Insulating substrate and power module

Abstract

The application provides an insulating substrate and a power module, the insulating substrate comprises a metal layer, an insulating layer and a connecting layer, the insulating layer is arranged between the metal layer and the connecting layer, the connecting layer is used for connecting a heat dissipation bottom plate of the power module, the metal layer is provided with an upper bridge arm and a lower bridge arm, the upper bridge arm and the lower bridge arm are used for mounting power chips, and the current directions of the upper bridge arm and the lower bridge arm are opposite. The application has the beneficial effect that the stray inductance of the power module can be reduced.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and more specifically, to an insulating substrate and a power module. Background Technology

[0002] The power chip is the "heart" of the inverter, while the power module is the "skeleton" of the power chip, forming the core component for protecting and realizing the inverter function. In the passenger vehicle sector, in recent years, some high-performance models have been the first to adopt 800V electric drive systems, thereby promoting the large-scale application of new energy vehicles. Under an 800V electric drive system, the maximum withstand voltage of the power chip is 1200V. In the use of power chips, the following relationship between the bus voltage and the maximum withstand voltage must generally be met to prevent the power chip from breaking down: bus voltage (800V) + overshoot voltage (L*di / dt, where L is stray inductance) < maximum withstand voltage of the power chip (1200V). However, currently, power modules often have high stray inductance, making the power chip more susceptible to breakdown. Summary of the Invention

[0003] The present invention aims to at least partially solve the technical problem of how to reduce the stray inductance of power modules.

[0004] The present invention provides an insulating substrate, comprising a metal layer, an insulating layer, and a connecting layer. The insulating layer is disposed between the metal layer and the connecting layer. The connecting layer is used to connect a heat dissipation base plate of a power module. The metal layer has an upper bridge arm and a lower bridge arm, which are used to mount power chips. The current passing through the upper bridge arm and the lower bridge arm is in opposite directions.

[0005] The insulating substrate of this invention comprises a three-layer structure. The metal layer forms the circuit layout layer on the surface, which carries the input and output current of the power module when the insulating substrate is applied to the power module. The middle layer is an insulating layer, which serves as an insulating and protective layer. The connecting layer on the other surface is used for sintering and interconnection with the heat dissipation base plate of the power module. The metal layer is provided with an upper bridge arm and a lower bridge arm, both of which are used to mount power chips, thus serving as carriers for the power chips. When applied to the power module, current flows from the upper bridge arm to the lower bridge arm, thereby realizing the input and output of current. When current is conducted, the current directions in the upper and lower bridge arms are opposite. Therefore, the setting of two sets of reverse current paths can increase the mutual inductance between the DC terminals in the power module, thereby reducing the stray inductance when applied to the power module, thus reducing the overshoot voltage and better preventing the chip from being damaged.

[0006] Furthermore, the upper bridge arm includes a first arm and a second arm arranged side by side, and the lower bridge arm includes a third arm and a fourth arm arranged side by side. The third arm and the fourth arm are located between the first arm and the second arm, and the first arm, the second arm, the third arm and the fourth arm are all used to mount the power chip.

[0007] Furthermore, the upper bridge arm also includes a first connecting portion, and the lower bridge arm also includes a second connecting portion. The first arm and the second arm are connected through the first connecting portion, and the third arm and the fourth arm are connected through the second connecting portion.

[0008] Furthermore, the first arm and the second arm are arranged symmetrically with respect to the calibration reference line, and the third arm and the fourth arm are arranged symmetrically with respect to the calibration reference line.

[0009] Furthermore, the first arm and the third arm are arranged adjacent to each other at a distance, and the second arm and the fourth arm are arranged adjacent to each other at a distance. The portion of the metal layer between the first arm and the third arm, and the portion between the second arm and the fourth arm, are provided with an upper bridge arm gate contact region and an upper bridge arm source contact region. The portion of the metal layer between the third arm and the fourth arm is provided with a lower bridge arm gate contact region and a lower bridge arm source contact region. The upper bridge arm gate contact region and the lower bridge arm gate contact region are used to install gate resistors, and the upper bridge arm source contact region and the lower bridge arm source contact region are used to connect to the power chip.

[0010] Furthermore, the portion of the metal layer located between the upper bridge arm and the lower bridge arm is also provided with a power terminal mounting structure. The lower bridge arm is used to communicate with the power terminal mounting structure, and the end of the upper bridge arm and the power terminal mounting structure away from the lower bridge arm is used to install power terminals respectively.

[0011] Furthermore, the power terminal mounting structure includes two elongated structures and a third connecting portion for connecting the two elongated structures. The two elongated structures are arranged side by side between the third arm and the fourth arm, and the two elongated structures are respectively connected to the third arm and the fourth arm. The end of the third connecting portion, the first arm, and the second arm away from the lower bridge arm is used to install power terminals respectively.

[0012] The present invention also proposes a power module comprising the insulating substrate described above.

[0013] The power module in this invention has similar technical effects to the aforementioned insulating substrate, and will not be described in detail here.

[0014] Furthermore, the power module also includes an AC terminal, a DC+ terminal, and a DC- terminal. The DC+ terminal is connected to the upper bridge arm of the insulating substrate, the AC terminal is connected to the lower bridge arm of the insulating substrate, and the DC- terminal is connected to the power terminal mounting structure of the insulating substrate.

[0015] Furthermore, the power module also includes power chips. Multiple power chips are provided at both the upper bridge arm and the lower bridge arm of the insulating substrate. The multiple power chips at the upper bridge arm and the multiple power chips at the lower bridge arm are evenly spaced along the calibration direction.

[0016] Furthermore, the power chips at the upper bridge arm are all connected to the lower bridge arm via multiple wires, and the power chips at the lower bridge arm are all connected to the power terminal mounting structure of the insulating substrate via multiple wires. The multiple wires connecting the same power chip are parallel to each other, and at least two wires connecting different power chips are parallel to each other. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the metal layer structure of the insulating substrate according to an embodiment of the present invention;

[0018] Figure 2 This is a schematic diagram of the power module described in an embodiment of the present invention;

[0019] Figure 3 This is a diagram showing the current flow direction of the power module described in an embodiment of the present invention when it is powered on.

[0020] Explanation of reference numerals in the attached figures:

[0021] 1-Metal layer; 2-Power chip; 3-Gate resistor; 4-Wire; 5-AC terminal; 6-DC+ terminal; 7-DC- terminal; 8-Thermistor; 101-Upper bridge arm; 102-Lower bridge arm; 103-Gate contact area of ​​upper bridge arm; 104-Source contact area of ​​upper bridge arm; 105-Gate contact area of ​​lower bridge arm; 106-Source contact area of ​​lower bridge arm; 107-Power terminal mounting structure; 117-Strip structure; 127-Third connection part; 108-Thermistor contact circuit; 111-First arm; 112-Third arm; 121-Second arm; 122-Fourth arm; 131-First connection part; 132-Second connection part. Detailed Implementation

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in sequences other than those illustrated or described herein.

[0024] In the description of this specification, references to terms such as "embodiment," "one embodiment," and "one implementation" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or implementation is included in at least one embodiment or illustrative implementation of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or implementation. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or implementations.

[0025] Combination Figure 1 As shown in the figure, an embodiment of the present invention proposes an insulating substrate, including a metal layer 1, an insulating layer and a connecting layer. The insulating layer is disposed between the metal layer 1 and the connecting layer. The connecting layer is used to connect the heat dissipation base plate of the power module. The metal layer 1 is provided with an upper bridge arm 101 and a lower bridge arm 102. The upper bridge arm 101 and the lower bridge arm 102 are used to mount the power chip 2. The current passing through the upper bridge arm 101 and the lower bridge arm 102 is in opposite directions.

[0026] In this embodiment, the insulating substrate has a three-layer structure. The metal layer 1 forms the circuit layout layer on the surface and is used to carry the input and output current of the power module when the insulating substrate is applied to the power module. The middle layer is an insulating layer, specifically a ceramic insulating layer, which plays the role of insulation and isolation protection. The connecting layer on the other surface is used for sintering and interconnection with the heat dissipation base plate of the power module. The connecting layer can be made of metal material.

[0027] The metal layer 1 includes an upper bridge arm 101 and a lower bridge arm 102. In an optional embodiment, the upper bridge arm 101 and the lower bridge arm 102 can be formed by etching on the metal layer 1. Both the upper bridge arm 101 and the lower bridge arm 102 are used to mount the power chip 2, serving as the carrier for the power chip 2. It is understood that when applied to a power module, current flows from the upper bridge arm 101 to the lower bridge arm 102. Specifically, the upper bridge arm 101 and the lower bridge arm 102 can respectively conduct the bus capacitor through power terminals, thereby realizing current input and output. In this embodiment, when the upper bridge arm 101 and the lower bridge arm 102 conduct current, the current directions in the upper bridge arm 101 and the lower bridge arm 102 are opposite (e.g., ...). Figure 1(in the direction of the middle arrow). Thus, the setting of two sets of reverse current paths increases the mutual inductance between the DC terminals in the power module, thereby reducing stray inductance when applied to the power module, thereby reducing overshoot voltage and better preventing chip breakdown.

[0028] In an optional embodiment, the metal layer can be made of copper or copper alloys, or other metals or alloys with good conductivity.

[0029] In an optional embodiment of the present invention, the upper bridge arm 101 includes a first arm 111 and a second arm 121 arranged side by side, and the lower bridge arm 102 includes a third arm 112 and a fourth arm 122 arranged side by side. The third arm 112 and the fourth arm 122 are located between the first arm 111 and the second arm 121. The first arm 111, the second arm 121, the third arm 112 and the fourth arm 122 are all used to mount the power chip 2.

[0030] Reference Figure 1 In this embodiment, the first arm 111 and the second arm 121 are located on the periphery of the metal layer 1, while the third arm 112 and the fourth arm 122 are located on the inner side of the metal layer 1, forming an upper bridge arm 101 surrounding the lower bridge arm 102. That is, the first arm 111, the third arm 112, the fourth arm 122, and the second arm 121 are arranged side by side with intervals. With the current conduction directions opposite, the distance between each arm can be set closer. Through this layout, the commutation circuits with opposite current directions are closer, which can further increase the mutual inductance between the DC terminals in the power module to reduce stray inductance. At the same time, both the upper bridge arm 101 and the lower bridge arm 102 are double-arm forms, so the commutation circuit is increased to two, the circuit mutual inductance is greater, and correspondingly, the stray inductance is smaller.

[0031] In an optional embodiment of the present invention, the upper bridge arm 101 further includes a first connecting portion 131, the lower bridge arm 102 further includes a second connecting portion 132, the first arm 111 and the second arm 121 are connected through the first connecting portion 131, and the third arm 112 and the fourth arm 122 are connected through the second connecting portion 132.

[0032] In this embodiment, the first arm 111 and the second arm 121 of the upper bridge arm 101, and the third arm 112 and the fourth arm 122 of the lower bridge arm 102 are all along... Figure 1The upper bridge arm 101 is vertically arranged in the vertical direction. At this time, the upper bridge arm 101 also includes a horizontally arranged first connecting part 131, which is located at the bottom. The lower bridge arm 102 also includes a horizontally arranged second connecting part 132, which is located at the top. In this way, the first arm 111 and the second arm 121 are connected through the first connecting part 131, and the third arm 112 and the fourth arm 122 are connected through the second connecting part 132. Thus, the upper bridge arm 101 and the lower bridge arm 102 each form a whole. This is beneficial for the more uniform current when the power chip 2 is installed on the upper bridge arm 101 and the lower bridge arm 102. The connection between the two arms also makes the electrical signal input more synchronized and the reliability better. It prevents the influence of the external control power supply from causing a time difference in the electrical signal input, which ultimately affects the switching performance of the power module.

[0033] In an optional embodiment of the present invention, the first arm 111 and the second arm 121 are arranged axially symmetrically with respect to the calibration reference line, and the third arm 112 and the fourth arm 122 are arranged axially symmetrically with respect to the calibration reference line.

[0034] In this embodiment, the calibration baseline is a virtual line set manually, such as... Figure 1 The dashed lines in the diagram do not represent the actual presence of the calibration reference line in the insulating substrate. The upper bridge arm 101 and the lower bridge arm 102 are configured as a symmetrical structure. Specifically, the first arm 111 and the second arm 121 are axially symmetrical with respect to the calibration reference line, and the third arm 112 and the fourth arm 122 are axially symmetrical with respect to the calibration reference line. This makes the current passing through the same upper bridge arm 101 or lower bridge arm 102 more synchronous and uniform, and also makes the current flowing from the upper bridge arm 101 to the lower bridge arm 102 more synchronous, thereby further reducing stray inductance.

[0035] In addition, based on this symmetrical arrangement, the power chips 2 installed on the first arm 111, the second arm 121, the third arm 112 and the fourth arm 122 are symmetrically distributed, thereby minimizing the thermal coupling effect and allowing heat to be dissipated at the fastest speed, resulting in better thermal performance and improved reliability of the power module.

[0036] In an optional embodiment of the present invention, the first arm 111 and the third arm 112 are arranged adjacent to each other at a distance, and the second arm 121 and the fourth arm 122 are arranged adjacent to each other at a distance. The portion of the metal layer 1 between the first arm 111 and the third arm 112 and the portion between the second arm 121 and the fourth arm 122 are provided with an upper bridge arm gate contact region 103 and an upper bridge arm source contact region 104. The portion of the metal layer 1 between the third arm 112 and the fourth arm 122 is provided with a lower bridge arm gate contact region 105 and a lower bridge arm source contact region 106. The upper bridge arm gate contact region 103 and the lower bridge arm gate contact region 105 are used to mount the gate resistor 3, and the upper bridge arm source contact region 104 and the lower bridge arm source contact region 106 are used to connect the power chip 2.

[0037] Reference Figure 1 As shown, in this embodiment, the first arm 111 of the upper bridge arm 101 is adjacent to the third arm 112 of the lower bridge arm 102, and the second arm 121 is adjacent to the fourth arm 122. The structure of the metal layer 1 between them is divided into an upper bridge arm gate contact region 103 and an upper bridge arm source contact region 104. Correspondingly, the structure of the metal layer 1 between the third arm 112 and the fourth arm 122 is divided into a lower bridge arm gate contact region 105 and a lower bridge arm source contact region 106. The upper bridge arm gate contact region 103 and the lower bridge arm gate contact region 105 are both used to install gate resistors 3, thereby adjusting the switching characteristics, oscillation characteristics, and power consumption characteristics of the power module. The upper bridge arm source contact region 104 and the lower bridge arm source contact region 106 are used to connect the power chip 2 through wires to achieve conduction, which facilitates subsequent control of the power chip 2, such as driving the power chip 2 to switch on and off.

[0038] Specifically, in this embodiment, the upper bridge arm gate contact region 103, the lower bridge arm gate contact region 105, the upper bridge arm source contact region 104, and the lower bridge arm source contact region 106 are all elongated strips, arranged side by side with the arm portions of the upper bridge arm 101 and the lower bridge arm 102. When the power chip 2 is installed at the upper bridge arm 101 and the lower bridge arm 102, gate resistors 3 are installed at adjacent positions on the upper bridge arm gate contact region 103 and the lower bridge arm gate contact region 105, thereby connecting to the power chip 2 to achieve conduction. The adjacent positions on the upper bridge arm source contact region 104 and the lower bridge arm source contact region 106 are connected to the control terminal of the power chip 2 through wires, thereby facilitating subsequent control.

[0039] In an optional embodiment of the present invention, the portion of the metal layer 1 located between the upper bridge arm 101 and the lower bridge arm 102 is further provided with a power terminal mounting structure 107, and the power terminal mounting structure 107 is used to conduct electricity with the lower bridge arm 102. The ends of the upper bridge arm 101 and the power terminal mounting structure 107 located away from the lower bridge arm 102 are respectively used to connect power terminals. Specifically, the upper bridge arm 101 is used to connect to the DC+ terminal 6, and the power terminal mounting structure 107 is used to connect to the DC- terminal 7. Therefore, the current entering from the upper bridge arm 101, which is away from the lower bridge arm 102, flows towards the lower bridge arm 102. After the current is introduced into the lower bridge arm 102, the current in the lower bridge arm 102 flows into the power terminal mounting structure 107 and flows to the end of the power terminal mounting structure 107 away from the lower bridge arm 102, and finally flows into the DC terminal 7. Thus, by forming this round-trip current flow pattern, the current flowing in the upper bridge arm 101 and the lower bridge arm 102 is opposite, thereby reducing stray inductance.

[0040] In an optional embodiment of the present invention, the power terminal mounting structure 107 includes two strip structures 117 and a third connecting portion 127 for connecting the two strip structures 117. The two strip structures 117 are arranged side by side between the third arm 112 and the fourth arm 122, and the two strip structures 117 are respectively connected to the third arm 112 and the fourth arm 122. The end of the third connecting portion 127, the first arm 111, and the second arm 121 away from the lower bridge arm 102 is used to install power terminals respectively.

[0041] In this embodiment, both the third arm 112 and the fourth arm 122 are used to conduct electricity with the power terminal mounting structure 107. It can be understood that when power chips 2 are provided at the first arm 111, the second arm 121, the third arm 112, and the fourth arm 122, the power chips 2 at the first arm 111 and the second arm 121 are connected to the third arm 112 and the fourth arm 122 through wires. The power chips 2 at the third arm 112 and the fourth arm 122 are connected to the power terminal mounting structure 107, thereby realizing the current conduction from the first arm 111 and the second arm 121 to the third arm 112 and the fourth arm 122, and the current conduction from the third arm 112 and the fourth arm 122 to the power terminal mounting structure 107.

[0042] In this invention, when the insulating substrate is used in a power module, the ends of the first arm 111 and the second arm 121 furthest from the lower bridge arm 102 are used to mount the DC+ terminal 6 for current input, such as... Figure 1 and Figure 2In this embodiment, the lower ends of the first arm 111 and the second arm 121 are respectively connected to a DC+ terminal 6 to achieve synchronous current input. To facilitate the conduction of multiple power chips 2 to the power terminal mounting structure 107 at the lower bridge arm 102, the power terminal mounting structure 107 has a strip-shaped structure 117 parallel to the third arm 112 and the fourth arm 122 of the lower bridge arm 102, for connection to the power chips at the third arm 112 and the fourth arm 122 respectively. A third connecting portion 127 is used below the two strip-shaped structures 117. This third connecting portion 117, i.e., the end of the power terminal mounting structure 107 away from the lower bridge arm 102, is used to mount the DC- terminal 7, thus forming a complete current loop. Therefore, referring to… Figure 2 and Figure 3 As shown, through the connection of the upper and lower bridge arms and the conduction between the lower bridge arm 102 and the power terminal mounting structure 107, the current is input from the upper bridge arm 101 and transmitted upwards, flowing to the lower bridge arm 102, and then transmitted downwards at the lower bridge arm 102, and then introduced into the power terminal mounting structure 107, finally flowing out from the DC-terminal 7 connected to the power terminal mounting structure 107, ultimately forming... Figure 3 The current flow pattern shown (where the arrows indicate the current direction) is used to reverse the current flow direction in the upper bridge arm 101 and the lower bridge arm 102, thereby reducing stray inductance.

[0043] In an optional embodiment, the metal layer 1 is further provided with a thermistor contact circuit 108 for mounting the thermistor 8, thereby facilitating protection of the power module during use.

[0044] Another embodiment of the present invention provides a power module comprising an insulating substrate as described above.

[0045] The power module in this embodiment has similar technical effects to the insulating substrate described above, and will not be described in detail here.

[0046] In an optional embodiment of the present invention, the power module further includes an AC terminal 5, a DC+ terminal 6, and a DC- terminal 7. The DC+ terminal 6 is connected to the upper bridge arm 101 of the insulating substrate, the AC terminal 5 is connected to the lower bridge arm 102 of the insulating substrate, and the DC- terminal 7 is connected to the power terminal mounting structure 107 of the insulating substrate.

[0047] In this embodiment, the first arm 111 and the second arm 121 of the upper bridge arm 101 are respectively connected to the DC+ terminal 6 and the DC- terminal 7 connected to the power terminal mounting structure 107. The DC+ terminal 6 and the DC- terminal 7 are used to connect the bus capacitor to realize power supply, thereby realizing the current conduction from the DC+ terminal 6, the upper bridge arm 101, the lower bridge arm 102, the power terminal mounting structure 107 to the DC- terminal 7. The AC terminal 5 is the AC output terminal, which is used to connect the load, such as the motor, so as to realize the application of the power module.

[0048] In an optional embodiment, DC+ terminal 6 is ultrasonically welded to the first arm 111 and the second arm 121, AC terminal 5 is ultrasonically welded to the lower bridge arm 102, and DC- terminal 7 is ultrasonically welded to the power terminal mounting structure 107. In addition, DC+ terminal 6, DC- terminal 7 and AC terminal are used to connect to the bus capacitor, which can be specifically laser welded. This allows for a significant reduction in the length of each power terminal, effectively shortening the current path and further reducing stray inductance.

[0049] In an optional embodiment of the present invention, the power module further includes power chips 2, and a plurality of power chips 2 are provided at both the upper bridge arm 101 and the lower bridge arm 102 of the insulating substrate, and the plurality of power chips 2 at the upper bridge arm 101 and the plurality of power chips 2 at the lower bridge arm 102 are uniformly spaced along the calibration direction.

[0050] Specifically, in this embodiment, the first arm 111, the second arm 121, the third arm 112, and the fourth arm 122 are all along... Figure 1 The diagram shows four power chips 2 evenly spaced in the vertical direction, for a total of 16 power chips 2. By evenly spacing the power chips 2, and in an optional embodiment, symmetrically arranging the power chips 2 at the first arm 111 and the second arm 121, and symmetrically arranging the power chips 2 at the third arm 112 and the fourth arm 122, the length of the converter circuit is effectively reduced, thereby reducing the stray inductance of the converter circuit and reducing the thermal coupling effect. Heat can be dissipated at the fastest speed, resulting in better thermal performance and improved reliability of the power module.

[0051] The power chip 2 of the upper bridge arm 101 is connected to the lower bridge arm 102 via a wire, and the power chip 2 of the lower bridge arm 102 is connected to the power terminal mounting structure 107, thereby forming a structure as shown in the figure. Figure 3The diagram shows the current flow direction. In addition, the power chip 2 of the upper bridge arm 101 is connected to the gate resistor 3 of the upper bridge arm gate contact area 103 and to the upper bridge arm source contact area 104. The power chip 2 of the lower bridge arm 102 is connected to the gate resistor 3 of the lower bridge arm gate contact area 105 and to the lower bridge arm source contact area 106. This facilitates the adjustment of the switching characteristics, oscillation characteristics, power consumption characteristics of the power module and the control of the turn-on and turn-off of the power chip 2.

[0052] In an optional embodiment, the power chip 2 is laid out in a regular, cornerless manner, which is more conducive to achieving a compact arrangement of the power chip 2 in the same bridge arm, and more effectively reduces the length of the commutation circuit, thereby reducing the stray inductance of the commutation circuit.

[0053] In an optional embodiment of the present invention, the power chips 2 at the upper bridge arm 101 are all connected to the lower bridge arm 102 through multiple wires 4, and the power chips 2 at the lower bridge arm 102 are all connected to the power terminal mounting structure 107 of the insulating substrate through multiple wires 4. The multiple wires 4 connecting the same power chip 2 are parallel to each other, and at least two wires 4 connecting different power chips 2 are parallel to each other.

[0054] Reference Figure 2 As shown, in this embodiment, the power chips 2 at the upper bridge arm 101 are all connected to the lower bridge arm 102 via four copper wires, and the power chips 2 at the lower bridge arm are all connected to the power terminal mounting structure 107 via four copper wires to achieve conduction. The multiple wires connecting the same power chip 2 are grouped together, and the multiple wires in the same group can be parallel to each other, thereby ensuring the parallelism of the current path and the number of parallel segments of the current path. This allows adjacent circuits to generate greater mutual inductance, thereby reducing the stray inductance of the power module. Similarly, wires in different groups can also be parallel to each other, such as multiple groups of wires being parallel, nearly parallel, or partially parallel to each other, thereby maximizing the parallelism of the current path and the number of parallel segments of the current path, further reducing stray inductance.

[0055] While the disclosure is as stated above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the protection scope of this invention.

Claims

1. An insulating substrate, characterized in that, It includes a metal layer (1), an insulating layer and a connecting layer. The insulating layer is disposed between the metal layer (1) and the connecting layer. The connecting layer is used to connect the heat dissipation base plate of the power module. The metal layer (1) is provided with an upper bridge arm (101) and a lower bridge arm (102). The upper bridge arm (101) and the lower bridge arm (102) are used to mount the power chip (2). The current passing through the upper bridge arm (101) and the lower bridge arm (102) is in opposite directions. The upper bridge arm (101) includes a first arm (111) and a second arm (121) arranged side by side, and the lower bridge arm (102) includes a third arm (112) and a fourth arm (122) arranged side by side. The third arm (112) and the fourth arm (122) are located between the first arm (111) and the second arm (121). The first arm (111), the second arm (121), the third arm (112) and the fourth arm (122) are all used to install the power chip (2). The first arm (111) and the second arm (121) are located on the periphery of the metal layer (1), and the third arm (112) and the fourth arm (122) are located on the inner side of the metal layer (1). The upper bridge arm (101) further includes a first connecting part (131), through which the first arm (111) and the second arm (121) are connected; The first arm (111) and the third arm (112) are arranged adjacently and spaced apart, and the second arm (121) and the fourth arm (122) are arranged adjacently and spaced apart. The portion of the metal layer (1) between the first arm (111) and the third arm (112) and the portion between the second arm (121) and the fourth arm (122) are each provided with an upper bridge arm gate contact region (103) and an upper bridge arm source contact region (104). The portion of the metal layer (1) between the third arm (112) and the fourth arm (122) is provided with a lower bridge arm gate contact region (105) and a lower... The bridge arm source contact area (106), the upper bridge arm gate contact area (103) and the lower bridge arm gate contact area (105) are used to install gate resistors (3), and the upper bridge arm source contact area (104) and the lower bridge arm source contact area (106) are used to connect the power chip (2); the upper bridge arm gate contact area (103), the lower bridge arm gate contact area (105), the upper bridge arm source contact area (104) and the lower bridge arm source contact area (106) are all elongated and arranged side by side with the arm portions of the upper bridge arm (101) and the lower bridge arm (102).

2. The insulating substrate according to claim 1, characterized in that, The lower bridge arm (102) also includes a second connecting part (132), through which the third arm (112) and the fourth arm (122) are connected.

3. The insulating substrate according to claim 1, characterized in that, The first arm (111) and the second arm (121) are symmetrically arranged with respect to the calibration reference line, and the third arm (112) and the fourth arm (122) are symmetrically arranged with respect to the calibration reference line.

4. The insulating substrate according to any one of claims 1-3, characterized in that, The portion of the metal layer (1) located between the upper bridge arm (101) and the lower bridge arm (102) is further provided with a power terminal mounting structure (107). The lower bridge arm (102) is used to communicate with the power terminal mounting structure (107). The ends of the upper bridge arm (101) and the power terminal mounting structure (107) that are away from the lower bridge arm (102) are used to install power terminals respectively.

5. The insulating substrate according to claim 4, characterized in that, The power terminal mounting structure (107) includes two strip structures (117) and a third connecting part (127) for connecting the two strip structures (117). The two strip structures (117) are arranged side by side between the third arm (112) and the fourth arm (122), and the two strip structures (117) are respectively connected to the third arm (112) and the fourth arm (122). The end of the third connecting part (127), the first arm (111), and the second arm (121) away from the lower bridge arm (102) is used to install power terminals respectively.

6. A power module, characterized in that, Including the insulating substrate as described in any one of claims 1-5.

7. The power module according to claim 6, characterized in that, It also includes power chips (2), and multiple power chips (2) are provided at both the upper bridge arm (101) and the lower bridge arm (102) of the insulating substrate. The multiple power chips (2) at the upper bridge arm (101) and the multiple power chips (2) at the lower bridge arm (102) are evenly spaced along the calibration direction.

8. The power module according to claim 7, characterized in that, The power chips (2) at the upper bridge arm (101) are all connected to the lower bridge arm (102) through multiple wires (4). The power chips (2) at the lower bridge arm (102) are all connected to the power terminal mounting structure (107) of the insulating substrate through multiple wires (4). The multiple wires (4) connecting the same power chip (2) are parallel to each other, and at least two wires (4) connecting different power chips (2) are parallel to each other.

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