Power module and its manufacturing method

Abstract

This application provides a power module and a method for manufacturing the power module. The power module includes a first circuit board, a second circuit board, multiple connecting posts, and adhesive. Multiple electronic components are fixed to the first and second circuit boards via solder, and each connecting post is connected to the first and second circuit boards via adhesive. After two reflow soldering cycles, the connecting posts are reliably fixed to the first and second circuit boards by the cured adhesive, effectively preventing misalignment or separation of the first and second circuit boards during subsequent reflow soldering or other processing, such as back-mounting of the power module, thereby enhancing the toughness of the power module. Furthermore, the manufacturing method of the power module of this application reduces the number of reflow soldering cycles, thereby reducing the thermal shock of reflow soldering to the first circuit board, the second circuit board, and the electronic components, and lowering production costs.

Description

Technical Field

[0001] This case pertains to the technical field of power modules, and more particularly to a two-layer power module and a method for manufacturing the power module. Background Technology

[0002] With the increasing demands for power supply performance in recent years, the industry's requirements for power modules have become increasingly stringent. A common structure for power modules is the dual-layer power module, which comprises two distinct printed circuit board (PCBA) assemblies, such as a control board and a power board. In manufacturing this type of power module, the control board undergoes front-side solder paste printing, and electronic components are mounted onto it, followed by reflow soldering to form a separate control board unit. Simultaneously, the power board undergoes front-side solder paste printing, and electronic components are mounted onto it, followed by reflow soldering to complete the front-side soldering. Next, solder paste is printed on the back side of the power board, and electronic components and magnetic cores are mounted onto it. Finally, the control board is soldered onto the back side of the power board and reflow soldered to complete the back-side soldering, thus forming the dual-layer power module.

[0003] However, existing dual-layer power modules have shortcomings in application. In practical scenarios, it is often necessary to combine the dual-layer power module with another system board. Specifically, the dual-layer power module is soldered to the front of the system board via the back of the control board, and a reflow soldering is performed to fix the dual-layer power module to the system board. Then, the entire structure is flipped to mount other electronic components on the back of the system board, and a second reflow soldering is performed (i.e., reflow soldering with the back of the power module). During the second reflow soldering process, the high temperature causes the solder between the power board and the control board of the dual-layer power module to remelt. Due to the interaction between the solder tension and the module's own weight, the power board and control board separate, while the control board remains soldered to the system board. Ultimately, the product consisting of the dual-layer power module and the system board cannot function properly, resulting in significant losses.

[0004] Therefore, how to develop a power module and a power module manufacturing method to solve the problems faced by the existing technology is an urgent issue to be addressed in this field. Summary of the Invention

[0005] This application provides a power module and a method for manufacturing the power module. The power module includes a first circuit board, a second circuit board, multiple connecting posts, and adhesive. Multiple electronic components are fixed to the first and second circuit boards via solder, and each connecting post is connected to the first and second circuit boards via adhesive. After two reflow soldering cycles, the connecting posts are reliably fixed to the first and second circuit boards by the cured adhesive, effectively preventing misalignment or separation of the first and second circuit boards during subsequent reflow soldering or other processing, such as when the power module is mounted on the back in a reflow oven. This enhances the toughness and reliability of the power module. Furthermore, the manufacturing method of the power module of this application reduces the number of reflow soldering cycles, thereby reducing the thermal shock of reflow soldering to the first circuit board, the second circuit board, and the electronic components, and lowering production costs.

[0006] To achieve the above objectives, this application provides a power module. The power module includes a first circuit board, a second circuit board, a plurality of connecting posts, and at least one adhesive. The first circuit board has a first side and a second side opposite to each other, and includes at least one first electronic component. The first electronic component is fixed to the first side of the first circuit board by solder. The second circuit board has a third side and a fourth side opposite to each other, and includes at least one second electronic component. The second electronic component is fixed to the third side of the second circuit board by solder, wherein the second side of the first circuit board and the third side of the second circuit board are opposite to each other. Each connecting post has a first end and a second end opposite to each other, the first end being adjacent to the first circuit board and the second end being adjacent to the second circuit board. Each connecting post is connected to the first circuit board and the second circuit board by adhesive.

[0007] To achieve the above objectives, this application provides a method for manufacturing a power module. The method includes the steps of: (S1) providing a first circuit board, a second circuit board, a first electronic component, a second electronic component, a plurality of connecting posts, a first adhesive, and a second adhesive, wherein the first circuit board has a first and a second surface opposite to each other, the second circuit board has a third and a fourth surface opposite to each other, and each connecting post has a first end and a second end opposite to each other; (S2) applying the first adhesive to at least one first dispensing area on the second surface of the first circuit board, and applying the second adhesive to at least one second dispensing area on the third surface of the second circuit board, wherein the first electronic component is soldered to the first surface of the first circuit board, and the second electronic component is soldered to the third surface of the second circuit board; (S3) dispensing each connecting post to the second circuit board... (S4) On the corresponding second dispensing area of ​​the board, the second end of each connecting post is in contact with the second fixing adhesive; (S5) Perform a first reflow soldering on the second circuit board and the plurality of connecting posts, wherein after the second fixing adhesive cures, the plurality of connecting posts are fixed on the third surface of the second circuit board, and after the solder cures, at least one second electronic component is fixed on the third surface of the second circuit board; (S6) Stack the second circuit board onto the first circuit board, wherein the first end of each connecting post corresponds to the corresponding first dispensing area of ​​the first circuit board and is in contact with the first fixing adhesive; (S7) Perform a second reflow soldering, wherein after the first fixing adhesive cures, the first circuit board and the second circuit board are fixed via the plurality of connecting posts, and after the solder cures, the first electronic component is fixed on the first surface of the first circuit board. Attached Figure Description

[0008] Figure 1A This is a schematic diagram of the power module according to the first embodiment of this application.

[0009] Figure 1B for Figure 1A The diagram shows an exploded view of the power module.

[0010] Figure 1C for Figure 1A An exploded view of the power module shown from another perspective.

[0011] Figure 2A for Figure 1A The diagram shows the structural schematic of the connection post of the power module.

[0012] Figure 2B for Figure 2A The diagram shows a structural schematic of the connecting column from another perspective.

[0013] Figure 3A This is a schematic diagram of the power module structure according to the second embodiment of this application.

[0014] Figure 3B for Figure 3AThe diagram shows an exploded view of the power module.

[0015] Figure 3C for Figure 3A The diagram shows an exploded view of the power module from another perspective.

[0016] Figure 4A for Figure 3A The diagram shows the structural structure of the power module connector.

[0017] Figure 4B for Figure 4A An exploded view of the connectors of the power module shown.

[0018] Figure 5A This is a schematic diagram of the power module according to the third embodiment of this application.

[0019] Figure 5B for Figure 5A The diagram shows an exploded view of the power module.

[0020] Figure 5C for Figure 5A An exploded view of the power module shown from another perspective.

[0021] Figure 6A This is a schematic diagram of the power module according to the fourth embodiment of this application.

[0022] Figure 6B for Figure 6A The diagram shows an exploded view of the power module.

[0023] Figure 6C for Figure 6A An exploded view of the power module shown from another perspective.

[0024] Figure 7 This is a flowchart illustrating the steps of a method for manufacturing a power module according to the first embodiment of this application.

[0025] Figure 8 for Figure 7 The flowchart shows the sub-steps of step (S5) of the manufacturing method of the power module shown.

[0026] Figure 9 for Figure 7 A flowchart illustrating another embodiment of the manufacturing method of the power module shown.

[0027] Figure 10 for Figure 7 A flowchart illustrating another embodiment of the manufacturing method of the power module shown.

[0028] Figure 11 for Figure 7A flowchart illustrating another embodiment of the manufacturing method of the power module shown.

[0029] Figure 12 This is a flowchart illustrating the steps of a method for manufacturing a power module according to a second embodiment of this application.

[0030] The attached figures are labeled as follows: 100, 100a, 100b, 100c: Power modules 1: First circuit board 11: First Page 12: Second page 13: Grooving 131: First slot 132: Second slot 133: Third slot 134: Fourth slot 14: Magnetic core 141: First magnetic core 142: Second magnetic core 143: Third magnetic core 144: Fourth magnetic core 15: Notch 150: Zhou Yuan 2: Second circuit board 21: Third page 22: Fourth page 25: Notch 250: Zhou Yuan 3, 3a: Connecting column 31, 31a: First end 301: Part One 310: First Groove 32, 32a: Second end 302: Part Two 320: Second groove 33, 33a: Sidewall 34: Trench 35: Through hole 36: Protrusion 4: Fixative 41: First fixing adhesive 410: First dot glue area 42: Second fixing adhesive 420: Second glue area 43: Third fixing adhesive 3: Connecting column 4: Fixative 5: Conductive block 51: First end 52: Second end 53: Mounting holes 54: Conductive post 6: Solder 7: Connectors 81: First Electronic Component 82: Second Electronic Component 83: Third Electronic Component S1, S2, S3, S4, S5, S6, S7: Steps S51, S52: Sub-steps Detailed Implementation

[0031] Some typical embodiments of the features and advantages of this application will be described in detail in the following description. It should be understood that this application can have various variations in different ways, all of which do not depart from the scope of this application, and the descriptions and drawings therein are for illustrative purposes only and not for limiting this application. For example, if the following description of this application states that a first feature is disposed on or above a second feature, it means that it includes embodiments in which the first feature and the second feature are in direct contact, and also includes embodiments in which additional features may be disposed between the first feature and the second feature, so that the first feature and the second feature may not be in direct contact. In addition, different embodiments in this application may use repeated reference numerals and / or markings. These repetitions are for simplification and clarity and are not intended to limit the relationship between the various embodiments and / or the described appearance structures. Furthermore, in order to facilitate the description of the relationship between one component or feature and another (plural) component or feature in the drawings, spatial terms such as "upper," "lower," "top," "bottom," and similar terms may be used. In addition to the orientations shown in the accompanying drawings, spatially relevant terms are used to cover different orientations of the device in use or operation. The device may also be otherwise positioned (e.g., rotated 90 degrees or located in other orientations), and the descriptions of the spatially relevant terms used will be interpreted accordingly. Furthermore, when a component is referred to as "connected to" or "coupled to" another component, it may be directly connected to or coupled to the other component, or there may be intervening components. Although the numerical ranges and parameters of the broad scope of this application are approximate, the values ​​are stated as precisely as possible in specific examples. Additionally, it is understood that although terms such as "first," "second," "third," and "fourth" may be used in the claims to describe different components, these components should not be limited by these terms, and the components described accordingly in the embodiments are represented by different component symbols. These terms are used to distinguish different components. For example, a first component may be referred to as a second component, and similarly, a second component may be referred to as a first component without departing from the scope of the embodiments. The term "and / or" as thus used includes any or all combinations of one or more of the related listed items. Some embodiments of this application will now be described in detail with reference to the accompanying drawings. Where there is no conflict, the following embodiments and features can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0032] Figure 1A This is a schematic diagram of the power module according to the first embodiment of this application. Figure 1B for Figure 1A The exploded view of the power module shown is as follows. Figure 1C for Figure 1A The diagram shown is an exploded view of the power module from another perspective. Figure 2A for Figure 1AThe diagram shows the structure of the connection posts of the power module. Figure 2B for Figure 2A The diagram shows a structural schematic of the connecting column from another perspective.

[0033] The power module 100 includes a first circuit board 1, a second circuit board 2, a plurality of connecting posts 3, and at least one adhesive 4. The first circuit board 1 has a first surface 11 and a second surface 12 opposite to each other, and includes at least one first electronic component 81. The first electronic component 81 is fixed to the first surface 11 of the first circuit board 1 via solder 6. The second circuit board 2 has a third surface 21 and a fourth surface 22 opposite to each other, and includes at least one second electronic component 82. The second electronic component 82 is fixed to the third surface 21 of the second circuit board 2 via solder 6, wherein the second surface 12 of the first circuit board 1 and the third surface 21 of the second circuit board 2 are opposite to each other. Each connecting post 3 has a first end 31 and a second end 32 opposite to each other, the first end 31 of the connecting post 3 being adjacent to the first circuit board 1, and the second end 32 of the connecting post 3 being adjacent to the second circuit board 2. Each connecting post 3 is connected to the first circuit board 1 and the second circuit board 2 via adhesive 4. The adhesive 4, after curing once by reflow soldering, will not melt again due to subsequent reflow soldering, wherein the adhesive 4 can be selected from thermosetting materials such as glue or epoxy resin. Furthermore, the position of the connecting posts 3 between the first circuit board 1 and the second circuit board 2 can be adjusted according to actual needs. For example, the two connecting posts 3 can be positioned near the center of the first circuit board 1 and the second circuit board 2. In some embodiments, the first circuit board 1 is a power board, and the second circuit board 2 is a control board, wherein the fourth surface 22 of the second circuit board 2 is used to connect to an external system board (not shown) to provide power to the components on the external system board. In some embodiments, such as Figure 1B and 1C As shown, the first circuit board 1 further includes at least one third electronic component 83, which is fixed to the second surface 12 of the first circuit board 1 via solder 6. It should be noted that the type and quantity of the first electronic component 81, the second electronic component 82, and the third electronic component 83 are not limited in this application, and various electronic components can be selected according to requirements. In some embodiments, the curing temperature of the fixing adhesive 4 is higher than the melting point of the solder 6, or in other embodiments, the curing temperature of the fixing adhesive 4 is lower than the melting point of the solder 6.

[0034] After two reflow soldering cycles, the adhesive 4 at both ends of the connecting post 3 of the power module 100 is cured. Thus, the first end 31 and the second end 32 of the connecting post 3 are fixedly connected to the first circuit board 1 and the second circuit board 2 via the cured adhesive 4, thereby enhancing the reliability of the connection between the first circuit board 1 and the second circuit board 2. Furthermore, once cured, the adhesive 4 will not remelt due to reflow soldering. In subsequent processing steps, such as during the production of the power module 100 mounted on the system board, when the system board and the power module 100 are flipped (i.e., the back of the power module 100 is reflow mounted), the connecting post 3 and the cured adhesive 4 effectively ensure a reliable connection between the first circuit board 1 and the second circuit board 2, making it difficult for the first circuit board 1 and the second circuit board 2 to detach or misalign, greatly improving the toughness and reliability of the power module 100.

[0035] like Figure 2A and 2B As shown, each connecting post 3 has four sidewalls 33 between its first end 31 and second end 32, and the four sidewalls 33 surround the connecting post 3. Furthermore, the first end 31 of each connecting post 3 is a plane, and the second end 32 has at least one groove 34. The plane shape of the first end 31 allows the machining machinery to better position the connecting post 3. The groove 34 is located on the second end 32 of the connecting post 3 and extends through both opposite sides of the second end 32. The groove 34 is a space for accommodating the fixing adhesive 4. For example, as... Figure 2A and 2B As shown, the connecting post 3 has two grooves 34. It should be noted that the number and orientation of the grooves 34 can be adjusted according to actual needs. The grooves 34 effectively prevent the adhesive from being excessively squeezed out, avoiding interference with the soldering of surrounding components, and also enhance the bonding strength. It should be noted that the planar structure of the first end 31 of the connecting post 3 needs to maintain a certain gap, for example, 0.1mm to 0.5mm, between it and the adhesive application area on the surface of the connected circuit board to avoid excessive adhesive squeezing that could affect the soldering of surrounding components.

[0036] Furthermore, in this embodiment, such as Figure 1B and 1CAs shown, at least one setter adhesive 4 comprises a first setter adhesive 41 and a second setter adhesive 42. The first end 31 of each connecting post 3 is connected to the second surface 12 of the first circuit board 1 via the first setter adhesive 41, and the second end 32 of each connecting post 3 is connected to the third surface 21 of the second circuit board 2 via the second setter adhesive 42. Therefore, after the power module 100 undergoes two reflow soldering cycles, the connecting posts 3 are fixedly connected to the second surface 12 of the first circuit board 1 via the cured first setter adhesive 41, and to the third surface 21 of the second circuit board 2 via the cured second setter adhesive 42, thus effectively supporting and fixing the power module 100. Furthermore, a portion of the second setter adhesive 42 is accommodated and filled within at least one groove 34, allowing the tension of the second setter adhesive 42 to more effectively fix the connecting post 3 to the second circuit board 2. In some embodiments, the amount of each setter adhesive 4 may be between 0.6 mg and 0.8 mg. It should be noted that during the first reflow soldering process, after the second fixing adhesive 42 cures, the second end 32 of the connecting post 3 can be fixedly connected to the third surface 21 of the second circuit board 2; during the second reflow soldering process, after the first fixing adhesive 41 cures, the first end 31 of the connecting post 3 can be fixedly connected to the second surface 12 of the first circuit board 1.

[0037] Furthermore, in some embodiments, the second surface 12 of the first circuit board 1 has at least one first adhesive dispensing area 410, and the third surface 21 of the second circuit board 2 has at least one second adhesive dispensing area 420. A first adhesive 41 is disposed on the first adhesive dispensing area 410, and a second adhesive 42 is disposed on the second adhesive dispensing area 420. It should be noted that the number and position of the first adhesive dispensing area 410 and the second adhesive dispensing area 420 can be adjusted according to actual needs.

[0038] Furthermore, in this embodiment, such as Figure 1B and 1C As shown, the power module 100 also includes a plurality of conductive blocks 5. Each conductive block 5 has a first end 51 and a second end 52 on opposite sides. The first end 51 of the conductive block 5 is connected to the second surface 12 of the first circuit board 1, and the second end 52 of the conductive block 5 is connected to the third surface 21 of the second circuit board 2. The conductive blocks 5 are used to transmit signals or energy between the first circuit board 1 and the second circuit board 2. It should be noted that the size, shape, placement position and number of the conductive blocks 5 between the first circuit board 1 and the second circuit board 2 can be adjusted according to actual needs. For example, the conductive blocks 5 may have mounting holes 53 (which will be described later).

[0039] Furthermore, in this embodiment, the first circuit board 1 includes at least one slot 13 and at least one magnetic core 14. The slot 13 extends through the first surface 11 and the second surface 12 of the first circuit board 1, and each magnetic core 14 is disposed within a corresponding slot 13. For example, as Figure 1A ,1B As shown in 1C, at least one slot 13 includes a first slot 131, a second slot 132, a third slot 133, and a fourth slot 134. The first slot 131 and the second slot 132 are located near the center of the first circuit board 1 and are arranged parallel to each other. The third slot 133 and the fourth slot 134 are adjacent to the side of the first circuit board 1 and are arranged parallel to each other. At least one magnetic core 14 includes a first magnetic core 141, a second magnetic core 142, a third magnetic core 143, and a fourth magnetic core 144. The first magnetic core 141 and the second magnetic core 142 are located on the first surface 11 and the second surface 12 of the first circuit board 1, respectively, and are also located in the first slot 131 and the second slot 132, forming a magnetic assembly. The third magnetic core 143 and the fourth magnetic core 144 are located on the first surface 11 and the second surface 12 of the first circuit board 1, respectively, and are also located in the third slot 133 and the fourth slot 134, forming a magnetic assembly. In this embodiment, the first magnetic core 141, the second magnetic core 142, the third magnetic core 143, and the fourth magnetic core 144 are U-shaped magnetic cores. It should be noted that the shape, location, and number of slots 13 and magnetic cores 14 can be adjusted according to actual needs, and this application does not limit them.

[0040] Figure 3A This is a schematic diagram of the power module structure according to the second embodiment of this application. Figure 3B for Figure 3A The exploded view of the power module shown is as follows. Figure 3C for Figure 3A The diagram shown is an exploded view of the power module from another perspective. Figure 4A for Figure 3A The diagram shows the structural structure of the power module connectors. Figure 4B for Figure 4A The diagram shows an exploded view of the connector of the power module. In this embodiment, the structure and function of the power module 100a are similar to those of the power module 100 in the first embodiment, wherein the same component labels represent the same structural components and functions, which will not be described again here. Unlike the power module 100 in the first embodiment, the power module 100a in this embodiment has a first portion 301 and a second portion 302 adjacent to the first portion 301 on the first end 31a and the second end 32a of the connecting post 3a. The first portion 301 of the first end 31a has a first groove 310, and the first portion 301 of the second end 32a has a second groove 320, and the first groove 310 and the second groove 320 are opposite to each other. Each connecting post 3a also includes at least one through hole 35 and at least one protrusion 36. The at least one through hole 35 passes through the second portion 302 on the first end 31a and the second portion 302 on the second end 32a, wherein the at least one protrusion 36 is provided on at least one side wall 33a of the four side walls 33a.

[0041] Furthermore, in this embodiment, such as Figure 4A and 4B As shown, the conductive block 5 includes at least one mounting hole 53, which extends through two opposite sides between the first end 51 and the second end 52 of the conductive block 5, and the mounting hole 53 mates with the corresponding protrusion 36 of the connecting post 3a. Specifically, the protrusion 36 of the connecting post 3a is inserted into the mounting hole 53 of the conductive block 5, such that one conductive block 5 of the plurality of conductive blocks 5 mates with one connecting post 3a of the plurality of connecting posts 3a. The connecting post 3a and the conductive block 5 mate with each other to form a connector 7.

[0042] Furthermore, in this embodiment, the power module 100a also includes at least one conductive post 54. The conductive post 54 is disposed in a corresponding through-hole 35 of the connecting post 3a, and both ends of the conductive post 54 protrude from the second portion 302 of the first end 31a and the second portion 302 of the second end 32a of the connecting post 3a, respectively. The portions of the conductive post 54 protruding from the connecting post 3a are respectively connected to the first circuit board 1 and the second circuit board 2 for transmitting signals or energy. In some embodiments, the number of through-holes 35 and the number of conductive posts 54 are equal, and the number of through-holes 35 and conductive posts 54 can be adjusted according to actual needs.

[0043] Furthermore, in this embodiment, as Figure 3B and 3C As shown, at least one adhesive 4 includes a first adhesive 41 and a second adhesive 42. The first end 31a of each connecting post 3a is connected to the second surface 12 of the first circuit board 1 via the first adhesive 41, and the second end 32a of each connecting post 3a is connected to the third surface 21 of the second circuit board 2 via the second adhesive 42. Each conductive block 5 is connected to the second surface 12 of the first circuit board 1 and the third surface 21 of the second circuit board 2 via solder 6. A portion of the first adhesive 41 is accommodated in the first groove 310, and a portion of the second adhesive 42 is accommodated in the second groove 320. The groove design effectively prevents the adhesive from being over-pressed and overflowing, avoiding affecting the soldering of surrounding components. It also enhances the bonding strength, allowing the tension of the first adhesive 41 to more effectively fix the connecting post 3a to the first circuit board 1, and the tension of the second adhesive 42 to more effectively fix the connecting post 3a to the second circuit board 2, thus enhancing the tension of the power module structure and the stability of the connection. In some embodiments, such as Figure 4A and 4B As shown, the first groove 310 and the second groove 320 are trapezoidal grooves, and the inner corners of the trapezoidal grooves have rounded designs. The bottom surface of the trapezoidal grooves is parallel to the first end 31a and / or the second end 32a of the connecting column 3a.

[0044] Therefore, the connector 7 in this embodiment can be effectively fixed between the first circuit board 1 and the second circuit board 2, while also supporting the first circuit board 1 and the second circuit board 2, and transmitting signals or energy via the conductive block 5 and the conductive post 54. Furthermore, since the connecting post 3a and the conductive block 5 are integrated into the connector 7, the space utilization on the first circuit board 1 and the second circuit board 2 can be improved.

[0045] Figure 5A This is a schematic diagram of the power module according to the third embodiment of this application. Figure 5B for Figure 5A The exploded view of the power module shown is as follows. Figure 5C for Figure 5A The diagram shows an exploded view of the power module from another perspective. In this embodiment, the structure and function of the power module 100b are similar to those of the power module 100 in the first embodiment, wherein the same component labels represent the same structural components and functions, which will not be described again here. Unlike the power module 100 in the first embodiment, the first circuit board 1 of the power module 100b in this embodiment includes at least one recess 15. The recess 15 extends from the periphery 150 of the first circuit board 1 toward the center, that is, the periphery 150 of the first circuit board 1 is recessed toward the center of the first circuit board 1 to form the recess 15. The number of recesses 15 can be adjusted according to actual needs.

[0046] In this embodiment, at least one fixing adhesive 4 includes a first fixing adhesive 41 and a second fixing adhesive 42. The first end 31 of each connecting post 3 is connected to the recess 15 of the first circuit board 1 via the first fixing adhesive 41, and the second end 32 of each connecting post 3 is connected to the second circuit board 2 via the second fixing adhesive 42. In other words, in this embodiment, the surface of the first end 31 of the connecting post 3 is approximately perpendicular to the inner surface of the recess 15 of the first circuit board 1, and the first fixing adhesive 41 is simultaneously connected and fixed to both the surface of the first end 31 of the connecting post 3 and the inner surface of the recess 15 of the first circuit board 1, forming a semi-circular shape. Furthermore, a portion of the surface of the first end 31 of the connecting post 3 contacts the second surface 12 of the first circuit board 1, and the connecting post 3 supports the first circuit board 1. The recess 15 facilitates the addition of fixing adhesive to the first circuit board 1 and provides space for the curing of the fixing adhesive, effectively preventing the adhesive from being excessively squeezed and overflowing, avoiding interference with the soldering of surrounding components, and enhancing the bonding strength. Furthermore, during the connection of the connecting post 3 and the conductive block 5 with the first circuit board 1 and the second circuit board 2, the second end 32 of the connecting post 3 and the second end 52 of the conductive block 5 can be solidified and welded to the third surface 21 of the second circuit board 2 firstly, the first end 51 of the conductive block 5 can be welded to the second surface 12 of the first circuit board 1, and finally the first end 31 of the connecting post 3 and the second surface 12 of the first circuit board 1 can be solidified and welded. This can avoid the problem of poor soldering or false soldering caused by the fixing adhesive curing first.

[0047] Furthermore, in this embodiment, such as Figure 5A and 5B As shown, the connecting post 3 can be selected from the connecting post 3 in the power module 100, but it can also be adjusted according to actual needs. Through this embodiment, the setting of fixing adhesive 4 on the side of the connecting post 3 and the first circuit board 1 is beneficial for troubleshooting, and the precision requirements of the reflow soldering process for producing this power module 100b are reduced.

[0048] Figure 6A This is a schematic diagram of the power module according to the fourth embodiment of this application. Figure 6B for Figure 6A The diagram shows an exploded view of the power module. Figure 6C for Figure 6AThe diagram shows an exploded view of the power module from another perspective. In this embodiment, the structure and function of the power module 100c are similar to those of the power module 100 in the first embodiment, wherein the same component labels represent the same structural components and functions, which will not be described again here. Unlike the power module 100 in the first embodiment, the power module 100c in this embodiment also includes a third adhesive 43 in at least one fixing adhesive 4. In addition, the second circuit board 2 includes at least one notch 25. The notch 25 extends from the periphery 250 of the second circuit board 2 toward the center, that is, the periphery 250 of the second circuit board 2 is recessed toward the center of the second circuit board 2 to form the notch 25. The number of notches 25 can be adjusted according to actual needs.

[0049] Furthermore, in this embodiment, the distance between the first circuit board 1 and the second circuit board 2 is small, and the height of the connecting post 3 is small, for example, less than or equal to 1.5 mm, but this application does not limit it.

[0050] In this embodiment, the third adhesive 43 is disposed on the sidewall 33 of at least one connecting post 3 and simultaneously connected to the first circuit board 1 and the second circuit board 2. Specifically, the third adhesive 43 is simultaneously connected to and fixed to the inner surface of the recess 25 of the second circuit board 2, the sidewall 33 of the connecting post 3, and the second surface 12 of the first circuit board 1. That is, the sidewall 33 of the connecting post 3 forms an adhesive-supporting post. Furthermore, in some embodiments, the connecting post 3 may be made of metal. In some embodiments, such as Figure 6A and 6B As shown, the first circuit board 1 includes a third electronic component 83, which is disposed within the first circuit board 1.

[0051] In addition, this application provides a method for manufacturing a power module for manufacturing the power modules 100 and 100a described above. However, the method for manufacturing the power modules 100, 100a, 100b and 100c described above is not limited to the following method.

[0052] Figure 7 This is a flowchart illustrating the manufacturing method of the power module according to this application. Figure 8 for Figure 7 The flowchart shows the sub-steps of step (S5) in the manufacturing method of the power module. Figure 9 for Figure 7 The flowchart illustrates another embodiment of the manufacturing method of the power module. Figure 10 for Figure 7 The flowchart illustrates another embodiment of the manufacturing method of the power module. Figure 11 for Figure 7 A flowchart illustrating another embodiment of the manufacturing method of the power module is shown. Please refer to [link / reference]. Figure 7 , Figure 8 , Figure 9 , Figure 10 and Figure 11 The power module manufacturing method of this embodiment includes the following steps, as shown in Figures 1A, 1B, and 1C.

[0053] First, in step S1, a first circuit board 1, a second circuit board 2, at least one first electronic component 81, at least one second electronic component 82, a plurality of connecting posts 3, a first adhesive 41, and a second adhesive 42 are provided. The first circuit board 1 has a first surface 11 and a second surface 12 that are opposite to each other, the second circuit board 2 has a third surface 21 and a fourth surface 22 that are opposite to each other, and each connecting post 3 has an opposite first end 31 and a second end 32.

[0054] Furthermore, in some embodiments, such as Figure 9 As shown, in step S1, a plurality of conductive blocks 5 are also provided, each conductive block 5 having a first end 51 and a second end 52 opposite to each other. In some embodiments, such as Figure 11 As shown, in step S1, at least one magnetic core 14 is also provided.

[0055] Furthermore, in some embodiments, such as Figure 10 As shown, at least one third electronic component 83 is also provided.

[0056] Next, in step S2, a first adhesive 41 is applied to at least one first adhesive application area 410 on the second surface 12 of the first circuit board 1, and a second adhesive 42 is applied to at least one second adhesive application area 420 on the third surface 21 of the second circuit board 2. A first electronic component 81 is disposed on the first surface 11 of the first circuit board 1 via solder 6, and a second electronic component 82 is disposed on the third surface 21 of the second circuit board 2 via solder 6.

[0057] Furthermore, in some embodiments, such as Figure 9 As shown, in step S2, the second end 52 of each conductive block 5 is disposed on the third surface 21 of the second circuit board 2 via solder 6, and additional solder 6 is disposed on the second surface 12 of the first circuit board 1.

[0058] Furthermore, in some embodiments, such as Figure 11 As shown, in step S2, a portion of the magnetic core 14 is disposed within the corresponding slot 13. For example, the second magnetic core 142 is disposed simultaneously from the second surface 12 of the first circuit board 1 in the first slot 131 and the second slot 132, and the fourth magnetic core 144 is disposed simultaneously from the second surface 12 of the first circuit board 1 in the third slot 133 and the fourth slot 134. The disposal method can be a snap-fit ​​method, which is not limited in this application.

[0059] Furthermore, in some embodiments, such as Figure 10As shown, in step S2, the third electronic component 83 is also disposed on the second side 12 of the first circuit board 1 via solder 6.

[0060] Next, in step S3, each connecting post 3 is positioned on the corresponding second adhesive application area 420 of the second circuit board 2. The second end 32 of each connecting post 3 is in contact with the second adhesive 42.

[0061] Next, in step S4, a first reflow soldering is performed on the second circuit board 2 and the plurality of connecting posts 3. During the first reflow soldering, after the second adhesive 42 cures, the plurality of connecting posts 3 are fixed to the third surface 21 of the second circuit board 2, and after the solder 6 cures, at least one second electronic component 82 is fixed to the third surface 21 of the second circuit board 2. Additionally, in some embodiments, after the solder 6 cures, a plurality of conductive blocks 5 are also fixed to the third surface 21 of the second circuit board 2.

[0062] Next, in step S5, the second circuit board 2 is stacked onto the first circuit board 1. The first end 31 of each connecting post 3 corresponds to the corresponding first dispensing area 410 of the first circuit board 1 and is in contact with the first fixing adhesive 41. In addition, in some embodiments, the first end 51 of each conductive block 5 is simultaneously aligned with additional solder 6 on the second surface 12 of the first circuit board 1.

[0063] In some embodiments, such as Figure 8 As shown, step S5 includes sub-steps S51 and S52.

[0064] First, in sub-step S51, the second circuit board 2 is flipped so that the third side 21 of the second circuit board 2 faces the second side 12 of the first circuit board 1.

[0065] Next, in sub-step S52, the first end 31 of each connecting post 3 is aligned with the corresponding first dispensing area 410 of the first circuit board 1 and in contact with the first fixing adhesive 41, so as to stack the second circuit board 2 onto the first circuit board 1.

[0066] Next, in step S6, a second reflow soldering is performed. During the second reflow soldering, after the first adhesive 41 cures, the first circuit board 1 and the second circuit board 2 are fixed together via multiple connecting posts 3. Furthermore, after the solder 6 cures, the first electronic component 81 is also fixed to the first surface 11 of the first circuit board 1. Additionally, in some embodiments, after the solder 6 cures, multiple conductive blocks 5 are also fixed between the third surface 21 of the second circuit board 2 and the second surface 12 of the first circuit board 1.

[0067] Furthermore, in some embodiments, such as Figure 10 As shown, in step S6, after the solder 6 is cured, the third electronic component 83 is also fixed to the second side 12 of the first circuit board 1.

[0068] Next, in some embodiments, such as Figure 11 As shown, in step S7, another portion of the magnetic core 14 is disposed within the corresponding slot 13 to form at least one magnetic component. For example, the first magnetic core 141 is disposed simultaneously on the first surface 11 of the first circuit board 1 in the first slot 131 and the second slot 132, so that the first magnetic core 141 and the second magnetic core 142 together form a magnetic component; and the third magnetic core 143 is disposed simultaneously on the first surface 11 of the first circuit board 1 in the third slot 133 and the fourth slot 134, so that the third magnetic core 143 and the fourth magnetic core 144 together form a magnetic component. The magnetic core 14 can be disposed in a snap-fit ​​manner, which is not limited in this application.

[0069] Figure 12 This is a flowchart illustrating the manufacturing method of a power module according to the second embodiment of this application, and is used in conjunction with... Figure 3A , Figure 3B , Figure 3C , Figure 4A and Figure 4B The manufacturing method of the power module in this embodiment is based on the production of the aforementioned power module 100a. Therefore, the manufacturing method of this embodiment may optionally include the manufacturing method and embodiment of the aforementioned power module 100, and the same parts will not be described again here. In this embodiment, the connecting post 3a and the conductive block 5 are assembled together to form the connector 7.

[0070] In step S2, additional solder 6 will be applied to the second side 12 of the first circuit board 1.

[0071] In step S3, the conductive block 5 of the connector 7 is also set on the third surface 21 of the second circuit board 2 via solder 6, and the connecting post 3a of the connector 7 is set on the third surface 21 of the second circuit board 2 via the second fixing adhesive 42.

[0072] In step S4, during the first reflow soldering process, after the second adhesive 42 cures, the connecting post 3a of the connector 7 is fixed to the third surface 21 of the second circuit board 2 via the second adhesive 42. Furthermore, after the solder 6 cures, the conductive block 5 of the connector 7 is also fixed to the third surface 21 of the second circuit board 2. In addition, the conductive post 54 of the connector 7 is also simultaneously fixed to the third surface 21 of the second circuit board 2.

[0073] In step S5, the first end 51 of the conductive block 5 of the connector 7 is aligned with the additional solder 6 on the second surface 12 of the first circuit board 1, and the first end 31a of the connecting post 3a of the connector 7 is aligned with the first adhesive area 410 of the first circuit board 1.

[0074] In step S6, after the solder 6 solidifies, the conductive block 5 of the connector 7 is fixed between the third surface 21 of the second circuit board 2 and the second surface 12 of the first circuit board 1. Furthermore, the conductive post 54 of the connector 7 is also simultaneously fixed to the second surface 12 of the first circuit board 1.

[0075] Therefore, through the above steps, the connector 7 can be effectively fixed between the first circuit board 1 and the second circuit board 2, which not only has the function of supporting the first circuit board 1 and the second circuit board 2, but also greatly enhances the reliability of the connection between the first circuit board 1 and the second circuit board 2, and can also transmit signals or energy through the conductive block 5 and the conductive post 54.

[0076] This application provides a power module and a method for manufacturing the power module. The power module includes a first circuit board, a second circuit board, multiple connecting posts, and adhesive. Multiple electronic components are fixed to the first and second circuit boards via solder, and each connecting post is connected to the first and second circuit boards via adhesive. After two reflow soldering cycles, the connecting posts are reliably fixed to the first and second circuit boards by the cured adhesive, effectively preventing misalignment or separation of the first and second circuit boards during subsequent reflow soldering or other processing, such as back-mounting of the power module, thereby enhancing the toughness of the power module. Furthermore, the manufacturing method of the power module of this application reduces the number of reflow soldering cycles, thereby reducing the thermal shock of reflow soldering to the first circuit board, the second circuit board, and the electronic components, and lowering production costs.

Claims

1. A power module, characterized in that, Include: A first circuit board has a first side and a second side opposite to each other, and includes at least one first electronic component, wherein the at least one first electronic component is fixed to the first side of the first circuit board via a solder. A second circuit board has a third side and a fourth side opposite to each other, and includes at least one second electronic component, the at least one second electronic component being fixed to the third side of the second circuit board via solder, wherein the second side of the first circuit board and the third side of the second circuit board are opposite to each other; Multiple connecting posts, each of the connecting posts having a first end and a second end opposite to each other, the first end being adjacent to the first circuit board and the second end being adjacent to the second circuit board; as well as At least one adhesive is used to fix each of the connecting posts to the first circuit board and the second circuit board via the at least one adhesive.

2. The power module as described in claim 1, characterized in that, Each of the connecting posts has four sidewalls between its first end and second end, and the four sidewalls surround the connecting post. The power module further includes a plurality of conductive blocks, each of the conductive blocks having a first end and a second end on opposite sides. The first end of the conductive block is adjacent to the first circuit board, and the second end of the conductive block is adjacent to the second circuit board.

3. The power module as described in claim 2, characterized in that, Each of the connecting posts has a first portion and a second portion adjacent to the first portion on its first end and a second portion on its second end, wherein the first portion of the first end has a first groove and the first portion of the second end has a second groove, and the first groove and the second groove are opposite to each other, wherein each of the connecting posts further includes at least one through hole and at least one protrusion, wherein the at least one through hole simultaneously passes through the second portion on the first end and the second portion on the second end, wherein the at least one protrusion is disposed on at least one side wall of the four side walls.

4. The power module as described in claim 3, characterized in that, One of the plurality of conductive blocks is coupled to one of the plurality of connecting posts, wherein the conductive block includes at least one mounting hole that extends through two opposite sides between the first end and the second end of the conductive block, and the at least one mounting hole is coupled to a corresponding protrusion of the connecting post.

5. The power module as described in claim 4, characterized in that, The at least one fixing adhesive includes a first fixing adhesive and a second fixing adhesive. The first end of each of the connecting posts is connected to the first circuit board via the first fixing adhesive, and the second end of each of the connecting posts is connected to the second circuit board via the second fixing adhesive. Each of the conductive blocks is connected to the first circuit board and / or the second circuit board via the solder. A portion of the first fixing adhesive is contained in the first groove, and a portion of the second fixing adhesive is contained in the second groove.

6. The power module as described in claim 4, characterized in that, At least one conductive post is disposed in the corresponding through hole of each of the connecting posts, the at least one conductive post protruding from the second portion of the first end and the second end of the connecting post, and connected to the first circuit board and the second circuit board.

7. The power module as described in claim 1 or 2, characterized in that, Each of the connecting posts has a first end that is a plane and a second end that has at least one groove, the at least one groove being located on the second end of the connecting post and extending through both opposite sides of the second end.

8. The power module as described in claim 7, characterized in that, The at least one fixing adhesive includes a first fixing adhesive and a second fixing adhesive. The first end of each of the connecting posts is connected to the first circuit board via the first fixing adhesive, and the second end of each of the connecting posts is connected to the second circuit board via the second fixing adhesive, wherein a portion of the second fixing adhesive is accommodated within the at least one groove.

9. The power module as described in claim 1 or 2, characterized in that, The first circuit board includes at least one notch extending from a periphery of the first circuit board toward the center. The at least one adhesive includes a first adhesive and a second adhesive. The first end of each connecting post is connected to the corresponding notch of the first circuit board via the first adhesive, and the second end of each connecting post is connected to the second circuit board via the second adhesive.

10. The power module as described in claim 1 or 2, characterized in that, The at least one fixing adhesive includes a third fixing adhesive, which is disposed on one side wall of at least one of the connecting posts and is simultaneously connected to the first circuit board and the second circuit board, wherein the side wall is located between the first end and the second end of the connecting post.

11. The power module as described in claim 1 or 2, characterized in that, The first circuit board includes at least one slot and at least one magnetic core, wherein each magnetic core is disposed in the corresponding slot to form a magnetic assembly.

12. The power module as described in claim 1, characterized in that, The first circuit board includes at least one third electronic component, wherein the at least one third electronic component is fixed to the second surface of the first circuit board via a solder, and / or the at least one third electronic component is disposed within the first circuit board.

13. A method for manufacturing a power module, characterized in that, Includes the following steps: (S1) A first circuit board, a second circuit board, at least one first electronic component, at least one second electronic component, a plurality of connecting posts, a first adhesive and a second adhesive are provided, wherein the first circuit board has a first side and a second side opposite to each other, the second circuit board has a third side and a fourth side opposite to each other, and each of the connecting posts has a first end and a second end opposite to each other. (S2) The first adhesive is applied to at least one first dispensing area on the second side of the first circuit board, and the second adhesive is applied to at least one second dispensing area on the third side of the second circuit board, wherein at least one first electronic component is disposed on the first side of the first circuit board via a solder, and at least one second electronic component is disposed on the third side of the second circuit board via the solder. (S3) Each of the connecting posts is disposed on the corresponding second dispensing area of ​​the second circuit board, wherein the second end of each of the connecting posts is in contact with the second fixing adhesive; (S4) A first reflow soldering is performed on the second circuit board and the plurality of connecting posts, wherein after the second adhesive cures, the plurality of connecting posts are fixed to the third surface of the second circuit board, and, After the solder has solidified, the at least one second electronic component is fixed to the third surface of the second circuit board; (S5) The second circuit board is stacked on the first circuit board, wherein the first end of each of the connecting posts corresponds to the corresponding first dispensing area of ​​the first circuit board and is in contact with the first fixing adhesive. (S6) Perform a second reflow soldering, wherein after the first adhesive has cured, the first circuit board and the second circuit board are fixed via a plurality of the connecting posts, and after the solder has cured, the at least one first electronic component is fixed to the first surface of the first circuit board.

14. The manufacturing method as described in claim 13, characterized in that, Step (S5) includes the following sub-steps: (S51) Flip the second circuit board so that the third surface of the second circuit board faces the second surface of the first circuit board; and (S52) Align the first end of each of the connecting posts with the corresponding first dispensing area of ​​the first circuit board and make contact with the first fixing adhesive to stack the second circuit board onto the first circuit board.

15. The manufacturing method as described in claim 13, characterized in that, In step (S1), a plurality of conductive blocks are also provided, each of the conductive blocks having a first end and a second end opposite to each other; In step (S2), the second end of each conductive block is also disposed on the third surface of the second circuit board via the solder, and additional solder is disposed on the second surface of the first circuit board; In step (S4), after the solder has solidified, the plurality of conductive blocks are fixed to the third surface of the second circuit board; In step (S5), the first end of each conductive block is also aligned with the additional solder on the second side of the first circuit board; as well as In step (S6), after the solder is cured, a plurality of conductive blocks are fixed between the third side of the second circuit board and the second side of the first circuit board.

16. The manufacturing method as described in claim 13, characterized in that, One of the plurality of connecting posts is assembled with a conductive block to form a connector, wherein In step (S2), additional solder is also applied to the second surface of the first circuit board; In step (S3), the conductive block of the connector is also disposed on the third side of the second circuit board via the solder, and the connecting post of the connector is disposed on the third side of the second circuit board via the second fixing adhesive; In step (S4), after the second adhesive cures, the connecting post of the connector is fixed to the third side of the second circuit board via the second adhesive, and after the solder cures, the conductive block of the connector is fixed to the third side of the second circuit board. In step (S5), the first end of the conductive block of the connector is aligned with the additional solder on the second side of the first circuit board, and the first end of the connecting post of the connector is aligned with the first dispensing area of ​​the first circuit board. In step (S6), after the solder is cured, the conductive block of the connector is fixed between the third side of the second circuit board and the second side of the first circuit board.

17. The manufacturing method as described in claim 13, characterized in that, The first circuit board includes at least one slot, and in step (S1), at least one magnetic core is also provided, wherein the at least one magnetic core includes a plurality of magnetic cores; In step (S2), portions of the magnetic cores of the plurality of magnetic cores are further disposed within the corresponding slots; and In one step (S7), another portion of the magnetic cores of the plurality of magnetic cores are disposed in the corresponding slots to form at least one magnetic assembly.

18. The manufacturing method as described in claim 13, characterized in that, In step (S1), at least one third electronic component is also provided; In step (S2), the at least one third electronic component is also disposed on the second side of the first circuit board via the solder; as well as In step (S6), the second reflow soldering is performed, and after the solder solidifies, the at least one third electronic component is fixed to the second surface of the first circuit board.

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