Surface-mounted bridge type rectifying device and manufacturing method thereof
By using a symmetrical mirror layout for the surface-mount bridge rectifier device design, the current carrying capacity and heat dissipation issues limited by package size are solved, achieving high current output and uniform heat dissipation, improving device reliability and lifespan, and making it suitable for high-density power modules.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 阳洪涛
- Filing Date
- 2026-01-19
- Publication Date
- 2026-04-21
Smart Images
Figure CN121908615A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the fields of semiconductor device packaging and power electronics technology, specifically to a surface-mount bridge rectifier device and its manufacturing method. Background Technology
[0002] Bridge rectifiers, as core power devices that convert alternating current (AC) to direct current (DC), are widely used in industrial power supplies, new energy vehicle charging stations, photovoltaic inverters, and communication equipment. With the development of power electronic equipment towards higher efficiency, higher power density, and miniaturization, higher requirements are being placed on the current capacity, heat dissipation performance, and package size of rectifier devices.
[0003] Currently, bridge rectifiers on the market are generally complex in structure. Due to the limitation of package size, larger chips cannot be used, resulting in limited current carrying capacity and difficulty in meeting the needs of high-power applications.
[0004] In addition, in terms of heat dissipation structure, traditional bridge rectifier heat dissipation mode mostly relies on lead wire heat dissipation or adds heat sinks to conduct through black glue. The heat dissipation path is long and the thermal resistance is high, which leads to a decrease in reliability under high temperature environment.
[0005] To address the aforementioned issues, there is an urgent need for a surface-mount bridge rectifier device and its manufacturing method to solve the problems associated with traditional methods. Summary of the Invention
[0006] The purpose of this invention is to provide a surface-mount bridge rectifier device and its manufacturing method, which achieves double current output and uniform heat dissipation through a symmetrical mirror layout, and is compatible with surface-mount and through-hole applications.
[0007] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A surface-mount bridge rectifier includes: a first metal base plate, a second metal base plate, a first diode chip, a second diode chip, a third diode chip, a fourth diode chip, a first placement substrate, and a second placement substrate. The first metal base plate and the second metal base plate serve as two AC input terminals of the rectifier. Both the first metal base plate and the second metal base plate are horizontally arranged. The first metal base plate has a first diode chip placed face-up and a third diode chip placed flip-chip in sequence in the horizontal direction. The second metal base plate has a second diode chip placed face-up and a fourth diode chip placed flip-chip in sequence in the horizontal direction. The first placement substrate is disposed on the top of the first diode and the second diode, and the second placement substrate is disposed on the top of the third diode and the fourth diode. The negative output terminal of the rectifier is disposed on the first placement substrate, and the positive output terminal of the rectifier is disposed on the second placement substrate.
[0008] Furthermore, the first and second diode chips, which are placed face-up, have their P-sides facing upwards, while the third and fourth diode chips, which are placed flip-chip, have their N-sides facing upwards.
[0009] Furthermore, the top right sides of the first metal base plate and the second metal base plate are respectively provided with bosses corresponding to the third diode chip and the fourth diode chip, and the P-side of the third diode chip and the fourth diode chip are connected to the bosses.
[0010] Furthermore, the first diode chip and the second diode chip are soldered to the first metal base plate and the second metal base plate respectively using solder pads or silver paste, and the third diode chip and the fourth diode chip are soldered to the boss respectively using solder pads, eutectic bonding or silver paste.
[0011] Furthermore, the first diode chip, the second diode chip, the third diode chip, and the fourth diode chip are connected to the first placement substrate and the second placement substrate respectively through soldering, frame, and wire bonding processes.
[0012] Furthermore, the surfaces of the first diode chip, the second diode chip, the third diode chip, and the fourth diode chip are coated with a plating layer, which is a TI, NI, AG, or AU metal layer.
[0013] Furthermore, both the first and second placement substrates are rectangular placement substrates, and the negative output terminal of the rectifier is provided in the middle of the first placement substrate, while the positive output terminal of the rectifier is provided in the middle of the second placement substrate.
[0014] Furthermore, both the first placement substrate and the second placement substrate are trapezoidal placement substrates, and the short side of the first placement substrate is provided with the negative output terminal of the rectifier, while the short side of the second placement substrate is provided with the positive output terminal of the rectifier.
[0015] The present invention also provides a method for manufacturing a surface-mount bridge rectifier device, applicable to the above-mentioned surface-mount bridge rectifier device, comprising: Step 1: Provide a horizontally arranged first metal base plate and a second metal base plate as two AC input terminals; Step 2: Sequentially fix the first diode chip placed face up and the third diode chip placed flip-chip in the horizontal direction of the first metal base plate; Sequentially fix the second diode chip placed face up and the fourth diode chip placed flip-chip in the horizontal direction of the second metal base plate. Step 3: A first placement substrate is disposed on top of the first diode chip and the second diode chip, and a second placement substrate is disposed on top of the third diode chip and the fourth diode chip; Step 4: Electrically connect the first diode chip and the second diode chip to the first placement substrate, respectively; and electrically connect the third diode chip and the fourth diode chip to the second placement substrate, respectively. Step 5: Form the negative output terminal of the device on the first placement substrate, and form the positive output terminal of the device on the second placement substrate.
[0016] In summary, the present invention has at least one of the following beneficial technical effects: 1. Achieving a balance between high current carrying capacity and space efficiency: By integrating four diode chips in a symmetrical combination of front-mounted and flip-chip placement onto two metal substrates and adopting a compact lateral layout, the device can accommodate larger chips within a unit package area, significantly improving the current output capability of a single device.
[0017] 2. Significantly Improved Heat Dissipation Uniformity and Reliability: The symmetrical chip layout and mirror-mount method allow the heat generated by the two rectifier units to be dissipated on both sides through two large-area metal base plates and the PCB board, forming an efficient and balanced heat dissipation path. This effectively avoids localized heat accumulation inside the device, significantly reducing the overall thermal resistance and maximum junction temperature. Uniform heat distribution improves the synchronization and stability of chip operation, reduces the risk of solder interface failure due to uneven thermal stress, and thus significantly enhances the reliability and lifespan of the device under long-term high power and high ambient temperature operation. Attached Figure Description
[0018] Figure 1 This is a front view of the overall structure of a surface-mount bridge rectifier device according to an embodiment of the present invention; Figure 2 This is a side view of the overall structure of a surface-mount bridge rectifier device according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the metal base plate structure; Figure 4 This is a schematic diagram illustrating the principle of symmetrical mirroring. Figure 5 This is a schematic diagram of the product structure; Figure 6 This is a top view of the overall structure of a surface-mount bridge rectifier device according to another embodiment of the present invention; Figure 7 This is a front view of the overall structure of a surface-mount bridge rectifier device according to another embodiment of the present invention.
[0019] Reference numerals: 1. First metal base plate; 2. Second metal base plate; 3. First diode chip; 4. Second diode chip; 5. Third diode chip; 6. Fourth diode chip; 7. First placement substrate; 8. Second placement substrate; 9. Solder sheet; 10. Boss. Detailed Implementation
[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.
[0021] This invention provides a surface-mount bridge rectifier device, comprising: a first metal base plate 1, a second metal base plate 2, a first diode chip 3, a second diode chip 4, a third diode chip 5, a fourth diode chip 6, a first placement substrate 7, and a second placement substrate 8. The first metal base plate 1 and the second metal base plate 2 serve as two AC input terminals of the rectifier device. Both the first metal base plate 1 and the second metal base plate 2 are horizontally arranged. The first metal base plate 1 has a first diode chip 3 placed face-up and a third diode chip 5 placed flip-chip in sequence in the horizontal direction. The second metal base plate 2 has a second diode chip 4 placed face-up and a fourth diode chip 6 placed flip-chip in sequence in the horizontal direction. The first placement substrate 7 is disposed on the top of the first diode and the second diode, and the second placement substrate 8 is disposed on the top of the third diode and the fourth diode. The first placement substrate 7 has a negative output terminal DC1 of the rectifier device, and the second placement substrate 8 has a positive output terminal DC2 of the rectifier device. The first placement substrate 7 and the second placement substrate 8 are the AC input terminals of the rectifier device.
[0022] The first diode chip 3 and the second diode chip 4, which are placed face up, have their P-sides facing up, while the third diode chip 5 and the fourth diode chip 6, which are placed in flip-chip configuration, have their N-sides facing up.
[0023] like Figure 3 As shown, the top right side of the first metal base plate 1 and the second metal base plate 2 are respectively provided with bosses 10 corresponding to the third diode chip 5 and the fourth diode chip 6, and the P-side of the third diode chip 5 and the fourth diode chip 6 are connected to the bosses 10.
[0024] The first diode chip 3 and the second diode chip 4 are soldered to the first metal base plate 1 and the second metal base plate 2 respectively by solder pads 9 or silver paste, and the third diode chip 5 and the fourth diode chip 6 are soldered to the boss 10 respectively by solder pads 9, eutectic or silver paste.
[0025] The first diode chip 3, the second diode chip 4, the third diode chip 5 and the fourth diode chip 6 are connected to the first placement substrate 7 and the second placement substrate 8 respectively through solder pads 9, frames and wire bonding processes.
[0026] The surfaces of the first diode chip 3, the second diode chip 4, the third diode chip 5, and the fourth diode chip 6 are coated with a metal layer, which may be a metal layer such as TI, NI, AG, or AU.
[0027] This invention provides two embodiments for placing a substrate, wherein: The first type is as follows: both the first placement substrate 7 and the second placement substrate 8 are rectangular placement substrates, and the negative output terminal DC1 of the rectifier is provided in the middle of the first placement substrate 7, and the positive output terminal DC2 of the rectifier is provided in the middle of the second placement substrate 8.
[0028] The second type is: both the first placement substrate 7 and the second placement substrate 8 are trapezoidal placement substrates, and the short side of the first placement substrate 7 is provided with the negative output terminal DC1 of the rectifier, and the short side of the second placement substrate 8 is provided with the positive output terminal DC2 of the rectifier.
[0029] like Figure 1 , Figure 2 , Figure 6 and Figure 7 As shown, it is a traditional frame welding structure, that is, the copper material used in the product is a copper alloy frame, and the solder is lead-containing solder paste and lead-free solder paste. It is welded at high temperature and has high reliability and high thermal conductivity.
[0030] Structurally, a bottom eutectic process can be used, and a wire bonding process can be used on the front side. From a cost perspective, an AG-SN system can be used, with the surface of the substrate treated with silver alloy or pure silver, and the back of the chip plated with tin or gold.
[0031] This invention provides the principle of structural mirroring, specifically as follows: Figure 4 and Figure 5 As shown, in applications, rectifier devices can be mounted face-to-face to double the input and output power. Without increasing the PCB layout space, this can effectively reduce defects caused by temperature asymmetry and other factors, and reduce power loss. By employing a symmetrical mirror layout, the two rectifier units share a common heat dissipation path, significantly improving the uniformity of heat distribution and preventing performance degradation caused by localized overheating. This design balances electrical performance and heat dissipation efficiency, making it suitable for high-density power modules. It achieves double the current output capacity within the same space while reducing the overall system thermal resistance and improving the long-term reliability of the product. Optimizing the distribution density of the metal connection structure further reduces impedance loss in the current path, improving conduction efficiency. The layout of the first placement substrate 7 and the second placement substrate 8 adopts a symmetrical and equal-length design, ensuring balanced current distribution when the two rectifier units operate in parallel, avoiding thermal offset caused by differences in wiring. The geometry of the solder pad 9 has been simulated and iterated to achieve a balance between maximum contact area and minimum thermal stress, enhancing interface bonding strength. The entire structure exhibits excellent reliability in reflow soldering processes, making it suitable for automated mounting lines and meeting the long-term stable operation requirements in industrial environments.
[0032] This invention can use a silver paste process, and the product can be completely lead-free, breaking through the barrier that existing bridge rectifiers inevitably contain lead.
[0033] Setting the rectifier device to have pins on the bottom allows for complete contact between the product and the PCBA and increases the contact area of the metal base plate. Due to the simplification of the structure, the product can use a larger chip per unit area to achieve a higher current carrying capacity.
[0034] refer to Figure 5 The green part is the PCB, such as Figure 5 In the left image, the blue section shows two bridge rectifiers facing each other, positioned on either side of the PCB. Due to the product's unique structure, the AC and DC sections can be mirrored and overlapped. In applications, this reduces the current consumption of individual components, minimizes power loss within a limited space, and improves heat dissipation, thus addressing the challenge of lowering the product's temperature. refer to Figure 5 The unique layout of the bottom pins AC, DC1, DC2, and AC allows for symmetrical connection during use, achieving a mirrored application. While it can be used for surface mounting, it can also achieve the effect of a plug-in bridge rectifier through PCBA insertion board mode, and can achieve a capacity of over 100A.
[0035] This invention effectively improves the product's heat dissipation performance and current carrying capacity, while being compatible with both surface mount and through-hole mounting methods, significantly enhancing the flexibility of application scenarios. By optimizing the internal layout and connection process, the product achieves high reliability while maintaining miniaturization, meeting the needs of high-current and high-efficiency applications. The symmetrical structural design facilitates automated placement and reflow soldering, improving production efficiency and reducing assembly costs. Optimization of chip layout and conductive paths significantly reduces parasitic inductance and resistive losses, further improving overall conversion efficiency. It maintains stable performance even in high-temperature and high-humidity environments, making it suitable for demanding applications such as industrial power supplies, new energy vehicle charging piles, and photovoltaic inverters. With high reliability and long lifespan, it meets the development needs of future high-efficiency energy conversion systems. The product achieves double-sided heat dissipation through a tight fit between the bottom metal plate and the PCB, significantly reducing thermal resistance and improving long-term operational stability. Combined with lead-free processes and the application of environmentally friendly materials, it complies with RoHS and REACH environmental standards, meeting global market access requirements. The welding structure utilizes a eutectic bonding and wire bonding process, optimizing the product assembly process. The diode chip surface plating uses TI, NI, AG, or AU metal layers to ensure excellent conductivity and oxidation resistance, effectively improving interface stability and long-term reliability. Precise control of eutectic temperature and pressure parameters achieves a low-voidity connection between the chip and the substrate, further enhancing heat dissipation efficiency. The TI, NI, AG, or AU layers maintain excellent adhesion and conductivity even under high-temperature reflow conditions, preventing metal migration and oxidation failure, ensuring stable product performance under continuous high current and thermal cycling conditions, meeting the stringent requirements of automotive-grade applications. The product supports a wide temperature range (-55℃ to +175℃) and possesses excellent thermal shock resistance, making it suitable for complex thermal stress environments. Through an integrated multi-chip parallel architecture and low-inductance lead layout, current distribution is balanced, improving overall reliability.
[0036] The present invention also provides a method for manufacturing a surface-mount bridge rectifier device, applicable to the above-mentioned surface-mount bridge rectifier device, comprising: Step 1: Provide a horizontally arranged first metal base plate and a second metal base plate as two AC input terminals; Step 2: Sequentially fix the first diode chip placed face up and the third diode chip placed flip-chip in the horizontal direction of the first metal base plate; Sequentially fix the second diode chip placed face up and the fourth diode chip placed flip-chip in the horizontal direction of the second metal base plate. Step 3: A first placement substrate is disposed on top of the first diode chip and the second diode chip, and a second placement substrate is disposed on top of the third diode chip and the fourth diode chip; Step 4: Electrically connect the first diode chip and the second diode chip to the first placement substrate, respectively; and electrically connect the third diode chip and the fourth diode chip to the second placement substrate, respectively. Step 5: Form the negative output terminal of the device on the first placement substrate, and form the positive output terminal of the device on the second placement substrate.
[0037] Embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0038] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.
[0039] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.
[0040] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.
[0041] Contents not described in detail in this specification are prior art known to those skilled in the art. It is hereby indicated that the above description is intended to help those skilled in the art understand this invention, but does not limit the scope of protection of this invention. Any equivalent substitutions, modifications, improvements, or simplifications of the above descriptions that do not depart from the essential content of this invention fall within the scope of protection of this invention.
Claims
1. A surface-mount bridge rectifier device, characterized in that, include: The system comprises a first metal base plate, a second metal base plate, a first diode chip, a second diode chip, a third diode chip, a fourth diode chip, a first placement substrate, and a second placement substrate. The first and second metal base plates serve as two AC input terminals of the rectifier. Both the first and second metal base plates are horizontally arranged. The first metal base plate has a first diode chip placed face-up and a third diode chip placed flip-chip in sequence in the horizontal direction. The second metal base plate has a second diode chip placed face-up and a fourth diode chip placed flip-chip in sequence in the horizontal direction. The first placement substrate is placed on top of the first and second diodes, and the second placement substrate is placed on top of the third and fourth diodes. The negative output terminal of the rectifier is provided on the first placement substrate, and the positive output terminal of the rectifier is provided on the second placement substrate.
2. The surface-mount bridge rectifier device according to claim 1, characterized in that, The first and second diode chips are placed face up with their P-sides facing up, while the third and fourth diode chips are placed face down with their N-sides facing up.
3. The surface-mount bridge rectifier device according to claim 2, characterized in that, The top right side of the first metal base plate and the second metal base plate are respectively provided with bosses corresponding to the third diode chip and the fourth diode chip, and the P-side of the third diode chip and the fourth diode chip are connected to the bosses.
4. A surface-mount bridge rectifier device according to claim 3, characterized in that, The first diode chip and the second diode chip are soldered to the first metal base plate and the second metal base plate respectively by solder pads or silver paste, and the third diode chip and the fourth diode chip are soldered to the boss respectively by solder pads, eutectic bonding or silver paste.
5. A surface-mount bridge rectifier device according to claim 4, characterized in that, The first diode chip, the second diode chip, the third diode chip, and the fourth diode chip are connected to the first placement substrate and the second placement substrate respectively through soldering, frame, and wire bonding processes.
6. A surface-mount bridge rectifier device according to claim 5, characterized in that, The surfaces of the first diode chip, the second diode chip, the third diode chip, and the fourth diode chip are coated with a plating layer, which is a TI, NI, AG, or AU metal layer.
7. A surface-mount bridge rectifier device according to claim 6, characterized in that, Both the first and second placement substrates are rectangular placement substrates, and the negative output terminal of the rectifier is provided in the middle of the first placement substrate, while the positive output terminal of the rectifier is provided in the middle of the second placement substrate.
8. A surface-mount bridge rectifier device according to claim 6, characterized in that, Both the first and second placement substrates are trapezoidal placement substrates, and the short side of the first placement substrate is provided with the negative output terminal of the rectifier, while the short side of the second placement substrate is provided with the positive output terminal of the rectifier.
9. A method for manufacturing a surface-mount bridge rectifier, applied to the surface-mount bridge rectifier according to any one of claims 1-8, characterized in that, include: Step 1: Provide a horizontally arranged first metal base plate and a second metal base plate as two AC input terminals; Step 2: Sequentially fix the first diode chip placed face up and the third diode chip placed flip-chip in the horizontal direction of the first metal base plate; Sequentially fix the second diode chip placed face up and the fourth diode chip placed flip-chip in the horizontal direction of the second metal base plate. Step 3: A first placement substrate is disposed on top of the first diode chip and the second diode chip, and a second placement substrate is disposed on top of the third diode chip and the fourth diode chip; Step 4: Electrically connect the first diode chip and the second diode chip to the first placement substrate, respectively; and electrically connect the third diode chip and the fourth diode chip to the second placement substrate, respectively. Step 5: Form the negative output terminal of the device on the first placement substrate, and form the positive output terminal of the device on the second placement substrate.