JP2014045152A - Component mounting board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a component mounting board having a high bonding strength between a wiring board and electronic components and bonding failure is hardly generated between the wiring board and the electronic components even when repair processing is made.SOLUTION: In a component mounting board 10, a wiring layer 12 is formed over the surface 11a of an insulation substrate 11 and the wiring layer 12 is coated by a resist 13. The resist 13 includes an opening 14 formed therein. In the opening 14, a terminal 21 of the electronic component 2 has a joint plane 12a electrically connected to the surface of the wiring layer 12 is exposed from the resist 13, and the entire of the opening 14 is covered by the electronic component 2. A first space 31 within the opening 14 closed by the wiring layer 12 and the electronic component 2 is filled with solder 41. The solder 41 electrically connects the terminal 21 and the joint plane 12a to each other. In a second space 32 formed by the upper face of the resist 13 and the side faces of the electronic component 2, a hardened material 42 of a thermosetting resin joins the resist 13 and the electronic component 2 to each other.

Description

  The present invention relates to a component mounting board, and more particularly, to a structure for joining a wiring board and an electronic component.

  Conventionally, low-melting-point solder has been used as a bonding material for electrically bonding electronic components to a wiring board. Conventionally, solder for bonding has been formed in a fillet shape in order to increase the bonding strength between the wiring board and the electronic component. The solder formed in a fillet shape is called a solder fillet. However, the solder fillet alone is not sufficient for improving the bonding strength. When the component mounting board receives an impact from the outside, the electric bonding between the wiring board and the electronic component may be broken.

  Therefore, in order to further improve the bonding strength, it has been proposed to use a solder paste containing a low melting point solder and a thermosetting resin as a bonding material (see, for example, Patent Document 1). When a solder fillet is formed during mounting using this solder paste, a cured resin film 104 is formed on the solder fillet 103 as shown in FIG. 9 (see, for example, Patent Document 2). Specifically, after applying a solder paste to the joint surface between the electronic component 102 and the wiring substrate 101, the solder paste is heated to melt the solder and soften the thermosetting resin. As a result, the solder and the thermosetting resin are separated, whereby the solder having a large specific gravity moves downward to form the solder fillet 103, and the thermosetting resin having a small specific gravity moves upward to move the resin cured film. 104 is formed. Therefore, the solder fillet 103 is reinforced by the resin cured film 104, and as a result, the bonding strength is improved.

  In the manufactured component mounting substrate, when a mounting defect (for example, bonding failure) of the electronic component or a defect of the electronic component itself is found, a repair process is performed on the component mounting substrate. Here, the repair process is a process of removing the mounted electronic component from the wiring board and then mounting a new electronic component on the wiring board again. The removal of the electronic component is performed using an apparatus such as a suction nozzle in a state where the solder fillet is melted and the resin cured film is softened while heating the joining portion (solder fillet and resin cured film).

JP 2011-56527 A JP 2006-287060 A

  However, when the electronic component 102 is removed from the wiring board 101 in the repair process for the conventional component mounting board shown in FIG. 9, the solder 105 and the thermosetting material are formed on the surface of the wiring board 101 as shown in FIG. The resin 106 remains in contact with each other. Alternatively, the solder 105 and the thermosetting resin 106 remain mixed on the surface of the wiring board 101. For this reason, when a new electronic component is remounted, a thermosetting resin is mixed in a newly formed solder fillet, and as a result, a bonding failure may occur between the wiring board 101 and the electronic component. was there.

  Accordingly, an object of the present invention is to provide a component mounting board that has a high bonding strength between a wiring board and an electronic component and that hardly causes defective bonding between the wiring board and the electronic component when a repair process is performed. is there.

  A component mounting board according to the present invention includes a wiring board and an electronic component mounted on the wiring board. The wiring substrate includes an insulating substrate, a wiring layer formed on the surface of the insulating substrate, and a resist that covers the wiring layer. An opening is formed in the resist, and the opening exposes a bonding surface, on the surface of the wiring layer, to which the terminal of the electronic component is electrically bonded from the resist, while the entire opening is covered with the electronic component. The first space in the opening closed by the wiring layer and the electronic component is filled with solder, and the terminal and the joint surface are electrically joined to each other by the solder. In the second space formed by the upper surface of the resist and the side surface of the electronic component, a cured product of the thermosetting resin joins the resist and the electronic component to each other.

  According to the component mounting board of the present invention, the bonding strength between the wiring board and the electronic component is high, and when a repair process is performed, a bonding failure is unlikely to occur between the wiring board and the electronic component.

It is sectional drawing which showed the component mounting board | substrate which concerns on 1st Embodiment of this invention. It is sectional drawing which showed the component mounting board | substrate which concerns on 2nd Embodiment of this invention. FIG. 3 is an enlarged view of a region III shown in FIG. 2. It is the block diagram which showed the manufacturing line which comprises the manufacturing system about the system which manufactures the component mounting board which concerns on this invention. It is sectional drawing which showed the specific structure of the manufacturing line. It is sectional drawing for demonstrating the position (mounting position) on the wiring board in which an electronic component is mounted by the mounting apparatus with which a manufacturing line is provided. It is sectional drawing for demonstrating the state of this solder paste when solder paste is heated with the heating apparatus with which a manufacturing line is provided. FIG. 2 is a cross-sectional view for explaining a state of a wiring board when an electronic component is removed in a repair process for the component mounting board shown in FIG. 1. It is sectional drawing which showed the conventional component mounting board | substrate. It is sectional drawing for demonstrating the state of a wiring board when an electronic component is removed in the repair process with respect to the conventional component mounting board | substrate.

  First, a component mounting board according to the present invention will be described.

  A component mounting board according to the present invention includes a wiring board and an electronic component mounted on the wiring board. The wiring substrate includes an insulating substrate, a wiring layer formed on the surface of the insulating substrate, and a resist that covers the wiring layer. An opening is formed in the resist, and the opening exposes a bonding surface, on the surface of the wiring layer, to which the terminal of the electronic component is electrically bonded from the resist, while the entire opening is covered with the electronic component. More specifically, the entire opening is covered with the terminals of the electronic component.

  The first space in the opening closed by the wiring layer and the electronic component is filled with solder, and the terminal and the joint surface are electrically joined to each other by the solder. On the other hand, no thermosetting resin is present in the first space. Or even if the thermosetting resin exists in the first space, the amount is about 5 vol%. In the second space formed by the upper surface of the resist and the side surface of the electronic component, a cured product of the thermosetting resin joins the resist and the electronic component to each other. On the other hand, no solder is present in the second space. Alternatively, even if solder is present in the second space, the amount is about 5 vol%.

  In the component mounting board, the first space and the second space are blocked by the electronic component. For this reason, the second space is formed at a position separated from the first space along the upper surface of the resist. Therefore, the cured product in the second space does not contact the solder in the first space.

  Therefore, in the repair process for the component mounting board, when the electronic component is removed from the wiring board, the solder and the thermosetting resin remain on the wiring board, but the solder is located in the opening, and the thermosetting resin is Therefore, it is positioned on the upper surface of the resist without contacting the solder. For this reason, even when a new electronic component is remounted, the thermosetting resin hardly mixes in the solder. Therefore, even when a repair process is performed on the component mounting board, poor bonding is unlikely to occur between the wiring board and the electronic component.

  In the component mounting board, the wiring board and the electronic component are joined to each other in the first space by solder. In addition to this, the wiring board and the electronic component are joined to each other by a cured product of a thermosetting resin in the second space. Therefore, in the component mounting board, the bonding strength between the wiring board and the electronic component is high.

  In the specific configuration of the component mounting board, further, in the third space formed by the upper surface of the resist and the lower surface of the electronic component, the cured product of the thermosetting resin joins the resist and the electronic component to each other. Yes. On the other hand, there is no solder in the third space. Alternatively, even if solder exists in the third space, the amount is about 5 vol%.

  Here, like the second space, the third space is blocked by the electronic component from the first space. For this reason, the third space is formed at a position separated from the first space along the upper surface of the resist. Therefore, the cured product in the third space does not come into contact with the solder in the first space. Therefore, even when a repair process is performed on a component mounting board having a specific configuration, a bonding failure is unlikely to occur between the wiring board and the electronic component.

  Further, in the component mounting board having the above specific configuration, the wiring board and the electronic component are joined together by the solder in the first space and the cured product in the second space. They are joined together by a cured product in the space. Therefore, in this component mounting board, the bonding strength between the wiring board and the electronic component is further increased.

  Embodiments of the present invention will be specifically described below with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a component mounting board according to a first embodiment of the present invention. As shown in FIG. 1, the component mounting board 10 includes a wiring board 1 and an electronic component 2 mounted on the wiring board 1. The wiring substrate 1 includes an insulating substrate 11, a wiring layer 12 (wiring pattern) formed on the surface 11 a of the insulating substrate 11, and a solder resist 13 that covers the wiring layer 12.

  The electronic component 2 has a component main body 20 composed of passive elements such as capacitor elements, and two electrode layers 21 formed at both ends of the component main body 20 (the right end portion and the left end portion in FIG. 1). doing. A part of each electrode layer 21 extends on the lower surface of the component body 20. Therefore, in the electronic component 2, two terminals exposed on the lower surface of the electronic component 2 are configured by the electrode layer 21.

  As shown in FIG. 1, two openings 14 corresponding to the electrode layers 21 are formed in the solder resist 13. The opening 14 exposes, from the solder resist 13, the bonding surface 12 a to which the electrode layer 21 is electrically bonded in the surface of the first wiring layer 12. On the other hand, each opening 14 is entirely covered with an electrode layer 21 corresponding to the opening 14. Thereby, the space in the opening 14 is a space (first space 31) closed by the wiring layer 12 and the electronic component 2.

  The first space 31 is filled with the solder 41, and the electrode layer 21 and the joint surface 12 a are electrically joined to each other by the solder 41. On the other hand, no thermosetting resin is present in the first space 31. Alternatively, even if the thermosetting resin is present in the first space 31, the amount is about 5 vol%. For the solder 41, for example, Sn-Bi-based or Sn-Bi-Ag-based low melting point solder is used.

  Further, as shown in FIG. 1, a cured product 42 of a thermosetting resin exists in the second space 32 formed by the upper surface of the solder resist 13 and the side surface of the electronic component 2. On the other hand, no solder is present in the second space 32. Alternatively, even if solder exists in the second space 32, the amount thereof is about 5 vol%. Specifically, the cured product 42 fills a corner formed by the solder resist 13 and the electronic component 2 in the second space 32 and spreads in a fillet shape around the corner. Thus, the cured product 42 joins the solder resist 13 and the electronic component 2 to each other in the second space 32. For example, an epoxy resin is used as the thermosetting resin constituting the cured product 42.

  Further, a cured product 43 of a thermosetting resin exists in the third space 33 formed by the upper surface of the solder resist 13 and the lower surface of the component main body 20. Therefore, the cured product 43 is interposed between the upper surface of the solder resist 13 and the lower surface of the component main body 20. On the other hand, no solder is present in the third space 33. Alternatively, even if solder is present in the third space 33, the amount thereof is about 5 vol%. Thus, the cured product 43 joins the solder resist 13 and the electronic component 2 to each other in the third space 33. In the present embodiment, the third space 33 is formed between the two electrode layers 21. The thermosetting resin that constitutes the cured product 43 is the same resin as the thermosetting resin that constitutes the cured product 42.

  In the component mounting board 10, each opening 14 is entirely covered with an electrode layer 21 corresponding to the opening 14. Therefore, the size of each opening 14 is smaller than the size of the opening 107 (see FIG. 9) of the conventional component mounting board corresponding to the opening 14. Specifically, the ratio of the area of each opening 14 to the area of the lower surface of the electrode layer 21 corresponding to the opening 14 is 50 to 100%. As shown in FIG. 9, in the conventional component mounting substrate, a part of each opening 107 is only covered with the electronic component 102.

  FIG. 2 is a cross-sectional view showing a component mounting board according to a second embodiment of the present invention. FIG. 3 is an enlarged view of a region III shown in FIG. As shown in FIG. 2, the component mounting board 310 includes a wiring board 301 and a land grid array (LGA) type electronic component 302 mounted on the wiring board 301. The electronic component 302 includes a substrate 320, a semiconductor element 321 mounted on the substrate 320, and an exterior body 322 that covers the semiconductor element 321 on the substrate 320.

  In the substrate 320, a plurality of first planar electrodes 323 (lands) are formed on the upper surface, and a plurality of second planar electrodes 324 (lands) are formed on the lower surface. The second planar electrodes 324 are arranged in a grid. A terminal (not shown) of the semiconductor element 321 is electrically connected to the first planar electrode 323. Further, as shown in FIG. 3, each first planar electrode 323 and the corresponding second planar electrode 324 are electrically connected to each other by a conductive via 325 that penetrates the substrate 320 from its upper surface to its lower surface. Yes. Thus, in the electronic component 302, the second planar electrode 324 constitutes a plurality of terminals exposed on the lower surface of the electronic component 302.

  As shown in FIGS. 2 and 3, the wiring substrate 301 includes an insulating substrate 311, a wiring layer 312 formed on the surface 311 a of the insulating substrate 311, and a solder resist 313 that covers the wiring layer 312. In the solder resist 313, a plurality of openings 314 corresponding to the second planar electrodes 324 one by one are formed. As shown in FIG. 3, the opening 314 exposes, from the solder resist 313, the bonding surface 312 a to which the second planar electrode 324 is electrically bonded in the surface of the wiring layer 312. On the other hand, each opening 314 is entirely covered with a second planar electrode 324 corresponding to the opening 314. Thereby, the space in the opening 314 is a space (first space 331) closed by the wiring layer 312 and the electronic component 302.

  The first space 331 is filled with the solder 341, and the second flat electrode 324 and the bonding surface 312 a are electrically bonded to each other by the solder 341. On the other hand, no thermosetting resin is present in the first space 331. Alternatively, even if a thermosetting resin is present in the first space 331, the amount is about 5 vol%. For the solder 341, for example, Sn-Bi or Sn-Bi-Ag low melting point solder is used.

  Further, as shown in FIG. 3, a cured product 342 of a thermosetting resin exists in the second space 332 formed by the upper surface of the solder resist 313 and the side surface of the electronic component 302. On the other hand, no solder is present in the second space 332. Alternatively, even if solder is present in the second space 332, the amount thereof is about 5 vol%. Specifically, the cured product 342 fills the corner formed by the solder resist 313 and the electronic component 302 in the second space 332 and spreads in a fillet shape around the corner. Thus, the cured product 342 joins the solder resist 313 and the electronic component 302 to each other in the second space 332. For example, an epoxy resin is used as the thermosetting resin constituting the cured product 342.

  Further, a cured product 343 of a thermosetting resin exists in the third space 333 formed by the upper surface of the solder resist 313 and the lower surface of the substrate 320. Therefore, the cured product 343 is interposed between the upper surface of the solder resist 313 and the lower surface of the electronic component 302. On the other hand, no solder is present in the third space 333. Alternatively, even if solder is present in the third space 333, the amount thereof is about 5 vol%. Thus, the cured product 343 joins the solder resist 313 and the electronic component 302 to each other in the third space 333. The thermosetting resin constituting the cured product 343 is the same resin as the thermosetting resin constituting the cured product 342.

  Similarly to the component mounting board 10, the entire opening 314 is also covered with the second planar electrode 324 corresponding to the opening 314 in the component mounting board 310. Therefore, the size of each opening 314 is smaller than the size of the opening of a conventional component mounting board having an LGA type electronic component. Specifically, the ratio of the area of each opening 314 to the area of the lower surface of the second planar electrode 324 corresponding to the opening 314 is 50 to 100%.

  Next, a method and system for manufacturing a component mounting board according to the present invention will be described.

  The manufacturing method includes an applying step for applying a solder paste, a mounting step for mounting an electronic component, and a heating step for heating the solder paste. In the applying step, a solder paste containing solder and a thermosetting resin is applied to the joint surface of the wiring board. In the mounting process, the electronic component is mounted on the wiring board so that the terminal of the electronic component covers the entire opening and contacts the solder paste applied to the joint surface. At this time, the electronic component is usually mounted on the wiring board with its lower surface being separated from the resist surface. After the mounting process is performed, in the heating process, the solder paste applied to the joint surfaces is heated to melt the solder and soften the thermosetting resin, and then cure the thermosetting resin.

  In addition, the application | coating process mentioned above, a mounting process, and a heating process are processes performed by the application | coating apparatus with which the manufacturing system demonstrated below is equipped, a mounting apparatus, and a heating apparatus, respectively.

  The manufacturing system includes an applying device for applying a solder paste, a mounting device for mounting an electronic component, and a heating device for heating the solder paste. The applying device applies a solder paste containing solder and a thermosetting resin to the joint surface of the wiring board. The mounting device mounts the electronic component on the wiring board so that the terminal of the electronic component covers the entire opening and contacts the solder paste applied to the joint surface. At this time, the mounting apparatus normally mounts the electronic component on the wiring board in a state where the lower surface thereof is separated from the surface of the resist. The heating device heats the solder paste applied to the joint surface, thereby melting the solder and softening the thermosetting resin, and then curing the thermosetting resin.

  According to the manufacturing method and the manufacturing system described above, the solder is melted by heating the solder paste and the thermosetting resin is softened, so that the electronic component comes close to the surface of the resist and the solder and the thermosetting resin are separated. As a result, the solder collects in the first space in the opening closed by the wiring layer and the electronic component, and the thermosetting resin collects in the second space formed by the upper surface of the resist and the side surface of the electronic component. Furthermore, the thermosetting resin collects in a third space formed by the upper surface of the resist and the lower surface of the electronic component.

  Thereafter, the thermosetting resin is cured by further heating of the solder paste. Thereafter, the solder is solidified in the cooling process. As a result, the wiring board and the electronic component are electrically joined to each other in the first space by the solidified solder. Moreover, when the thermosetting resin is cured, a cured product is formed in the second space and the third space. And with this hardened | cured material, a wiring board and an electronic component are mutually joined in 2nd space and 3rd space.

  In the specific configuration of the manufacturing method and the manufacturing system described above, the solder paste is applied to the bonding surface so that the total volume of the solder contained in the solder paste on the bonding surface is substantially the same as the volume of the first space. Process and applicator). Note that the ratio of the total volume of solder to the volume of the first space is preferably 95 to 100%.

  Hereinafter, as a specific example of the manufacturing system, a manufacturing system for manufacturing the component mounting board 10 shown in FIG. 1 will be specifically described with reference to the drawings. The manufacturing system described below can also be applied to the manufacture of the component mounting board 310 shown in FIG.

  FIG. 4 is a block diagram showing a production line constituting the production system. As shown in FIG. 4, the production line includes a substrate supply device 201 for supplying the wiring substrate 1, a solder paste applying device 202, a mounting device 203 for mounting the electronic component 2 on the wiring substrate 1, a heating device 204, A recovery device 205 that recovers the manufactured component mounting board 10 and a transfer device 206 that transfers the wiring board 1 between these devices are provided.

  FIG. 5 is a cross-sectional view showing a specific configuration of the production line. As shown in FIG. 5, the transport device 206 is configured by a conveyor having the transport belt 6. The transport device 206 is not limited to a conveyor, and various devices having a transport function can be used. Then, the wiring substrate 1 supplied from the substrate supply device 201 is placed on the transport belt 6. For the substrate supply device 201, for example, a magazine type substrate loader is used.

  The solder paste applying device 202 applies a solder paste 4 containing solder and a thermosetting resin to the wiring board 1. Specifically, the solder paste applying device 202 supplies the solder paste 4 to the bonding surface 12 a by supplying the solder paste 4 to the opening 14. At this time, the solder paste application device 202 has the total volume of solder contained in the solder paste 4 on each joint surface 12a substantially equal to the volume of the first space 31 (see FIG. 1) corresponding to the joint surface 12a. Thus, the solder paste 4 is supplied to the opening 14. The ratio of the total solder volume to the volume of the first space 31 is preferably 95 to 100%.

  In the present embodiment, as described above, the size of the opening 14 is smaller than the size of the opening 107 (see FIG. 9) of the conventional component mounting board. Therefore, if the thickness of the solder resist 13 is the same as the thickness of the solder resist 110 (see FIG. 9) of the conventional component mounting board, the following problem occurs. That is, when the same amount of solder paste 4 applied to each opening 107 in the manufacturing process of the conventional component mounting substrate is applied to each opening 14, the solder contained in the applied solder paste 4 Is larger than the volume of the first space 31 corresponding to the opening 14. For this reason, in the component mounting board to be manufactured, the solder overflows from the first space 31, and the solder and the thermosetting resin come into contact with each other.

  Therefore, in the present embodiment, the thickness of the solder resist 13 is set large so that the volume of each first space 31 matches the total volume of the solder. Specifically, this thickness is, for example, 30 to 70 μm. Alternatively, the amount of solder paste 4 applied to each opening 14 is adjusted to be small by the solder paste applying device 202 so that the total volume of the solder matches the volume of each first space 31. The solder paste 4 may be prepared so that the solder content in the solder paste 4 is reduced so that the total volume of the solder matches the volume of each first space 31.

  For example, Sn-Bi-based or Sn-Bi-Ag-based low melting point solder and epoxy resin are used for the solder and the thermosetting resin constituting the solder paste 4, respectively. In addition, the solder paste 4 may contain an activator or a thixotropic agent as necessary. Note that the solder and the thermosetting resin are not limited to these materials. However, the epoxy resin is suitable as a thermosetting resin to be used because it is easy to handle, the strength of the cured product is high, and the curing characteristics are good.

  In the present embodiment, a screen printing apparatus is used as the solder paste applying apparatus 202. FIG. 5 shows a mask 7 for screen printing. In the solder paste application device 202, the position of the mask 7 is adjusted based on the position and orientation of the wiring board 1, and thereby the position to which the solder paste 4 is applied is adjusted. The solder paste applying device 202 may be a printing device (for example, an ink jet printer) having a printing nozzle or a coating device having a coating head (needle or nozzle) and a dispenser.

  The mounting device 203 mounts the electronic component 2 at a mounting position on the wiring board 1. As shown in FIG. 6, each electrode layer 21 of the electronic component 2 covers the entire opening 14 corresponding to the electrode layer 21 and is attached to the bonding surface 12 a corresponding to the electrode layer 21 as shown in FIG. 6. The position is such that it contacts the solder paste 4. The mounting device 203 mounts the electronic component 2 on the wiring board 1 in a state where the lower surface of the electrode layer 21 is separated from the surface of the solder resist 13 by a predetermined distance L. As an example, the mounting device 203 includes an electronic component supply device and a chip mounter that places the electronic component 2 supplied from the electronic component supply device at the mounting position. Devices such as a tape feeder, a bulk feeder, and a tray feeder can be used as the electronic component supply device. In addition, a device such as a suction nozzle can be used for the chip mounter.

  As shown in FIG. 6, immediately after the electronic component 2 is mounted at the mounting position on the wiring board 1, the solder 41 is dispersed throughout the solder paste 4. Further, there is a gap 8 between the electrode layer 21 and the solder resist 13.

  The heating device 204 heats the solder paste 4 applied to the bonding surface 12a, thereby melting the solder 41 in the solder paste 4 and softening the thermosetting resin 44 (see FIG. 6) in the solder paste 4. Let Here, the solder resist 13 has a property that the molten solder 41 hardly adheres to the surface, in other words, a property that it is easy to play the molten solder 41. Therefore, as shown in FIG. 7, the melted solder 41 moves through the gap 8 to a place where the solder resist 13 does not exist (specifically, in the opening 14). In FIG. 7, the movement of the solder 41 is indicated by solid arrows.

  The solder 41 has a higher specific gravity than the thermosetting resin 44. Accordingly, as shown in FIG. 7, the solder 41 moves downward in the opening 14, whereby the solder 41 is accumulated on the joint surface 12 a. On the other hand, as the solder 41 moves into the opening 14, the thermosetting resin 44 in the opening 14 is driven out of the opening 14. Then, the thermosetting resin 44 moves onto the solder resist 13 through the gap 8. In FIG. 7, the movement of the thermosetting resin 44 is indicated by broken line arrows.

  As the solder 41 and the thermosetting resin 44 move, the electronic component 2 comes close to the surface of the solder resist 13. Each opening 14 is closed by the electrode layer 21 corresponding to the opening 14, thereby forming a first space 31 (see FIG. 1). Accordingly, a second space 32 and a third space 33 (see FIG. 1) are formed on the solder resist 13. Accordingly, the electronic component 2 blocks the space between the first space 31 and the second space 32 and the space between the first space 31 and the third space 33.

  Thus, the solder 41 is collected in the first space 31, but the thermosetting resin 44 is not included. Alternatively, even if the first space 31 contains the thermosetting resin 44, the amount is about 5 vol%. Further, the thermosetting resin 44 collects in the second space 32 and the third space 33 while the solder 41 is not included. Or even if the solder 41 is contained in the 2nd space 32 and the 3rd space 33, the quantity is about 5 vol%.

  Thereafter, the heating device 204 further heats the solder paste 4 to cure the thermosetting resin 44. Thereafter, the solder 41 is solidified in the cooling process. As a result, the wiring board 1 and the electronic component 2 are electrically joined to each other in the first space 31 by the solidified solder 41. Further, the thermosetting resin 44 is cured, whereby cured products 42 and 43 are formed in the second space 32 and the third space 33, respectively. Then, the cured products 42 and 43 join the wiring board 1 and the electronic component 2 to each other in the second space 32 and the third space 33.

  In this manner, the component mounting board 10 shown in FIG. 1 is manufactured.

  The collection device 205 collects the manufactured component mounting board 10 from the conveyance belt 6. For example, a magazine-type substrate unloader is used for the collection device 205.

  In the production line, the substrate supply device 201, the solder paste applying device 202, the mounting device 203, the heating device 204, and the recovery device 205 are configured separately and independently. However, the configuration of the production line is not limited to this, and instead of some or all of these apparatuses, a composite apparatus having these functions may be used.

  In the component mounting board 10, the electronic component 2 blocks the space between the first space 31 and the second space 32 and the space between the first space 31 and the third space 33. For this reason, the second space 32 and the third space 33 are formed at positions separated from the first space 31 along the upper surface of the solder resist 13. Therefore, the cured product 42 in the second space 32 and the cured product 43 in the third space 33 do not contact the solder 41 in the first space 31.

  Therefore, in the repair process for the component mounting board 10, when the electronic component 2 is removed from the wiring board 1 as shown in FIG. 8, the solder 41 and the thermosetting resin 44 remain on the wiring board 1, but the solder 41 Is located in the first opening 14, and the thermosetting resin 44 is located on the upper surface of the solder resist 13 without contacting the solder 41. For this reason, even when a new electronic component 2 is remounted, the thermosetting resin hardly mixes in the solder. Therefore, even when a repair process is performed on the component mounting board 10, it is difficult for a bonding failure to occur between the wiring board 1 and the electronic component 2.

  In the component mounting board 10, the wiring board 1 and the electronic component 2 are joined to each other in the first space 31 by the solder 41. In addition, the wiring board 1 and the electronic component 2 are joined to each other by the cured product 42 in the second space 32 and are joined to each other by the cured product 43 in the third space 33. Therefore, in the component mounting board 10, the bonding strength between the wiring board 1 and the electronic component 2 is high.

  In the conventional component mounting substrate shown in FIG. 9, the opening 107 exposes a bonding surface 109 on the surface of the wiring layer 108 to which the electronic component 102 is electrically bonded from the solder resist 110. The electronic component 102 is electrically bonded to the bonding surface 109 via the solder fillet 103 with both ends thereof floating from the bonding surface 109. Therefore, when applying the solder paste for forming the solder fillet 103 to the two joint surfaces 109 in the manufacturing process of the conventional component mounting board, the amount of solder paste applied to the two joint surfaces 109 is different from each other. The following phenomenon is likely to occur. That is, after the solder is melted by heating to the solder paste, one end of the electronic component 102 is pulled toward the bonding surface 109 due to the difference in solidification speed caused by the difference in applied amount when the solder is solidified. As a result, the electronic component 102 is tilted.

  On the other hand, in the component mounting board 10, both ends of the electronic component 2 are located on the surface of the solder resist 13. Therefore, even if one end of the electronic component 2 is pulled downward, the solder resist 13 prevents the one end from moving downward. Therefore, the electronic component 2 is difficult to tilt.

  In addition, each part structure of this invention is not restricted to the said embodiment, A various deformation | transformation is possible within the technical scope as described in a claim. For example, in the component mounting board 10 shown in FIG. 1, the electronic component 2 may be arranged slightly shifted from the mounting position on the wiring board 1. In this case, a part of each opening 14 may not be covered by the electrode layer 21 corresponding to the opening 14, but even if this is the case, the whole opening 14 is not covered by the electronic component 2. That's fine.

  2 can also be applied to the configuration of a component mounting board including a ball grid array (BGA) type electronic component. Furthermore, each part structure of the component mounting board | substrate mentioned above is applicable also to the structure of the various component mounting board | substrates which are not limited to the component mounting board | substrate shown by FIG. 1 and FIG.

  The component mounting board according to the present invention can be mounted on an electronic device such as a liquid crystal display module.

DESCRIPTION OF SYMBOLS 1 Wiring board 2 Electronic component 10 Component mounting board 11 Insulating board 11a Surface 12 Wiring layer 12a Joint surface 13 Solder resist 14 Opening 20 Component main body 21 Electrode layer (terminal)
31 1st space 32 2nd space 33 3rd space 41 Solder 42, 43 Cured material 44 Thermosetting resin 301 Wiring board 302 Electronic component 310 Component mounting board 311 Insulating board 311a Surface 312 Wiring layer 312a Bonding surface 313 Solder resist 314 Opening 320 Substrate 321 Semiconductor element 322 Exterior body 323 First planar electrode 324 Second planar electrode (terminal)
325 Conductive via 331 First space 332 Second space 333 Third space 341 Solder 342, 343 Hardened material

Claims (6)

A wiring board;
An electronic component mounted on the wiring board,
The wiring board includes an insulating substrate, a wiring layer formed on a surface of the insulating substrate, and a resist covering the wiring layer, and an opening is formed in the resist, and the opening is a surface of the wiring layer. While exposing the bonding surface to which the terminals of the electronic component are electrically bonded from the resist, the entire opening is covered with the electronic component,
A first space in the opening closed by the wiring layer and the electronic component is filled with solder, and the terminal and the joint surface are electrically joined to each other by the solder, and the upper surface of the resist and the resist In the second space formed by the side surface of the electronic component, a cured product of a thermosetting resin joins the resist and the electronic component to each other.
Component mounting board.   The component mounting board according to claim 1, wherein the entire opening is covered with the terminals of the electronic component.   The thermosetting resin does not exist in the first space, or even if the thermosetting resin exists in the first space, the amount thereof is 5 vol% or less. The component mounting board according to claim 2.   4. The device according to claim 1, wherein the solder does not exist in the second space, or even if the solder exists in the second space, the amount thereof is 5 vol% or less. 5. The component mounting board described in 1.   Furthermore, in the 3rd space formed by the upper surface of the said resist, and the lower surface of the said electronic component, the hardened | cured material of the said thermosetting resin has joined the said resist and the said electronic component mutually. The component mounting board according to claim 4.   The component mounting board according to claim 5, wherein the solder does not exist in the third space, or even if the solder exists in the third space, the amount thereof is 5 vol% or less.

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