Double-side-welding and single-side-water-cooling IGBT power module and welding process
By adopting double-sided welding process and copper sheet metal connection technology in the IGBT power module, the problem of insufficient connection quality and thermal impact capability of semiconductor power modules in the prior art is solved, and higher electrical reliability and transient thermal stability.
Patent Information
- Application Number
- CN202411528167.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-30
- Publication Date
- 2024-12-20
AI Technical Summary
The existing semiconductor power modules have shortcomings in terms of high power density and high reliability, especially in terms of low efficiency in terms of connection quality and accuracy between chips and between chips and insulating substrates, which is difficult to meet the needs of the new energy vehicle industry.
Design a double-sided welding single-sided water-cooled IGBT power module, using copper sheet metal instead of bonding wires to solder the front of the chip part of the insulated gate bipolar transistor and diode, and connect it to the lead frame through solder to improve electrical Connection reliability and transient thermal shock capability.
By increasing the contact surface of the electrical connection and the heat capacity of the copper sheet metal parts, the electrical connection reliability and transient thermal impact capability of the power module are improved, the temperature fluctuations of the chip are reduced, and the overall reliability performance is improved.
Smart Images
Figure CN119170593A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of electronic devices and relates to an IGBT power module with double-side welding and single-side water cooling and a welding process. Background Art
[0002] At present, semiconductor power modules have been widely used in the new energy vehicle industry. With the continuous development, high power density and high reliability are required for power modules, which requires high reliability in structure and circuit of power modules, such as the instantaneous thermal shock resistance of chips and the reliability of electrical connection on the front of chips. Among them, power semiconductor modules have high requirements on the quality and precision of bonding wires used for connection between chips and between chips and insulating substrates due to the large working current, and the production efficiency is low.
[0003] Therefore, for this purpose, a double-sided welded and single-sided water-cooled IGBT power module and welding process are designed to overcome the above problems. Summary of the invention
[0004] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an IGBT power module and welding process with double-sided welding and single-sided water cooling, which has a simple and reasonable structure, is conducive to improving the power module's ability to withstand transient thermal shock and improving the reliability of the power module's electrical connections, and has a simple process.
[0005] The present invention is implemented through the following technical scheme: an IGBT power module with double-sided welding and single-sided water cooling, comprising a power module body placed on a jig, the power module body consisting of a first insulating substrate and a second insulating substrate arranged opposite to each other, and at least one lead frame is arranged on one side of the first insulating substrate and the second insulating substrate, a semiconductor chip that can be welded on both sides is welded by solder, a first copper sheet metal part and a second copper sheet metal part are welded by solder on the semiconductor chips of the first insulating substrate and the second insulating substrate respectively, the first copper sheet metal part and the second copper sheet metal part are connected to the lead frame by bonding wires and solder respectively; the semiconductor chip comprises an insulated gate bipolar transistor (IGBT) and a diode that can be welded on both sides.
[0006] Preferably, the first insulating substrate and the second insulating substrate are both composed of an upper copper layer, an insulating layer composed of a polymer or ceramic in the middle, and a lower copper layer, which are sintered into one piece.
[0007] Preferably, the first copper sheet metal part and the second copper sheet metal part have a thickness of 0.1 mm-10 mm and are made of copper to facilitate stamping, slotting and bending.
[0008] Preferably, the lead frame is composed of a pad, and pins, a power terminal, and a signal terminal respectively arranged on the pad, and a resistor is connected to the pad via solder.
[0009] Preferably, the resistor connected to the lead frame includes a thermistor and a bonding resistor.
[0010] Preferably, the material of the lead frame is copper, the copper surface may or may not be electroplated, and the electroplated metal is one or more of gold, silver, nickel, and tin.
[0011] Preferably, the solder is lead-free solder paste or tin flake, the printing thickness of the lead-free solder paste is 50-500um, the weight of the solder paste at each solder joint is 0.01-50g, the thickness of the tin flake is 50-500um, and the weight of the tin flake at each solder joint is 0.01-50g.
[0012] A welding process for a double-sided welded and single-sided water-cooled IGBT power module, the welding process comprising the following steps: 1) All double-sided semiconductor chips are welded on the first insulating substrate and the second insulating substrate and cleaned; 2) Assemble the first insulating substrate and the second insulating substrate on the jig, add solder to the corresponding positions of the double-sided soldered semiconductor chip, the first insulating substrate, the second insulating substrate, and the lead frame, and complete the assembly, welding, and cleaning of the first insulating substrate, the second insulating substrate, the first copper sheet metal part, the second copper sheet metal part, the lead frame, and the resistor; 3) bonding the first insulating substrate and the second insulating substrate to each component using bonding wires; 4) Package the bonded power module.
[0013] Preferably, in step 2), the first insulating substrate, the second insulating substrate, the first copper sheet metal part, the second copper sheet metal part and the lead frame are assembled by a jig to ensure the accuracy of the position of each component on the module after welding.
[0014] Preferably, in step 1) and step 2), the maximum temperature of the solder is maintained between 100-400°C.
[0015] The beneficial effects of the present invention are as follows: The power module designed by the present invention adopts the technology of welding and connecting the front power pole of the chip part of the insulated gate bipolar transistor and the diode with copper sheet metal instead of bonding wire, thereby increasing the contact surface of the electrical connection, which is beneficial to improving the reliability of the electrical connection of the main circuit of the power module. The presence of the thermal capacity of the copper sheet metal is beneficial to the chip part of the insulated gate bipolar transistor and the diode to resist transient thermal shock during module operation and reduce the chip junction temperature fluctuation. Therefore, the module has better reliability performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic diagram of the overall structure of the present invention. DETAILED DESCRIPTION
[0017] In order to enable those skilled in the art to more clearly understand the objectives, technical solutions and advantages of the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments.
[0018] In the description of the present invention, it is necessary to understand that the orientation or position relationship indicated by the terms such as "up", "down", "left", "right", "inside", "outside", "horizontal" and "vertical" is based on the orientation or position relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention, rather than indicating or implying that the device or original referred to must have a specific orientation, and therefore cannot be understood as a limitation on the present invention.
[0019] The present invention will be described in detail below with reference to the accompanying drawings: Figure 1 As shown, a double-sided soldered and single-sided water-cooled IGBT power module includes a power module body placed on a jig, the power module body is composed of a first insulating substrate 1 and a second insulating substrate 2 arranged opposite to each other, and at least one lead frame 3 is arranged on one side of the first insulating substrate 1 and the second insulating substrate 2, a semiconductor chip 4 that can be soldered on both sides is soldered by solder 8, a first copper sheet metal part 5 and a second copper sheet metal part 6 are respectively soldered by solder 8 on the semiconductor chip 4 of the first insulating substrate 1 and the second insulating substrate 2, and the first copper sheet metal part 5 and the second copper sheet metal part 6 are respectively connected to the lead frame by bonding wires 9 and solder. The semiconductor chip includes an insulated gate bipolar transistor (IGBT) and a diode that can be soldered on both sides.
[0020] The bonding wires include copper wires and aluminum wires. The first insulating substrate and the second insulating substrate may be DBC boards or IMS boards.
[0021] The first insulating substrate 1 and the second insulating substrate 2 are both composed of an upper copper layer sintered into one, an insulating layer composed of a polymer or ceramic in the middle, and a lower copper layer. The first copper sheet metal part 5 and the second copper sheet metal part 6 are 0.1 mm to 10 mm thick and are made of copper for easy stamping, slotting and bending.
[0022] The lead frame 3 is composed of a pad and pins, power terminals and signal terminals respectively arranged on the pad, and a resistor 7 is also connected to the pad through solder. The resistor 7 connected to the lead frame 3 includes a thermistor and a bonding resistor. The material of the lead frame 3 is preferably copper, and the copper surface may or may not be electroplated. The electroplated metal is composed of one or more of gold, silver, nickel and tin. The material of the lead frame can also be adjusted according to actual conditions and made of other metals without any limitation.
[0023] The solder is lead-free solder paste or tin flake. The printing thickness of the lead-free solder paste is 50-500um, the weight of the solder paste at each solder joint is 0.01-50g, the thickness of the tin flake is 50-500um, and the weight of the tin flake at each solder joint is 0.01-50g.
[0024] A welding process for a double-sided welded and single-sided water-cooled IGBT power module, the welding process comprising the following steps: 1) All double-sided semiconductor chips 4 are welded on the first insulating substrate 1 and the second insulating substrate 2 and then cleaned; 2) Assemble the first insulating substrate 1 and the second insulating substrate 2 on the jig, add solder 8 to the corresponding positions of the double-sided soldered semiconductor chip 4, the first insulating substrate 1, the second insulating substrate 2, and the lead frame 3, and complete the assembly, welding, and cleaning of the first insulating substrate 1, the second insulating substrate 2, the first copper sheet metal part 5, the second copper sheet metal part 6, the lead frame 3, and the resistor 7; 3) Bonding the first insulating substrate 1 and the second insulating substrate 2 to each component using bonding wires 9; 4) Package the bonded power module.
[0025] In the step 2), the first insulating substrate 1, the second insulating substrate 2, the first copper sheet metal part 5, the second copper sheet metal part 6, and the lead frame 3 are assembled by a jig to ensure the accuracy of the position of each component on the module after welding.
[0026] In the steps 1) and 2), the maximum temperature of the solder 8 is maintained between 100-400°C.
[0027] The power module designed by the present invention adopts the technology of welding and connecting the front power pole of the chip part of the insulated gate bipolar transistor and the diode with copper sheet metal instead of bonding wire, thereby increasing the contact surface of the electrical connection, which is beneficial to improving the reliability of the electrical connection of the main circuit of the power module. The presence of the thermal capacity of the copper sheet metal is beneficial to the chip part of the insulated gate bipolar transistor and the diode to resist transient thermal shock during module operation and reduce the chip junction temperature fluctuation. Therefore, the module has better reliability performance.
[0028] The specific embodiments described herein are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.
Claims
1. A double-sided welded and single-sided water-cooled IGBT power module, comprising a power module body placed on a jig, the power module body comprising a first insulating substrate (1) and a second insulating substrate (2) arranged opposite to each other, at least one lead frame (3) being arranged on one side of the first insulating substrate (1) and the second insulating substrate (2), a semiconductor chip (4) capable of double-sided weldability being welded onto both the first insulating substrate (1) and the second insulating substrate (2) via solder (8), a first copper sheet metal part (5) and a second copper sheet metal part (6) being welded onto the semiconductor chip (4) of the first insulating substrate (1) and the second insulating substrate (2) via solder (8), the first copper sheet metal part (5) and the second copper sheet metal part (6) being connected to the lead frame via bonding wires (9) and solder, respectively, the semiconductor chip comprising an insulated gate bipolar transistor and a diode capable of double-sided weldability.
2. The double-sided welded and single-sided water-cooled IGBT power module according to claim 1, characterized in that: The first insulating substrate (1) and the second insulating substrate (2) are both composed of an upper copper layer sintered into one piece, an intermediate insulating layer composed of a polymer or ceramic, and a lower copper layer.
3. The double-sided welded and single-sided water-cooled IGBT power module according to claim 1, characterized in that: The first copper sheet metal part (5) and the second copper sheet metal part (6) have a thickness of 0.1 mm to 10 mm and are made of copper, which facilitates stamping, slotting and bending.
4. The double-sided welded and single-sided water-cooled IGBT power module according to claim 1, characterized in that: The lead frame (3) is composed of a soldering pad and pins, a power terminal and a signal terminal respectively arranged on the soldering pad, and a resistor (7) is also connected to the soldering pad via solder.
5. The double-sided welded and single-sided water-cooled IGBT power module according to claim 4, characterized in that: The resistor (7) connected to the lead frame (3) includes a thermistor and a bonding resistor.
6. The double-sided welded and single-sided water-cooled IGBT power module according to claim 4, characterized in that: The material of the lead frame (3) is copper, and electroplating may or may not be performed on the copper surface, and the electroplated metal is composed of one or more of gold, silver, nickel, and tin.
7. The double-sided welded and single-sided water-cooled IGBT power module according to claim 4, characterized in that: The solder is lead-free solder paste or tin flake. The printing thickness of the lead-free solder paste is 50-500um, the weight of the solder paste at each solder joint is 0.01-50g, the thickness of the tin flake is 50-500um, and the weight of the tin flake at each solder joint is 0.01-50g.
8. A welding process for a double-sided welded and single-sided water-cooled IGBT power module according to any one of claims 1 to 7, characterized in that: The welding process comprises the following steps: 1) welding all double-sided welded semiconductor chips (4) onto a first insulating substrate (1) and a second insulating substrate (2), and cleaning them; 2) assembling the first insulating substrate (1) and the second insulating substrate (2) on a jig, adding solder (8) to corresponding positions on the double-sided soldered semiconductor chip (4), the first insulating substrate (1), the second insulating substrate (2), and the lead frame (3), and completing the assembly, soldering, and cleaning of the first insulating substrate (1), the second insulating substrate (2), the first copper sheet metal part (5), the second copper sheet metal part (6), the lead frame (3), and the resistor (7); 3) bonding the first insulating substrate (1) and the second insulating substrate (2) to each component using bonding wires (9); 4) Package the bonded power module.
9. The welding process according to claim 8, characterized in that: In the step 2), the first insulating substrate (1), the second insulating substrate (2), the first copper sheet metal part (5), the second copper sheet metal part (6), and the lead frame (3) are assembled by means of a jig to ensure the accuracy of the position of each component on the module after welding.
10. The welding process according to claim 8, characterized in that: In the steps 1) and 2), the maximum temperature of the solder (8) is maintained between 100 and 400°C.