board 12 can be embedded in the package body 113 of any one of these power assemblies 11, or the drive board 12 can be embedded between the package bodies 113 of these two power assemblies 11. Specifically, a part of the drive board 12 is embedded in the package body 113 of one power assembly 11, and the other part is embedded in the package body 113 of the other power assembly 11.

[0073] In this embodiment, the drive board 12 is embedded between the two power assemblies 11, so that the distance between the drive board 12 and the power chips 112 of the two power assemblies 11 is shortened, and the connection line between the drive board 12 and the power chips 112 of the two power assemblies 11 is further shortened. Thereby, the parasitic parameters of the connection line are effectively reduced, and the electrical performance of the power module 10 is improved. Also, the surfaces of the metal layers a3 of the two power assemblies 11 on the side opposite to the drive board 12 are both exposed from the package bodies 113, dissipating heat related to the power chips 112 corresponding to the two power assemblies 11. Thereby, the heat dissipation efficiency of the power chips 112 is improved, and the electrical performance of the power module 10 is effectively improved.

[0074] In this embodiment, as shown in FIG. 7, for ease of distinction, the two power assemblies 11 are designated as power assembly 11a and power assembly 11b, and the power assembly 11a is electrically connected to the drive board 12. Specifically, the power chip 112 of the power assembly 11a is connected to the drive chip 123 on the drive board 12 via the lead frame 15. To be sure, the power chip 112 of the power assembly 11a may instead be connected to the drive chip 123 on the drive board 12 using a conductive structure such as a lead or a metal bar, for example. In another embodiment, the drive board 12 may instead be electrically connected to the power chips 112 of the two power assemblies 11. Further, the drive board 12 may be connected to the power assembly 11a and the power assembly 11b in the same manner or in different manners.

[0075] The power module 10 includes a conductive bar 17 and pins 114. Both ends of the conductive bar 17 are respectively connected to the mounting surface 1110 of the power assembly 11a corresponding to the conductive bar 17 and the mounting surface 1110 of the power assembly 11b corresponding to the conductive bar 17. Specifically, both ends of the conductive bar 17 are respectively connected to the second line a22 of the power assembly 11a corresponding to the conductive bar 17 and the second line a22 of the power assembly 11b corresponding to the conductive bar 17, and are respectively electrically connected to the power chip 112 of the power assembly 11a and the power chip 112 of the power assembly 11b. One end of the pin 114 is fixed to the conductive bar 17 of the second line a22 of the power assembly 11a, and the other end of the pin 114 extends outward from the side of the package body 113 of the power assembly 11a and / or the package body 113 of the power assembly 11b and is connected to a related external device such as a circuit board. As shown in FIG. 7, there are two conductive bars 17 and two pins 114. The two conductive bars 17 are respectively located on both sides of the two power chips 112, and the two pins 114 respectively extend outward from the package body 113 from both sides of the package body 113. In this application, the conductive bar 17 is configured to realize the electrical connection between the power assembly 11a and the power assembly 11b, and the pin 114 is configured to connect the power assembly 11a and the power assembly 11b to an external device. Certainly, in another embodiment, the number and specific structure of the pins 114 and the conductive bars 17 are not limited to the above description.

[0076] In this embodiment, the lead frame 15 is used to connect two power chips 112 of the power assembly 11a to each other and connect these power chips 112 to the conductive bar 17. Leads are used to connect two power chips 112 of the power assembly 11b to each other and connect these power chips 112 to the conductive bar 17. Certainly, leads or other conductive structures may be used instead to connect two power chips 112 of the power assembly 11a to each other and connect these power chips 112 to the conductive bar 17. The lead frame 15 or other conductive structures may be used instead to connect two power chips 112 of the power assembly 11b to each other and connect these power chips 112 to the conductive bar 17.

[0077] By integrating the package body 113 of the power assembly 11a and the package body 113 of the power assembly 11b, the connection strength of the packaged structure 13 including the power assembly 11a, the power assembly 11b, and the drive board 12 is increased. Specifically, by using the plastic packaging process, an integrally formed package body 113 is formed by the package body 113 of the power assembly 11a and the package body 113 of the power assembly 11b. Certainly, the package body 113 of the power assembly 11a and the package body 113 of the power assembly 11b may be formed by using the housing packaging process instead.

[0078] The protection scope of this application is not limited to the first embodiment to the fourth embodiment, and any combination of the first embodiment to the fourth embodiment is also within the protection scope of this application. That is, the above-mentioned multiple embodiments may be combined according to actual requirements instead.

[0079] FIG. 8 is a schematic flowchart of the manufacturing method of the power module shown in FIG. 3. As shown in FIG. 8, the manufacturing method of the power module includes S110 - S130.

[0080] S110: Prepare a first power board including a substrate 111 and a power chip 112 disposed on the mounting surface 1110 of the substrate 111.

[0081] Specifically, as shown in FIGS. 9 - 12, the specific steps for preparing the first power board 11c are as follows: First, as shown in FIG. 9, the substrate 111 is prepared. The substrate 111 includes a support plate a1, a line layer a2, and a metal layer a3. The line layer a2 and the metal layer a3 are respectively formed on two opposite surfaces of the support plate a1. By having the line layer a2 and the metal layer a3 located on two surfaces of the support plate a1 respectively, the flatness of the support plate a1 is ensured and warping of the support plate a1 is prevented. The surface of the line layer a2 on the side opposite to the support plate a1 is the mounting surface 1110, that is, a power chip is disposed on the surface of the line layer a2 on the side opposite to the support plate a1. The surface of the substrate 111 on the side opposite to the power chip is the back surface 1111, that is, the surface of the metal layer a3 on the side opposite to the support plate a1 is the back surface 1111. The line layer a2 includes a first line a21 and a second line a22. The second line a22 is located on both sides of the first line a21. The surfaces of the first line a21 and the second line a22 on the side opposite to the support plate a1 together constitute the mounting surface 1110. It is certain that in another embodiment, the structure of the line layer a2 is not limited to the above - described structure, and the specific structure of the line layer a2 can be configured according to the connection requirements of the power chip.

[0082] In this embodiment, the support plate a1 can be made of an insulating and heat-dissipating material such as ceramic. The ceramic can be, for example, a ceramic material such as aluminum oxide, silicon nitride, or aluminum nitride. The ceramic material has a good heat dissipation effect and can quickly dissipate the heat related to the power chip disposed on the substrate 111 in subsequent processes. The line layer a2 and the metal layer a3 are made of a metal material such as, for example, copper, nickel, or aluminum material, can quickly dissipate the heat related to the power chip disposed on the substrate 111 in subsequent processes, and further can effectively increase the strength of the substrate 111. The line layer a2 and the metal layer a3 may be made of the same material or different materials. Also, the line layer a2 is further configured to realize an electrical connection between the power chip disposed on the substrate 111 and another line in subsequent processes. To be sure, in another embodiment, the support plate a1 may alternatively be made of other insulating materials.

[0083] Next, as shown in FIG. 10, a power chip 112 is prepared. The power chip 112 can be an insulated gate bipolar transistor (IGBT), a metal oxide semiconductor field effect transistor (MOSFET), and / or a diode. To be sure, in another embodiment, the power chip 112 may be substrate 111 prepared before. Alternatively, the substrate 111 and the power chip 112 may be prepared simultaneously.

[0084] Next, the power chip 112 is placed on the mounting surface 1110 of the substrate 111. Specifically, solder is printed on the first line a21, and then the power chip 112 is welded to the first line a21. In this embodiment, there are two power chips 112. The two power chips 112 are arranged on the first line a21 at intervals. To be sure, in another embodiment, one or more power chips 112 may be welded to the first line a21 instead. Alternatively, the power chip 112 may be fixed to the first line a21 by welding, bonding, or the like based on different conditions. For example, when it is necessary to electrically connect the power chip 112 to the first line a21, the power chip 112 can be fixed to the first line a21 by welding. When it is not necessary to electrically connect the power chip 112 to the first line a21, the power chip 112 can be fixed to the first line a21 by other methods such as bonding.

[0085] When the power chip 112 is placed on the mounting surface 1110 of the substrate 111, the pins 114 are fixed to the mounting surface 1110. First, solder is printed on both the first line a21 and the second line a22. Then, the power chip 112 is welded to the first line a21, and at the same time, the pins 114 are welded to the second line a22. Specifically, there are two pins 114, and the two pins 114 are welded to the second line a22 on both sides of the two power chips 112, respectively. In this embodiment, the pins 114 are perpendicular to the mounting surface 1110. Alternatively, the pins 114 may be fixed to the second line a corresponding to the pins 114 by welding using solder paste, ultrasonic welding, silver sintering, or the like. The shape of the pins 114 can be a cylindrical shape, an elliptical cylindrical shape, a rectangular parallelepiped shape, a polygonal shape, or the like. The shapes of the two pins 114 may be the same or different. The material of the pins 114 can be a metal or alloy with good electrical conductivity, such as Cu, Ag, or Al, for example. To be sure, the number and arrangement of the pins 114 can be arranged according to actual requirements instead. Alternatively, the pins 114 may not be perpendicular to the mounting surface 1110.

[0086] In this embodiment, the power chip 112 and the pins 114 are simultaneously attached to the mounting surface 1110. This helps to reduce the manufacturing process of the power module, reduce the production cost, and improve the production efficiency of the power module. In another embodiment, instead, the power chip 112 may be attached to the mounting surface 1110 before the pins 114, or the pins 114 may be attached to the mounting surface 1110 before the power chip 112.

[0087] Next, as shown in FIGS. 11 and 12, a conductor 15 electrically connected to the power chip 112 is formed on the surface of the power chip 112 on the side opposite to the mounting surface 1110, and the conductor 15 is configured to electrically connect the power chip 112 to related elements to be attached in a subsequent process. Specifically, the process of forming the conductor 15 can be implemented in a plurality of ways. Details will be described as follows.

[0088] In one implementation, as shown in FIG. 11, when the conductor is the copper bar 15, before the conductor 15 is formed on the surface of the power chip 112 on the side opposite to the mounting surface 1110, first, two power chips 112 are electrically connected to each other, and the power chip 112 is electrically connected to the pin 114 corresponding to the power chip 112. The two power chips 112 are connected to each other via a lead, and the power chip 112 is indirectly electrically connected to the pin 114 corresponding to the power chip 112. Specifically, by connecting a lead between the second line a22 and the power chip 112, the power chip 112 is indirectly electrically connected to the pin 114 corresponding to the power chip 112. The lead connection process is mature and simple and has a low cost. Certainly, in another embodiment, for example, a connection structure such as a lead frame may be used instead to connect the two power chips 112 to each other and connect the power chip 112 to the pin 114 corresponding to the power chip 112. Next, one end of the copper bar 15 is fixed to the surface of the power chip 112 on the side opposite to the mounting surface 1110 and is electrically connected to the power chip 112. The number of copper bars 15 matches the number of power chips 112, and one copper bar 15 corresponds to one power chip 112. Certainly, in another embodiment, the conductor 15 may be connected using another conductive structure such as a lead instead.

[0089] In another implementation, as shown in FIG. 12, when the conductor is the lead frame 15, the lead frame 15 is provided. The lead frame 15 includes a first terminal 151, a second terminal 152, and a third terminal 153 that are connected to each other, and the first terminal 151 is electrically connected to the second terminal 152 and the third terminal 153. In this embodiment, there are two lead frames 15. The first terminal 151 of the lead frame 15 is electrically connected to the power chip 112 corresponding to the lead frame 15, and the third terminal 153 is connected to the second line a22 corresponding to the lead frame 15, so that the lead frame 15 is connected to the pin 114 corresponding to the lead frame 15 via the second line a22. The second terminal 152 is configured to be connected to related elements in a subsequent process. Further, the two power chips 112 can be electrically connected to each other via the lead frame 15.

[0090] When the conductor is the lead frame 15, the lead frame 15 realizes both the electrical connection between the pin 114 and the power chip 112 and the electrical connection between the two power chips 112. Therefore, there is no need to introduce additional leads to connect the power chip 112 and the pin 114 and to connect the two power chips 112 to each other. Accordingly, the structure of the power module becomes simpler, the manufacturing process of the power module is reduced, and the production efficiency of the power module is improved. Also, compared with leads, the lead frame 15 has a stronger current-carrying capacity and smaller parasitic parameters, and therefore, the heat dissipation effect of the power chip 112 can be further improved.

[0091] Surely, in another embodiment, as shown in FIG. 13, it is not necessary to form a conductor on the surface of the power chip 112 on the side opposite to the mounting surface 1110. Instead, leads are used to directly connect the power chip 112 to the pin 114 and to connect the two power chips 112 to each other. Alternatively, other conductive structures are used to directly connect the power chip 112 to the pin 114 and to connect the two power chips 112 to each other.

[0092] S120: Prepare the drive board 12, place the drive board 12 on the side of the power chip 112 opposite to the mounting surface 1110, and electrically connect the drive board 12 to the power chip 112 to form the structure 13a to be packaged.

[0093] Specifically, as shown in FIGS. 14-16, first, the drive board 12 is prepared. In this embodiment, as shown in FIG. 14, the drive board 12 includes a central region 121 and an edge region 122 surrounding the central region 121. Electronic elements such as a drive chip 123, a resistor 124, a capacitor, and an optical coupler are arranged in the central region 121 to form a drive circuit. The drive board 12 further includes a through hole 125 and a via 126. The through hole 125 is located in the central region 121, and the via 126 is located in the edge region 122. Certainly, in another embodiment, small electronic elements such as the resistor 124, the capacitor, and the optical coupler may be partially arranged in the edge region 122 instead. Alternatively, the drive board 12 may include only the central region 121, that is, the drive board 12 may not include the edge region 122.

[0094] Next, the drive board 12 is placed on the side of the power chip 112 opposite to the mounting surface 1110, and the drive board 12 is electrically connected to the power chip 112 to form the structure 13a to be packaged. Specifically, the drive board 12 is disposed near the end of the pin 114 electrically connected to the power chip 112 and between both ends of the pin 114. By requiring the drive board 12 to be disposed near the end of the pin 114 electrically connected to the power chip 112, it is ensured that the distance between the drive board 12 and the power chip 112 is sufficiently short, whereby the parasitic parameters of the connection line between the drive board 12 and the power chip 112 are sufficiently small, and the electrical performance of the power module is effectively improved.

[0095] Specifically, this process can be implemented in multiple ways. In one implementation, as shown in FIGS. 14 and 15, in a scenario where a copper bar 15 or a lead frame 15 is disposed on the surface of the power chip 112 opposite to the mounting surface 1110, first, the drive board 12 is disposed at the end of the copper bar 15 opposite to the power chip 112 or at the second terminal 152 of the lead frame 15. The central region 121 is disposed opposite to the first power board 11c, and the pin 114 passes through the through hole 125 of the drive board 12 and is connected to the drive board 12 in an insulated manner. Next, by welding the end of the copper bar 15 opposite to the power chip 112 or the second terminal 152 of the lead frame 15 to the drive board 12, the drive chip 123 on the drive board 12 is electrically connected to the power chip 112 via the conductor 15, thereby forming the structure 13a to be packaged.

[0096] In this implementation, the length of the copper bar 15 is equal to the distance between the drive board 12 and the power chip 112. It can be understood that the length direction of the copper bar 15 is the direction of the current flow in the copper bar 15. Therefore, the length of the copper bar 15 is the shortest, that is, the connection line between the drive board 12 and the power chip 112 is the shortest. Thereby, the parasitic parameters of the connection line of the power module are effectively reduced, and the electrical performance of the power module is improved.

[0097] In another implementation, as shown in FIG. 16, in a scenario where a copper bar 15 or a lead frame 15 is not disposed on the surface of the power chip 112 opposite to the mounting surface 1110, first, the drive board 12 is disposed on the side of the power chip 112 opposite to the mounting surface 1110. The central region 121 is disposed opposite to the first power board 11c, and the pin 114 passes through the through hole 125 of the drive board 12. Next, by electrically connecting the hole wall of the through hole 125 to the pin 114, the drive chip 123 on the drive board 12 is electrically connected to the power chip 112 via the pin 114, thereby forming the structure 13a to be packaged.

[0098] In another embodiment, the drive board 12 includes only the central region 121, a copper bar or a lead frame is disposed on the surface of the power chip 112 opposite to the mounting surface 1110, and the pins 114 are not perpendicular to the mounting surface 1110. In this scenario, as shown in FIG. 17, an example in which the lead frame 15 is disposed on the surface of the power chip 112 opposite to the mounting surface 1110 is used for the description in FIG. 17. First, the drive board 12 is disposed on the second terminal 152 of the lead frame 15, and the central region 121 is located between the two pins 114 and is disposed opposite to the first power board 11c. Next, by welding the second terminal 152 of the lead frame 15 to the drive board 12, the drive chip 123 on the drive board 12 is electrically connected to the power chip 112 through the lead frame 15. Finally, a second power board 11d is prepared. The structure of the second power board 11d is basically the same as that of the first power board 11c. The second power board 11d is disposed on the side of the drive board 12 opposite to the first power board 11c and is electrically connected to the first power board 11c to form the structure 13a to be packaged. Specifically, the mounting surface 1110 of the second power board 11d is disposed opposite to the mounting surface 1110 of the first power board 11c. That is, the first power board 11c and the second power board 11d are symmetrically disposed on both sides of the drive board 12. It is certain that the arrangement methods of the pins 114, the drive board 12, the first power board, and the second power board are not limited to the above description. Instead, other structures other than the pins 114 may be used to connect the power chip 112 to the circuit board.

[0099] S130: Package the structure 13a to be packaged using the package body 113 to form a power module.

[0100] Specifically, as shown in FIGS. 18 and 19, in this embodiment, the structure 13a to be packaged is packaged using a plastic packaging process. The structure 13a to be packaged can be the structure 13a to be packaged shown in FIGS. 14, 15, 16, and 17. Hereinafter, an example in which the structure 13a to be packaged is the structure 13a to be packaged shown in FIG. 14 will be used for the purpose of explanation. Specifically, first, the structure 13a to be packaged is placed in a packaging mold. The end of the pin 114 on the side far from the power chip 112 extends outside the packaging mold. An avoidance structure is disposed in the packaging mold. The avoidance structure is placed on the surface of the edge region 122 of the drive board 12 on the side opposite to the power chip 112, passes through the via of the edge region 122, and extends toward the surface where the back surface 1111 of the substrate 111 is located. Next, the packaging mold is filled with a packaging body 113. The packaging body 113 can be made of a plastic material such as an epoxy resin, for example. After being cured, the packaging body 113, together with the structure 13a to be packaged, forms a packaged structure 13, and the power module 10 is formed. Finally, the packaging mold is removed. In this embodiment, the power module 10 formed using the plastic packaging process has good sealing performance, and therefore, the moisture resistance and reliability of the power module 10 can be improved.

[0101] In this embodiment, the package body 113 is packaged in the region from the back surface 1111 of the substrate 111 to the side of the drive board 12 on the side opposite to the power chip 112. The end of the pin 114 far from the power chip 112 is exposed from the package body 113 so as to be electrically connected to the associated external device. The back surface 1111 of the substrate 111 is exposed from the package body 113. Since the back surface 1111 of the metal layer a3 is exposed from the package body 113, the metal layer a3 can effectively transfer the heat of the power chip 112 to the outside, thereby improving the heat dissipation efficiency of the power chip 112. Further, the formed packaged structure 13 includes the via 126 formed by the above avoidance structure avoiding the package body 113 and the mounting hole 131 of the package body 113. Through the mounting hole 131, the associated components are connected to the packaged structure 13. The surface of the edge region 122 on the side opposite to the power chip 112 is exposed from the package body 113, whereby the fitting between the power chip 112 and the related structure becomes easy.

[0102] In the direction perpendicular to the mounting surface 1110, the distance between the drive board 12 and the power chip 112 is smaller than the distance between the drive board 12 and the surface of the package body 113 on the side opposite to the mounting surface 1110. In this embodiment, by requiring that the distance between the drive board 12 and the power chip 112 is smaller than the distance between the drive board 12 and the surface of the package body 113 on the side opposite to the mounting surface 1110, it is ensured that the distance between the drive board 12 and the power chip 112 is sufficiently short, whereby it is ensured that the parasitic parameters of the connection line between the drive board 12 and the power chip 112 are sufficiently small, and the electrical performance of the power module 10 is effectively improved.

[0103] Finally, as shown in FIG. 19, a heat sink 14 is fixed to the packaged structure 13, and the heat sink 14 contacts the back surface 1111 of the substrate 111 to improve the heat dissipation efficiency of the power chip 112. The specific process of fixing the heat sink 14 to the packaged structure 13 is as follows: A screw 132 passes through the mounting hole 131 from the surface of the edge region 122 on the side opposite to the power chip 112 and is tightened to the heat sink 14. The package body 113 is not arranged on the surface of the edge region 122 on the side opposite to the power chip 112. Therefore, the screw 132 is fixed through the surface of the edge region 122 on the side opposite to the power chip 112. Also, the package body 113 is made of a brittle material and is likely to be damaged under a large stress. Since the package body is not arranged in the edge region 122, the screw 132 directly transmits the tightening force to the drive board 12, thereby reducing the stress applied to the package body 113 and avoiding the risk of the package body 113 cracking by directly transmitting the tightening force of the screw 132 to the package body 113. To be sure, in another embodiment, the heat sink 14 may alternatively be fixed to the packaged structure 13 by using screws or other fixing methods. Or, the packaged structure 13 may alternatively be fixed to the heat sink 14 by other different connection methods such as bonding or clamping.

[0104] As shown in FIG. 20, in an embodiment where the structure 13a (FIG. 17) to be packaged includes the first power board 11c, the drive board 12, and the second power board 11d, after the structure 13a to be packaged is packaged by using the package body 113, the back surfaces 1111 of the substrates 111 of both the first power board 11c and the second power board 11d are exposed from the package body 113. Therefore, the substrates 111 of the first power board 11c and the second power board 11d are respectively connected to heat sinks corresponding to the back surfaces 1111 of the substrates 111 of the first power board 11c and the second power board 11d, and good heat dissipation for the power module 10 is realized.

[0105] In another embodiment, as shown in FIG. 21, the specific method of packaging the structure 13a to be packaged by using the package body 113 may instead be as follows: First, a package housing 16 is prepared, the structure 13a to be packaged is fixed within the package housing 16, and the end portions of the pins 114 on the side far from the mounting surface 1110 are exposed from the package housing 16. The structure 13a to be packaged may include (as shown in FIG. 21) the first power board 11c and the drive board 12, or alternatively, may include the first power board 11c, the drive board 12, and the second power board. Next, an adhesive is injected into the package housing 16 to fill the gaps within the package housing 16, thereby forming the package body 113. The package body 113, the structure 13a to be packaged, and the package housing 16 together constitute the packaged structure 13, thereby forming the power module 10. Specifically, silicone gel is injected into the package housing 16 to form the package body 113. In this embodiment, the package body 113 is formed using the housing packaging process. This process is simple, thereby effectively improving the production efficiency of the power module 10. In the scenario of this embodiment, the drive board 12 of the structure 13a to be packaged includes only the central region 121. To dissipate the heat related to the power module 10, a heat sink 14 is disposed on the package housing 16.

[0106] In the manufacturing method of the power module 10 in this application, the drive board 12 is arranged on the side of the power chip 112 opposite to the mounting surface 1110, and the drive board 12 is electrically connected to the power chip 112 to form the structure 13a to be packaged. Then, the structure 13a to be packaged is packaged to form the packaged structure 13. Specifically, by packaging the drive board 12 and the power chip 112 together, the distance between the drive board 12 and the power chip 112 can be shortened. Also, the connection line between the power chip 112 and the drive board 12 becomes shorter, thereby effectively reducing the parasitic parameters of the connection line between the power chip 112 and the drive board 12. That is, the parasitic parameters of the power module 10 are reduced, and the electrical performance of the power module 10 is improved. Further, the drive board 12 and the first power board 11c are packaged together. Compared with arranging the drive board 12 and the first power board 11c on the same plane, this can effectively reduce the planar area of the power module 10. When packaging the first power board 11c, in order to ensure the strength of the first power board 11c after packaging, the thickness of the first power board 11c after packaging is usually greater than 5 mm. This thickness is sufficient to enable the drive board 12 and the first power board 11c to be packaged together without increasing the thickness of the first power board 11c. That is, packaging the drive board 12 and the first power board 11c together does not affect the thickness obtained after packaging, thereby effectively improving the integration of the power module 10, reducing the package size is and reducing the cost of the power module 10.

[0107] The above description is only a specific implementation of this application and is not intended to limit the protection scope of this application. Any modifications or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application are within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

1. A power module having a power assembly and a drive board, wherein the power assembly has a substrate, a power chip, and a package body, the power chip is disposed on a mounting surface of the substrate, the package body packages the power chip on the substrate, the drive board is located on a surface side of the power chip opposite to the substrate and is partially disposed in the package body, and the drive board is electrically connected to the power chip, the drive board and the power assembly constitute a packaged structure, a surface of the substrate opposite to the power chip is a back surface, the back surface is exposed from the package body, and the power module further has a heat sink, the heat sink contacts the back surface and is fixed to the packaged structure, the drive board has a central region and an edge region surrounding the central region, the central region is disposed in the package body opposite to the power assembly, the packaged structure has a mounting hole, the mounting hole is located in the edge region and penetrates the drive board and the package body in a direction from the drive board to the power chip, and the heat sink is connected to the packaged structure through the mounting hole, a surface of the edge region opposite to the power chip is exposed from the package body, and a screw is tightened to the heat sink through the mounting hole from the exposed surface of the edge region, Power module.

2. The power module according to claim 1, wherein a distance between the drive board and the power chip is smaller than a distance between the drive board and a surface of the package body opposite to the substrate in a direction perpendicular to the mounting surface.

3. The power module according to claim 1 or 2, wherein the power assembly further has pins, the pins penetrate the drive board and a part of the package body, one end of the pins is disposed on the mounting surface and is electrically connected to the power chip, and the other end of the pins is exposed from the package body.

4. The power module according to claim 3, wherein the drive board is electrically connected to the power chip via the pins.

5. The power module according to claim 3, further comprising a conductor located between the power chip and the drive board, and the power chip is connected to the drive board via the conductor.

6. The power module according to claim 5, wherein the conductor is a copper bar, and both ends of the copper bar are electrically connected to the power chip and the drive board, respectively.

7. The power module according to claim 5, wherein the conductor is a lead frame, the lead frame has a first terminal and a second terminal connected to each other, the first terminal is electrically connected to the power chip, and the second terminal is electrically connected to the drive board.

8. The power module according to claim 7, wherein the lead frame further has a third terminal electrically connected to the first terminal, and the third terminal is electrically connected to the pins.

9. A converter having a circuit board and the power module according to any one of claims 1 to 8, wherein the power module is electrically connected to the circuit board.

10. An electronic device having the converter according to claim 9, wherein the converter is configured to convert an electrical signal of the electronic device.

11. Prepare a first power board, the first power board having a substrate and a power chip disposed on a mounting surface of the substrate. Prepare a drive board, dispose the drive board on a surface side of the power chip opposite to the substrate, and electrically connect the drive board to the power chip to form a structure to be packaged. The drive board has a central region disposed opposite to the first power board and an edge region surrounding the central region. By packaging the structure to be packaged using the package body, a packaged structure is formed. The package body is packaged in a region from the back surface of the substrate to the side of the drive board opposite to the power chip. The back surface of the substrate is the surface of the substrate on the side opposite to the mounting surface. The central region of the drive board is disposed within the package body, and the surface of the edge region of the drive board opposite to the power chip is exposed from the package body. The packaged structure has mounting holes that penetrate the edge region of the drive board and the package body. By tightening a screw through the mounting hole from the exposed surface of the edge region of the drive board to the heat sink, the heat sink is fixed to the packaged structure in contact with the back surface of the substrate. A method for manufacturing a power module having the above.

12. Before the step of disposing the drive board on the surface side of the power chip opposite to the substrate, the method further includes forming a conductor electrically connected to the power chip on the surface of the power chip opposite to the substrate. When the drive board is disposed on the surface side of the power chip opposite to the substrate, the drive board is electrically connected to the conductor. The method for manufacturing a power module according to claim 11.

13. The conductor is a copper bar, or the conductor is a lead frame. The method for manufacturing a power module according to claim 12.

14. Before the step of disposing the power chip on the mounting surface of the substrate, the method further includes fixing pins to the mounting surface. When the drive board is disposed on the surface side of the power chip opposite to the substrate, the pins penetrate the drive board. The method for manufacturing a power module according to any one of claims 11 to 13.

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