Sealing cavity for semiconductor chip soldering and vacuum eutectic furnace

Abstract

The application relates to the technical field of semiconductor chip welding, in particular to a sealing cavity for semiconductor chip welding and a vacuum eutectic furnace, which comprises an upper cavity, a lower cavity which is arranged opposite to the upper cavity, a sealing cavity formed between the upper cavity and the lower cavity when the upper cavity and the lower cavity are closed, a carrier plate assembly arranged in the sealing cavity and used for placing chips, heating assemblies arranged above and below the carrier plate assembly and used for radiantly heating the carrier plate assembly, and a cooling assembly provided with cooling pipes used for feeding cooling liquid to cool the carrier plate assembly. The application adopts the heating assemblies arranged above and below the carrier plate assembly to radiantly heat the carrier plate assembly in a non-contact mode, provides high-efficiency and fast heating and uniform temperature distribution for the chips and the carrier plate, embeds the cooling pipes into the carrier plate assembly to directly contact and cool, greatly improves the cooling speed of the chips, and simultaneously considers the heating and cooling performance under the premise of certain power.

Description

Technical Field

[0001] This invention relates to the field of semiconductor chip welding technology, and in particular to a sealed cavity for semiconductor chip welding. Furthermore, this invention also relates to a vacuum eutectic furnace including the aforementioned sealed cavity for semiconductor chip welding. Background Technology

[0002] Vacuum eutectic bonding is an important welding process in microelectronic assembly, also known as low-melting-point alloy bonding. A eutectic alloy solder sheet is placed between the chip and the carrier, heated to the alloy's melting point in a protective atmosphere, and then cooled to form a eutectic alloy, thus completing the bonding between the chip and the carrier. Compared with traditional epoxy conductive adhesive bonding, eutectic bonding has advantages such as high thermal conductivity, low resistance, fast heat transfer, uniform heat dissipation, high reliability, good process consistency, and high shear force after bonding. It is suitable for high-frequency, high-power devices and welding applications with reliable component mounting requirements, such as the welding of power devices, hybrid integrated circuits, microwave RF devices, and MEMS devices.

[0003] The main components of a vacuum eutectic furnace include: a vacuum system, a sealed chamber, a reducing atmosphere system, a gas flow control system, a safety system, and a control system. The sealed chamber contains a heating module, a cooling module, a carrier board, and a process gas module. The entire chip soldering process is completed within the vacuum chamber; therefore, the design of the vacuum chamber is crucial to ensuring soldering quality.

[0004] Currently available vacuum eutectic furnaces have certain design limitations in their sealed chambers, often failing to simultaneously handle heating and cooling. The main reasons are as follows:

[0005] In existing technologies, there are two main approaches to the heating and cooling design of vacuum eutectic furnace chambers: the first is to use non-contact radiant heating to heat the carrier plate, then heat the welding components through the carrier plate, and finally cool the carrier plate using air cooling; the second is to use contact heating, where heating tubes and cooling water pipes are embedded in the carrier plate simultaneously. The heating tubes directly contact the carrier plate to heat it, and then coolant is introduced to cool the carrier plate. Both approaches have certain problems. The former has a fast heating speed, but air cooling results in a slow cooling rate; the latter requires embedding both heating tubes and water pipes in the carrier plate, leading to a larger carrier plate size, a larger heat load, and higher requirements for the heating tube power. Another problem is that the coolant in the contact water cooling method can remain in the cooling pipes of the carrier plate, affecting heating efficiency. Summary of the Invention

[0006] The technical problem to be solved by the present invention is: in order to solve the problems of low cooling efficiency or large volume and high heat load in the heating and cooling of the vacuum eutectic furnace cavity in the prior art, a sealed cavity for semiconductor chip welding is provided, and a vacuum eutectic furnace including the above-mentioned sealed cavity for semiconductor chip welding is provided.

[0007] The technical solution adopted by this invention to solve its technical problem is: a sealed cavity for semiconductor chip welding, comprising:

[0008] upper cavity;

[0009] The lower cavity is disposed opposite to the upper cavity, and the upper cavity and the lower cavity form a sealed cavity between them when closed;

[0010] A carrier assembly, disposed within a sealed cavity, is used to place a chip. Heating components for radiative heating of the carrier assembly are disposed above and below the carrier assembly.

[0011] And a cooling assembly having a cooling pipe that runs through and is embedded inside the carrier assembly for introducing coolant to cool the carrier assembly.

[0012] This solution employs heating components installed above and below the carrier assembly for non-contact radiant heating, providing efficient and rapid heating and uniform temperature distribution for both the chip and the carrier assembly. Simultaneously, cooling pipes are embedded in the carrier assembly for direct contact cooling, significantly improving the chip cooling speed. Under the premise of a fixed power, both heating and cooling performance are taken into account.

[0013] To prevent the cooling pipes from not fitting tightly with the upper and lower plates due to thermal deformation, the carrier plate assembly further includes an upper plate and a lower plate located below it, with the cooling pipes distributed between the upper and lower plates.

[0014] Several elastic clamping components are provided between the upper plate and the lower plate. The elastic clamping components are used to elastically press the cooling pipe between the upper plate and the lower plate. This allows the upper plate and the lower plate to adaptively adjust to the thermal deformation of the cooling pipe under the action of elasticity, ensuring that the cooling pipe fits tightly with the upper plate and the lower plate, thereby improving cooling efficiency and service life.

[0015] To achieve elastic clamping of the cooling pipe, the elastic clamping assembly further includes an elastic expansion sleeve, a clamping guide shaft, and fasteners;

[0016] One of the upper plate and the lower plate is provided with a connection hole, and the other is connected to a fastener. The elastic expansion sleeve is disposed in the connection hole. One end of the pressing guide shaft has a pressure part, and the other end is inserted into the elastic expansion sleeve and connected to the fastener. The fastener is used to drive the pressing guide shaft to move in a direction away from the connection hole so that the pressure part presses the elastic expansion sleeve to expand radially outward, thereby tightening the elastic expansion sleeve in the connection hole.

[0017] In order to facilitate the expansion of the elastic sleeve in the radial direction by the pressure-applying part, the cross-sectional area of ​​the pressure-applying part gradually decreases along the direction from the connecting hole to the fastener.

[0018] To further improve the cooling rate, grooves matching the cooling pipes are formed on the lower surface of the upper plate and the upper surface of the lower plate, and the cooling pipes are embedded in the grooves of both the upper plate and the lower plate.

[0019] To further improve the cooling rate, the cooling pipes are multiple and spaced apart between the upper plate and the lower plate. The inlet of each cooling pipe is connected to the liquid inlet main pipe, and the outlet of each cooling pipe is connected to the liquid outlet main pipe.

[0020] Furthermore, both ends of the cooling pipe extend to the outside of the carrier plate assembly and are bent downward to form a connecting section. The connecting section at the inlet end of the cooling pipe is connected to the liquid inlet main pipe, and the connecting section at the outlet end of the cooling pipe is connected to the liquid outlet main pipe.

[0021] To address the issue of coolant affecting heating efficiency in the cooling pipe, a liquid inlet air blowing assembly is further included. The liquid inlet air blowing assembly includes a liquid inlet pipe, one end of which is connected to the main liquid inlet pipe, and the other end is unidirectionally connected to an air blowing connector and a liquid inlet connector.

[0022] To facilitate assembly and improve heating uniformity, the heating assembly further includes several heating tubes arranged at intervals, with the heating tubes of the heating assembly in the upper cavity and the heating tubes of the heating assembly in the lower cavity being distributed in a cross pattern.

[0023] The upper cavity has an upper inner cavity with an opening facing downwards. The heating tube of the heating component in the upper cavity passes through the upper inner cavity, and both ends of the heating tube are sealed and fixedly connected to the upper cavity.

[0024] The lower cavity has an upward-facing lower inner cavity, and the heating tube of the heating assembly in the lower cavity passes through the upper inner cavity, with both ends of the heating tube being sealed and fixedly connected to the lower cavity. The carrier plate assembly is fixed in the lower inner cavity.

[0025] To facilitate later maintenance of the heating element and extend its service life, the heating element further includes a heating zone and non-heating zones located at both ends of the heating zone;

[0026] The heating zone of the heating tube in the upper cavity is located in the upper inner cavity, and the non-heating zone of the heating tube in the upper cavity is located outside the upper inner cavity; the heating zone of the heating tube in the lower cavity is located in the lower inner cavity, and the non-heating zone of the heating tube in the lower cavity is located outside the lower inner cavity.

[0027] To improve heating efficiency and safety, an upper heat insulation component is further provided above the heating component in the upper cavity. The upper heat insulation component includes an upper heat insulation seat fixedly connected to the upper cavity and an upper reflector fixedly connected to the upper heat insulation seat. The upper reflector is located between the upper heat insulation seat and the heating component in the upper cavity.

[0028] A lower heat insulation component is provided below the heating component in the lower cavity. The lower heat insulation component includes a lower heat insulation seat fixedly connected to the lower cavity and a lower reflector fixedly connected to the lower heat insulation seat. The lower reflector is located between the lower heat insulation seat and the heating component in the lower cavity.

[0029] To further improve welding efficiency, a process air intake assembly is provided inside the sealed cavity. The process air intake assembly has several air distribution holes for introducing process atmosphere into the sealed cavity, and the air distribution holes are located above the carrier plate assembly.

[0030] To achieve automatic opening and closing, a driving device is further included, wherein the upper cavity and the lower cavity are hinged, and the driving device is used to drive the upper cavity and the lower cavity to rotate and open and close.

[0031] The present invention also provides a vacuum eutectic furnace, including the aforementioned sealed cavity for semiconductor chip welding.

[0032] The beneficial effects of the present invention are as follows: The sealed cavity for semiconductor chip welding of the present invention adopts heating components respectively set on the upper and lower parts of the carrier assembly to perform non-contact radiative heating, which provides efficient and fast heating and uniform temperature distribution for the chip and the carrier assembly. At the same time, the cooling pipe is embedded in the carrier assembly for direct contact cooling, which greatly improves the chip cooling speed. Under the premise of a certain power, both heating and cooling performance are taken into account. Attached Figure Description

[0033] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0034] Figure 1 This is a three-dimensional view of the sealed cavity for semiconductor chip welding of the present invention in the open state;

[0035] Figure 2 This is a cross-sectional view of the sealed cavity for semiconductor chip welding of the present invention in the open state;

[0036] Figure 3 This is a cross-sectional view of the sealed cavity for semiconductor chip welding of the present invention in the closed state;

[0037] Figure 4 This is an exploded view of the carrier plate assembly and cooling assembly of the present invention in action;

[0038] Figure 5 This is a three-dimensional schematic diagram of the carrier plate assembly and cooling assembly of the present invention in combination;

[0039] Figure 6 This is a cross-sectional schematic diagram of the carrier plate assembly and cooling assembly of the present invention in combination;

[0040] Figure 7 yes Figure 6 A magnified view of part A in the diagram;

[0041] Figure 8 This is a three-dimensional view of the clamping guide shaft and the elastic expansion sleeve of the present invention in action;

[0042] Figure 9 This is a three-dimensional view of the elastic expansion sleeve of the present invention;

[0043] Figure 10 This is a three-dimensional schematic diagram of the liquid inlet air blowing assembly of the present invention;

[0044] Figure 11 This is a schematic diagram of the heating element of the present invention;

[0045] Figure 12 This is a three-dimensional schematic diagram of the heating tube of the present invention installed in the upper cavity;

[0046] Figure 13 This is a schematic diagram of the observation window component of the present invention;

[0047] Figure 14 This is a bottom view schematic diagram of the heating tube of the present invention installed in the upper cavity;

[0048] Figure 15 yes Figure 14 Schematic diagram of the BB-direction section;

[0049] Figure 16 yes Figure 15 A magnified view of part of C;

[0050] Figure 17 This is a three-dimensional schematic diagram of the heating tube of the present invention installed in the lower cavity;

[0051] Figure 18 This is a top view schematic diagram of the heating tube of the present invention installed in the lower cavity;

[0052] Figure 19 yes Figure 18 Schematic diagram of cross-section along the DD direction;

[0053] Figure 20 yes Figure 19 A magnified view of part of E in the diagram;

[0054] Figure 21 This is a three-dimensional schematic diagram of the vacuum control component of the present invention.

[0055] In the diagram: 1. Upper cavity, 1-1. Upper inner cavity, 1-2. Upper heat insulation seat, 1-3. Upper reflector;

[0056] 2. Lower cavity; 2-1. Lower inner cavity; 2-2. Lower heat insulation seat; 2-3. Lower reflector; 2-4. Cavity sealing ring;

[0057] 3. Carrier board assembly; 3-1. Upper carrier board; 3-2. Lowering board; 3-3. Groove;

[0058] 4. Heating element; 4-1. Heating zone; 4-2. Non-heating zone;

[0059] 5. Cooling components; 5-1. Cooling pipes; 5-11. Connecting section; 5-2. Liquid inlet main pipe; 5-3. Liquid outlet main pipe;

[0060] 6. Elastic snap fastener assembly; 6-1. Elastic expansion sleeve; 6-11. Groove; 6-2. Pressing guide shaft; 6-21. Pressing part; 6-22. Threaded hole; 6-3. Fastener; 6-4. Connecting hole;

[0061] 7. Liquid inlet and air blowing assembly; 7-1. Liquid inlet pipe; 7-2. Air blowing connector; 7-3. Liquid inlet connector; 7-4. One-way valve; 7-5. T-connector.

[0062] 8. Process air intake assembly, 8-1. Air distribution port;

[0063] 9. Sealing assembly; 9-1. First sealing seat; 9-11. Sealing groove; 9-2. First sealing ring; 9-3. Second sealing seat; 9-4. Second sealing ring;

[0064] 10. Observation window assembly; 10-1. Observation window base; 10-2. Buffer pad; 10-3. Observation window glass; 10-4. Third sealing ring;

[0065] 11. Vacuum control components; 11-1. Vacuum piping; 11-2. Vacuum pressure sensor; 11-3. Vacuum baffle valve.

[0066] 12. Sealed cavity;

[0067] 13. Drive unit. Detailed Implementation

[0068] The invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention in a schematic manner. Therefore, they only show the components relevant to the invention, and the orientations and references (e.g., up, down, left, right, etc.) are only used to aid in the description of the features in the drawings. Therefore, the following specific embodiments are not intended to be limiting, and the scope of the claimed insulation subject matter is defined only by the appended claims and their equivalents.

[0069] like Figure 1-21 As shown, a sealed cavity for semiconductor chip welding includes:

[0070] Upper cavity 1;

[0071] The lower cavity 2 is positioned opposite the upper cavity 1. When closed, the upper cavity 1 and the lower cavity 2 form a sealed cavity 12 between them, such as... Figure 3 As shown;

[0072] Carrier assembly 3 is disposed in sealed cavity 12 for placing chip. Heating components for radiative heating are disposed above and below carrier assembly 3.

[0073] And a cooling assembly 5, having a cooling pipe 5-1 that runs through and is embedded inside the carrier plate assembly 3 for introducing coolant to cool the carrier plate assembly 3.

[0074] Regarding the specific structure of carrier assembly 3:

[0075] like Figure 4-6 As shown, the carrier plate assembly 3 includes an upper carrier plate 3-1 and a lower carrier plate 3-2 located below it. Cooling pipes 5-1 are distributed between the upper carrier plate 3-1 and the lower carrier plate 3-2, which facilitates manufacturing and assembly. In order to prevent the cooling pipes 5-1 from not fitting tightly with the upper carrier plate 3-1 and the lower carrier plate 3-2 due to thermal deformation, in this embodiment, several elastic clamping components 6 are provided between the upper carrier plate 3-1 and the lower carrier plate 3-2. The elastic clamping components 6 are used to elastically press the cooling pipes 5-1 between the upper carrier plate 3-1 and the lower carrier plate 3-2. Thus, the upper carrier plate 3-1 and the lower carrier plate 3-2 can adaptively adjust to the thermal deformation of the cooling pipes 5-1 under the action of elasticity, ensuring that the cooling pipes 5-1 fit tightly with the upper carrier plate 3-1 and the lower carrier plate 3-2, thereby improving cooling efficiency and service life.

[0076] like Figure 7-8As shown, the elastic buckle assembly 6 includes an elastic expansion sleeve 6-1, a pressing guide shaft 6-2, and a fastener 6-3; one of the upper plate 3-1 and the lower plate 3-2 is provided with a connecting hole 6-4, and the other is connected to the fastener 6-3. The elastic expansion sleeve 6-1 is disposed in the connecting hole 6-4. One end of the pressing guide shaft 6-2 has a pressing part 6-21, and the other end is inserted into the elastic expansion sleeve 6-1 and connected to the fastener 6-3. The fastener 6-3 is used to drive the pressing guide shaft 6-2 to move in a direction away from the connecting hole 6-4, so that the pressing part 6-21 presses the elastic expansion sleeve 6-1 to expand radially outward, thereby tightening the elastic expansion sleeve 6-1 in the connecting hole 6-4.

[0077] In other words, the connecting hole 6-4 can be opened on the lower surface of the upper plate 3-1, and the fastener 6-3 is connected to the download plate 3-2; or the connecting hole 6-4 can be opened on the upper surface of the download plate 3-2, and the fastener 6-3 is connected to the upper plate 3-1. Taking the connecting hole 6-4 being opened on the download plate 3-2 as an example, the pressure part 6-21 is located at the upper end of the clamping guide shaft 6-2, the lower end of the clamping guide shaft 6-2 is inserted into the elastic expansion sleeve 6-1 and connected to one end of the fastener 6-3, and the other end of the fastener 6-3 is connected to the download plate 3-2. When the fastener 6-3 drives the clamping guide shaft 6-2 to move downward... The pressure part 6-21 compresses the elastic expansion sleeve 6-1 to expand radially outward, thereby tightening the elastic expansion sleeve 6-1 within the connecting hole 6-4; in this embodiment, the fastener 6-3 can specifically be a screw, and a threaded hole 6-22 is provided in the clamping guide shaft 6-2. The threaded end of the screw is threadedly connected to the threaded hole 6-22, and the screw nut abuts against the lower surface of the download plate 3-2. When the screw is tightened, the clamping guide shaft 6-2 gradually moves downward. During this process, the outer diameter of the elastic expansion sleeve 6-1 also gradually expands, thereby fixing the upper plate 3-1 and the download plate 3-2 together and offsetting the thermal deformation of the cooling pipe 5-1;

[0078] In this embodiment, the cross-sectional area of ​​the pressure-applying part 6-21 gradually decreases along the direction from the connecting hole 6-4 to the fastener 6-3, which facilitates the pressure-applying part 6-21 driving the elastic expansion sleeve 6-1 to expand radially outward. Specifically, the pressure-applying part 6-21 can be a rotating body, with its generatrix inclined inward from bottom to top, for example... Figure 8 As shown, when the generatrix is ​​oblique, the pressure-applying part 6-21 becomes conical; to further facilitate the outward expansion of the elastic expansion sleeve 6-1, as... Figure 8 As shown, the elastic expansion sleeve 6-1 has multiple slots 6-11 spaced apart at one end near the pressure part 6-21.

[0079] like Figure 4 and 7As shown, in this embodiment, the lower surface of the upper carrier plate 3-1 and the upper surface of the lower carrier plate 3-2 are both provided with grooves 3-3 that match the cooling pipe 5-1. The cooling pipe 5-1 is embedded in the grooves 3-3 of both the upper carrier plate 3-1 and the lower carrier plate 3-2, thereby increasing the contact area between the cooling pipe 5-1 and the carrier plate assembly 3 and improving the cooling efficiency.

[0080] Regarding the specific structure of cooling component 5:

[0081] like Figure 4 As shown, there are multiple cooling pipes 5-1, which are arranged at intervals between the upper plate 3-1 and the lower plate 3-2. The inlet of the cooling pipe 5-1 is connected to the liquid inlet pipe 5-2, and the outlet of the cooling pipe 5-1 is connected to the liquid outlet pipe 5-3. The advantages of this structure are that the coolant is divided into several paths, which enter and exit at the same time. The part of the cooling pipe 5-1 between the upper plate 3-1 and the lower plate 3-2 is preferably a straight pipe. Compared with the existing design of one or two serpentine cooling pipes 5-1, this solution has low friction resistance, large flow rate, and faster and more uniform cooling speed. In this embodiment, the cooling pipes 5-1 can be arranged in parallel and distributed at equal intervals between the upper plate 3-1 and the lower plate 3-2.

[0082] like Figure 5 As shown, both ends of the cooling pipe 5-1 extend to the outside of the carrier plate assembly 3 and are bent downward to form a connecting section 5-11. The connecting section 5-11 at the inlet end of the cooling pipe 5-1 is connected to the liquid inlet main pipe 5-2, and the connecting section 5-11 at the outlet end of the cooling pipe 5-1 is connected to the liquid outlet main pipe 5-3.

[0083] like Figure 3 and 10 As shown, it also includes a liquid inlet air blowing assembly 7, which includes a liquid inlet pipe 7-1. One end of the liquid inlet pipe 7-1 is connected to the main liquid inlet pipe 5-2, and the other end is unidirectionally connected to an air blowing connector 7-2 and a liquid inlet connector 7-3. The liquid inlet air blowing assembly 7 can both introduce coolant into the cooling pipe 5-1 and drain the coolant in the cooling pipe 5-1, without affecting the heating efficiency of the carrier plate assembly 3. In this embodiment, the liquid inlet pipe 7-1 can be specifically connected to the air blowing connector 7-2 using a three-way pipe 7-5. The first end of the three-way pipe 7-5 is connected to the inlet pipe 7-1, and the second end of the three-way pipe 7-5 is connected to the air blower 7-2 through the one-way valve 7-4 to prevent the fluid in the inlet pipe 7-1 from flowing out through the inlet pipe 7-3. The third end of the three-way pipe 7-5 is connected to the air blower 7-2 through the one-way valve 7-4 to prevent the fluid in the inlet pipe 7-1 from flowing out through the air blower 7-2. This is to ensure that the coolant or gas flows in the specified direction and path when they are working separately.

[0084] Regarding the structure of the heating assembly:

[0085] like Figure 2 As shown, the heating assembly includes several heating tubes 4 arranged at intervals. The heating tubes 4 of the heating assembly in the upper cavity 1 and the heating tubes 4 of the heating assembly in the lower cavity 2 are arranged in a cross pattern, preferably in a vertical pattern, so as to improve the uniformity of heating.

[0086] like Figure 12-16 As shown, the upper cavity 1 has an upper inner cavity 1-1 with the opening facing downward. The heating tube 4 of the heating component in the upper cavity 1 passes through the upper inner cavity 1-1, and both ends of the heating tube 4 are respectively sealed and fixedly connected to the upper cavity 1 through the sealing component 9.

[0087] like Figure 17-20 As shown, the lower cavity 2 has an upward-facing lower inner cavity 2-1. The heating tube 4 of the heating assembly passes through the lower inner cavity 2-1, and both ends of the heating tube 4 are sealed and fixedly connected to the lower cavity 2 by sealing assemblies 9. The carrier plate assembly 3 is fixed in the lower inner cavity 2-1. In this embodiment, the sealing assembly 9 may specifically include: a first sealing seat 9-1, a first sealing ring 9-2, a second sealing seat 9-3, and a second sealing ring 9-4. The end of the heating tube 4 passes through the first sealing seat 9-1 and the second sealing seat 9-3. The second sealing seat 9-3 is located outside the first sealing seat 9-1 and is detachably fixed to the first sealing seat 9-1. The second sealing seat 9-3 is provided with a sealing groove 9-11 for embedding the second sealing ring 9-4. The second sealing ring 9-4 is pressed between the first sealing seat 9-1 and the second sealing seat 9-3, and the second sealing ring 9-4 hugs the heating tube 4. The second sealing seat 9-3 is fixed to the outside of the corresponding upper cavity 1 or lower cavity 2 and is pressed against the outer wall of the corresponding upper cavity 1 or lower cavity 2.

[0088] like Figure 11 The heating tube 4 has a heating zone 4-1 and non-heating zones 4-2 located at both ends of the heating zone 4-1. The heating zone 4-1 of the heating tube 4 in the upper cavity 1 is located in the upper inner cavity 1-1, and the non-heating zone 4-2 of the heating tube 4 in the upper cavity 1 passes through the corresponding sealing component 9 and extends out of the upper inner cavity 1-1. The heating zone 4-1 of the heating tube 4 in the lower cavity 2 is located in the lower inner cavity 2-1, and the non-heating zone 4-2 of the heating tube 4 in the lower cavity 2 passes through the corresponding sealing component 9 and extends out of the upper inner cavity 1-1. With the above structure, on the one hand, when installing and replacing the heating tube 4, the sealing and wiring are all performed outside the upper cavity 1 and the lower cavity 2, which is very convenient. On the other hand, the non-heating zone 4-2 is located at the sealing connection of the upper cavity 1 or the lower cavity 2 and is located outside the upper cavity 1 and the lower cavity 2. It has a low temperature and no oxide corrosion, which increases the service life of the heating tube 4.

[0089] Regarding the structure of the upper cavity 1 and the lower cavity 2:

[0090] To improve heating efficiency and safety, an upper heat insulation component is provided above the heating component in the upper cavity 1. The upper heat insulation component includes an upper heat insulation seat 1-2 fixedly connected to the upper cavity 1 and an upper reflector 1-3 fixedly connected to the upper heat insulation seat 1-2. The upper reflector 1-3 is located between the upper heat insulation seat 1-2 and the heating component in the upper cavity 1. Specifically, the lower end of the upper heat insulation seat 1-2 can be a groove structure that is recessed upwards. The bottom of the groove and the surrounding side walls of the lower end of the upper heat insulation seat 1-2 are covered with corresponding upper reflectors 1-3. The upper reflectors 1-3 are used to block and reflect the light of the heating tube 4, so that the heat of the heating tube 4 is more concentrated and the heating efficiency of the heating component in the upper cavity 1 to the carrier plate component 3 is improved.

[0091] like Figure 13 As shown, an observation window assembly 10 is provided on the outer side of the top of the upper cavity 1. Observation holes are provided in the upper cavity 1, the upper heat insulation seat 1-2, and the upper reflector 1-3. The observation holes of the upper cavity 1, the upper heat insulation seat 1-2, and the upper reflector 1-3 are coaxially arranged. The observation window assembly 10 includes a window base 10-1, a buffer pad 10-2, a window glass 10-3, and a third sealing ring 10-4. The window base 10-1 presses the window glass 10-3 and presses the third sealing ring 10-4 on the top of the upper cavity 1 to achieve a seal. The window glass 10-3 is directly opposite the observation hole. The buffer pad 10-2 is placed between the window base 10-1 and the window glass 10-3 to provide a buffering effect.

[0092] A lower heat insulation component is provided below the heating component in the lower cavity 2. The lower heat insulation component includes a lower heat insulation seat 2-2 fixedly connected to the lower cavity 2 and a lower reflector 2-3 fixedly connected to the lower heat insulation seat 2-2. The lower reflector 2-3 is located between the lower heat insulation seat 2-2 and the heating component in the lower cavity 2. Specifically, the upper end of the lower heat insulation seat 2-2 can be a downwardly recessed groove structure. The bottom of the groove and the surrounding side walls of the upper heat insulation seat 1-2 are covered with corresponding lower reflectors 2-3. The lower reflectors 2-3 are used to block and reflect the light of the heating tube 4, so that the heat of the heating tube 4 is more concentrated and the heating efficiency of the heating component in the lower cavity 2 to the carrier plate assembly 3 is improved. The upper heat insulation seat 1-2, the upper reflector 1-3, the lower heat insulation seat 2-2, and the lower reflector 2-3 are respectively provided with holes or groove structures for the heating tube 4 to pass through.

[0093] The lower cavity 2 is equipped with a liquid inlet, a liquid outlet, a process gas interface, and a vacuum port;

[0094] The inlet is connected to the inlet structure, and the outlet is connected to the outlet manifold.

[0095] like Figure 1As shown, the process gas interface is connected to the inlet of the process gas inlet assembly 8. The process gas inlet assembly 8 is provided inside the sealed cavity 12. The inlet of the process gas inlet assembly 8 is connected to the process gas interface. The process gas inlet assembly 8 has several gas distribution holes 8-1 for introducing process atmosphere into the sealed cavity 12. The gas distribution holes 8-1 are located above the carrier assembly 3. There are no less than two sets of process gas inlet assemblies 8. One set is used to introduce a mixed gas containing formic acid, and the other set is used to introduce other process gases. Compared with the prior art where the gas distribution holes 8-1 of the process gas inlet assembly 8 are located below the carrier, this scheme where the gas distribution holes 8-1 of the process gas inlet assembly 8 are located above the carrier assembly 3 has a better process atmosphere diffusion speed and distribution effect. The reason is that the chip is placed on the upper surface of the carrier assembly 3 for soldering. The process gas inlet assembly 8 is set above the carrier assembly 3. After the gas enters the sealed cavity 12 from the gas distribution holes 8-1, it can directly act on the chip soldering part without having to bypass the bottom of the carrier assembly 3 and completely fill the sealed cavity 12 before it can act.

[0096] like Figure 21 As shown, the vacuum port and the sealed cavity 12 are connected and sealed to the vacuum control component 11. The vacuum control component 11 includes a vacuum pipeline 11-1, a vacuum pressure sensor 11-2 and a vacuum baffle valve 11-3 arranged in series. The vacuum port is connected to a vacuum pump. The vacuum pressure sensor 11-2 is used to detect the pressure of the sealed cavity 12. The vacuum baffle valve 11-3 is used to control the opening and closing of the sealed cavity 12.

[0097] like Figure 1-3 As shown, this embodiment also includes a driving device 13. The upper cavity 1 and the lower cavity 2 are hinged together. The driving device 13 is used to drive the upper cavity 1 and the lower cavity 2 to rotate and open and close. When the upper cavity 1 and the lower cavity 2 are closed, a sealed cavity 12 is formed between the upper inner cavity 1-1 and the lower inner cavity 2-1. In order to improve the sealing effect, a sealing groove 3-3 is provided on the upper end face of the lower cavity 2. A cavity sealing ring 2-4 is installed in the sealing groove 3-3. When the upper cavity 1 and the lower cavity 2 are closed, the cavity sealing ring 2-4 is pressed to ensure a tight seal. The sealing performance of the sealing cavity 12; the sealing groove 3-3 can be a trapezoidal sealing groove, which has a better fixing and sealing effect on the cavity sealing ring 2-4 than the trapezoidal sealing groove; in this embodiment, the driving device 13 can be a linear reciprocating motion mechanism such as a cylinder and an electric push rod. Taking the electric push rod as an example, one end of the electric push rod is hinged to the upper cavity 1, and the other end is hinged to the lower cavity 2. A sensor can be installed on the side of the upper cavity 1 or the lower cavity 2 to detect whether the upper cavity 1 and the lower cavity 2 are closed in place.

[0098] In this embodiment, the sealed cavity for semiconductor chip welding operates by first placing the chip to be welded on the upper surface of the upper carrier plate 3-1. An electric push rod drives the upper cavity 1 and lower cavity 2 to automatically close and seal. Then, a vacuum is drawn, and the heating tube 4 is turned on. During the process, different process atmospheres, heating temperature parameters, and operating procedures are set according to different process requirements until welding is completed. The heating tube 4 then stops heating, and coolant is introduced into the cooling tube 5-1 to rapidly cool the carrier plate assembly 3, thereby rapidly cooling the chip. After cooling, compressed air is introduced through the air blower 7-2 to discharge any residual coolant from the cooling tube 5-1, ending the process. This invention provides a sealed cavity for semiconductor chip welding with a simple heating and cooling structure, convenient installation, and non-contact radiant heating, providing efficient and rapid heating and uniform temperature distribution for the chip and carrier plate assembly 3. Simultaneously, multiple sets of parallel cooling tubes 5-1 are embedded in the carrier plate assembly 3 for direct contact cooling, greatly improving the chip cooling speed. Under the premise of a certain power, both heating and cooling performance are considered.

[0099] Example 2

[0100] The present invention also provides a vacuum eutectic furnace, including the sealed cavity for semiconductor chip welding described in Embodiment 1 above.

[0101] The above description, based on the preferred embodiments of the present invention, provides inspiration. Those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification but must be determined according to the claims.

Claims

1. A sealed cavity for semiconductor chip welding, characterized in that: include: Upper cavity (1); The lower cavity (2) is disposed opposite to the upper cavity (1), and the upper cavity (1) and the lower cavity (2) form a sealed cavity (12) between them when closed. The carrier assembly (3) is disposed in the sealed cavity (12) for placing the chip. Heating components for radiative heating are disposed above and below the carrier assembly (3). And a cooling assembly (5), having a cooling pipe (5-1) that runs through and is embedded inside the carrier assembly (3) for introducing coolant to cool the carrier assembly (3). The carrier plate assembly (3) includes an upper carrier plate (3-1) and a lower carrier plate (3-2) located below it, and the cooling pipe (5-1) is distributed between the upper carrier plate (3-1) and the lower carrier plate (3-2); A plurality of elastic snap fasteners (6) are provided between the upper plate (3-1) and the lower plate (3-2). The elastic snap fasteners (6) are used to elastically press the cooling pipe (5-1) between the upper plate (3-1) and the lower plate (3-2). The elastic snap fastener assembly (6) includes an elastic expansion sleeve (6-1), a pressing guide shaft (6-2), and a fastener (6-3). One of the upper plate (3-1) and the lower plate (3-2) is provided with a connecting hole (6-4), and the other is connected to a fastener (6-3). An elastic expansion sleeve (6-1) is disposed in the connecting hole (6-4). One end of the pressing guide shaft (6-2) has a pressure part (6-21), and the other end is inserted into the elastic expansion sleeve (6-1) and connected to the fastener (6-3). The fastener (6-3) is used to drive the pressing guide shaft (6-2) to move away from the connecting hole (6-4) so ​​that the pressure part (6-21) presses the elastic expansion sleeve (6-1) to expand radially outward, thereby tightening the elastic expansion sleeve (6-1) in the connecting hole (6-4). The cooling pipes (5-1) are multiple and are arranged at intervals between the upper plate (3-1) and the lower plate (3-2). The inlet of the cooling pipe (5-1) is connected to the liquid inlet pipe (5-2), and the outlet of the cooling pipe (5-1) is connected to the liquid outlet pipe (5-3).

2. The sealed cavity for semiconductor chip welding according to claim 1, characterized in that: The cross-sectional area of ​​the pressure-applying part (6-21) gradually decreases along the direction from the connecting hole (6-4) to the fastener (6-3).

3. The sealed cavity for semiconductor chip welding according to claim 1, characterized in that: The lower surface of the upper plate (3-1) and the upper surface of the lower plate (3-2) are both provided with grooves (3-3) that match the cooling pipe (5-1), and the cooling pipe (5-1) is embedded in the grooves (3-3) of both the upper plate (3-1) and the lower plate (3-2).

4. The sealed cavity for semiconductor chip welding according to claim 1, characterized in that: Both ends of the cooling pipe (5-1) extend to the outside of the carrier plate assembly (3) and are bent downward to form a connecting section (5-11). The connecting section (5-11) at the inlet end of the cooling pipe (5-1) is connected to the liquid inlet main pipe (5-2), and the connecting section (5-11) at the outlet end of the cooling pipe (5-1) is connected to the liquid outlet main pipe (5-3).

5. The sealed cavity for semiconductor chip welding according to claim 1, characterized in that: It also includes a liquid inlet air blowing assembly (7), which includes a liquid inlet pipe (7-1), one end of which is connected to the liquid inlet main pipe (5-2), and the other end is unidirectionally connected to an air blowing connector (7-2) and a liquid inlet connector (7-3).

6. The sealed cavity for semiconductor chip welding according to claim 1, characterized in that: The heating assembly includes several heating tubes (4) arranged at intervals. The heating tubes (4) of the heating assembly in the upper cavity (1) and the heating tubes (4) of the heating assembly in the lower cavity (2) are arranged in a cross pattern. The upper cavity (1) has an upper inner cavity (1-1) with the opening facing downward. The heating tube (4) of the heating component in the upper cavity (1) passes through the upper inner cavity (1-1), and both ends of the heating tube (4) are sealed and fixedly connected to the upper cavity (1). The lower cavity (2) has an upper inner cavity (2-1), the heating tube (4) of the heating component in the lower cavity (2) passes through the lower inner cavity (2-1), and both ends of the heating tube (4) are sealed and fixedly connected to the lower cavity (2), and the carrier plate assembly (3) is fixed in the lower inner cavity (2-1).

7. The sealed cavity for semiconductor chip welding according to claim 6, characterized in that: The heating tube (4) has a heating zone (4-1) and non-heating zones (4-2) located at both ends of the heating zone (4-1); The heating zone (4-1) of the heating tube (4) in the upper cavity (1) is located in the upper inner cavity (1-1), and the non-heating zone (4-2) of the heating tube (4) in the upper cavity (1) is located outside the upper inner cavity (1-1); the heating zone (4-1) of the heating tube (4) in the lower cavity (2) is located in the lower inner cavity (2-1), and the non-heating zone (4-2) of the heating tube (4) in the lower cavity (2) is located outside the lower inner cavity (2-1).

8. The sealed cavity for semiconductor chip welding according to claim 6, characterized in that: An upper heat insulation component is provided above the heating component in the upper cavity (1). The upper heat insulation component includes an upper heat insulation seat (1-2) fixedly connected to the upper cavity (1) and an upper reflector (1-3) fixedly connected to the upper heat insulation seat (1-2). The upper reflector (1-3) is located between the upper heat insulation seat (1-2) and the heating component of the upper cavity (1). A lower heat insulation component is provided below the heating component in the lower cavity (2). The lower heat insulation component includes a lower heat insulation seat (2-2) fixedly connected to the lower cavity (2) and a lower reflector (2-3) fixedly connected to the lower heat insulation seat (2-2). The lower reflector (2-3) is located between the lower heat insulation seat (2-2) and the heating component of the lower cavity (2).

9. The sealed cavity for semiconductor chip welding according to claim 1, characterized in that: The sealed cavity (12) is provided with a process air intake assembly (8), which has a plurality of air distribution holes (8-1) for introducing process atmosphere into the sealed cavity (12). The air distribution holes (8-1) are located above the carrier plate assembly (3).

10. The sealed cavity for semiconductor chip welding according to claim 1, characterized in that: It also includes a drive device (13), the upper cavity (1) and the lower cavity (2) are hinged together, and the drive device (13) is used to drive the upper cavity (1) and the lower cavity (2) to rotate and open and close.

11. A vacuum eutectic furnace, characterized in that; Includes a sealed cavity for semiconductor chip welding as described in any one of claims 1-10.

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