Power module capable of withdrawing needles from front side

Abstract

The utility model discloses a power module with pins withdrawn from the front surface, and belongs to the technical field of module packaging. Comprising a metalized ceramic substrate; the metal piece comprises a flat welding bottom surface and a flat welding surface, and the welding bottom surface of the metal piece is connected with the emitting electrode of the metalized ceramic substrate; and the PINs are vertically arranged on the welding surface of the metal piece. The technical scheme has the beneficial effects that the welding strength and flatness are ensured, the product layout space is saved, and the yield and the product performance are improved.

Description

Technical Field

[0001] The utility model relates to the technical field of module packaging, in particular to a power module. Background Art

[0002] Traditional leadframe pin extraction and solder paste soldering of copper pillars are widely used in semiconductor power modules. However, with increasingly stringent customer demands, these methods are no longer able to meet diverse project requirements. Currently, solder paste soldering is the primary method for pin soldering. Traditional leadframe pin extraction occupies a large amount of external space, and traditional solder paste soldering of copper pillars results in poor surface flatness and relatively low solder strength, which can easily lead to low product yields. Utility Model Content

[0003] The purpose of this utility model is to provide a power module with front-side pin-out to solve the above technical problems;

[0004] A power module with front-side pin-out, comprising:

[0005] Metallized ceramic substrate;

[0006] A metal member, the metal member comprising a flat welding bottom surface and a flat welding surface, wherein the welding bottom surface of the metal member is connected to the emitter of the metallized ceramic substrate;

[0007] A PIN needle is vertically arranged on the welding surface of the metal part.

[0008] Preferably, the PIN needle is cylindrical and is a copper PIN needle.

[0009] Preferably, the metal piece is a copper column, and the width of the metal piece is .

[0010] Preferably, the emitter of the metallized ceramic substrate is also connected to a power terminal.

[0011] Preferably, a semiconductor device is further provided on the emitter of the metallized ceramic substrate, and solder is provided between the semiconductor device and the emitter of the metallized ceramic substrate.

[0012] Preferably, the semiconductor device comprises at least a power chip and a diode, the semiconductor device is connected to the emitter of the metallized ceramic substrate via a metal bonding wire, and the semiconductor devices are connected to each other via the metal bonding wire.

[0013] Preferably, a heat dissipation substrate is further included, and the heat dissipation substrate is arranged on the back side of the metallized ceramic substrate. The area of ​​the heat dissipation substrate is larger than the area of ​​the power module.

[0014] Preferably, it further comprises a shell, which is provided on the heat dissipation substrate, or the shell is connected to the outer side of the heat dissipation substrate.

[0015] Preferably, the housing is connected to the heat dissipation substrate to form an accommodating space, in which the metallized ceramic substrate, the metal part and the PIN needle are arranged, and one end of the PIN needle extends vertically upward out of the housing.

[0016] Preferably, the solder is provided between the heat dissipation substrate and the metallized ceramic substrate.

[0017] The beneficial effects of the utility model are: ensuring the strength and flatness of welding, saving product layout space, and improving the yield rate and product performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the utility model in one embodiment;

[0019] Figure 2 It is a structural schematic diagram of another embodiment of the present utility model;

[0020] Figure 3 It is a top view of another embodiment of the present invention;

[0021] Figure 4 It is a side view of another embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the utility model arranged in parallel on a heat dissipation substrate;

[0023] Figure 6 It is a schematic diagram of the ultrasonic welding equipment used in the present utility model;

[0024] Figure 7 It is a schematic diagram of the welding head adopted in the present utility model;

[0025] Figure 8 It is a flow chart of the injection molding packaging process adopted by the utility model.

[0026] In the accompanying drawings: 1. Metallized ceramic substrate; 11. Emitter; 2. Metal parts; 3. PIN needle; 4. Power terminal; 5. Semiconductor device; 6. Heat dissipation substrate; 7. Housing; 8. Solder; 9. Ultrasonic welding equipment; 91. Welding head; 92. Vacuum adsorption hole; 10. Metal bonding wire. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features therein can be combined with each other.

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0030] A power module with pins coming out from the front, such as Figure 1 Shown, including,

[0031] Metallized ceramic substrate 1;

[0032] The metal member 2 includes a flat welding bottom surface and a flat welding surface, and the welding bottom surface of the metal member 2 is connected to the emitter 11 of the metallized ceramic substrate 1 by ultrasonic welding;

[0033] The PIN needle 3 is vertically arranged on the welding surface of the metal part 2 through ultrasonic welding.

[0034] Specifically, the utility model provides a power module with front-side pins, which connects the metal part 2 and the PIN needle 3 by ultrasonic welding, thereby ensuring the strength and flatness of the welding, saving product layout space, and improving the yield rate and product performance.

[0035] Ultrasonic welding is a direct metal-to-metal connection. The underside of metal component 2 is welded to metallized ceramic substrate 1, and the surface of metal component 2 is welded to PIN 3. The smooth metal surface ensures weld strength and smoothness. Compared to solder paste reflow, it significantly improves electrical and thermal conductivity. The high-frequency vibration waves are transmitted from the ultrasonic head to metal component 2 and metallized ceramic substrate 1, and to PIN 3 and metal component 2.

[0036] Under pressure, the two metal surfaces rub against each other to form a fusion between the molecular layers, which directly manifests as the metal being squeezed, deformed, and welded together. Therefore, the welding bond is stronger than the connection strength of the solder paste reflow method, and the deformation is controllable and stable, thereby improving the reliability of the module.

[0037] In a preferred embodiment, the PIN needle 3 is cylindrical and made of copper.

[0038] Specifically, the PIN pin 3 consists of a body and a base, with the base having a larger cross-sectional area than the body. This larger base area provides a wider contact surface, enhancing the quality of the weld. During ultrasonic welding, a larger contact surface generates more significant frictional heat and relative motion, promoting molecular fusion between the metals and increasing the reliability of the connection.

[0039] PIN 3 can be either integrated or plug-in. The plug-in design makes the module more convenient to install and maintain. Users can easily replace or repair PIN 3 without having to replace the entire module, which can significantly reduce maintenance costs and time.

[0040] The integrated PIN pin 3 can provide higher structural strength and reliability.

[0041] Reference Figure 6 、 Figure 7 The ultrasonic welding device 9 grabs the PIN 3 with the welding head 91 and accurately places the PIN 3 on the designated welding surface of the metal part 2. When the welding mode is set to the deformation mode, the welding head 91 is used to weld the PIN 3 until the deformation of the welding base of the PIN 3 reaches the preset deformation value, and then the welding is stopped.

[0042] In a preferred embodiment, the metal member 2 is cylindrical and made of copper. The width of the metal member 2 is .

[0043] Specifically, the metal piece 2 and the PIN needle 3 are made of the same material, which can be better welded together. The metal piece 2 can be a copper column. The cylindrical metal piece 2 is easy to process and can be made by stamping technology or cutting technology.

[0044] Through stamping or cutting technology, the required shape can be produced quickly and accurately, reducing production time and cost, making the subsequent assembly process more convenient and effectively improving production efficiency.

[0045] By using stamping or cutting technology to manufacture the metal part 2, the waste of raw materials can be reduced and the production process can be optimized. The simplicity of the cylindrical design also makes the investment in molds and equipment relatively low, further reducing the overall production cost.

[0046] The cylindrical shape of the metal component 2 allows for better docking with other components (such as the PIN 3) during assembly, providing a larger contact area for easier soldering. This shape also simplifies positioning of the metal component 2 within the package, helping to ensure the stability and consistency of the overall structure.

[0047] The width of the copper column is , making it able to adapt to electronic components of different sizes and power requirements. This adaptability allows manufacturers to quickly adjust production lines according to the needs of different products and meet market changes.

[0048] On the other hand, it provides good mechanical strength, making it difficult to bend or deform during use, ensuring the stability and reliability of the metal part 2.

[0049] The ultrasonic welding equipment 9 grabs the metal part 2 through the welding head 91 and places the metal part 2 on the set position of the metallized ceramic substrate 1. When the ultrasonic welding equipment 9 is set to the deformation mode, the welding head 91 of the ultrasonic welding equipment 9 is used to weld the welding bottom surface of the metal part 2 to be welded and the emitter 11 until the deformation of the welding bottom surface of the metal part 2 reaches the preset deformation amount and the welding is stopped.

[0050] Metallized ceramic substrate 1, metal component 2, and PIN pin 3 are all made of copper. Copper is an excellent conductor, effectively reducing resistance in electronic components and ensuring fast signal transmission. Coating the surface of metallized ceramic substrate 1 with a conductive copper layer further enhances its conductivity, making it suitable for high-frequency and high-power applications.

[0051] Copper has excellent thermal conductivity, which helps to dissipate heat effectively, reducing heat buildup in electronic devices and extending the life of components.

[0052] The metallized ceramic substrate 1 can withstand high temperatures and has good thermal stability, maintaining its performance in high-temperature environments. The metallized ceramic substrate 1 provides good mechanical strength, maintaining its shape and performance under high load conditions, and preventing damage.

[0053] Compared to solder paste reflow, electrical and thermal conductivity are significantly improved. The ultrasonic head vibrates, transmitting high-frequency vibration waves to the metal component 2 and metallized ceramic substrate 1, and the PIN pin 3 and metal component 2. Under pressure, friction between the two metal surfaces creates a molecular fusion bond. This results in a stronger solder joint than solder paste reflow, and controllable, stable deformation, improving module reliability.

[0054] In a preferred embodiment, referring to Figure 2 、 Figure 3 The emitter 11 of the metallized ceramic substrate 1 is also connected to the power terminal 4 by ultrasonic welding.

[0055] Specifically, the ultrasonic welding device 9 welds the bottom of the power terminal 4 to the emitter 11 of the metallized ceramic substrate 1 through the welding head 91. It is responsible for transmitting current, enabling the module to be effectively electrically connected to other electronic components and ensuring smooth flow of current.

[0056] In a preferred embodiment, the semiconductor device 5 includes at least a power chip and a diode. The semiconductor device 5 is connected to the emitter 11 of the metallized ceramic substrate 1 via a metal bonding wire 10 , and the semiconductor devices 5 are connected to each other via a metal bonding wire 10 .

[0057] Specifically, at least one semiconductor device 5 is provided on the conductive copper layer of the metallized ceramic substrate 1 and is soldered to the conductive copper layer.

[0058] The semiconductor device 5 includes at least one power chip and one diode. Metal bonding wires are used to electrically connect the bonding surface of the power chip and the bonding surface of the diode, the power chip and the corresponding metallized ceramic substrate 1, and the diode and the corresponding metallized ceramic substrate 1.

[0059] Metal bonding wires are made of aluminum or copper. Aluminum is cheaper than copper, reducing overall costs. Aluminum's low density reduces device weight, and its low melting point ensures good bonding during soldering. Furthermore, aluminum's excellent oxidation resistance can prevent degradation of the bonded joint to a certain extent.

[0060] Copper's electrical conductivity is much higher than aluminum, effectively reducing power consumption and heat generation in high-current applications. Copper also has high thermal conductivity, effectively conducting heat and dissipating it, improving the performance and reliability of semiconductor devices.

[0061] Copper is generally mechanically stronger than aluminum, better able to withstand external stresses and suitable for high-power applications. When properly processed, copper is also corrosion-resistant and durable.

[0062] In a preferred embodiment, a heat dissipation substrate 6 is further included. The heat dissipation substrate 6 is disposed on the back side of the metallized ceramic substrate 1 , and the area of ​​the heat dissipation substrate 6 is larger than the area of ​​the power module.

[0063] Specifically, refer to Figure 4 、 Figure 5 Three half-bridge modules (power modules) are arranged on a heat sink substrate 6. The heat sink substrate 6, with a larger surface area than the power modules, more effectively absorbs and dissipates heat generated by the power modules, thereby reducing the modules' operating temperature and extending their service life. The large surface area of ​​the heat sink 6 helps evenly distribute heat, prevents local overheating, and improves the thermal stability of the entire system.

[0064] In a preferred embodiment, it further includes a housing 7, which is disposed on the heat dissipation substrate 6, or the housing 7 is connected to the outer side of the heat dissipation substrate 6;

[0065] The housing 7 is connected to the heat dissipation substrate 6 to form an accommodating space. The accommodating space contains the metallized ceramic substrate 1 , the metal part 2 and the PIN needle 3 . One end of the PIN needle 3 extends vertically upward out of the housing 7 .

[0066] Specifically, the housing 7 is formed by injection molding, referring to Figure 4 The housing 7 is provided on the heat dissipation substrate 6, and the housing 7 is connected to the heat dissipation substrate 6 to form an accommodating space. The accommodating space is provided with:

[0067] Metallized ceramic substrate 1, metal part 2 and PIN pin 3, one end of PIN pin 3 vertically extends upward out of housing 7 to form an external connecting part.

[0068] The emitter 11 of the metallized ceramic substrate 1 is also welded with a power terminal 4, which is responsible for transmitting current, enabling the module to be effectively electrically connected to other electronic components and ensuring smooth flow of current.

[0069] Reference Figure 1 The housing 7 is connected to the outside of the heat sink 6. The housing 7 encapsulates the heat sink 6, metallized ceramic substrate 1, metal component 2, and PIN 3. One end of the PIN 3 extends vertically upward from the housing 7 to form an external connector. This overcomes the problem of conventional plastic-encapsulated power modules where the terminal pins are encapsulated on the side of the housing 7, preventing the PIN 3 from being exposed from the top of the module.

[0070] Different connection methods can encapsulate the metallized ceramic substrate 1 , the metal part 2 , the PIN needle 3 , and the semiconductor device 5 inside the housing 7 , thereby ensuring the safety and sealing of the power module.

[0071] One end of the PIN pin 3 extends vertically upward out of the housing 7, realizing a packaging structure in which the plastic-encapsulated power module leads to external electrical connection components from the top of the module.

[0072] The metal part 2 and the PIN needle 3 are both welded by ultrasonic welding, eliminating the involvement of the reflow process, reducing the failure factors in the reflow process, improving the welding bonding strength of the PIN needle 3, optimizing the process, and improving the reliability of the module.

[0073] In a preferred embodiment, a semiconductor device 5 is further provided on the emitter 11 of the metallized ceramic substrate 1 , and a solder 8 is provided between the semiconductor device 5 and the emitter 11 of the metallized ceramic substrate 1 ;

[0074] Solder 8 is provided between the heat dissipation substrate 6 and the metallized ceramic substrate 1 . The solder 8 includes at least one of tin-lead, tin-silver, tin-silver-copper, and lead-tin-silver.

[0075] Specifically, the solder 8 is made of one of Sn-containing solder materials such as SnPb, SnAg, SnAgCu, and PbSnAg, and the maximum soldering temperature is controlled at within the range.

[0076] The tin in the solder 8 has good electrical conductivity and can form a low-impedance electrical connection. In particular, in a molten state, metals such as tin and silver can flow quickly to fill tiny gaps and reduce contact resistance.

[0077] The thermal conductivity of metals such as tin and silver is relatively high, and the interface formed by the solder 8 after connection can effectively conduct heat, thereby reducing the operating temperature of the device and avoiding performance degradation due to overheating.

[0078] The metal connection formed by the solder 8 after cooling and solidification has certain toughness and strength. In particular, the tin-lead alloy has good ductility at high temperatures and can effectively withstand the stress caused by thermal expansion.

[0079] The maximum welding temperature is controlled at The range of the welding temperature can effectively reduce the thermal stress generated during welding, making the material smoother during welding and cooling, reducing stress concentration and preventing mechanical failure.

[0080] Ultrasonic welding is a welding technique used for direct metal-to-metal connections. During this process, the underside of metal component 2 is welded to metallized ceramic substrate 1, while the surface of metal component 2 is welded to PIN 3. Because the metal surfaces to be welded are flat, both weld strength and smoothness are ensured.

[0081] Compared to traditional solder paste reflow soldering, this welding technology uses high-frequency vibration waves generated by an ultrasonic head to effectively transfer energy to the metal component 2, the metallized ceramic substrate 1, and the PIN 3. Under pressure, friction is generated between the two metal surfaces, forming a fusion between the molecular layers. This directly manifests as extrusion deformation of the metal, making the weld stronger.

[0082] Since ultrasonic welding can achieve controllable deformation and the welding process is stable, its connection strength is significantly higher than that of solder paste reflow soldering, thereby effectively improving the reliability of the module.

[0083] Reference Figure 8 The implementation process of the injection molding packaging process of the present invention is as follows:

[0084] Step S1, using the welding head 91 of the ultrasonic welding device 9 to grab the power terminal 4, placing the power terminal 4 on the emitter 11 of the metallized ceramic substrate 1, and performing ultrasonic welding;

[0085] Step S2, the metal part 2 is loaded through the vibration plate;

[0086] Step S3: The welding head 91 grasps the metal part 2 through the vacuum adsorption hole 92 and places it on the emitter 11 of the metallized ceramic substrate 1 to perform ultrasonic welding;

[0087] Step S4, injecting the shell material into a preset mold to form a half-bridge structure;

[0088] Step S5, the PIN needle 3 is loaded through the vibration plate;

[0089] In step S6 , the welding head 91 absorbs and grabs the PIN 3 through the vacuum adsorption hole 92 and places it on the emitter 11 of the metallized ceramic substrate 1 to perform ultrasonic welding.

[0090] The above description is only a preferred embodiment of the present invention and does not limit the implementation method and protection scope of the present invention. For those skilled in the art, it should be aware that all solutions obtained by equivalent substitutions and obvious changes made using the description and illustrations of the present invention should be included in the protection scope of the present invention.

Claims

1. A power module with front-side pin-out, characterized in that: include, Metallized ceramic substrate; A metal member, the metal member comprising a flat welding bottom surface and a flat welding surface, wherein the welding bottom surface of the metal member is connected to the emitter of the metallized ceramic substrate; A PIN needle is vertically arranged on the welding surface of the metal part.

2. The power module with front-side pin outlet according to claim 1, characterized in that: The PIN needle is cylindrical and is a copper PIN needle.

3. The power module with front-side pin outlet according to claim 1, characterized in that: The metal piece is a copper column, and the width of the metal piece is 2 mm to 6 mm.

4. The power module with front-side pin outlet according to claim 1, characterized in that: The emitter of the metallized ceramic substrate is also connected to a power terminal.

5. The power module with front-side pin outlet according to claim 1, characterized in that: A semiconductor device is further provided on the emitter of the metallized ceramic substrate, and solder is provided between the semiconductor device and the emitter of the metallized ceramic substrate.

6. The power module with front-side pin outlet according to claim 5, characterized in that: The semiconductor device comprises at least a power chip and a diode. The semiconductor device is connected to the emitter of the metallized ceramic substrate via a metal bonding wire, and the semiconductor devices are connected to each other via the metal bonding wire.

7. The power module with front-side pin outlet according to claim 5, characterized in that: It also includes a heat dissipation substrate, which is arranged on the back side of the metallized ceramic substrate. The area of ​​the heat dissipation substrate is larger than that of the power module.

8. The power module with front-side pin outlet according to claim 7, characterized in that: It also includes a shell, which is arranged on the heat dissipation substrate, or the shell is connected to the outer side of the heat dissipation substrate.

9. The power module with front-side pin outlet according to claim 8, characterized in that: The housing is connected to the heat dissipation substrate to form an accommodating space. The metallized ceramic substrate, the metal part and the PIN needle are arranged in the accommodating space. One end of the PIN needle extends vertically upward out of the housing.

10. The power module with front-side pin outlet according to claim 7, characterized in that: The solder is provided between the heat dissipation substrate and the metallized ceramic substrate.

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