Multi-ram sintering apparatus and sintering method

Abstract

The application relates to the technical field of chip sintering, in particular to a multi-press-rod sintering device and a sintering method. The multi-press-rod sintering device comprises a first module and a second module. The first module is provided with a piston plate, a first heat insulation plate and a first template, and the first heat insulation plate is arranged between the piston plate and the first template. In the application, the piston transmits pressure to the press rod by using a force transmission element. Compared with a disconnected design, the heat on the press rod is not directly transmitted to the piston, the force transmission element has the effects of heat insulation and force transmission, the working condition of the piston is improved, and the piston is far away from the sintering cavity due to the arrangement of the force transmission element, so that the sealing property of the piston is not affected by the uneven heating of different materials due to different expansion coefficients. The heat insulation plate can insulate the heat transmission between the first template and the piston plate, and the sealing property of the piston is not affected by the high temperature.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of chip sintering, in particular to a multi-pressure-rod sintering device and a sintering method. BACKGROUND

[0002] The third generation of semiconductors represented by SiC and GaN is rising in strength, and the power chip market continues to increase. The power density and working environment temperature are getting higher and higher, which puts higher requirements on the upstream primary packaging process and heat dissipation materials. The traditional tin-based solder and conductive adhesive process has reached the application limit, and new processes need to be developed. The present application is a process for fixing chips using micron / nanometer metal silver / copper solder paste sintering. The principle is to apply a certain pressure under heating conditions of 150-300 DEG C to promote the necking and densification of micron / nanometer metal particles, and at the same time promote the volatilization of organic solvents in the micron / nanometer metal solder paste, and realize the mechanical and electrical connection of the chip and the substrate. The main application material is micron / nanometer silver paste or silver film. Micron / nanometer metal solder paste has the advantages of high melting point, good electrical conductivity and thermal conductivity, and green lead-free, and is suitable for interconnection of high power density chips. According to the existing technology and process, in addition to the sintering interconnection material, the control and uniformity of heating and pressurization during sintering are key indicators, and the structural design of the sintering equipment and the protective film design are important factors affecting this key indicator.

[0003] The heating and pressurization design of the existing sintering equipment mainly includes two categories: one is to use a heating dynamic pressure head, arrange multiple heating pressure heads on the upper mold, and arrange a film winding machine on the lower mold. The upper and lower movements of the film winding machine make the protective film coated on the lower mold. The lower mold must be designed as a concave type to ensure that the film and the edge of the lower mold form a closed area. The protective film is a kind of expensive consumables, which must be fully covered with the lower fixture, which inevitably increases the consumption of the film, and the upper and lower movement mechanism of the film winding mechanism is redundant. In addition, the heat of the heating plate is conducted to the upper sealing ring, which is easy to cause the aging failure of the sealing ring; the other is that the upper pressure head uses air bag pressure, the lower mold is divided into many parts, corresponding to the upper pressure head and coaxial, and the lower pressure head is heated at the upper part and cooled at the lower part.

[0004] In order to solve the above problems, the present application provides a multi-pressure-rod heating and pressurizing equipment for metal particle sintering. The present application adopts multiple layers of metal plates and force transmission members to avoid heating of the sealing area related to the piston, and the protective film does not need to fully cover the fixture according to the product. The pressure rod does not need to be reset, and the through hole machining precision on the flat plate is low, thereby reducing the cost. The preheating, sintering and cooling processes are carried out in turn, which is efficient and low in production cost. SUMMARY

[0005] The technical problem solved by the present application is: in order to solve the deficiencies in the prior art, the present application provides a multi-press rod sintering device and a sintering method.

[0006] The technical scheme adopted by the present application to solve its technical problem is: a multi-press rod sintering device, comprising a first module and a second module:

[0007] The first module has a piston plate, a first heat insulation plate and a first template, and the first module and the second module are arranged to be relatively close to form a sintering cavity between the first template and the second module, and the first heat insulation plate is arranged between the piston plate and the first template;

[0008] A plurality of press rods are movably installed on the first template, and the piston plate has one or more pistons, which are arranged to be movable under the action of fluid and to drive the press rods to move through a force transmission member for heat insulation or in turn through a plurality of force transmission members for heat insulation, so that the press rods exert pressure on the products in the sintering cavity;

[0009] The first template or / and the second module is provided with a heating assembly for heating the products in the sintering cavity.

[0010] In this scheme, the piston transmits pressure to the press rod through the force transmission member, which avoids direct transmission of heat on the press rod to the piston, and the force transmission member plays the role of heat insulation and force transmission, improving the working condition of the piston. At the same time, due to the arrangement of the force transmission member, the piston can be away from the sintering cavity, which can avoid the influence of different materials due to different expansion coefficients and uneven heating on the sealing performance of the piston. The heat insulation plate can insulate the heat transfer between the first template and the piston plate, and avoid the influence of high temperature on the sealing performance of the piston.

[0011] In order to reduce the heat transfer between the first template and the force transmission member, further, a plurality of through holes are formed in the first heat insulation plate, and the force transmission member is arranged in the through hole.

[0012] In order to realize the heat insulation between the piston and the press rod, further, the force transmission member between the piston and the press rod driven by the piston has one, the contact area between the piston and the force transmission member is contact area A, the contact area between the force transmission member and the press rod is contact area B, and at least one of contact area A and contact area B is smaller than the maximum cross-sectional area of the force transmission member;

[0013] Or the force transmission member between the piston and the press rod driven by the piston has a plurality of, the contact area between the piston and the force transmission member is contact area A, the contact area between the force transmission member and the press rod is contact area A, and the contact area between the adjacent two force transmission members is contact area C. At least one of contact area A, contact area B and contact area C is smaller than the maximum cross-sectional area of the force transmission member.

[0014] In order to reduce the contact area while ensuring the mechanical strength of the force transmission member, further, the force transmission member has a heat insulation section at one end in the moving direction of the piston or at both ends, the heat insulation section has a large cross-sectional area at one end and a small cross-sectional area at the other end, and the end with the large cross-sectional area is fixedly connected to the force transmission member or integrally formed.

[0015] In order to facilitate manufacturing, further, the heat insulation section is conical, hemispherical or spherical.

[0016] In order to prevent the force transmission member from being affected by the first heat insulation plate due to lateral force caused by the gap, further, a bushing is arranged between the through hole of the first heat insulation plate and the force transmission member, the force transmission member is slidingly installed in the corresponding bushing, and the sliding direction of the force transmission member is parallel to the moving direction of the piston.

[0017] In order to block the direct heat transfer from the first mold plate to the force transmission member after heating, thereby avoiding excessive thermal load on the piston, further, the force transmission member in contact with the pressure rod is not in contact with the first mold plate.

[0018] In order to prevent the pressure rod from rotating and affecting the sintering quality of the product, further, the pressure rod is slidingly installed on the first mold plate in the moving direction of the piston, and the pressure rod is fixedly connected to the first mold plate in the circumferential direction.

[0019] In order to facilitate manufacturing and assembly, further, a plurality of grooves are arranged on the end face of the first mold plate close to the first heat insulation plate, a plurality of pressure rod holes matched with the pressure rod are arranged on the groove bottom of each groove, the pressure rod and the pressure rod hole are one-to-one corresponding, and the pressure rod is slidingly installed in the corresponding pressure rod hole; the end of the pressure rod close to the groove has a head portion for contacting the force transmission member, the outer peripheral wall of the head portion has a limiting surface, the head portion of the pressure rod is located in the groove, and the limiting surface is in contact with the groove wall to prevent the pressure rod from rotating; the end of the head portion close to the second mold has a stepped surface for preventing the head portion from entering the pressure rod hole.

[0020] In order to improve the heat insulation effect, further, when the force transmission member in contact with the pressure rod extends into the groove, there is a gap between the groove wall to form a heat insulation zone.

[0021] In order to reduce the number of components and facilitate assembly, further, each piston corresponds to a plurality of pressure rods, and one force transmission member or a plurality of force transmission members arranged in sequence in the moving direction of the piston is arranged between each pressure rod and the corresponding piston.

[0022] Alternatively, in order to facilitate synchronous pressure control, further, the pressure rod corresponds to the piston one-to-one, and one force transmission member or a plurality of force transmission members arranged in sequence in the moving direction of the piston is arranged between each pressure rod and the corresponding piston.

[0023] In order to facilitate the synchronous pressure control of the pressing rods, further, the piston has a high-pressure chamber on the side away from the first heat insulation plate, a plurality of piston holes are formed on the piston plate, the piston corresponds to the piston hole, the piston is slidably mounted in the corresponding piston hole, the high-pressure chamber is communicated with a medium flow port, and the hole of the piston hole on the side away from the first heat insulation plate is communicated with the high-pressure chamber.

[0024] In order to facilitate manufacturing and assembly, further, the piston plate is sealingly fixed with a cover plate on the side away from the first heat insulation plate, the high-pressure chamber is formed between the piston plate, the piston and the cover plate, and the hole of the piston hole on the side away from the first heat insulation plate extends into the high-pressure chamber.

[0025] In order to realize safe gas supply to the high-pressure chamber, further, a gas supply device is further included, the gas supply device includes a control gas path, a pressure regulating valve, a gas booster and a working gas path;

[0026] The pressure regulating valve is connected in series on the control gas path, the inlet of the control gas path is used to connect a control gas source, and the outlet of the control gas path is communicated with the gas booster;

[0027] The gas booster is connected in series on the working gas path, the inlet of the working gas path is used to connect a working gas source, and the outlet of the working gas path is communicated with the medium flow port of the high-pressure chamber;

[0028] The control gas path is used to provide power for the gas booster, so that the gas flowing into the gas booster in the working gas path is pressurized.

[0029] A sintering method based on the above-mentioned multi-pressing rod sintering device, comprising the following steps:

[0030] S1, placing the product to be sintered on the second module, heating the heating assembly, and placing the film material between the pressing rod and the product by the film rolling mechanism;

[0031] S2, moving the second module to the direction of approaching the first module;

[0032] S3, after the product contacts the film material, continue to move to the first module direction, after the pressing rod contacts the film material, move a certain distance upward to form a sintering chamber;

[0033] S4, locking the first module and the second module;

[0034] S5, introducing high-pressure gas, the piston applies force to the second module, and the product is pressurized through the force transmission column, the pressing rod and the film material;

[0035] S6, heating, while pressurizing, introducing sintering-promoting gas into the sintering chamber;

[0036] S7, then sintering cavity vacuum pumping out volatile gases during sintering, and then backfilling nitrogen to the sintering cavity to separate the film material from the second module;

[0037] S8, the piston decompression, the second module moves away from the first module, and the sintered product is transferred to the cooling area with the second module for cooling, completing a sintering cycle.

[0038] The beneficial effects of the present application are: the piston of the multi-press-rod sintering device utilizes the force transmission member to transmit the pressure to the pressure rod, which, compared with the disconnected design, avoids the direct transmission of heat on the pressure rod to the piston, the force transmission member plays the effect of heat insulation and force transmission, and the working condition of the piston is improved, and meanwhile, due to the arrangement of the force transmission member, the piston can be away from the sintering cavity, the sealing property of the piston can be avoided to be affected by the uneven heating of different materials due to different expansion coefficients, the heat insulation plate can insulate the heat transmission between the first template and the piston plate, the sealing property of the piston can be avoided to be affected by the excessively high temperature, and then the adverse effect on the pressure sintering effect can be avoided. BRIEF DESCRIPTION OF DRAWINGS

[0039] The present application will be further described below in combination with the drawings and examples.

[0040] Figure 1 is a three-dimensional schematic view of the multi-press-rod sintering device of the present application;

[0041] Figure 2 is a sectional view of the multi-press-rod sintering device of the present application;

[0042] Figure 3 is Figure 2 is a partial enlarged view of A in FIG. 4;

[0043] Figure 4 is Figure 2 is a partial enlarged view of B in FIG. 4;

[0044] Figure 5 is a schematic view of the sintering cavity in the present application;

[0045] Figure 6 is a three-dimensional schematic view of the piston plate and the piston after assembly;

[0046] Figure 7 is a three-dimensional schematic view of the first template and the pressure rod after assembly;

[0047] Figure 8 is a top view schematic view of the first template and the pressure rod after assembly;

[0048] Figure 9 is a three-dimensional schematic view of the pressure rod;

[0049] Figure 10 is a schematic view of the gas supply device;

[0050] Figure 11 This is a schematic diagram of a sandwich structure.

[0051] In the diagram: 1. First module; 11. First template; 111. Groove; 111a. Insulation zone; 112. Pressure rod hole; 113. Process atmosphere connection port; 12. First insulation plate; 121. Through hole; 13. Piston plate; 131. Piston hole; 132. Lower recess; 14. Cover plate; 15. Pressure rod; 151. Head; 151a. Limiting surface; 151b. Stepped surface; 16. Piston; 161. Piston sealing ring; 17. Force transmission component; 171. Insulation section; 18. Bushing; 19. High pressure chamber; 191. Medium flow port; 192. Sealing ring;

[0052] 2. Second module; 21. Second template; 22. Second insulation board; 23. Base plate;

[0053] 3. Film winding mechanism: 31. Membrane material, 32. Film roll take-up, 33. Film roll unwinding;

[0054] 4. Sintering cavity;

[0055] 5. Heating assembly; 51. Heating core;

[0056] 6. Gas supply device; 61. Control gas circuit; 62. Pressure regulating valve; 63. Gas booster; 64. Working gas circuit.

[0057] 7. Guiding mechanism; 71. Head plate; 72. Tail plate;

[0058] 8. Fixtures;

[0059] 9. Product; 91. Chip; 92. Sintered layer; 93. Substrate. Detailed Implementation

[0060] 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 subject matter is defined solely by the appended claims and their equivalents.

[0061] Example 1

[0062] like Figures 1-5 As shown, a multi-pressure bar sintering apparatus includes a head plate 71, a first module 1, a second module 2, and a film winding mechanism 3; the first module 1 and the second module 2 can be arranged horizontally or vertically. In this embodiment, the first module 1 and the second module 2 are arranged vertically, with the first module 1 located above the second module 2.

[0063] The first module 1 has a piston plate 13, a first heat insulation plate 12 and a first template 11. The first module 1 and the second module 2 are arranged to be able to approach each other to form a sintering cavity 4 between the first template 11 and the second module 2. The first heat insulation plate 12 is disposed between the piston plate 13 and the first template 11.

[0064] Multiple pressure rods 15 are movably mounted on the first template 11. The film winding mechanism 3 provides a film 31 between the pressure rods 15 and the product 9 in the sintering chamber 4. The piston plate 13 has one or more pistons 16, which are configured to move under fluid action and drive the pressure rods 15 to move via a heat-insulating force transmission member 17 or in sequence via multiple heat-insulating force transmission members 17, so that the pressure rods 15 apply pressure to the product 9 in the sintering chamber 4 through the film 31; Figure 11 As shown, product 9 in this embodiment can specifically be a sandwich structure composed of chip 91, sintering layer 92 and substrate 93 arranged from top to bottom; it is worth noting that in this embodiment, "multiple" refers to two or more.

[0065] The first template 11 and / or the second module 2 are provided with a heating component 5 for heating the product 9 in the sintering chamber 4.

[0066] In this embodiment, the head plate 71 is made of metal, such as steel. The head plate 71 is locked onto the guide mechanism 7. The guide mechanism can be a tie rod, linear guide rail, etc. The head plate 71 is used to fix the first module 1.

[0067] like Figure 3 As shown, regarding the structure of the force transmission component 17: the force transmission component 17 is a metal force transmission component 17; there are one or more force transmission components 17 between the piston 16 and the pressure rod 15 driven by it. In this embodiment, multiple force transmission components 17 are used between the piston 16 and the pressure rod 15 driven by it, such as two. That is, two force transmission components 17 are used on the power transmission path between the piston 16 and the pressure rod 15. The contact area between the piston 16 and the force transmission component 17 is the contact area A, the contact area between the force transmission component 17 and the pressure rod 15 is the contact area B, and the contact area between two adjacent force transmission components 17 is the contact area C. At least one of the contact areas A, B, and C is smaller than the maximum cross-sectional area of ​​the force transmission component 17.

[0068] Therefore, the heat insulation effect can be controlled by controlling the areas of the contact area A, the contact area B and the contact area C. Specifically, one end of the force transmission member 17 in the moving direction of the piston 16 has a heat insulation section 171 or both ends have the heat insulation section 171, the cross-sectional area of one end of the heat insulation section 171 is larger than that of the other end, and the one end of the heat insulation section 171 is fixedly connected or integrally formed with the force transmission member 17. In this way, the heat insulation section 171 can be designed to have a gradually tapered structure, for example, a conical, hemispherical or spherical cap shape, so as to reduce the contact area A and / or the contact area B and / or the contact area C while considering the mechanical strength of the force transmission member 17. Of course, the heat insulation section 171 can also be a solid structure with a large cross-sectional area at one end and a hollow ring structure with a small cross-sectional area at the other end. In this embodiment, the cross section of the force transmission member 17 is circular, the heat insulation section 171 is hemispherical, the heat insulation section 171 is coaxially arranged with the force transmission member 17, and the maximum cross-sectional area of the force transmission member 17 is equal to the cross-sectional area of the force transmission member 17. The piston plate 13 does not contact the first mold plate 11 which is at a high temperature due to heating, and the spherical surface of the end surface of the force transmission member 17 reduces heat transfer, so that the sealing member of the piston 16 is not subjected to high temperature baking and aging.

[0069] Regarding the layout of the force transmission member 17, a plurality of through holes 121, such as circular through holes 121, are formed in the first heat insulation plate 12, and the force transmission member 17 is arranged in the through holes 121 to reduce heat transfer between the first mold plate 11 and the outer peripheral wall of the force transmission member 17. It is ensured that the force transmission member 17 does not contact the first mold plate 11 to prevent the heat on the first mold plate 11 from being directly transferred to the pressure rod 15. In order to prevent the force transmission member 17 from affecting the first heat insulation plate 12 due to lateral force caused by the gap, a bushing 18 is arranged between the force transmission member 17 and the through holes 121 of the first heat insulation plate 12, the force transmission member 17 is slidingly installed in the bushing 18 corresponding thereto, and the sliding direction of the force transmission member 17 is parallel to the moving direction of the piston 16. The bushings 18 are preferably designed not to contact each other and not to contact the first mold plate 11, so as to avoid a large amount of heat being transferred to the force transmission member 17 through the bushings 18.

[0070] As shown in FIGS. Figure 7 , 8 and 9, regarding the layout of the pressure rod 15, the pressure rod 15 is slidingly installed on the first mold plate 11 in the moving direction of the piston 16, and the pressure rod 15 is fixedly connected with the first mold plate 11 in the circumferential direction. The circumferential fixation limits the rotation of the pressure rod 15 in the circumferential direction, so as to prevent the pressure rod 15 from affecting the sintering quality of the product 9 due to rotation.

[0071] The pressing rod 15 can be designed to have a non-circular cross section, such as a square or a D shape, and is inserted into the first mold plate 11 to achieve circumferential fixation of the pressing rod 15 to the first mold plate 11. For example, the first mold plate 11 is provided with a plurality of grooves 111 at an end surface near the first heat insulation plate 12, and each groove 111 is provided with a plurality of pressing rod holes 112 matched with the pressing rod 15, such as circular pressing rod holes 112. The pressing rod 15 is in one-to-one correspondence with the pressing rod holes 112 and is slidably installed in the corresponding pressing rod hole 112. The pressing rod 15 has a head 151 near the groove 111 for contact with the force transmitting member 17, and the outer peripheral wall of the head 151 is provided with a limiting surface 151a. The head 151 of the pressing rod 15 is located in the groove 111, and the limiting surface 151a is in contact with the groove wall of the groove 111 to prevent the pressing rod 15 from rotating, thereby achieving circumferential fixation of the pressing rod 15 to the first mold plate 11. In addition, the limiting surface 151a of the pressing rod 15 can be provided with a transition chamfer for easy up-and-down movement under the guidance of the first mold plate 11. In addition, the extension direction of the groove 111 and the matching shape of the limiting surface 151a of the head 151 of the pressing rod 15 can be adaptively adjusted and designed according to actual application requirements, and the present application is not limited to the arrangement shown in Figures 7-8 On this basis, a step surface 151b can be designed on the head 151 near the second module 2 to prevent the head 151 from entering the pressing rod hole 112. When the head 151 moves downward to contact the step surface 151b with the groove bottom of the groove 111, it can no longer continue to move downward, which is equivalent to the pressing rod 15 reaching the limit position of downward displacement, to prevent the pressing rod 15 from falling off the first mold plate 11 and damaging the product 9 to be sintered, and also to prevent the piston 16 from driving the pressing rod 15 to produce excessive displacement and damage the product 9 to be sintered. When the head 151 moves downward to contact the step surface 151b with the groove bottom of the groove 111, the pressing rod 15 protrudes downward from the first mold plate 11, for example, the pressing rod 15 protrudes downward from the first mold plate 11 by a distance of 0.1-1 mm, which can be adjusted according to actual application requirements.

[0072] The force transmitting member 17 in contact with the pressing rod 15 has a gap between the groove wall of the groove 111 when it extends into the groove 111 to form a heat insulation zone 111a, thereby improving the heat insulation effect.

[0073] It is worth noting that the through hole 121 on the first heat insulation plate 12 can be opened according to the distribution form of the pressing rod hole 112, so that the through hole 121 is in one-to-one correspondence with the pressing rod hole 112, and the through hole 121 and the corresponding pressing rod hole 112 can be coaxially arranged.

[0074] As to the arrangement of the pistons 16: a plurality of pistons 16 correspond to a plurality of pressure rods 15, and a force transmission member 17 is arranged between each pressure rod 15 and its corresponding piston 16 or a plurality of force transmission members 17 are arranged in sequence along the moving direction of the piston 16; or, in order to facilitate synchronous pressure control, the pressure rod 15 corresponds to the piston 16 one by one, and a force transmission member 17 is arranged between each pressure rod 15 and its corresponding piston 16 or a plurality of force transmission members 17 are arranged in sequence along the moving direction of the piston 16;

[0075] In the present embodiment, the piston 16 corresponds to the pressure rod 15 one by one, and in order to facilitate synchronous pressure control of the pressure rod 15, the piston 16 has a high-pressure chamber 19 on the side away from the first heat insulation plate 12, and a plurality of piston holes 131, such as circular cross-section piston holes 131, are formed on the piston plate 13, the number of which can be adjusted adaptively according to different products 9, and the piston 16 corresponds to the piston hole 131 one by one, and the piston 16 is sealingly and slidably installed in the corresponding piston hole 131, specifically, a piston sealing ring 161 is arranged between the outer peripheral wall of the piston 16 and the piston hole 131, the present technical solution places the piston 16 through the force transmission member 17, reduces the thermal load of the piston 16, and at the same time, avoids the aging of the piston sealing ring 161; more specifically, the piston sealing ring 161 can be embedded and fixed on the inner wall of the piston hole 131 or the outer peripheral wall of the piston 16; the high-pressure chamber 19 is communicated with a medium flow port 191, and the orifices on the side of the piston hole 131 away from the first heat insulation plate 12 are communicated with the high-pressure chamber 19; the pressure F1 is applied to the high-pressure chamber 19 in a closed area through external gas, all the pistons 16 are subjected to equal gas pressure and move downward, and the force transmission member 17 is pushed by the force F2, wherein F1 and F2 are in proportional relationship, thereby realizing synchronous pressure control of the plurality of pressure rods 15;

[0076] For the construction of the high-pressure chamber 19, the cover plate 14 is fixedly sealed to the side of the piston plate 13 away from the first heat insulation plate 12, and the high-pressure chamber 19 is formed between the piston plate 13, the piston 16 and the cover plate 14. For example, a recessed portion 132 is formed in the middle of the end face of the piston plate 13 away from the first heat insulation plate 12, and the depth of the recessed portion 132 is 1-10 mm. The orifices of the piston holes 131 on the side of the first heat insulation plate 12 extend into the recessed portion 132, and the high-pressure chamber 19 is formed between the recessed portion 132 of the piston plate 13, the piston 16 and the cover plate 14. Alternatively, a recessed portion is formed in the middle of the end face of the cover plate 14 close to the piston plate 13, and the depth of the recessed portion is 1-10 mm. The high-pressure chamber 19 is formed between the piston plate 13, the piston 16 and the recessed portion. Alternatively, a recessed portion is formed in the piston plate 13, and a recessed portion 132 is formed in the cover plate 14. The high-pressure chamber 19 is formed between the recessed portion 132, the piston 16 and the recessed portion. A sealing ring 192 is arranged between the piston plate 13 and the cover plate 14 and is sleeved outside the high-pressure chamber 19. The piston plate 13 or the cover plate 14 can be provided with a sealing groove, and the sealing ring 192 is embedded in the sealing groove.

[0077] As shown in Figure 10 , regarding the control of the high-pressure chamber 19: the gas supply device 6 is also included, and the gas supply device 6 includes a control gas path 61, a pressure regulating valve 62, a gas booster 63 and a working gas path 64.

[0078] The pressure regulating valve 62 is connected in series on the control gas path 61. The inlet of the control gas path 61 is used to connect a control gas source. The outlet of the control gas path 61 is in communication with the gas booster 63. In this embodiment, a filter, a flow sensor and a pressure gauge can also be arranged on the control gas path 61, and the filter, the flow sensor, the pressure regulating valve 62 and the pressure gauge are distributed in the flow direction of the gas in the control gas path 61.

[0079] The gas booster 63 is connected in series on the working gas path 64. The inlet of the working gas path 64 is used to connect a working gas source. The outlet of the working gas path 64 is in communication with the medium flow port 191 of the high-pressure chamber 19. In this embodiment, a filter, a flow sensor, a flow valve, an on-off valve, a pressure gauge and a pressure relief valve can also be arranged on the working gas path 64, and the filter, the flow sensor, the flow valve, the gas booster 63, the on-off valve, the pressure gauge and the pressure relief valve are distributed in the flow direction of the gas in the working gas path 64.

[0080] In this embodiment, the working gas source can adopt a compressed air source, and the working gas source adopts a nitrogen source. The compressed air provides power for the gas booster 63 through the control gas path 61, so that the nitrogen flowing into the gas booster 63 in the working gas path 64 is pressurized, and the pressurized nitrogen enters the high-pressure chamber 19.

[0081] The gas booster 63 is controlled by the pressure regulating valve 62, and the pressure of the high-pressure chamber 19 is controlled; when the high-pressure chamber 19 is depressurized, the switch valve is closed, and the pressure relief valve is opened, so as to reduce the gas pressure of the high-pressure chamber 19; the whole gas pressure adjustment process is relatively safer.

[0082] The piston plate 13, the first heat insulation plate 12 and the first template 11 are fixed together by fasteners, the cover plate 14 is fixedly connected with the head plate 71 by fasteners, and the cover plate 14 and the piston plate 13 can also be fixedly connected by fasteners.

[0083] In the embodiment, the diameter of the piston 16 can be equal to the diameter of the force transmission member 17, and the piston 16 and the corresponding pressure rod 15 are coaxially arranged, so that the force transmission member 17 can enter the piston hole 131, and the piston 16 can enter the bushing 18; it is worth noting that the number of the force transmission member 17 between the piston 16 and the corresponding pressure rod 15 in the embodiment is the same.

[0084] Regarding the second module 2, the second module 2 can specifically include the second template 21, the second heat insulation plate 22 and the bottom plate 23 fixed together, the second heat insulation plate 22 is located between the second template 21 and the bottom plate 23 to prevent heat conduction downward, the second template 21 is oppositely arranged with the first template 11, and the end face of the end of the second template 21 close to the first template 11 is used for placing the jig 8, the jig 8 is used for placing the semiconductor product 9 to be sintered, and the second template 21 or the first template 11 can be provided with a vacuum extraction opening communicated with the sintering cavity 4 and a process atmosphere communication opening 113 communicated with the sintering cavity 4, so as to facilitate the connection of the vacuum equipment to the sintering cavity 4 for vacuumizing;

[0085] The tail plate 72 is also locked on the guide mechanism 7, and the tail plate 72 is arranged between the bottom plate 23 and the execution mechanism for driving the second module 2 to approach or move away from the first module 1, and the execution mechanism can be an electric cylinder or a pneumatic cylinder, and taking the electric cylinder as an example, one end of the electric cylinder is connected to the tail plate 72, and the other end is connected to the bottom plate 23.

[0086] Regarding the heating assembly 5, the first template 11 and the second template 21 are both provided with the heating assembly 5, and a temperature sensor can also be arranged to monitor the heating temperature, the heating assembly 5 can adopt the existing technology or the existing heating assembly 5 with the same function, and an example provided in the embodiment is that the heating assembly 5 on the first template 11 adopts a plurality of electric heating cores 51 spaced apart in the first template 11, the heating assembly 5 on the second template 21 adopts a plurality of electric heating cores 51 spaced apart in the second template 21, and the point heating cores 51 on the first template 11 can be staggered with the electric heating cores 51 on the second template 21.

[0087] Regarding the film winding mechanism 3, the prior art or the prior art film winding mechanism 3 can be used to achieve the same function. An example provided in this embodiment includes a film winding roll 32 and a film unwinding roll 33, which are respectively located on the left and right sides of the first module 1. One end of the film material 31 is wound on the film winding roll 32, and the other end is wound on the film unwinding roll 33. The film material 31 passes through the first template 11 and the second template 21, and is covered between the pressing rod 15 and the product 9 for heat conduction, anti-fouling, and buffer to compensate for the height difference of the chip 91. With the rotation of the film winding roll 32 and the film unwinding roll 33, the film material 31 between the first template 11 and the second template 21 can be replaced. The material of the film material 31 can be Teflon or fluororubber. The width of the film material 31 is determined according to the position and number of the chip 91 in the jig 8.

[0088] In this embodiment, the cover plate 14, the piston plate 13, the first template 11, and the second template 21 can all be made of metal. The first heat insulation plate 12 and the second heat insulation plate 22 require a low thermal conductivity coefficient, for example, a high-temperature-resistant resin glass fiber plate.

[0089] It is worth noting that the arrangement of the pressing rod 15 of the first template 11 can be adjusted according to the distribution of the chip 91 on the substrate 93. Specifically, the pressing rod 15 corresponds to one chip 91 on the substrate 93, and each pressing rod 15 corresponds to one chip 91. The substrate 93 is placed on the second template 21 through the jig 8, and the pressing rod 15 is arranged opposite to one chip 91 when the first template 11 and the second template 21 form the sintering cavity 4.

[0090] This embodiment uses a stacked structure of multiple layers of plates in cooperation with the force transmission member 17 to avoid heating of the high-pressure chamber 19 and the piston 16. The film material 31 is determined according to the product 9, and does not need to fully cover the jig 8. The pressing rod 15 does not need to be reset, and the machining precision requirements of the pressing rod hole 112 on the first template 11 and the through hole 121 of the first heat insulation plate 12 are low, thereby reducing the cost.

[0091] A sintering method based on the above-described multi-pressing rod sintering device, comprising the following steps:

[0092] S1, placing the sandwich structure composed of the product 9 chip 91, the sintering layer 92, and the substrate 93 on the upper end of the second template 21 through the jig 8, heating the heating assembly 5, and winding the film material 31 between the pressing rod 15 and the product 9 by the film winding mechanism 3;

[0093] S2, driving the second module 2 to move towards the first module 1;

[0094] S3, after the product 9 contacts the film material 31, continue to move towards the first module 1, and after the pressing rod 15 contacts the film material 31, move a certain distance upwards to form the sintering cavity 4;

[0095] S4, locking the first module 1 and the second module 2;

[0096] S5, high-pressure gas is introduced, the piston 16 applies force to the second module 2 direction, and the product 9 is pressurized through the force transmission column, the pressure rod 15 and the film material 31;

[0097] S6, while the heating assembly 5 is heated and the pressure rod 15 is pressurized, the sintering-promoting gas is introduced into the sintering cavity 4 from the process atmosphere communication port 113; in this process, the lower mold plate transmits heat to the jig 8, and the sintering layer 92 material of the sandwich structure on the jig 8 is densified under the heating and pressurizing conditions of the upper pressure rod 15, at the same time, the film material 31 is covered between the pressure rod 15 and the chip 91 for heat conduction, anti-pollution and buffer compensation of the height difference of the chip 91;

[0098] S7, after a certain time, the sintering cavity 4 is evacuated to remove volatile gases during sintering, and then the sintering cavity 4 is backfilled with nitrogen to separate the film material 31 from the second module 2;

[0099] S8, the gas pressure of the high-pressure chamber 19 is reduced, the piston 16 is decompressed, the second module 2 moves away from the first module 1, the sintered product 9 is transferred to the cooling area with the second module 2 for cooling, and a sintering cycle is completed.

[0100] The sintering method in the application has high efficiency and low production cost.

[0101] The above ideal embodiments according to the application are for inspiration, and through the above description, relevant personnel can make various changes and modifications without deviating from the technical idea of the application. The technical scope of the application is not limited to the content in the specification, and the technical scope must be determined according to the scope of claims.

Claims

1. A multi-press-rod sintering apparatus characterized by comprising: The first module (1) and the second module (2) are arranged to be relatively close to each other to form a sintering cavity (4) between the first template (11) and the second module (2), and the first heat insulation plate (12) is arranged between the piston plate (13) and the first template (11). A plurality of pressing rods (15) are movably arranged on the first template (11), and one or more pistons (16) are arranged in the piston plate (13). The piston (16) is arranged to be movable under the action of fluid and drives the pressing rod (15) to move through a heat insulation transmission member (17) or a plurality of heat insulation transmission members (17) in sequence, so that the pressing rod (15) applies pressure to the product (9) in the sintering cavity (4). The first template (11) or / and the second module (2) is provided with a heating assembly (5) for heating the product (9) in the sintering cavity (4). The transmission member (17) between the piston (16) and the pressing rod (15) driven by the piston (16) has one, the contact area between the piston (16) and the transmission member (17) is contact area A, the contact area between the transmission member (17) and the pressing rod (15) is contact area B, and at least one of the contact area A and the contact area B is smaller than the maximum cross-sectional area of the transmission member (17). Or the transmission member (17) between the piston (16) and the pressing rod (15) driven by the piston (16) has a plurality of, the contact area between the piston (16) and the transmission member (17) is contact area A, the contact area between the transmission member (17) and the pressing rod (15) is contact area B, and the contact area between the adjacent two transmission members (17) is contact area C, and at least one of the contact area A, the contact area B and the contact area C is smaller than the maximum cross-sectional area of the transmission member (17). The transmission member (17) has a heat insulation section (171) at one end in the moving direction of the piston (16) or has a heat insulation section (171) at both ends, the cross-sectional area of one end of the heat insulation section (171) is larger than that of the other end, and the end with the larger cross-sectional area of the heat insulation section (171) is fixedly connected with the transmission member (17) or is integrally formed with the transmission member (17).

2. The multi-press rod sintering apparatus according to claim 1, characterized by: A plurality of through holes (121) are formed in the first heat insulation plate (12), and the transmission member (17) is arranged in the through hole (121).

3. The multi-press rod sintering apparatus according to claim 1, characterized by: The heat insulation section (171) is conical, hemispherical or spherical.

4. The multi-press-rod sintering apparatus according to claim 2, characterized by: A bushing (18) is arranged between the through hole (121) of the first heat insulation plate (12) and the transmission member (17), the transmission member (17) is slidably arranged in the corresponding bushing (18), and the sliding direction of the transmission member (17) is parallel to the moving direction of the piston (16).

5. The multi-press rod sintering apparatus according to claim 2, characterized by: The transmission member (17) in contact with the pressing rod (15) is not in contact with the first template (11).

6. The multi-press ram sintering apparatus of claim 1, wherein: The pressing rod (15) is slidably installed on the first mold plate (11) along the moving direction of the piston (16), and the pressing rod (15) is fixedly connected with the first mold plate (11) in the circumferential direction.

7. The multi-press rod sintering apparatus according to claim 6, characterized by: A plurality of grooves (111) are arranged at the end face of the first mold plate (11) close to the first heat insulation plate (12), and a plurality of pressing rod holes (112) matched with the pressing rod (15) are arranged at the groove bottom of each groove (111). The pressing rod (15) corresponds to the pressing rod hole (112), and the pressing rod (15) is slidably installed in the corresponding pressing rod hole (112). The end of the pressing rod (15) close to the groove (111) has a head (151) for contacting the force transmission member (17), and the outer peripheral wall of the head (151) has a limiting surface (151a). The head (151) is located in the groove (111), and the limiting surface (151a) is in contact with the groove wall of the groove (111) to prevent the pressing rod (15) from rotating. The end of the head (151) close to the second mold plate (2) has a stepped surface (151b) for preventing the head (151) from entering the pressing rod hole (112).

8. The multi-press rod sintering apparatus according to claim 7, characterized by: The force transmission member (17) in contact with the pressing rod (15) has a gap between the groove wall of the groove (111) when the force transmission member (17) extends into the groove (111) to form an insulation area (111a).

9. The multi-press rod sintering apparatus according to claim 1, characterized by: The side of the piston (16) away from the first heat insulation plate (12) has a high-pressure chamber (19), a plurality of piston holes (131) are arranged on the piston plate (13), and the piston (16) corresponds to the piston hole (131). The piston (16) is slidably installed in the corresponding piston hole (131), and the high-pressure chamber (19) is in communication with the medium flow port (191). The hole of the piston hole (131) away from the first heat insulation plate (12) side is in communication with the high-pressure chamber (19).

10. The multi-press rod sintering apparatus according to claim 9, characterized by: The side of the piston plate (13) away from the first heat insulation plate (12) is sealingly fixed with a cover plate (14), and the high-pressure chamber (19) is formed between the piston plate (13), the piston (16) and the cover plate (14). The hole of the piston hole (131) away from the first heat insulation plate (12) side extends into the high-pressure chamber (19).

11. The multi-press rod sintering apparatus according to claim 9, characterized by: The gas supply device (6) includes a control gas path (61), a pressure regulating valve (62), a gas booster (63) and a working gas path (64). The pressure regulating valve (62) is connected in series on the control gas path (61), the inlet of the control gas path (61) is used for connecting a control gas source, and the outlet of the control gas path (61) is in communication with the gas booster (63). The gas booster (63) is connected in series on the working gas path (64), the inlet of the working gas path (64) is used for connecting a working gas source, and the outlet of the working gas path (64) is in communication with the medium flow port (191) of the high-pressure chamber (19). The control gas path (61) is used for providing power for the gas booster (63), so that the gas flowing into the gas booster (63) in the working gas path (64) is pressurized.

12. A sintering method based on the multi-press bar sintering apparatus according to any one of claims 1 to 11, characterized by: The method comprises the following steps: S1, the product (9) to be sintered is placed on the second module (2), the heating assembly (5) is heated, the film rolling mechanism (3) is placed with the film material (31) between the pressure rod (15) and the product (9); S2, the second module (2) is moved towards the first module (1); S3, after the product (9) contacts the film material (31), it continues to move towards the first module (1), and after the pressure rod (15) contacts the film material (31), it moves upwards by a certain distance to form a sintering cavity (4); S4, the first module (1) and the second module (2) are locked; S5, high-pressure gas is introduced, the piston (16) applies force to the second module (2) direction, through the force transmission member (17), the pressure rod (15) and the film material (31), the product (9) is pressurized; S6, heating, at the same time, the sintering cavity (4) is introduced into the sintering-promoting gas; S7, then the sintering cavity (4) is evacuated to remove the volatile gas during sintering, and then nitrogen is backfilled into the sintering cavity (4) to separate the film material (31) from the second module (2); S8, the piston (16) is decompressed, the second module (2) is moved away from the first module (1), the sintered product (9) is transferred to the cooling area with the second module (2) for cooling, and a sintering cycle is completed.

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