Parameter-controllable welding device capable of preparing TLP welding layers in batches

Abstract

The invention discloses a welding device with controllable parameters and capable of preparing TLP welding layers in batches, and relates to the field of microelectronic packaging. The device comprises a supporting foot stool, a horizontal carrying plate, a combined structure of a horizontal sliding table and a mounting plate, a pressing plate, a magnet, a connecting rod, a pressure sensor, a lifting mechanism adapter plate, a lifting mechanism conveying belt structure, a motor, a lifting mechanism transmission shaft and a lifting mechanism supporting frame. And the motor equipment is controlled to realize vertical lifting of the pressing plate, so that welding pressure is applied. Accurate butt joint of the mask plate and the pressing plate is achieved by adjusting the horizontal sliding table, the welding pressure can be accurately controlled through cooperation with the pressure sensor, the temperature of the heating piece can be accurately controlled through the temperature control device, and accurate control over the welding pressure and temperature is achieved. And the TLP welding spots with stable and reliable quality can be prepared in batches in cooperation with a multi-slot customized mask.

Description

Technical Field

[0001] This product belongs to the field of microelectronic packaging, and particularly relates to a welding device capable of controlling parameters and batch-producing TLP welding layers. Background Art

[0002] The transient liquid phase (TLP) diffusion bonding technology has now been widely used in the packaging and connection of third-generation semiconductor power devices. The principle of the TLP bonding technology is to utilize the solid-liquid interdiffusion reaction between the molten intermediate solder and the two high-melting-point base materials under the temperature condition below the melting point of the solder and above the melting point of the base material to prepare a welding joint with high-melting-point all intermetallic compounds. TLP solder joints have advantages such as good high-temperature service performance, high strength, and low cost, and are particularly suitable for power chip packaging scenarios with high requirements for high-temperature performance, capable of meeting the requirements of "low-temperature connection and high-temperature service". At present, there have been a large number of related studies on TLP technology and the reliability of its solder joints. However, at present, most existing TLP welding devices are limited to the experimental stage, and many key process problems still need to be solved urgently. The existing TLP welding equipment has the following main problems in practical applications: 1) Process parameter control problem: Traditional TLP welding devices often cannot accurately control parameters such as pressure, temperature, and welding time during the welding process, and cannot stably and reliably prepare TLP solder joints with uniform performance; 2) Liquid solder waste problem: During the TLP welding process, the molten liquid solder easily flows out of the weld seam, which not only causes waste of welding materials but also causes welding defects, thus affecting the appearance and performance of the joint; 3) Heating device to be optimized problem: Traditional TLP welding devices use an external large oven for heating, with low heating efficiency, complex device, and high cost. Therefore, developing a new type of TLP welding device that can accurately control key process parameters such as pressure and temperature during the TLP welding process and has a simple heating device and low cost is of great significance for improving the reliability of TLP solder joints and promoting the large-scale application of TLP bonding technology.

[0003] This patent proposes a new type of TLP welding device that can accurately control the pressure during the TLP welding process and has a simple heating device, aiming to promote the development of TLP technology and provide a stable and reliable TLP welding solution for industrial production. Summary of the Invention

[0004] To solve the above problems, the present invention provides a welding device capable of controlling parameters and batch-producing TLP welding layers, which can accurately control parameters such as pressure, temperature, and welding time during the welding process, effectively avoid the overflow of molten liquid solder, and can batch-produce TLP solder joints with uniform performance stably and reliably.

[0005] A welding device for controllable parameters and batch preparation of TLP welding layers, characterized in that it includes adjustable-height support feet (1), a horizontal carrier plate (2), a combined structure of a horizontal sliding table and a mounting plate (3), a pressure plate (4); a magnet (5), a connecting rod (6), a pressure sensor (7), a lifting mechanism adapter plate (8), a lifting mechanism conveyor belt structure (9), a motor (10), a lifting mechanism transmission shaft (11), and a lifting mechanism support frame (12).

[0006] Assume that the plane where the horizontal carrier plate (2) is located is the horizontal direction, and the vertical direction of the horizontal carrier plate is the vertical direction. In this device, four support feet (1) are installed at the bottom of the horizontal carrier plate (2) for load-bearing, and the support feet (1) can adjust the height in the vertical direction through adjusting nuts and bolts to meet different requirements; a lifting mechanism and a combined structure of a horizontal sliding table and a mounting plate (3) are respectively installed on the horizontal carrier plate (2). In the lifting mechanism, the steel support frame (12) serves as the main load-bearing part to provide stable support for the lifting structure. A motor (10) and a vertical transmission shaft (11) are installed on the support frame (12). The motor (10) and the vertical transmission shaft (11) are connected through a conveyor belt structure (9); one end of the adapter plate (8) with a horizontal structure is installed on the transmission shaft (11), and the two are connected and driven through internal and external threads. The transmission shaft (11) has external threads, and the adapter plate (8) has an internal thread through hole; when the conveyor belt (9) rotates forward or backward, it drives the transmission shaft (11) to rotate clockwise or counterclockwise, and is driven through a threaded structure to move the adapter plate (8) vertically upward or downward; while the adapter plate (8) is connected to the transmission shaft (11), the support frame (12) is also provided with a vertical slide rail to limit the adapter plate (8), so that the adapter plate (8) can only move in the vertical direction, and it is ensured that the adapter plate will not rotate in the horizontal direction due to the transmission of the threaded structure; the other end of the adapter plate (8) is successively installed with a pressure sensor (7), a connecting rod (6), a magnet (5), and a pressure plate (4) from top to bottom along the vertical direction. Among them, the magnet (5) connects the pressure plate (4) through magnetic attraction; the adapter plate (8) limits the pressure plate (4) to only move along the vertical direction, ensuring uniform pressure is applied to the upper surface of the chip.

[0007] For the combined structure (3) of the horizontal slide and the mounting plate, the structure from top to bottom is the mounting plate (13) and the horizontal slide in sequence, and the two are connected by screws (27); a groove with the same length and width as the mask plate (14) is made above the mounting plate (13), wherein the mask plate (14) is made with a plurality of through-hole arrays, each through-hole corresponding to a chip and a substrate to be welded, and each through-hole is made according to the length and width of the chip and the substrate to be welded. A pressing block (15) is provided above the mask plate (14), and the lower surface of the pressing block (15) has protrusions, and the protrusions correspond to and match the through-holes of the mask plate (14) one by one. A slot is provided on one side of the mounting plate (13) for inserting the heating sheet (26) from the slot to the bottom of the groove of the mounting plate (13). The heating sheet fixing plate (17) is used to limit the horizontal displacement of the heating sheet (26). During use, the heating sheet fixing plate (17) is inserted into the side slots (13) of the mounting plate on both sides of the heating sheet (26), and then fixed with screws (16) from above the slot.

[0008] The horizontal slide can enable the mounting plate (13) to achieve high-precision displacement in the horizontal direction. A commercially available structure that can precisely control the left and right horizontal displacement can be adopted. For example, the horizontal slide includes a Y-axis slide (18) above and an X-axis slide (19) below. The Y-axis slide (18) and the X-axis slide (19) are respectively fixed with screws (23) and screws (20). The Y-axis slide (18) is equipped with a first screw rod (25), and the X-axis slide (19) is equipped with a second screw rod (21). The displacement of the horizontal slide in the X-axis and Y-axis directions can be adjusted by adjusting the first screw rod (25) and the second screw rod (21) respectively. The two slides are connected by a slide connecting plate (22), and the whole horizontal slide is connected to the mounting plate (13) above through a threaded connecting plate (24).

[0009] In addition, the motor (10) of the lifting mechanism is equipped with a dedicated numerical control system, which uses an external device to synchronously read the value of the pressure sensor (7) and controls the lifting of the motor through the numerical control system, so as to achieve precise control of the pressure.

[0010] The welding method applicable to the above-mentioned TLP welding device is characterized by including the following steps:

[0011] Step 1: Provide a chip and a substrate, which are respectively located on both sides of the intermediate solder. Prepare a first metal pad on the surface of the chip and a second metal pad on the surface of the substrate; in addition, according to needs, a first metal coating and a second metal coating can be selectively prepared on the surfaces of the first metal pad and the second metal pad respectively;

[0012] The substrate is a PCB substrate or a ceramic substrate;

[0013] The first metal pad and the second metal pad are made of the same material, both being Cu;

[0014] The first metal plating layer and the second metal plating layer are made of the same material, such as one of Ni, Ni-P, Ni-W-P, Co, Co-P, Co-W, Co-W-P, Fe, Ni-Fe-P;

[0015] The first metal plating layer and the second metal plating layer play a role in improving the wettability of the pad surface and diffusion barrier;

[0016] Step 2: Provide a mounting plate (13), a heating sheet (26) and a mask plate (14). First, connect the mounting plate (13) to the high-precision horizontal sliding table below. Then, insert the heating sheet (26) into the slot on the side of the mounting plate (13). Next, insert the heating sheet fixing plate (17) into the left and right sides of the mounting plate slot, leaving a certain space in the middle of the slot for the wire of the heating sheet. The screw (16) restricts the displacement of the heating sheet fixing plate (17) from above, thereby fixing the heating sheet (26). The heating sheet (26) is connected to an external high-precision temperature controller to be able to monitor the average temperature of the heating sheet in real time. Finally, place the mask plate (14) vertically into the groove above the mounting plate (13) and closely fit it with the heating sheet (26). Before placing the mask plate (14), a thin layer of thermal conductive silicone grease needs to be coated on the surface of the heating sheet (26) to ensure that the mask plate is in close contact with the heating sheet and is evenly heated, thereby improving the heat conduction efficiency. In addition, the mask plate can be customized with through slots of corresponding sizes according to the sizes of the chip and the substrate;

[0017] The side of the mounting plate has a slot with the same length and height as the heating sheet;

[0018] The upper part of the mounting plate has a groove with the same length and width as the mask plate;

[0019] The length and width of the heating sheet are the same as those of the mask plate;

[0020] The material of the heating sheet is silicone fiberglass or ceramic or aluminum alloy;

[0021] The mask plate has through slots with the same length and width as the chip and the substrate;

[0022] Step 3: First, sequentially place the substrate, the intermediate solder, and the chip into the through-holes of the mask plate to form a combined structure with the substrate / the first metal pad / the intermediate solder / the second metal pad / the chip from bottom to top. Place the pressing block (15) on and closely fit it to the upper surface of the chip. Then, adjust the horizontal slide under the mounting plate (13) so that the groove of the mounting plate (13) is aligned with the pressing plate (4) of the lifting mechanism in the vertical direction. Control the motor (10) to slowly lower the pressing plate until the pressing plate (4) enters the groove of the mounting plate (13) and is in close contact with the pressing block (15). The pressing plate (4) conducts the pressure to the upper surface of the chip through the pressing block (15), thereby realizing the pressurization process of the above combined structure. Conversely, control the motor to slowly raise the pressing plate to reduce the pressure;

[0023] The intermediate solder is one of pure Sn, Sn-Cu, Sn-Ag, Sn-Ag-Cu, Sn-Bi, Sn-Pb, Sn-Zn, Sn-In, Sn-Sb, Sn-Au;

[0024] The intermediate solder can be prepared on the surfaces of the first metal pad and the second metal pad through a deposition process, or inserted between the first metal pad and the second metal pad in the form of a solder sheet;

[0025] The pressing plate has the same length and width as the groove of the mounting plate and the mask plate;

[0026] Step 4: After the pressing plate (4) is in close contact with the pressing block (15), use the pressure sensor (7) to read the accurate pressure value, and the pressure value can be adjusted according to requirements. Then, set the heating temperature on the external temperature controller. The heating sheet is in close contact with the substrate through thermal conductive silicone grease, realizing high-efficiency heat transfer and ensuring that the entire combined structure is evenly heated during the welding process. When the heating sheet reaches the required temperature, welding starts, and it is kept at the set temperature for a period of time to allow sufficient atomic diffusion between the molten intermediate solder and the first metal pad and the second metal pad;

[0027] The heating temperature is the temperature of the entire heating sheet; the heating temperature range is 200°C to 380°C;

[0028] The combined structure is substrate / first metal pad / intermediate solder / second metal pad / chip;

[0029] Step 5: After insulating for the required time, stop heating to stop welding. Control the motor to slowly raise the pressing plate. The magnet above the pressing plate simultaneously adsorbs the pressing plate and the pressing block, and takes away all the pressing blocks at the same time. At this time, after sufficient atomic diffusion, a structure of substrate / first metal pad / intermetallic compound / second metal pad / chip is formed, and finally, the structure with all intermetallic compound solder joints is taken out;

[0030] The intermetallic compound is one of Cu-Sn, Ni-Sn, Co-Sn, and Fe-Sn intermetallic compounds.

[0031] Advantages of the present invention:

[0032] (1) Improved welding quality: The device can precisely control key TLP welding parameters such as welding pressure and temperature, and can batch and stably prepare TLP solder joints with uniform performance, thus improving welding quality.

[0033] (2) Reduced production cost: By precisely controlling the welding pressure, it avoids waste caused by molten solder overflow, improves the utilization rate of solder, and reduces production costs. At the same time, the present invention uses a heating sheet with low cost and high heating efficiency. Compared with the traditional high-cost and complex external constant temperature box, it not only simplifies the heating device but also effectively saves costs. The present invention can batch produce stable and reliable TLP solder joints, improve the yield and efficiency of power chip packaging, and thus reduce large-scale production costs.

[0034] (3) Improved heating efficiency: Compared with the overall heating method of traditional ovens, the present invention has the advantages of a simple heating device and high heating efficiency, and has good feasibility.

[0035] (4) Wide applicability of the device: The device has the advantages of simple structure, high heating efficiency, and low cost. It can not only be used for large-scale production of power chips but also for research and industrial production in other fields based on TLP technology.

[0036] A welding device for controllable parameters and batch preparation of TLP welding layers according to the present invention has the above technical features and advantages, overcomes the deficiencies in the prior art, and is expected to promote the further development of TLP connection technology and welding devices in research and industrial production. Description of the Drawings

[0037] Figure 1 Isometric view of the overall structure of the welding device;

[0038] Figure 2 Side view of the overall structure of the welding device;

[0039] Figure 3 Sectional view of the threaded connection structure between the adapter plate and the transmission shaft;

[0040] Figure 4 Schematic diagram of the horizontal slide table and the mounting plate;

[0041] Figure 5 Schematic diagram of the TLP welding process applicable to the present invention;

[0042] In the figure: 1. Adjustable-height support leg; 2. Horizontal loading plate; 3. Combined structure of horizontal slide and welding fixture; 4. Pressing plate; 5. Magnet; 6. Connecting rod; 7. Pressure sensor; 8. Adapter plate of lifting mechanism; 9. Cover plate of lifting mechanism transmission device; 10. Motor; 11. Transmission shaft of lifting mechanism; 12. Support frame of lifting mechanism; 13. Mounting plate; 14. Mask plate; 15. Pressing block; 16. Screw for fixing plate; 17. Fixed plate for heating sheet; 18. First horizontal slide; 19. Second horizontal slide; 20. Fixed screw for second horizontal slide; 21. Screw rod of second horizontal slide; 22. Slide connecting plate; 23. Fixed screw for first horizontal slide; 24. Threaded connecting plate; 25. Screw rod of first horizontal slide; 26. Heating sheet; 27. Connecting screw; 28. Cross-sectional structure of sample before TLP welding; 29. Cross-sectional structure of TLP solder joint. Detailed implementation mode

[0043] The present invention will be further described below in conjunction with specific drawings and embodiments. However, the present invention is not limited to the following embodiments.

[0044] A welding device with controllable parameters and capable of batch preparation of TLP welding layer, characterized in that it includes a combined structure of a high-precision horizontal slide and a mounting plate and a lifting mechanism. The lifting mechanism can control the vertical movement of the pressing plate, and the high-precision horizontal slide can accurately control the horizontal displacement of the mounting plate. Through the precise cooperation of the mounting plate, heating sheet and mask plate, the pairwise docking of the substrate and the chip can be ensured. The addition of a pressure sensor and a temperature controller ensures the precise control of pressure and temperature during the TLP welding process.

[0045] As Figure 1 and Figure 2As shown in the figure, it is assumed that the direction of the plane where the horizontal carrier plate (2) is located is the horizontal direction, and the vertical direction of the horizontal carrier plate is the vertical direction. In this device, four support feet (1) are installed at the bottom of the horizontal carrier plate (2) for load bearing, and the support feet (1) can adjust the height in the vertical direction through adjusting nut bolts to meet different requirements; a lifting mechanism and a combined structure of a horizontal slide table and a mounting plate (3) are respectively installed on the horizontal carrier plate (2). In the lifting mechanism, the steel structure support frame (12) serves as the main load-bearing part to provide stable support for the lifting structure. A transmission shaft (11) and a motor (10) are installed on the support frame (12), and they are connected through a conveyor belt structure (9) to achieve the lifting operation. One end of the adapter plate (8) is installed on the transmission shaft (11), and they are connected and driven through internal and external threads. The transmission shaft (11) is processed with external threads, and the adapter plate (8) is processed with an internal thread through hole. When the conveyor belt (9) rotates forward or backward, it drives the transmission shaft (11) to rotate clockwise or counterclockwise, and is driven through the thread structure to make the adapter plate (8) move vertically upward or downward. While the adapter plate (8) is connected to the transmission shaft (11), it is also connected to the support frame (12) through a vertical slide rail on one side of the support frame, which not only restricts the adapter plate (8) to move only in the vertical direction but also ensures that the adapter plate does not rotate in the horizontal direction due to the transmission of the thread structure. The other end of the adapter plate (8) is successively installed with a pressure sensor (7), a connecting rod (6), a magnet (5), and a pressing plate (4) from top to bottom in the vertical direction, and the magnet connects the pressing plate (4) through magnetic attraction. The adapter plate (8) restricts the pressing plate (4) to move only along the vertical direction to ensure uniform pressure is applied to the upper surface of the chip.

[0046] For the combined structure of the horizontal slide table and the mounting plate (3), from top to bottom, this structure is successively a mounting plate (13) and a horizontal slide table, and they are connected through screws (27). A groove with the same length and width as the mask plate (14) is made above the mounting plate (13). Multiple through-hole arrays are made on the mask plate (14), and each through hole corresponds to a chip and a substrate to be welded. Each through hole is made according to the length and width of the chip and the substrate to be welded. A pressing block (15) is provided above the mask plate (14), and the lower surface of the pressing block (15) has protrusions, and the protrusions correspond to the through holes of the mask plate (14) one by one. A slot is provided on one side of the mounting plate (13) for inserting the heating sheet (26) to the bottom of the groove of the mounting plate (13). The heating sheet (17) fixing plate is used to restrict the horizontal displacement of the heating sheet (26). During use, it only needs to be inserted into the side slot of the mounting plate (13) and fixed with screws (16).

[0047] The horizontal slide table can achieve high-precision displacement of the mounting plate (13) in the horizontal direction. The horizontal slide table includes a Y-axis slide table (18) above and an X-axis slide table (19) below. The slide table (18) and the slide table (19) are fixed using screws (23) and screws (20) respectively. The displacement of the horizontal slide table in the X-axis and Y-axis directions can be adjusted by the lead screw (25) and the lead screw (21) respectively. The two slide tables are connected by a slide table connecting plate (22). The entire horizontal slide table is connected to the upper mounting plate (13) through a threaded connecting plate (24). In addition, the motor (10) of the lifting mechanism is equipped with a dedicated numerical control system, which uses an external device to synchronously read the value of the pressure sensor (7) and controls the lifting of the motor through the numerical control system, thereby achieving precise control of the pressure.

[0048] As Figure 5 shown in, the welding method applicable to the above TLP welding device includes the following steps:

[0049] Step 1: Provide 8 power chips and 8 ceramic substrates, which are located on both sides of the pure Sn solder in the intermediate layer. Pure Cu pads are prepared on the surfaces of the chips and the ceramic substrates respectively. A metal coating can be selectively prepared on the surface of the Cu pads through a deposition process. The metal coating can improve the wettability between the surface of the Cu pad and the Sn solder and play a role in blocking the diffusion of Cu and Sn atoms, preventing the formation of brittle Cu-Sn intermetallic compounds, which is beneficial to improving the mechanical properties of the joint;

[0050] Step 2: As Figure 5 (a) and Figure 5 (b) shown, provide a mounting plate, a heating sheet and a mask plate. Grooves with the same length and height as the heating sheet are machined on the side of the mounting plate, and grooves with the same length and width as the mask plate are machined at the upper end of the mounting plate; an alumina ceramic heating sheet is used, and its length and width are the same as those of the mask plate; the mask plate is customized with 8 through holes of the same size according to the sizes of the chips and the substrates; first, connect the mounting plate to the lower horizontal slide table with screws, then insert the heating sheet into the slot on the side of the mounting plate, and then insert the heating sheet fixing plate into the left and right sides of the mounting plate slot. A certain space is reserved in the middle of the slot for the wires of the heating sheet. The screws limit the displacement of the heating sheet fixing plate, thereby fixing the heating sheet; the heating sheet is connected to an external high-precision temperature controller, which can monitor the average temperature of the heating sheet in real time. Finally, place the mask plate vertically into the groove above the mounting plate and fit it tightly with the heating sheet. Before placing the mask plate, a thin layer of thermal conductive silicone grease needs to be coated on the surface of the heating sheet to ensure that the mask plate is in close contact with the heating sheet and is evenly heated, thereby improving the heat conduction efficiency;

[0051] Step 3: As Figure 5As shown in (b), first, a ceramic substrate with a Cu pad on its surface, an intermediate pure Sn solder, and a chip with a Cu pad on its surface are successively placed into the customized through-holes of a mask plate, forming a combined structure with the ceramic substrate / Cu pad / pure Sn solder / Cu pad / power chip from bottom to top. Among them, the pure Sn solder intermediate layer adopts an electroplating process and is respectively prepared on the Cu pad surfaces of the chip and the ceramic substrate; eight long strips obtained when processing the through-holes of the mask plate are used as pressing blocks to ensure a good fit between the through-holes of the mask plate and the pressing blocks; all the pressing blocks are placed and closely attached to the upper surface of the chip. Then, the horizontal slide under the mounting plate is adjusted to align the groove of the mounting plate with the pressing plate of the lifting mechanism in the vertical direction. The motor is controlled to slowly lower the pressing plate until the pressing plate enters the groove of the mounting plate and is in close contact with the pressing blocks. The pressing plate conducts the pressure to the upper surface of the chip through the pressing blocks, thereby realizing the pressurization process of the combined structure; conversely, controlling the motor to slowly raise the pressing plate can reduce the pressure. Among them, it is required that the pressing plate be processed to have the same length and width as the groove of the mounting plate and the mask plate.

[0052] Step Four: After the pressing plate is in close contact with the pressing blocks, an accurate pressure value is read with the help of a pressure sensor, and the pressure value can be adjusted according to requirements. Then, the heating temperature is set to 240 °C on a high-precision temperature controller. The heating sheet is in close contact with the substrate through thermal conductive silicone grease, realizing high-efficiency heat transfer and ensuring uniform heating of the entire combined structure of the ceramic substrate / Cu pad / pure Sn solder / Cu pad / power chip. When the heating sheet reaches 240 °C, welding starts and it is kept at 240 °C for 3 hours to enable sufficient atomic diffusion between the molten intermediate pure Sn solder and the Cu pads, generating Cu-Sn intermetallic compounds.

[0053] Step Five: As Figure 5 As shown in (c), after keeping it at 240 °C for 3 hours, heating is stopped and welding stops. The motor is controlled to slowly raise the pressing plate, and the magnet above the pressing plate simultaneously adsorbs the pressing plate and the pressing blocks, taking away the eight pressing blocks at the same time; at this time, after sufficient atomic diffusion, a structure of ceramic substrate / Cu pad / Cu-Sn intermetallic compound / Cu pad / power chip is formed. Finally, the above eight structures with all Cu-Sn intermetallic compound solder joints are taken out to complete the TLP welding process. The taking-out process is as Figure 5 shown in (d);

[0054] The above embodiments are further detailed descriptions of the present invention and are not used to limit the present invention. The materials and process conditions used are limited to the above embodiments. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention are included within the protection scope of the present invention.

Claims

1. A welding device with controllable parameters and capable of batch-producing TLP welding layers, characterized in that: It comprises a support stand with adjustable height (1), a horizontal carrier plate (2), a combination structure of a horizontal slide and a mounting plate (3), a pressure plate (4); a magnet (5), a connecting rod (6), a pressure sensor (7), a lifting mechanism adapter plate (8), a lifting mechanism conveyor belt structure (9), a motor (10), a lifting mechanism transmission shaft (11), and a lifting mechanism support frame (12); Assuming that the direction of the plane where the horizontal carrier (2) is located is the horizontal direction, and the vertical direction of the horizontal carrier is the vertical direction. In the device, four support legs (1) are installed at the bottom of the horizontal carrier (2) for bearing weight, and the support legs (1) can be adjusted in the vertical direction by adjusting nuts and bolts to meet different needs; the horizontal carrier (2) is respectively installed with a lifting mechanism, a combination structure of a horizontal slide and a mounting plate (3). In the lifting mechanism, a steel structure support frame (12) as the main load-bearing part provides a stable support for the lifting structure. A motor (10) and a vertical transmission shaft (11) are installed on the support frame (12). The motor (10) and the vertical transmission shaft (11) are connected through a conveyor belt structure (9); one end of an adapter plate (8) with a horizontal structure is installed on the transmission shaft (11), and the two are connected and transmitted through internal and external threads. The transmission shaft (11) has an external thread, and the adapter plate (8) has an internal thread through hole; when the conveyor belt (9) rotates forward or reversely, it drives the transmission shaft (11) to rotate clockwise or counterclockwise, and transmits through the threaded structure. The adapter plate (8) is moved vertically upward or downward; while the adapter plate (8) is connected to the transmission shaft (11), the support frame (12) is also provided with a vertical slide rail to limit the adapter plate (8), so that the adapter plate (8) can only move in the vertical direction, and it is ensured that the adapter plate will not rotate in the horizontal direction due to the transmission of the threaded structure; the pressure sensor (7), the connecting rod (6), the magnet (5) and the pressure plate (4) are installed in sequence from top to bottom along the vertical direction below the other end of the adapter plate (8), wherein the magnet (5) is connected to the pressure plate (4) by magnetic attraction; the adapter plate (8) limits the pressure plate (4) to move only in the vertical direction, ensuring that pressure is evenly applied to the upper surface of the chip. The combined structure (3) of the horizontal slide and the mounting plate comprises, from top to bottom, a mounting plate (13) and a horizontal slide, which are connected by screws (27); a groove having the same length and width as the mask plate (14) is formed above the mounting plate (13); the mask plate (14) is formed with a plurality of through-slot arrays, each through-slot corresponds to a chip and substrate to be welded, and each through-slot is formed according to the length and width of the chip and substrate to be welded; a pressing block (15) is provided above the mask plate (14) to press The lower surface of the block (15) has a protrusion, and the protrusion matches the through groove of the mask plate (14) one by one. A slot is provided on one side of the mounting plate (13) for inserting the heating plate (26) from the slot to the bottom of the groove of the mounting plate (13). The heating plate fixing plate (17) is used to limit the horizontal displacement of the heating plate (26). When in use, the heating plate fixing plate (17) is inserted into the side slot (13) of the mounting plate on both sides of the heating plate (26), and then fixed from the top of the slot using screws (16); The horizontal slide table can enable the mounting plate (13) to achieve high-precision displacement in the horizontal direction; In addition, the motor (10) of the lifting mechanism is equipped with a special numerical control system, which uses an external device to synchronously read the value of the pressure sensor (7), and controls the lifting of the motor through the numerical control system, thereby achieving precise control of the pressure.

2. A welding device according to claim 1, wherein the parameters of the welding device can be controlled and the TLP welding layer can be prepared in batches, characterized in that: The horizontal slide can achieve high-precision displacement of the mounting plate (13) in the horizontal direction, and a commercial structure that can accurately control the horizontal displacement to the left and right can be used. For example, the horizontal slide includes an upper Y-axis slide (18) and a lower X-axis slide (19). The Y-axis slide (18) and the X-axis slide (19) are fixed by screws (23) and screws (20) respectively. The Y-axis slide (18) is equipped with a first screw rod (25), and the X-axis slide (19) is equipped with a second screw rod (21). The displacement of the horizontal slide in the X-axis and Y-axis directions can be adjusted by adjusting the first screw rod (25) and the second screw rod (21). The two slides are connected by a slide connecting plate (22), and the horizontal slide as a whole is connected to the upper mounting plate (13) by a threaded connecting plate (24).

3. A method for batch welding using the device according to claim 1 or 2, characterized in that: The following steps are involved: Step 1: providing a chip and a substrate, which are respectively located on the upper and lower sides of the middle layer solder, preparing a first metal pad on the surface of the chip, and preparing a second metal pad on the surface of the substrate; in addition, as needed, a first metal coating and a second metal coating can be selectively prepared on the surface of the first metal pad and the surface of the second metal pad, respectively; Step 2: Provide a mounting plate (13), a heating plate (26) and a mask plate (14), first connect the mounting plate (13) to the high-precision horizontal slide below, then insert the heating plate (26) from the slot on the side of the mounting plate (13), then insert the heating plate fixing plate (17) into the left and right sides of the mounting plate slot, and reserve a certain space in the middle of the slot for the wire of the heating plate. The screw (16) limits the displacement of the heating plate fixing plate (17) from above, thereby fixing the heating plate (26). (26) is connected to an external high-precision temperature controller to monitor the average temperature of the heating plate in real time. Finally, the mask plate (14) is placed vertically into the groove above the mounting plate (13) to fit tightly with the heating plate (26). Before placing the mask plate (14), a thin layer of thermal conductive silicone grease is applied to the surface of the heating plate (26) to ensure that the mask plate is in close contact with the heating plate and is evenly heated, thereby improving the thermal conductivity. In addition, the through grooves of corresponding sizes in the mask plate can be customized according to the sizes of the chip and the substrate; Step 3: first, place the substrate, the middle layer solder and the chip into the through groove of the mask plate in sequence to form a combined structure of substrate / first metal pad / middle layer solder / second metal pad / chip from bottom to top, place the pressing block (15) and make it fit tightly against the upper surface of the chip, then adjust the horizontal slide below the mounting plate (13) so that the groove of the mounting plate (13) is aligned with the pressing plate (4) of the lifting mechanism in the vertical direction, control the motor (10) to slowly lower the pressing plate until the pressing plate (4) enters the groove of the mounting plate (13) and is in close contact with the pressing block (15), and the pressing plate (4) transmits the pressure to the upper surface of the chip through the pressing block (15), thereby realizing the pressurization process of the above-mentioned combined structure, and conversely, control the motor to slowly raise the pressing plate to reduce the pressure; Step 4: When the pressing plate (4) and the pressing block (15) are in close contact, the pressure sensor (7) is used to read the accurate pressure value, and the pressure value can be adjusted according to the demand. Then, the heating temperature is set on the external temperature controller. The heating plate is in close contact with the substrate through the thermal grease, so that high-efficiency heat transfer is achieved, ensuring that the entire structure is heated evenly during the welding process. When the heating plate reaches the required temperature, welding is started, and the temperature is kept at the set temperature for a period of time to allow sufficient atomic diffusion to occur between the molten intermediate layer solder and the first metal pad and the second metal pad. Step 5: After keeping warm for the required time, stop heating and stop welding, control the motor to slowly raise the pressing plate, and the magnet above the pressing plate will simultaneously adsorb the pressing plate and the pressing blocks, and all the pressing blocks will be taken away at the same time. At this time, sufficient atomic diffusion has been performed to form a structure of substrate / first metal pad / intermetallic compound / second metal pad / chip, and finally the above structure with all intermetallic compound solder joints can be taken out.

4. The method according to claim 3, characterized in that In step 1, the substrate is a PCB substrate or a ceramic substrate; The first metal pad and the second metal pad have the same material, which is Cu; The first metal coating and the second metal coating have the same material, such as one of Ni, Ni-P, Ni-WP, Co, Co-P, Co-W, Co-WP, Fe, and Ni-Fe-P; The first metal plating layer and the second metal plating layer play a role in improving the wettability of the pad surface and diffusion barrier.

5. The method according to claim 3, characterized in that In step 2, the side of the mounting plate has a slot with the same length and height as the heating plate; the top of the mounting plate has a groove with the same length and width as the mask; the length and width of the heating plate are the same as the mask; the material of the heating plate is silicone glass fiber or ceramic or aluminum alloy; the mask has a through groove with the same length and width as the chip and substrate.

6. The method according to claim 3, characterized in that In step three, the intermediate layer solder is one of pure Sn, Sn-Cu, Sn-Ag, Sn-Ag-Cu, Sn-Bi, Sn-Pb, Sn-Zn, Sn-In, Sn-Sb, and Sn-Au; the intermediate layer solder can be prepared on the surface of the first metal pad and the second metal pad by a deposition process, or inserted between the first metal pad and the second metal pad in the form of a solder sheet; the pressing plate has the same length and width as the mounting plate groove and the mask plate.

7. The method according to claim 3, characterized in that In step 4, the heating temperature is the temperature of the entire heating plate; the heating temperature range is 200°C to 380°C; the combined structure is substrate / first metal pad / middle layer solder / second metal pad / chip.

8. The method according to claim 3, characterized in that In step five, the intermetallic compound is one of Cu-Sn, Ni-Sn, Co-Sn, and Fe-Sn intermetallic compounds.

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