CN222483357U

CN222483357U - IGBT power module

Info

Publication number: CN222483357U
Application number: CN202420953066.1U
Authority: CN
Inventors: 胡鑫; 曹连鹏; 任平志
Original assignee: Gezhida Intelligent Technology Jiangsu Co ltd
Current assignee: Gezhida Intelligent Technology Jiangsu Co ltd
Priority date: 2024-04-30
Filing date: 2024-04-30
Publication date: 2025-02-14
Anticipated expiration: 2034-04-30

Abstract

The utility model discloses an IGBT power module, including an IGBT chip, a connection structure, a cooling substrate and a packaging structure; wherein the connection structure includes a first welding layer, a second welding layer and a DBC ceramic sheet, the two sides of the DBC ceramic sheet are respectively connected to the first welding layer and the second welding layer, the first welding layer is connected to the IGBT chip; the cooling substrate is connected to the second welding layer; the packaging structure packages the IGBT chip and the connection structure on the cooling substrate. In this way, the structural connection strength between the DBC ceramic sheet and the IGBT chip and the cooling substrate located on both sides thereof is high, ensuring the reliability and durability of the IGBT power module. On this basis, the IGBT chip can quickly conduct heat to the cooling substrate through the first welding layer, the DBC ceramic sheet and the second welding layer. Compared with the heat conduction solution using thermal grease, the heat dissipation efficiency and the maximum tolerable temperature of the IGBT power module in the utility model are higher.

Description

IGBT power module

Technical Field

The utility model relates to the technical field of power semiconductors, in particular to an IGBT power module.

Background

In an electric drive ECU (Engine Control Unit-engine control unit) power device, an IGBT (Insulated Gate Bipolar Transistor-insulated gate bipolar transistor) is used as a power switch device, and the current of a motor can be regulated, so that the speed and the torque of the motor are controlled. The IGBT is a compound full-control voltage-driven power semiconductor device composed of a BJT (bipolar transistor) and a MOS (insulated gate field effect transistor), and has the advantages of high input impedance of the MOSFET and low conduction voltage drop of the GTR.

The current IGBT power module generally comprises a cooling substrate, a DBC ceramic plate (Direct Bonded Copper-directly bonded with copper) and an IGBT chip, wherein the DBC ceramic plate has the functions of structural connection, heat conduction and insulation, the cooling substrate is connected to one side of the DBC ceramic plate through heat conduction silicone grease, the IGBT chip is connected to the other side of the DBC ceramic plate through solder paste and packaged, the structural heat conduction performance is insufficient, the IGBT power module is only suitable for a low-voltage low-power density IGBT platform scheme, and the highest bearable temperature of the IGBT power module is low.

Disclosure of utility model

The utility model mainly aims to provide an IGBT power module which aims to improve heat dissipation performance.

To achieve the above object, the present utility model provides an IGBT power module, comprising:

an IGBT chip;

The connecting structure comprises a first welding layer, a second welding layer and a DBC ceramic plate, wherein two sides of the DBC ceramic plate are respectively connected with the first welding layer and the second welding layer, and the first welding layer is connected with the IGBT chip;

A cooling substrate connected to the second solder layer, and

And the IGBT chip and the connecting structure are packaged on the cooling substrate by the packaging structure.

In some embodiments of the utility model, the first solder layer is a tin sheet, silver-based solder, or copper-based solder.

In some embodiments of the utility model, the second solder layer is a tin sheet, silver-based solder, or copper-based solder.

In some embodiments of the present utility model, the DBC ceramic chip has a ceramic layer, and a first copper layer and a second copper layer connected to two sides of the ceramic layer, where the first copper layer is connected to the first soldering layer, the second copper layer is connected to the second soldering layer, the second soldering layer is a copper-tin alloy tin sheet, and the material of the cooling substrate is copper.

In some embodiments of the present utility model, the first copper layer includes an electrical connection portion and a soldering portion, the IGBT chip and the electrical connection portion are connected by a metal bonding wire, the IGBT chip and the soldering portion solder the first copper layer and the first soldering layer, and the first soldering layer is a lead-tin alloy tin sheet.

In some embodiments of the utility model, the weld is the same shape and size as the first weld layer.

In some embodiments of the utility model, the second copper layer is the same shape and size as the second solder layer.

In some embodiments of the utility model, the cooling substrate is made of copper.

In some embodiments of the utility model, the encapsulation structure is a silicone gel.

In some embodiments of the utility model, the IGBT power module further comprises a housing covering one side of the cooling substrate, the silicone gel being located within the housing.

In some embodiments of the utility model, a void is formed between the housing and the silicone gel.

In the scheme of the utility model, a first welding layer and a second welding layer are respectively arranged on two sides of a DBC ceramic plate in a connecting structure, the first welding layer is connected with an IGBT chip, a cooling substrate is connected with the second welding layer, and the IGBT chip and the DBC ceramic plate are packaged in a packaging structure. Therefore, the structural connection strength of the DBC ceramic chip and the IGBT chips and the cooling substrate which are respectively positioned at the two sides of the DBC ceramic chip is high, and the reliability and the durability of the IGBT power module are ensured. On the basis, the IGBT chip can rapidly conduct heat to the cooling substrate through the first welding layer, the DBC ceramic chip and the second welding layer, and compared with the heat conduction scheme adopting the heat conduction silicone grease, the heat dissipation efficiency and the highest bearable temperature of the IGBT power module are higher.

Drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, and it is obvious that the drawings in the following description are only some embodiments of the present utility model, and other drawings may be obtained from the structures shown in these drawings without the need of inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural diagram of an embodiment of an IGBT power module according to the present utility model.

Reference numerals illustrate:

1. The IGBT power module comprises an IGBT chip, an IGBT 11, a metal bonding wire, 20, a DBC ceramic chip, 21, a first copper layer, 211, an electric connection part, 212, a welding part, 22, a second copper layer, 23, a ceramic layer, 30, a cooling substrate, 40, a packaging structure, 50, a first welding layer, 60, a second welding layer, 70, a shell, 80 and a gap.

The achievement of the objects, functional features and advantages of the present utility model will be further described with reference to the accompanying drawings, in conjunction with the embodiments.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that, if directional indications (such as up, down, left, right, front, and rear are referred to in the embodiments of the present utility model), the directional indications are merely used to explain the relative positional relationship, movement conditions, and the like between the components in a specific posture, and if the specific posture is changed, the directional indications are correspondingly changed.

In addition, if there is a description of "first", "second", etc. in the embodiments of the present utility model, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, if "and/or" and/or "are used throughout, the meaning includes three parallel schemes, for example," a and/or B "including a scheme, or B scheme, or a scheme where a and B are satisfied simultaneously. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

The utility model provides an IGBT power module 1, which comprises an IGBT chip 10, a connecting structure, a cooling substrate 30 and a packaging structure 40, wherein the connecting structure comprises a first welding layer 50, a second welding layer 60 and a DBC ceramic chip 20, two sides of the DBC ceramic chip 20 are respectively connected with the first welding layer 50 and the second welding layer 60, the first welding layer 50 is connected with the IGBT chip 10, the cooling substrate 30 is connected with the second welding layer 60, and the packaging structure 40 packages the IGBT chip 10 and the connecting structure on the cooling substrate 30.

The IGBT chip 10 is used in connection with a motor to regulate the current of the motor to control the speed and torque of the motor. The DBC ceramic chip 20 has the functions of structural connection, heat conduction and insulation, has excellent heat conduction performance and electrical insulation performance, and can meet the heat dissipation and insulation requirements of high-power electronic devices like the IGBT chip 10.

The first welding layer 50 connects the IGBT chip 10 and the DBC ceramic chip 20 by gas welding, ultrasonic welding, laser welding, and the like, preferably, formic acid furnace fusion welding is adopted, and the formic acid furnace can provide a certain amount of hydrogen, so that the hydrogen can react with oxygen in the welding process, and the formation of oxides is reduced, thereby maintaining the purity of a welding seam and a molten pool, protecting a welding area from being polluted by oxygen, and improving the welding quality and efficiency. The second soldering layer 60 is similar to the soldering manner of the first soldering layer 50, and may be formed by soldering in a formic acid furnace, and the first soldering layer 50 and the second soldering layer 60 may be made of the same material or different materials, specifically may be tin sheet, silver-based solder or copper-based solder, and may be selected for different substrates.

In the manner of fusion welding by using a formic acid furnace, different furnace temperatures are generally adopted to adapt to the first welding layer 50 and the second welding layer 60 which are made of different materials and have different melting points, for example, the first welding layer 50 is made of lead-tin alloy tin sheet, the furnace temperature of the formic acid furnace is set at 240 ℃ to 245 ℃, and can be 240 ℃, 241 ℃, 242 ℃, 243 ℃ and 245 ℃, and for example, the furnace temperature of the second welding layer 60 is set at 270 ℃ to 280 ℃, can be 270 ℃, 272 ℃, 275 ℃, 278 ℃ and 280 ℃.

The cooling substrate 30 is generally a copper plate, has good heat conduction performance, high strength, high temperature resistance and electromagnetic interference resistance, and the cooling substrate 30 is generally a water cooling mode, so that the cooling efficiency is high. Of course, the cooling substrate 30 may be made of other metal materials, and the cooling method may be an air cooling method. The encapsulation structure 40 may be a silicone gel or an epoxy resin, and is not limited herein, and may be provided according to circumstances.

In the present utility model, a first solder layer 50 and a second solder layer 60 are respectively disposed on two sides of the DBC ceramic chip 20 in the connection structure, the first solder layer 50 is connected to the IGBT chip 10, the cooling substrate 30 is connected to the second solder layer 60, and the package structure 40 packages the IGBT chip 10 and the DBC ceramic chip 20 on the cooling substrate 30. In this way, the structural connection strength between the DBC ceramic chip 20 and the IGBT chip 10 and the cooling substrate 30 respectively located on both sides thereof is high, and the reliability and durability of the IGBT power module 1 are ensured. On this basis, the IGBT chip 10 is capable of rapidly conducting heat to the cooling substrate 30 through the first bonding layer 50, the DBC ceramic sheet 20, and the second bonding layer 60, and the heat dissipation efficiency and the highest sustainable temperature of the power module are high.

In some embodiments of the present utility model, the DBC ceramic chip 20 has a ceramic layer 23, and a first copper layer 21 and a second copper layer 22 respectively connected to two sides of the ceramic layer 23, wherein the first copper layer 21 is connected to the first bonding layer 50, the second copper layer 22 is connected to the second bonding layer 60, the second bonding layer 60 is a copper-tin alloy tin sheet, and the cooling substrate 30 is made of copper. The use of copper-tin alloy tin sheet for soldering the first copper layer 21 and the cooling substrate 30 is excellent in effect and high in structural strength.

In some embodiments of the present utility model, the periphery of the ceramic layer 23 extends beyond the first copper layer 21 and the second copper layer 22 to ensure an insulating effect.

In some embodiments of the present utility model, the first copper layer 21 includes an electrical connection portion 211 and a soldering portion 212, the IGBT chip 10 and the electrical connection portion 211 are connected by a metal bonding wire 11, the IGBT chip 10 and the soldering portion 212 are soldered to the first copper layer 21 and the first soldering layer 50, and the first soldering layer 50 is a tin plate of lead-tin alloy. The cost of welding the IGBT chip 10 and the welding portion 212 by using the lead-tin alloy sheet is low, the welding process is stable, and the controllability is good.

Considering that the welding portion 212 and the first welding layer 50 are not matched in shape or not equal in size, and can be connected only by their own partial structures, the heat conduction cross-sectional area is also small, and the heat dissipation is poor, so that in some embodiments of the present utility model, the welding portion 212 and the first welding layer 50 are identical in shape and equal in size. Similarly, in other embodiments of the present utility model, the second copper layer 22 is the same shape and size as the second solder layer 60. Thereby ensuring the connection strength and the heat conduction effect.

In some embodiments of the present utility model, the encapsulation structure 40 is a silicone gel. Thus, the package structure 40 has better insulation performance and high temperature resistance. In some embodiments of the utility model, the cooling base plate 30 is a water cooled plate.

Further, in some embodiments of the present utility model, the IGBT power module 1 further includes a housing 70, the housing 70 covers one side of the cooling substrate 30, and the silicone gel is located in the housing 70. To improve the protection performance of the IGBT power module 1.

In some embodiments of the utility model, a void 80 is formed between the housing 70 and the silicone gel. To avoid silicone gel from spilling out of the housing 70 during encapsulation.

The foregoing description is only exemplary embodiments of the present utility model and is not intended to limit the scope of the utility model, and all equivalent structural changes made by the description of the present utility model and the accompanying drawings or direct/indirect application in other related technical fields are included in the scope of the present utility model.

Claims

1. An IGBT power module, comprising:

an IGBT chip;

A cooling substrate connected to the second solder layer, and

2. The IGBT power module of claim 1 wherein the first solder layer is a tin sheet, silver-based solder, or copper-based solder, and/or,

The second welding layer is tin sheet, silver-based solder or copper-based solder.

3. The IGBT power module of claim 1 wherein the DBC ceramic chip has a ceramic layer and a first copper layer and a second copper layer respectively connected to both sides of the ceramic layer, the first copper layer is connected to the first solder layer, the second copper layer is connected to the second solder layer, the second solder layer is a copper-tin alloy tin sheet, and the cooling substrate is made of copper.

4. The IGBT power module of claim 3 wherein the first copper layer comprises an electrical connection and a solder, the IGBT die and the electrical connection being connected by a metal bond wire, the IGBT die and the solder soldering the first copper layer to the first solder layer, the first solder layer being a tin sheet of lead-tin alloy.

5. The IGBT power module of claim 4 wherein the solder is the same shape and equal size as the first solder layer.

6. The IGBT power module of claim 3 wherein the second copper layer is the same shape and size as the second solder layer.

7. The IGBT power module of claim 1 wherein the cooling substrate is a water cooled plate.

8. The IGBT power module of claim 1 wherein the encapsulation structure is a silicone gel.

9. The IGBT power module of claim 8 further comprising a housing covering one side of the cooling substrate, the silicone gel being located within the housing.

10. The IGBT power module of claim 9 wherein a void is formed between the housing and the silicone gel.