Power device connection device and method

Abstract

The present invention relates to the field of semiconductor packaging, and discloses a power device connection device and method, wherein the device heats and pressurizes multiple power devices through a heating and sintering platform; a bottom electric cylinder assembly is arranged under the heating and sintering platform; a multi-modal press head assembly is arranged above the heating and sintering platform; when the heating and sintering platform and the multi-modal press head assembly reach a preset mold closing condition, the heating and sintering platform is driven to rise by the bottom electric cylinder assembly, so that the heating and sintering platform and the multi-modal press head assembly are molded to form a heating and pressurizing cabin; when heating and pressurizing sintering is performed, the heating and pressurizing cabin is an oxygen-free environment; the multi-modal press head assembly is provided with at least two hydraulic oil circuits; the hydraulic oil circuits are controlled by independent servo proportional valves and reversing valves. The device provided by the present invention uses a multi-modal press head assembly to sinter power devices, which greatly improves the sintering quality and efficiency of power devices.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor packaging, and in particular to a power device connection device and method. Background Art

[0002] Power devices, especially high-power devices, have high requirements for sintering process. The strength and thermal resistance of the sintered layer have a significant impact on the power density and integration of high-power devices. Summary of the invention

[0003] Based on this, a power device connection device and method are provided to improve the sintering quality of the power device.

[0004] A power device connection device, which heats and pressurizes a plurality of power devices for sintering by heating a sintering platform;

[0005] A bottom electric cylinder assembly is disposed below the heating and sintering platform; a multi-modal pressing head assembly is disposed above the heating and sintering platform;

[0006] When the heating and sintering platform and the multi-modal press head assembly reach a preset mold closing condition, the heating and sintering platform is driven to rise by the bottom electric cylinder assembly, so that the heating and sintering platform and the multi-modal press head assembly are molded to form a heating and pressurizing chamber; when the heating and pressurizing sintering is performed, the heating and pressurizing chamber is an oxygen-free environment;

[0007] The multi-modal pressure head assembly is provided with at least two hydraulic oil circuits; the hydraulic oil circuits are controlled by independent servo proportional valves and reversing valves; the hydraulic oil circuits are provided with a hydraulic plate, and a plurality of hydraulic cylinders are installed on the hydraulic plate; each of the hydraulic cylinders corresponds to a pressure rod, which is used to apply a target pressure to the power device alone;

[0008] A cooling plate, a heat insulating plate and a heating plate are sequentially arranged on the side of the hydraulic plate close to the power device; the cooling plate is used to prevent the hydraulic plate from overheating; the heat insulating plate is used to reduce the heat generated by the heating plate from being transferred to the hydraulic plate; the heating plate is used to heat the power device to the target sintering temperature.

[0009] Optionally, the hydraulic cylinder and the pressure rod are connected via a transfer rod.

[0010] Optionally, the preheating station is provided with a first preheating chamber; the first preheating chamber is provided with a first air extraction port and a first inert gas interface;

[0011] The first air extraction port is used to reduce the air pressure of the first preheating chamber to a first vacuum degree after the power device is transferred to the preheating station;

[0012] The first inert gas interface is used to introduce inert gas into the first preheating chamber after the air pressure in the first preheating chamber is reduced to a first vacuum degree, so that the air pressure in the first preheating chamber reaches a first preset air pressure.

[0013] Optionally, when the air pressure in the first preheating chamber is reduced to the first vacuum degree and maintained for a first specified time, the first air extraction port is closed;

[0014] After closing the first gas extraction port, or at a second specified time before closing the first gas extraction port, the first inert gas interface is opened; the inert gas includes nitrogen.

[0015] Optionally, the preheating station is provided with a second preheating chamber; the second preheating chamber is provided with a second air extraction port and a gasifiable reduction material interface;

[0016] The second air extraction port is used to reduce the air pressure of the second preheating chamber to a second vacuum degree after the power device is moved into the second preheating chamber or the first preheating chamber is switched to the second preheating chamber;

[0017] The gasifiable reducing material interface is used to add the gasifiable reducing material into the second preheating chamber after the air pressure in the second preheating chamber is reduced to the first vacuum degree, so that the air pressure in the second preheating chamber reaches the second preset air pressure.

[0018] Optionally, when the air pressure in the second preheating chamber is reduced to the second vacuum degree and maintained for a third specified time, the second air extraction port is closed;

[0019] After closing the second gas suction port, or at a fourth designated time before closing the second gas suction port, the gasifiable reducing material interface is opened; the gasifiable reducing material includes formic acid.

[0020] Optionally, the power device connection device is provided with a film winding mechanism;

[0021] The film winding mechanism is used to cover the power device with a protective film after the power device is transferred to the heating and sintering platform.

[0022] Optionally, the power device connection device is provided with a back force mechanism;

[0023] After the heating and sintering platform and the multi-modal pressure head assembly are molded together, the back force mechanism enters a working state to support the pressure borne by the heating and sintering platform;

[0024] After the back force mechanism enters the working state, the bottom electric cylinder assembly unloads the thrust on the heating and sintering platform.

[0025] Optionally, the heating and pressurizing cabin is provided with a third air extraction port and a second inert gas interface;

[0026] The third air extraction port is used to reduce the air pressure of the heating and pressurizing cabin to a third vacuum degree;

[0027] The second inert gas interface is used to introduce inert gas into the heating and pressurizing cabin after the air pressure in the heating and pressurizing cabin drops to a third vacuum degree, so that the air pressure in the heating and pressurizing cabin reaches a third preset air pressure.

[0028] Optionally, the cooling station is provided with a third inert gas interface and a coolant interface;

[0029] The third inert gas interface is used to deliver inert gas to the cooling station;

[0030] The coolant interface is used to provide coolant to the cooling station to cool the power device to the preset target cooling temperature.

[0031] A power device connection method is applied to any of the above-mentioned power device connection devices; the power device connection device is provided with a transfer component, a preheating station, a heating and sintering platform and a cooling station; the method comprises:

[0032] The power device to be processed is transferred to the preheating station by the transfer assembly, and the power device is preheated to a specified preheating temperature;

[0033] The power device preheated to the specified preheating temperature is transferred to the heating and sintering platform by the transfer component, and the power device is heated and pressurized for sintering in an oxygen-free atmosphere;

[0034] The sintered power device is transferred to the cooling station by the transfer assembly, and the power device is cooled to a preset target cooling temperature in an oxygen-free atmosphere.

[0035] The power device connection apparatus and method described above use a multi-modal press head assembly to sinter the power device, which greatly improves the sintering quality and efficiency of the power device. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required for use in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative labor.

[0037] Figure 1 is a three-dimensional diagram of a power device connection device in one embodiment of the present invention;

[0038] Figure 2 is a front view of a power device connection device in one embodiment of the present invention;

[0039] Figure 3 is a cross-sectional view of a multi-modal pressure head assembly in a power device connection device according to an embodiment of the present invention;

[0040] Figure 4 It is a schematic diagram of the structure of a power device in one embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0042] like Figures 1 to 3 As shown, an embodiment of the present invention provides a power device connection device, which heats and pressurizes a plurality of power devices by heating a sintering platform 9;

[0043] A bottom electric cylinder assembly 10 is arranged below the heating and sintering platform 9; a multi-modal pressing head assembly 8 is arranged above the heating and sintering platform 9;

[0044] When the heating and sintering platform 9 and the multi-modal pressing head assembly 8 reach the preset mold closing condition, the heating and sintering platform 9 is driven to rise by the bottom electric cylinder assembly 10, so that the heating and sintering platform 9 and the multi-modal pressing head assembly 8 are molded to form a heating and pressurizing chamber; when the heating and pressurizing sintering is performed, the heating and pressurizing chamber is an oxygen-free environment;

[0045] The multi-modal pressure head assembly 8 is provided with at least two hydraulic oil circuits; the hydraulic oil circuits are controlled by independent servo proportional valves and reversing valves; the hydraulic oil circuits are provided with a hydraulic plate, and a plurality of hydraulic cylinders 013 are installed on the hydraulic plate; each hydraulic cylinder 013 corresponds to a pressure rod, which is used to apply the target pressure to the power device alone;

[0046] A cooling plate 08, a heat insulating plate 09 and a heating plate 010 are sequentially arranged on the side of the hydraulic plate close to the power device; the cooling plate 08 is used to prevent the hydraulic plate from overheating; the heat insulating plate 09 is used to reduce the heat generated by the heating plate 010 from being transferred to the hydraulic plate; the heating plate 010 is used to heat the power device to the target sintering temperature.

[0047] Understandably, in the process of packaging power devices (especially SiC products), some low-temperature sintering materials are needed for sintering connection to obtain a high-temperature resistant and high-thermal conductive connection interface. Here, nanosilver materials can be used as low-temperature sintering materials. Nanosilver materials can be sintered at low temperatures (<300°C) to obtain a sintered silver chip connection interface with high temperature resistance (>700°C) and high thermal conductivity (~240 W / m·K). Figure 4 As shown, Figure 4 The figure is a schematic diagram of the structure of the power device to be sintered. The power device includes a heat sink, a DBC substrate ceramic layer, a SiC-metal oxide semiconductor field effect transistor, a welding terminal, a gate aluminum wire, a top plate, a source copper wire and a sintering layer (i.e., sintered silver). There are three sintering layers, the first sintering layer is between the heat sink and the DBC substrate ceramic layer, the second sintering layer is between the DBC substrate ceramic layer and the SiC-metal oxide semiconductor field effect transistor, and the third sintering layer is between the SiC-metal oxide semiconductor field effect transistor and the top plate.

[0048] The nanosilver particles are heated to above their melting point to melt the surface of the nanosilver particles, and a solidification process occurs at the same time, so that the vertices are interconnected and merged. This can effectively eliminate the gaps between the nanoparticles and obtain a more dense and uniform silver film. By utilizing the differences in sintering processes, different forms of nanosilver can also be obtained, such as spherical, flat, chain-shaped, etc., to meet the packaging requirements of different power devices. The sintered nanosilver material has a series of excellent properties such as high density, strong conductivity, good thermal stability, high mechanical strength, and good oxidation resistance.

[0049] like Figure 2 As shown, the heating and sintering platform 9 is arranged on the mold frame 7. The mold frame 7 includes an upper mold frame and a lower mold frame. The heating and sintering platform 9 is installed on the lower mold frame, and the lower mold frame is also provided with a bottom electric cylinder assembly 10 and a back force mechanism 11. The upper mold frame is installed with a multimodal press head assembly 8. After the incoming material tray 3 is transferred to the heating and sintering platform 9, the bottom electric cylinder assembly 10 pushes the heating and sintering platform 9 to rise and close the mold with the multimodal press head assembly 8. After the heating and sintering platform 9 rises to its position, the back force mechanism 11 extends out to realize the back force function, with a maximum pressure resistance of 30t. At this time, the bottom electric cylinder assembly 10 can release the force. After closing the mold, the heating and sintering platform 9 and the multimodal press head assembly 8 form a closed cabin, which is evacuated and filled with nitrogen. At the same time, pressure is applied through the multimodal press head assembly 8, and then heated and sintered. The sintering temperature can be set according to actual needs, such as 260°C.

[0050] The preset mold closing conditions can be determined according to the actual process conditions, such as the heating and sintering platform 9 and the multi-modal press head assembly 8 both reach the corresponding working temperature. In one example, the working temperature can be 260°C. After the heating and sintering platform 9 rises to its position, the back force mechanism 11 extends to bear the force, the bottom electric cylinder assembly 10 releases the force, and at the same time, each press head in the multi-modal press head assembly 8 outputs pressure independently to achieve pressurized sintering of each power device.

[0051] During the sintering process of power devices, the applied pressure needs to be precisely controlled to ensure that a high-quality sintered body can be obtained without causing abnormalities in the power device due to excessive pressure. In this embodiment, the multi-modal pressure head assembly is provided with at least two hydraulic oil circuits, such as a first hydraulic oil circuit and a second hydraulic oil circuit. In one example, Figure 3 As shown, the first hydraulic oil circuit includes a first oil inlet 01 and a first hydraulic plate 06, and the second hydraulic oil circuit includes a second oil inlet 02 and a second hydraulic plate 07, wherein a mounting plate 05 is provided above the first hydraulic plate 06. Each hydraulic oil circuit is controlled by an independent servo proportional valve and a reversing valve, and each hydraulic oil circuit can output a specific pressure. Therefore, the multi-modal ram assembly 8 can output two or more pressures, and power devices with different pressure requirements can be sintered in one sintering process, greatly improving equipment utilization and sintering efficiency.

[0052] The hydraulic oil circuit is provided with a hydraulic plate, on which a number of hydraulic cylinders 013 are installed; each hydraulic cylinder 013 corresponds to a pressure rod, which is used to apply a target pressure to the power device individually, and can accurately control the pressure of each power device to ensure the quality of each power device. Here, the hydraulic cylinder 013 is a micro ultra-high pressure hydraulic cylinder with a piston area of ​​0.5cm².

[0053] On the side of the hydraulic plate close to the power device, a cooling plate 08, a heat insulation plate 09 and a heating plate 010 are arranged in sequence. Among them, the cooling plate 08 dissipates heat through the cooling water flowing in the cooling water channel to prevent the hydraulic plate from overheating. In one example, the cooling water channel takes in water through the water inlet 03 and discharges water through the water outlet 04. The heat insulation plate 09 is made of a heat-insulating material and is used to reduce the heat generated by the heating plate 010 from being transferred to the hydraulic plate, causing the hydraulic cylinder 013 on the hydraulic plate to overheat. The heating plate 010 is used to heat the power device to the target sintering temperature. In one example, a bottom guard plate 011 is provided on the outer side of the heating plate, which can serve as a supporting structure of the heating plate to help fix the position of the heating plate. A temperature sensor 014 is provided on the heating plate 010. The temperature sensor 014 can be a PT100 (platinum resistance thermometer) to monitor the temperature of the heating plate.

[0054] Through the three structures of cooling plate 08, heat insulation plate 09 and heating plate 010, on the one hand, it can ensure that the power device rises to the target sintering temperature, and on the other hand, it can prevent the hydraulic cylinder from overheating and ensure that the pressure applied to the power device is stable.

[0055] This embodiment uses a multi-modal press head assembly to sinter the power device, which greatly improves the sintering quality and efficiency of the power device.

[0056] Optionally, the hydraulic cylinder 013 and the pressure rod are connected via a transfer rod.

[0057] Understandably, the hydraulic cylinder 013 and the pressure rod can be connected by a transfer rod. The use of the transfer rod increases the distance between the pressure head 012 of the pressure rod and the hydraulic cylinder 013, reduces the impact of the high temperature at the pressure head 012 on the hydraulic cylinder 013; increases the flexibility of the system, simplifies the design of the system, avoids complex hydraulic cylinder installation and layout, and reduces manufacturing costs; can be used to compensate for the distance between the installation position of the hydraulic cylinder 013 and the pressure rod, ensuring that the thrust of the hydraulic cylinder 013 can be effectively transmitted to the pressure rod.

[0058] Optionally, the power device connection device is further provided with a transfer assembly, a preheating station 5 and a cooling station 14;

[0059] The transfer assembly is used to transfer the power device to be processed to the preheating station 5;

[0060] A preheating station 5, used for preheating the power device to a specified preheating temperature;

[0061] The transfer assembly is also used to transfer the power device to the heating and sintering platform 9;

[0062] The transfer assembly is also used to transfer the sintered power device to the cooling station 14;

[0063] The cooling station 14 is used to cool the power device to a preset target cooling temperature in an oxygen-free atmosphere.

[0064] The power device connection device provided in this embodiment is used to sinter the power device printed with the low-temperature sintering material. The power device connection device is provided with a transfer assembly, a preheating station 5, a heating sintering platform 9 and a cooling station 14. The transfer assembly includes a loading and transferring mechanism 1, a loading tray grabbing mechanism 2, and a unloading and transferring mechanism 12. The power device to be processed can be placed on the incoming material tray 3. The incoming material tray 3 can be customized according to the actual size of the power device. In one example, the incoming material tray 3 can hold 6 power devices. The incoming material tray 3 is conveyed by the loading conveyor line 4. The loading conveyor line 4 is provided with an incoming material sensor and an industrial camera, and the incoming material sensor is used to determine whether there is an incoming material tray 3 at the entrance of the power device connection device. If there is an incoming material tray 3, the industrial camera is enabled, and the industrial camera is used to determine whether the power device loaded in the incoming material tray 3 is placed correctly. If the power device is placed correctly, the incoming material tray 3 is transferred to the preheating station 5. The preheating station 5 is provided with an in-place sensor to determine whether the parking position of the incoming material tray 3 is accurate. If the power device is placed incorrectly, a warning light will be used to give a warning.

[0065] The power device arrives at the preheating station 5 along with the incoming material tray 3 and is preheated at the preheating station 5. The preheating temperature and time can be set according to actual needs. In some examples, the specified preheating temperature can be 120°C~150°C. During the preheating process, an oxygen-free atmosphere, such as a nitrogen environment or a vacuum environment, can be provided.

[0066] After preheating is completed, the incoming material tray 3 can be grabbed by the loading tray grabbing mechanism 2, and the incoming material tray 3 can be transferred to the heating and sintering platform 9 by the loading and transferring mechanism 1. Among them, the loading tray grabbing mechanism 2 is composed of a mounting bracket, a grabbing cylinder mechanism, a nitrogen nozzle circuit, a guide positioning, etc. The mounting bracket is responsible for carrying and fixing the grabbing cylinder mechanism, the nitrogen nozzle circuit and the guide positioning. The grabbing cylinder mechanism is used to provide power to achieve the grabbing action. Through the telescopic movement of the cylinder, the clamping and release of the incoming material tray 3 can be achieved. The nitrogen nozzle circuit can spray nitrogen to the incoming material tray 3 to provide a nitrogen atmosphere for the power device. The guide positioning ensures that the incoming material tray 3 is accurately transferred to the heating and sintering platform 9. The loading and transferring mechanism 1 realizes the Z-axis movement of the mechanism by the Z-axis servo screw mechanism in conjunction with the guide rail slider mechanism, and realizes the Y-axis movement by the servo reducer in conjunction with the gear rack and the guide rail slider. The loading and transferring mechanism 1 realizes the X-axis movement on the servo transfer mechanism. The loading and transferring mechanism 1 can accurately move and position materials or pallets in three-dimensional space.

[0067] The heating sintering platform 9 is used to sinter the power device. After sintering, the material tray 3 can be transferred to the cooling station 14 through the material transfer mechanism 12. The material transfer mechanism realizes the Z-axis movement of the mechanism by the Z-axis servo screw mechanism in conjunction with the guide rail slider mechanism, and realizes the Y-axis movement by the servo reducer in conjunction with the gear rack and the guide rail slider. The material transfer mechanism 12 realizes the X-axis movement on the servo transfer mechanism. The structure of the material transfer mechanism 12 is similar to that of the material transfer mechanism 1, but the function is opposite.

[0068] The cooling station 14 can provide cooling in an oxygen-free atmosphere. In one example, nitrogen and cooling water can be passed for cooling. When the power device is cooled to the preset target cooling temperature, it indicates that the cooling is completed. The unloading and transferring mechanism 12 can put the cooled incoming material tray 3 (here referred to as the unloading tray 13) into the unloading conveyor line 15. The unloading conveyor line 15 transports the unloading tray 13 to the unloading port for manual unloading.

[0069] The power device connection device provided in this embodiment is provided with a transfer assembly, a preheating station 5, a heating sintering platform 9 and a cooling station 14, which can provide inert gas protection throughout the sintering process of the power device, as well as sintering under precise pressure, greatly improving the sintering quality of the power device.

[0070] Optionally, the preheating station 5 is provided with a first preheating chamber; the first preheating chamber is provided with a first air extraction port and a first inert gas interface;

[0071] The first air extraction port is used to reduce the air pressure of the first preheating chamber to a first vacuum degree after the power device is transferred to the preheating station 5;

[0072] The first inert gas interface is used to introduce inert gas into the first preheating chamber after the air pressure in the first preheating chamber is reduced to a first vacuum degree, so that the air pressure in the first preheating chamber reaches a first preset air pressure.

[0073] Understandably, the preheating station 5 is provided with a first preheating chamber. The first preheating chamber is provided with a first air extraction port and a first inert gas interface. The first air extraction port is connected to the vacuum system 17. After the power device enters the first preheating chamber, the air pressure of the first preheating chamber is first reduced to a first vacuum degree, such as below 1 mBar, by the vacuum system 17, and then an inert gas is introduced to make the air pressure of the first preheating chamber reach a first preset air pressure, such as nitrogen, and the first preset air pressure can be 1000 mbar. Then the temperature is increased and heated, and after reaching the preset temperature, it can enter the second preheating chamber.

[0074] Optionally, when the air pressure in the first preheating chamber is reduced to the first vacuum degree and maintained for a first specified time, the first air extraction port is closed;

[0075] After closing the first gas extraction port, or at a second specified time before closing the first gas extraction port, the first inert gas interface is opened; the inert gas includes nitrogen.

[0076] Understandably, the air pressure in the first preheating chamber is reduced to the first vacuum degree, maintained for the first specified time, and the first gas outlet is closed. The first specified time can be set according to actual needs, such as 0~1min. After closing the first gas outlet, the inert gas is introduced to save the amount of inert gas. At the second specified time before closing the first gas outlet, the first inert gas interface is opened and the inert gas is introduced, which can further reduce the oxygen content in the preheating chamber and improve the sintering quality. According to actual process requirements, it can be selected to close the first gas outlet and then introduce the inert gas, or to open the first inert gas interface at the second specified time before closing the first gas outlet. The second specified time can be set according to actual needs, such as 10s~120s.

[0077] Optionally, the preheating station 5 is provided with a second preheating chamber; the second preheating chamber is provided with a second air extraction port and a gasifiable reduction material interface;

[0078] The second air extraction port is used to reduce the air pressure of the second preheating chamber to a second vacuum degree after the power device is moved into the second preheating chamber or the first preheating chamber is switched to the second preheating chamber;

[0079] The gasifiable reducing material interface is used to add the gasifiable reducing material into the second preheating chamber after the air pressure in the second preheating chamber is reduced to a second vacuum degree, so that the air pressure in the second preheating chamber reaches a second preset air pressure.

[0080] Understandably, the second preheating chamber can be a preheating chamber that is different in space or time (process conditions). The second preheating chamber is provided with a second air extraction port and a gasifiable reducing material interface. The second air extraction port is connected to the vacuum system 17. After the power device enters the second preheating chamber, the air pressure of the second preheating chamber is first reduced to a second vacuum degree, such as below 1 mBar, by the vacuum system 17, and then the gasifiable reducing material is added so that the air pressure of the gasifiable reducing material in the second preheating chamber reaches the second preset air pressure, such as the gasifiable reducing material can be formic acid, the formic acid flow rate can be 30 L / min, and the second preset air pressure can be 950 mbar. Then the temperature is raised to 200°C, maintained for 30 seconds, and then vacuumed to 1 mbar.

[0081] Optionally, when the air pressure in the second preheating chamber is reduced to the second vacuum degree and maintained for a third specified time, the second air extraction port is closed;

[0082] After closing the second gas suction port, or at a fourth designated time before closing the second gas suction port, the gasifiable reducing material interface is opened; the gasifiable reducing material includes formic acid.

[0083] Understandably, the air pressure in the second preheating chamber is reduced to the second vacuum degree, maintained for the third specified time, and the second air exhaust port is closed. The third specified time can be set according to actual needs, such as 0~1min. After closing the second air exhaust port, the gasifiable reducing material interface is opened again to save the amount of gasifiable reducing material. At the fourth specified time before closing the second air exhaust port, the gasifiable reducing material interface is opened and the gasifiable reducing material is added, which can further reduce the oxygen content in the preheating chamber and improve the sintering quality. According to actual process requirements, it can be selected to add the gasifiable reducing material after closing the second air exhaust port, or to open the gasifiable reducing material interface at the fourth specified time before closing the second air exhaust port. The fourth specified time can be set according to actual needs, such as 10s~2min.

[0084] Optionally, the power device connection device is provided with a film winding mechanism 6;

[0085] The film winding mechanism 6 is used to cover the power device with a protective film after the power device is transferred to the heating and sintering platform 9 .

[0086] It can be understood that the film winding mechanism 6 includes a feeding mechanism and a receiving mechanism. Before sintering the power device, a protective film needs to be covered on the power device to isolate and protect it from being crushed. Here, the protective film can be a Teflon film with a thickness of 0.1 mm. After sintering a plate of products, the winding mechanism automatically feeds a section.

[0087] Optionally, the multi-modal press head assembly 8 includes a plurality of press heads;

[0088] The multi-modal pressure head assembly 8 is connected to a servo oil pump system; the servo oil pump system is used to provide pressure output for each pressure head; wherein the servo oil pump system outputs multiple oil pressures simultaneously.

[0089] Understandably, the multi-modal pressure head assembly 8 is connected to the full servo oil pump system 16. In one example, the maximum pressure of the full servo oil pump system 16 can reach 25MPa, and it can stably output 4 oil pressures of different pressures at the same time. Each oil pressure is controlled by a special high-pressure servo proportional valve, pressure sensor, and reversing valve, which can output high-precision oil pressure, and the oil pressure accuracy can reach ±0.5% of the full range. In actual production, through the special structure in the multi-modal pressure head assembly, the pressure on the chip is twice the system pressure, that is, the maximum pressure on the chip is 50MPA.

[0090] Optionally, the power device connection device is provided with a back force mechanism 11;

[0091] After the heating and sintering platform 9 and the multi-modal pressing head assembly 8 are molded together, the back force mechanism 11 enters a working state to support the pressure on the heating and sintering platform 9;

[0092] After the back force mechanism 11 enters the working state, the bottom electric cylinder assembly 10 unloads the thrust on the heating and sintering platform 9 .

[0093] It is understandable that after the heating and sintering platform 9 and the multimodal pressure head assembly 8 are molded together, the back force mechanism 11 extends and enters the working state to realize the back force function, which is used to support the pressure on the heating and sintering platform 9. In one example, the maximum pressure resistance of the back force mechanism 11 can reach 30t, which can support 8 groups of power devices to sinter and maintain pressure at the same time. After the back force mechanism 11 enters the working state, the bottom electric cylinder assembly 10 unloads the thrust on the heating and sintering platform 9. After the bottom electric cylinder assembly 10 unloads the force, it can be free from the pressure applied by the multimodal pressure head assembly 8, extending the service life.

[0094] Optionally, the heating and pressurizing cabin is provided with a third air extraction port and a second inert gas interface;

[0095] The third air extraction port is used to reduce the air pressure of the heating and pressurizing cabin to a third vacuum degree;

[0096] The second inert gas interface is used to introduce inert gas into the heating and pressurizing cabin after the air pressure in the heating and pressurizing cabin drops to a third vacuum degree, so that the air pressure in the heating and pressurizing cabin reaches a third preset air pressure.

[0097] Understandably, the heating and sintering platform 9 is molded with the multimodal press head assembly 8 to form a heating and pressurizing cabin. The heating and pressurizing cabin is provided with a third air extraction port and a second inert gas interface. The third air extraction port can be provided on the multimodal press head assembly 8 or on the heating and sintering platform 9. The second inert gas interface can be provided on the multimodal press head assembly 8 or on the heating and sintering platform 9. The third air extraction port is connected to the vacuum system 17.

[0098] In one example, after the power device enters the heated and pressurized chamber, the air pressure of the heated and pressurized chamber is first reduced to a third vacuum degree, such as below 1 mBar, through the vacuum system 17, and then the temperature is raised to the target welding temperature, such as 260°C. After reaching the target welding temperature, it is maintained for 30 seconds, and then evacuated to 1 mbar. After reaching 1 mbar, it is maintained for 60 seconds, and nitrogen is filled to 1000 mbar to reach normal pressure. Among them, the nitrogen flow rate can be 20L / min. The heated and pressurized chamber can adopt PID temperature control, and the temperature control range includes 25°C~320°C±1°C.

[0099] In some examples, the vacuum system 17 can use a bipolar vacuum pump in conjunction with vacuum valves, vacuum filters and other components to achieve the vacuuming function of the heated and compressed cabin, providing an oxygen-free environment for the heated and compressed cabin. The vacuuming rate can be 40L / min. Instruments such as a negative pressure gauge, an oxygen analyzer, and a vacuum gauge can be provided for the heated and compressed cabin to detect whether the oxygen-free environment meets the standard.

[0100] Optionally, the cooling station is provided with a third inert gas interface and a coolant interface;

[0101] The third inert gas interface is used to deliver inert gas to the cooling station;

[0102] The coolant interface is used to provide coolant to the cooling station to cool the power device to the preset target cooling temperature.

[0103] Understandably, the cooling station is provided with a third inert gas interface and a coolant interface. Among them, the third inert gas interface is used to deliver an inert gas, such as nitrogen, to the cooling station. The coolant interface is used to provide coolant to the cooling station to cool the power device to a preset target cooling temperature. In some examples, the coolant can be water, such as cooling water with a temperature of 10°C to 25°C, and the preset target cooling temperature can be set according to actual needs, such as 35°C to 45°C.

[0104] In one example, if Figure 2 As shown, the power device connection device can be supported by a welded frame 18. The power device connection device can also be provided with a human-machine interaction device (HMI) and a frame housing. The human-machine interaction device can be a cantilever HMI, which is convenient for personnel to operate. The frame housing can be composed of painted sheet metal and acrylic board, which is beautiful and generous.

[0105] In one embodiment, a power device connection method is provided, which is applied to any of the above-mentioned power device connection devices; the power device connection device is provided with a transfer component, a preheating station, a heating and sintering platform and a cooling station; the method comprises:

[0106] The power device to be processed is transferred to the preheating station by the transfer assembly, and the power device is preheated to a specified preheating temperature;

[0107] The power device preheated to the specified preheating temperature is transferred to the heating and sintering platform by the transfer component, and the power device is heated and pressurized for sintering in an oxygen-free atmosphere;

[0108] The sintered power device is transferred to the cooling station by the transfer assembly, and the power device is cooled to a preset target cooling temperature in an oxygen-free atmosphere.

[0109] It should be understood that the order of execution of the steps in the above embodiment does not necessarily mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present invention.

[0110] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A power device connection device, characterized in that: The power device connection device heats and pressurizes the multiple power devices for sintering by heating the sintering platform; A bottom electric cylinder assembly is disposed below the heating and sintering platform; a multi-modal pressing head assembly is disposed above the heating and sintering platform; When the heating and sintering platform and the multi-modal press head assembly reach a preset mold closing condition, the heating and sintering platform is driven to rise by the bottom electric cylinder assembly, so that the heating and sintering platform and the multi-modal press head assembly are molded to form a heating and pressurizing chamber; when the heating and pressurizing sintering is performed, the heating and pressurizing chamber is an oxygen-free environment; The multi-modal pressure head assembly is provided with at least two hydraulic oil circuits; the hydraulic oil circuits are controlled by independent servo proportional valves and reversing valves; the hydraulic oil circuits are provided with a hydraulic plate, and a plurality of hydraulic cylinders are installed on the hydraulic plate; each of the hydraulic cylinders corresponds to a pressure rod, which is used to apply a target pressure to the power device alone; A cooling plate, a heat insulating plate and a heating plate are sequentially arranged on the side of the hydraulic plate close to the power device; the cooling plate is used to prevent the hydraulic plate from overheating; the heat insulating plate is used to reduce the heat generated by the heating plate from being transferred to the hydraulic plate; the heating plate is used to heat the power device to the target sintering temperature.

2. The power device connection device according to claim 1, characterized in that: The hydraulic cylinder and the pressure rod are connected via a transfer rod.

3. The power device connection device according to claim 1, characterized in that: The power device connection device is also provided with a transfer assembly, a preheating station and a cooling station; The transfer assembly is used to transfer the power device to be processed to the preheating station; The preheating station is used to preheat the power device to a specified preheating temperature; The transfer assembly is also used to transfer the power device to the heating and sintering platform; The transfer assembly is also used to transfer the sintered power device to the cooling station; The cooling station is used to cool the power device to a preset target cooling temperature in an oxygen-free atmosphere.

4. The power device connection device according to claim 3, characterized in that: The preheating station is provided with a first preheating chamber; the first preheating chamber is provided with a first air extraction port and a first inert gas interface; The first air extraction port is used to reduce the air pressure of the first preheating chamber to a first vacuum degree after the power device is transferred to the preheating station; The first inert gas interface is used to introduce inert gas into the first preheating chamber after the air pressure in the first preheating chamber is reduced to a first vacuum degree, so that the air pressure in the first preheating chamber reaches a first preset air pressure.

5. The power device connection device according to claim 4, characterized in that: When the air pressure in the first preheating chamber is reduced to the first vacuum degree and maintained for a first specified time, the first air extraction port is closed; After closing the first gas extraction port, or at a second specified time before closing the first gas extraction port, the first inert gas interface is opened; the inert gas includes nitrogen.

6. The power device connection device according to claim 1, characterized in that: The power device connection device is provided with a film winding mechanism; The film winding mechanism is used to cover the power device with a protective film after the power device is transferred to the heating and sintering platform.

7. The power device connection device according to claim 1, characterized in that: The power device connection device is provided with a back force mechanism; After the heating and sintering platform and the multi-modal pressure head assembly are molded together, the back force mechanism enters a working state to support the pressure borne by the heating and sintering platform; After the back force mechanism enters the working state, the bottom electric cylinder assembly unloads the thrust on the heating and sintering platform.

8. The power device connection device according to claim 1, characterized in that: The heating and pressurizing cabin is provided with a third air extraction port and a second inert gas interface; The third air extraction port is used to reduce the air pressure of the heating and pressurizing cabin to a third vacuum degree; The second inert gas interface is used to introduce inert gas into the heating and pressurizing cabin after the air pressure in the heating and pressurizing cabin drops to a third vacuum degree, so that the air pressure in the heating and pressurizing cabin reaches a third preset air pressure.

9. The power device connection device according to claim 3, characterized in that: The cooling station is provided with a third inert gas interface and a coolant interface; The third inert gas interface is used to deliver inert gas to the cooling station; The coolant interface is used to provide coolant to the cooling station to cool the power device to the preset target cooling temperature.

10. A power device connection method, characterized in that: The method is applied to a power device connection device as claimed in any one of claims 1 to 9; the power device connection device is provided with a transfer component, a preheating station, a heating sintering platform and a cooling station; the method comprises: The power device to be processed is transferred to the preheating station by the transfer assembly, and the power device is preheated to a specified preheating temperature; The power device preheated to the specified preheating temperature is transferred to the heating and sintering platform by the transfer component, and the power device is heated and pressurized for sintering in an oxygen-free atmosphere; The sintered power device is transferred to the cooling station by the transfer assembly, and the power device is cooled to a preset target cooling temperature in an oxygen-free atmosphere.

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