Anti-warping reflow soldering method for large-size injection molding module
By using magnetic cover plates and pressurized cover plates in patch tooling, combined with reflow soldering parameter debugging and quality inspection, the problem of large-size modules and substrate warping in traditional reflow soldering methods is solved, high-quality welding results are achieved, and high-reliability needs are met.
Patent Information
- Application Number
- CN202411902078.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2025-05-06
AI Technical Summary
Traditional reflow soldering methods cannot effectively suppress the warpage of the module and substrate during the welding of large-size injection molds, resulting in poor welding and affecting the quality and reliability of electronic products.
The anti-warming reflow soldering method is adopted, and the magnetic suction cover plate and pressurized cover plate are used in the patch tooling to apply stable pressure to suppress the warping of the module and substrate during the reflow soldering process, and the welding quality is ensured by debugging the reflow soldering parameters and quality detection.
It effectively suppresses the warpage of large-size injection molds and substrates during reflow soldering, improves welding quality and yield, and meets the high reliability needs in aerospace and military applications.
Smart Images
Figure CN119943687A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of semiconductor packaging, and in particular relates to an anti-warping reflow soldering method for a large-size injection molding module. Background Art
[0002] Reflow soldering technology is widely used in the electronics manufacturing industry to connect modules to module substrates by melting and re-solidifying the solder at high temperatures.
[0003] With the continuous development of information technology, artificial intelligence, autonomous driving, cloud computing, etc. usually need to analyze and process massive amounts of data, which puts forward new requirements for computing power. Traditional monolithic integrated circuits show bottlenecks such as increased complexity, longer design cycles, lower manufacturing yields, and surging costs. Chiplets and integrated chip technology combine multiple chips into a whole through advanced integration processes, greatly improving chip performance, reducing costs, and increasing yields, becoming one of the best ways to achieve development beyond Moore's Law.
[0004] Common core integration technologies include CoWoS (Chip on Wafer on Substrate), EMIB (Embedded MultiDie Interconnect Bridge), and ODI (Omni-Directional Interconnect). Taking CoWoS technology as an example, after interconnecting each core to the adapter board, it is necessary to perform injection molding on the entire core to form a large-size injection molding module, and then connect the injection molding module to the flip-chip substrate through reflow soldering. Compared with ordinary silicon-based chips, injection molding modules are larger in size, more complex in material structure, and have a prominent CTE (thermal expansion) mismatch phenomenon. At the same time, the corresponding substrate size is larger. During the reflow soldering process, due to the rapid change in temperature, large-size modules and large-size substrates are prone to warping and deformation, resulting in poor soldering of flip-chip modules, which in turn affects the quality and reliability of electronic products.
[0005] In the traditional reflow soldering method, the chip placement tooling and the reflow tooling are inconsistent, the circuit transfer operation is complicated, and the reflow tooling cannot limit the warping of the module and substrate in the Z-axis direction during the reflow process, which is prone to poor welding and cannot effectively inspect the interconnection quality. Therefore, there is an urgent need for a reflow soldering method for reflow soldering of large-size injection molding modules to suppress the warping of the module and substrate during the reflow process and achieve good welding of large-size injection molding modules. Summary of the invention
[0006] In order to solve the above-mentioned problems in the prior art, namely, in the traditional reflow soldering method, the circuit transfer operation is complicated, the warping of large-size modules and substrates in the Z-axis direction during the reflow soldering process and the resulting welding defects, the present invention provides an anti-warping reflow soldering method for large-size injection molding modules.
[0007] The technical solution of the present invention is:
[0008] A method for anti-warping reflow soldering of a large-size injection molding module, characterized by comprising the following steps:
[0009] Step S1: Use the patch tooling to achieve rough positioning of the flip-chip substrate on the flip-chip platform, improve the placement efficiency, and complete the placement;
[0010] Step S2: installing a magnetic cover plate and a pressure cover plate on the patch tooling to suppress the warping of the flip-chip substrate and the module;
[0011] Step S3: Debugging reflow soldering parameters to reduce flip-chip substrate warping and module warping during reflow soldering while ensuring reflow soldering quality;
[0012] Step S4: After the reflow soldering is completed, the reflow soldering quality is tested by using destructive testing and non-destructive testing.
[0013] As an optional technical solution, in step S1, the patch tooling includes a lower cover plate, a magnetic component, and a limiting cover plate. The lower cover plate is provided with an array hole on the front side, and the magnetic components are respectively arranged in the array holes. The outer contours of the lower cover plate and the limiting cover plate are adapted to each other, and a number of positioning holes are correspondingly provided. The lower cover plate and the limiting cover plate are fixedly connected through the positioning holes.
[0014] As an optional technical solution, the magnetic component is a cylindrical high-temperature resistant magnet with a withstand temperature of ≥400°C, a diameter of ≤8mm, and a height of ≤5mm. The magnetic poles of each magnetic component are in the same direction during installation; the lower cover plate is a rectangular aluminum alloy plate, and the array holes arranged on the front are all circular holes. The diameter of the circular holes is 1mm to 3mm larger than the diameter of the magnetic component, and the depth is 0.5mm to 2mm larger than the height of the magnetic component. The positioning holes are respectively arranged at the four corners of the lower cover plate.
[0015] As an optional technical solution, the limit cover plate is a rectangular aluminum alloy plate, and a limit groove is arranged at its center position. The length and width of the limit groove are 2mm to 4mm larger than the length and width of the flip-chip substrate, and the depth is 0.1mm to 0.3mm smaller than the thickness of the flip-chip substrate. Positioning pins are respectively arranged on both sides of the limit groove on the front side of the limit cover plate.
[0016] As an optional technical solution, in step S2, the magnetic cover plate is a rectangular iron cover plate, and its surface is treated with anti-oxidation and stress release. The contour of the magnetic cover plate is compatible with the limiting cover plate, and a hollow structure is arranged at the position corresponding to the flip-chip substrate. The length and width of the hollow structure are 5mm to 10mm larger than the module size and smaller than the flip-chip substrate size, and holes compatible with the positioning pins on the limiting cover plate are arranged on both sides of the hollow structure.
[0017] As an optional technical solution, in step S2, the pressure cover plate is a rectangular aluminum alloy plate, and its length and width dimensions are larger than the length and width dimensions of the module, and smaller than the length and width dimensions of the hollow structure of the magnetic cover plate. A rectangular groove is provided on the back of the pressure cover plate, and the length and width dimensions of the rectangular groove are 2mm to 5mm larger than the length and width dimensions of the module, and the depth of the rectangular groove is 0.3mm to 1.0mm smaller than the thickness of the module, and the average gravity of the pressure cover plate borne by each interconnected bump of the module is 1mg to 10mg.
[0018] As an optional technical solution, in step S3, the reflow soldering parameters include a heating rate, a cooling rate, and a peak temperature. The heating rate is ≤6°C / min, the cooling rate is ≤4°C / min, the peak temperature is more than 10°C greater than the melting point of the interconnect bump, and the reflow soldering temperature is based on the surface temperature of the interconnect bump.
[0019] As an optional technical solution, in step S4, the destructive inspection is a chip shear force test, (chip shear force (N) / number of chip bumps) ≥ 0.05N, and one module is randomly inspected from each batch of modules.
[0020] As an optional technical solution, in step S4, the non-destructive testing is chip X-ray testing, and the chip is qualified if there is no chip offset, no missing balls on the flip-chip solder joints, and no bridging; all modules in each batch of modules are subjected to non-destructive testing.
[0021] As an optional technical solution, step S1 includes: (a) placing the magnetic component in the circular hole array of the lower cover plate, connecting and locking the limit cover plate and the lower cover plate with bolts to complete the assembly of the patch tooling; (b) placing the flip-chip substrate in the limit slot of the patch tooling, and completing the mounting on the flip-chip platform of the device;
[0022] Step S2 includes: placing the magnetic cover plate on the upper layer of the patch tooling, the flip-chip substrate is located in the hollow structure of the magnetic cover plate, and placing the pressure cover plate on the upper layer of the chip to ensure that the center of the groove corresponds to the center of the chip;
[0023] Step S3 includes: (c) using the debugged reflow process curve to complete the reflow soldering between the chip and the substrate; (d) after the reflow is completed, removing the pressure cover plate and the magnetic cover plate in turn, and taking out the circuit;
[0024] Step S4 includes: after the batch is produced, the welding quality is inspected by chip shear force test and X-ray detection.
[0025] Beneficial effects of the present invention:
[0026] (1) The anti-warping reflow soldering method for large-size injection molding modules of the present invention can effectively solve the problem of poor welding caused by excessive warping of large-size injection molding modules and large-size substrates through patch tooling, magnetic cover plates and pressure cover plates. On the other hand, it can also simplify circuit transfer operations, improve welding yield and inspection effectiveness, and meet the high reliability requirements in aerospace and military application scenarios.
[0027] (2) The anti-warping reflow soldering method for large-sized injection molding modules of the present invention utilizes magnetic components and magnetic cover plates in patch tooling to apply stable pressure to large-sized modules and flip-chip substrates during reflow soldering, thereby suppressing the warping of large-sized modules and substrates caused by reflow soldering.
[0028] (3) The anti-warping reflow soldering method for large-size injection molding modules of the present invention utilizes a pressure cover plate to apply a certain pressure to the interconnection bumps of the module during reflow soldering, thereby further improving the quality of reflow soldering and improving the yield rate. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings:
[0030] Figure 1 The utility model is a schematic diagram of the tooling structure of the anti-warping reflow soldering method of the large-size injection molding module of the present invention.
[0031] Figure 2 The present invention is a schematic diagram of the chip tooling structure of the anti-warping reflow soldering method of the large-size injection molding module.
[0032] Figure 3 It is a schematic diagram of the magnetic cover structure of the anti-warping reflow soldering method of the large-size injection molding module of the present invention.
[0033] Figure 4 The present invention is a schematic diagram of a pressurized cover plate structure of an anti-warping reflow soldering method for a large-size injection molding module.
[0034] Figure 5 The present invention is a schematic flow chart of the anti-warping reflow soldering method for a large-size injection molding module.
[0035] Reference numerals:
[0036] 1-lower cover plate, 2-positioning hole, 3-circular hole array, 4-magnetic component, 5-limiting cover plate, 6-limiting groove, 7-positioning pin, 8-magnetic cover plate, 9-hollow structure, 10-positioning pin hole, 11-pressure cover plate, 12-bottom limiting groove, 13-flip substrate. DETAILED DESCRIPTION
[0037] The present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the relevant invention, rather than to limit the invention. It is also necessary to explain that, for ease of description, only the parts related to the relevant invention are shown in the accompanying drawings.
[0038] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.
[0039] The invention provides an anti-warping reflow soldering method for a large-size injection molding module.
[0040] Figure 1 The utility model is a schematic diagram of the tooling structure of the anti-warping reflow soldering method of the large-size injection molding module of the present invention.
[0041] Including patch tooling parts, such as Figure 2 The figure shows a schematic diagram of the structure of the patch tooling part, which includes a lower cover plate 1, which is a rectangular aluminum alloy plate with a circular hole array 3 on the front. The magnetic component 4 is a group of cylindrical high-temperature resistant magnets compatible with the circular hole array 3, and the magnetic components 4 are respectively arranged in the circular hole array 3.
[0042] The limit cover plate 5 is a rectangular aluminum alloy plate, and its outer contour size is consistent with that of the lower cover plate 1. The limit cover plate 5 is covered on the lower cover plate 1. Positioning holes 2 are correspondingly provided at the four corners of the lower cover plate 1 and the limit cover plate 5, and are positioned and fastened by bolts.
[0043] A limiting groove 6 is arranged at the center of the limiting cover plate 5. The limiting groove 6 is 2mm to 4mm larger than the length and width of the flip-chip substrate 13, and the depth is 0.1mm to 0.3mm smaller than the thickness of the flip-chip substrate 13. Positioning pins 7 are arranged on both sides of the limiting groove 6 on the front side of the limiting cover plate 5.
[0044] The flip-chip substrate 13 is embedded in the limiting groove 6 .
[0045] A magnetic cover plate 8 is arranged above the limit cover plate 5. Figure 3 As shown, the magnetic cover plate 8 is an iron rectangular plate, the surface of which must be treated with anti-oxidation and stress release, and the outer contour dimensions are consistent with the limit cover plate 5 and the lower cover plate 1.
[0046] A hollow structure 9 is provided at the center of the magnetic cover plate 8. The length and width of the hollow structure 9 are 5mm to 10mm larger than the module size, but smaller than the size of the flip-chip substrate 13. Positioning pin holes 10 that are compatible with the positioning pins 7 on the limiting cover plate 5 are provided on both sides of the hollow structure 9.
[0047] The magnetic cover plate 8 is covered on the limit cover plate 5, the positioning pin 7 is passed through the positioning pin hole 10 for positioning and fixing, the pressurized cover plate 11 is embedded in the hollow structure 9, and the pressurized cover plate 11 is covered on the flip-chip substrate 13, as shown in FIG. Figure 4 As shown, the pressure cover plate 11 is a rectangular aluminum alloy plate, whose length and width dimensions are larger than the length and width dimensions of the module, and smaller than the length and width dimensions of the hollow structure 9 of the magnetic cover plate 8. The bottom surface of the pressure cover plate 11 is provided with a bottom limiting groove 12, and the length and width dimensions of the bottom limiting groove 12 are 2mm to 5mm larger than the length and width dimensions of the module, and the depth of the groove is 0.3mm to 1.0mm smaller than the thickness of the module. The quality of the pressure cover plate 11 should ensure that the average pressure borne by each interconnected bump of the module is 1mg to 10mg.
[0048] like Figure 5 The flowchart of the anti-warping reflow soldering method of the large-size injection molding module of the present invention is shown. From the beginning to the end, it includes the steps S1 module mounting, S2 warping suppression, S3 reflow soldering, and S4 quality inspection.
[0049] Example
[0050] The substrate size is 50mm×50mm×3mm, the module size is 30mm×40mm×1mm, the melting point of the flip-chip bump is 280°C, and the number of flip-chip bumps is 5000.
[0051] The lower cover plate is made of aluminum alloy, and its overall dimensions are 150mm×150mm×5mm, which meets the requirements of the flip-chip platform of the flip-chip equipment. It is equipped with 4 positioning holes for installing screws. The 4 positioning holes are located at the four corners of the lower cover plate. A circular hole array is arranged on the front of the lower cover plate. The diameter of the circular hole is 5mm, the depth is 4.5mm, and the center distance between two adjacent circular holes is 15mm.
[0052] The magnetic component is an AlNiCo cylindrical magnet with a diameter of 4mm and a height of 4mm, and a temperature resistance of about 400°C. Each magnetic component corresponds to a mounting hole, and the magnetic pole direction should be kept consistent when the magnetic component is installed.
[0053] The limit cover is made of aluminum alloy, with an overall size of 150mm×150mm×4mm. There are 4 positioning holes on the back, which correspond to the lower cover. The screws are installed to fix the limit cover and the lower cover together. The limit cover is provided with a limit groove and a positioning pin on the front, which are used to place the flip-chip substrate and the magnetic cover for positioning. The length and width of the limit groove are 53mm×53mm, and the groove depth is 2.80mm lower than the thickness of the substrate. The positioning pin is a cylinder with a height of 8mm and a diameter of 5mm.
[0054] The magnetic cover is made of iron material, and has been leveled, anti-oxidation and stress-released. Its dimensions are 150mm×150mm×1.0mm, and it is equipped with a hollow structure and a positioning pin hole. The center position of the hollow structure is consistent with the center position of the module mounting on the substrate. The length and width of the hollow structure are 35mm×45mm, and the diameter of the positioning pin hole is 6mm.
[0055] The pressure cover is made of aluminum alloy, with an overall size of 33mm×43mm×2.6mm, a bottom limit groove size of 32mm×42mm×0.5mm, and a weight of 10g.
[0056] During use, first place the magnetic component array in the circular hole array, keep the magnetic pole directions of each component consistent, use screws to fix the lower cover, magnetic components and limit cover together through the positioning holes to complete the patch tooling assembly.
[0057] Place the flip-chip substrate into the limiting groove of the patch tooling, place the patch tooling on the flip-chip platform of the flip-chip equipment, and the patch tooling is adsorbed on the platform surface by magnetic force to achieve rough positioning of the flip-chip substrate, and then use the flip-chip equipment to complete chip mounting.
[0058] Transfer the patch tooling to the operating table, align the positioning pin hole of the magnetic cover plate with the positioning pin of the limiting cover plate to complete the placement of the magnetic cover plate, align the center of the bottom limiting groove of the pressurized cover plate with the center of the injection module to complete the assembly of the anti-warping reflow device.
[0059] The assembled reflow device was placed in a hot air reflow oven for reflow soldering. After the reflow process was debugged, the peak temperature of the reflow soldering was 305°C, the heating rate of the reflow curve was 3°C / min, the cooling rate of the reflow curve was 2°C / min, and the reflow soldering temperature was based on the surface temperature of the interconnection bumps. After the reflow was completed, the device was cooled to room temperature, and the pressure cover and magnetic cover were removed in turn to obtain a flip-chip soldering circuit that had been soldered.
[0060] A total of 100 flip-chip circuits were produced in this batch. After production, all 100 devices were subjected to X-ray inspection, and the inspection results were qualified, with no unqualified phenomena such as offset, missing balls, and bridging. One was selected for chip shear force test, and the chip shear force was measured to be 51.77kg, which meets the requirement of chip shear force (N) / chip bump number ≥ 0.05N. After inspection, the interconnection quality of the flip-chip circuits produced in this batch is qualified and meets the use requirements.
[0061] In summary, the anti-warping reflow method for large-size injection molding modules described in the present invention solves the problem of poor welding caused by excessive warping of large-size injection molding modules and large-size substrates, and can simplify circuit transfer operations, improve welding yield and inspection effectiveness, and meet the high reliability requirements in aerospace and military application scenarios. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has a high industrial utilization value.
[0062] In the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.
[0063] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0064] The term "comprise" or any other similar term is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus / device.
[0065] So far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.
Claims
1. A method for anti-warping reflow soldering of large-size injection molding modules, characterized in that The following steps are involved: Step S1: Use the patch tooling to achieve rough positioning of the flip-chip substrate on the flip-chip platform, improve the placement efficiency, and complete the placement; Step S2: installing a magnetic cover plate and a pressure cover plate on the patch tooling to suppress the warping of the flip-chip substrate and the module; Step S3: Debugging reflow soldering parameters to reduce flip-chip substrate warping and module warping during reflow soldering while ensuring reflow soldering quality; Step S4: After the reflow soldering is completed, the reflow soldering quality is tested by using destructive testing and non-destructive testing.
2. The anti-warping reflow soldering method for a large-size injection molding module according to claim 1, characterized in that: In step S1, the patch tooling includes a lower cover plate, a magnetic component, and a limiting cover plate. The lower cover plate is provided with an array hole on the front side, and the magnetic components are respectively arranged in the array holes. The outer contours of the lower cover plate and the limiting cover plate are adapted to each other, and a number of positioning holes are correspondingly provided. The lower cover plate and the limiting cover plate are fixedly connected through the positioning holes.
3. The anti-warping reflow soldering method for a large-size injection molding module according to claim 2, characterized in that: The magnetic component is a cylindrical high-temperature resistant magnet with a tolerance temperature of ≥400°C, a diameter of ≤8mm, and a height of ≤5mm. The magnetic poles of each magnetic component are in the same direction during installation; the lower cover plate is a rectangular aluminum alloy plate, and the array holes arranged on the front are all circular holes. The diameter of the circular holes is 1mm to 3mm larger than the diameter of the magnetic component, and the depth is 0.5mm to 2mm larger than the height of the magnetic component. The positioning holes are respectively arranged at the four corners of the lower cover plate.
4. The anti-warping reflow soldering method for a large-size injection molding module according to claim 2, characterized in that: The limit cover plate is a rectangular aluminum alloy plate, and a limit groove is arranged at its center position. The length and width of the limit groove are 2mm to 4mm larger than the length and width of the flip-chip substrate, and the depth is 0.1mm to 0.3mm smaller than the thickness of the flip-chip substrate. Positioning pins are arranged on both sides of the limit groove on the front side of the limit cover plate.
5. The anti-warping reflow soldering method for a large-size injection molding module according to claim 1, characterized in that: In step S2, the magnetic cover plate is a rectangular iron cover plate, and its surface is treated with anti-oxidation and stress release. The contour of the magnetic cover plate is compatible with the limiting cover plate, and a hollow structure is arranged at the position corresponding to the flip-chip substrate. The length and width of the hollow structure are 5mm to 10mm larger than the module size and smaller than the flip-chip substrate size, and holes compatible with the positioning pins on the limiting cover plate are arranged on both sides of the hollow structure.
6. The anti-warping reflow soldering method for a large-size injection molding module according to claim 1, characterized in that: In step S2, the pressure cover plate is a rectangular aluminum alloy plate, and its length and width are larger than the length and width of the module, and smaller than the length and width of the hollow structure of the magnetic cover plate. A rectangular groove is provided on the back of the pressure cover plate. The length and width of the rectangular groove are 2mm to 5mm larger than the length and width of the module, and the depth is 0.3mm to 1.0mm smaller than the thickness of the module. The average gravity of the pressure cover plate borne by each interconnected bump of the module is 1mg to 10mg.
7. The anti-warping reflow soldering method for a large-size injection molding module according to claim 1, characterized in that: In step S3, the reflow soldering parameters include a heating rate, a cooling rate, and a peak temperature. The heating rate is ≤6°C / min, the cooling rate is ≤4°C / min, the peak temperature is more than 10°C greater than the melting point of the interconnect bump, and the reflow soldering temperature is based on the surface temperature of the interconnect bump.
8. The anti-warping reflow soldering method for a large-size injection molding module according to claim 1, characterized in that: In step S4, the destructive test is a chip shear force test, (chip shear force (N) / chip bump number) ≥ 0.05N, and one module is randomly inspected from each batch of modules.
9. The anti-warping reflow soldering method for a large-size injection molding module according to claim 1, characterized in that: In step S4, the non-destructive testing is chip X-ray testing, and the chip is qualified if there is no chip offset, no missing balls on the flip-chip solder joints, and no bridging; all modules in each batch of modules are subjected to non-destructive testing.
10. The anti-warping reflow soldering method for a large-size injection molding module according to claim 1, characterized in that: Step S1 includes: (a) placing the magnetic component in the circular hole array of the lower cover plate, connecting and locking the limit cover plate and the lower cover plate with bolts to complete the assembly of the patch tooling; (b) placing the flip-chip substrate in the limit slot of the patch tooling, and completing the mounting on the flip-chip platform of the device; Step S2 includes: placing the magnetic cover plate on the upper layer of the patch tooling, the flip-chip substrate is located in the hollow structure of the magnetic cover plate, and placing the pressure cover plate on the upper layer of the chip to ensure that the center of the groove corresponds to the center of the chip; Step S3 includes: (c) using the debugged reflow process curve to complete the reflow soldering between the chip and the substrate; (d) after the reflow is completed, removing the pressure cover plate and the magnetic cover plate in turn, and taking out the circuit; Step S4 includes: after the batch is produced, the welding quality is inspected by chip shear force test and X-ray detection.