Pin fin bottom plate auxiliary heating tool and semiconductor device

Abstract

The utility model relates to the technical field of tool devices, and discloses a pin fin bottom plate auxiliary heating tool and a semiconductor device, and the pin fin bottom plate auxiliary heating tool comprises a heating tool housing which is partially recessed to form an accommodation groove; the filling particles are made of heat conduction materials, and the containing grooves are filled with the filling particles; the surface of the side, provided with the containing groove, of the heating tool shell is suitable for abutting against the surface, provided with the heat dissipation pin fins, of the pin fin bottom plate. The heat dissipation pin fins are suitable for extending into the containing grooves and make contact with the filling particles. According to the auxiliary heating tool for the pin fin bottom plate, after the heat dissipation pin fins extend into the containing grooves and make contact with the filling particles, the areas between the heat dissipation pin fins can be filled with the fine filling particles through the mobility of the filling particles, the filling particles can make contact with the heat dissipation pin fins in a self-adaptive mode, and therefore the heat dissipation effect is improved. And the condition of poor contact area caused by different lengths of the heat dissipation pin fins is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of tooling devices, in particular to a pin-fin bottom plate auxiliary heating tooling and a semiconductor device. Background Art

[0002] In recent years, with the rapid development of high-power-density emerging industries such as electric vehicles, smart grids, and rail transit, single power devices have become increasingly inadequate for meeting high-power demands. Power modules, which house two or more devices, are a key approach to addressing high-current, high-power applications. Large, high-power power modules generate significant heat. If this heat cannot be dissipated promptly, it can significantly impact module performance and lifespan. A baseplate with pinfins connects to the underlying water cooling plate, effectively improving module heat dissipation efficiency. Each ceramic substrate with chips is reflow-soldered to the upper surface of the pinfin baseplate, forming the basic architecture of the power module. Heat generated by the chips during operation is also quickly dissipated through the pinfin baseplate, ensuring efficient and stable chip operation.

[0003] Combine Figure 1 、 Figure 2 As shown, during reflow soldering, one method is to conduct heat to the pin-fin base plate 3 through the heating furnace plate 4, so that the solder located on the upper surface of the pin-fin base plate 3 melts, and then the pin-fin base plate 3 and the ceramic substrate waiting for the soldering unit 1 are connected together.

[0004] The contact area between the heat dissipating pin fins 32 on the lower surface of the pin-fin base plate 3 and the heating furnace plate 4 is much smaller than that of a conventional flat base plate, and it is difficult to achieve complete coplanarity of the heat dissipating pin fins 32, which further reduces the heat transfer area between the pin-fin base plate 3 and the heating furnace plate 4. This results in slower heat conduction of the pin-fin base plate 3, difficulty in debugging the process curve, and low production efficiency. In addition, during the reflow soldering stage, the coplanarity of the lower surface of the heat dissipating pin fins 32 in contact with the heating furnace plate 4 at different positions of the pin-fin base plate 3 is different, and the heat transfer efficiency will also be different, which will affect the reflow temperature stability and result in poor stability of the final product welding quality. For example, if the peak temperature is too low, the solder will not melt fully, and bubbles will not be easily discharged, forming voids in the solder layer; if the peak temperature is too high, the solder will be over-melted, intermetallic compounds will grow rapidly, the final thickness will be too large, and the solder layer will be prone to cracking. In the related art, the welding stability is improved by adding tooling and fixtures. Combined with Figure 3 、 Figure 4 As shown, it is the auxiliary heating fixture 5 before improvement, and the auxiliary heating fixture 5 before improvement is dug according to the pin fin distribution to form the heat dissipation pin fin coordination hole 51. Figure 5 、 Figure 6As shown, after the heat dissipation pin fin 32 is inserted into the heat dissipation pin fin matching hole 51, the heat dissipation pin fin 32 can be in contact with the heat dissipation pin fin matching hole 51 to avoid poor welding stability caused by different coplanarity of the heat dissipation pin fin 32.

[0005] However, the pre-improved auxiliary heating fixture 5 still suffers from a small heat transfer area. Furthermore, due to the limited machining precision of the pin-fin baseplate 3 and the heat dissipation pin-fin matching holes 51, the fit between the heat dissipation pin-fin matching holes 51 and the heat dissipation pin-fins 32 varies, resulting in varying heat transfer in different areas. Furthermore, the difficulty in machining the heat dissipation pin-fin matching holes 51 leads to low production efficiency. Different specifications of matching fixtures are required for different pin-fin baseplate 3 models, resulting in poor robustness. Utility Model Content

[0006] In view of this, the utility model provides a pin-fin base plate auxiliary heating tool and a semiconductor device to solve the problems of low heat transfer efficiency and uneven heat transfer of the pin-fin base plate.

[0007] In a first aspect, the present invention provides a pin-fin bottom plate auxiliary heating tool, comprising:

[0008] The heating tool shell is partially recessed to form a receiving groove;

[0009] Filling particles are made of heat-conducting material and are filled in the receiving groove;

[0010] The surface of the heating tool shell with the receiving groove is suitable for abutting against the surface of the pin-fin bottom plate with the heat dissipation pin fins; the heat dissipation pin fins are suitable for extending into the receiving groove and contacting the filling particles.

[0011] Beneficial Effects: The pin-fin base plate auxiliary heating fixture provided by the embodiment of the present invention forms a receiving groove in the heating fixture housing and fills the receiving groove with fine filling particles. Thus, after the heat dissipating pin fins are inserted into the receiving groove and contacted with the filling particles, the filling particles can utilize their own mobility to fill the area between the heat dissipating pin fins with the fine filling particles. The filling particles can adaptively contact the heat dissipating pin fins, avoiding the poor contact area caused by the uneven length of the heat dissipating pin fins. This greatly increases the heat transfer area of ​​the pin-fin base plate and significantly improves the welding stability.

[0012] The pin-fin base plate auxiliary heating tooling provided in the embodiment of the present invention does not need to open heat dissipation pin-fin coordination holes like the auxiliary heating tooling before the improvement. It only needs to fill small filling particles in the receiving groove. The adaptive mobility of the filling particles is utilized to avoid complicated processing processes, so that the molding efficiency of the pin-fin base plate auxiliary heating tooling is significantly improved, the tooling is simple to manufacture, and has good robustness.

[0013] The pin-fin baseplate auxiliary heating fixture provided in this embodiment allows for near-complete contact between the filler particles within the fixture and the lower surface of the pin-fin baseplate, increasing the heat transfer area, significantly improving the heating and cooling rates, and enhancing welding efficiency. This eliminates variations in heat transfer area due to errors such as pin-fin coplanarity and baseplate warpage, ensuring consistent temperature changes across the pin-fin baseplate, ensuring welding stability, and effectively improving welding efficiency.

[0014] The embodiment of the present invention provides an auxiliary heating tool for pin-fin base plates. One tool can be used with pin-fin base plates of various sizes. There is no need to equip each specification and model of pin-fin base plates with a separate heating tool. It has strong versatility and reduces batch production costs.

[0015] In an optional embodiment, the diameter of the filling particles is R, and satisfies: R<1 / 2L, where L is the minimum distance between adjacent heat dissipation pin fins.

[0016] Beneficial effect: It is helpful for filling particles to be fully filled into the spaces between the heat dissipation pin fins.

[0017] In an optional embodiment, the material of the filling particles includes copper or graphite.

[0018] Beneficial effect: The material of the filling particles is selected from high temperature resistant, high thermal conductivity and easy to process materials, thereby ensuring heat transfer efficiency.

[0019] In an optional embodiment, the pin-fin bottom plate auxiliary heating tool further includes:

[0020] The heating furnace plate is in contact with the surface of the heating tool shell on the side away from the receiving groove; the heat of the heating furnace plate is transferred to the pin-fin bottom plate through the heating tool shell and the filling particles.

[0021] In an optional embodiment, the diameter R of the filling particles further satisfies: R≥1 / 5L.

[0022] Beneficial effect: The particle size of the filling particles cannot be too small to prevent the particles from being carried away by the air flow in the furnace cavity and contaminating the cavity.

[0023] In an optional embodiment, when the pin-fin base plate is in an installed state, a projection of the pin-fin base plate toward the heating tool housing covers the receiving groove.

[0024] Beneficial effect: by making the projection of the pin-fin bottom plate toward the heating tool shell cover the receiving groove, the pin-fin bottom plate can cover the receiving groove after being closed, protecting the filling particles in the receiving groove and preventing them from being carried away by the airflow.

[0025] In an optional embodiment, the filling amount of filling particles in the receiving groove meets the following conditions: when the heat dissipating pin fins extend into the receiving groove and the pin fin base plate is in contact with the heating tool shell, the filling particles and the pin fin base plate forming the surface of the heat dissipating pin fins are in full contact.

[0026] Beneficial effect: By ensuring that the pin-fin base plate is in full contact with the surface of the pin-fin base plate forming the heat dissipating pin fins when the pin-fin base plate is in contact with the heating tool shell, the filling particles can be evenly spread out, the contact area is increased, the heat conduction area of ​​the pin-fin base plate is guaranteed, and the welding stability is higher.

[0027] In a second aspect, the present invention further provides a semiconductor device, comprising:

[0028] A pin-fin base plate, with a plurality of heat dissipating pin fins formed on one side surface of the pin-fin base plate;

[0029] The sub-unit to be soldered is connected to the surface of the pin-fin base plate on the side facing away from the heat dissipation pin fins;

[0030] The pin-fin base plate is heated by the pin-fin base plate auxiliary heating tool as described above so as to be welded with the sub-unit to be welded.

[0031] Beneficial Effects: In the semiconductor device provided by the embodiments of the present invention, the pin-fin baseplate is heated by the aforementioned pin-fin baseplate auxiliary heating fixture for welding to the subunit to be welded. This ensures a sufficient heat transfer area and prevents variations in heat transfer area due to errors such as pin-fin coplanarity and pin-fin baseplate warpage. The pin-fin baseplate temperature changes are essentially consistent, ensuring welding stability and effectively improving welding efficiency.

[0032] In an optional embodiment, a solder layer is further filled between the pin-fin base plate and the sub-unit to be soldered; after the pin-fin base plate auxiliary heating tool heats the pin-fin base plate, it is suitable for melting the solder layer.

[0033] In an optional embodiment, when the pin-fin base plate auxiliary heating tool is in use, the pin-fin base plate, the heating tool shell and the heating furnace plate are sequentially fitted and arranged.

[0034] Because the semiconductor device includes the pin-fin base plate auxiliary heating tool, it has the same effect as the pin-fin base plate auxiliary heating tool, and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0036] Figure 1 It is a schematic diagram of the sub-unit to be welded, the pin-fin base plate and the heating furnace plate of the present invention;

[0037] Figure 2 for Figure 1 Schematic diagram of the AA section;

[0038] Figure 3 This is a schematic diagram of the auxiliary heating tooling before improvement;

[0039] Figure 4 for Figure 3 Schematic diagram of the BB section;

[0040] Figure 5 This is a schematic diagram of the auxiliary heating tooling in use before improvement;

[0041] Figure 6 for Figure 5 Schematic diagram of CC section;

[0042] Figure 7 This is a schematic diagram of the auxiliary heating fixture for the pin-fin bottom plate of the present invention;

[0043] Figure 8 for Figure 7 Schematic diagram of DD section;

[0044] Figure 9 This is a schematic diagram of the use state of the pin-fin bottom plate auxiliary heating tool of the utility model;

[0045] Figure 10 for Figure 9 Schematic diagram of the EE cross section.

[0046] Description of reference numerals:

[0047] 1. Sub-unit to be soldered; 2. Solder layer; 3. Pin-fin base plate; 31. Board body; 32. Heat dissipation pin-fins; 33. Gap area; 4. Heating furnace plate; 5. Auxiliary heating tooling before improvement; 51. Heat dissipation pin-fin coordination holes; 6. Filling particles; 7. Heating tooling shell; 71. Receiving groove. DETAILED DESCRIPTION

[0048] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0049] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0050] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on specific circumstances.

[0051] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0052] Combine Figure 1 、 Figure 2 As shown, the pin-fin base plate 3 includes a plate body 31, one side of which is formed with a plurality of heat dissipating pin fins 32. The other side of the plate body 31 is suitable for soldering to the sub-unit 1 to be soldered. Due to reasons such as machining accuracy, it is difficult to achieve complete coplanarity of the heat dissipating pin fins 32, resulting in some heat dissipating pin fins 32 being longer and others being shorter. During reflow soldering, heat is transferred to the plate body 31 through contact between the heating furnace plate 4 and the heat dissipating pin fins 32. However, since some of the heat dissipating pin fins 32 are shorter, a gap area 33 is formed between the heating furnace plate 4 and the heat dissipating pin fins 32, resulting in uneven heat conduction from the pin-fin base plate 3.

[0053] Combine Figure 3 、 Figure 4As shown, the auxiliary heating tool 5 before improvement is dug according to the pin-fin distribution to form the heat dissipation pin-fin coordination hole 51. Figure 5 、 Figure 6 As shown, after the heat sink pin fin 32 is inserted into the heat sink pin fin matching hole 51, due to the poor coplanarity of the heat sink pin fin 32, a part of the heat sink pin fin 32 is short and cannot fit well with the heat sink pin fin matching hole 51. In addition, due to the limited processing accuracy of the pin fin base plate 3 and the heat sink pin fin matching hole 51, there are differences in the degree of fit between the heat sink pin fin matching hole 51 and the heat sink pin fin 32, and the heat transfer in different areas will also be different.

[0054] The pin-fin base plate auxiliary heating tooling provided in the embodiment of the present invention can overcome the defect of different lengths of the heat dissipation pin fins 32, thereby greatly increasing the heat conduction area of ​​the heat dissipation pin fins 32, making the heating more uniform, and significantly improving the welding stability.

[0055] The following combination Figures 1 to 10 , describing the embodiments of the present utility model.

[0056] According to an embodiment of the present invention, on the one hand, a pin-fin bottom plate auxiliary heating tool is provided, comprising:

[0057] The heating tool housing 7 is partially recessed to form a receiving groove 71;

[0058] Filling particles 6 are made of a heat-conducting material and are filled in the receiving groove 71;

[0059] The surface of the heating tool housing 7 on one side of which the receiving groove 71 is formed is suitable for abutting against the surface of the pin-fin base plate 3 formed with the heat dissipating pin fins 32; the heat dissipating pin fins 32 are suitable for extending into the receiving groove 71 and contacting the filling particles 6.

[0060] The pin-fin base plate auxiliary heating fixture provided by the embodiment of the present invention forms a receiving groove 71 in the heating fixture housing 7 and fills the receiving groove 71 with fine filling particles 6. Therefore, after the heat dissipating pin fins 32 are inserted into the receiving groove 71 and contacted with the filling particles 6, the mobility of the filling particles 6 can be utilized to fill the area between the heat dissipating pin fins 32 with the fine filling particles 6. The filling particles 6 can adaptively contact the heat dissipating pin fins 32, avoiding the poor contact area caused by the uneven length of the heat dissipating pin fins 32. This greatly increases the heat transfer area of ​​the pin-fin base plate 3 and significantly improves the welding stability.

[0061] The pin-fin base plate auxiliary heating tooling provided in the embodiment of the present invention does not need to open the heat dissipation pin-fin coordination holes 51 like the auxiliary heating tooling 5 before the improvement. It only needs to fill the receiving groove 71 with fine filling particles 6. The adaptive mobility of the filling particles 6 is utilized to avoid complicated processing processes, so that the molding efficiency of the pin-fin base plate auxiliary heating tooling is significantly improved, the tooling is simple to manufacture, and has good robustness.

[0062] During specific use, the pin-fin base plate 3 is placed on the upper surface of the heating tool shell 7, and the upper surface of the pin-fin base plate 3 is pressed manually or by equipment to immerse the heat dissipating pin fins 32 in the filling particles 6. The operation is simple and the adaptability is good.

[0063] Optionally, in order to improve the heat transfer efficiency, after the pin-fin base plate 3 is placed in place, the filling particles 6 are in full contact with the surface of the pin-fin base plate 3 where the heat dissipating pin fins 32 are formed, thereby ensuring the heat transfer effect.

[0064] Compared with the auxiliary heating tooling 5 before the improvement, the pin-fin base plate auxiliary heating tooling provided by the embodiment of the utility model has a pin-fin base plate 3 whose warping has little effect on heat conduction, and when the coplanarity of the heat dissipating pin fins 32 is not good, it can also be well filled with filling particles 6, thereby improving the fault tolerance and reducing the precision requirements.

[0065] The pin-fin baseplate auxiliary heating fixture provided in the present invention allows for near-complete contact between the filler particles 6 within the fixture and the lower surface of the pin-fin baseplate 3. This increases the heat transfer area, significantly improves the heating and cooling rates, and enhances welding efficiency. This eliminates variations in heat transfer area due to errors such as the coplanarity of the heat-dissipating pin fins 32 and the warpage of the pin-fin baseplate 3. The temperature of the pin-fin baseplate 3 changes consistently, ensuring welding stability and effectively improving welding efficiency.

[0066] In addition, the embodiment of the present invention provides a pin-fin base plate auxiliary heating tooling, and one tooling can be used with pin-fin base plates 3 of various sizes. There is no need to equip each specification and model of pin-fin base plates 3 with a separate heating tooling. It has strong versatility and reduces batch production costs.

[0067] In some embodiments, the filling particles 6 are made of copper or graphite.

[0068] The filling particles 6 are made of materials that are resistant to high temperatures, highly thermally conductive, and easy to process, thereby ensuring heat transfer efficiency.

[0069] In some embodiments, combined Figure 9 、 Figure 10 As shown, the pin-fin bottom plate auxiliary heating tooling also includes:

[0070] The heating furnace plate 4 abuts against the surface of the heating tool shell 7 on the side facing away from the receiving groove 71 ; the heat of the heating furnace plate 4 is transferred to the pin-fin bottom plate 3 via the heating tool shell 7 and the filling particles 6 .

[0071] In some embodiments, the diameter of the filling particles 6 is R, and satisfies: R<1 / 2L, where L is the minimum distance between adjacent heat dissipation pin fins 32 .

[0072] In some embodiments, the diameter R of the filling particles 6 also satisfies: R≥1 / 5L.

[0073] The filling particles 6 are small particles to ensure that they can be filled between the heat dissipation pin fins 32. The diameter R of the filled filling particles 6 needs to be smaller than the minimum spacing between the heat dissipation pin fins 32, and can further be lower than half of the minimum spacing between adjacent heat dissipation pin fins 32, which is conducive to the filling particles 6 being fully filled between the heat dissipation pin fins 32.

[0074] Additionally, the particle size of the filler particles 6 should not be too small to prevent them from being carried away by the airflow within the furnace cavity and contaminating the cavity. A particle size that is too large should not be too large, as this will increase the gaps between the particles, reduce the contact area between the filler particles 6 and the heat dissipation pin fins 32, and reduce the heat transfer efficiency.

[0075] In some embodiments, combined Figure 9 As shown, in the installed state of the pin-fin base plate 3 , the projection of the pin-fin base plate 3 toward the heating tool housing 7 covers the receiving groove 71 .

[0076] By making the projection of the pin-fin bottom plate 3 toward the heating tool shell 7 cover the receiving groove 71, the pin-fin bottom plate 3 can cover the receiving groove 71 after being covered, protecting the filling particles 6 in the receiving groove 71 and preventing them from being carried away by the airflow.

[0077] In some embodiments, combined Figure 10 As shown, the filling amount of the filling particles 6 in the receiving groove 71 meets the following conditions: when the heat dissipating pin fins 32 extend into the receiving groove 71 and the pin fin base plate 3 is in contact with the heating tool shell 7, the filling particles 6 and the pin fin base plate 3 forming the surface of the heat dissipating pin fins 32 are in a complete contact state.

[0078] It should be noted that full contact refers to the fact that the filler particles 6 within the receiving groove 71 are in full contact with the surface of the pin-fin base plate 3, where the heat dissipating pin fins 32 are formed, to ensure effective heat transfer. Since the filler particles 6 are often round or irregular in shape, gaps exist between the filler particles 6, preventing them from achieving 100% contact with the pin-fin base plate 3. Full contact refers to the fact that the filler particles 6, as a whole, have a sufficient overlap area with the pin-fin base plate 3.

[0079] By ensuring that the pin-fin base plate 3 is in full contact with the surface of the pin-fin base plate 3 forming the heat dissipating pin fins 32 when the pin-fin base plate 3 is in contact with the heating tool shell 7, the filling particles 6 can be evenly spread out, the contact area is increased, the heat conduction area of ​​the pin-fin base plate 3 is guaranteed, and the welding stability is higher.

[0080] According to an embodiment of the present invention, on the other hand, a semiconductor device is provided, including:

[0081] A pin-fin base plate 3, with a plurality of heat dissipating pin fins 32 formed on one side surface of the pin-fin base plate 3;

[0082] The sub-unit 1 to be soldered is connected to the surface of the pin-fin base plate 3 facing away from the heat dissipation pin fins 32;

[0083] The pin-fin base plate 3 is heated by the pin-fin base plate auxiliary heating tool as described above so as to be welded with the sub-unit 1 to be welded.

[0084] The sub-unit to be soldered 1 includes a ceramic substrate, a chip and bonding wires thereon.

[0085] In the semiconductor device provided by the embodiments of the present invention, the pin-fin base plate 3 is heated by the aforementioned pin-fin base plate auxiliary heating fixture for welding to the sub-unit 1 to be welded. This ensures a sufficient heat transfer area and prevents variations in heat transfer area due to errors such as the coplanarity of the heat dissipating pin fins 32 and the warpage of the pin-fin base plate 3. The temperature changes of the pin-fin base plate 3 are essentially consistent, ensuring welding stability and effectively improving welding efficiency.

[0086] In some embodiments, a solder layer 2 is further filled between the pin-fin base plate 3 and the sub-unit 1 to be soldered; after the pin-fin base plate auxiliary heating tool heats the pin-fin base plate 3, it is suitable for melting the solder layer 2.

[0087] The solder layer 2 may be solder paste, etc., so that the pin-fin base plate 3 can be connected to the sub-unit 1 to be soldered after melting.

[0088] In some embodiments, combined Figure 10 As shown, when the pin-fin base plate auxiliary heating tool is in use, the pin-fin base plate 3, the heating tool shell 7 and the heating furnace plate 4 are sequentially arranged to ensure the contact area, improve the heat transfer efficiency and ensure the heat transfer uniformity.

[0089] To facilitate understanding of the specific use of the pin-fin base plate auxiliary heating tool provided in the embodiment of the present invention, the following describes the welding process of semiconductor devices:

[0090] In the first step, the filling particles 6 are filled into the receiving groove 71 of the heating tool shell 7 so that the filling particles 6 are evenly spread.

[0091] In the second step, the pin-fin base plate 3 is placed on the upper surface of the heating tool shell 7 so that the heat dissipating pin fins 32 extend into the receiving groove 71. The upper surface of the pin-fin base plate 3 is pressed manually or by equipment so that the heat dissipating pin fins 32 are immersed in the filling particles 6. It is preferred to ensure that the filling particles 6 are in complete contact with the lower surface of the pin-fin base plate 3.

[0092] In the third step, if the solder layer 2 is solder paste, print the solder paste on the top surface of the pin-fin baseplate 3, specifically at the locations corresponding to the subunits 1 to be soldered. By covering the top surface of the pin-fin baseplate 3 with a stencil, use a scraper to scrape the solder paste through the openings in the stencil until the solder paste adheres to the locations corresponding to the subunits 1 to be soldered, completing the solder paste printing. If the solder layer 2 is a solder sheet, directly pick up the solder sheet and place it on the locations corresponding to the subunits 1 to be soldered.

[0093] The fourth step is to pick up the sub-unit 1 to be soldered and place it on the surface where the solder paste was printed or the solder piece was mounted in the previous step.

[0094] The fifth step is to transfer the above assembled parts (including the heating tool shell 7, filling particles 6, pin-fin base plate 3, solder paste / solder sheet, and sub-unit 1 to be soldered) to the heating furnace plate 4, and check the sealing performance of the combination between the pin-fin base plate 3 and the heating tool shell 7 again to prevent internal particles from being brought out during the reflow soldering process and contaminating the furnace cavity.

[0095] The sixth step is to perform reflow soldering.

[0096] Obviously, the above embodiments are merely examples for the purpose of clarity of explanation and are not intended to limit the implementation methods. Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the present invention.

Claims

1. A pin-fin bottom plate auxiliary heating tool, characterized in that: include: The heating tool housing (7) is partially recessed to form a receiving groove (71); Filling particles (6) are made of a heat-conducting material, and the filling particles (6) are filled in the containing groove (71); The surface of the heating tool housing (7) on one side of which the receiving groove (71) is formed is suitable for abutting against the surface of the pin-fin base plate (3) on which the heat dissipating pin fins (32) are formed; the heat dissipating pin fins (32) are suitable for extending into the receiving groove (71) and contacting the filling particles (6).

2. The pin-fin bottom plate auxiliary heating tool according to claim 1, characterized in that: The diameter of the filling particles (6) is R, and satisfies: R<1 / 2L, wherein L is the minimum distance between adjacent heat dissipation pin fins (32).

3. The pin-fin bottom plate auxiliary heating tool according to claim 1, characterized in that: The material of the filling particles (6) includes copper or graphite.

4. The pin-fin bottom plate auxiliary heating tool according to claim 1, characterized in that: The pin-fin bottom plate auxiliary heating tool also includes: The heating furnace plate (4) abuts against the surface of the heating tool shell (7) on the side facing away from the receiving groove (71); the heat of the heating furnace plate (4) is transferred to the pin-fin bottom plate (3) via the heating tool shell (7) and the filling particles (6).

5. The pin-fin bottom plate auxiliary heating tool according to claim 2, characterized in that: The diameter R of the filling particles (6) also satisfies: R≥1 / 5L.

6. The pin-fin bottom plate auxiliary heating tool according to any one of claims 1 to 5, characterized in that: When the pin-fin base plate (3) is in an installed state, the projection of the pin-fin base plate (3) toward the heating tool housing (7) covers the accommodating groove (71).

7. The pin-fin bottom plate auxiliary heating tool according to any one of claims 1 to 5, characterized in that: The filling amount of the filling particles (6) in the receiving groove (71) satisfies the following condition: when the heat dissipating pin fins (32) extend into the receiving groove (71) and the pin fin base plate (3) is in contact with the heating tool shell (7), the filling particles (6) and the surface of the pin fin base plate (3) on which the heat dissipating pin fins (32) are formed are in a complete contact state.

8. A semiconductor device, characterized in that: include: A pin-fin base plate (3), wherein a plurality of heat dissipating pin fins (32) are formed on one side surface of the pin-fin base plate (3); The sub-unit to be welded (1) is connected to a surface of the pin-fin base plate (3) on a side facing away from the heat dissipating pin-fins (32); The pin-fin base plate (3) is heated by the pin-fin base plate auxiliary heating tool as described in any one of claims 1 to 7 above, so as to be welded with the sub-unit (1) to be welded.

9. The semiconductor device according to claim 8, wherein A solder layer (2) is also filled between the pin-fin base plate (3) and the sub-unit to be soldered (1); after the pin-fin base plate auxiliary heating tool heats the pin-fin base plate (3), it is suitable for melting the solder layer (2).

10. The semiconductor device according to claim 8, wherein When the pin-fin base plate auxiliary heating fixture is in use, the pin-fin base plate (3), the heating fixture shell (7) and the heating furnace plate (4) are sequentially fitted and arranged.

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