Press-pack semiconductor power module

Abstract

The present application relates to the technical field of semiconductor, and particularly provides a crimping type power semiconductor module. The crimping type power semiconductor module comprises a pipe base, an inner part of the pipe base having a containing cavity; a pipe cover located on the pipe base and in sealed connection with the pipe base; the pipe cover comprising a first main electrode; a chip assembly and an explosion-proof positioning frame located in the containing cavity, the chip assembly and the first main electrode being oppositely and in contact connection; the explosion-proof positioning frame surrounding the sidewall of the chip assembly; wherein a side surface of the first main electrode facing the chip assembly has a discharge channel extending to the edge of the first main electrode; and a side surface of the explosion-proof positioning frame facing away from the pipe cover has an opening extending from the inner sidewall of the explosion-proof positioning frame to the outer sidewall of the explosion-proof positioning frame.

Description

Technical Field

[0001] This invention relates to the field of semiconductor technology, and in particular to a press-fit semiconductor power module. Background Technology

[0002] In power electronic systems, especially in grid-level applications (such as high-voltage direct current transmission (HVDC) and flexible alternating current transmission systems (FACTS)), flexible press-fit insulated gate bipolar transistor (IGBT) modules are often selected as core power switching devices. These devices typically need to meet key requirements such as high blocking voltage, large current capacity, high reliability, and long service life. However, flexible press-fit IGBT modules have weak current-carrying capacity after long-term failure, and their resistance to salt spray corrosion and moisture penetration is relatively insufficient in harsh operating environments such as offshore wind power transmission, affecting their long-term stable operation in coastal or offshore wind power scenarios. Therefore, the technical advantages of rigid press-fit IGBT modules are becoming increasingly apparent. In rigid press-fit IGBT modules, the chip and molybdenum sheet are sintered together on both sides and then rigidly connected to the electrodes, which enables them to maintain better current conduction characteristics in the event of failure. At the same time, their packaging form usually has better airtightness and environmental isolation effect, thereby significantly improving reliability under harsh conditions such as high humidity and high salt spray, making them more suitable for power grid equipment with extremely high requirements for durability and environmental adaptability.

[0003] In related technologies, with the continuous increase in current levels, especially those reaching 5000A and above, the number of parallel-connected chips inside rigid press-fit IGBT modules also increases. During long-term power cycling, when a chip fails due to extreme electrical stress (such as a short circuit), it releases enormous energy instantaneously. However, traditional press-fit IGBT modules struggle to effectively confine and dissipate this energy, easily leading to catastrophic "module explosion" failures such as casing rupture and flying debris, posing a serious threat to the safe and stable operation of the entire power electronic system.

[0004] Therefore, there is an urgent need to provide a solution to ensure that the press-fit IGBT module can maintain its structural integrity even under extreme failure modes. Summary of the Invention

[0005] The purpose of this invention is to provide at least one press-fit semiconductor power module, which can at least improve the reliability of the press-fit semiconductor power module.

[0006] To address the aforementioned technical problems, the present invention provides a press-fit power semiconductor module, comprising: a socket having an internal cavity; a cap located on the socket and sealed to it; the cap including a first main electrode; a chip assembly and an explosion-proof positioning frame located within the cavity, the chip assembly and the first main electrode being opposite to and in contact with each other; the explosion-proof positioning frame surrounding the sidewall of the chip assembly; wherein the surface of the first main electrode facing the chip assembly has a venting channel extending to the edge of the first main electrode; the surface of the explosion-proof positioning frame opposite to the cap has an opening extending from the inner sidewall of the explosion-proof positioning frame to the outer sidewall of the explosion-proof positioning frame.

[0007] The semiconductor power module provided by this invention, after the tube cover and tube seat are sealed together, the chip assembly and the first main electrode are positioned opposite each other and in contact, and an explosion-proof positioning frame surrounds the side wall of the chip assembly. When the chip assembly generates impact energy of high-temperature and high-pressure gas instantaneously due to a fault such as a short circuit, on the one hand, because the surface of the first main electrode facing the chip assembly has a venting channel that extends to the edge of the first main electrode, the high-temperature and high-pressure gas can be led out to the edge of the first main electrode through the venting channel, effectively preventing the high-temperature and high-pressure gas from impacting the main electrical contact interface of the first main electrode and preventing secondary short circuits or functional failures; on the other hand, the surface of the explosion-proof positioning frame away from the tube cover has a self-explosion-proof positioning function. The inner wall of the frame extends to the opening on the outer wall of the explosion-proof positioning frame. High-temperature and high-pressure gases can be released through the opening, achieving deceleration and cooling of the high-temperature and high-pressure gases. The explosion-proof positioning frame is integrally molded or assembled from high-strength insulating composite material, possessing excellent mechanical strength and electrical insulation properties. It can directly absorb and block most of the impact energy generated by the high-temperature and high-pressure gases released to the edge of the first main electrode and to the opening, effectively protecting the assembly fixtures and caps of the socket and chip components from damage. This prevents fragments from flying due to the breakage of the socket and cap, maintains the integrity of the press-fit power semiconductor module, and improves the reliability and safety of the press-fit power semiconductor module.

[0008] Furthermore, the discharge channel includes a central groove, an annular groove, and a connecting groove. The central groove is located at the center of the first main electrode, the annular groove surrounds the central groove, and the connecting groove connects the central groove and the annular groove, extending from the annular groove to the edge of the first main electrode. During operation, the temperature is highest in the central region of the press-fit power semiconductor module. The central groove serves as the discharge concentration point, and the connecting groove evenly guides the impact energy of the high-temperature, high-pressure gas to the annular groove, which then disperses it to the edge of the first main electrode. This design avoids localized overload of the high-temperature, high-pressure gas, ensuring uniform dispersion of the gas from the center to the edge, thus improving the uniformity and efficiency of impact energy discharge.

[0009] Furthermore, there are multiple annular grooves, including a first annular groove to an Nth annular groove; N is an integer greater than or equal to 2; the first annular groove surrounds the central groove, and the nth annular groove surrounds the (n-1)th annular groove, where n is an integer greater than or equal to 2 and less than or equal to N; the connecting groove connects the central groove and the first annular groove, connects the nth annular groove and the (n-1)th annular groove, and connects the Nth annular groove to the edge of the first main electrode. The impact energy of the high-temperature and high-pressure gas can be released layer by layer from the central groove through the multi-level annular grooves, realizing a mechanism of graded release path, guiding the destructive energy to a controllable path for release, achieving rapid energy dispersion and dissipation, and further improving the uniformity and efficiency of impact energy release.

[0010] Furthermore, at least two of the connecting grooves connecting the central groove and the first annular groove, the connecting groove connecting the nth annular groove and the (n-1)th annular groove, and the connecting groove connecting the Nth annular groove to the edge of the first main electrode are arranged opposite to each other or staggered. Oppositely arranged connecting grooves can form a more efficient discharge path, allowing the high-temperature, high-pressure impact energy generated by the chip assembly to dissipate quickly, reducing discharge resistance, avoiding localized high-temperature, high-pressure gas overload, and enhancing the uniformity and efficiency of impact energy discharge. In addition, oppositely arranged connecting grooves are often easier to process and assemble, which helps simplify the manufacturing process.

[0011] Furthermore, there are multiple openings, including a first opening and a second opening, wherein the size of the first opening is greater than or equal to the size of the second opening. This design balances the requirements of high efficiency in dissipating the impact energy of high-temperature and high-pressure gases with the high mechanical strength of the explosion-proof positioning frame, thereby improving the reliability and safety of the press-fit semiconductor power module.

[0012] In addition, the tube cover also includes: a first flange, which surrounds and is connected to the first main electrode in the circumferential direction of the first main electrode; the press-fit power semiconductor module also includes: a first thinning region, which includes a first through hole penetrating the first flange along its thickness direction and a first gasket located on the surface of the first through hole away from the receiving cavity, the thickness of the first gasket being less than the thickness of the first flange. Because the first gasket is thinner, impact energy is preferentially concentrated in the area of ​​the first gasket. The first thinning region, as a preset weak point, forms a controllable vent. When extreme overheating occurs inside the press-fit power semiconductor module, causing the venting channel to become unbearable, the impact energy of the high-temperature, high-pressure gas is forced open through the first thinning region designed with the first flange in a specific orientation. Its burst pressure is precisely calibrated, achieving an active directional venting function, guiding the destructive energy to a controllable path for release, achieving rapid energy dispersion and dissipation, and actively isolating the fault point of the chip component, ensuring the safety goal of "failure not propagating" for the press-fit power semiconductor module is achieved.

[0013] Additionally, the tube socket includes a second main electrode, a second flange, and an insulating shell. The second main electrode and the first main electrode are disposed opposite to each other. The second flange surrounds the second main electrode in the circumferential direction and is connected to the second main electrode. The insulating shell is located on the second main electrode and surrounds the receiving cavity. One end of the insulating shell is connected to the second flange, and the other end is connected to the tube cap. The press-fit power semiconductor module further includes a second thinning region. The second thinning region includes a second through hole penetrating the second flange along the thickness direction of the second flange and a second gasket located on the surface of the second through hole facing away from the receiving cavity. The thickness of the second gasket is less than the thickness of the second flange. Because the second gasket is thinner, the impact energy is preferentially concentrated in the area of ​​the second gasket. The second thinning area, as a pre-set weak point, forms a controllable vent. When the opening on the surface of the explosion-proof positioning frame, which serves as the first physical barrier on the side of the chip assembly facing the second main electrode, cannot withstand the impact energy of the high-temperature and high-pressure gas generated due to extreme overheating, the impact energy is pushed open through the second thinning area designed and oriented by the second flange. Its burst pressure is precisely calibrated to achieve an active directional venting function, guiding the destructive energy to a controllable path for release, achieving rapid energy dispersion and dissipation, and actively isolating the fault point of the chip assembly. This significantly improves the overall structural safety of the chip assembly under fault conditions, ensuring that the impact energy is "guided and isolated" rather than completely "hard-resisted" by the explosion pressure, avoiding secondary disasters. This ensures that the press-fit power semiconductor module can still maintain structural integrity in extreme failure modes, greatly improving the reliability and safety of the press-fit power semiconductor module.

[0014] Additionally, it includes: a circuit board located within the receiving cavity, the circuit board being situated between the chip assembly and the second main electrode; the circuit board having multiple third through holes; the surface of the second main electrode having multiple bosses, the bosses passing through the third through holes and electrically connected to the chip assembly; wherein, gaps exist between the multiple bosses. The impact energy of high-temperature, high-pressure gas instantaneously generated by a short circuit or other fault in the chip assembly can be released through these gaps, achieving deceleration and cooling of the high-temperature, high-pressure gas.

[0015] Furthermore, the chip assembly includes multiple chip units connected in parallel; each chip unit includes a chip body, a first compensation plate, and a second compensation plate. The first compensation plate and the second compensation plate are respectively located on two opposing surfaces of the chip body, and the first compensation plate is electrically connected to a first sub-electrode and a first main electrode of the chip body, respectively. The second compensation plate is electrically connected to a second sub-electrode and a second main electrode of the chip body, respectively. The chip assembly includes a central region, a transition region surrounding the central region, and an edge region surrounding the transition region. In each chip unit, the first compensation plate and / or the second compensation plate located in the central region have a first material, the first compensation plate and / or the second compensation plate located in the transition region have a second material, and the first compensation plate and / or the second compensation plate located in the edge region have a third material. The thermal conductivity of the first material is greater than that of the second material, and the thermal conductivity of the second material is greater than that of the third material. The hardness of the first material is less than that of the second material, and the hardness of the second material is less than that of the third material. The gradient design described above achieves synergistic optimization of thermal-mechanical coupling performance, improving heat dissipation efficiency while ensuring uniform distribution of compressive stress at each contact interface and temperature uniformity of the multi-chip units when they are connected in parallel.

[0016] In addition, the first material is a molybdenum-copper alloy, wherein the ratio of the number of molybdenum atoms to the number of copper atoms in the first material is 2 to 3; the second material is a molybdenum-copper alloy, wherein the ratio of the number of molybdenum atoms to the number of copper atoms in the second material is 4 to 6; and the third material is molybdenum. Attached Figure Description

[0017] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0018] Figure 1 An exploded view of a press-fit semiconductor power module provided in an embodiment of the present invention; Figure 2 This is a top view of the tube cover in the press-fit semiconductor power module provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the explosion-proof positioning frame in a press-fit semiconductor power module provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the connection between the tube cover and the tube socket in a press-fit semiconductor power module provided in an embodiment of the present invention; Figure 5A cross-sectional view of the tube cover in the press-fit semiconductor power module provided in an embodiment of the present invention; Figure 6 for Figure 5 A magnified view of a portion of region A in the middle; Figure 7 for Figure 4 A magnified view of a portion of region B in the middle; Figure 8 This is a schematic diagram of the chip unit structure in the press-fit semiconductor power module provided in an embodiment of the present invention; Figure 9 This is an exploded view of a chip unit in a press-fit semiconductor power module provided in an embodiment of the present invention; Figure 10 This is a schematic diagram showing the distribution of chip components in a press-fit semiconductor power module provided in an embodiment of the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to enable the reader to better understand the present invention. However, the technical solutions claimed in the present invention can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0020] Reference Figures 1 to 4 This invention provides a press-fit power semiconductor module, comprising: a socket 5 having an internal cavity; and a cap 1 located on the socket 5 and sealed to it (see reference). Figure 4 ); The cap 1 includes a first main electrode 11 (see Figure 1 The chip assembly 3 and the explosion-proof positioning frame 2 are located within the receiving cavity. The chip assembly 3 and the first main electrode 11 are arranged opposite to and in contact with each other. The explosion-proof positioning frame 2 surrounds the side wall of the chip assembly 3. The surface of the first main electrode 11 facing the chip assembly 3 has a venting channel 7, and the venting channel 7 extends to the edge of the first main electrode 11 (see [reference]). Figure 2 The explosion-proof positioning frame 2 has an opening 8 on the side surface opposite to the pipe cover 1, extending from the inner wall of the explosion-proof positioning frame 2 to the outer wall of the explosion-proof positioning frame 2 (see...). Figure 3 ).

[0021] In this embodiment, after the tube cap 1 and tube seat 5 are sealed together, the chip assembly 3 and the first main electrode 11 are positioned opposite each other and in contact. The explosion-proof positioning frame 2 surrounds the side wall of the chip assembly 3. When the chip assembly 3 generates high-temperature and high-pressure gas impact energy due to a short circuit or other fault, on the one hand, since the surface of the first main electrode 11 facing the chip assembly 3 has a venting channel 7 that extends to the edge of the first main electrode 11, the high-temperature and high-pressure gas can be led out to the edge of the first main electrode through the venting channel, effectively preventing the high-temperature and high-pressure gas from impacting the main electrical contact interface of the first main electrode 11 and preventing secondary short circuits or functional failures; on the other hand, the surface of the explosion-proof positioning frame 2 facing away from the tube cap 1 has a self-explosion-proof positioning frame. The inner wall of 2 extends to the opening 8 on the outer wall of the explosion-proof positioning frame 2. High-temperature and high-pressure gas can be released through the opening 8 to achieve deceleration and cooling of the high-temperature and high-pressure gas. The explosion-proof positioning frame 2 is integrally formed or assembled from high-strength insulating composite material, which has excellent mechanical strength and electrical insulation properties. It can directly absorb and block most of the impact energy generated by the high-temperature and high-pressure gas released to the edge of the first main electrode 11 and to the opening 8. It effectively protects the assembly tooling of the tube seat 5, the chip assembly 3 and the tube cover 1 from damage, thereby preventing the fragments from splashing due to the breakage of the tube seat 5 and the tube cover 1, maintaining the integrity of the press-fit power semiconductor module and improving the reliability and safety of the press-fit semiconductor power module.

[0022] After the chip assembly 3 and the tube cover 1 are connected, the venting channel 7 on the surface of the first main electrode 11 forms a gas expansion chamber between the chip assembly 3 and the chip assembly 3, which vents the high temperature and high pressure gas generated by the failure of the chip assembly 3.

[0023] In this embodiment, we continue to refer to Figure 2 The discharge channel 7 includes a central groove 71, an annular groove 72, and a connecting groove 73. The central groove 71 is located at the center of the first main electrode 11, the annular groove 72 surrounds the central groove 71, and the connecting groove 73 connects the central groove 71 and the annular groove 72, extending from the annular groove 72 to the edge of the first main electrode 11. The main discharge path of the high-temperature and high-pressure gas is as follows: from the central groove 71 through the connecting groove 73 connecting the central groove 71 and the annular groove 72 to the annular groove 72, and from the annular groove 72 through the connecting groove 73 connecting the annular groove 72 to the edge of the first main electrode 11, the gas is discharged to the edge of the first main electrode 11. During operation, the temperature is highest in the central region of the chip assembly 3 of the press-fit power semiconductor module. The central groove 71 serves as the discharge concentration point, and the impact energy of the high-temperature and high-pressure gas is uniformly guided to the annular groove 72 through the connecting groove 73, and then dispersed to the edge of the first main electrode 11 by the annular groove 72. This design can avoid local overload of high-temperature and high-pressure gas, and make the high-temperature and high-pressure gas evenly dispersed from the center to the edge, improving the uniformity and efficiency of impact energy discharge.

[0024] It is understandable that the central groove 71 is the intermediate gas expansion chamber formed between the chip assembly 3 and the tube cap 1 after they are connected in contact; the annular groove 72 is the annular gas expansion chamber formed between the chip assembly 3 and the tube cap 1 after they are connected in contact; and the connecting groove 73 is the main venting chamber formed between the chip assembly 3 and the tube cap after they are connected in contact.

[0025] In other embodiments, the discharge channel can be other forms of groove structure, such as a strip groove, wherein the strip groove extends to the edge of the first main electrode.

[0026] Further, in one embodiment, there are multiple annular grooves 72, including a first annular groove to an Nth annular groove; N is an integer greater than or equal to 2; the first annular groove is arranged around the central groove, and the nth annular groove is arranged around the (n-1)th annular groove, where n is an integer greater than or equal to 2 and less than or equal to N; the connecting groove 73 connects the central groove 71 and the first annular groove, connects the nth annular groove and the (n-1)th annular groove, and connects the Nth annular groove to the edge of the first main electrode 11. That is, multiple annular grooves 72 are arranged in concentric rings from the center of the first main electrode 11 to the edge of the first main electrode 11 at intervals. During operation, the central groove of the press-fit power semiconductor module serves as the concentration point for venting. The impact energy of the high-temperature and high-pressure gas is sequentially transferred to the first annular groove, the second annular groove, and so on to the Nth annular groove through the connecting groove, and then transferred to the edge of the first main electrode 11. The impact energy of the high-temperature and high-pressure gas can be released layer by layer from the central groove 71 through the multi-level annular grooves 72, realizing the mechanism of graded venting path, guiding the destructive energy to a controllable path for release, realizing rapid energy dispersion and dissipation, and further improving the uniformity and efficiency of impact energy venting.

[0027] In this embodiment, N is an integer equal to 2 as an example. See also... Figure 2 The plurality of annular grooves 72 include a first annular groove 721 and a second annular groove 722. The first annular groove 721 is arranged around the central groove 71, and the second annular groove 722 is arranged around the first annular groove 721. The connecting groove 73 connects the central groove 71 and the first annular groove 721, connects the second annular groove 722 and the first annular groove 721, and connects the second annular groove 722 to the edge of the first main electrode 11.

[0028] In other embodiments, the number of annular grooves is not limited and can be reasonably set according to the spatial dimensions of the first main electrode.

[0029] In one embodiment, at least two of the connecting grooves connecting the central groove 71 and the first annular groove, the connecting grooves connecting the nth annular groove and the (n-1)th annular groove, and the connecting grooves connecting the Nth annular groove to the edge of the first main electrode are arranged opposite to each other or staggered.

[0030] Continue to refer to Figure 2 In this embodiment, the connecting groove 73 connecting the central groove 71 and the first annular groove 721, the connecting groove 73 connecting the second annular groove 722 and the first annular groove 721, and the connecting groove 73 connecting the second annular groove 722 to the edge of the first main electrode 11 are all arranged oppositely as an illustration. The oppositely arranged connecting grooves 73 can form a more effective discharge path, and the impact energy of the high temperature and high pressure generated by the chip assembly 3 can be quickly dissipated, reducing discharge resistance, avoiding local high temperature and high pressure gas overload, and enhancing the uniformity and efficiency of impact energy discharge. In addition, the oppositely arranged connecting grooves 73 are often easier to process and assemble, which helps to simplify the manufacturing process.

[0031] In one embodiment, in conjunction with reference Figure 1 , Figure 2 , Figure 5 and Figure 6 The tube cap 1 further includes: a first flange 12, which surrounds and is connected to the first main electrode 11 in the circumferential direction; the press-fit power semiconductor module further includes: a first thinning region 13, which includes a first through hole 131 penetrating the first flange 12 along the thickness direction of the first flange 12 and a first gasket 132 located on the surface of the first through hole 131 facing away from the receiving cavity, the thickness of the first gasket 132 being less than the thickness of the first flange 131. Because the thickness of the first gasket 132 is relatively small, the impact energy is preferentially concentrated in the area of ​​the first gasket 132. The first thinning area 13 serves as a preset weak point to form a controllable vent. When extreme overheating occurs inside the press-fit power semiconductor module, causing the venting channel to be unable to withstand it, the impact energy of the high-temperature and high-pressure gas is pushed open through the first flange 12 by the first thinning area 13 designed in a specific direction. Its burst pressure is precisely calibrated to achieve the active directional venting function, guiding the destructive energy to a controllable path for release, achieving rapid energy dispersion and dissipation, and actively isolating the fault point of the chip component to ensure the safety goal of "failure does not propagate" for the press-fit power semiconductor module is achieved.

[0032] In one embodiment, the thickness of the first gasket 132 is more than 50% smaller than the thickness of the first flange 12. This allows the first gasket 132 to be broken open more quickly by the impact energy of the high-temperature, high-pressure gas, further enhancing the gas release efficiency. In this embodiment, the thickness of the first gasket 132 is 0.25mm to 0.35mm, for example, 0.3mm; the thickness of the first flange 12 is 0.75mm to 0.85mm, for example, 0.8mm.

[0033] In one embodiment, continue to refer to Figure 3The number of openings 8 is multiple, including a first opening 81 and a second opening 82. The size of the first opening 81 is greater than or equal to the size of the second opening 82. In this embodiment, preferably, the size of the first opening 81 is relatively large, which accelerates the release of high-temperature and high-pressure gas through the opening 8, improves the impact energy release efficiency, and achieves rapid energy dissipation. The size of the second opening 82 is relatively small, which can retain more load-bearing area. It can further balance the mechanical strength of the explosion-proof positioning frame while releasing high-temperature and high-pressure gas. That is, the size of the first opening 81 is greater than the size of the second opening 82, which can meet the requirements of high impact energy release efficiency of high-temperature and high-pressure gas and high mechanical strength of explosion-proof positioning frame 2, thereby improving the reliability and safety of press-fit semiconductor power module.

[0034] In other embodiments, while balancing the requirements of high efficiency in releasing the impact energy of high-temperature and high-pressure gases and high mechanical strength of the explosion-proof positioning frame, the size of the first opening can be larger than the size of the second opening. The first and second openings have the same size and are evenly distributed on the side surface of the explosion-proof positioning frame away from the pipe cover. The first and second openings are independently configured.

[0035] In one embodiment, in conjunction with reference Figure 1 , Figure 4 and Figure 7The tube socket 5 includes a second main electrode 51, a second flange 52, and an insulating shell 53. The second main electrode 51 and the first main electrode 11 are disposed opposite each other. The second flange 52 surrounds and is connected to the second main electrode 51 in the circumferential direction. The insulating shell 53 is located on the second main electrode 51 and surrounds the receiving cavity. One end of the insulating shell 53 is connected to the second flange 52, and the other end is connected to the tube cover 1. Specifically, one end of the insulating shell 53 is connected to the second flange 52, and the other end is connected to the first flange 12 of the tube cover 1. The press-fit power semiconductor module also includes a second thinning region 54. The second thinning region 54 includes a second through hole 541 extending through the second flange 52 along the thickness direction of the second flange 52 and a second gasket 542 located on the surface of the second through hole 541 facing away from the receiving cavity. The thickness of the second gasket 542 is less than the thickness of the second flange 52. Because the second gasket 542 is thinner, the impact energy is preferentially concentrated in the area of ​​the second gasket 542. The second thinning area 54, as a preset weak point, forms a controllable vent. When the opening 8 on the surface of the explosion-proof positioning frame 2, which serves as the first physical barrier on the side of the chip assembly 3 facing the second main electrode 51, cannot withstand the impact energy of the high-temperature and high-pressure gas generated due to extreme overheating, the impact energy is pushed open through the second thinning area 54 designed and oriented by the second flange 52. Its burst pressure is precisely calibrated to achieve the active directional venting function, guiding the destructive energy to a controllable path for release, realizing rapid energy dispersion and dissipation, and actively isolating the fault point of the chip assembly 3. This significantly improves the overall structural safety of the chip assembly 3 under fault conditions, ensuring that the impact energy is "guided and isolated" rather than completely "hard-resisted" by the explosion pressure, avoiding secondary disasters. This ensures that the press-fit power semiconductor module can still maintain structural integrity in extreme failure modes, greatly improving the reliability and safety of the press-fit power semiconductor module.

[0036] In one embodiment, the thickness of the second gasket 542 is more than 50% smaller than the thickness of the second flange 52. This allows the second gasket 542 to be broken open more quickly by the impact energy of the high-temperature, high-pressure gas, further enhancing the gas release efficiency. In this embodiment, the thickness of the second gasket 542 is 0.25mm to 0.35mm, for example, 0.3mm; the thickness of the second flange 52 is 0.75mm to 0.85mm, for example, 0.8mm.

[0037] In this embodiment, the connection between the tube cap 1 and the tube base 5 is achieved through a cold pressure welding process. At room temperature or a lower temperature, a specific pressure is applied to cause plastic deformation and atomic diffusion at the interface between the tube cap 1, the tube base 5, and the explosion-proof outer frame 2, forming an airtight solid connection. This creates a sealed space within the cavity, completing the packaging of the press-fit power semiconductor module.

[0038] In this embodiment, the insulating shell 53 includes a ceramic shell.

[0039] In one embodiment, the socket further includes a lead-out tube 6 for leading out electrodes of the chip assembly.

[0040] In one embodiment, the shape of the press-fit power semiconductor module can be designed as square, circular, or other geometric shapes according to application requirements. That is, the shape of the cap and socket can be square, circular, or other shapes, depending on the shape of the chip assembly. This application does not impose any limitations.

[0041] In one embodiment, continue to refer to Figure 1 It also includes: a circuit board 4 located within the receiving cavity, situated between the chip assembly 3 and the second main electrode 51; the circuit board 4 has multiple third through holes 41; the surface of the second main electrode 51 has multiple bosses 511, which pass through the third through holes 41 and are electrically connected to the chip assembly 3; wherein, there are gaps between the multiple bosses 511. During the packaging process, the multiple third through holes 41 and the multiple bosses 511 on the surface of the second main electrode 51 are arranged in a one-to-one correspondence, so that the circuit board 4 is fixedly installed at the designated position of the second main electrode 51, and the bosses 511 serve to limit the circuit board 4; due to the gaps between the multiple bosses 511, the impact energy of the high-temperature and high-pressure gas instantaneously generated by the chip assembly 3 due to faults such as short circuits can be released through the gaps, thereby achieving deceleration and cooling of the high-temperature and high-pressure gas.

[0042] Furthermore, a third main electrode (not shown) is provided on the side surface of the circuit board 4 facing the chip assembly 3, and the third main electrode is electrically connected to the chip assembly 3.

[0043] In one embodiment, circuit board 4 includes a rigid printed circuit board, a flexible printed circuit board, or a rigid-flex printed circuit board.

[0044] In one embodiment, in conjunction with reference Figures 8 to 10The chip assembly 3 includes multiple chip units 31 connected in parallel; each chip unit 31 includes a chip body 311, a first compensation plate 312, and a second compensation plate 313. The first compensation plate 312 and the second compensation plate 313 are respectively located on two opposing surfaces of the chip body 311, and the first compensation plate 312 is electrically connected to the first sub-electrode and the first main electrode 11 of the chip body 311, respectively. The second compensation plate 313 is electrically connected to the second sub-electrode and the second main electrode 51 of the chip body 311, respectively. The chip assembly 3 includes a central region 3A, a transition region 3B surrounding the central region 3A, and an edge region 3C surrounding the transition region 3B. Each chip... The first compensation plate 312 and / or the second compensation plate 313 located in the central region 3A of the plate unit 31 have a first material, the first compensation plate 312 and / or the second compensation plate 313 located in the transition region 3B have a second material, and the first compensation plate 312 and / or the second compensation plate 313 located in the edge region 3C have a third material; wherein, the thermal conductivity of the first material is greater than that of the second material, and the thermal conductivity of the second material is greater than that of the third material; the hardness of the first material is less than that of the second material, and the hardness of the second material is less than that of the third material. During operation, the temperature is highest in the central region of the chip assembly in the press-fit power semiconductor module. The relatively high thermal conductivity of the first material allows for rapid energy dissipation from the central region, thus releasing energy. Since the outer periphery of the central region 3A is protected by the transition region 3B and the edge region 3C, the hardness of the first material can be set within a relatively small range. The thermal conductivity of the second material is greater than that of the third material but less than that of the first material, and its hardness is less than that of the third material but greater than that of the first material. This moderate thermal conductivity and hardness serve as stress buffering and heat diffusion. The relatively low thermal conductivity of the third material, forming a gradient design with the thermal conductivity of the first and second materials, smoothly transitions the difference in thermal conductivity, significantly reduces the accumulation of thermal stress, avoids local energy accumulation, and facilitates the release of energy generated by the chip assembly. Furthermore, the relatively high hardness of the third material effectively constrains the deformation of the chip assembly 3, forming a gradient design with the hardness of the first and second materials. This gradient design, achieved through different mechanical strengths, effectively suppresses warping deformation of the press-fit power semiconductor module during operation. The gradient design described above achieves synergistic optimization of thermal-mechanical coupling performance, improving heat dissipation efficiency while ensuring uniform distribution of compressive stress at each contact interface and temperature uniformity of the multi-chip unit 31 when connected in parallel.

[0045] In one embodiment, the coefficient of thermal expansion of the first material is greater than that of the second material, and the coefficient of thermal expansion of the second material is greater than that of the third material. The coefficients of thermal expansion of the first, second, and third materials form a gradient design, which enables a smoother transition from the central region 3A to the edge region 3C, prevents abrupt changes in the coefficient of thermal expansion, and significantly reduces the shear stress at the interfaces between the chip assembly 3 and the first main electrode 11, and between the chip assembly 3 and the second main electrode 51.

[0046] In one embodiment, the first material is a molybdenum-copper alloy, wherein the atomic ratio of molybdenum to copper in the first material is 2 to 3, for example, 2, 2.5, or 3; the second material is a molybdenum-copper alloy, wherein the atomic ratio of molybdenum to copper in the second material is 4 to 6, for example, 4, 5, or 6; and the third material is molybdenum. In a specific embodiment, the first material is a molybdenum-copper alloy, wherein the number of molybdenum atoms in the first material is 70, the number of copper atoms is 30, and the first material is Mo. 70 Cu 30 The second material is a molybdenum-copper alloy, in which the number of molybdenum atoms is 85 and the number of copper atoms is 15. The first material is Mo. 85 Cu 15 The third material is molybdenum, with 100 molybdenum atoms and 0 copper atoms. 100 Cu0. It is known that copper has high thermal conductivity, and molybdenum has high hardness. The number of copper atoms in the first material is greater than that in the second material, and the number of copper atoms in the second material is greater than that in the third material. This results in the first material having a higher thermal conductivity than the second material, and the second material having a higher thermal conductivity than the third material. Conversely, the number of molybdenum atoms in the first material is less than that in the second material, and the number of molybdenum atoms in the second material is less than that in the third material. This results in the first material having a lower hardness than the second material, and the second material having a lower hardness than the third material. By employing the above ratio of molybdenum and copper atoms in the first, second, and third materials, heat dissipation efficiency is improved while ensuring optimal performance by ensuring uniform distribution of compressive stress at each contact interface when multiple chip units are connected in parallel.

[0047] In one embodiment, the chip unit 31 further includes a spring pin 316, one end of which is electrically connected to the third sub-electrode of the chip body 311, and the other end of which is electrically connected to the third main electrode of the side surface of the circuit board 4 facing the chip assembly 3.

[0048] In one embodiment, continue to refer to Figure 9The chip unit 31 further includes: a first weld body 314 located between the chip body 311 and the first compensation plate 312, the first weld body 314 connecting the first sub-electrode of the chip body 3111 and the first compensation plate 312; and a second weld body 315 located between the chip body 311 and the second compensation plate 313, the second weld body 315 connecting the second sub-electrode of the chip body 311 and the second compensation plate 313.

[0049] In one embodiment, the material of the first weld body 314 includes silver, and the material of the second weld body 315 includes silver. Specifically, the first weld body 314 includes a silver film or silver paste, and the second weld body 315 includes a silver film or silver paste. The connection between the first sub-electrode of the chip body 311 and the first compensation plate 312, and between the second sub-electrode of the chip body 311 and the second compensation plate 313, is achieved through a double-sided silver sintering process. This improves the high consistency between each chip unit 31, thereby enhancing the uniformity of pressure during the pressing process of the press-fit power semiconductor module and improving the current sharing characteristics of the press-fit power semiconductor module.

[0050] In this embodiment, the first sub-electrode is the collector, the second sub-electrode is the emitter, and the third sub-electrode is the gate. For illustration, the press-fit power semiconductor module includes a press-fit insulated gate bipolar transistor (IGBT). In other embodiments, the press-fit power semiconductor module includes other power semiconductor modules. The first sub-electrode, the second sub-electrode, and the third sub-electrode can be configured according to actual needs.

[0051] In one embodiment, the chip unit further includes: an assembly fixture and an insulating encapsulant (not shown). The chip body 311, the first compensation plate 312, and the second compensation plate 313 are all located in the assembly fixture. One end of the spring pin 316, which is electrically connected to the third sub-electrode of the chip body 311, is located in the assembly fixture, while the other end, which is electrically connected to the third main electrode on the side surface of the circuit board 4 facing the chip assembly 3, protrudes from the assembly fixture. The insulating encapsulant covers the chip body 311, the first compensation plate 312, the second compensation plate 313, and the spring pin 316, exposing the side surface of the first compensation plate 312 facing the tube cap 1, the side surface of the second compensation plate 313 facing the tube seat 5, and the side surface of the spring pin 316 facing the circuit board 4. The material of the insulating encapsulant includes epoxy resin-based or silicone-based materials.

[0052] In one embodiment, multiple parallel-connected chip units 31 are arranged in a planar array. In other embodiments, the chip assembly may also include a single chip unit.

[0053] In summary, the press-fit power semiconductor module provided in this embodiment optimizes the material properties (thermal conductivity and hardness) of the first compensation plate 312 and the second compensation plate 313 inside the chip assembly 3, resulting in a gradient layout from the center to the edge of the chip assembly 3. Furthermore, it features a venting channel 7 on the surface of the first main electrode 11 facing the chip assembly 3, extending to the edge of the first main electrode 11; an opening 8 extending from the inner wall of the explosion-proof positioning frame 2 to the outer wall of the explosion-proof positioning frame 2 on the surface away from the tube cover 1; and a gap between multiple protrusions 511 on the surface of the second main electrode 51, forming a first thinning region 13 and a second thinning region 54. These structural features work together to prevent the sudden generation of high-temperature, high-pressure gas due to a short circuit or other fault in the chip assembly 3. When impacted, the first compensation plate 311 and the second compensation plate 312 quickly discharge the impact energy generated by the chip assembly 3. The impact energy of the chip assembly 3 facing the tube cover 1 is led out to the edge of the first main electrode 11 through the discharge channel 7. In extreme overheating, the impact energy is discharged directionally by breaking open the first thinning zone 13. The impact energy of the chip assembly 3 facing the tube seat 5 is discharged through the opening 8 and the gap. In extreme overheating, the impact energy is discharged directionally by breaking open the second thinning zone 54. The explosion-proof positioning frame 2 itself is integrally formed or assembled from high-strength insulating composite material, which has excellent mechanical strength and electrical insulation properties. It can directly absorb and block most of the impact energy at the beginning, effectively protecting the tooling of the tube seat 5, the chip assembly 3 and the tube cover 1 from damage. As can be seen, the press-fit power semiconductor module of this application has an integrated design of "impact blocking - gas collection - buffer expansion - directional discharge", which not only significantly improves the safety of the chip assembly structure under chip unit failure, but also effectively guides the destructive energy to a controllable path for release. By "guiding and isolating" rather than completely "hard resisting", it achieves rapid energy dispersion and dissipation, actively isolates the fault point, and thus ensures that the power module can maintain structural integrity in extreme failure modes, avoid secondary disasters, and ensure the safety goal of "failure not escalating", which greatly improves the reliability and safety of the press-fit power semiconductor module.

[0054] This embodiment also provides a method for fabricating a press-fit power semiconductor module, including: Provide a tube seat 5, the interior of which has a receiving cavity; A chip assembly 3 and an explosion-proof positioning frame 2 are formed. One side surface of the explosion-proof positioning frame 2 has an opening 8 extending from the inner sidewall of the explosion-proof positioning frame 2 to the outer sidewall of the explosion-proof positioning frame 2. Chip assembly 3 and explosion-proof positioning frame 2 are placed sequentially in the receiving cavity. The explosion-proof positioning frame 2 surrounds the side wall of chip assembly 3, and the opening 8 is set facing the bottom of tube seat 5. A tube cap 1 is formed and covered on a tube seat 5, with the tube cap 1 and tube seat 5 being sealed together; wherein, the tube cap 1 includes a first main electrode 11, the chip assembly 3 and the first main electrode 11 are disposed opposite to and in contact with each other, and the surface of the first main electrode 11 facing the chip assembly 3 has a discharge channel 7 and the discharge channel 7 extends to the edge of the first main electrode 11.

[0055] In one embodiment, a method for forming a chip assembly 3 includes forming a plurality of chip cells 31 and connecting the plurality of chip cells 31 in parallel via a circuit board 4. In other embodiments, a single chip cell 31 may be formed.

[0056] In this embodiment, the step of forming a plurality of chip units 31 includes: forming a first compensation plate 312 and a second compensation plate 313 on two opposing surfaces of a chip body 311; the first compensation plate 312 is electrically connected to a first sub-electrode of the chip body 311, and the second compensation plate 313 is electrically connected to a second sub-electrode of the chip body 311. The chip body includes a third sub-electrode disposed on the same side surface as the second sub-electrode of the chip body 311, and the step of forming a plurality of chip units 31 further includes: forming a spring pin 316 on the third sub-electrode of the chip body 311.

[0057] The steps of forming a first compensation plate 312 and a second compensation plate 313 on two opposing surfaces of the chip body 311 include: transferring a first weld body 314 to the surface of the first compensation plate 312 and transferring a second weld body 315 to the surface of the second compensation plate 313; setting the side surface of the first compensation plate 312 with the first weld body 314 facing the side surface of the chip body 311 with the first sub-electrode, and performing a sintering process; setting the side surface of the second weld body 315 with the second weld body 315 facing the side surface of the chip body 311 with the second sub-electrode, and performing a sintering process.

[0058] In this embodiment, the first weldment 314 is transferred to the surface of the first compensation plate 312 by brushing, and the second weldment 315 is transferred to the surface of the second compensation plate 313 by brushing. In other embodiments, the first weldment is transferred to the surface of the first compensation plate by other transfer methods, and the second weldment is transferred to the surface of the second compensation plate by other transfer methods.

[0059] In one embodiment, the sintering process is completed in stages within a temperature range of 200°C to 300°C, and the pressure during the sintering process is maintained at 0.5 MPa to 15 MPa. This sintering process is a conventional setup in the art, and can be customized according to actual needs.

[0060] In one embodiment, the step of forming multiple chip units 31 further includes: placing the chip body 311, the first compensation plate 312, the second compensation plate 313, and the spring pin 316 together in an assembly fixture; applying insulating encapsulant, followed by a curing process. The curing process involves staged temperature increases for curing according to actual needs, forming chip units 31 with electrical insulation properties and mechanical protection functions.

[0061] In one embodiment, before placing the chip assembly 3 and the explosion-proof positioning frame 2 sequentially in the receiving cavity, the method further includes: placing a circuit board 4 in the receiving cavity, the circuit board having a plurality of third through holes 41, and the surface of the circuit board 4 facing the chip assembly 3 having a third main electrode (not shown).

[0062] In one embodiment, the tube socket 5 includes a second main electrode 51, a second flange 52, and an insulating shell 53. The second main electrode 51 and the first main electrode 11 are disposed opposite to each other. The second flange 52 surrounds and connects to the second main electrode 51 in the circumferential direction. The insulating shell 53 is located on the second main electrode 52 and surrounds the receiving cavity. The surface of the second main electrode 51 has multiple bosses 511. During the placement of the circuit board 4 in the receiving cavity, the multiple bosses 511 and multiple third through holes 41 are arranged in a one-to-one correspondence. The surface of the circuit board 4 is in contact with the surface of the second main electrode 51 located between the multiple bosses 511. Specifically, the circuit board 4 is fixedly installed in the designated position of the second main electrode 51 by predetermined fastening screws to ensure the stability of the electrical connection and the reliability of the mechanical fixation.

[0063] In one embodiment, the step of covering the tube seat 5 with a tube cap 1 and sealing the tube cap 1 and tube seat 5 includes: performing a cold pressure welding process on the tube cap 1, tube seat 5, explosion-proof positioning frame 2, chip assembly 3, and circuit board 4 located in the receiving cavity, so that the chip assembly 3 is electrically connected to the first main electrode 11, the chip assembly 3 is electrically connected to the second main electrode 51, and the chip assembly 3 is electrically connected to the circuit board 4. Specifically, in each chip unit 31, the first sub-electrode of the chip body 311 is electrically connected to the first main electrode 11, the second sub-electrode of the chip body 311 is electrically connected to the second main electrode 51, and the third sub-electrode of the chip body 311 is electrically connected to the third main electrode of the circuit board 4. Under room temperature or lower temperature conditions, by applying specific pressure, plastic deformation and atomic diffusion are generated at the joint interface of the tube cap 1, tube seat 5, and explosion-proof outer frame 2, forming an airtight solid connection, so that the receiving cavity forms a sealed space, completing the packaging of the press-fit power semiconductor module. This method has simple process steps, reliable connection, and effectively improves the heat dissipation performance and mechanical strength of the press-fit power semiconductor module.

[0064] In one embodiment, the tube cover 1 further includes: a first flange 12, which surrounds and is connected to the first main electrode 11 in the circumferential direction; in the step of covering the tube cover 1 on the tube seat 5 and sealing the tube cover 1 and the tube seat 5, one end of the insulating shell 53 of the tube seat 5 is connected to the second flange 52, and the other end is connected to the first flange 12 of the tube cover 1.

[0065] The same content as the press-fit power semiconductor module provided in this embodiment and the previous embodiments will not be repeated.

[0066] It should be understood that the terms "mechanism," "device," "component," etc., used in this application are merely one method of distinguishing different components, elements, parts, sections, or assemblies at different levels. However, if other terms can achieve the same purpose, they can be replaced by other expressions.

[0067] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention. In practical applications, the technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification, and various changes can be made to them in form and detail without departing from the spirit and scope of the present invention.

Claims

1. A press-fit power semiconductor module, characterized in that, include: Tube seat, the tube seat having an internal receiving cavity; A tube cap is located on the tube seat and is sealed to the tube seat; the tube cap includes a first main electrode; The chip assembly and the explosion-proof positioning frame are located within the receiving cavity. The chip assembly and the first main electrode are opposite to and in contact with each other. The explosion-proof positioning frame surrounds the side wall of the chip assembly. The first main electrode has a venting channel on the side of its surface facing the chip assembly, and the venting channel extends to the edge of the first main electrode. The explosion-proof positioning frame has an opening on the side surface opposite to the pipe cover, extending from the inner wall of the explosion-proof positioning frame to the outer wall of the explosion-proof positioning frame.

2. The press-fit power semiconductor module according to claim 1, characterized in that, The discharge channel includes a central groove, an annular groove, and a connecting groove; the central groove is located at the center of the first main electrode, the annular groove is arranged around the central groove, and the connecting groove connects the central groove and the annular groove, and the annular groove extends to the edge of the first main electrode.

3. The press-fit power semiconductor module according to claim 2, characterized in that, The number of annular grooves is multiple, including a first annular groove to an Nth annular groove; N is an integer greater than or equal to 2; the first annular groove is arranged around the central groove, and the nth annular groove is arranged around the (n-1)th annular groove, where n is an integer greater than or equal to 2 and less than or equal to N; The connecting groove connects the central groove and the first annular groove, connects the nth annular groove and the (n-1)th annular groove, and connects the Nth annular groove to the edge of the first main electrode.

4. The press-fit power semiconductor module according to claim 3, characterized in that, At least two of the connecting grooves connecting the central groove and the first annular groove, the connecting grooves connecting the nth annular groove and the (n-1)th annular groove, and the connecting grooves connecting the Nth annular groove to the edge of the first main electrode are arranged opposite to each other or staggered.

5. The press-fit power semiconductor module according to claim 1, characterized in that, The number of openings is multiple, including a first opening and a second opening, wherein the size of the first opening is greater than or equal to the size of the second opening.

6. The press-fit power semiconductor module according to claim 1, characterized in that, The pipe cover further includes: a first flange, which surrounds the first main electrode in the circumferential direction and is connected to the first main electrode; The press-fit power semiconductor module further includes a first thinning region, the first thinning region including a first through hole penetrating the first flange along the thickness direction of the first flange and a first gasket located on the surface of the first through hole opposite to the receiving cavity, the thickness of the first gasket being less than the thickness of the first flange.

7. The press-fit power semiconductor module according to claim 1, characterized in that, The tube seat includes a second main electrode, a second flange, and an insulating shell. The second main electrode and the first main electrode are disposed opposite to each other. The second flange surrounds the second main electrode in the circumferential direction and is connected to the second main electrode. The insulating shell is located on the second main electrode and surrounds the receiving cavity. One end of the insulating shell is connected to the second flange, and the other end is connected to the tube cover. The press-fit power semiconductor module further includes a second thinning region, the second thinning region including a second through hole penetrating the second flange along the thickness direction of the second flange and a second gasket located on the surface of the second through hole opposite to the receiving cavity, the thickness of the second gasket being less than the thickness of the second flange.

8. The press-fit power semiconductor module according to claim 7, characterized in that, It also includes: a circuit board located within the receiving cavity, the circuit board being situated between the chip assembly and the second main electrode; the circuit board having a plurality of third through holes; The surface of the second main electrode has multiple protrusions, which pass through the third through hole and are electrically connected to the chip assembly; wherein there are gaps between the multiple protrusions.

9. The press-fit power semiconductor module according to claim 7, characterized in that, The chip assembly includes multiple chip units connected in parallel; each chip unit includes a chip body, a first compensation plate, and a second compensation plate, wherein the first compensation plate and the second compensation plate are respectively located on two opposite surfaces of the chip body, and the first compensation plate is electrically connected to the first sub-electrode and the first main electrode of the chip body, and the second compensation plate is electrically connected to the second sub-electrode and the second main electrode of the chip body. The chip assembly includes a central region, a transition region surrounding the central region, and an edge region surrounding the transition region. In each chip unit, the first compensation plate located in the central region and / or the second compensation plate located in the central region has a first material; the first compensation plate located in the transition region and / or the second compensation plate located in the transition region has a second material; and the first compensation plate located in the edge region and / or the second compensation plate located in the edge region has a third material. The thermal conductivity of the first material is greater than that of the second material, and the thermal conductivity of the second material is greater than that of the third material. The hardness of the first material is less than that of the second material, and the hardness of the second material is less than that of the third material.

10. The press-fit power semiconductor module according to claim 9, characterized in that, The first material is a molybdenum-copper alloy, wherein the ratio of molybdenum to copper atoms in the first material is 2 to 3; the second material is a molybdenum-copper alloy, wherein the ratio of molybdenum to copper atoms in the second material is 4 to 6; and the third material is molybdenum.

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