Forming die for crimping type packaging shell of semiconductor IGBT (Insulated Gate Bipolar Translator)

Abstract

The invention relates to the technical field of semiconductor packaging molds, in particular to a semiconductor IGBT crimping type packaging shell forming mold which comprises a fixed mold body and a movable mold body which are matched with each other, a movable insert used for installing terminal hardware and a double-push-plate structure used for demolding. The movable die comprises an upper base plate and an upper die which are arranged up and down, and guide columns are arranged at corners of the upper base plate; the fixed mold comprises a lower mold plate and a bottom plate which are arranged up and down, two lower cushion blocks are symmetrically arranged between the lower mold plate and the bottom plate, and a top cavity is defined by the lower mold plate, the bottom plate and the lower cushion blocks; a cargo mold used for fixing the movable insert, packaging flange hardware and containing a composite material is embedded in the middle of the lower mold plate, and the upper mold and the cargo mold are connected in a mold closing and pressing mode. The lower template is provided with a guide channel corresponding to the guide post; a plurality of ejector pins vertically penetrate through the ejector cavity, the bottom ends of the ejector pins are fixed to the bottom plate, and meanwhile the top ends of the ejector pins are located in the cargo mold. The method has the characteristic of reducing the comprehensive cost.

Description

Technical Field

[0001] This application relates to the field of semiconductor packaging mold technology, and in particular to a semiconductor IGBT press-fit packaging shell forming mold. Background Technology

[0002] IGBTs (Insulated Gate Bipolar Transistors) are core components in the field of power electronics, capable of efficiently controlling large currents and high voltages, and are widely used in frequency converters, electric vehicles, new energy, and other fields. Their packaging primarily serves to protect the chip, provide efficient heat dissipation, and facilitate circuit connections.

[0003] In related technologies, the conventional manufacturing of IGBT press-fit package housings for semiconductors mainly relies on CNC machining of substrates. The housing structure is formed through milling and drilling, and then the metal inserts are fixed by bonding or welding. However, as power modules develop towards higher density and miniaturization, traditional processing methods are no longer sufficient to meet the demands of large-scale production. In recent years, the industry has begun to explore the use of mold forming technology to replace CNC machining. This solution, when producing the main body of the IGBT press-fit power module package housing, requires first placing the terminal metal parts and the packaging flange metal parts as inserts into the mold, then adding an equivalent amount of composite material before closing the mold to form the final shape.

[0004] The existing manufacturing methods for IGBT press-fit package housings suffer from the following problems: low CNC material utilization, long processing cycles, high labor costs, and insufficient connection strength of the separate metal inserts, which can easily affect the reliability and lifespan of the module; existing mold structures are complex, demolding efficiency is low, and integrated and precise positioning of the metal inserts has not yet been achieved. These problems all contribute to the high production cost of IGBT package housings, severely restricting the widespread application of power modules. Summary of the Invention

[0005] To reduce overall costs, this application provides a molding die for a semiconductor IGBT press-fit package housing.

[0006] The technical solution for the semiconductor IGBT press-fit package housing molding die provided in this application is as follows: A semiconductor IGBT press-fit package housing molding die, characterized in that it includes a fixed mold and a moving mold that cooperate with each other, a movable insert for mounting terminal hardware, and a double push plate structure for demolding; the moving mold includes an upper pad plate and an upper mold arranged vertically, and guide posts are provided at the corners of the upper pad plate; the fixed mold includes a lower template plate and a base plate arranged vertically, and two lower pad blocks are symmetrically arranged between the lower template plate and the base plate, and the three together form a top cavity; a mold for fixing the movable insert, the package flange hardware, and accommodating the composite material is embedded in the middle of the lower template plate, and the upper mold and the mold are pressed together; the lower template plate has a guide channel corresponding to the guide post; multiple ejector pins are vertically inserted in the top cavity, the bottom ends of the multiple ejector pins are fixed to the base plate, and the top ends are located in the mold.

[0007] By adopting the above technical solution, composite materials and hardware inserts are integrally pressed into the target structure, realizing one-time molding of semiconductor IGBT press-fit package shells with a single mold. After molding, the product is ejected synchronously through ejector pins and double push plate structure, which effectively reduces manual labor dependence, processing cycle and material waste compared with traditional CNC machining, and significantly reduces the overall cost.

[0008] Preferably, a clamping plate and a lower pad are sequentially provided on the base plate, and a connecting column penetrating the clamping plate and the lower pad is circumferentially provided between the base plate and the lower template.

[0009] By adopting the above technical solution, the circumferentially distributed connecting columns penetrate the clamping plate and the lower pad plate, which strengthens the connection rigidity between the base plate and the lower template, reduces the stress deformation of the mold during pressing and forming, and ensures the forming accuracy.

[0010] Preferably, the double push plate structure includes two hydraulic cylinders, which are respectively inverted and fixed at both ends of the clamping plate and located outside the top cavity. The piston rod of the hydraulic cylinder passes through the clamping plate and engages with the shaft hole of the bottom plate.

[0011] By adopting the above technical solution, the symmetrical layout of the dual oil cylinders not only optimizes the spatial distribution, but also provides stable and balanced ejection power, making the ejector pins more uniformly stressed and reducing deformation and damage during demolding.

[0012] Preferably, the outer perimeter of the mold has four identical inclined tops, the outer wall of each inclined top has a first inclined surface, and the inner wall has a protruding structure; the upper mold has four inclined guide blocks with complementary angles around its perimeter, corresponding to the first inclined surface of the inclined tops.

[0013] By adopting the above technical solution, when the upper mold moves downward, the inclined guide blocks around it will precisely push the four inclined tops toward the mold, so that the protruding structure of the inner wall of the inclined tops fits the mold and together forms the side molding cavity of the IGBT package shell, realizing the precise molding of the complex structure on the side of the shell, while ensuring the symmetry and consistency of the side dimensions.

[0014] Preferably, the double push plate structure further includes eight push rods, which are arranged in pairs and tilted in four directions respectively; the bottom ends of the four sets of push rods are fixed in the lower pad plate, and the top ends penetrate into the interior of the inclined top.

[0015] By adopting the above technical solution, the inverted / complex contour structure formed by the inclined top protrusion structure on the side of the shell can be easily produced, while ensuring that the inclined tops in four directions are subjected to balanced forces, reducing product jamming and loss, and improving the smoothness of demolding and the appearance integrity of the product.

[0016] Preferably, the movable insert includes a knurled cylindrical part and a concave mold part respectively disposed on both sides of the mold. The knurled cylindrical part is threaded to the bottom of the mold, and the concave mold part is used to snap and fix the terminal hardware.

[0017] By adopting the above technical solutions, the concave mold reduces terminal displacement and tilting during press forming, ensuring the relative positional accuracy between the terminal and the package shell, and meeting the subsequent assembly requirements of IGBT; the knurled cylindrical part uses the knurling design to increase friction, facilitating quick installation, disassembly, or fine-tuning of the mold position, and improving the versatility and operational efficiency of the mold.

[0018] Preferably, the lower template has multiple heating holes horizontally extending through it at a position below the mold for placing heating rods. The multiple heating holes are arranged horizontally and at intervals, avoiding the push rod and the ejector pin.

[0019] By adopting the above technical solution, the heating rod heats the mold and surrounding molding area through the heating hole, so that the composite material reaches the appropriate pressing temperature, ensuring that the material fully fills the molding cavity, while enhancing the bonding strength with the hardware and improving the structural density of the encapsulation shell.

[0020] Preferably, the top of the upper pad, the perimeter of the lower template, and the outer side wall of the lower pad are all fitted with heat insulation boards of appropriate size.

[0021] By adopting the above technical solutions, the molding temperature fluctuation caused by heat loss is reduced, ensuring the curing / pressing quality of composite materials and product consistency. At the same time, it isolates the heat conduction of high-temperature components of the mold, prevents high temperature from affecting non-heat-resistant components around the mold, reduces the risk of burns to operators, and improves the overall service life of the mold and operational safety.

[0022] A processing method, applied to the above-mentioned semiconductor IGBT press-fit package housing molding die, is characterized by comprising the following steps: S1: The terminal hardware is precisely positioned and installed using the movable insert; the encapsulation flange hardware and the composite material are placed together in the center of the mold to complete the preset assembly.

[0023] S2: Close the mold and check for a seal; S3: Heat the mold and surrounding molding area to the temperature required for pressing; S4: Open the mold and activate the double push plate structure to eject the molded product with the ejector pins; S5: Remove manually after the mixture has cooled down. S6: Clean the mold using cleaning tools such as an air gun.

[0024] By adopting the above technical solution, the integrated molding of IGBT press-fit package shell is realized, which not only ensures the positioning accuracy and bonding stability of terminal hardware, package flange hardware and composite material, but also ensures product size compliance and structural compactness through temperature-controlled pressing and cooling shaping. At the same time, mold cleaning maintains the continuity of subsequent production. The overall process is efficient and orderly, taking into account both product quality consistency and production repeatability.

[0025] Preferably, the total process time from S1 to S6 is approximately 15 minutes.

[0026] By adopting the above technical solution, the process time can meet the capacity requirements of mass production without sacrificing molding quality in pursuit of excessive speed, thus balancing production efficiency and product yield.

[0027] In summary, this application includes at least one of the following beneficial technical effects: 1. This mold integrates composite materials and metal inserts into the target structure, realizing one-time molding of semiconductor IGBT press-fit package shells with a single mold. After molding, the product is ejected simultaneously through ejector pins and a double push plate structure, which effectively reduces reliance on manual labor, processing cycle and material waste compared with traditional CNC machining, and significantly reduces overall costs. 2. The connecting column strengthens the connection rigidity between the base plate and the lower template, reduces stress deformation, and ensures molding accuracy; the inverted layout of the dual hydraulic cylinders optimizes the spatial distribution and provides stable and balanced ejection power, making the ejector pins more evenly stressed and improving demolding smoothness. 3. The eight tilting push rods move in sync, which can easily push out the inverted / complex contour structure formed by the tilting top protrusion structure on the side of the shell. At the same time, it ensures that the tilting tops in four directions are evenly stressed, reducing product jamming and wear, and improving the smoothness of demolding and the integrity of the product's appearance. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of an embodiment of this application.

[0029] Figure 2 This is a schematic diagram of the overall structure of the moving mold in the embodiments of this application.

[0030] Figure 3 This is a schematic diagram illustrating the cooperation relationship between the hardware inserts, movable inserts, and the mold in the embodiments of this application.

[0031] Figure 4 This is a schematic diagram of the structure of the molded product in the embodiments of this application.

[0032] Figure 5 This is a schematic diagram of the overall structure of the fixed mold in the embodiments of this application.

[0033] Figure 6 This is a schematic diagram illustrating the usage scenario of the push rod in the embodiments of this application.

[0034] Explanation of reference numerals in the attached drawings: 1. Moving mold; 11. Upper backing plate; 12. Upper mold; 13. Guide pillar; 14. Angled guide block; 2. Movable insert; 21. Knurled cylindrical part; 22. Cavity mold part; 3. Terminal hardware; 4. Flange hardware; 5. Fixed mold; 51. Lower mold plate; 511. Guide channel; 512. Heating hole; 513. Top cavity; 52. Cargo mold; 521. Molding cavity; 53. Angled ejector; 531. First inclined surface; 532. Protruding structure; 54. Lower backing block; 55. Lower backing plate; 56. Clamping plate; 57. Base plate; 58. Connecting pillar; 59. Ejector pin; 6. Heat insulation plate; 7. Double push plate structure; 71. Hydraulic cylinder; 72. Push rod. Detailed Implementation

[0035] The following is in conjunction with the appendix Figure 1-6 This application will be described in further detail.

[0036] This application discloses a molding die for forming the housing of a semiconductor IGBT press-fit package. (Refer to...) Figure 1-6 A semiconductor IGBT press-fit package housing molding die includes a fixed mold 5 and a moving mold 1 that cooperate with each other, a movable insert 2 for mounting terminal hardware 3, and a double push plate structure 7 for demolding; the moving mold 1 includes an upper pad 11 and an upper mold 12 connected vertically, and guide posts 13 are fixed at the corners of the upper pad 11; the fixed mold 5 includes a lower template 51 and a base plate 57 connected vertically, and two lower pads 54 are symmetrically fixed between the lower template 51 and the base plate 57, and the three together form a top cavity 513.

[0037] Furthermore, the lower mold plate 51 is embedded in the middle to fix the movable insert 2, the encapsulated flange hardware 4, and the mold 52 for accommodating the composite material. The upper mold 12 and the mold 52 are pressed together. The lower mold plate 51 is provided with a guide channel 511 corresponding to the guide post 13. Multiple ejector pins 59 are vertically inserted in the top cavity 513. The bottom ends of the multiple ejector pins 59 are fixed on the base plate 57, while the top ends are located in the mold 52.

[0038] Correspondingly, when the mold is working, the terminal hardware 3 is first precisely installed and positioned by the movable insert 2, and then the encapsulation flange hardware 4 and the composite material are placed together in the mold 52 to complete the pre-assembly; then the moving mold 1 and the fixed mold 5 are guided by the guide post 13 and the guide channel 511 to achieve mold closing, the upper mold 12 is precisely connected with the mold 52 and pressure is applied, so that the composite material and the hardware are integrally formed under the pressure constraint; after the forming is completed, the moving mold 1 and the fixed mold 5 are separated, and multiple ejector pins 59 on the base plate 57 work together with the double push plate structure 7 in the top cavity 513 to push the formed encapsulation shell out smoothly from the mold 52, completing one forming operation.

[0039] Therefore, through the precise cooperation between the movable insert 2 and the mold 52, the mold achieves reliable positioning and integrated pressing of the terminal hardware 3, the packaging flange hardware 4, and the composite material, effectively ensuring the assembly accuracy of each component and the structural integrity of the packaging shell. The guiding design of the guide post 13 and the guide channel 511 improves the coaxiality of the mold closing, reduces the off-center load or misalignment during the pressing process, and improves the dimensional accuracy and consistency of the product. The synchronous demolding design of the double push rod 72 structure ensures that the product is subjected to uniform force during demolding, reduces the warping or breakage rate, and ensures the appearance quality and mechanical properties of the packaging shell.

[0040] In summary, the overall mold structure integrates composite materials and metal inserts into the target structure through modular design, achieving one-time molding of semiconductor IGBT press-fit package shells using a single mold. Compared with traditional CNC shell processing methods, it optimizes the assembly and operation process, making operation convenient and molding efficiency high. It effectively reduces reliance on manual labor, processing cycle and material waste, significantly reducing overall costs and reliably meeting the high-precision and high-reliability production requirements of semiconductor IGBT press-fit package shells.

[0041] Specifically, in this embodiment, a clamping plate 56 and a lower pad 55 are sequentially connected to the base plate 57. Four connecting posts 58 are circumferentially fixed between the base plate 57 and the lower template 51, penetrating the clamping plate 56 and the lower pad 55. By reliably connecting the base plate 57 and the lower template 51, and penetrating the clamping plate 56 and the lower pad 55, the connecting posts 58 achieve precise positioning and fixation of the three components, effectively improving the rigidity and coaxiality of the overall mold structure, suppressing stress deformation during mold closing and demolding processes, and enhancing the mold's load-bearing capacity and service life.

[0042] Specifically, the double push plate structure 7 includes two hydraulic cylinders 71, which are respectively inverted and fixed at both ends of the clamping plate 56 and located outside the top cavity 513. The piston rod of the hydraulic cylinder 71 passes through the clamping plate 56 and is engaged with the shaft hole of the bottom plate 57.

[0043] Therefore, the inverted embedded installation of the hydraulic cylinder 71 reduces the vertical space occupied by the top cavity 513, making the internal component layout more compact and reasonable. Through the coordinated design of the connecting column 58 and the symmetrical drive of the two hydraulic cylinders 71, the balanced transmission and precise control of the demolding power are achieved, ensuring higher synchronization and more uniform force when the lower pad 55 drives the ejector pin 59 to move. This further reduces the occurrence of warping, tearing or breakage during product demolding, ensuring the appearance quality and dimensional accuracy of the product. The addition of the clamping plate 56 and the lower pad 55 not only provides a stable installation benchmark for the hydraulic cylinder 71, but also optimizes the power transmission path, reduces power loss, and improves the controllability and smoothness of the demolding process, making it suitable for demolding requirements of different specifications of shells.

[0044] On the other hand, the outer perimeter of the mold 52 is surrounded by four identical inclined tops 53. The outer wall of the inclined tops 53 is provided with a first inclined surface 531, and the inner wall is integrally formed with a protruding structure 532. The upper mold 12 is surrounded by four inclined guide blocks 14 with complementary angles, corresponding to the first inclined surface 531 of the inclined tops 53.

[0045] Correspondingly, when the upper mold 12 moves downward, the inclined guide blocks 14 around it precisely fit with the first inclined surface 531 of the inclined top 53 and generate a squeezing effect, driving the four inclined tops 53 to move synchronously towards the center along the inclined guide until the protruding structure 532 of the insert inner wall fits tightly with the mold 52 and the material to be formed, forming a complete molding cavity 521 that matches the shape of the IGBT press-fit package shell. Then the upper mold 12 and the molding cavity 521 cooperate to complete the press-fit molding operation. When the mold is opened, the upper mold 12 drives the inclined guide blocks 14 to move upward, the squeezing force of the inclined guide blocks 14 on the inclined tops 53 disappears, the inclined tops 53 are released from the centripetal constraint and reset, separating from the formed package shell, and the product is successfully demolded with the help of the ejector pins 59.

[0046] Therefore, the four-sided enclosure structure of the four inclined tops 53 can make the molding cavity 521 uniformly stressed, reduce product deformation caused by local stress concentration during the pressing process, and ensure product quality. Through the complementary angle design of the inclined guide block 14 and the first inclined surface 531 of the inclined top 53, the automatic centripetal positioning and locking of the insert is realized when the mold is closed, ensuring the accuracy of the molding size and effectively improving the shape consistency of the package shell.

[0047] Furthermore, the raised structure 532 on the inner wall of the inclined ejector 53 can directly form a preset undercut / complex structural feature on the product surface without the need for subsequent secondary processing, simplifying the production process; its split design facilitates individual replacement after wear, reducing maintenance costs; the automatic reset of the inclined ejector 53 during mold opening reduces secondary scratches between the inclined ejector 53 and the product surface, reducing the appearance defect rate.

[0048] In addition, the double push plate structure 7 also includes eight push rods 72, which are arranged in pairs and tilted in four directions respectively; the bottom ends of the four sets of push rods 72 are fixed in the lower pad 55, and the top ends penetrate into the interior of the inclined top 53, so that the four inclined tops 53 can be pushed out at the same time.

[0049] Correspondingly, after the outer shell is pressed and molded, and the upper mold 12 drives the inclined guide block 14 to move upward to release the constraint on the inclined ejector 53, each set of inclined push rods 72, driven by the hydraulic cylinder 71, rises with the clamping plate 56 and the lower pad 55, and pushes synchronously in four directions respectively; its bottom end is fixed in the lower pad 55 to ensure the stability and synchronization of movement, and its top end penetrates into the interior of the inclined ejector 53 and acts precisely on the four inclined ejectors 53, pushing the inclined ejectors 53 to move along the preset inclined trajectory, thereby applying reverse force to the irregular structure part of the molded outer shell; at the same time, with the pushing action of the bottom ejector pin 59, the inclined ejector 53 and the molded product can be easily separated to complete the demolding operation; and after demolding, the push rod 72 drives the inclined ejector 53 to reset, waiting for the next pushing cycle.

[0050] Therefore, the eight push rods 72 are arranged in pairs and tilted in four directions, which can synchronously drive the four inclined pushers 53 to act on the irregular structural areas of the product, so that the demolding force is evenly distributed in all parts of the product, reducing product jamming and loss, and ensuring the structural integrity of the irregular parts of the package shell; the demolding design of the inclined pushers 53 is adapted to the complex structure of the package shell, without the need for additional demolding auxiliary mechanisms, simplifying the mold structure and reducing the complexity of the production process, effectively improving demolding efficiency and stability, and adapting to the mass production needs of high-precision and high-complexity structures of semiconductor IGBT press-fit package shells.

[0051] Specifically, the movable insert 2 includes a knurled cylindrical part 21 and a concave mold part 22, which are respectively fixed to both sides of the mold 52. The knurled cylindrical part 21 is threaded into the bottom of the mold 52, and the concave mold part 22 is used to snap and fix the terminal hardware 3. Among them, the knurled texture on the surface of the knurled cylindrical part 21 greatly improves the friction of the connection part, which can effectively reduce the loosening and displacement caused by alternating pressure during the mold closing and pressing process, and ensure the stability of the assembly position of the mold 52; and the threaded connection structure also has the convenience of assembly and disassembly, which facilitates quick installation, disassembly or fine adjustment of the position of the mold 52, improving the versatility and operational efficiency of the mold.

[0052] Meanwhile, the concave mold 22 achieves precise positioning and reliable fixation of the terminal hardware 3 through a snap-fit ​​structure, ensuring that the terminal hardware 3 maintains its preset posture throughout the pressing process, reducing the occurrence of displacement or tilting due to material flow or pressing force impact, ensuring the relative positional accuracy of the terminal and the package shell, and meeting the subsequent assembly requirements of IGBT; the snap-fit ​​fixing design simplifies the pre-assembly process of the terminal hardware 3, eliminating the need for additional auxiliary positioning fixtures, shortening the preparation time for a single molding, and improving production efficiency.

[0053] Furthermore, by matching the shape and structure of the die 22 with the terminal hardware 3, the composite material can be effectively prevented from seeping into the terminal assembly gap during the molding process, thereby ensuring the conductivity and structural integrity of the terminal.

[0054] On the other hand, in this embodiment, the lower template 51 is located below the mold 52 and has four horizontally penetrating heating holes 512 for placing heating rods. The four heating holes 512 are arranged horizontally and at intervals, avoiding the push rod 72 and the ejector pin 59.

[0055] Therefore, the heating rod evenly transfers the generated heat to the mold 52 and the entire molding cavity 521 through the heating hole 512, ensuring that the composite material is always in a stable and uniform temperature environment during the pressing process, reducing molding defects caused by local temperature differences, enhancing the bonding strength with the hardware, and improving the structural density and mechanical performance consistency of the encapsulation shell.

[0056] Meanwhile, the heating hole 512 avoids the layout of the push rod 72 and the ejector pin 59, which not only reduces the interference of the heating element on the movement trajectory of the demolding mechanism, ensuring the smoothness and accuracy of the demolding action, but also optimizes the space utilization inside the mold, ensuring that heating efficiency and mechanism operation stability do not affect each other, further extending the service life of key mold components, and providing a stable temperature environment for high-precision and high-reliability mass production of semiconductor IGBT press-fit package shells.

[0057] In addition, heat insulation plates 6 of appropriate size are fixed to the top of the upper pad 11, the perimeter of the lower template 51, and the outer wall of the lower pad block 54. The heat insulation plates 6 can effectively block heat from spreading to the outside of the mold and non-molding areas, reduce temperature fluctuations and heat loss, ensure that the heat generated by the heating rod is concentrated on the molding cavity 521, maintain the stable temperature field required for the molding of composite materials, reduce problems such as uneven material curing and reduced molding quality caused by heat loss, and ensure the curing / pressing quality and product consistency of composite materials.

[0058] Furthermore, the heat insulation plate 6 can also isolate the heat conduction of high-temperature components, reduce the performance degradation or deformation of external mold components caused by high temperatures, and reduce the risk of burns to operators who accidentally come into contact with high-temperature parts of the mold, thereby improving work safety and the operating environment.

[0059] The implementation principle of the semiconductor IGBT press-fit package shell molding die in this application embodiment is as follows: the mold structure integrates composite materials and hardware inserts into the target structure through modular design, realizing one-time molding of semiconductor IGBT press-fit package shells with a single mold; compared with the traditional CNC shell processing method, the assembly and operation process is optimized, the operation is convenient and the molding efficiency is high, effectively reducing manual labor dependence, processing cycle and material waste, significantly reducing the overall cost, and can stably meet the high precision and high reliability production requirements of semiconductor IGBT press-fit package shells.

[0060] This application also discloses a processing method applied to the above-mentioned semiconductor IGBT press-fit package shell forming mold, characterized by including the following steps: S1: The terminal hardware 3 is precisely positioned and installed through the movable insert 2 to ensure that the terminal always maintains the preset posture during the molding process, reducing the offset and tilt caused by material flow or pressure impact, ensuring the relative positional accuracy of the terminal and the package shell, and improving the assembly compatibility of subsequent IGBT devices. The encapsulated flange hardware 4 and the composite material are placed together in the middle of the mold 52 to complete the pre-assembly, reduce molding defects caused by material misalignment, simplify the pre-assembly process, shorten the single molding preparation time, improve production efficiency, and lay a stable foundation for subsequent integrated pressing molding.

[0061] Specifically, the terminal hardware 3 has an L-shaped irregular structure. The multiple annular protrusions on the cylindrical section of the terminal allow the composite material to fully fill the gaps between the protrusions when integrally molded with the composite material. After molding, it forms multiple annular sealing interfaces, which can block gas and liquid from penetrating through the interface between the terminal and the composite material layer by layer, thereby achieving good airtightness and watertightness. Moreover, the composite material forms a mechanical interlocking structure after being wrapped, which can generate a mutual clamping force with the composite material when the terminal is subjected to a pull force, greatly increasing the pull resistance and preventing the terminal from coming out of the composite material.

[0062] Meanwhile, the encapsulated flange hardware 4 has a long rectangular frame structure with recessed grooves on its surface and multiple evenly distributed circular holes, allowing the composite material to fill its interior and surrounding areas. This significantly increases the contact area between the hardware and the composite material, forming a "mortise and tenon"-like interlocking effect after molding. This effectively prevents relative sliding between the hardware and the composite material. By enhancing the mechanical interlocking force between the two, it reduces the hardware from falling off the composite material, improving the basic bonding force and the integrity of the structural interface.

[0063] Furthermore, the composite material uses BMC, which combines strength and rigidity, can withstand external pressure during pressing, is suitable for mold pressing processes, has high molding precision, and can accurately replicate the fitting structure of the shell and hardware inserts, improving the overall reliability of the package. BMC contains epoxy resin, which has high insulation, high heat resistance and chemical corrosion resistance, can isolate electrical interference during IGBT high-voltage operation, adapt to the heat generation environment during semiconductor operation, and meet the safety and flame retardant requirements of semiconductor devices, reducing the risk of leakage and overheating, while resisting environmental corrosion, and helping to enhance the airtightness and watertightness of the shell, jointly ensuring the safety and service life of the device.

[0064] S2: Close the mold and check the seal. This step reduces leakage of composite materials due to insufficient sealing during the pressing process by checking for potential problems such as mold fitting gaps and insert assembly seals in advance. This reduces material waste and appearance defects such as excessive flash. At the same time, it ensures that a stable pressure environment is formed inside the cavity during the pressing process, ensuring that the composite material fully fills all corners of the cavity, improving the density and shape integrity of the product structure, and providing a preliminary guarantee for the subsequent molding quality.

[0065] S3: Heat the mold 52 and the surrounding molding area to the temperature required for pressing. This step, by adapting to the curing characteristics of the composite material, ensures that the composite material maintains good fluidity and reactivity during the pressing process, ensuring a tight bond between it and the terminal hardware 3 and the packaging flange hardware 4, thereby improving the interface bonding strength. A uniform and stable temperature environment can reduce the internal stress caused by local temperature differences during the material curing process, thereby reducing product cracking and warping, effectively improving the mechanical properties and structural stability of the packaging shell, and ensuring product quality consistency.

[0066] S4: Mold opening, the double push plate structure 7 is activated in conjunction with the ejector pin 59 to eject the molded product; this step achieves smooth demolding of the molded product through the coordinated ejection design of the double push plate structure 7 and the ejector pin 59: the double push plate structure 7 provides balanced and sufficient ejection force, which, together with the multi-point ejection action of the ejector pin 59, makes the demolding force evenly distributed on the product surface, reducing product warping, breakage or tearing caused by excessive local force, and is suitable for complex structures of semiconductor packaging shells (such as irregular parts, undercut structures), ensuring the integrity of the product appearance and dimensional accuracy; the ejection operation has strong synchronization, high demolding efficiency, shortens the molding cycle, and meets the needs of mass production.

[0067] S5: After cooling, manually remove the package. This step allows the packaged shell to fully set, reducing product deformation caused by removing the package at high temperatures and further ensuring product dimensional stability and shape accuracy. The lower product temperature after cooling reduces the risk of burns during manual removal and also reduces secondary damage to the product surface (such as fingerprints and scratches) caused by high-temperature removal, improving the safety and convenience of the removal operation and ensuring the final product quality.

[0068] S6: Clean the mold using cleaning tools such as an air gun. This step involves targeted cleaning of the mold with air guns or similar tools. This quickly removes residual composite material debris, dust, and other impurities from the mold cavity, insert surfaces, and various mating gaps, reducing the impact of residual impurities on the sealing performance and material positioning accuracy of the next molding cycle. By maintaining the cleanliness of the mold cavity and components, wear on the mold surface caused by impurities can be reduced, extending the mold's service life and ensuring the consistency and stability of product quality during mass production.

[0069] Specifically, the total process time from S1 to S6 is approximately 15 minutes, of which the material placement process takes approximately 3 minutes, the mold closing and ejection process takes approximately 9 minutes, and the cooling, removal, and air gun cleaning process takes approximately 3 minutes.

[0070] Correspondingly, for precision structural components such as IGBT press-fit packaging shells, 15 minutes is a reasonable short to medium cycle time. It can meet the capacity requirements of mass production without sacrificing molding quality for excessive speed, thus balancing production efficiency and product yield. The uniform process time ensures that the molding, holding pressure, and cooling conditions of each batch of products are completely consistent, reducing product performance and size differences caused by time fluctuations. At the same time, the stable production rhythm facilitates production line scheduling and improves mold utilization. In the long run, it reduces the production cost and time cost per unit product.

[0071] In summary, this processing method achieves integrated molding of IGBT press-fit packaging shells through a complete process of "precise positioning and assembly - mold closing and sealing inspection - heating and adapting pressing - smooth ejection and demolding - cooling and shaping and part removal - mold cleaning and maintenance". It not only ensures the positioning accuracy and bonding stability of terminal hardware 3, packaging flange hardware 4 and composite material, but also ensures product size compliance and structural compactness through temperature-controlled pressing and cooling shaping. At the same time, mold cleaning maintains the continuity of subsequent production. The overall process is efficient and orderly, taking into account both product quality consistency and production repeatability.

[0072] Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meaning understood by one of ordinary skill in the art to which this application pertains. The terms "first," "second," "third," and similar terms used in this application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. The terms "an" or "a" and similar terms do not indicate a quantity limitation, but rather indicate the presence of at least one. The terms "comprising" or "including" and similar terms mean that the elements or objects preceding "comprising" or "including" encompass the elements or objects listed following "comprising" or "including" and their equivalents, and do not exclude other elements or objects. "Above," "below," "left," "right," etc., are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0073] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A molding die for forming a semiconductor IGBT press-fit package housing, characterized in that, The system includes a fixed mold (5) and a moving mold (1) that cooperate with each other, a movable insert (2) for mounting terminal hardware (3), and a double push plate structure (7) for demolding; the moving mold (1) includes an upper pad plate (11) and an upper mold (12) arranged vertically, and guide posts (13) are provided at the corners of the upper pad plate (11); the fixed mold (5) includes a lower template plate (51) and a base plate (57) arranged vertically, and two lower pad blocks (54) are symmetrically arranged between the lower template plate (51) and the base plate (57), and the three together form a The top cavity (513) is provided with a mold for fixing the movable insert (2), the encapsulating flange hardware (4) and the mold for accommodating the composite material. The upper mold (12) is pressed together with the mold (52). The lower mold (51) is provided with a guide channel (511) corresponding to the guide post (13). Multiple ejector pins (59) are vertically inserted in the top cavity (513). The bottom ends of the multiple ejector pins (59) are fixed on the base plate (57), while the top ends are located in the mold (52).

2. The semiconductor IGBT press-fit package housing forming mold according to claim 1, characterized in that, The base plate (57) is also provided with a clamping plate (56) and a lower pad plate (55) in sequence. A connecting column (58) is also provided circumferentially between the base plate (57) and the lower template (51) and passes through the clamping plate (56) and the lower pad plate (55).

3. The semiconductor IGBT press-fit package housing molding die according to claim 2, characterized in that, The double push plate structure (7) includes two oil cylinders (71). The two oil cylinders (71) are respectively inverted and fixed at both ends of the clamping plate (56) and located outside the top cavity (513). The piston rod of the oil cylinder (71) passes through the clamping plate (56) and cooperates with the shaft hole of the bottom plate (57).

4. The semiconductor IGBT press-fit package housing molding die according to claim 1, characterized in that, The outer perimeter of the mold (52) is surrounded by four identical inclined tops (53). The outer wall of the inclined tops (53) is provided with a first inclined surface (531), and the inner wall is provided with a protruding structure (532). The upper mold (12) is surrounded by four inclined guide blocks (14) with complementary angles, corresponding to the first inclined surface (531) of the inclined tops (53).

5. A semiconductor IGBT press-fit package housing forming mold according to claim 4, characterized in that, The double push plate structure (7) also includes eight push rods (72), which are arranged in pairs and tilted in four directions respectively; the bottom ends of the four sets of push rods (72) are fixed in the lower pad plate (55), and the top ends penetrate into the interior of the inclined top (53).

6. The semiconductor IGBT press-fit package housing forming mold according to claim 1, characterized in that, The movable insert (2) includes a knurled cylindrical part (21) and a concave mold part (22) respectively disposed on both sides of the mold (52). The knurled cylindrical part (21) is threadedly engaged with the bottom of the mold (52), and the concave mold part (22) is used to snap and fix the terminal hardware (3).

7. A semiconductor IGBT press-fit package housing forming mold according to claim 5, characterized in that, The lower template (51) has a plurality of heating holes (512) horizontally extending through it below the mold (52) for placing heating rods. The plurality of heating holes (512) are arranged horizontally and at intervals, avoiding the push rod (72) and the ejector pin (59).

8. A semiconductor IGBT press-fit package housing forming mold according to claim 1, characterized in that, The top of the upper pad (11), the periphery of the lower template (51), and the outer side wall of the lower pad block (54) are all fitted with heat insulation plates (6) of appropriate size.

9. A processing method applied to a semiconductor IGBT press-fit package housing forming mold according to any one of claims 1-8, characterized in that, Includes the following steps: S1: The terminal hardware (3) is precisely positioned and installed through the movable insert (2); the encapsulation flange hardware (4) and the composite material are placed together in the middle of the mold (52) to complete the preset assembly; S2: Close the mold and check for a seal; S3: Heat the mold (52) and the surrounding molding area to the temperature required for pressing; S4: Open the mold and activate the double push plate structure (7) to eject the molded product in conjunction with the ejector pin (59); S5: Remove manually after the mixture has cooled down. S6: Clean the mold using cleaning tools such as an air gun.

10. The processing method according to claim 9, characterized in that, The total process time from S1 to S6 is approximately 15 minutes.

Images