JP2016092261A - Electronic controller and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic controller capable of suppressing both generation of voids in a sealing resin, and occurrence of breakdown of a mounted electronic component, and to provide a method of manufacturing an electronic controller.SOLUTION: An electronic controller includes a substrate 1, an electronic component 5, and a sealing resin 9. The electronic component 5 is mounted on the principal surface of the substrate 1. The sealing resin 9 is supplied by transfer mold method. A through hole 21 penetrating the substrate 1 is formed in the substrate 1, so as to overlap at least a part of the electronic component 5, and to extend in a direction crossing the principal surface. The through hole 21 is formed to surround the periphery of an electrode pad 11 formed on the principal surface, for the purpose of electrical connection with the electronic component 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electronic control device and a manufacturing method thereof, and more particularly to an electronic control device sealed with a resin by a transfer molding method and a manufacturing method thereof.

  Electronic control devices such as inverter modules used in electric vehicles and hybrid vehicles generate a large amount of heat due to a request for flowing a large current. In addition, with the increase in electronic control devices in today's vehicle interiors, it has begun to be required to install electronic control devices in environments where the temperature conditions are extremely severe, such as engine rooms. For this reason, the electronic control device is required to have high heat resistance, air tightness and reliability including them.

  Therefore, the electronic control device is sealed with a resin from the viewpoint of increasing its reliability. For example, Japanese Patent Application Laid-Open No. 4-137657 (Patent Document 1) discloses a hybrid integrated circuit board in which an electronic circuit board on which a surface-mount type electronic component is mounted is sealed with a resin.

JP-A-4-137657

  In Japanese Patent Laid-Open No. 4-137657, a resin that seals the insulating substrate is particularly insulated by providing a through hole immediately below a region where an electronic component is mounted on the insulating substrate (electronic circuit substrate). The possibility of forming voids between the conductive substrate and the electronic component (on the main surface on the back side of the substrate) is reduced.

  However, in Japanese Patent Laid-Open No. 4-137657, resin sealing is performed by immersing an insulating substrate in a mold resin solution in the atmosphere. For this reason, even if a through hole is provided directly under the electronic component, it is difficult to eliminate voids in the sealing resin. Further, for the purpose of further void reduction, when a so-called transfer molding method is used, when an insulating substrate provided with a through hole directly under an electronic component is sealed with a resin as disclosed in JP-A-4-137657, There is a possibility that an electronic component made of a brittle material mounted on the insulating substrate is damaged by the pressure of the flowing sealing resin.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an electronic control device capable of suppressing both the generation of voids in the sealing resin and the occurrence of breakage of the mounted electronic component, and It is to provide a method for manufacturing the electronic control device.

  The electronic control device of the present invention includes a substrate, an electronic component, and a sealing resin. The electronic component is mounted on the main surface of the substrate. The sealing resin is supplied by a transfer molding method. A through-hole penetrating the substrate is formed so as to extend in a direction intersecting the main surface so as to overlap at least a part of the electronic component. The through hole is formed so as to surround the periphery of the electrode pad formed on the main surface from at least two directions in order to make electrical connection with the electronic component.

  In the method for manufacturing an electronic control device of the present invention, first, a through hole is formed in a substrate. Electrode pads for electrical connection with electronic components are formed on the main surface of the substrate. Electronic components are mounted on the main surface. A substrate on which electronic components are mounted is resin-sealed by a transfer molding method. The electrode pad is formed so as to be surrounded by the through hole from at least two directions. The electronic component is mounted so as to overlap at least a part of the through hole.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the void of the electronic component resulting from the pressure at the time of resin sealing can be suppressed while it can suppress generation | occurrence | production of the void in the area | region which overlaps with an electronic component especially.

1 is a schematic cross-sectional view showing a configuration of an electronic control device according to Embodiment 1. FIG. It is a schematic plan view which shows the aspect in planar view of the through-hole and electrode pad in the area | region P enclosed with the dotted line of FIG. FIG. 3 is a schematic plan view showing a mode in which brittle electronic components are superimposed on through holes and electrode pads in a region P of FIG. 1 as in FIG. 2. FIG. 3 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 3 showing a first step of the method for manufacturing the electronic control device according to the first embodiment, and a method for manufacturing the electronic control device according to the first embodiment. FIG. 3 is a schematic cross-sectional view (B) of a portion along line BB in FIG. 3 showing one step, and a line CC in FIG. 3 showing a first step in the method for manufacturing the electronic control device of the first embodiment. It is a schematic sectional drawing (C) of the part which follows. FIG. 3 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 3 showing a second step of the method for manufacturing the electronic control device according to the first embodiment, and a second method for manufacturing the electronic control device according to the first embodiment. FIG. 3 is a schematic cross-sectional view (B) of a portion along line B-B in FIG. 3 showing two steps, and a line C-C in FIG. 3 showing a second step of the method for manufacturing the electronic control device of the first embodiment. It is a schematic sectional drawing (C) of the part which follows. FIG. 3 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 3 showing a third step of the method for manufacturing the electronic control device according to the first embodiment, and a method for manufacturing the electronic control device according to the first embodiment. 3 is a schematic cross-sectional view (B) of a portion along the line B-B in FIG. 3, and a line C-C in FIG. 3, which shows a third step of the method for manufacturing the electronic control device of the first embodiment. It is a schematic sectional drawing (C) of the part which follows. FIG. 3 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 3 showing a fourth step of the method for manufacturing the electronic control device according to the first embodiment, and a method for manufacturing the electronic control device according to the first embodiment. FIG. 3 is a schematic cross-sectional view (B) of a portion along the line BB in FIG. 3 showing the four steps, and a line CC in FIG. 3 showing the fourth step of the method for manufacturing the electronic control device of the first embodiment. It is a schematic sectional drawing (C) of the part which follows. FIG. 3 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 3 showing the fifth step of the method for manufacturing the electronic control device according to the first embodiment, and the method for manufacturing the electronic control device according to the first embodiment. A schematic sectional view (B) of a portion along the line BB in FIG. 3 showing five steps, and a line CC in FIG. 3 showing a fifth step of the method for manufacturing the electronic control device of the first embodiment. It is a schematic sectional drawing (C) of the part which follows. FIG. 3 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 3 showing a sixth step of the method for manufacturing the electronic control device according to the first embodiment, and a method for manufacturing the electronic control device according to the first embodiment. A schematic sectional view (B) of a portion along the line BB in FIG. 3 showing the six steps, and a line CC in FIG. 3 showing the sixth step of the method for manufacturing the electronic control device of the first embodiment. It is a schematic sectional drawing (C) of the part which follows. It is a schematic sectional drawing which shows the structure of the electronic control apparatus of a comparative example. FIG. 11 is a schematic plan view showing a mode in which brittle electronic components are superimposed on a through hole and an electrode pad in a region P surrounded by a dotted line in FIG. 10. FIG. 11 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 11 showing the first step of the method for manufacturing the electronic control device of the comparative example, and shows the first step of the method for manufacturing the electronic control device of the comparative example. FIG. 11 is a schematic cross-sectional view (B) of the portion along the line BB in FIG. 11 and a schematic cross-sectional view of the portion along the line CC in FIG. 11 showing the first step of the method of manufacturing the electronic control device of the comparative example. (C). FIG. 11 is a schematic cross-sectional view (A) of the portion along the line AA in FIG. 11 showing the second step of the method for manufacturing the electronic control device of the comparative example, and shows the second step of the method for manufacturing the electronic control device of the comparative example. FIG. 11 is a schematic cross-sectional view (B) of the portion along the line BB in FIG. 11 and a schematic cross-sectional view of the portion along the line CC in FIG. 11 showing the second step of the method for manufacturing the electronic control device of the comparative example. (C). FIG. 11 is a schematic cross-sectional view (A) of a portion along the line AA in FIG. 11 showing the third step of the method for manufacturing the electronic control device of the comparative example, and shows the third step of the method for manufacturing the electronic control device of the comparative example. FIG. 11 is a schematic cross-sectional view (B) of the portion along the line BB in FIG. 11 and a schematic cross-sectional view of the portion along the line CC in FIG. 11 showing the third step of the method of manufacturing the electronic control device of the comparative example. (C). FIG. 11 is a schematic cross-sectional view (A) of a portion along line AA in FIG. 11 showing a fourth step of the method for manufacturing the electronic control device of the comparative example, and shows a fourth step of the method for manufacturing the electronic control device of the comparative example. FIG. 11 is a schematic cross-sectional view (B) of the portion along the line BB in FIG. 11 and a schematic cross-sectional view of the portion along the line CC in FIG. 11 showing the fourth step of the method of manufacturing the electronic control device of the comparative example. (C). FIG. 6 is a schematic plan view showing a first example of an aspect in a plan view of a through hole and an electrode pad in a region P surrounded by a dotted line in FIG. 1 of the electronic control device of the second embodiment. FIG. 6 is a schematic plan view showing a second example of a mode of the through hole and the electrode pad in a plan view of a region P surrounded by a dotted line in FIG. 1 of the electronic control device according to the second embodiment. FIG. 6 is a schematic cross-sectional view illustrating a configuration of an electronic control device according to a third embodiment. It is a schematic plan view which shows the 1st example of the aspect in planar view of the through-hole and electrode pad in the area | region P enclosed with the dotted line of FIG. It is a schematic plan view which shows the 2nd example of the aspect in planar view of the through-hole and electrode pad in the area | region P enclosed with the dotted line of FIG. FIG. 6 is a schematic cross-sectional view showing a configuration of an electronic control device according to a fourth embodiment. FIG. 10 is a schematic cross-sectional view showing the operation of the electronic control device according to the fourth embodiment. FIG. 16 is a schematic plan view showing a planar view of a through hole and an electrode pad in a region P similar to FIG. 2 in the first example of the fifth embodiment. FIG. 10 is a schematic plan view showing a plan view of through holes and electrode pads in a region P similar to FIG. 2 in a second example of the fifth embodiment. FIG. 10 is a schematic plan view showing a plan view of through holes and electrode pads in a region P similar to FIG. 2 in a third example of the fifth embodiment. FIG. 10 is a schematic plan view showing a plan view of through holes and electrode pads in a region P similar to FIG. 2 in a fourth example of the fifth embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Embodiment 1)
First, the configuration of the electronic control device 100 according to the present embodiment will be described with reference to FIGS.

  With reference to FIG. 1, an electronic control device 100 of the present embodiment mainly includes an electronic circuit board 1 (substrate), a brittle electronic component 5 (electronic component), and a sealing resin 9.

  The electronic circuit board 1 is an insulating board such as a glass epoxy board, which is a general printed circuit board, and is a member that forms the foundation of the electronic control device 100. Various electronic components and the like can be mounted on the main surface of the electronic circuit board 1. Here, the brittle electronic component 5 and the normal electronic component 15 are mounted.

  The brittle electronic component 5 is a component that houses a semiconductor device such as a power semiconductor element, and is mounted (mounted) on the main surface 1 a on the upper side of the electronic circuit board 1, for example. The package that houses the semiconductor device at the outermost periphery of the brittle electronic component 5 is made of a brittle material that is easily damaged by application of pressure, such as ferrite.

  On the other hand, the normal electronic component 15 is not formed of a brittle material like the brittle electronic component 5 here (is not as easily damaged as the brittle electronic component 5), and is a generally known chip component. The normal electronic component 15 is generally smaller in size in plan view than the brittle electronic component 5. Conversely, the brittle electronic component 5 is generally larger than the normal electronic component 15 in plan view. From this point of view, the brittle electronic component 5 is more likely to be damaged than a normal electronic component 15 by a force applied from above, for example.

  Referring to FIG. 2, electrode pad 11 is formed on main surface 1a of electronic circuit board 1 (for example, on the upper side in FIG. 1). The electrode pad 11 is a pad that is electrically connected to the electronic components 5 and 15 by connecting the terminals of the brittle electronic component 5 and the normal electronic component 15. For example, a plurality of electrode pads 11 are arranged on the main surface of the electronic circuit board 1 so as to be arranged at a distance from each other along a linear axis l extending in one direction (left-right direction in FIG. 2). For example, the region has a rectangular shape in plan view. The electrode pad 11 is electrically connected to a circuit or the like formed in the electronic circuit board 1, and for example, a pair of terminals (for example, an input terminal and an output terminal) of the brittle electronic component 5 are connected thereto. The semiconductor device in the brittle electronic component 5 and the circuit formed in the electronic circuit board 1 are electrically connected.

  Specifically, for example, the brittle electronic component 5 includes an input terminal and an output terminal, and these input terminal and output terminal are in contact with each of the pair of electrode pads 11. The input terminal and the output terminal of the brittle electronic component 5 are electrically and mechanically connected to each of the pair of electrode pads 11 by, for example, solder 13.

  The sealing resin 9 is a resin material formed so as to cover (seal) the surface of the electronic circuit board 1 on which the brittle electronic component 5 or the like is mounted, and is, for example, a thermosetting resin such as an epoxy resin. Is preferred. The sealing resin 9 covers the entire surface of the electronic circuit board 1 and the brittle electronic component 5 mounted thereon, and covers the surface of the brittle electronic component 5 and the like between the sealing resin 9 and the brittle electronic component 5. It is formed in the mode.

  With reference to FIGS. 1 and 2, a through hole 21 is formed in the electronic circuit board 1. This through hole 21 extends from the upper main surface 1a in FIG. 1 to the lower main surface in FIG. 1 so as to extend in a direction intersecting the main surface of the electronic circuit substrate 1 (vertical direction in FIG. 1). Up to 1b is a void region formed so as to penetrate through the electronic circuit board 1 and from which the material constituting the electronic circuit board 1 has been removed. Therefore, the inside of the through hole 21 is filled with the sealing resin 9.

  Referring to FIGS. 2 and 3, the through-hole 21 is formed in the vertical direction of FIGS. 2 and 3 (in the depth direction of FIG. 1 in a plan view) in a region sandwiched between the pair of electrode pads 11. ). Furthermore, the through-hole 21 is formed so as to extend in the left and right direction of each figure (left and right direction in FIG. 1) in each of the upper and lower regions of the pair of electrode pads 11 in FIGS. 2 and 3 in plan view. Has been.

  Accordingly, the through hole 21 is formed so as to surround each of the pair of electrode pads 11 from three directions in plan view. Here, the three directions are arbitrarily selected from a total of four directions of the positive and negative bidirectional directions of the electrode pad 11 in the X direction and the Y direction when the electronic circuit board 1 is viewed in plan as shown in FIGS. Means. That is, the electrode pad 11 on the left side in FIGS. 2 and 3 has a mode in which the three directions on the upper side, the lower side, and the right side are surrounded by the through holes 21. Further, the right electrode pad 11 in FIGS. 2 and 3 has a mode in which three directions of the upper side, the lower side, and the left side are surrounded by the through hole 21.

  Thus, the through-hole 21 has a long planar shape extending in the three directions around the electrode pad 11 in a direction intersecting (for example, perpendicular) to the normal line extending from the electrode pad 11 to each of the three directions. Preferably, it has a shape like a letter “H” in plan view.

  Referring to FIG. 3, if brittle electronic component 5 is mounted immediately above electrode pad 11 and through hole 21 shown in FIG. 2, each of a pair of terminals of brittle electronic component 5 is a pair of electrode pads 11. The brittle electronic component 5 is disposed so as to straddle the pair of electrode pads 11. Since the through hole 21 is formed in a region sandwiched between the pair of electrode pads 11, the brittle electronic component 5 and the through hole 21 are arranged to overlap each other particularly in this region. Thus, the through hole 21 is formed so as to overlap with at least a part of the brittle electronic component 5 in a planar manner.

  In FIG. 3, the through-hole 21 overlaps the brittle electronic component 5 in a planar manner (arranged immediately below the brittle electronic component 5), and a non-overlapping region 21 </ b> B does not overlap the brittle electronic component 5 in a planar manner. have. As described above, the through hole 21 is partially formed in a region overlapping the brittle electronic component 5 in plan view, but part of the through hole 21 is formed in a region other than the region overlapping the brittle electronic component 5 in plan view. .

  In FIG. 1 and FIG. 3, a through hole 21 is formed in a region overlapping with a region sandwiched between a pair of electrode pads 11 connected to a brittle electronic component 5, and a pair of connected to a normal electronic component 15. A through hole 21 is not formed in a region overlapping the region sandwiched between the electrode pads 11. However, a region overlapping the region sandwiched between the pair of electrode pads 11 connected to the normal electronic component 15 is included (for example, the brittle electronic component 5 in FIG. 3 is replaced with the normal electronic component 15). ) A through hole 21 may be formed.

  Referring to FIG. 2 again, the through holes 21 formed around the electrode pads 11 are formed so as to be symmetric with respect to the arrangement of the pair of electrode pads 11. Specifically, in a plan view with respect to a linear axis l passing through the central portion of the electrode pad 11 in a direction intersecting with the direction in which the pair of electrode pads 11 connected to the brittle electronic component 5 are arranged (up and down in FIG. 2). A through hole 21 is formed so as to be symmetrical.

  Next, the manufacturing method of the electronic control apparatus 100 of this Embodiment is demonstrated using FIGS. In addition, (A) of each figure is shown passing through the area | region where each of a pair of electrode pad 11 and the brittle electronic component 5 is formed. Moreover, (B) of each figure passes through the area | region in which the through-hole 21 extended in an up-down direction is formed in the area | region between the pair of electrode pads 11 of FIG. 3, (C) of each figure. 3 partially passes through the region where the left electrode pad 11 and the brittle electronic component 5 just above the electrode pad 11 are formed.

  4A, 4B, and 4C, first, an electronic circuit board 1 as a generally known printed circuit board is prepared, and an electronic circuit from one main surface 1a to the other main surface 1b is prepared. A through hole 21 is formed so as to penetrate the substrate 1.

  The through hole 21 has a shape like a letter “H” shown in FIGS. 2 and 3 in plan view. For this reason, in the cross-sectional view of FIG. 4A, there is one through-hole 21 having a narrow width (having a width equal to the width in the horizontal direction of the through-hole 21 extending in the vertical direction in FIG. 2). On the other hand, the cross-sectional view of FIG. 4B is wider than FIG. 4A (the through hole 21 extending in the vertical direction in FIG. 2 has a width equal to the length extending in the vertical direction). There is one through hole 21. In the cross-sectional view of FIG. 4C, there are two through holes 21 each having a width equal to the width extending in the vertical direction of FIG. 2 of each of the two through holes 21 extending in the horizontal direction of FIG. The through hole 21 is formed by pressing or drilling.

  Referring to FIGS. 5A, 5B, and 5C, for example, an electron is inserted so as to sandwich a part of through hole 21 of electronic circuit board 1 (a part in which through hole 21 in FIG. 2 extends in the vertical direction). On one main surface 1a of the circuit board 1, a pair of electrode pads 11 are formed at a distance from each other. The brittle electronic component 5 is mounted on, for example, the main surface 1a of the electronic circuit board 1 so as to be electrically connected to one and the other of the pair of electrode pads 11.

  Specifically, first, a solder paste as a material of the solder 13 is printed on each surface of the pair of electrode pads 11. The brittle electronic component 5 is mounted on the main surface 1a of the electronic circuit board 1 by the mounter so that the terminals included therein are in contact with the solder paste. Thereafter, the hot paste is directly applied to the electronic circuit board 1 to melt the solder paste to form the solder 13, and the solder 13 connects the terminal of the brittle electronic component 5 to the electrode pad 11. Thus, the brittle electronic component 5 is mounted on the electronic circuit board 1 by a so-called reflow process using the solder 13.

  When the solder paste is melted, hot air is supplied through the through holes 21 of the electronic circuit board 1 and the molten solder 13 is supplied, so that the brittle electronic component 5 is placed on the electronic circuit board 1 (the electrode pad 11). It is preferable to be adhered to.

  5A, 5B, and 5C, as shown in FIG. 2, the electrode pad 11 has three directions around each of the pair of electrode pads 11 in a plan view through the through hole 21. As shown in FIG. It is formed so as to surround from. Further, as shown in FIG. 3, the brittle electronic component 5 is arranged so as to overlap at least a part of the through hole 21 (the through hole 21 in the region sandwiched between the pair of electrode pads 11 in FIG. 3) in a plan view. Mounted on the main surface 1 a of the circuit board 1.

  The normal electronic component 15 may also be mounted (mounted) so as to overlap with the through-holes 21 surrounding the three directions around the electrode pad 11 connecting the same as the brittle electronic component 5. Further, the brittle electronic component 5 may be formed on the main surface 1 b of the electronic circuit board 1.

  6A, 6B, and 6C, the electronic circuit board 1 on which the brittle electronic component 5 is mounted is fitted to, for example, the transfer mold dies 31 that have been heated to a predetermined temperature in advance. It is installed in a space region 31a formed between the upper mold and the lower mold to be joined. Next, with reference to FIG. 6A in particular, the plunger 33 is inserted into a cylinder communicating with the space region 31a of the transfer mold 31. The sealing material tablet 35 is inserted into a region between the plunger 33 and the space region 31a (just above the plunger 33 in FIG. 6A) in the cylinder. The sealing material tablet 35 is made of a solid resin for sealing.

  With reference to FIGS. 7A, 7B, and 7C, particularly FIG. 7A, the plunger 33 is gradually pushed so as to move upward in the cylinder. As a result, the sealing material tablet 35 directly above the plunger 33 is pressurized and gradually guided into the space region 31a continuous with the cylinder while increasing the fluidity. Therefore, a resin material for sealing the sealing material tablet 35 is injected into the space region 31a.

  Referring to FIGS. 8A, 8B, and 8C, a so-called transfer molding method in which a resin material constituting sealing material tablet 35 is injected into space region 31a in transfer mold die 31 while being pressurized. Is processed. With reference to FIGS. 9A, 9B, and 9C, the space region 31a is filled with the resin material. Since the transfer mold 31 is heated, the resin material in the space region 31a is cured by this heat, and the electronic circuit board 1 is sealed so as to be covered with the solidified resin material (sealing resin 9). Is done.

Next, the effect of this Embodiment is demonstrated using the comparative example of FIGS.
Referring to FIGS. 10 to 11, electronic control apparatus 900 in the comparative example basically has the same configuration as electronic control apparatus 100 of the present embodiment in FIG. 1. However, in the electronic control device 900, the through hole 20 formed in the electronic circuit board 1 does not have a planar shape surrounding the electrode pad 11 from three directions like the through hole 21 of the present embodiment. A part of the region sandwiched between the pair of electrode pads 11 is formed to have, for example, a circular planar shape.

  In addition, since the structure of the comparative example other than this is substantially the same as the structure of Embodiment 1, the same code | symbol is attached | subjected about the same element and the description is not repeated.

  Referring to FIGS. 12 to 15, these show a manufacturing method of electronic control device 900, and steps corresponding to the steps shown in FIGS. 6 to 9 of the manufacturing method of electronic control device 100 of the present embodiment. Is shown. Basically, the electronic circuit board 1 on which the brittle electronic component 5 is mounted is installed in the space region 31a of the transfer mold 31 as in each step of FIGS. 6 to 9, and the plunger 33 and the sealing material tablet The sealing resin 9 is supplied into the space region 31 a by 35.

  At this time, for example, as shown in FIG. 14A, the sealing resin 9 that has flowed to the region directly above the brittle electronic component 5 is directed downward toward the brittle electronic component 5 by the pressure during the transfer molding process. A large force F may be applied instantaneously. At this time, since the brittle electronic component 5 is pressurized from only one direction, it may be damaged by the force F as shown in FIG. In particular, the above damage is a serious problem in brittle electronic parts 5 such as choke coils, transformers, and cement resistors using brittle materials such as ferrite or ceramics. For example, expensive electronic parts with high pressure resistance are used as countermeasures. There is a need to.

  On the other hand, in the present embodiment, for example, as shown in FIG. 8A, the sealing resin 9 that has flowed to the region immediately above the brittle electronic component 5 is directed downward toward the brittle electronic component 5 by the pressure. Even if a large force F is momentarily applied, the electronic circuit board 1 around the electrode pad 11 is deformed so as to be easily bent due to the planar shape of the through-hole 21, and the pressure F is released. That is, as compared with the electronic circuit board 1 in which only the circular through-hole 20 is formed as in the comparative example, the electrode pad 11 has a planar shape formed so as to surround the electrode pad 11 from three directions as in the present embodiment. The electronic circuit board 1 in which the through holes 21 are formed has a large force to absorb pressure from above.

  For this reason, in the present embodiment, the pressure F of the sealing resin 9 applied to the brittle electronic component 5 can be easily reduced, and the breakage of the brittle electronic component 5 can be suppressed as shown in FIG. A highly reliable electronic control device 100 can be provided. Therefore, an inexpensive and general-purpose brittle electronic component 5 can be used without using an expensive electronic component with high pressure resistance, and an increase in the manufacturing cost of the electronic control device 100 can be suppressed.

  Further, if a through hole is not formed in the electronic circuit board 1 directly below the brittle electronic component 5, for example, the sealing resin 9 is used in the resin sealing step (for example, see FIG. 14A) by the transfer molding method. However, it is difficult to enter the back side of the brittle electronic component 5, that is, the region sandwiched between the electronic circuit board 1 and the brittle electronic component 5, and an air layer (void) may be formed in the region. Since the air layer has a heat insulating property, it becomes difficult to release the heat generated by the brittle electronic component 5 accumulated in the region to the outside, which may reduce the reliability of the entire electronic control device 100.

  Further, when a void is generated so as to cover part or all of the surfaces of the brittle electronic component 5 and the electronic circuit board 1, the sealing resin 9 cannot contact the brittle electronic component 5 and the electronic circuit board 1 in the region. . For this reason, a mismatch in linear expansion coefficient occurs between the area where the sealing resin 9 contacts the brittle electronic component 5 and the electronic circuit board 1 and the area where the sealing resin 9 cannot contact. Thereby, the lifetime of the joint part by the solder 13 for mounting the brittle electronic component 5 on the electronic circuit board 1 is shortened, and there is a possibility that the reliability of the entire electronic control device 100 is greatly impaired.

  Therefore, in the present embodiment, the overlapping region 21 </ b> A of the through hole 21 is formed so as to include a portion directly below the brittle electronic component 5, that is, a region overlapping with at least a portion of the brittle electronic component 5. As a result, as shown in FIG. 9A, the sealing resin 9 sufficiently flows into the overlapping region 21A of the through hole 21 by the pressure during the transfer molding process. For this reason, the sealing resin 9 is sufficiently filled between the brittle electronic component 5 and the electronic circuit board 1 including the inside of the through hole 21, and an air layer is hardly formed.

  Also, if resin sealing by transfer molding process is used as in the present embodiment, the resin fills with a larger pressure than when resin sealing by immersion is used, so the air layer also moves at a higher pressure. As a result, voids are less likely to occur in the sealing resin 9.

  In the present embodiment in which a large amount of the sealing resin 9 can wrap around the back surface of the brittle electronic component 5, a wider area of the surface of the brittle electronic component 5 comes into contact with the sealing resin 9. Therefore, since the sealing resin 9 has a higher thermal conductivity than the air layer, in the present embodiment, the heat generated by the brittle electronic component 5 can be released from the sealing resin 9 to the outside more efficiently.

  Here, in general, the lifetime of the electronic component decreases as the temperature increases. In general, when the ambient temperature rises by 10 ° C., the lifetime of electronic components such as electrolytic capacitors is reduced to about ½. Furthermore, since the change in characteristics of electronic components increases with temperature, the output power and output voltage may become unstable if the ambient temperature rises. Therefore, efficiently dissipating the heat generated by the electronic component to the outside leads to a longer life of the electronic component and a stable operation.

  For this reason, the reliability of the whole electronic control apparatus 100 can be improved by using the structure of this Embodiment which can thermally radiate more efficiently from the through-hole 21.

  As described above, if the electronic control device 100 including the electronic circuit board 1 having the through-hole 21 that overlaps at least a part of the brittle electronic component 5 and surrounds the three directions around the electrode pad as in the present embodiment, Both the effects of suppressing the generation of voids and the suppression of damage to the electronic component 5 can be achieved, and the reliability of the electronic control device 100 can be improved. In addition, since the area where the electronic circuit board 1 is in close contact with the sealing resin 9 (including the inner peripheral surface of the through-hole 21) is increased, the heat dissipation efficiency of the brittle electronic component 5 can be further increased.

  Next, the adhesion between the electronic circuit board 1 and the sealing resin 9 is improved as the surface area of the region where both are in close contact with each other increases. In the present embodiment, the area of the through hole 21 in plan view is larger than that of the comparative example. For this reason, in the present embodiment, the area of the region where the electronic circuit board 1 and the sealing resin 9 are in close contact with each other through the through-hole 21 by the extent that the inner peripheral surface (inner wall surface) of the through-hole 21 is wide, It becomes larger than the area of the area | region where the electronic circuit board 1 and the sealing resin 9 contact | adhere through the through-hole 20 of a comparative example. Also from this viewpoint, it can be said that the adhesion between the electronic circuit board 1 and the sealing resin 9 is improved in this embodiment as compared with the comparative example.

  If the adhesion between the electronic circuit board 1 and the sealing resin 9 is improved, the sealing resin 9 from the surface of the electronic circuit board 1 is caused by thermal stress due to a temperature cycle or the like applied when the brittle electronic component 5 is driven. Peeling can be suppressed. From this point of view, it can be said that the present embodiment is more reliable than the comparative example.

  When the electronic circuit board 1 is formed of a general material such as epoxy glass, and the sealing resin 9 is formed of a general material such as an epoxy resin, it is generally easy to make them adhere to each other. is not. In addition, since the difference in coefficient of linear expansion between the electronic circuit board 1 and the sealing resin 9 is large, there is a possibility that both of them may be peeled off due to, for example, thermal stress caused by a temperature cycle applied at the time of driving. Is expensive. For this reason, the actual benefit by making it easy to stick both by enlarging the surface area which both stick together like this Embodiment is large.

  On the other hand, in the present embodiment, a part of the through hole 21 is an overlapping region 21A that overlaps the brittle electronic component 5, but the other part of the through hole 21 is a non-overlapping region 21B that does not overlap the brittle electronic component 5. Preferably there is. In this way, the pressure of the sealing resin 9 applied from the upper side to the lower side of the brittle electronic component 5 and the pressure of the sealing resin 9 applied from the lower side to the upper side of the brittle electronic component 5 can be easily balanced. Damage can be suppressed more reliably. Further, since the heat dissipation effect through the non-overlapping region 21B is higher than the heat dissipation effect through the overlapping region 21A, the presence of the non-overlapping region 21B further enhances the heat dissipation effect.

  Further, in the present embodiment, a pair of electrode pads 11 for connecting the brittle electronic component 5 are arranged on the main surface 1a of the electronic circuit board 1 so as to be arranged in a plurality along the axis l extending in one direction, The through hole 21 is formed so as to be symmetric with respect to the axis l in plan view. Thereby, the pressure of the sealing resin 9 applied from the upper side to the lower side of the brittle electronic component 5 and the pressure of the sealing resin 9 applied from the lower side to the upper side of the brittle electronic component 5 are easily balanced, and the brittle electronic component 5 is further damaged. It can be surely suppressed. In addition, the balance of heat radiation from the brittle electronic component 5 through the through hole 21 can be improved.

  Furthermore, in the present embodiment, when the brittle electronic component 5 is mounted by the reflow process using the solder 13, by supplying hot air through the through hole 21, it becomes easy to supply the hot air so as to directly hit the brittle electronic component 5. . Since the through hole 21 is formed near the region where the solder 13 is supplied, in particular, the component extending in the left-right direction in FIG. 2 is more efficient in supplying heat to the solder 13 than when the through hole 21 is not formed. Enhanced.

  Therefore, in the present embodiment, the brittle electronic component 5 can be easily mounted by the solder 13 even when the temperature of the hot air is low as compared with the case where the through hole 21 is not formed near the solder 13. That is, in the present embodiment, the temperature of the hot air can be lowered, so that components having low heat resistance can be mounted. Therefore, the types of components that can be mounted on the electronic circuit board 1 (including components with low heat resistance) are increased, and the range of options for electronic components mounted on the electronic control device 100 can be expanded.

  In the above description, the step of resin-sealing a general printed circuit board made of glass epoxy as the electronic circuit board 1 by the transfer molding method is described. However, even when a printed circuit board or the like to which a lead frame containing a copper element is bonded is used as the electronic circuit board 1, the same effect as described above can be obtained. In addition, heat dissipation and strength can be further enhanced by using a lead frame.

  Further, when the through hole 21 is formed around the electrode pad 11 connected to the normal electronic component 15 having a higher strength than the brittle electronic component 5 in the same manner as the brittle electronic component 5, (originally not easily damaged). Damage to the normal electronic component 15 can be more reliably suppressed.

(Embodiment 2)
Referring to FIG. 16, electrode pad 11 and through hole 21 in the first example of the present embodiment basically have the same planar form as electrode pad 11 and through hole 21 in the first embodiment shown in FIG. 2. Have. However, in the present embodiment, a circular hole 22 having a circular shape in plan view is formed at the end of the through hole 21 in plan view.

  The circular hole 22 is formed in each of two portions of the through-hole 21 extending in the left-right direction in FIG. 16, and is formed at both the left and right ends of the respective extending directions. Accordingly, a total of four circular holes 22 are formed in the through hole 21 of FIG. The circular hole 22 is formed so as to penetrate through the electronic circuit board 1 from the upper main surface 1a of the electronic circuit board 1 to the lower main surface 1b (in a direction crossing the main surface 1a), like the through hole 21. Further, it is a void region from which the material constituting the electronic circuit board 1 has been removed. The circular hole 22 is formed by pressing or drilling similarly to the through hole 21.

  Referring to FIG. 17, electrode pad 11 and through hole 21 in the first example of the present embodiment basically have the same planar form as electrode pad 11 and through hole 21 in the first embodiment shown in FIG. 2. Have. However, in FIG. 17, a circular hole 22 having a circular shape in plan view is formed at the center of the through hole 21 in plan view.

  In FIG. 17, a circular hole 22 is formed in a central portion of the through hole 21 that extends in the vertical direction of FIG. 17 in the extending direction. 17 is basically the same as the circular hole 22 in FIG. 16, and penetrates the electronic circuit board 1 from the upper main surface 1a to the lower main surface 1b of the electronic circuit board 1. Is formed.

  It is preferable that the circular hole 22 has a diameter larger than the width | variety regarding the direction which cross | intersects the direction where the through-hole 21 in which this is formed extends in planar view. Further, the circular hole 22 is preferably formed at a position where the center in plan view substantially overlaps the central portion in the width direction of the through hole 21.

  In FIGS. 16 and 17, the circular hole 22 is formed only in either the end portion or the central portion of the through hole 21 in plan view. However, although not shown, in the present embodiment, the circular holes 22 may be formed in both the end portion and the central portion of the through hole 21 in plan view.

  In addition, since the structure of the comparative example other than this is substantially the same as the structure of Embodiment 1, the same code | symbol is attached | subjected about the same element and the description is not repeated.

  Next, the function and effect of this embodiment will be described. In the present embodiment, in addition to the same functions and effects as those of the first embodiment, the following functions and effects can be achieved.

  In the present embodiment, circular holes 22 are formed at a part of the through hole 21, particularly at both ends in plan view as shown in FIG. Thereby, the stress concentration at both ends of the through hole 21 caused by the bending of the electronic circuit board 1 due to the pressure of the sealing resin 9 during the transfer molding process is alleviated. As a result, it is possible to reduce the possibility that the electronic circuit board 1 is cracked starting from the through hole 21.

  In the present embodiment, a circular hole 22 is formed at the center of the through-hole 21 in plan view, particularly as shown in FIG. As a result, a larger amount of the sealing resin 9 is formed through the through hole 21 including the circular hole 22 from the main surface 1b side (see FIG. 1), for example, below the electronic circuit board 1 in the transfer molding process. Can flow in. For this reason, as the force applied to the brittle electronic component 5, the pressure applied to the brittle electronic component 5 by the sealing resin 9 from the upper side to the lower side is balanced with the force from which the sealing resin 9 flows from the lower side to the upper side. It becomes easy. Therefore, the effect of suppressing breakage due to pressure from above the brittle electronic component 5 is enhanced.

  In the present embodiment, the total area of the inner peripheral surface of the through hole 21 and the circular hole 22 can be made larger than the area of the inner peripheral surface of the through hole 21 where the circular hole 22 is not formed. . For this reason, the contact area between the sealing resin 9 filling the inside of the through hole 21 and the circular hole 22 and the through hole 21 can be further increased, and the adhesion between them can be further improved. Further, since the adhesion between the electronic circuit board 1 and the sealing resin 9 is improved, the surface of the electronic circuit board 1 of the sealing resin 9 is caused by thermal stress due to a temperature cycle or the like applied when the brittle electronic component 5 is driven. Peeling can be suppressed. From this viewpoint, it can be said that the reliability is further improved in the present embodiment.

(Embodiment 3)
Referring to FIG. 18, electronic control device 200 in the present embodiment has basically the same configuration as electronic control device 100 in FIG. 1, and through hole 23 in the present embodiment basically has a configuration. It has the same planar shape as the through hole 21 of the first embodiment. However, the through hole 23 of the present embodiment is different from the through hole 21 of the first embodiment in that a copper plating film 41 is formed on the inner peripheral surface thereof. The copper plating film 41 is formed by electroless plating. The copper plating film 41 is preferably formed on substantially the entire inner peripheral surface of the through hole 23.

  Referring to FIGS. 19 and 20, the through hole 23 having the copper plating film 41 of the present embodiment also has an end portion and a central portion in plan view, similarly to the through hole 21 in FIGS. 16 and 17. The circular hole 22 may be formed in at least one (either or both).

  In addition, since the structure of the comparative example other than this is the same as the structure of Embodiment 1, 2, the same code | symbol is attached | subjected about the same element and the description is not repeated.

  Next, the function and effect of this embodiment will be described. In the present embodiment, in addition to the same functions and effects as those of Embodiments 1 and 2, the following functions and effects can be achieved.

  In the present embodiment, due to the presence of the copper plating film 41 on the inner peripheral surface of the through hole 23, the adhesion between the electronic circuit board 1 and the sealing resin 9 can be made higher than that in the first embodiment. This is because copper has better adhesion to the sealing resin 9 (epoxy resin) than, for example, epoxy glass constituting the electronic circuit board 1. Therefore, the effect of suppressing the peeling of the sealing resin 9 from the surface of the electronic circuit board 1 due to thermal stress due to a temperature cycle or the like applied when driving the brittle electronic component 5 is further enhanced than in the first embodiment. .

(Embodiment 4)
Referring to FIG. 21, electronic control device 300 in the present embodiment has basically the same configuration as electronic control device 200 in FIG. 18, and has through hole 23 in which copper plating film 41 is formed. Have. However, in the present embodiment, a heat generating electronic component 16 is mounted as another electronic component different from the brittle electronic component 5 on the main surface 1b on the lower side of the electronic circuit board 1, for example. Similarly to the brittle electronic component 5, the heat generating electronic component 16 is mounted so as to be electrically connected to the electrode pad 11 formed on the electronic circuit board 1 by the solder 13. The heat generating electronic component 16 is not a breakable component formed of a brittle material like the normal electronic component 15 described above. For example, an electronic device on which a semiconductor element having a larger heat generation than the brittle electronic component 5 is mounted. It is a part.

  The heat generating electronic component 16 is preferably mounted on the main surface opposite to the brittle electronic component 5. That is, for example, when the brittle electronic component 5 is mounted on the upper main surface 1 a of the electronic circuit board 1, the heat generating electronic component 16 may be mounted on the lower main surface 1 b of the electronic circuit board 1. preferable. The heat generating electronic component 16 is preferably placed at a position spaced apart from the through hole 23 directly below the brittle electronic component 5 with respect to the direction along the main surface of the electronic circuit board 1. In FIG. 21, the heat generating electronic component 16 is disposed slightly to the left of the through hole 23 directly below the brittle electronic component 5. In this way, propagation of heat generated by the heat generating electronic component 16 to surrounding components can be suppressed.

  A wiring pattern 42 is formed on the main surface 1 b in a region between the heat generating electronic component 16 and the copper plating film 41 of the through hole 23. The wiring pattern 42 is formed from a thin film of a generally known metal material such as copper or aluminum. The wiring pattern 42 is electrically connected in a region between the electrode pads 11 that connect the terminals of the heat generating electronic component 16 and the copper plating film 41 that covers the inner peripheral surface of the through hole 23 directly below the brittle electronic component 5, for example. It is formed so that it may connect. In other words, the copper plating film 41 in the through hole 23 is electrically connected to the heat generating electronic component 16 through the wiring pattern 42.

  In FIG. 21, a wiring pattern 42 is formed in the through hole 23 so as to be connected to the overlapping region 21 </ b> A (see FIG. 3) directly below the brittle electronic component 5, that is, the brittle electronic component 5. However, the present invention is not limited thereto, and the wiring pattern 42 may be formed so as to connect the heat generating electronic component 16 and the non-overlapping region 21 </ b> B (see FIG. 3) that does not overlap the brittle electronic component 5 in the through hole 23.

  In addition, since the structure of the comparative example other than this is substantially the same as the structure of Embodiment 3, the same code | symbol is attached | subjected about the same element and the description is not repeated.

  Next, the effect of this Embodiment is demonstrated using FIG. In the present embodiment, in addition to the same functions and effects as those of the third embodiment, the following functions and effects can be achieved.

  Referring to FIG. 22, electronic control device 300 of the present embodiment generates a large amount of heat generating electronic component 16 that generates a large amount of heat when driven. At this time, since heat moves from the higher temperature toward the lower temperature, the heat generation H of the heat generating electronic component 16 travels through the wiring pattern 42 and reaches the copper plating film 41 to which the wiring pattern 42 is connected. Heat is radiated from the through hole 23 in which the copper plating film 41 is formed.

  The wiring pattern 42 is formed of a metal material having higher thermal conductivity than air and a resin material such as copper. Therefore, if the wiring pattern 42 is connected to the heat generating electronic component 16, the heat generation H of the heat generating electronic component 16 is quickly radiated from the copper plating film 41 through the wiring pattern 42.

  For this reason, the heat generation H from the heat generating electronic component 16 having a large heat generation amount can be efficiently radiated, and the electronic control device 300 can be operated more stably. Therefore, the reliability of the electronic control device 300 can be improved.

  In addition, since it is not necessary to install a separate heat dissipation member or the like in order to dissipate the heat of the heat generating electronic component 16, the electronic control device 300 can be reduced in size and the manufacturing cost of the electronic control device 300 can be reduced. it can.

  Here, the inside of the through hole 23 to which the heat generation H of the heat generating electronic component 16 is transmitted is filled with sealing resin. However, heat is quickly transmitted to the inside of the through hole 23 so that at least the electronic circuit board 1 The possibility of heat generation H being trapped (insulated) inside is reduced. For this reason, the effect of heat dissipation by transferring heat H to the through hole 23 can be sufficiently exhibited.

(Embodiment 5)
In each of the above embodiments, the through holes 21 and 23 are formed so as to surround the electrode pad 11 from three directions in plan view. However, as described above, in order to suppress the breakage of the brittle electronic component 5 due to the deflection of the electronic circuit board 1 when pressure is applied from one direction above the electronic circuit board 1 during the transfer molding process, at least What is necessary is just to form so that the circumference | surroundings of the electrode pad 11 may be enclosed from two directions. Further, the shape of the through-hole in the plan view is not necessarily long.

  For example, referring to FIG. 23, in the first example of the present embodiment, through hole 24 formed around electrode pad 11 has a region extending in the left-right direction in FIG. It is formed in the area | region below it. However, a through-hole 24 is formed in a region sandwiched between the pair of electrode pads 11 so as to extend in the vertical direction in the figure as in the other embodiments. For this reason, the left electrode pad 11 in FIG. 23 is in a mode in which only the two directions of the upper side and the right side are surrounded by the through hole 24. Further, the electrode pad 11 on the right side in FIG. 23 is in a mode in which only the upper and left directions are surrounded by the through-hole 24. Therefore, the through hole 24 in FIG. 23 has a shape like a letter “T” in plan view.

  Referring to FIG. 24, in the second example of the present embodiment, the through hole 25 formed around the electrode pad 11 is different from the other embodiment in the region sandwiched between the pair of electrode pads 11. It is formed so as to extend in the vertical direction of the figure in the same manner as in FIG. In addition, the through hole 25 has a region extending in the left-right direction in FIG. 23 in the left side of the component extending in the vertical direction in the region above the electrode pad 11 and in the vertical direction in the region below the electrode pad 11. It is formed only on the right side of the extending component. For this reason, the electrode pad 11 on the left side of FIG. 24 is in a mode in which only the two directions of the upper side and the right side are surrounded by the through hole 24. Further, the electrode pad 11 on the right side in FIG. 23 is in a mode in which only the two directions of the lower side and the left side are surrounded by the through hole 24. For this reason, the through hole 24 of FIG. 23 has a shape as if two letters “L” partially overlap each other in plan view.

  Referring to FIG. 25, in the third example of the present embodiment, through hole 26 formed around electrode pad 11 has a curved shape as if it is a letter “C” in plan view. These are formed so as to come into contact with each other in a region sandwiched between two electrode pads 11 and to be back to back. In this example, the through hole 26 is equivalent to an aspect formed so as to surround the three directions around the electrode pad 11 as in the first embodiment, but the shape in plan view is different from that in the other embodiments. It is not a long shape like this form, but a curved shape.

  Referring to FIG. 26, in the fourth example of the present embodiment, through hole 27 formed around electrode pad 11 surrounds three directions around electrode pad 11 as in the other embodiments. Further, it is formed so as to partially surround the other one direction.

  In addition, in any of the through holes 24 to 27 in FIGS. 23 to 26, the copper plating film 41 (see FIG. 18) may be formed on the inner peripheral surface as in the other embodiments, or the plane thereof. A circular hole 22 (see FIGS. 16 and 17) may be formed in at least one of the end portion and the central portion as viewed.

  23 to 26 has an effect of helping to deform the electronic circuit board 1 so as to bend when pressure from above is applied. For this reason, the effect which suppresses the failure | damage of the brittle electronic component 5 is heightened compared with the case where it has the through-hole 20 (refer FIG. 10, 11) of a comparative example at least.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  DESCRIPTION OF SYMBOLS 1 Electronic circuit board, 5 Brittle electronic component, 9 Sealing resin, 11 Electrode pad, 13 Solder, 15 Normal electronic component, 16 Heat generating electronic component, 21, 23, 24, 25 Through-hole, 21A Overlapping area, 21B Non-overlapping Area, 22 circular hole, 31 transfer mold die, 31a space area, 33 plunger, 35 sealing material tablet, 41 copper plating film, 42 wiring pattern, 100, 200, 300, 900 Electronic control device.

Claims (9)

A substrate,
Electronic components mounted on the main surface of the substrate;
A sealing resin supplied by a transfer molding method for sealing the substrate and the electronic component;
The substrate has a through-hole penetrating the substrate so as to extend in a direction intersecting the main surface so as to overlap at least a part of the electronic component,
The electronic control device, wherein the through hole is formed so as to surround an electrode pad formed on the main surface from at least two directions in order to make electrical connection with the electronic component.   The electronic control device according to claim 1, wherein the through hole is formed so as to surround the electrode pad from three directions.   3. The electronic control device according to claim 1, wherein a part of the through hole is formed in a region other than a region overlapping the electronic component in plan view. A plurality of the electrode pads are arranged along the axis extending in one direction on the main surface;
The electronic control device according to claim 1, wherein the through hole is formed so as to be symmetric with respect to the axis in plan view.   The electronic control device according to claim 1, wherein a copper plating film is formed on an inner peripheral surface of the through hole. Other electronic components different from the electronic components mounted on the main surface,
The electronic control device according to claim 5, further comprising a wiring pattern that electrically connects the other electronic component and the copper plating film of the through hole.   The circular hole which penetrates the said board | substrate in the direction which cross | intersects the said main surface, and has a circular shape in planar view is formed in at least any one of the edge part and center part in planar view of the said through-hole. The electronic control device according to any one of 6. Forming a through hole in the substrate;
Forming an electrode pad on the main surface of the substrate for electrical connection with an electronic component;
Mounting the electronic component on the main surface;
A step of resin-sealing the substrate on which the electronic component is mounted by a transfer molding method,
In the step of forming the electrode pad, the electrode pad is formed so as to be surrounded by the through hole from at least two directions,
In the step of mounting the electronic component, the electronic component is mounted so as to overlap at least a part of the through hole.   The method for manufacturing an electronic control device according to claim 8, wherein in the step of mounting the electronic component, the electronic component is bonded to the substrate by supplying hot air through the through hole.

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