IGBT module packaging structure and IGBT module

Abstract

The utility model relates to the technical field of semiconductor processing, and disclose an IGBT module packaging structure and IGBT module, IGBT module packaging structure includes shell body and base plate, the lower end of shell body is pasted connection through the colloid with the upper end of base plate, and the front and back of shell body all are equipped with a plurality of internal thread holes who are opened in the whole, and the inner wall thread sleeve of every internal thread hole is provided with the external thread sleeve, the inner wall fixed sleeve of external thread sleeve is provided with waterproof and breathable membrane, and the outer end fixed mounting of external thread sleeve is located the baffle of shell body outside. The utility model through shell body, base plate, internal thread hole and waterproof and breathable membrane's cooperation and cooperation, with the help of waterproof and breathable membrane realizes the air countercurrent of shell body inside and outside, effectively speeds up the heat dissipation of module inside, improves the problem that traditional closed shell heat dissipation is limited, promotes overall heat dissipation efficiency, waterproof and breathable membrane can block the invasion of external dust, water vapor into the shell body inside at the same time, avoids dust accumulation, damp leakage, guarantees the stable work of internal chip, base plate and other elements.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor processing technology, specifically to an IGBT module packaging structure and an IGBT module. Background Technology

[0002] As core power devices in power electronic equipment, IGBT modules are widely used in new energy, industrial frequency conversion, rail transportation, photovoltaic inverters, and other fields. During operation, the chips continuously generate a large amount of heat, and the heat dissipation performance directly determines the module's operating power, lifespan, and reliability. Most existing conventional IGBT module packaging structures adopt a fully enclosed shell design, with the shell and substrate sealed together using adhesive. The overall structure is a sealed cavity, and the internal components such as the IGBT chip, FRD freewheeling diode chip, and bonding wires are encased in silicone. Heat dissipation primarily relies on conduction from the bottom substrate to an external heat sink.

[0003] However, by using a one-way heat dissipation method at the bottom of the module, heat in the area above the chip cannot be quickly dissipated outwards. Internal heat tends to accumulate in the enclosed shell, resulting in a large temperature gradient and localized temperature rise inside the module. Under long-term high-temperature conditions, the silicone layer is prone to aging and cracking, the bonding wires are prone to thermal fatigue and detachment, and the thermal cycling stress of the chip increases, which seriously affects the working stability and service life of the IGBT module. At the same time, the poor air circulation inside the sealed structure makes it difficult for heat to be exchanged with the outside air after heat accumulation, further aggravating the heat dissipation problem and failing to meet the heat dissipation requirements under high power and high frequency conditions. Utility Model Content

[0004] To address the shortcomings of existing technologies, this utility model provides an IGBT module packaging structure and an IGBT module, which has the advantages of reducing damage to the IGBT module caused by high temperature, extending the service life of the IGBT module, and maintaining the airflow inside and outside the outer casing of the IGBT module, thus solving the problems mentioned in the background art.

[0005] This utility model provides the following technical solution: an IGBT module packaging structure, including an outer shell and a substrate. The lower end of the outer shell is bonded to the upper end of the substrate through an adhesive. The front and back of the outer shell are provided with a plurality of internal threaded holes. An external threaded sleeve is threaded onto the inner wall of each internal threaded hole. A waterproof and breathable membrane is fixedly fitted onto the inner wall of the external threaded sleeve. A baffle located outside the outer shell is fixedly installed at the outer end of the external threaded sleeve.

[0006] Preferably, an upper clamping plate assembly is fixedly installed on the lower end face of the outer shell, and the outer shell is movably clamped to the base plate through the upper clamping plate assembly. A plurality of first flow holes are equidistantly opened on the upper clamping plate assembly.

[0007] Preferably, a lower clamping plate assembly is fixedly installed on the upper end surface of the substrate, and the lower clamping plate assembly is movably clamped to the upper clamping plate assembly. A plurality of second flow holes are equidistantly opened on the lower clamping plate assembly.

[0008] Preferably, the upper plate assembly includes a first upper plate, a second upper plate, and a third upper plate. The first upper plate, the second upper plate, and the third upper plate are installed sequentially from the inside to the outside on the bottom surface of the outer casing. The second upper plate and the third upper plate are each provided with a plurality of first flow holes at equal intervals and through. The second upper plate and the third upper plate are both movably engaged with the lower plate assembly.

[0009] Preferably, the lower plate assembly includes a first lower plate, a second lower plate, and a third lower plate, which are installed sequentially from the inside to the outside on the upper surface of the substrate. The second lower plate has a plurality of second flow holes that are equidistant and penetrate through it.

[0010] Preferably, the first lower plate is movably inserted between the first upper plate and the second upper plate, the second lower plate is movably engaged between the second lower plate and the second upper plate and the third upper plate, and the third lower plate is movably engaged outside the third upper plate. The first upper plate, the first lower plate, the second upper plate, the second lower plate, the third upper plate, and the third lower plate are sequentially and alternately engaged from the inside to the outside.

[0011] An IGBT module, using the aforementioned IGBT module packaging structure, includes a substrate, an FRD chip, an IGBT chip, and a silicone layer within a packaging space formed between a housing and a substrate. Both the FRD chip and the IGBT chip are fixedly connected with bonding wires. The silicone layer fills the packaging space and completely covers the FRD chip, IGBT chip, and bonding wires. Both the FRD chip and the IGBT chip are provided with top and bottom electrodes. The IGBT chip has two top electrodes; one top electrode of the IGBT chip is configured as the emitter, and the other top electrode is configured as... The substrate is provided with a first connection terminal and a second connection terminal, which are respectively connected to the FRD chip and the IGBT chip via bonding leads. The collector of the IGBT chip is electrically connected to the bottom electrode of the FRD chip. The emitter is connected to the top electrode of the FRD chip via a bonding lead to the first connection terminal. The first connection terminal and the bonding lead are used to realize the electrical connection between the emitter and the top electrode of the FRD chip. The gate is connected to the second connection terminal via a bonding lead to realize the electrical connection between the gate and the second connection terminal.

[0012] Preferably, the packaging space is further provided with a busbar electrode, and the busbar electrode passes through it. Each electrode in the busbar electrode is respectively connected to a corresponding lead terminal. The busbar electrode is provided with electrode lines connecting each electrode, and some of the electrode lines passing through the busbar electrode are laid in the corresponding guide groove and connected to the corresponding lead terminal on the outer casing through the guide groove.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] 1. This utility model achieves air convection between the outer shell, substrate, internal threaded hole and waterproof and breathable membrane through the coordinated cooperation of the outer shell and the substrate. This effectively accelerates the dissipation of heat inside the module, improves the problem of limited heat dissipation in traditional closed shells, and enhances the overall heat dissipation efficiency. At the same time, the waterproof and breathable membrane can prevent external dust and moisture from entering the shell, avoid dust accumulation, moisture and leakage, and ensure the stable operation of internal components such as chips and substrates.

[0015] 2. This utility model utilizes the cooperation between the outer shell, the internal threaded hole, the external threaded sleeve, and the waterproof and breathable membrane. By employing a detachable connection method where the internal threaded hole and the external threaded sleeve are connected by a threaded sleeve, the external threaded sleeve can be quickly disassembled and assembled. This facilitates the later inspection and replacement of the waterproof and breathable membrane, effectively solving the problem of inconvenient disassembly and maintenance of the breathable structure. At the same time, it ensures the breathable heat dissipation and dustproof and moisture-proof performance of the module shell, thereby ensuring the long-term stable operation of the IGBT module. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model;

[0017] Figure 2 This is a schematic diagram of the rear side of the baffle of this utility model;

[0018] Figure 3 This is a top view of the outer shell of this utility model;

[0019] Figure 4 This is a schematic diagram of the internal threaded hole of this utility model;

[0020] Figure 5 This is a schematic diagram of the assembled IGBT module of this utility model;

[0021] Figure 6 This is a bottom view of the upper card plate assembly of this utility model;

[0022] Figure 7 This utility model Figure 6 An enlarged view of point A;

[0023] Figure 8 This is a top view of the lower card plate assembly of this utility model;

[0024] Figure 9 This utility model Figure 8 An enlarged schematic diagram of point B.

[0025] In the diagram: 1. Outer shell; 2. Substrate; 3. Lead terminal; 4. Backing plate; 5. FRD chip; 6. IGBT chip; 8. Bonding lead; 901. Emitter; 902. Gate; 10. First connection terminal; 11. Second connection terminal; 12. Busbar electrode; 14. Internal threaded hole; 15. External threaded sleeve; 16. Waterproof and breathable membrane; 17. Baffle; 18. Upper clamping plate assembly; 181. First upper clamping plate; 182. Second upper clamping plate; 183. Third upper clamping plate; 19. First flow hole; 20. Lower clamping plate assembly; 201. First lower clamping plate; 202. Second lower clamping plate; 203. Third lower clamping plate; 21. Second flow hole. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] Please see Figure 1 , Figure 2 and Figure 3 An IGBT module packaging structure includes a housing 1 and a substrate 2. The IGBT module uses this packaging structure to achieve stable packaging and operation of the power device.

[0028] Connection between outer shell 1 and substrate 2: outer shell 1 is integrally injection molded from insulating resin material, and has a square cavity structure. Its lower end face is bonded to the upper end face of substrate 2 through high temperature resistant insulating adhesive. The adhesive is made of high temperature resistant silicone to ensure the sealing and stability of the connection, while avoiding aging and falling off of the adhesive under high temperature environment.

[0029] Please see Figure 4 , Figure 6 and Figure 7The outer casing 1 has several internally threaded holes 14 on both its front and back sides. Each internally threaded hole 14 has a matching internal thread on its inner wall, which matches the external thread of the externally threaded sleeve 15, achieving a threaded connection. The externally threaded sleeve 15 is made of stainless steel, and its inner wall is fixed with a waterproof and breathable membrane 16 using a high-temperature adhesive. The waterproof and breathable membrane 16 is made of polytetrafluoroethylene (PTFE) and has breathable, waterproof, and dustproof functions, allowing airflow while blocking moisture and dust. An integrally formed baffle 17 is formed at the outer end of the externally threaded sleeve 15. The diameter of the baffle 17 is larger than the diameter of the internally threaded holes 14, used to limit the screw-in depth of the externally threaded sleeve 15.

[0030] Cardboard assembly structure: An upper cardboard assembly 18 is integrally formed on the lower end face of the outer shell 1. The upper cardboard assembly 18 includes a first upper cardboard 181, a second upper cardboard 182, and a third upper cardboard 183, all of which are annular plate structures. They are vertically fixed to the lower bottom surface of the outer shell 1 from the inside out, and the three are concentrically arranged. Among them, the second upper cardboard 182 and the third upper cardboard 183 are each provided with a plurality of first flow holes 19 at equal intervals. The first flow holes 19 are circular and are used to allow air circulation between the outer shell 1 and the substrate 2 to assist in heat dissipation.

[0031] Please see Figure 9 , Figure 8 and Figure 2 The substrate 2 is made of copper heat dissipation substrate, and a lower retaining plate assembly 20 is integrally formed on its upper end surface. The lower retaining plate assembly 20 is adapted to the upper retaining plate assembly 18 and includes a first lower retaining plate 201, a second lower retaining plate 202, and a third lower retaining plate 203. The three are also ring-shaped plate structures, which are vertically fixed to the upper end surface of the substrate 2 from the inside to the outside, and correspond one-to-one with the three retaining plates of the upper retaining plate assembly 18. A number of second flow holes 21 are equally spaced through the second lower retaining plate 202. The second flow holes 21 have the same size and corresponding position as the first flow holes 19, further improving the air circulation efficiency.

[0032] The upper card plate assembly 18 and the lower card plate assembly 20 are connected by staggered insertion: the first lower card plate 201 is movably inserted between the first upper card plate 181 and the second upper card plate 182, the second lower card plate 202 is movably inserted between the second upper card plate 182 and the third upper card plate 183, and the third lower card plate 203 is movably snapped onto the outside of the third upper card plate 183, so that the first upper card plate 181, the first lower card plate 201, the second upper card plate 182, the second lower card plate 202, the third upper card plate 183 and the third lower card plate 203 are arranged alternately from the inside to the outside, which not only realizes the movable snapping of the outer shell 1 and the base plate 2, improving the connection stability, but also forms an upper and lower convection channel through the first flow hole 19 and the second flow hole 21 to assist in heat dissipation.

[0033] Please see Figure 5 and Figure 1 An IGBT module has a closed encapsulation space formed between the housing 1 and the substrate 2. The encapsulation space is provided with a liner 4, an FRD chip 5, an IGBT chip 6 and a silicone layer. The liner 4 is made of a ceramic copper-clad substrate and is fixedly installed on the upper surface of the substrate 2 to support the FRD chip 5 and the IGBT chip 6.

[0034] Both the FRD chip 5 and the IGBT chip 6 are fixedly soldered onto the substrate 4. Both are provided with top electrodes and bottom electrodes. The IGBT chip 6 is provided with two top electrodes, namely the emitter 901 and the gate 902. The collector of the IGBT chip 6 is electrically connected to the bottom electrode of the FRD chip 5 through a metal conductive layer.

[0035] Both the FRD chip 5 and the IGBT chip 6 are fixedly connected by bonding wires 8 using a bonding process. The bonding wires 8 are made of aluminum wire. The substrate 4 is fixedly mounted with a first connection terminal 10 and a second connection terminal 11. The first connection terminal 10 is connected to the top electrode of the FRD chip 5 and the emitter 901 of the IGBT chip 6 through the bonding wires 8, respectively, to realize the electrical connection between the two. The second connection terminal 11 is connected to the gate 902 of the IGBT chip 6 through the bonding wires 8 to realize the transmission of the gate signal.

[0036] The encapsulation space is filled with a silicone layer. The silicone layer is made of high-temperature resistant insulating silicone. After filling, it completely covers the bottom of the FRD chip 5, IGBT chip 6, bonding wire 8, substrate 4, and the first connection terminal 10 and the second connection terminal 11, which serves to provide insulation, moisture protection, and buffering, and prevent the internal components from being affected by external interference or mechanical damage.

[0037] The packaged space also includes busbar electrodes 12, which pass through pre-drilled holes in the housing 1. Each electrode in the busbar electrodes 12 is connected to a corresponding lead terminal 3, which is fixedly mounted on the side of the housing 1 to connect the IGBT module to an external circuit. Inside the busbar electrodes 12, electrode wires connecting each electrode are arranged. A portion of the electrode wire passing through the through-hole is laid in a pre-drilled guide groove inside the housing 1. The guide groove limits and guides the electrode wires, ensuring precise connection to the corresponding lead terminal 3 on the housing 1 and preventing short circuits caused by tangled electrode wires.

[0038] Working principle: Assembly process:

[0039] First, the FRD chip 5 and IGBT chip 6 are soldered onto the substrate 4, and the chips are connected to the first connection terminal 10 and the second connection terminal 11 through the bonding wire 8 to complete the assembly of the internal components.

[0040] Then, the liner 4 is fixedly installed on the upper surface of the substrate 2, the busbar electrode 12 is installed in the packaging space, the electrode wire passes through the through hole and is laid in the guide groove, and is connected to the lead terminal 3.

[0041] Subsequently, a silicone layer is filled into the encapsulation space to ensure that the silicone layer completely covers all internal components. Then, the outer shell 1 is interlocked with the lower clamping assembly 20 of the substrate 2 via the upper clamping assembly 18, and the outer shell 1 and the substrate 2 are glued and fixed together.

[0042] Finally, the waterproof and breathable membrane 16 is fixedly fitted onto the inner wall of the external threaded sleeve 15, and then the external threaded sleeve 15 is screwed into the internal threaded hole 14 on the outer shell 1 until the baffle 17 fits against the surface of the outer shell 1, thus completing the assembly of the entire encapsulation structure and the IGBT module.

[0043] How to use:

[0044] First, the IGBT module is fixedly mounted on the external heat sink using the substrate 2, ensuring that the substrate 2 and the heat sink are in close contact to facilitate heat dissipation from the bottom. The lead terminal 3 is then connected to the external circuit to enable the IGBT module to be powered on.

[0045] Then, during the operation of the IGBT module, the IGBT chip 6 and the FRD chip 5 generate a large amount of heat. Part of the heat is conducted to the substrate 2 through the liner 4, and then conducted to the external heat sink for dissipation. Another part of the heat causes the air in the packaging space to expand due to heat. It forms convection with the outside cold air through the internal threaded hole 14 on the outer shell 1 and the waterproof and breathable membrane 16 in the external threaded sleeve 15. At the same time, the first flow hole 19 of the upper plate assembly 18 and the second flow hole 21 of the lower plate assembly 20 form an upper and lower convection channel, which accelerates the air flow in the packaging space, further improves the heat dissipation efficiency, realizes bidirectional heat dissipation, and avoids the accumulation of heat in the packaging space.

[0046] Subsequently, the waterproof and breathable membrane 16, while enabling air convection, can effectively block external dust and moisture from entering the encapsulation space, preventing dust accumulation, moisture leakage, and other issues in internal components such as chips and bonding wires 8, thus ensuring the stable operation of the IGBT module.

[0047] Finally, if the waterproof and breathable membrane 16 becomes clogged or ages after long-term use, the external threaded sleeve 15 can be rotated to remove it from the internal threaded hole 14. After replacing the waterproof and breathable membrane 16, the external threaded sleeve 15 can be screwed back into the internal threaded hole 14 to complete the maintenance and replacement. The operation is convenient and does not require disassembling the entire IGBT module, thus reducing maintenance costs.

[0048] In addition, the staggered snap-fit ​​structure between the outer casing 1 and the substrate 2 not only improves the stability of the connection, but also buffers the vibration when the module is subjected to vibration through the cooperation between the snap-fit ​​plates, avoiding damage to the internal components and further extending the service life of the IGBT module.

[0049] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Additionally, in the accompanying drawings of this utility model, the fill patterns are merely for distinguishing layers and do not constitute any other limitation.

[0050] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An IGBT module packaging structure, comprising a housing (1) and a substrate (2), wherein the lower end of the housing (1) is bonded to the upper end of the substrate (2) by an adhesive, characterized in that: The outer shell (1) has several internal threaded holes (14) through its front and back sides. Each internal threaded hole (14) has an external threaded sleeve (15) threaded onto its inner wall. The inner wall of the external threaded sleeve (15) is fixedly fitted with a waterproof and breathable membrane (16). The outer end of the external threaded sleeve (15) is fixedly installed with a baffle (17) located outside the outer shell (1).

2. The IGBT module packaging structure according to claim 1, characterized in that: The lower end face of the outer shell (1) is fixedly installed with an upper clamping plate assembly (18). The outer shell (1) is movably clamped to the base plate (2) through the upper clamping plate assembly (18). The upper clamping plate assembly (18) has several first flow holes (19) that are equidistantly opened through it.

3. The IGBT module packaging structure according to claim 2, characterized in that: The upper end face of the substrate (2) is fixedly installed with a lower clamping plate assembly (20), which is movably clamped to the upper clamping plate assembly (18). The lower clamping plate assembly (20) has several second flow holes (21) that are equidistantly opened through it.

4. The IGBT module packaging structure according to claim 3, characterized in that: The upper plate assembly (18) includes a first upper plate (181), a second upper plate (182) and a third upper plate (183). The first upper plate (181), the second upper plate (182) and the third upper plate (183) are installed sequentially from the inside to the outside on the bottom surface of the outer shell (1). The second upper plate (182) and the third upper plate (183) are each provided with a plurality of first flow holes (19) at equal intervals. The second upper plate (182) and the third upper plate (183) are both movably engaged with the lower plate assembly (20).

5. The IGBT module packaging structure according to claim 4, characterized in that: The lower plate assembly (20) includes a first lower plate (201), a second lower plate (202) and a third lower plate (203). The first lower plate (201), the second lower plate (202) and the third lower plate (203) are installed sequentially from the inside to the outside on the upper surface of the substrate (2). The second lower plate (202) has a plurality of second flow holes (21) that are equidistantly opened through it.

6. The IGBT module packaging structure according to claim 5, characterized in that: The first lower plate (201) is movably inserted between the first upper plate (181) and the second upper plate (182), the second lower plate (202) is movably inserted between the second upper plate (182) and the third upper plate (183), and the third lower plate (203) is movably snapped onto the outside of the third upper plate (183). The first upper plate (181), the first lower plate (201), the second upper plate (182), the second lower plate (202), the third upper plate (183) and the third lower plate (203) are sequentially and alternately inserted from the inside to the outside.

7. An IGBT module, using the IGBT module packaging structure according to any one of claims 1-6, characterized in that: The package includes a liner (4), an FRD chip (5), an IGBT chip (6), and a silicone layer disposed in the encapsulation space between the outer casing (1) and the substrate (2). The FRD chip (5) and the IGBT chip (6) are fixedly connected with bonding wires (8). The silicone layer fills the encapsulation space and completely covers the FRD chip (5), the IGBT chip (6), and the bonding wires (8).

8. An IGBT module according to claim 7, characterized in that: Both the FRD chip (5) and the IGBT chip (6) are provided with top electrodes and bottom electrodes. The IGBT chip (6) is provided with two top electrodes, namely the emitter (901) and the gate (902).

9. An IGBT module according to claim 8, characterized in that: The substrate (4) is provided with a first connection terminal (10) and a second connection terminal (11). The first connection terminal (10) and the second connection terminal (11) are respectively connected to the FRD chip (5) and the IGBT chip (6) through bonding leads (8). The collector of the IGBT chip (6) is electrically connected to the bottom electrode of the FRD chip (5). The emitter (901) is connected to the top electrode of the FRD chip (5) through bonding leads (8) to the first connection terminal (10). The gate (902) is connected to the second connection terminal (11) through bonding leads (8).

10. An IGBT module according to claim 7, characterized in that: The encapsulation space is also provided with a busbar electrode (12), the busbar electrode (12) is connected to a lead terminal (3), the busbar electrode (12) is provided with an electrode wire, and the electrode wire is connected to the corresponding lead terminal (3) on the outer shell (1) through a guide groove.

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