Power module and vehicle-mounted inverter

Abstract

The utility model discloses a power module, comprising a substrate, the substrate comprises a substrate body, one side surface of the substrate body is provided with a first metal layer; the conductor cushion block is connected to the first metal layer; the first end of the signal pin is connected to the conductor cushion block; the power semiconductor is electrically connected with the conductor cushion block and the signal pin; and the first metal layer, the conductor cushion block, the signal pin and the power semiconductor are all arranged in the packaging body. The utility model further discloses a vehicle-mounted inverter which adopts the power module. According to the power module provided by the utility model, the conductor cushion block is arranged between the signal pin and the substrate, and the conductor cushion block is used as a part of a signal loop, so that the length of the signal pin is shortened, the equivalent sectional area of the signal loop is increased, the problems of large parasitic inductance and slow switching speed are avoided, and the performance of the power module is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of electronic devices, in particular to a power module and a vehicle-mounted inverter. Background Art

[0002] A power module is a module that is formed by combining power electronic devices according to certain functions and then encapsulating them. Compared with traditional IGBT power modules, silicon carbide power modules, as a new generation of wide bandgap semiconductors, theoretically have the advantages of fast switching speed, low loss, and support for high voltage and high current.

[0003] The specific structure of the existing silicon carbide power module is as follows Figure 1 As shown in the figure, a is sealant, b is signal pin, and c is plastic shell. The module welds the signal pin base on the surface of the copper-clad substrate, plugs the signal pin, and uses glue sealing to seal between the surface of the copper-clad substrate and the plastic shell. The poor heat resistance, easy moisture absorption, and insufficient structural strength of this structure restrict the performance and durability of the power module. Utility Model Content

[0004] In order to solve the above problems, one of the purposes of the present invention is to provide a power module, and its technical solution is as follows:

[0005] A power module, comprising:

[0006] A substrate, the substrate comprising a substrate body, a first metal layer being disposed on one side surface of the substrate body;

[0007] A conductor pad, wherein the conductor pad is connected to the first metal layer by a first fixed connection method using a known process;

[0008] A signal pin, a first end of which is connected to the conductor pad by a second fixed connection method of a known process;

[0009] A power semiconductor, the power semiconductor being electrically connected to the conductor pad and the signal pin;

[0010] The first metal layer, the conductor pad, the signal needle and the power semiconductor are all arranged in the package body, and the second end of the signal needle is exposed at the first surface of the package body.

[0011] In some preferred embodiments, a second metal layer is disposed on the substrate body, and the second metal layer is located on the other side surface of the substrate body opposite to the first metal layer, and the second metal layer is exposed on the surface of the package body.

[0012] In some preferred embodiments, the first surface is opposite to the first metal layer.

[0013] In some preferred embodiments, the package body is made of an encapsulation material, and the encapsulation material includes or does not include epoxy molding compound.

[0014] In some preferred embodiments, a gap is formed on the package body, and the conductor pad and the signal needle are located in the gap.

[0015] In some preferred embodiments, the first fixed connection method is sintering and / or welding; the second fixed connection method is plugging and / or sintering and / or welding and / or the signal needle contacts the conductor pad, and the signal needle is fixed to the package body.

[0016] In some preferred embodiments, the substrate body is an insulating substrate, a third metal layer is disposed on the substrate body, and the third metal layer is connected to the power semiconductor by a third fixed connection method of a known process.

[0017] In some preferred embodiments, the third metal layer is independent of the first metal layer, and the power semiconductor is connected to the first metal layer via a copper clip and / or a bonding wire.

[0018] In some preferred embodiments, the third metal layer is formed integrally with the first metal layer.

[0019] In some preferred embodiments, the power semiconductor is an IGBT or a SiC semiconductor chip, and the power semiconductor adopts a single-tube packaging structure, a full-bridge packaging structure, or a half-bridge packaging structure.

[0020] A second object of the present utility model is to provide a vehicle-mounted inverter, which adopts any of the power modules described above.

[0021] Beneficial effects: The power module of the utility model is provided with a conductor pad between the signal pin and the substrate. The conductor pad, as a part of the signal loop, shortens the length of the signal pin, increases the equivalent cross-sectional area of ​​the signal loop, reduces the parasitic inductance, thereby increasing the switching speed and improving the performance of the power module; the encapsulation material is directly used as the packaging body, avoiding the defects of the glue-filling sealing method that is not heat-resistant and easy to get wet; the signal pin and the conductor pad are welded to make its structure more reliable. Compared with the prior art, the power module of the utility model not only improves the product performance, but also improves the product durability. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0023] Figure 1 It is a prior art structure diagram.

[0024] Figure 2 It is a structural schematic diagram of an embodiment of the utility model.

[0025] Figure 3 It is a structural schematic diagram of another embodiment of the utility model.

[0026] Figure 4 It is a schematic structural diagram of a substrate and a packaging body in an exploded state in one embodiment of the utility model.

[0027] The realization of the purpose, functional features and advantages of the utility model will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back...), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0030] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the utility model, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the utility model.

[0031] A power module, reference Figure 2-4 As shown, it includes a substrate 100, a package body 200, a conductor pad 300, a signal pin 400 and a power semiconductor 500. The substrate 100 includes a substrate body 101, and a first metal layer 102 is provided on one side surface of the substrate body 101. The conductor pad 300 is connected to the first metal layer 102 by a first fixed connection method of a known process, and one end of the signal pin 400 is connected to the conductor pad 300 by a second fixed connection method of a known process. The power semiconductor 500 is electrically connected to the conductor pad 300 and the signal pin 400 to form a signal loop.

[0032] The first metal layer 102, the conductor pad 300, the signal pin 400 and the power semiconductor 500 are all disposed in the package 200. The surface of the package 200 includes a first surface 201, and the second end of the signal pin 400 is exposed on the first surface 201 of the package 200.

[0033] In a specific implementation, the substrate body 101 may be located inside the package body 200 , or the substrate body 101 may be exposed on the surface of the package body 200 .

[0034] In this scheme, if Figure 2-3 As shown, the electrical signal loop of the power semiconductor 500 includes a first metal layer 102, a conductor pad 300 and a signal pin 400. The existence of the conductor pad 300 shortens the length of the signal pin 400 due to its thickness. At the same time, the conductor pad 300 increases the equivalent cross-sectional area of ​​the signal loop. This structural form increases the cross-sectional area of ​​the equivalent signal loop relative to the prior art, avoids the problems of large parasitic inductance and slow switching speed, and improves the performance of the power module. The conductor pad 300 is made of conductive materials, such as carbon materials and metal materials such as pure copper and molybdenum-copper alloy.

[0035] In some preferred embodiments, Figure 2As shown, a second metal layer 103 is disposed on the substrate body 101 , and the second metal layer 103 is located on the other side surface of the substrate body 101 opposite to the first metal layer 102 , and the second metal layer 102 is exposed on the surface of the package body 200 .

[0036] In some preferred embodiments, Figure 2 As shown, the first surface 201 is opposite to the first metal layer 102, so that the signal pin 400 is exposed from the package body 200 directly above the conductor pad 300. This structural form can fully utilize the space above the module and has the beneficial effect of improving the power density of the system.

[0037] In some preferred embodiments, Figure 2 As shown, the package body 200 is made of encapsulation materials, some of which include epoxy molding compounds, while others do not. The beneficial effect of directly using epoxy molding compounds for encapsulation is that it is not affected by the external environment (water vapor, temperature, pollution, etc.), and achieves composite advantages such as heat resistance, insulation, moisture resistance, pressure resistance, and support.

[0038] In some preferred embodiments, Figure 2 As shown, a gap 203 is formed on the package body 200, and the conductor pad 300 and the signal pin 400 are located in the gap 203. In a specific implementation, the conductor pad 300 is firstly arranged on the substrate 100, and then packaged to form the package body 200, and then the encapsulation material on the conductor pad 300 is removed to form the gap 203, and finally the signal pin 400 is connected to the conductor pad 300 through the gap 203.

[0039] In some preferred embodiments, the width of the conductor block 300 is greater than or equal to the width of the signal pin 400 , so as to facilitate connection with the signal pin 400 .

[0040] In some preferred embodiments, the overall width of the gap 203 is the same as the width of the corresponding conductor spacer 300 .

[0041] In some preferred embodiments, the substrate 100 is an insulating substrate, which includes AMB copper-clad ceramic substrates, direct bonded copper ceramic substrates (DBC), direct plated copper ceramic substrates (DPC), copper plate pressed and insulating film substrates, and the like.

[0042] In some preferred embodiments, the first fixing connection method is sintering and / or welding. Sintering specifically includes silver sintering and copper sintering, which are processes used for sintering electronic devices.

[0043] In some preferred embodiments, the second fixed connection method is plugging and / or sintering and / or welding and / or the signal pin 400 contacts the conductor pad 300, and the signal pin 400 is fixed to the package body 200. Sintering specifically includes processes for sintering electronic devices such as silver sintering and copper sintering. Plug-in is to set a socket on the conductor pad 300, and insert the signal pin 400 into the socket on the conductor pad 300. When the package body 200 is formed by encapsulation of an encapsulating material, the signal pin 400 can be fixedly packaged on the package body 200, and at the same time, the lower end of the signal pin 400 is in contact with the conductor pad 300, thereby achieving current conduction between the conductor pad 300 and the signal pin 400. The signal pin 400 is welded to the conductor pad 300, which has stronger structural reliability.

[0044] In some preferred embodiments, the substrate body 101 is an insulating substrate, a third metal layer 104 is disposed on the substrate body 101, and the third metal layer 104 is connected to the power semiconductor 500 by a third fixed connection method of a known process. The third fixed connection method is sintering and / or welding.

[0045] In some preferred embodiments, the third metal layer 104 is independent of the first metal layer 102, and the power semiconductor 500 is connected to the first metal layer 102 via a copper clip and / or a bonding wire. Figure 2 As shown, the power semiconductor 500 is connected to the first metal layer 102 via a bonding wire 600 , so that the potential of the signal pin 400 is consistent with the potential of the upper surface electrode of the power semiconductor 500 .

[0046] In some preferred embodiments, Figure 3 As shown, the third metal layer 104 is formed integrally with the first metal layer 102. The corresponding connecting components are eliminated, the structure is simpler, and it has stronger economical efficiency. At the same time, the potential of the signal pin 400 is consistent with the electrode on the lower surface of the power semiconductor 500.

[0047] In some preferred embodiments, Figure 2 As shown, the power semiconductor 500 is an IGBT or SiC semiconductor chip, and the power semiconductor 500 adopts a single-tube packaging structure or a full-bridge packaging structure or a half-bridge packaging structure.

[0048] A vehicle-mounted inverter comprises any one of the power modules described above.

[0049] The above description is only a preferred embodiment of the utility model, and does not limit the patent scope of the utility model. All equivalent structural changes made by using the contents of the utility model specification and drawings under the utility model concept, or directly / indirectly used in other related technical fields are included in the patent protection scope of the utility model.

Claims

1. A power module, characterized in that: include: A substrate (100), the substrate (100) comprising a substrate body (101), a first metal layer (102) being provided on a surface of one side of the substrate body (101); A conductor pad (300), wherein the conductor pad (300) is connected to the first metal layer (102) by a first fixed connection method of a known process; A signal pin (400), wherein a first end of the signal pin (400) is connected to the conductor pad (300) by a second fixed connection method of a known process; A power semiconductor (500), the power semiconductor (500) being electrically connected to the conductor pad (300) and the signal pin (400); A package (200), wherein the first metal layer (102), the conductor pad (300), the signal needle (400) and the power semiconductor (500) are all arranged in the package (200), and the second end of the signal needle (400) is exposed on the first surface (201) of the package (200).

2. The power module according to claim 1, characterized in that: A second metal layer (103) is disposed on the substrate body (101), and the second metal layer (103) is located on the other side surface of the substrate body (101) opposite to the first metal layer (102), and the second metal layer (103) is exposed on the surface of the package body (200).

3. The power module according to claim 1, characterized in that: The first surface (201) is opposite to the first metal layer (102).

4. The power module according to claim 1, characterized in that: The package body (200) is made of an encapsulation material, and the encapsulation material includes or does not include epoxy molding compound.

5. The power module according to claim 1, characterized in that: A gap (203) is formed on the package body (200), and the conductor pad (300) and the signal needle (400) are located in the gap (203).

6. The power module according to claim 1, characterized in that: The first fixed connection method is sintering and / or welding; the second fixed connection method is plugging and / or sintering and / or welding and / or the signal needle (400) contacts the conductor pad (300), and the signal needle (400) is fixed to the package body (200).

7. The power module according to claim 1, characterized in that: The substrate body (101) is an insulating substrate. A third metal layer (104) is provided on the substrate body (101). The third metal layer (104) is connected to the power semiconductor (500) by a third fixed connection method of a known process.

8. The power module according to claim 7, characterized in that: The third metal layer (104) and the first metal layer (102) are independent of each other, and the power semiconductor (500) is connected to the first metal layer (102) via a copper clip and / or a bonding wire.

9. The power module according to claim 7, characterized in that: The third metal layer (104) is formed integrally with the first metal layer (102).

10. The power module according to claim 1, characterized in that: The power semiconductor (500) is an IGBT or a SiC semiconductor chip, and the power semiconductor (500) adopts a single-tube packaging structure, a full-bridge packaging structure, or a half-bridge packaging structure.

11. A vehicle-mounted inverter, characterized in that: A power module as described in any one of claims 1 to 10 is used.

Images