Terminal structure for power module and power module

Abstract

The utility model discloses a terminal structure for a power module and the power module, the terminal structure comprises at least two stacked busbars, each busbar comprises: a main body having a first side edge and a second side edge opposite to each other; the connecting pin is located on the first side edge of the main body, one end of the connecting pin is connected with the main body, and the other end of the connecting pin is electrically connected with a power unit of the power module; the leading-out part is located on the second side edge of the main body and protrudes out of the second side edge, and the leading-out part and the main body are located on the same plane; wherein the connecting pins comprise at least two groups, and the two groups of connecting pins are symmetrically arranged on the first side edge of the main body; the main bodies of different busbars are located on different planes, the connecting pins of different busbars are transversely staggered, and the leading-out parts of different busbars are transversely staggered. According to the utility model, the size of the power module is obviously reduced, the layout of the power module is more compact, the cost is reduced, the leading-out path of the power module is changed, the current distribution of the power module is improved, the stray inductance of various commutation loops is reduced, and the electrical performance and the reliability of the power module are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductors, and more particularly to a terminal structure for a power module and a power module. Background Art

[0002] The power module is a new type of high-power power electronic device with the advantages of high current density, low saturation voltage and high voltage resistance. It is currently widely used in various fields such as production and life.

[0003] Power modules are power semiconductor devices that implement power conversion and control in power electronics systems. With the increasing integration and current density of power modules, conventional terminal structures are no longer able to meet their connection requirements. If the existing terminal structure is still used, it will significantly affect the switching characteristics and current waveform of the power module, thereby affecting the performance and reliability of the power module.

[0004] Therefore, it is urgent to design a new terminal structure to better adapt to the development needs of power modules and reduce the impact of the terminal structure on the performance of power modules. Utility Model Content

[0005] In view of the above problems, the purpose of the present invention is to provide a terminal structure and a power module for a power module, so as to change the lead-out path of the power module, improve its current distribution, reduce the stray inductance of various commutation circuits, and enhance the electrical performance and reliability of the power module.

[0006] According to one aspect of the present invention, a terminal structure for a power module is provided, comprising at least two stacked busbars, each busbar comprising: a main body having a first side and a second side facing each other; a connecting pin located on the first side of the main body, one end of the connecting pin being connected to the main body, and the other end of the connecting pin being electrically connected to a power unit of the power module; a lead-out portion located on the second side of the main body, the lead-out portion protruding from the second side of the main body; wherein the connecting pins comprise at least two groups, and the two groups of connecting pins are symmetrically arranged on the first side of the main body; the main bodies of different busbars are located in different planes, the connecting pins of different busbars are laterally staggered, and the lead-out portions of different busbars are laterally staggered.

[0007] Optionally, the other end of the connecting pin is connected through an insulating substrate or a conductive structure of the power module, thereby electrically connecting the connecting pin to the power unit.

[0008] Optionally, the lead-out portion of the busbar and the main body of the busbar are located in the same plane.

[0009] Optionally, at least part of the busbars includes two lead-out portions, and the two lead-out portions are symmetrically arranged on the second side of the main body.

[0010] Optionally, the connection pins of different busbars have different heights.

[0011] Optionally, each group of connecting pins includes at least two connecting pins, and each group of connecting pins has at least two connection points with the insulating substrate or the conductive structure of the power module.

[0012] Optionally, the main body further includes through holes, and the through holes on the main bodies of the stacked busbars are correspondingly provided.

[0013] Optionally, the insulating substrate of the power module includes a copper-clad ceramic substrate.

[0014] Optionally, the spacing between the main bodies of adjacent busbars is 0.5 mm to 4 mm.

[0015] Optionally, the spacing between the main bodies of adjacent busbars is 1 mm to 2.5 mm.

[0016] Optionally, the thickness of the main body is 0.3 mm to 2.5 mm.

[0017] Optionally, the thickness of the main body is 0.5 mm to 1.5 mm.

[0018] Optionally, it includes: a first busbar, a second busbar and a third busbar, and the main body of the first busbar is located between the main body of the second busbar and the main body of the third busbar.

[0019] Optionally, the connecting pins of the third busbar are located in the middle area of ​​one side of the insulating substrate or conductive structure of the power module; the two groups of connecting pins of the second busbar are located on both sides of the connecting pins of the third busbar; and the two groups of connecting pins of the first busbar are located on both sides of the connecting pins of the second busbar.

[0020] Optionally, the third busbar includes two lead-out parts located at both ends of the second side of the main body; the second busbar includes a lead-out part located in the middle area of ​​the second side of the main body; the first busbar includes two lead-out parts located on the second side of the main body, and the projection of the lead-out part of the first busbar in the direction perpendicular to the main body is located between the projection of the lead-out part of the second busbar and the projection of the lead-out part of the third busbar.

[0021] Optionally, in a direction perpendicular to the main body of the busbar, the projections of the connection pins of different busbars do not overlap, and the projections of the lead-out portions of different busbars do not overlap.

[0022] According to another aspect of the present invention, a power module is provided, comprising the above-mentioned terminal structure.

[0023] The terminal structure and power module provided by this utility model utilize double-terminal technology to electrically connect the power cells of the power module and utilize a laminated structure. For power modules with multiple power chips connected in parallel, this significantly reduces variations between parallel circuits, improves current distribution between power semiconductor chips, and enhances power module reliability. The laminated design significantly reduces stray inductance in the power module's main circuit, ensuring the power module's switching characteristics, reducing switching voltage oscillations and current waveform oscillations, and optimizing electrical performance and reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0025] Figure 1 Shows a schematic diagram of the packaging of the power module of the utility model;

[0026] Figure 2 Shows a top view of the first busbar in the terminal structure of the present invention;

[0027] Figure 3 A schematic diagram showing the connection between the first busbar and the insulating substrate of the power module in the terminal structure of the present invention is shown;

[0028] Figure 4 Shows a top view of the second busbar in the terminal structure of the present invention;

[0029] Figure 5 A schematic diagram showing the connection between the second busbar and the insulating substrate of the power module in the terminal structure of the present invention is shown;

[0030] Figure 6 Shows a top view of the third busbar in the terminal structure of the present invention;

[0031] Figure 7 A schematic diagram showing the connection between the third busbar and the insulating substrate of the power module in the terminal structure of the present invention is shown;

[0032] Figure 8 A side view showing the connection between the terminal structure of the present invention and the insulating substrate of the power module. DETAILED DESCRIPTION

[0033] The present invention will be described in more detail below with reference to the accompanying drawings. For the sake of clarity, parts in the drawings are not drawn to scale. In addition, certain well-known parts may not be shown. Numerous specific details of the present invention are described below, but as those skilled in the art will appreciate, the present invention may be practiced without these specific details.

[0034] The present invention may be embodied in various forms, some examples of which will be described below.

[0035] Figure 1 Shows a schematic diagram of the packaging of the power module of the utility model;

[0036] like Figure 1 The power module comprises a housing 1, a heat sink base plate 2, an insulating substrate 3 for the power module, a power chip 4, and a terminal structure connected to the insulating substrate 3 for connecting terminals. The power chip includes, but is not limited to, a silicon carbide metal oxide semiconductor field effect transistor (SiC MOSFET), an insulated gate field effect transistor (IGBT) chip, a freewheeling diode (FRD) chip, and the like. The insulating substrate 3 of the power module is, for example, a copper-clad ceramic substrate, although it can also be other conductive structures. The terminal structure is at least partially encapsulated in the housing 1 and includes, for example, a first busbar A, a second busbar B, and a third busbar C. The insulating substrate 3 of the power module includes multiple different connection areas connected through different busbars. The second busbar B has a lead portion located in the middle of one side of the housing. The first busbar A includes two lead portions, which are located on either side of the lead portion of the second busbar B. The third busbar C also includes two lead portions, which are located on either side of the lead portion of the second busbar B.

[0037] Figure 2 A top view of the first busbar in the terminal structure of the present invention is shown; the first busbar A includes a main body with a rectangular outline, and four connecting pins M1~M4 are arranged on the first side of the main body, wherein the connecting pins M1 and M2 are a group, and the connecting pins M3 and M4 are a group, the two connecting pins in each group are the same in size and shape, and the two groups of connecting pins are symmetrically arranged along the dotted line in the figure; the second side of the main body of the first busbar A (the side opposite to the first side) is provided with two lead-out parts 5a and 5b, the lead-out parts 5a and 5b protrude from the second side, and the lead-out parts 5a and 5b are located in the same plane as the main body of the first busbar A; the lead-out parts 5a and 5b have the same shape and size, for example, both are rectangular, and the short side of the rectangle is connected to the main body, and the lead-out parts 5a and 5b are symmetrically arranged along the dotted line in the figure.

[0038] Figure 3A schematic diagram of the connection between the first busbar and the insulating substrate of the power module in the terminal structure of the present invention is shown; the connecting pins M1~M4 all have a bent portion, which raises the main body of the first busbar A so that the main body of the first busbar A and the insulating substrate 3 of the power module are not in the same plane, the connecting pins M1 and M2 are connected to the same connection area at one end of the side of the insulating substrate 3 of the power module, and the connecting pins M3 and M4 are connected to the same connection area at the other end of the side plate of the insulating substrate 3 of the power module. The two end areas of the main body of the first busbar A also include a through hole E1 and a through hole E2 perpendicular to the main body plane, and the two through holes are also symmetrically arranged on the main body of the first busbar A.

[0039] Figure 4 A top view of the second busbar in the terminal structure of the present invention is shown; the second busbar B includes a main body with a rectangular outline, and four connecting pins N1 to N4 are provided on the first side of the main body, wherein the connecting pins N1 and N2 form a group, and the connecting pins N3 and N4 form a group, the two connecting pins in each group are identical in size and shape, and the two groups of connecting pins are symmetrically arranged along the dotted line in the figure; a lead portion 6 is provided in the middle area of ​​the second side (the side opposite to the first side) of the main body of the second busbar B, the lead portion 6 protrudes from the second side, and the lead portion 6 and the main body of the second busbar B are located in the same plane; the lead portion 6 is, for example, rectangular.

[0040] Figure 5 A schematic diagram of the connection between the second busbar and the insulating substrate of the power module in the terminal structure of the present invention is shown; the connecting pins N1~N4 all have a bent portion, which raises the main body of the second busbar B so that the main body of the second busbar B and the insulating substrate 3 of the power module are not in the same plane. The second busbar B is located above the first busbar A, for example; the connecting pins N1 and N2 are connected to the same connection area at one end of the side of the insulating substrate 3 of the power module, and the connecting pins N3 and N4 are connected to the same connection area at the other end of the side plate of the insulating substrate 3 of the power module. The two end areas of the main body of the second busbar B also include through holes F1 and through holes F2 perpendicular to the main body plane. The two through holes are also symmetrically arranged on the main body of the second busbar B.

[0041] Figure 6A top view of the third busbar in the terminal structure of the present invention is shown; the third busbar C includes a main body with a rectangular outline, and four connecting pins R1 to R4 are arranged on the first side of the main body, wherein the connecting pins R1 and R2 form a group, and the connecting pins R3 and R4 form a group, the two connecting pins in each group have the same size and shape, and the two groups of connecting pins are symmetrically arranged along the dotted line in the figure; the second side of the main body of the third busbar C (the side opposite to the first side) is provided with two lead-out parts 7a and 7b, the lead-out parts 7a and 7b protrude from the second side, and the lead-out parts 7a and 7b are located in the same plane as the main body of the third busbar C; the lead-out parts 7a and 7b have the same shape and size, for example, both are rectangular, and the short side of the rectangle is connected to the main body, and the lead-out parts 7a and 7b are symmetrically arranged along the dotted line in the figure.

[0042] Figure 7 A schematic diagram of the connection between the third busbar and the insulating substrate of the power module in the terminal structure of the present invention is shown; the connecting pins R1~R4 all have a bent portion, which raises the main body of the third busbar C so that the main body of the third busbar C and the insulating substrate 3 of the power module are not in the same plane. The main body of the third busbar C is located, for example, between the main body of the first busbar A and the main body of the second busbar B; the connecting pins R1~R4 are connected to the same connection area at one end of the side of the insulating substrate 3 of the power module, and the two end areas of the main body of the third busbar C also include a through hole G1 and a through hole G2 perpendicular to the plane of the main body. The two through holes are also symmetrically arranged on the main body of the third busbar C.

[0043] The through-holes of the first to third busbars are coaxial and of the same size, which can be used for positioning. Of course, the number of through-holes can be one or more. The lead-out portions of the busbars can be electrically connected by laser welding, screw connections, or other methods.

[0044] Figure 8 A side view shows the connection between the terminal structure of the present invention and the insulating substrate of a power module. The thickness of the main body of the first busbar A is H1, the thickness of the main body of the second busbar B is H2, and the thickness of the main body of the third busbar C is H3. The thickness of each of these busbar bodies is, for example, 0.3mm to 2.5mm, and preferably, the thickness of each busbar body is 0.5mm to 1.5mm. The distance between the main body of the second busbar B and the main body of the third busbar C is L1, and the distance between the main body of the first busbar A and the main body of the third busbar C is L2. The distance between adjacent busbar bodies is, for example, 0.5mm to 4mm, and preferably, the distance between adjacent busbar bodies is 1mm to 2.5mm.

[0045] Although the above embodiment only describes three busbars, and the main bodies of the three busbars are arranged at a specific height, the upper and lower arrangement order of the stacked busbars can be arbitrarily combined according to needs and actual conditions. Of course, the connecting pins and lead-out parts can also be adjusted according to needs.

[0046] The terminal structure and power module provided by this utility model utilize double-terminal technology to electrically connect the power cells of the power module and utilize a laminated structure. For power modules with multiple power chips connected in parallel, this significantly reduces variations between parallel circuits, improves current distribution between power semiconductor chips, and enhances power module reliability. The laminated design significantly reduces stray inductance in the power module's main circuit, ensuring the power module's switching characteristics, reducing switching voltage oscillations and current waveform oscillations, and optimizing electrical performance and reliability.

[0047] It should be noted that in the description of the present invention, it is necessary to understand that the orientations or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “inside”, “outside”, “horizontal” and “vertical” are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, rather than indicating or implying that the device or component referred to must have a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0048] In this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus comprising the element.

[0049] As described above, these embodiments do not describe all details in detail, nor do they limit the present invention to the specific embodiments described. Obviously, many modifications and variations are possible based on the above description. This specification selects and describes these embodiments in detail to better explain the principles and practical applications of the present invention, thereby enabling those skilled in the art to better utilize the present invention and its modifications. The present invention is limited only by the claims and their full scope and equivalents.

Claims

1. A terminal structure for a power module, characterized in that: The invention comprises at least two stacked busbars, each busbar comprising: a body having opposing first and second sides; a connecting pin, located on a first side of the main body, one end of the connecting pin being connected to the main body, and the other end of the connecting pin being electrically connected to a power unit of the power module; The lead-out portion is located at the second side of the main body, and the lead-out portion protrudes from the second side of the main body; Wherein, the connecting pins include at least two groups, and the two groups of connecting pins are symmetrically arranged on the first side of the main body; The main bodies of different busbars are located in different planes, the connection pins of different busbars are staggered laterally, and the lead-out parts of different busbars are staggered laterally.

2. The terminal structure according to claim 1, wherein: The other end of the connecting pin is connected through the insulating substrate or the conductive structure of the power module, thereby electrically connecting the connecting pin to the power unit.

3. The terminal structure according to claim 2, wherein: The lead-out portion of the busbar and the main body of the busbar are located in the same plane.

4. The terminal structure according to claim 1, wherein: At least part of the busbar includes two lead-out portions, and the two lead-out portions are symmetrically arranged on the second side of the main body.

5. The terminal structure according to claim 1, wherein: The heights of the connection pins of different busbars are different.

6. The terminal structure according to claim 2, wherein: Each group of connecting pins includes at least two connecting pins connected to the insulating substrate or the conductive structure, and each group of connecting pins has at least two connection points with the insulating substrate or the conductive structure of the power module.

7. The terminal structure according to claim 1, wherein: The main body further includes through holes, and the through holes on the main bodies of the stacked busbars are correspondingly arranged.

8. The terminal structure according to claim 2, wherein: The insulating substrate of the power module includes a copper-clad ceramic substrate.

9. The terminal structure according to claim 1, wherein: The spacing between the bodies of adjacent busbars is 0.5mm~4mm.

10. The terminal structure according to claim 1, wherein: The spacing between the bodies of adjacent busbars is 1mm~2.5mm.

11. The terminal structure according to claim 1, wherein: The thickness of the main body is 0.3mm~2.5mm.

12. The terminal structure according to claim 1, wherein: The thickness of the main body is 0.5mm~1.5mm.

13. The terminal structure according to claim 2, wherein: include: A first busbar, a second busbar and a third busbar, wherein the main body of the first busbar is located between the main bodies of the second busbar and the third busbar.

14. The terminal structure according to claim 13, characterized in that: The connection pin of the third busbar is located in the middle area of ​​one side of the insulating substrate or the conductive structure of the power module; The two groups of connection pins of the second busbar are located on both sides of the connection pins of the third busbar; The two groups of connection pins of the first busbar are located on both sides of the connection pins of the second busbar.

15. The terminal structure according to claim 14, characterized in that: The third busbar includes two lead-out portions located at both ends of the second side of the main body; The second busbar includes a lead-out portion located in the middle area of ​​the second side of the main body; The first busbar includes two lead-out portions located on the second side of the main body, and the projection of the lead-out portion of the first busbar in a direction perpendicular to the main body is located between the projection of the lead-out portion of the second busbar and the projection of the lead-out portion of the third busbar.

16. The terminal structure according to claim 1, wherein: In a direction perpendicular to the main body of the busbar, the projections of the connection pins of different busbars do not overlap, and the projections of the lead-out portions of different busbars do not overlap.

17. A power module, characterized in that: Comprising the terminal structure according to any one of claims 1 to 16.

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