Power module

Abstract

The invention relates to a power module, and relates to the technical field of electronic devices. The power module includes: a substrate; at least part of the metal terminal is positioned on one side of the lining plate; a plurality of groups of bridge arms, each group of bridge arms being arranged at intervals along a first direction, each group of bridge arms comprising a plurality of power chips arranged at intervals along a second direction, each power chip being located at one side of the lining plate; and a plurality of first binding wires, any two adjacent power chips in the same group of bridge arms are electrically connected through at least one first binding wire, and the head power chip and the tail power chip are electrically connected with the metal terminal through at least one first binding wire respectively. The power module provided by the invention has the advantages of small thermal resistance, small thermal loss and small stray inductance.

Description

Technical Field

[0001] The present application relates to the technical field of electronic devices, and in particular to a power module. Background Art

[0002] With the development of vehicle technology, vehicle range is one of the important issues that the industry is concerned about. The main factors affecting the range include power conversion efficiency, and the electronic device that is closely related to power conversion efficiency is the power module.

[0003] However, a single-piece copper clip is generally used for interconnection inside the power module, and this interconnection method results in a large thermal resistance of the power module. Summary of the invention

[0004] Based on this, it is necessary to provide a power module with smaller thermal resistance to reduce the heat loss and stray inductance of the power module.

[0005] In a first aspect, an embodiment of the present application provides a power module, including:

[0006] Liner board;

[0007] a metal terminal, at least a portion of which is located on one side of the liner;

[0008] A plurality of groups of bridge arms, each group of bridge arms is arranged at intervals along a first direction, each group of bridge arms comprises a plurality of power chips arranged at intervals along a second direction, and each of the power chips is located on one side of the liner;

[0009] A plurality of first binding wires, wherein in the same group of the bridge arms, any two adjacent power chips are electrically connected via at least one first binding wire, and the first and last two power chips are electrically connected to the metal terminal via at least one first binding wire respectively.

[0010] In one embodiment, the liner includes an insulating layer and a copper-clad layer located on one side of the insulating layer, and the copper-clad layer includes a first copper-clad layer, a second copper-clad layer, a third copper-clad layer and a fourth copper-clad layer that are arranged at intervals;

[0011] The metal terminal at least includes a power terminal, and the power terminal includes an AC terminal, a negative DC terminal and a positive DC terminal; wherein the AC terminal is electrically connected to the first copper cladding layer, the negative terminal is electrically connected to the third copper cladding layer, and the positive DC terminal is electrically connected to the fourth copper cladding layer.

[0012] In one embodiment, the first copper clad layer is close to the first side of the lining board, the third copper clad layer is close to the second side of the lining board, the fourth copper clad layer is close to the second side, the third side and the fourth side of the lining board respectively, and the second copper clad layer is located in the area surrounded by the second copper clad layer and the third copper clad layer; wherein the first side and the second side are two sides arranged opposite to each other in the second direction, and the third side and the fourth side are two sides arranged opposite to each other in the first direction.

[0013] In one embodiment, the bridge arm includes at least one upper bridge power chip and at least one lower bridge power chip spaced apart along the second direction, the first surface of each upper bridge power chip contacts and is electrically connected to the fourth copper clad layer, and the first surface of each lower bridge power chip contacts and is electrically connected to the second copper clad layer; wherein,

[0014] In each group of the bridge arms, in the second direction, the second surface of the upper bridge power chip close to the first copper clad layer is electrically connected to the first copper clad layer through at least one binding wire, the second surface of the upper bridge power chip close to the second copper clad layer is electrically connected to the second copper clad layer through at least one first binding wire, and the second surface of the lower bridge power chip close to the third copper clad layer is electrically connected to the third copper clad layer through at least one first binding wire.

[0015] In one embodiment, the copper clad layer further includes a fifth copper clad layer, a sixth copper clad layer and a seventh copper clad layer which are arranged at intervals; the metal terminal further includes a signal terminal located on the first side of the liner, and the signal terminal at least includes a lower bridge source terminal, an upper bridge drain terminal, an upper bridge gate terminal, an upper bridge source terminal and a lower bridge gate terminal; wherein,

[0016] The lower bridge source terminal is electrically connected to the fifth copper clad layer, the upper bridge gate terminal is electrically connected to the sixth copper clad layer, the upper bridge drain terminal is electrically connected to the fourth copper clad layer, the upper bridge source terminal is electrically connected to the first copper clad layer, and the lower bridge gate terminal is electrically connected to the seventh copper clad layer.

[0017] In one embodiment, the fifth copper clad layer is close to the third edge of the lining board and adjacent to the fourth copper clad layer, a portion of the sixth copper clad layer is located in the gap between the first copper clad layer and the fourth copper clad layer, and the seventh copper clad layer is close to the fourth edge and adjacent to the fourth copper clad layer; wherein the fifth copper clad layer and the seventh copper clad layer are symmetrically arranged along the second direction.

[0018] In one embodiment, the bridge arm includes at least one upper bridge power chip and at least one lower bridge power chip arranged at intervals along the second direction; wherein,

[0019] The power module also includes multiple second binding wires, the fifth copper clad layer is electrically connected to the third copper clad layer through at least one of the second binding wires, the gate of each of the upper bridge power chips is electrically connected to the sixth copper clad layer through at least one of the second binding wires, and the gate of each of the lower bridge power chips is electrically connected to the seventh copper clad layer through at least one of the second binding wires.

[0020] In one embodiment, the power module further includes at least one upper bridge gate resistor and at least one lower bridge gate resistor; wherein,

[0021] The upper bridge gate resistor is located between a plurality of adjacent upper bridge power chips, a first end of the upper bridge gate resistor is electrically connected to the gates of the plurality of adjacent upper bridge power chips through a plurality of the second binding wires, and a second end of the upper bridge gate resistor is electrically connected to the sixth copper clad layer through at least one of the second binding wires;

[0022] The lower bridge gate resistor is located between multiple adjacent lower bridge power chips, the first end of the lower bridge gate resistor is electrically connected to the gates of the multiple adjacent lower bridge power chips through multiple second binding wires, and the second end of the lower bridge gate resistor is electrically connected to the seventh copper cladding layer through at least one second binding wire.

[0023] In one of the embodiments, the power module further comprises:

[0024] A first pre-coated silver layer is located between the power chip and the liner;

[0025] A second pre-coated silver layer is located on a side of the power chip away from the first pre-coated silver layer;

[0026] The copper foil layer is located on a side of the second pre-coated silver layer away from the power chip; wherein part of the first binding wires are respectively connected to the copper foil layer and the liner, so that part of the port of the power chip is electrically connected to the metal terminal.

[0027] In one embodiment, the power module further includes a heat dissipation base plate, which includes a heat dissipation substrate and a plurality of diamond-shaped heat dissipation pin fins. The heat dissipation substrate is located on a side of the liner away from the power chip, and each of the diamond-shaped heat dissipation pin fins is located on a side of the heat dissipation substrate close to the liner.

[0028] The above-mentioned power module includes a backing plate, a metal terminal, multiple groups of bridge arms and multiple first binding wires, wherein at least part of the metal terminal is located on one side of the backing plate, each group of bridge arms is arranged at intervals along the first direction, each group of bridge arms includes multiple power chips arranged at intervals along the second direction, each power chip is located on one side of the backing plate, and in the same group of bridge arms, any two adjacent power chips are electrically connected by at least one first binding wire, and the first and last power chips in the second direction are respectively electrically connected to the metal terminal by at least one first binding wire. Since the electrical connection between the power chips or between the power chips and the metal terminals is achieved by using mutually independent first binding wires, compared with the one-piece copper sheet used in the prior art, the first binding wire is short in length and narrow in width. Therefore, the power module provided by the present application has smaller thermal resistance, smaller heat loss, smaller stray inductance, and better performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 An exploded schematic diagram of a power module provided in an embodiment of the present application;

[0031] Figure 2 A schematic diagram of the structure of a power module provided in an embodiment of the present application;

[0032] Figure 3 A schematic top view of a power module provided in an embodiment of the present application;

[0033] Figure 4 A schematic diagram of the structure of some components of a power module provided in an embodiment of the present application;

[0034] Figure 5 A schematic top view of a partial structure of a power module provided in an embodiment of the present application;

[0035] Figure 6 A schematic diagram of a packaging structure of a power module provided in an embodiment of the present application;

[0036] Figure 7 A schematic top view of a power module packaged according to an embodiment of the present application;

[0037] Figure 8 A schematic side view of a power module packaged according to an embodiment of the present application;

[0038] Fig. 9A schematic top view of another power module packaged according to an embodiment of the present application.

[0039] Description of reference numerals:

[0040] 10- lining board, 11- copper clad layer, 111- first copper clad layer, 112- second copper clad layer, 113- third copper clad layer, 114- fourth copper clad layer, 115- fifth copper clad layer, 116- sixth copper clad layer, 117- seventh copper clad layer, 118- eighth copper clad layer, 12- insulation layer, 13- copper layer, 14- solder layer, 20- metal terminal, 21- power terminal, 211- AC terminal, 222- negative DC terminal, 22 3-positive DC terminal, 22-signal terminal, 221-lower bridge source terminal, 222-upper bridge drain terminal, 223-upper bridge gate terminal, 224-upper bridge source terminal, 225-lower bridge gate terminal, 226-temperature detection terminal, 30-power chip, 41-first binding wire, 42-second binding wire, 50-gate resistor, 60-heat dissipation base plate, 61-heat dissipation substrate, 62-diamond heat dissipation pin fins, 70-plastic package shell. DETAILED DESCRIPTION

[0041] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0043] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first binding line may be referred to as a second binding line, and similarly, a second binding line may be referred to as a first binding line. Both the first binding line and the second binding line are binding lines, but they are not the same binding line.

[0044] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0045] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least a portion of an element” means a part or all of an element.

[0046] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0047] Figure 1 An exploded schematic diagram of a power module provided in an embodiment of the present application, Figure 2 A schematic diagram of the structure of a power module provided in an embodiment of the present application is shown in FIG. Figure 3 A schematic top view of a power module provided in an embodiment of the present application is shown in FIG. Figure 4 A schematic diagram of the structure of some components of a power module provided in an embodiment of the present application, Figure 5 A schematic top view of a partial structure of a power module provided in an embodiment of the present application, Figure 6 A schematic diagram of a packaging structure of a power module provided in an embodiment of the present application, Figure 7 A schematic top view of a power module packaged according to an embodiment of the present application is shown in FIG. Figure 8 A schematic side view of a power module packaged according to an embodiment of the present application is shown in FIG. Fig. 9 This is a top view schematic diagram of another power module packaged according to an embodiment of the present application. Figures 1 to 9 , the power module provided in this application is introduced.

[0048] In one embodiment, a power module is provided, comprising: a backing plate 10, a metal terminal 20, a plurality of bridge arms, and a plurality of first binding wires 41. At least a portion of the metal terminal 20 is located on one side of the backing plate 10. The remaining portion of the metal terminal 20 may extend outward in a direction away from the backing plate 10. The orthographic projection of the metal terminal 20 on the backing plate 10 partially overlaps with the backing plate 10. The metal terminal 20 may be in electrical connection with the backing plate 10 by contacting the backing plate 10.

[0049] Each group of bridge arms is arranged at intervals along the first direction. Each group of bridge arms includes a plurality of power chips 30 arranged at intervals along the second direction. Exemplarily, the power chip 30 may include a silicon carbide (SiC) power chip 30, an IGBT (Insulated Gate Bipolar Transistor) power chip 30, a Si-based power chip 30 or other types of chips. Among them, the first direction may be the X-axis direction, and the second direction may be the opposite direction of the Y-axis. Each power chip 30 is located on one side of the liner 10. The present application does not specifically limit the number of power chips 30 included in the power module, which may be 8, 12, 16 or other suitable values, and may actually be set accordingly according to the scene requirements.

[0050] In the same group of bridge arms, any two adjacent power chips 30 are electrically connected through at least one first binding wire 41, and the first and last power chips 30 in the second direction are electrically connected to the metal terminal 20 through at least one first binding wire 41. The power chips 30 can be electrically connected to the liner 10 through the first binding wire 41, so as to achieve electrical connection with the metal terminal 20 through the liner 10. Exemplarily, the power chip 30 can be fixed on the liner 10 by welding or silver sintering. The material of the solder layer 14 between the power chip 30 and the liner 10 can be tin-antimony lead-free and halogen-free solder paste (SnSb). The first binding wire 41 used to electrically connect two adjacent power chips 30 is independent of the first binding wire 41 used to electrically connect the power chip 30 and the liner 10. Exemplarily, the material of the first binding wire 41 may include copper, aluminum or other metal materials.

[0051] The above-mentioned power module includes a liner 10, a metal terminal 20, multiple groups of bridge arms and multiple first binding wires 41, wherein at least part of the metal terminal 20 is located on one side of the liner 10, each group of bridge arms is arranged at intervals along the first direction, each group of bridge arms includes multiple power chips 30 arranged at intervals along the second direction, each power chip 30 is located on one side of the liner 10, and in the same group of bridge arms, any two adjacent power chips 30 are electrically connected by at least one first binding wire 41, and the first and last power chips 30 in the second direction are respectively electrically connected to the metal terminal 20 by at least one first binding wire 41. Since the electrical connection between the power chips 30 or between the power chip 30 and the metal terminal 20 is achieved by using mutually independent first binding wires 41, compared with the one-piece copper sheet used in the prior art, the first binding wire 41 is short in length and narrow in width. Therefore, the power module provided by the present application has smaller thermal resistance, smaller heat loss, smaller stray inductance, and better performance.

[0052] In one embodiment, the liner 10 includes an insulating layer 12 and a copper clad layer 11 located on one side of the insulating layer 12. Exemplarily, the liner 10 also includes a copper layer and a solder layer 14 located on the insulating layer 12 and away from the copper clad layer 11. The material of the insulating layer 12 may include ceramic, aluminum oxide, silicon nitride or other insulating materials. The material of the copper clad layer 11 may include copper. The copper clad layer 11 includes a first copper clad layer 111, a second copper clad layer 112, a third copper clad layer 113 and a fourth copper clad layer 114 arranged at intervals.

[0053] Exemplarily, the first copper clad layer 111 is close to the first side of the liner 10. The third copper clad layer 113 is close to the second side of the liner 10. The fourth copper clad layer 114 is close to the second side, the third side and the fourth side of the liner 10 respectively. The second copper clad layer 112 is located in the area surrounded by the second copper clad layer 112 and the third copper clad layer 113. The first side and the second side are two sides arranged opposite to each other in the second direction, and the third side and the fourth side are two sides arranged opposite to each other in the first direction. For example, Figure 3 In the embodiment, the first side of the liner 10 is the upper side, the second side of the liner 10 is the lower side, the third side of the liner 10 is the left side, and the fourth side of the liner 10 is the right side. Exemplarily, the first copper clad layer 111 and the second copper clad layer 112 are rectangular structures, the third copper clad layer 113 is a convex structure, and the fourth copper clad layer 114 is a concave structure. The first copper clad layer 111, the second copper clad layer 112, the third copper clad layer 113 and the fourth copper clad layer 114 are arranged in sequence in the second direction, and the first copper clad layer 111, the second copper clad layer 112, the third copper clad layer 113 and the fourth copper clad layer 114 are symmetrical along the second direction. Exemplarily, the area of ​​the first copper clad layer 111 is respectively greater than the area of ​​the second copper clad layer 112, the area of ​​the third copper clad layer 113 and the area of ​​the fourth copper clad layer 114. In this way, by redesigning the layout of the liner 10, the liner 10 has a higher symmetry, so that the power module has better current sharing consistency.

[0054] Exemplarily, the metal terminal 20 includes at least a power terminal 21. The power terminal 21 includes an AC terminal 211, a negative DC terminal 212, and a positive DC terminal 213. Exemplarily, the power terminal 21 may include an AC terminal 211, a negative DC terminal 212, and two positive DC terminals 213. The AC terminal 211 is located on the first side of the liner 10, the negative DC terminal 212 and the two positive DC terminals 213 are respectively located on the second side of the liner 10 and are arranged in sequence along the first direction, and the two positive DC terminals 213 are respectively located on both sides of the negative DC terminal 212.

[0055] Among them, the AC terminal 211 is electrically connected to the first copper clad layer 111. At least part of the AC terminal 211 is located on the side of the first copper clad layer 111 away from the insulating layer 12. The remaining part of the AC terminal 211 extends outward in a direction away from the first side of the liner 10. The negative terminal is electrically connected to the third copper clad layer 113. At least part of the negative DC terminal 212 is located on the side of the third copper clad layer 113 away from the insulating layer 12. The remaining part of the negative DC terminal extends outward in a direction away from the second side of the liner 10. The positive DC terminal 213 is electrically connected to the fourth copper clad layer 114. At least part of the positive DC terminal 213 is located on the side of the fourth copper clad layer 114 away from the insulating layer 12. The remaining part of the positive DC terminal 213 extends outward in a direction away from the second side of the liner 10.

[0056] The above-mentioned power module adopts the design of laminated terminals to construct a loop with opposite current directions, so that the loop forms magnetic fluxes that cancel each other out, reduces the stray inductance of the loop, reduces crosstalk and electromagnetic interference (EMI), improves signal transmission performance, saves costs, and facilitates layout. Specifically, an AC terminal 211, a negative DC terminal 212 and two positive DC terminals 213 are used to form the overall power loop. The power switching loop is set into two symmetrical parts through the design of three DC terminals, which can effectively reduce the inductance of the loop by two times. In terms of the layout of the liner 10, while considering its high symmetry, two positive DC terminals 213 are used to flow current when designing the first copper cladding layer 111. The liner 10 is designed to flow in a large area, which effectively increases the maximum current carrying capacity of the module.

[0057] In one embodiment, the bridge arm includes at least one upper bridge power chip 30 and at least one lower bridge power chip 30 arranged at intervals along the second direction. Exemplarily, the number of upper bridge power chips 30 and lower bridge power chips 30 in each group of bridge arms is the same. The number of upper bridge power chips 30 and lower bridge power chips 30 in each group of bridge arms can be 1, 2 or other suitable values, respectively, which are not limited here. For example, in Figure 3 In the embodiment, each group of bridge arms includes two upper bridge power chips 30 and two lower bridge power chips 30 which are sequentially arranged at intervals along the Y-axis direction.

[0058] The first surface of each upper bridge power chip 30 contacts and is electrically connected to the fourth copper clad layer 114, and the first surface of each lower bridge power chip 30 contacts and is electrically connected to the second copper clad layer 112. In each group of bridge arms, in the second direction, the second surface of the upper bridge power chip 30 close to the first copper clad layer 111 is electrically connected to the first copper clad layer 111 through at least one bonding wire, the second surface of the upper bridge power chip 30 close to the second copper clad layer 112 is electrically connected to the second copper clad layer 112 through at least one first bonding wire 41, and the second surface of the lower bridge power chip 30 close to the third copper clad layer 113 is electrically connected to the third copper clad layer 113 through at least one first bonding wire 41.

[0059] For example, in Figure 3 In the embodiment, the first surface is the lower surface and the second surface is the upper surface; in each group of bridge arms, along the Y-axis direction, the upper surface of the upper bridge power chip 30 close to the first copper layer, that is, the upper surface of the first upper bridge power chip 30, is electrically connected to the first copper clad layer 111 through two first binding wires 41, thereby realizing electrical connection with the AC terminal 211. The upper surfaces of the first and second upper bridge power chips 30 are electrically connected through two first binding wires 41, thereby realizing the series connection between multiple upper bridge power chips 30 in the same group of bridge arms. The second surface of the upper bridge power chip 30 close to the second copper clad layer 112, that is, the second upper bridge power chip 30, is electrically connected to the second copper clad layer 112 through two first binding wires 41, thereby realizing the series connection between the upper bridge power chip 30 and the lower bridge power chip 30 in the same group of bridge arms. The upper surfaces of the first and second lower bridge power chips 30 are electrically connected through two first binding wires 41, thereby realizing the series connection between multiple lower bridge power chips 30 in the same group of bridge arms. The second surface of the lower bridge power chip 30 close to the third copper clad layer 113 , ie, the second lower bridge power chip 30 , is electrically connected to the third copper clad layer 113 through two first binding wires 41 , thereby being electrically connected to the negative DC terminal 212 .

[0060] The above-mentioned power module uses multiple independent first binding wires 41 to achieve electrical connection between the two upper bridge power chips 30 in the same group of bridge arms, between the upper bridge power chip 30 and the AC terminal 211, between the upper bridge power chip 30 and the lower bridge power chip 30, between the two lower bridge power chips 30, and between the lower bridge power chip 30 and the negative DC terminal 212. Since the power chips 30 are arranged in an array and the distance between each structure is short, the length of the first binding wire 41 is small and the thermal resistance is small. Therefore, the heat loss of the power module is small and the stray inductance is small.

[0061] In one embodiment, the copper clad layer 11 further includes a fifth copper clad layer 115, a sixth copper clad layer 116, and a seventh copper clad layer 117 that are spaced apart. Exemplarily, the fifth copper clad layer 115 is close to the third side of the liner 10 and is adjacent to the fourth copper clad layer 114. Part of the sixth copper clad layer 116 is located in the gap between the first copper clad layer 111 and the fourth copper clad layer 114, and the seventh copper clad layer 117 is close to the fourth side and is adjacent to the fourth copper clad layer 114. Exemplarily, the fifth copper clad layer 115 and the seventh copper clad layer 117 are symmetrically arranged along the second direction. Exemplarily, the size of the fifth copper clad layer 115 in the second direction is greater than the size in the first direction. For example, in Figure 2 and Figure 3 In the embodiment, the fifth copper-clad layer 115 has a longitudinally elongated structure. The size of the sixth copper-clad layer 116 in the first direction is greater than that in the second direction. Figure 2 and Figure 3 In the embodiment, the sixth copper-clad layer 116 has a laterally elongated structure. The size of the seventh copper-clad layer 117 in the second direction is greater than that in the first direction. Figure 2 and Figure 3 In the embodiment, the seventh copper cladding layer 117 has a longitudinally elongated structure.

[0062] The metal terminal 20 also includes a signal terminal 22 located at the first side of the substrate 10. The signal terminal 22 at least includes a lower bridge source terminal 221, an upper bridge drain terminal 222, an upper bridge gate terminal 223, an upper bridge source terminal 224 and a lower bridge gate terminal 225 arranged in sequence along the first direction, and these signal terminals 22 are respectively located on both sides of the AC terminal 211. For example, Figure 2 and Figure 3 In the figure, the lower bridge source terminal 221, the upper bridge drain terminal 222, and the upper bridge gate terminal 223 are located on the left side of the AC terminal 211, and the remaining signal terminals 22 are located on the right side of the AC terminal 211. The lower bridge source terminal 221 is electrically connected to the fifth copper clad layer 115, the upper bridge gate terminal 223 is electrically connected to the sixth copper clad layer 116, the upper bridge drain terminal 222 is electrically connected to the fourth copper clad layer 114, the upper bridge source terminal 224 is electrically connected to the first copper clad layer 111, and the lower bridge gate terminal 225 is electrically connected to the seventh copper clad layer 117.

[0063] The above-mentioned power module adopts multiple signal terminals 22 to realize drive circuit control, and considering that the longer bonding distance places very stringent requirements on the process of the module and is prone to failure, the present application designs a longitudinally slender fifth copper clad layer 115 and a seventh copper clad layer 117 on the left and right sides of the liner 10, respectively, and designs a transversely slender sixth copper clad layer 116 near the AC terminal 211 for transition. This reduces the length of the bonding wire, effectively reduces the difficulty of the binding wire in the processing technology, improves the reliability of the module while also ensuring the current sharing capability of the module.

[0064] In one embodiment, the power module further includes a plurality of second binding wires 42. Exemplarily, the material of the second binding wires 42 may include copper, aluminum or other metal materials. The fifth copper clad layer 115 is electrically connected to the third copper clad layer 113 through at least one second binding wire 42, thereby realizing an electrical connection between the lower bridge source terminal 221 and the third copper clad layer 113. Based on the above, it can be seen that the second surface of the lower bridge power chip 30 is electrically connected to the third copper clad layer 113, thereby realizing an electrical connection between the lower bridge source terminal 221 and the second surface of the lower bridge power chip 30. The gate of each upper bridge power chip 30 is electrically connected to the sixth copper clad layer 116 through at least one second binding wire 42. Based on the above, it can be seen that the sixth copper clad layer 116 is electrically connected to the upper bridge gate terminal 223, thereby realizing an electrical connection between the gate of the upper bridge power chip 30 and the upper bridge gate terminal 223. The gate of each lower bridge power chip 30 is electrically connected to the seventh copper cladding layer 117 through at least one second binding wire 42. Based on the above, it can be known that the seventh copper cladding layer 117 is electrically connected to the lower bridge gate terminal 225, thereby realizing the electrical connection between the gate of the lower bridge power chip 30 and the lower bridge gate terminal 225.

[0065] In one embodiment, the signal terminal 22 may further include at least one temperature detection terminal 226. The temperature detection terminal 226 is located at the first side of the backing plate 10. For example, Figure 2 and Figure 3 In the embodiment, the power module includes two temperature detection terminals 226, which are respectively located between the upper bridge source terminal 224 and the lower bridge gate terminal 225. The power module also includes a temperature sensor, which is electrically connected to the two temperature detection terminals 226 through the second binding wire 42, so as to detect the temperature of the power module and improve the reliability and safety of the power module.

[0066] In one embodiment, the copper clad layer 11 may further include an eighth copper clad layer 118, wherein a portion of the upper bridge drain terminal 222 is located on a side of the eighth copper clad layer 118 away from the insulating layer 12 to be electrically connected to the eighth copper clad layer 118, and the eighth copper clad layer 118 is electrically connected to the fourth copper clad layer 114 through the second binding wire 42, thereby realizing electrical connection between the upper bridge drain terminal 222 and the first surface of the upper bridge power chip 30. Exemplarily, at least one of the fourth copper clad layer 114 and the eighth copper clad layer 118 has a groove structure, and the influence of large current on the input of the signal terminal 22 can be effectively avoided by opening the groove.

[0067] In one embodiment, the power module further includes at least one upper bridge gate resistor 50 and at least one lower bridge gate resistor 50. Exemplarily, the number of the upper bridge gate resistor 50 and the number of the lower bridge gate resistor 50 are the same. For example, the number of the upper bridge gate resistor 50 and the number of the lower bridge gate resistor 50 can be 1, 2 or other suitable values, respectively, which are not limited here. Figure 2 and Figure 3 In the embodiment, there are two upper bridge gate resistors 50 and two lower bridge gate resistors 50 .

[0068] The upper bridge gate resistor 50 is located between a plurality of adjacent upper bridge power chips 30, a first end of the upper bridge gate resistor 50 is electrically connected to the gates of a plurality of adjacent upper bridge power chips 30 through a plurality of second binding wires 42, and a second end of the upper bridge gate resistor 50 is electrically connected to the sixth copper clad layer 116 through at least one second binding wire 42. For example, Figure 2 and Figure 3 In the figure, each upper bridge gate resistor 50 is located between four upper bridge power chips 30 in two adjacent groups of bridge arms, and the first end of each upper bridge gate resistor 50 is electrically connected to the gates of the four adjacent upper bridge power chips 30 through four second binding wires 42, and the second end of each upper bridge gate resistor 50 is electrically connected to the sixth copper cladding layer 116 through a second binding wire 42, thereby realizing the electrical connection between the gate of each upper bridge power chip 30 and the upper bridge gate terminal 223 through the upper bridge gate resistor 50.

[0069] The lower bridge gate resistor 50 is located between a plurality of adjacent lower bridge power chips 30, a first end of the lower bridge gate resistor 50 is electrically connected to the gates of a plurality of adjacent lower bridge power chips 30 through a plurality of second binding wires 42, and a second end of the lower bridge gate resistor 50 is electrically connected to the seventh copper clad layer 117 through at least one second binding wire 42. For example, in Figure 2 and Figure 3 In the figure, each lower bridge gate resistor 50 is located between four lower bridge power chips 30 in two adjacent groups of bridge arms, and the first end of each lower bridge gate resistor 50 is electrically connected to the gates of the four adjacent lower bridge power chips 30 through four second binding wires 42, and the second end of each lower bridge gate resistor 50 is electrically connected to the seventh copper cladding layer 117 through a second binding wire 42, thereby realizing the electrical connection between the gate of each lower bridge power chip 30 and the lower bridge gate terminal 225 through the lower bridge gate resistor 50.

[0070] In the above power module structure design process, multiple gate resistors 50 are added, and the gate of the power chip 30 is interconnected with the gate terminal through the gate resistor 50 through the second binding wire 42, thereby reducing the impact of gate oscillation on the performance of the power module and improving the reliability of the power module.

[0071] In one embodiment, the power module further includes a first pre-coated silver layer, a second pre-coated silver layer and a copper foil layer. The first pre-coated silver layer is located between the power chip 30 and the backing plate 10. The second pre-coated silver layer is located on the side of the power chip 30 away from the first pre-coated silver layer. The copper foil layer is located on the side of the second pre-coated silver layer away from the power chip 30. The material of the pre-coated silver layer includes a silver sintering agent. Part of the first binding wire 41 is respectively connected to the copper foil layer and the backing plate 10 so that part of the port of the power chip 30 is electrically connected to the metal terminal 20. In the application, during the interconnection process, the power module provided by the embodiment of the present application can adopt the DTS (DieTop System) technology, and the first binding wire 41 can use copper wire instead of aluminum wire, and by pre-coating a silver layer on the copper sheet, the power chip 30 is protected from the damage caused by the high bonding force of the copper wire bonding. At the same time, it can also evenly distribute the heat generated by the current passing through the chip, which can effectively reduce the local temperature peak of the chip. In the bonding process, the thermal compression bonding process can be used to replace the traditional reflow soldering, which effectively improves the overall electrothermal performance of the module. In addition, the use of silver sintering agent instead of solder, DTS sintering and copper wire instead of the top aluminum wire, under extreme conditions, the life span is increased by at least 10 times.

[0072] In one embodiment, the power module further includes a heat dissipation base plate 60, which includes a heat dissipation substrate 61 and a plurality of diamond-shaped heat dissipation pin fins 62 (pinfins), the heat dissipation substrate 61 is located on the side of the liner 10 away from the power chip 30, and each diamond-shaped heat dissipation pin fin 62 is located on the side of the heat dissipation substrate 61 close to the liner 10. Compared with traditional circular or elliptical heat dissipation pin fins, the power module provided in the embodiment of the present application adopts a diamond-shaped heat dissipation pin fin 62 structure, which can effectively reduce water resistance and backflow phenomenon while keeping the overall heat dissipation area unchanged, and at the same time can enhance the heat dissipation effect of the module, and the overall heat dissipation effect is improved by about 20%.

[0073] In one embodiment, the power module also includes a cooler and a plastic shell 70, wherein the cooler can be made of copper, aluminum or other metals or alloys, the shell of the plastic shell 70 can be made of materials such as epoxy resin, and the potting material of the plastic shell 70 can be made of epoxy resin, silicone gel and other materials.

[0074] by Figure 2 and Figure 3For example, each power chip 30 in the power module is fixed on the backing plate 10 by welding or silver sintering, and one end of the first binding wire 41, i.e., the copper wire, is welded to the chip and the other end is welded to the backing plate 10 to realize the circuit connection of the upper and lower bridge arm chips; then the lead frame of the power terminal 21 and the signal terminal 22 is welded to the backing plate 10, and then the module is integrally sealed, and the sealed module is welded to the heat dissipation base plate 60 with diamond-shaped heat dissipation pin fins 62, and the lead frame in the plastic-sealed and cured module is cut to obtain the required power terminal 21 and signal terminal 22. The upper and lower half-area chips are arranged symmetrically, with a total of 16 silicon carbide chips; the upper and lower half-areas are separated and arranged by the trench of the backing plate 10, and the circuit is connected by the binding wire when the module is working; the upper and lower half-areas of the module are controlled to work alternately through the upper bridge gate terminal 223 and the lower bridge gate terminal 225.

[0075] When the power module is working, the upper and lower half bridges work in turn to realize the operation of the drive motor, and the gate signal terminal 22 is controlled by the driving signal to determine the half bridge working half bridge area. The upper half bridge chip is arranged symmetrically to reduce the parasitic inductance when the module is working. The chip is connected by the bonding method of DTS technology and TCB. When the upper bridge of the module is working, the current flows into the current from the two positive DC terminals 213, and flows into the power chip 30 through the fourth copper clad layer 114 of the liner 10. Then the copper binding wire is retained to the first copper clad layer 111 of the liner 10, enters the AC terminal 211, and completes the working circuit of the upper bridge. When the lower bridge of the power module is working, the current flows in from the AC terminal 211, passes through the first copper clad layer 111 of the liner 10, flows to the second copper clad layer 112 of the liner 10 through the three copper binding wires on the upper surface of the power chip 30, and then flows in from the bottom drain of the power chip 30, flows out to the top to the binding wire, returns to the third copper clad layer 113 of the liner 10, and finally remains at the negative DC terminal 212.

[0076] The power module provided by the present application adopts a laminated design to effectively reduce stray inductance, and has a high degree of symmetry and good current consistency by redesigning the layout of the chip and the liner 10. At the same time, a diamond pinfin heat dissipation design is adopted, and the heat dissipation effect is improved by 20% compared with the elliptical structure. The reasonable layout of the internal liner 10 is compatible with IGBT / SiC chips and has good compatibility. In addition, copper wire bonding is adopted in bonding, DTS technology is used for connection, and a combination of copper foil with pre-coated silver paste is adopted, which can effectively dissipate chip heat and improve the life and reliability of the module.

[0077] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0078] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0079] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A power module, characterized in that: include: Liner board; a metal terminal, at least a portion of which is located on one side of the liner; A plurality of groups of bridge arms, each group of bridge arms is arranged at intervals along a first direction, each group of bridge arms comprises a plurality of power chips arranged at intervals along a second direction, and each of the power chips is located on one side of the liner; A plurality of first binding wires, wherein in the same group of the bridge arms, any two adjacent power chips are electrically connected via at least one first binding wire, and the first and last two power chips are electrically connected to the metal terminal via at least one first binding wire respectively.

2. The power module according to claim 1, characterized in that: The lining plate comprises an insulating layer and a copper-clad layer located on one side of the insulating layer, wherein the copper-clad layer comprises a first copper-clad layer, a second copper-clad layer, a third copper-clad layer and a fourth copper-clad layer which are arranged at intervals; The metal terminal at least includes a power terminal, and the power terminal includes an AC terminal, a negative DC terminal and a positive DC terminal; wherein the AC terminal is electrically connected to the first copper cladding layer, the negative terminal is electrically connected to the third copper cladding layer, and the positive DC terminal is electrically connected to the fourth copper cladding layer.

3. The power module according to claim 2, characterized in that: The first copper clad layer is close to the first side of the lining board, the third copper clad layer is close to the second side of the lining board, the fourth copper clad layer is close to the second side, the third side and the fourth side of the lining board respectively, and the second copper clad layer is located in the area surrounded by the second copper clad layer and the third copper clad layer; wherein, the first side and the second side are two sides arranged opposite to each other in the second direction, and the third side and the fourth side are two sides arranged opposite to each other in the first direction.

4. The power module according to claim 3, characterized in that: The bridge arm includes at least one upper bridge power chip and at least one lower bridge power chip arranged at intervals along the second direction, the first surface of each upper bridge power chip contacts and forms an electrical connection with the fourth copper cladding layer, and the first surface of each lower bridge power chip contacts and forms an electrical connection with the second copper cladding layer; wherein, In each group of the bridge arms, in the second direction, the second surface of the upper bridge power chip close to the first copper clad layer is electrically connected to the first copper clad layer through at least one binding wire, the second surface of the upper bridge power chip close to the second copper clad layer is electrically connected to the second copper clad layer through at least one first binding wire, and the second surface of the lower bridge power chip close to the third copper clad layer is electrically connected to the third copper clad layer through at least one first binding wire.

5. The power module according to claim 2, characterized in that: The copper clad layer further includes a fifth copper clad layer, a sixth copper clad layer and a seventh copper clad layer which are arranged at intervals; the metal terminal further includes a signal terminal located at the first side of the liner, and the signal terminal at least includes a lower bridge source terminal, an upper bridge drain terminal, an upper bridge gate terminal, an upper bridge source terminal and a lower bridge gate terminal; wherein, The lower bridge source terminal is electrically connected to the fifth copper clad layer, the upper bridge gate terminal is electrically connected to the sixth copper clad layer, the upper bridge drain terminal is electrically connected to the fourth copper clad layer, the upper bridge source terminal is electrically connected to the first copper clad layer, and the lower bridge gate terminal is electrically connected to the seventh copper clad layer.

6. The power module according to claim 5, characterized in that: The fifth copper clad layer is close to the third side of the lining board and adjacent to the fourth copper clad layer, a portion of the sixth copper clad layer is located in the gap between the first copper clad layer and the fourth copper clad layer, and the seventh copper clad layer is close to the fourth side and adjacent to the fourth copper clad layer; wherein the fifth copper clad layer and the seventh copper clad layer are symmetrically arranged along the second direction.

7. The power module according to claim 5, characterized in that: The bridge arm includes at least one upper bridge power chip and at least one lower bridge power chip arranged at intervals along the second direction; wherein, The power module also includes multiple second binding wires, the fifth copper clad layer is electrically connected to the third copper clad layer through at least one of the second binding wires, the gate of each of the upper bridge power chips is electrically connected to the sixth copper clad layer through at least one of the second binding wires, and the gate of each of the lower bridge power chips is electrically connected to the seventh copper clad layer through at least one of the second binding wires.

8. The power module according to claim 7, characterized in that: The power module further includes at least one upper bridge gate resistor and at least one lower bridge gate resistor; wherein, The upper bridge gate resistor is located between a plurality of adjacent upper bridge power chips, a first end of the upper bridge gate resistor is electrically connected to the gates of the plurality of adjacent upper bridge power chips through a plurality of the second binding wires, and a second end of the upper bridge gate resistor is electrically connected to the sixth copper clad layer through at least one of the second binding wires; The lower bridge gate resistor is located between multiple adjacent lower bridge power chips, the first end of the lower bridge gate resistor is electrically connected to the gates of the multiple adjacent lower bridge power chips through multiple second binding wires, and the second end of the lower bridge gate resistor is electrically connected to the seventh copper cladding layer through at least one second binding wire.

9. The power module according to any one of claims 1 to 8, characterized in that: The power module also includes: A first pre-coated silver layer is located between the power chip and the liner; A second pre-coated silver layer is located on a side of the power chip away from the first pre-coated silver layer; The copper foil layer is located on a side of the second pre-coated silver layer away from the power chip; wherein part of the first binding wires are respectively connected to the copper foil layer and the liner, so that part of the port of the power chip is electrically connected to the metal terminal.

10. The power module according to any one of claims 1 to 8, characterized in that: The power module also includes a heat dissipation base plate, which includes a heat dissipation substrate and a plurality of diamond-shaped heat dissipation pin fins. The heat dissipation substrate is located on a side of the liner away from the power chip, and each of the diamond-shaped heat dissipation pin fins is located on a side of the heat dissipation substrate close to the liner.

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