Power module, converter and electrical device

Abstract

The utility model provides a power module, a converter and an electrical device. The power module comprises a substrate, an electronic element, a first welding layer and a first frame, the substrate and the electronic element are oppositely arranged, and the first welding layer and the first frame are fixed between the substrate and the electronic element. The first frame encloses a first accommodating space. The first welding layer is located in the first containing space. When the power device is formed through a welding process, the first frame can play a role in blocking molten welding flux, the molten welding flux is prevented from overflowing out of a welding area, and then the problems that the electric connection reliability and the fixed connection reliability between the electronic element and the substrate are reduced, and short circuit occurs due to the fact that holes appear below the electronic element are solved.

Description

Technical Field

[0001] The present application relates to the field of semiconductor technology, and in particular to a power module, a converter and an electrical device. Background Art

[0002] Power modules are developing towards high integration and high density. High integration places higher requirements on the heat dissipation and reliability of the modules. During the assembly of power modules, welding is generally used to achieve connection. During the welding process, the molten solder easily overflows the welding area and flows to the non-welding area, resulting in insufficient solder in some parts of the welding area, forming voids in the welding layer, and poor connection reliability of the power module. Utility Model Content

[0003] The present application provides a power module, a converter and an electrical device.

[0004] In a first aspect, an embodiment of the present application provides a power module. The power module includes a substrate, an electronic component, a first solder layer, and a first frame. The substrate and the electronic component are arranged opposite to each other, and the first solder layer and the first frame are fixed between the substrate and the electronic component. The first frame includes a first end face, a second end face, and a first peripheral side face. The first end face and the second end face are arranged opposite to each other, and the first peripheral side face is connected between the first end face and the second end face. The first end face is connected to the substrate, and the second end face is connected to the electronic component. The first frame encloses a first accommodation space, and the first solder layer is located in the first accommodation space.

[0005] It is understandable that in this way, during the welding process, the first frame can block the molten solder, prevent the molten solder from overflowing the welding area, and thus prevent the formation of voids under the electronic component, resulting in reduced electrical connection reliability and fixed connection reliability between the electronic component and the substrate, and electrical short circuits and other problems. In addition, by setting the first frame, the thickness of the first solder layer can also be controlled so that the thickness of the first solder layer can be within a preset range, so that the connection reliability between the electronic component and the substrate is better, and the electrical connection reliability is better.

[0006] In a possible implementation manner, the melting point of the first frame is higher than the melting point of the first welding layer.

[0007] It is understandable that when the power device is formed by the reflow soldering process, the reflow soldering temperature can be set to be higher than the melting point of the material of the first solder layer and lower than the melting point of the material of the first frame. In this way, during the reflow soldering process, the first frame can be in a solid state, and the material used in the first solder layer (that is, the solder) is in a molten state, and the first frame can block the molten solder.

[0008] In a possible implementation, the first end face is parallel to the second end face. In this way, the first solder layer can have a better flatness, and the surface of the first solder layer facing the substrate and the surface facing the electronic component can be parallel, reducing the risk of the electronic component tilting, and the electrical connection reliability between the electronic component and the substrate is better.

[0009] In a possible implementation manner, the power module further includes a second welding layer, the second welding layer is connected between the first frame and the substrate, and the second welding layer and the first welding layer are an integrated structure.

[0010] It should be noted that the two components are integrated into an integrated structure through an integrated molding process, which means that in the process of forming one of the two components, the component is connected to the other component, and there is no need to connect the two components together through reprocessing (such as bonding, welding, snap connection, screw connection). For example, the first solder layer and the second solder layer form an integrated structure through a reflow soldering process. During the reflow soldering process, the solder in a molten state partially enters the gap between the first frame and the substrate, and forms a second solder layer after cooling. The first frame can be fixed by the second solder layer and the substrate.

[0011] In a possible implementation manner, the power module further includes a third welding layer, the third welding layer is connected between the first frame and the electronic component, and the third welding layer and the first welding layer are an integrated structure.

[0012] It is understandable that during the reflow soldering process, the molten solder partially enters the gap between the first frame and the electronic component and forms a third solder layer after cooling. The first frame can be fixedly connected to the electronic component via the third solder layer.

[0013] In a possible implementation manner, the thickness of the first frame is in a range of 200 micrometers to 300 micrometers.

[0014] It is understandable that by controlling the thickness of the first frame, the thickness of the first solder layer formed during the reflow soldering process can be controlled, so that the connection reliability between the electronic component and the first metal layer of the substrate is better, and the electrical connection reliability is better.

[0015] In a possible implementation manner, the first frame is made of copper, copper alloy, aluminum or aluminum alloy.

[0016] It is understandable that the first frame is made of conductive material, which can increase the electrical connection area between the electronic component and the substrate, which is conducive to reducing the electrical connection impedance between the electronic component and the substrate, and is conducive to reducing the energy consumption of the power device. The first frame can be made of copper, copper alloy, aluminum or aluminum alloy. The first frame has better strength and can be used for electrical signal transmission.

[0017] In a possible implementation manner, the first frame is rectangular, circular or triangular.

[0018] It is understandable that the shape of the first frame can be designed according to the shape of the area between the electronic component and the substrate that needs to be welded, so that during the reflow soldering process, the first frame can intercept the molten solder in the preset welding area.

[0019] In a possible implementation, the power module further includes a heat conductor, a fourth solder layer, and a second frame, wherein the fourth solder layer and the second frame are fixedly connected between the heat conductor and the substrate. The second frame includes a third end face, a fourth end face, and a second peripheral side face, wherein the third end face and the fourth end face are disposed opposite to each other, the second peripheral side face is connected between the third end face and the fourth end face, the third end face is connected to the heat conductor, the fourth end face is connected to the substrate, the second frame encloses a second accommodation space, and the fourth solder layer is located in the second accommodation space.

[0020] It is understandable that by providing a heat conductor, the heat dissipation of the electronic components during operation can be accelerated, which is beneficial to reducing the operating temperature of the electronic components and reducing the probability of failure of the power module due to excessively high temperature. The heat conductor is fixedly connected to the substrate through the fourth solder layer. The heat generated by the electronic components during operation can be transmitted to the heat conductor in sequence through the first solder layer, the first metal layer, the insulating layer, the second metal layer, and the fourth solder layer. The fourth solder layer can also be used to transfer heat. When the heat conductor is fixedly connected to the substrate through a welding process, by providing a second frame, the molten solder can be blocked to prevent the molten solder from overflowing the welding area and to prevent voids from appearing between the heat conductor and the substrate. The connection strength between the heat conductor and the substrate is better, and the heat conduction efficiency is better.

[0021] In a possible implementation manner, the melting point of the material of the second frame is higher than the melting point of the material of the fourth welding layer.

[0022] It is understandable that when the heat conductor is fixedly connected to the substrate through the reflow soldering process, the second frame can block the molten solder, prevent the molten solder from overflowing the soldering area, and prevent the formation of voids between the heat conductor and the substrate. The connection strength between the heat conductor and the substrate is better, and the heat conduction efficiency is better.

[0023] In a possible implementation manner, the electronic component is a chip, a resistor or a capacitor.

[0024] In a second aspect, an embodiment of the present application provides a converter, wherein the converter includes a driving board and a power module, wherein the power module is mounted on the driving board.

[0025] It can be understood that the power module is installed in the converter, the reliability angle of the power module is high, the converter is not prone to failure and has a longer service life.

[0026] In a third aspect, an embodiment of the present application provides an electrical device. The electrical device includes a housing and a converter, and the converter is mounted on the housing. In this way, the converter has a longer life, the electrical device is less likely to fail, and the service life of the electrical device is also longer. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to illustrate the technical solution of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be described below.

[0028] Figure 1 is a schematic diagram of an implementation of an electrical device provided in an embodiment of the present application;

[0029] Figure 2a yes Figure 1 A cross-sectional view of an embodiment of a converter shown in ;

[0030] Figure 2b yes Figure 2a An enlarged schematic diagram of an embodiment of the structure shown in A;

[0031] Figure 2c yes Figure 2b An enlarged schematic diagram of an embodiment of the structure shown in B;

[0032] Figure 3 yes Figure 2a A schematic diagram of the structure of the power module shown in FIG. 1 at another angle;

[0033] Figures 4 to 9 yes Figure 2a A schematic structural diagram of a method for manufacturing a power module in some embodiments;

[0034] Fig.10 yes Figure 2a The figure is a schematic flow chart of a method for manufacturing a power module in some embodiments. DETAILED DESCRIPTION

[0035] The embodiments of the present application are described below in conjunction with the drawings in the embodiments of the present application. The embodiments described herein with reference to the drawings are exemplary and intended to be used to explain the present application, and should not be understood as limiting the present application.

[0036] In the description of the embodiments of the present application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation" and "connection" should be understood in a broad sense. For example, "connection" can be a detachable connection or an undetachable connection; it can be a direct connection or an indirect connection through an intermediate medium. It should be understood that in the present application, "electrical connection" can be understood as the physical contact and electrical conduction of components; it can also be understood as the form in which different components in the circuit structure are connected through physical lines such as copper foil or wires on a printed circuit board (PCB) that can transmit electrical signals. "Connection" and "connected" can both refer to a mechanical connection relationship or a physical connection relationship. For example, A is connected to B or A is connected to B, which can mean that there is a fastening component (such as a screw, bolt, rivet, etc.) between A and B, or A and B are in contact with each other and A and B are difficult to separate.

[0037] Furthermore, the word "fixed" in this article should also be understood in a broad sense. For example, "fixed" can be directly fixed or indirectly fixed through an intermediate medium. Among them, "fixed connection" means that they are connected to each other and the relative position relationship after connection remains unchanged. The directional terms mentioned in the embodiments of the present application, such as "upper", "lower", etc., are only referenced to the directions of the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of the present application, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application. "Multiple" refers to two or more than two.

[0038] In the embodiments of the present application, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the features.

[0039] It is to be understood that the specific embodiments described herein are only used to explain the relevant application, rather than to limit the application. It should also be noted that, for ease of description, only the parts related to the present application are shown in the drawings.

[0040] Figure 11 is a schematic diagram of an implementation of an electrical device 1000 provided in an embodiment of the present application. The electrical device 1000 includes but is not limited to a wind turbine, a photovoltaic generator, an electric vehicle, a white appliance, and other electrical devices 1000 having a converter 100. The electrical device 1000 may also be a mobile phone, a tablet computer, a laptop computer, a vehicle-mounted device, a wearable device, a drone, a router, and other products. The electrical device 1000 may also be a power supply module, a communication signal transmitting base station, a network switching device, and other devices. In this embodiment, the electrical device 1000 is described as an electric vehicle as an example.

[0041] like Figure 1 As shown, the electrical device 1000 may include a converter 100 and a housing 200. The converter 100 is accommodated in the housing 200. The converter 100 includes but is not limited to a DC-AC converter, a DC-DC converter, and the like.

[0042] It is understandable that the converter 100 may have different functions in different usage scenarios. The number of converters 100 included in the electrical device 1000 may be multiple. For example, when the electrical device 1000 is an electric vehicle, the converter 100 may be located inside the vehicle, and the converter 100 may be electrically connected to the motor and the battery to convert the power between the motor and the battery. The converter 100 may also be used as a core device for DC and AC conversion in the motor control unit of the electric vehicle, outputting DC power to the battery of the electric vehicle, or converting DC power into AC power required for vehicle operation. When the electrical device 1000 is a photovoltaic generator, the converter 100 may be an inverter for converting the DC power generated by the photovoltaic module into AC power and transmitting it to the local load or the power grid. The converter 100 may also be an optimizer for real-time monitoring and control of parameters such as voltage, current and temperature of the photovoltaic module to achieve maximum power output and maximum energy utilization.

[0043] Figure 2a yes Figure 1 0 is a cross-sectional view of an embodiment of a converter 100 shown in FIG.

[0044] like Figure 2a As shown, the converter 100 may include a power module 10 and a driving board 20 , the power module 10 is mounted on the driving board 20 , and the driving board 20 is electrically connected to the power module 10 to control the power module 10 .

[0045] The power module 10 is a semiconductor device that can convert the voltage, current, frequency, etc. of the direct current output by a power source.

[0046] Among them, the driving board 20 can be electrically connected to the power module 10, and the driving board 20 can control the performance parameters of the alternating current output by the power module 10 to the motor according to the needs of the vehicle, such as voltage, current, frequency, etc., which are not strictly limited in this embodiment.

[0047] Figure 2b yes Figure 2a An enlarged schematic diagram of an embodiment of the structure shown in FIG.

[0048] like Figure 2a and Figure 2b As shown, the power module 10 may include a substrate 1, an electronic component 2, a first solder layer 3 and a first frame 4. The electronic component 2 is fixed on the substrate 1. The first solder layer 3 and the first frame 4 are fixed between the electronic component 2 and the substrate 1. The first solder layer 3 is used for fixed connection and electrical connection between the substrate 1 and the electronic component 2.

[0049] Exemplarily, the substrate 1 may include a first metal layer 11, an insulating layer 12, and a second metal layer 13. The insulating layer 12 is connected between the first metal layer 11 and the second metal layer 13. The insulating layer 12 may be used for insulation between the first metal layer 11 and the second metal layer 13.

[0050] In some embodiments, the material of the insulating layer 12 may be aluminum oxide ceramic or aluminum nitride ceramic, etc. In this way, the insulating layer 12 has the advantages of strong heat dissipation capability, good insulation performance and strong mechanical performance.

[0051] In some embodiments, the materials of the first metal layer 11 and the second metal layer 13 can both be copper. It is understood that copper has excellent electrical and thermal conductivity. In other embodiments, the materials of the first metal layer 11 and the second metal layer 13 are aluminum.

[0052] In some embodiments, the substrate 1 may be a direct bond copper (DBC) ceramic substrate or an active metal brazing (AMB) ceramic substrate.

[0053] Exemplarily, the electronic component 2 may be an active device such as a chip, or may be a passive device such as a capacitor, an inductor, or a resistor. For example, the electronic component 2 may be one or more of an insulated gate bipolar transistor (IGBT), a metal oxide semiconductor field effect transistor (MOSFET), and a fast recovery diode (FRD). Those skilled in the art can select the type and quantity of the electronic component 2 according to actual needs, and the present application does not limit this.

[0054] like Figure 2b As shown. The first frame 4 may include a first end face 41, a second end face 42 and a first peripheral side face 43, the first end face 41 and the second end face 42 are arranged opposite to each other, and the first peripheral side face 43 is connected between the first end face 41 and the second end face 42. The first end face 41 may be connected to the substrate 1. The second end face 42 may be connected to the electronic component 2. Exemplarily, the first end face 41 may be connected to the first metal layer 11.

[0055] The first frame 4 may enclose a first accommodation space 44. Exemplarily, the first accommodation space 44 may penetrate the first end surface 41 and the second end surface 42. The first accommodation space 44 may be spaced apart from the first peripheral side surface 43. The first solder layer 3 is located in the first accommodation space 44 and is connected between the first metal layer 11 of the substrate 1 and the electronic component 2. In this way, the electrical signal between the electronic component 2 and the first metal layer 11 of the substrate 1 can be transmitted through the first solder layer 3.

[0056] It is understandable that when the electronic component 2 is fixed to the substrate 1 by welding, the first frame 4 can block the molten solder, preventing the molten solder from overflowing the welding area, thereby preventing the formation of voids under the electronic component 2, resulting in reduced electrical connection reliability and fixed connection reliability between the electronic component 2 and the first metal layer 11, and causing electrical short circuits and other problems. In addition, by providing the first frame 4, the thickness of the first solder layer 3 can also be controlled, so that the thickness of the first solder layer 3 can be within a preset range, so that the connection reliability between the electronic component 2 and the first metal layer 11 of the substrate 1 is better, and the electrical connection reliability is better.

[0057] In one embodiment, the melting point of the material of the first frame 4 may be higher than the melting point of the material of the first solder layer 3. It is understandable that when the power device is formed by soldering through the reflow soldering process, the reflow soldering temperature may be set to be higher than the melting point of the material of the first solder layer 3 and lower than the melting point of the material of the first frame 4. In this way, during the reflow soldering process, the first frame 4 may be in a solid state, and the material (i.e., solder) used in the first solder layer 3 may be in a molten state, and the first frame 4 may block the molten solder to prevent the molten solder from overflowing the soldering area.

[0058] like Figure 2b As shown, the first end face 41 can be parallel to the second end face 42. In this way, the first solder layer 3 can have a good flatness, and the surface of the first solder layer 3 facing the substrate 1 and the surface facing the electronic component 2 can be parallel, reducing the risk of the electronic component 2 tilting, and the electrical connection reliability between the electronic component 2 and the substrate 1 is better. Exemplarily, the first end face 41 can be connected to the first metal layer 11 of the substrate 1.

[0059] It should be noted that the first end face 41 and the second end face 42 are parallel in terms of the current technological level, rather than an absolutely strict definition in the mathematical sense, and a small amount of deviation is allowed, and they can be approximately parallel or approximately perpendicular, etc. For example, there can be a slight angle between the first end face 41 and the second end face 42, and the angle can be between 0 degrees and 10 degrees.

[0060] The first frame 4 can be made of conductive material, so that the first frame 4 can also be used for electrical signal transmission between the electronic component 2 and the first metal layer 11. Compared with the solution in which the first frame 4 is made of insulating material, the first frame 4 is made of conductive material, which can increase the electrical connection area between the electronic component 2 and the first metal layer 11, which is beneficial to reduce the electrical connection impedance between the electronic component 2 and the first metal layer 11, and is beneficial to reduce the energy consumption of power devices. Exemplarily, the first frame 4 can be made of metal conductive material. For example, copper, copper alloy, aluminum or aluminum alloy. In this way, the strength of the first frame 4 is better and can be used for electrical signal transmission.

[0061] In one embodiment, the material of the first solder layer 3 may be tin-containing solder or silver solder. For example, the tin-containing solder may be SAC305, pure tin, SnSb5, SnSb10, high-lead solder, etc. The silver solder may be sintered silver, etc.

[0062] Figure 2c yes Figure 2b The structure shown in FIG. is an enlarged schematic diagram of an embodiment at B. It should be noted that, Figure 2c The first welding layer 3, the second welding layer 5 and the third welding layer 6 are illustrated by different filling patterns, which do not represent the actual size of the product. Figure 2cThe size ratio relationship between the components is not intended to limit the actual product of this application.

[0063] like Figure 2c As shown, the power module 10 may further include a second solder layer 5, and the second solder layer 5 may be connected between the first frame 4 and the substrate 1. The second solder layer 5 may be an integrated structure with the first solder layer 3. It should be noted that the two components are integrated by an integrated molding process, which means that in the process of forming one of the two components, the component is connected to the other component, and there is no need to connect the two components together by reprocessing (such as bonding, welding, snap connection, screw connection). For example, the first solder layer 3 and the second solder layer 5 form an integrated structure by a reflow soldering process. During the reflow soldering process, the solder in the molten state partially enters the gap between the first frame 4 and the substrate 1, and forms the second solder layer 5 after cooling. The first frame 4 can be fixed by the second solder layer 5 and the substrate 1. The material of the second solder layer 5 can be the same as that of the first solder layer 3.

[0064] In one embodiment, the power module 10 further includes a third solder layer 6, which can be connected between the first frame 4 and the electronic component 2. The third solder layer 6 and the first solder layer 3 are an integrated structure. It can be understood that during the reflow soldering process, the solder in a molten state partially enters the gap between the first frame 4 and the electronic component 2, and forms the third solder layer 6 after cooling. The first frame 4 can be fixedly connected to the electronic component 2 through the third solder layer 6. The material of the third solder layer 6 can be the same as that of the first solder layer 3.

[0065] In one embodiment, the thickness of the first frame 4 can be in the range of 200 microns to 300 microns. It is understandable that by controlling the thickness of the first frame 4, the thickness of the first solder layer 3 formed during the reflow soldering process can be controlled, so that the connection reliability between the electronic component 2 and the first metal layer 11 of the substrate 1 is better, and the electrical connection reliability is better.

[0066] In one embodiment, the thickness of the first welding layer 3 may also be in the range of 200 microns to 300 microns. It is understandable that the thickness of the first welding layer 3 may be greater than the thickness of the first frame 4. Exemplarily, the thickness of the first welding layer 3 may be equal to the sum of the thickness of the first frame 4, the thickness of the second welding layer 5, and the thickness of the third welding layer 6.

[0067] Figure 3 yes Figure 2a The schematic diagram of the structure of the power module 10 shown in FIG. 1 is a schematic diagram of the structure of the power module 10 at another angle. For ease of understanding, Figure 3 The first frame 4 and the first welding layer 3 are illustrated by dotted lines and fill patterns.

[0068] like Figure 3As shown, the shape of the first frame 4 can be as follows Figure 3 The rectangle shown in the figure may also be a circle, a triangle or other irregular shapes. It is understandable that the shape of the first frame 4 can be designed according to the shape of the area between the electronic component 2 and the substrate 1 that needs to be welded, so that during the welding process, the first frame 4 can intercept the molten solder in the preset welding area.

[0069] like Figure 2a and Figure 3 As shown, the power module 10 may further include a pin 99. The first metal layer 11 may include a first portion 111 and a second portion 112 that are spaced apart. The number of the first portion 111 and the number of the second portion 112 may both be multiple. Multiple first portions 111 are also spaced apart. Multiple second portions 112 are also spaced apart. The first portion 111 may be used to fix the electronic component 2. Exemplarily, the first portion 111 may be electrically connected to the second portion 112 via a bonding wire 98. In addition, the second portion 112 may be used to fix the pin 99 and electrically connect the pin 99. The pin 99 may be used to electrically connect to a device outside the power module 10 (e.g., a drive board 20 of the converter 100). In this way, the electronic component 2 may be electrically connected to an external device of the power module 10 via the first portion 111, the bonding wire 98, the second portion 112, and the pin 99.

[0070] It can be understood that the number of the first parts 111 of the present embodiment is multiple, and multiple first parts 111 can be correspondingly provided with multiple electronic components 2. In this way, the power module 10 can be provided with a large number of electronic components 2, or a large number of types of electronic components 2. When the number of the first parts 111 of the first metal layer 11 is multiple, the number of the first solder layer 3 and the first frame 4 can also be multiple. A first frame 4 and a first solder layer 3 constitute a connection structure, and at least one connection structure is provided between an electronic component 2 and a first part 111, which is used for electrical connection and fixed connection between the electronic component 2 and the first part 111.

[0071] In some embodiments, when there are multiple first frames 4 , the shapes and sizes of the multiple first frames 4 may be different.

[0072] In some embodiments, the pin 99 may also be fixed to the second portion 112 by reflow soldering. In this case, the power module 10 may further include a third frame and a seventh solder layer. The third frame and the seventh solder layer may be fixed between the pin 99 and the second portion 112. The configuration of the third frame and the seventh solder layer may refer to the configuration of the first solder layer 3 and the first frame 4, which will not be described in detail herein.

[0073] In other implementations, the power module may not be provided with pins 99, and the electrical signal may be transmitted through other electrical connection structures.

[0074] like Figure 2a As shown, the power module 10 may further include a heat conductor 7, a fourth solder layer 8 and a second frame 9. The fourth solder layer 8 and the second frame 9 are fixedly connected between the heat conductor 7 and the substrate 1. It can be understood that by providing the heat conductor 7, the heat dissipation of the electronic component 2 during operation can be accelerated, which is beneficial to reducing the operating temperature of the electronic component 2 and reducing the probability of failure of the power module 10 due to excessively high temperature.

[0075] In some embodiments, the heat conducting member 7 may be made of copper, so that the heat conducting member 7 has a higher heat conduction efficiency.

[0076] The second frame 9 may include a third end face 91, a fourth end face 92 and a second peripheral side face 93, wherein the third end face 91 and the fourth end face 92 are arranged opposite to each other, and the second peripheral side face 93 is connected between the third end face 91 and the fourth end face 92. The third end face 91 may be connected to the heat conductor 7. The fourth end face 92 may be connected to the substrate 1. Exemplarily, the fourth end face 92 may be connected to the second metal layer 13.

[0077] The second frame 9 encloses a second accommodating space 94. Exemplarily, the second accommodating space 94 can penetrate the third end face 91 and the fourth end face 92, and be spaced apart from the second peripheral side face 93. The fourth solder layer 8 is located in the second accommodating space 94. The heat conducting member 7 is fixedly connected to the substrate 1 through the fourth solder layer 8. The heat generated by the electronic component 2 during operation can be transmitted to the heat conducting member 7 through the first solder layer 3, the first metal layer 11, the insulating layer 12, the second metal layer 13, and the fourth solder layer 8 in sequence. The fourth solder layer 8 can also be used to transmit heat.

[0078] It is understandable that when the heat conductor 7 is fixedly connected to the substrate 1 through a welding process, the second frame 9 can be provided to block the molten solder, thereby preventing the molten solder from overflowing the welding area and preventing a cavity from appearing between the heat conductor 7 and the substrate 1. The connection strength between the heat conductor 7 and the substrate 1 is better, and the heat conduction efficiency is better.

[0079] In one embodiment, the melting point of the material of the second frame 9 can be higher than the melting point of the material of the fourth solder layer 8. It is understandable that when the heat conductor 7 is fixedly connected to the substrate 1 through the reflow soldering process, the reflow soldering temperature can be set to be higher than the melting point of the material of the fourth solder layer 8 and lower than the melting point of the material of the second frame 9. In this way, during the reflow soldering process, the second frame 9 can be in a solid state, the material used in the fourth solder layer 8 (that is, the solder) is in a molten state, and the second frame 9 can block the molten solder. Avoid the molten solder from overflowing the welding area and avoid the formation of voids between the heat conductor 7 and the substrate 1. The connection strength between the heat conductor and the substrate is better, and the heat conduction efficiency is better.

[0080] The shape of the second frame 9 can be rectangular, circular, triangular or other irregular shapes. The shape of the second frame 9 can be the same as or different from the shape of the first frame 4. It is understood that the shape of the second frame 9 can be designed according to the shape of the connection area between the heat conductor 7 and the substrate 1.

[0081] In one embodiment, the second frame 9 can be made of copper, copper alloy, aluminum or aluminum alloy. In this way, the strength of the second frame 9 is better. The material used by the second frame 9 can be the same as that of the first frame 4, or it can be different.

[0082] In one embodiment, the material of the fourth solder layer 8 may be a tin-containing solder or a silver solder. For example, the tin-containing solder may be SAC305, pure tin, SnSb5, SnSb10, high-lead solder, etc. The silver solder may be sintered silver, etc. The material of the fourth solder layer 8 may be the same as that of the first solder layer 3, or may be different.

[0083] In one embodiment, the power module 10 may further include a fifth welding layer. The fifth welding layer may be fixed between the second frame 9 and the second metal layer 13. The second frame 9 may be fixedly connected to the second metal layer 13 through the fifth welding layer. The fifth welding layer may be an integrated structure with the fourth welding layer 8. In some embodiments, the power module 10 may further include a sixth welding layer. The sixth welding layer may be fixed between the second frame 9 and the heat conductor 7. The second frame 9 may be fixedly connected to the heat conductor 7 through the sixth welding layer. The sixth welding layer may be an integrated structure with the fourth welding layer 8. It is understandable that the positional structural relationship between the fifth welding layer, the sixth welding layer and the fourth welding layer 8 may refer to the positional structural relationship between the second welding layer 5, the third welding layer 6 and the first welding layer 3, which will not be repeated here.

[0084] In one embodiment, the power module 10 may further include a heat sink (not shown). The heat sink is connected to the side of the heat conductor 7 away from the electronic component 2. The heat sink may be an air-cooled heat sink or a liquid-cooled heat sink. The heat conductor 7 transfers the heat generated by the electronic component 2 during operation to the heat sink, and the heat is taken away by the flowing water or wind in the heat sink.

[0085] In one embodiment, the heat sink and the heat conductor 7 may also be fixedly connected by welding. The connection method between the heat sink and the heat conductor 7 may also refer to the connection method between the substrate 1 and the heat conductor 7 .

[0086] The present application introduces the structure of several power modules 10 in combination with the accompanying drawings. The power module 10 includes a substrate 1, an electronic component 2, a first solder layer 3 and a first frame 4. The substrate 1 and the electronic component 2 are arranged opposite to each other, and the first solder layer 3 and the first frame 4 are fixed between the substrate 1 and the electronic component 2. The first frame 4 includes a first end face 41, a second end face 42 and a first peripheral side face 43. The first end face 41 and the second end face 42 are arranged opposite to each other, and the first peripheral side face 43 is connected between the first end face 41 and the second end face 42. The first end face 41 is connected to the substrate 1, and the second end face 42 is connected to the electronic component 2. The first frame 4 encloses a first accommodating space 44, and the first solder layer 3 is located in the first accommodating space 44.

[0087] It is understandable that when the power device is formed by the welding process, the material (i.e., solder) used in the first welding layer 3 is in a molten state, and the first frame 4 can block the molten solder to prevent the molten solder from overflowing the welding area, thereby preventing the appearance of voids under the electronic component 2, resulting in reduced reliability of electrical connection and fixed connection between the electronic component 2 and the substrate 1, and causing electrical short circuits and other problems. In addition, by providing the first frame 4, the thickness of the first welding layer 3 can also be controlled, so that the thickness of the first welding layer 3 can be within a preset range, so that the connection reliability between the electronic component 2 and the substrate 1 is better, and the electrical connection reliability is better.

[0088] Figures 4 to 9 yes Figure 2a The schematic diagram of the structure of the manufacturing method of the power module 10 in some embodiments is shown. Fig.10 yes Figure 2a The flowchart of the manufacturing method of the power module 10 in some embodiments is shown.

[0089] like Figures 4 to 10 As shown, in an embodiment of the present application, a method for manufacturing a power module 10 is provided, comprising:

[0090] Step S101: Figure 4 As shown, a heat conducting member 7 and a first solder 97 are provided, and the first solder 97 is placed on the heat conducting member 7;

[0091] Step S102: Figure 5 As shown, the second frame 9 is placed on the heat conducting member 7. The first solder 97 is located in the second accommodation space 94 of the second frame 9. The melting point of the material of the second frame 9 is higher than the melting point of the material of the first solder 97.

[0092] The second frame 9 may include a third end face 91, a fourth end face 92 and a second peripheral side face 93, the third end face 91 and the fourth end face 92 are arranged opposite to each other, and the second peripheral side face 93 is connected between the third end face 91 and the fourth end face 92. The third end face 91 may be connected to the heat conducting member 7. The second frame 9 encloses a second accommodating space 94. Exemplarily, the second accommodating space 94 runs through the third end face 91 and the fourth end face 92, and is spaced apart from the second peripheral side face 93.

[0093] Step S103: Figure 6 As shown, the substrate 1 is placed on a side of the first solder 97 and the second frame 9 away from the heat conducting member 7 .

[0094] Step S104: Figure 7 As shown, the second solder 96 is placed on a side of the substrate 1 away from the heat conducting member 7 .

[0095] Step S105: Figure 8 As shown, the first frame 4 is placed on the side of the substrate 1 away from the heat conducting member 7. The second solder 96 is located in the first accommodation space 44 of the first frame 4. The melting point of the material of the first frame 4 is higher than the melting point of the material of the second solder 96.

[0096] The first frame 4 may include a first end face 41, a second end face 42, and a first peripheral side face 43, the first end face 41 and the second end face 42 are arranged opposite to each other, and the first peripheral side face 43 is connected between the first end face 41 and the second end face 42. The first end face 41 may be connected to the substrate 1. The first frame 4 encloses a first accommodating space 44. Exemplarily, the first accommodating space 44 runs through the first end face 41 and the second end face 42, and is spaced apart from the first peripheral side face 43.

[0097] Step S106: Figure 8 and Fig. 9 As shown, the electronic component 2 is placed on the side of the second solder 96 and the first frame 4 away from the substrate 1. The electronic component 2, the first frame 4, the second solder 96, the substrate 1, the first solder 97, the second frame 9, and the heat conducting member 7 constitute a component 101 to be welded.

[0098] Step S107: soldering the workpiece 101 through a reflow soldering process to form Figure 2aThe power module 10 shown in FIG. The soldering temperature is higher than the melting point of the first solder 97 and the melting point of the second solder 96 , and lower than the melting point of the first frame 4 and the melting point of the second frame 9 .

[0099] The power module 10 may include an electronic component 2, a first solder layer 3, a fourth solder layer 8, a first frame 4, a second frame 9, a substrate 1, and a heat conductor 7. The first solder layer 3 is located in the first accommodating space 44 and connected between the electronic component 2 and the substrate 1. The second solder layer 5 is located in the second accommodating space 94 and connected between the heat conductor 7 and the substrate 1. The first solder layer 3 is formed by at least a portion of the second solder 96, and the fourth solder layer 8 is formed by at least a portion of the first solder 97.

[0100] It is understandable that during the reflow soldering process of the power module 10, a first frame 4 is provided around the second solder 96, and the reflow soldering temperature is set to be higher than the melting point of the second solder 96 and lower than the melting point of the first frame 4. During the soldering process, the first frame 4 can be in a solid state, and the second solder 96 is in a molten state. The first frame 4 can block the molten second solder 96, preventing the molten second solder 96 from overflowing the preset soldering area, thereby preventing a cavity from appearing under the electronic component 2, resulting in a decrease in the connection reliability between the electronic component 2 and the substrate 1, and causing electrical short circuits and other problems. Connection reliability includes electrical connection reliability and fixed connection reliability.

[0101] By providing the second frame 9, the reflow soldering temperature is set to be higher than the melting point of the first solder 97 and lower than the melting point of the second frame 9. This can block the molten first solder 97, prevent the molten first solder 97 from overflowing the soldering area, and prevent voids from appearing between the heat-conducting member 7 and the substrate 1. This makes the connection strength between the heat-conducting member 7 and the substrate 1 better, and the heat conduction efficiency better.

[0102] In some embodiments, the power module 10 may further include a second solder layer 5, which is connected between the first frame 4 and the substrate 1. The second solder layer 5 may be formed by a portion of the first solder 97. It is understood that during the reflow soldering process, a portion of the first solder 97 in a molten state enters the gap between the first frame 4 and the substrate 1, and forms the second solder layer 5 after cooling. The first frame 4 may be fixed by the second solder layer 5 and the substrate 1.

[0103] In some embodiments, when the power module 10 does not include the heat conductor 7 , the preparation steps S101 to S103 may be omitted, and in step 104 , a substrate 1 is directly provided, and the second solder 96 is placed on the substrate 1 .

[0104] In some embodiments, the order of placing the second frame 9 and the first solder 97 in step S101 and step S102 may also be interchanged, that is, first place the second frame 9 on the heat conducting member 7 , and then place the first solder 97 in the second frame 9 .

[0105] It can be understood that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other, and any combination of features in different embodiments is also within the protection scope of the present application. That is to say, the multiple embodiments described above can also be arbitrarily combined according to actual needs.

[0106] It is understood that all the above drawings are exemplary illustrations of the present application and do not represent the actual size of the product. Moreover, the size ratio relationship between the components in the drawings is not intended to limit the actual product of the present application.

[0107] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A power module (10), characterized in that: It comprises a substrate (1), an electronic component (2), a first solder layer (3) and a first frame (4), wherein the substrate (1) and the electronic component (2) are arranged opposite to each other, and the first solder layer (3) and the first frame (4) are fixed between the substrate (1) and the electronic component (2); The first frame (4) comprises a first end face (41), a second end face (42) and a first peripheral side face (43); the first end face (41) and the second end face (42) are arranged opposite to each other; the first peripheral side face (43) is connected between the first end face (41) and the second end face (42); the first end face (41) is connected to the substrate (1); the second end face (42) is connected to the electronic component (2); the first frame (4) encloses a first accommodating space (44); and the first solder layer (3) is located in the first accommodating space (44).

2. The power module (10) according to claim 1, characterized in that: The melting point of the material of the first frame (4) is higher than the melting point of the material of the first welding layer (3).

3. The power module (10) according to claim 1, characterized in that: The first end surface (41) and the second end surface (42) are parallel.

4. The power module (10) according to any one of claims 1 to 3, characterized in that: The power module (10) further comprises a second welding layer (5), wherein the second welding layer (5) is connected between the first frame (4) and the substrate (1), and the second welding layer (5) and the first welding layer (3) are an integrated structure.

5. The power module (10) according to any one of claims 1 to 3, characterized in that: The power module (10) further comprises a third welding layer (6), wherein the third welding layer (6) is connected between the first frame (4) and the electronic component (2), and the third welding layer (6) and the first welding layer (3) are an integrated structure.

6. The power module (10) according to any one of claims 1 to 3, characterized in that: The thickness of the first frame (4) is in the range of 200 micrometers to 300 micrometers.

7. The power module (10) according to any one of claims 1 to 3, characterized in that: The first frame (4) is made of copper, copper alloy, aluminum or aluminum alloy.

8. The power module (10) according to any one of claims 1 to 3, characterized in that: The first frame (4) is rectangular, circular or triangular.

9. The power module (10) according to any one of claims 1 to 3, characterized in that: The power module (10) further comprises a heat conducting member (7), a fourth welding layer (8) and a second frame (9), wherein the fourth welding layer (8) and the second frame (9) are fixedly connected between the heat conducting member (7) and the substrate (1); The second frame (9) comprises a third end face (91), a fourth end face (92) and a second peripheral side face (93); the third end face (91) and the fourth end face (92) are arranged opposite to each other; the second peripheral side face (93) is connected between the third end face (91) and the fourth end face (92); the third end face (91) is connected to the heat conducting element (7); the fourth end face (92) is connected to the substrate (1); the second frame (9) encloses a second accommodating space (94); and the fourth welding layer (8) is located in the second accommodating space (94).

10. The power module (10) according to claim 9, characterized in that: The melting point of the material of the second frame (9) is higher than the melting point of the material of the fourth welding layer (8).

11. The power module (10) according to any one of claims 1 to 3, characterized in that: The electronic component (2) is a chip, a resistor or a capacitor.

12. A converter (100), characterized in that: It comprises a driving board (20) and a power module (10) according to any one of claims 1 to 11, wherein the power module (10) is mounted on the driving board (20).

13. An electrical device (1000), characterized in that: It comprises a housing (200) and the converter (100) according to claim 12, wherein the converter (100) is mounted on the housing (200).

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