JP6488658B2 - Electronic equipment - Google Patents

Description

  The present invention relates to an electronic device in which a circuit element and a heat dissipation member are mounted on a wiring board.

  Conventionally, there is a chip array module disclosed in Patent Document 1 as an example of an electronic device in which a circuit element and a heat dissipation member are mounted on a wiring board. In the chip array module, a semiconductor chip as a circuit element and a heat sink are mounted on a wiring board, and these are sealed by a sealing body. The semiconductor chip is mounted on a conductor pattern provided on the surface of the wiring board. Moreover, the heat sink is soldered to the extension part of the conductor pattern provided on the surface of the wiring board, and is soldered to the conductor pattern on the back surface of the wiring board. And the heat sink of the surface side and the heat sink of the back side are connected via the solder with which the inside of the through-hole formed in the wiring board was filled.

Japanese Patent No. 4666766

  However, in the chip array module, heat generated from the semiconductor chip is transmitted to the heat sink via the conductor pattern. This conductor pattern is provided on the surface of the wiring board. Therefore, the heat of the semiconductor chip is transmitted along the surface of the wiring board.

  Usually, a heating element such as a semiconductor chip has a characteristic of transferring heat in the thickness direction of the wiring board. However, since the chip array module transfers the heat of the semiconductor chip along the surface of the wiring substrate, there is a problem that heat dissipation is poor.

  The present invention has been made in view of the above problems, and an object thereof is to provide an electronic device that can improve heat dissipation.

In order to achieve the above object, the present invention provides:
A wiring board (10);
One surface side circuit element (21) mounted on one surface of the wiring board;
A heat dissipating member (41-43) mounted on the opposite side of one side of the wiring board;
Provided on the opposite surface, sealing the heat dissipation member and the connection portion between the wiring board and the heat dissipation member, and comprising a mold resin (70, 71) formed by molding, It is attached to an attached body (300) having a heat dissipation function as a main component,
The wiring board is provided from one surface to the opposite surface, and the through wiring portion (12) electrically connected to the one surface side circuit element is disposed to face the one surface side circuit element,
The heat dissipating member is disposed to face the through wiring portion and is electrically connected to the through wiring portion to form a part of a current path passing through the one-side circuit element.
Mold resin is attached to the body to be attached,
The heat radiating member is exposed from the mold resin (71) on the opposite side of the surface facing the wiring board,
The opposite surfaces of the mold resin (71) and the heat dissipating member are joined to the mounted body via an electrically insulating adhesive (210).

  Thus, according to the present invention, the through wiring portion is disposed to face the one-surface circuit element, and the heat dissipation member is disposed to face the through wiring portion. For this reason, this invention can radiate | emit the heat emitted from the one surface side circuit element in the thickness direction, and can improve heat dissipation. Moreover, since this invention uses the thermal radiation member as a part of current path which passes along the one surface side circuit element, it can reduce wiring resistance rather than using metal foil as a current path. Furthermore, since the connection part of a heat radiating member and a wiring board is covered with mold resin, this invention can improve the thermal-life of a connection part rather than the case where the connection part is exposed to air. In particular, in the present invention, by adopting the mold resin, the connection strength at the connection portion can be improved as compared with the case where the sealing resin formed by potting is adopted.

  The reference numerals in parentheses described in the claims and in this section indicate the correspondence with the specific means described in the embodiments described later as one aspect, and the technical scope of the invention is as follows. It is not limited.

It is a top view which shows schematic structure of the electronic device in embodiment. It is a back view which shows schematic structure of the electronic device in embodiment. It is sectional drawing which follows the III-III line of FIG. It is sectional drawing which shows the 1st process of the manufacturing method in embodiment. It is sectional drawing which shows the 2nd process of the manufacturing method in embodiment. It is sectional drawing which shows the 3rd process of the manufacturing method in embodiment. It is sectional drawing which shows the 4th process of the manufacturing method in embodiment. It is sectional drawing which shows the 5th process of the manufacturing method in embodiment. It is sectional drawing which shows the 6th process of the manufacturing method in embodiment. It is sectional drawing which shows the 7th process of the manufacturing method in embodiment. It is sectional drawing which shows the molding process of the electronic device in embodiment. 10 is a cross-sectional view illustrating a schematic configuration of an electronic device according to Modification 1. FIG. 10 is a cross-sectional view illustrating a schematic configuration of an electronic device according to Modification 2. FIG. 11 is a cross-sectional view showing a molding process of an electronic device in Modification 2.

  Hereinafter, a plurality of embodiments for carrying out the invention will be described with reference to the drawings. In each embodiment, portions corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals and redundant description may be omitted. In each embodiment, when only a part of the configuration is described, the other configurations described above can be applied to other portions of the configuration.

  In this embodiment, the electronic device 100 shown in FIGS. 1 to 3 is employed as an example. The electronic device 100 includes a high-current motor drive circuit, and can be applied to a drive circuit for a radiator fan or electric power steering. However, the present invention is not limited to this.

  Further, the electronic device 100 is attached to the housing 300 via the adhesive 200. In the electronic device 100, a mold resin 70 to be described later is fixed to the housing 300 via an adhesive 200. More specifically, in the electronic device 100, the surface opposite to the surface facing the wiring substrate 10 in the mold resin 70 is fixed to the housing 300 via the adhesive 200. The housing 300 is mainly composed of metal and has a heat dissipation function. The housing 300 is, for example, a housing for housing the electronic device 100, a motor fan in a radiator fan or electric power steering, and the like. In addition, the housing | casing 300 is corresponded to the to-be-attached body in a claim. Moreover, it is preferable that the adhesive 200 has a relatively high thermal conductivity such as heat radiation grease. However, the present invention is not limited to this. Further, the surface opposite to the surface facing the wiring substrate 10 in the mold resin 70 can also be referred to as the mounting surface of the mold resin 70.

  The electronic device 100 includes a wiring board 10, circuit elements 21 and 22, heat sinks 41 to 43, a mold resin 70, and the like. In addition, the electronic device 100 may include the connector 23 and the resin thickness management member 50. Furthermore, the electronic device 100 may include solder 30 for connecting the wiring board 10 and the circuit elements 21 and 22, and solder 60 for connecting the wiring board 10 and the heat radiation plates 41 to 43.

  The wiring substrate 10 is obtained by forming a pattern wiring 11 and a through wiring 12 made of a conductive member on an insulating resin base material. As the wiring board 10, for example, a so-called buildup board including a core layer and a buildup layer laminated on the core layer can be adopted. The wiring board 10 may be a so-called any layer board in which a core layer is not provided and a plurality of buildup layers are stacked. Thus, the wiring board 10 can be rephrased as a printed board. The wiring board 10 has a rectangular parallelepiped shape, for example. That is, the wiring board 10 has a rectangular shape on one surface and the opposite surface, and has four side surfaces provided continuously on the one surface and the opposite surface.

  The pattern wiring 11 is obtained by patterning a foil-like conductive member. The pattern wiring 11 is electrically connected to the through wiring 12. As will be described later, a part of the pattern wiring 11 is not electrically connected to the through wiring 12.

  The through wiring 12 corresponds to the through wiring portion in the claims, and is provided from one surface to the opposite surface. In other words, the through wiring 12 is provided through the resin base material in the thickness direction. The through wiring 12 includes, for example, an interlayer connection member such as a laser via or a blind via. Further, the through wiring 12 is provided in a straight line, for example.

  The through wiring 12 is provided at a position facing the circuit elements 21 and 22, and is electrically connected to the circuit elements 21 and 22. Further, the through wiring 12 is provided at a position facing the connector 23 and is electrically connected to the connector 23. In other words, the through wiring 12 is provided directly below the circuit elements 21 and 22 and the connector 23.

  The wiring board 10 is provided with lands on which the circuit elements 21 and 22 are mounted on one surface, and lands on which the heat sinks 41 to 43 are mounted on the opposite surface. This land is constituted by a part of the pattern wiring 11 and the through wiring 12. In addition, the pattern wiring 11 and the through wiring 12 can employ, for example, a main component of a metal such as copper.

  As shown in FIGS. 1 and 3, a power semiconductor element 21 as a circuit element, a large component 22, and a connector 23 are mounted on one surface of the wiring board 10. The power semiconductor element 21, the large component 22, and the connector 23 are electronic components that form part of a large current motor drive circuit. For this reason, a large current is passed through the power semiconductor element 21, the large component 22, and the connector 23. The large current is, for example, 30 A or more.

  The power semiconductor element 21 corresponds to the one-side circuit element in the claims. The power semiconductor element 21 is a switching element that performs energization and interruption of a large current. For example, a MOSFET or the like can be employed. The power semiconductor element 21 generates heat when it operates, and can also be referred to as a heating element. In the present embodiment, as shown in FIG. 1, an example in which three power semiconductor elements 21 are mounted on the wiring board 10 is employed.

The power semiconductor element 21 is provided with a back electrode on the mounting surface with respect to the wiring substrate 10, and with a terminal 21 a protruding from a side wall or the like. In the power semiconductor element 21, the back electrode and the terminal 21 a are mounted on one surface of the wiring substrate 10 via the solder 30. The solder 30 is electrically connected to the pattern wiring 11 and the through wiring 12. That is, the power semiconductor element 21 is electrically and mechanically connected to the wiring board 10 by the solder 30. Thus, the power semiconductor element 21 is a surface- mounted circuit element.

  Further, the through wiring 12 connected to the power semiconductor element 21 via the solder 30 is disposed opposite to the power semiconductor element 21 as shown in FIG. That is, the through wiring 12 is provided at a position facing the back electrode and the terminal 21a. In other words, the through wiring 12 is provided directly under the back electrode and the terminal 21a.

  The large component 22 is a circuit element that forms part of the drive circuit. The large component 22 can employ, for example, a noise prevention element such as an aluminum electrolytic capacitor or a coil. That is, the large component 22 is a large circuit element different from the power semiconductor element 21. In the present embodiment, as shown in FIG. 1, an example in which three large components 22 are mounted on the wiring board 10 is employed.

Further, the large component 22 is provided with two electrodes 22 a on the mounting surface with respect to the wiring board 10. In the large component 22, the electrode 22 a is mounted on one surface of the wiring board 10 via the solder 30. That is, the large component 22 is electrically and mechanically connected to the wiring board 10 by the solder 30. Thus, the large component 22 is a surface- mounted circuit element.

  Furthermore, the through wiring 12 connected to the large component 22 via the solder 30 is disposed opposite to the large component 22 as shown in FIG. That is, the through wiring 12 is provided at a position facing the electrode 22 a of the large component 22. In other words, the through wiring 12 is provided directly below the electrode 22a.

The connector 23 is provided for electrical connection between the electronic device 100 and an external device provided outside the electronic device 100. For example, the connector 23 is electrically connected to a motor that is a driving target of the electronic device 100. The connector 23 is provided with a plurality of terminals 23a on a resin cover. In the connector 23, the terminals 23 a are mounted on one surface of the wiring board 10 via the solder 30. That is, the connector 23 has the terminals 23 a electrically and mechanically connected to the wiring board 10 by the solder 30. Thus, the connector 23 is a surface mount type connector.

  Further, the through wiring 12 connected to the connector 23 via the solder 30 is disposed so as to face the connector 23 as shown in FIG. That is, the through wiring 12 is provided at a position facing the terminal 23 a of the connector 23. In other words, the through wiring 12 is provided directly below the terminal 23a.

  As shown in FIGS. 2 and 3, heat sinks 41 to 43 and a resin thickness management member 50 are mounted on the opposite surface of the wiring board 10 via solder 60. Further, as shown in FIG. 2, a back surface element 24 is mounted on the opposite surface of the wiring board 10. In FIG. 2, in order to make the configuration of the back surface side of the electronic device 100 easier to understand, the illustration of the mold resin 70 is omitted and the housing 300 is illustrated by a two-dot chain line.

  The heat sinks 41 to 43 and the resin thickness management member 50 are sealed with a mold resin 70 as shown in FIG. The mold resin 70 integrally seals the connection portions between the heat radiation plates 41 to 43 and the wiring board 10 in addition to the heat radiation plates 41 to 43. A connection portion between the heat sinks 41 to 43 and the wiring board 10 includes the solder 60. In addition to the resin thickness management member 50, the mold resin 70 integrally seals the connection portion between the resin thickness management member 50 and the wiring board 10. The connecting portion between the resin thickness management member 50 and the wiring board 10 includes the solder 60. However, the tip of the resin thickness management member 50 is exposed from the mold resin 70. This tip is the end of the resin thickness management member 50 opposite to the wiring board 10 side. On the other hand, the heat radiation plates 41 to 43 are sealed with a mold resin 70 except for the portion where the solder 60 is connected.

The mold resin 70 is a thermosetting resin such as an epoxy resin. The mold resin 70 is preferably a material having a linear expansion coefficient close to that of the constituent material such as the solder 60 and the first heat radiation plate 41 and the constituent material such as the through wiring 12. For this reason, it is preferable that the mold resin 70 is made of a material having a linear expansion coefficient of 35 × 10 ⁻⁶ / ° C. or less. By doing so, the electronic device 100 can reduce the thermal stress applied to the solder 60. Furthermore, the electronic device 100 can improve heat dissipation by using a material having good thermal conductivity, for example, a material such as 1 W / mK or more.

  The heat sinks 41 to 43 are mainly composed of a metal such as copper, and have a function as a wiring through which a current flows in addition to a function as a heat dissipation member. For this reason, the heat sinks 41 to 43 are members that are sufficiently thicker than the pattern wiring 11. As the heat sinks 41 to 43, for example, a flat plate member or a block body can be adopted.

  The 1st heat sink 41 is provided in the position facing the terminal 23a and a back surface electrode. Further, as shown in FIG. 2, the first heat radiating plate 41 is disposed so as to face the most part of the power semiconductor element 21, that is, the part excluding the terminal 21 a of the power semiconductor element 21. Furthermore, in this embodiment, the three power semiconductor elements 21 are arranged to face each other. The first heat radiating plate 41 is electrically connected to the terminal 23 a through the through wiring 12 and the solders 30 and 60, and is electrically connected to the back electrode through the through wiring 12 and the solders 30 and 60. ing. That is, the first heat radiating plate 41 electrically connects the power semiconductor element 21 and the connector 23. In the present invention, a conductive adhesive can be employed instead of the solders 30 and 60.

  The 2nd heat sink 42 is provided in the position facing one electrode 22a and the terminal 21a. The second heat radiating plate 42 is electrically connected to one electrode 22 a through the through wiring 12 and the solders 30, 60, and is electrically connected to the terminal 21 a through the through wiring 12 and the solders 30, 60. It is connected. That is, the second heat radiating plate 42 electrically connects the power semiconductor element 21 and the large component 22.

  The third heat sink 43 is provided at a position facing the other electrode 22a. The third heat radiating plate 43 is electrically connected to the other electrode 22 a through the through wiring 12 and the solders 30 and 60.

  Thus, the power semiconductor element 21, the large component 22, and the connector 23 are connected via the through wiring 12, the heat sinks 41 to 43, and the like. Therefore, a large current flows through the electronic device 100 as indicated by a two-dot chain line in FIG. That is, the current path includes the terminal 23a, the wiring board 10, the first heat sink 41, the wiring board 10, the power semiconductor element 21, the wiring board 10, the second heat sink 42, the wiring board 10, the large component 22, the wiring board 10, A large current flows in the order of the third heat sink 43. Thus, the current path can be said to be a labyrinth. That is, it can be said that the electronic device 100 uses the wiring substrate 10 and the heat sinks 41 to 43 as power wiring through which a large current flows. Moreover, since the heat sinks 41-43 also serve as a part of wiring, they naturally have an area larger than that of the power semiconductor element 21. Here, the area is the area of the surface facing the wiring board 10. For this reason, the heat sinks 41-43 have the effect of thermally diffusing the heat transmitted to itself. That is, since the electronic device 100 has the heat sinks 41 to 43, the heat dissipation can be improved. Furthermore, since the heat sinks 41 to 43 are flat members or block bodies as described above, the wiring resistance can be reduced as compared with the foil-like pattern wiring 11 and the like.

  In the electronic device 100, the power semiconductor element 21 is connected to the first heat radiating plate 41 through the through wiring 12 or the like, so that the heat generated from the power semiconductor element 21 can be radiated from the first heat radiating plate 41. In this way, the electronic device 100 can transfer the heat generated from the power semiconductor element 21 in the direction directly below the power semiconductor element 21, that is, in the thickness direction of the wiring board 10.

  Note that the wiring board 10 can reduce the wiring resistance and thermal resistance by increasing the volume of the through wiring 12. That is, the wiring board 10 can reduce the wiring resistance and the thermal resistance by increasing the occupation ratio of the through wiring 12 in the facing region of the power semiconductor element 21.

  The resin thickness management member 50 is mounted on the wiring board 10 via the solder 60. The solder 60 that joins the resin thickness management member 50 and the wiring board 10 is mechanically connected to the pattern wiring 11 of the wiring board 10. However, the pattern wiring 11 is electrically insulated from the pattern wiring 11 that is electrically connected to the power semiconductor element 21 and the like. That is, the pattern wiring 11 is not included in the current path.

  The resin thickness management member 50 is a member for defining the thickness of the mold resin 70 on the heat sinks 41 to 43. “On the heat sinks 41 to 43” indicates the surface opposite to the surface of the heat sinks 41 to 43 facing the wiring board 10. The resin thickness management member 50 is defined to have a thickness that can ensure the insulating properties of the heat sinks 41 to 43 while maintaining the heat dissipation by the heat sinks 41 to 43. Therefore, it is preferable that the mold resin 70 formed on the heat radiating plates 41 to 43 is as thin as possible as long as the insulating properties of the heat radiating plates 41 to 43 can be secured. In addition, it can be said that the surface opposite to the surface facing the wiring board 10 in the heat radiation plates 41 to 43 is a heat radiation surface. Therefore, it can be said that the resin thickness management member 50 prescribes | regulates the space | interval of the virtual plane in alignment with the thermal radiation surface, and the virtual plane in alignment with the mounting surface of the mold resin 70. FIG.

  The resin thickness management member 50 is a member thicker than the heat sinks 41 to 43. The resin thickness management member 50 and the heat sinks 41 to 43 are mounted on the wiring board 10 via the solder 60. Therefore, the resin thickness management member 50 is a member thicker than the heat radiation plates 41 to 43 by the thickness of the mold resin 70 formed on the heat radiation plates 41 to 43. In addition, the resin thickness management member 50 is mounted on the wiring board 10, and the heat sinks 41 to 43 mounted on the wiring board 10 are equivalent to the thickness of the mold resin 70 formed on the heat sinks 41 to 43. What is necessary is just to protrude rather than.

  As will be described later, the resin thickness management member 50 manages the thickness of the mold resin 70 formed on the heat radiation plates 41 to 43 because the tip contacts the lower mold when the mold resin 70 is molded. it can. Therefore, the thickness of the mold resin 70 equivalent to the difference in thickness between the heat dissipation plates 41 to 43 and the resin thickness management member 50 is ensured on the heat dissipation plates 41 to 43. The thickness of the mold resin 70 on the heat sinks 41 to 43 can be set to 0.5 mm or less, for example. Thus, since the electronic device 100 can manage the thickness of the mold resin 70 on the heat radiation plates 41 to 43, the thermal coupling state with the housing 300 can be improved.

  In the present embodiment, the resin thickness management member 50 mounted on the wiring board 10 via the solder 60 is employed. That is, in this embodiment, the resin thickness management member 50 mainly composed of metal is employed. However, the present invention is not limited to this. The resin thickness management member 50 only needs to be able to regulate the thickness of the mold resin 70 on the heat radiation plates 41 to 43, and the material, shape, position where the resin is disposed, and the like are not particularly limited. In the present invention, the resin thickness management member 50 may not be provided.

  The back surface element 24 is a circuit element forming a part of the drive circuit, and corresponds to the opposite surface side circuit element in the claims. The back element 24 is, for example, a chip capacitor. The back surface element 24 is sealed with a mold resin 70 together with the heat radiating plates 41 to 43. In the present invention, the back surface element 24 may not be provided.

  Here, a method for manufacturing the electronic device 100 will be described with reference to FIGS. 4 to 11 are cross-sectional views showing the manufacturing process of the electronic device 100, and show a cut surface corresponding to FIG.

  In the first step, a wiring board 10 is prepared as shown in FIG. That is, in the first step, the wiring board 10 in which the pattern wiring 11 and the through wiring 12 are formed on the resin base material is prepared. In the second step, as shown in FIG. 5, solder 60 is formed on the back surface of the wiring board 10 by, for example, printing. Then, in a 3rd process, as shown in FIG. 6, the heat sinks 41-43 and the resin thickness management member 50 are mounted in the other surface of the wiring board 10. As shown in FIG. In this third step, the heat radiation plates 41 to 43 and the resin thickness management member 50 are arranged on the solder 60, and the heat radiation plates 41 to 43 and the resin thickness management member 50 are collectively mounted on the wiring board 10 by solder reflow. In the third step, in addition to the heat radiation plates 41 to 43 and the resin thickness management member 50, the back surface element 24 can also be packaged.

  In the fourth step, a mold resin 70 is formed on the back surface of the wiring board 10 as shown in FIG. The mold resin 70 can be formed by molding. That is, the fourth step can be rephrased as a molding step. Here, compression molding is employed as an example. In the molding process, as shown in FIG. 11, the mold resin 70 is formed using a mold including an upper mold 410 and a lower fixed mold 420 and a working lower mold 430 corresponding to the upper mold 410. The upper mold 410 and the lower mold can be relatively moved closer or farther away, for example, when the lower mold is raised or lowered.

  The upper mold 410 has a flat surface to which the wiring board 10 is fixed. The upper mold 410 is disposed in parallel with the ground, for example. The upper mold 410 has a flat surface on the ground side. The wiring substrate 10 is fixed to the flat surface with one surface facing the flat surface of the upper mold 410. The wiring board 10 is fixed to the upper mold 410 by, for example, a vacuum clamp or a mechanical clamp. However, the method for fixing the wiring board 10 to the upper mold 410 is not particularly limited. In the following description, the direction of gravity is set downward and the direction opposite to the direction of gravity is set upward.

  The lower mold is disposed on the lower side of the upper mold 410 so as to face the upper mold 410. The fixed lower mold 420 is provided with a hole surrounded by an annular wall surface. When the molding resin 70 is molded, the fixed lower mold 420 comes into close contact with the opposite surface of the wiring board 10.

  An operation lower mold 430 is arranged in the hole of the fixed lower mold 420 so as to be movable upward and downward along the hole. That is, the operating lower mold 430 is configured to be movable upward and downward within the range of the lowermost position and the uppermost position within the hole of the fixed lower mold 420.

  In the lower mold, a concave cavity in which the constituent material of the mold resin 70 is disposed is formed by the wall surface of the fixed lower mold 420 and the upper surface of the operating lower mold 430. That is, the upper surface of the lower working mold 430 becomes the bottom surface of the cavity. The upper surface of the lower working mold 430 is a flat surface. The constituent material of the mold resin 70 is, for example, a granular resin material.

  In the molding process, as shown in FIG. 11, the wiring substrate 10 is sandwiched between the upper mold 410 and the fixed lower mold 420. At this time, the constituent material of the mold resin 70 is disposed in the cavity. In the molding process, the lower working mold 430 is raised in the arrow direction until the upper surface of the lower working mold 430 contacts the resin thickness management member 50 in this state. The resin thickness management member 50 is taller than the heat sinks 41 to 43, and the upper surface of the operating lower mold 430 is a flat surface. Therefore, the heat sinks 41 to 43 are not exposed from the mold resin 70. That is, the electronic device 100 can manage the thickness of the mold resin 70 on the heat sinks 41 to 43 by the height of the resin thickness management member 50.

  Further, in the molding process, the wiring board 10 is pressed by the resin thickness management member 50. That is, the wiring board 10 is sandwiched between the upper mold 410 and the resin thickness management member 50. For this reason, in the molding process, even when the wiring board 10 is warped before the molding process, the warping of the wiring board 10 can be corrected.

  After the molding process, the fifth process shown in FIG. 8 is performed. In the fifth step, the solder 30 is formed on one surface of the wiring substrate 10 by, for example, printing. Thereafter, in the sixth step, as shown in FIG. 9, the power semiconductor element 21, the large component 22, and the connector 23 are mounted on one surface of the wiring board 10. In the sixth step, the power semiconductor element 21, the large component 22, and the connector 23 are disposed on the solder 30. At this time, the terminal 21 a, the back electrode, the electrode 22 a, and the terminal 23 a are disposed on the solder 30. In the sixth step, the power semiconductor element 21, the large component 22, and the connector 23 are collectively mounted on the wiring board 10 by solder reflow. As described above, the electronic device 100 can mount the heat sinks 41 to 43, the power semiconductor element 21 and the like on the wiring board 10 by the solder reflow on the back surface side and the solder reflow on the one surface side. Easy to manufacture without need.

  In the seventh step, as shown in FIG. 10, the electronic device 100 is attached to the housing 300 with the adhesive 200. In the seventh step, for example, the adhesive 200 is applied to the mounting area of the electronic device 100 in the housing 300. Thereafter, in the seventh step, the electronic device 100 is placed on the adhesive 200 to be fixed to the electronic device 100 and the housing 300. In this way, the electronic device 100 is mounted on the housing 300.

  As described above, in the electronic device 100, for example, the through wiring 12 is disposed to face the power semiconductor element 21, and the first heat radiating plate 41 is disposed to face the through wiring 12. For this reason, the electronic device 100 can dissipate the heat generated from the power semiconductor element 21 in the thickness direction. That is, the electronic device 100 can transfer heat from the power semiconductor element 21 to a direction directly below the power semiconductor element 21. Therefore, the electronic device 100 can improve heat dissipation compared with the case where the heat generated from the power semiconductor element 21 is radiated in the plane direction of the wiring board 10. In the electronic device 100, the through wiring 12 and the first heat radiating plate 41 are connected via the solder 60, so that the through wiring 12 and the first heat radiating plate 41 can be tightly bonded, and the heat dissipation is further improved. it can.

  Since the electronic device 100 uses the first heat radiating plate 41 as a part of the current path passing through the power semiconductor element 21, the wiring resistance can be reduced as compared with the case where the metal foil is used as the current path. The wiring board 10 is a versatile board that can be manufactured without performing a special process. Therefore, the electronic device 100 can reduce the wiring resistance by mounting the first heat radiation plate 41 on the versatile wiring board 10. For this reason, the electronic device 100 can be expected to suppress the cost increase, rather than using a wiring board manufactured by a special process.

  In the electronic device 100, a mold resin 70 that seals the first heat radiating plate 41 and the like is mounted on the housing 300 via an adhesive 200. Therefore, the electronic device 100 can radiate the heat generated from the power semiconductor element 21 to the housing 300 via the first heat radiating plate 41. For this reason, the electronic device 100 can further improve heat dissipation. Moreover, since the heat sink 41-43 which is a part of electric current path is sealed with the mold resin 70, the electronic device 100 can electrically insulate the heat sink 41-43, improving heat dissipation. Note that the pattern wiring 11 and the through wiring 12 may generate heat when a large current flows. However, heat generated from the pattern wiring 11 and the through wiring 12 can be radiated to the housing 300 from the first heat radiation plate 41 and the like.

  Furthermore, since the electronic device 100 covers the connection part between the heat radiation plates 41 to 43 and the wiring substrate 10 with the mold resin 70, the thermal life of the connection part can be improved as compared with the case where the connection part is exposed to the air. . In particular, in the electronic device 100, by using the mold resin 70, the connection strength at the connection portion can be improved as compared with the case of using the sealing resin formed by potting.

  In addition, although it is desirable for the wiring board 10 and the 1st heat sink 41 to have the same linear expansion coefficient, since a material does not become the same at all, generally a difference arises in a linear expansion coefficient. That is, the wiring board 10 and the first heat radiation plate 41 have different linear expansion coefficients. For this reason, the difference in elongation between the wiring board 10 and the first heat radiation plate 41 increases according to the ambient temperature. The stress applied to the connection portion between the wiring board 10 and the first heat radiation plate 41 increases as the difference in elongation at the connection portion between the first heat radiation plate 41 and the wiring board 10 increases. The difference in elongation increases as the length of the first heat radiating plate increases and as the temperature difference between the ambient temperatures increases. If the solder 60 is not encapsulated by the mold resin 70, stress is applied due to the difference in elongation, and cracking may occur if cooling is repeated. Accordingly, in the electronic device 100, when the solder 60 is not sealed with the mold resin 70, the heat dissipation is deteriorated or the wiring resistance is increased. Further, in the electronic device 100, when the solder 60 is not sealed with the mold resin 70, the wiring substrate 10 is warped due to the difference in elongation, so that the insulation between the first heat radiating plate 41 and the housing 300 is performed. May not be able to be secured.

  However, since the electronic device 100 seals the connection portion between the first heat radiation plate 41 and the wiring substrate 10 with the mold resin 70, the connection strength at the connection portion can be ensured. That is, since the electronic device 100 seals the solder 60 with the mold resin 70, it is possible to suppress deterioration of heat dissipation and increase in wiring resistance. Insulating properties can be secured. The relationship between the wiring board 10 and the second heat radiating plate 42 or the third heat radiating plate 43 is the same.

  In the electronic device 100, the power semiconductor element 21, the large component 22, and the like and the heat sinks 41 to 43 are mounted on the wiring board 10. In the wiring board 10, the distance between the power semiconductor element 21 and the large component 22 can be narrower than a bus bar or a lead frame. For this reason, the electronic device 100 can make a physique smaller than the case where the power semiconductor element 21, the large sized component 22, etc. and the heat sinks 41-43 are mounted in a bus bar. Thus, since the electronic device 100 can be reduced in size, it is easy to attach to the motor housing or the like. In other words, the electronic device 100 has good attachment properties to the attached body.

  The preferred embodiments of the present invention have been described above. However, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention. Hereinafter, modifications 1 and 2 of the present invention will be described. The above-described embodiment and Modifications 1 and 2 can be implemented independently, but can also be implemented in appropriate combination. The present invention is not limited to the combinations shown in the embodiments, and can be implemented by various combinations.

(Modification 1)
The electronic device 110 according to the first modification will be described with reference to FIG. Here, it demonstrates centering on a different point from the above-mentioned embodiment, and attaches | subjects the same code | symbol to the same point and abbreviate | omits description. The electronic device 110 is different from the electronic device 100 in that the heat radiation plates 41 to 43 are exposed from the mold resin 71.

  In the electronic device 110, the heat radiation surfaces of the heat radiation plates 41 to 43 are exposed from the mold resin 71. Here, a mold resin 71 in which a hole is provided at a position facing the heat radiating surface is employed. Since the electronic device 110 is provided with the resin thickness management member 50, the heat dissipation surface does not reach the mounting surface of the mold resin 71. For this reason, even if the electronic apparatus 110 is a case where it is arrange | positioned in the housing | casing 300 without the adhesive agent 210, for example, the heat sinks 41-43 do not contact the housing | casing 300. FIG.

  In the electronic device 110, the mounting surface of the mold resin 71 and the heat radiating surfaces of the heat radiating plates 41 to 43 are joined to the housing 300 via the adhesive 210. That is, since the electronic device 110 has a hole in the mold resin 71, the adhesive 210 comes into contact with the heat sinks 41 to 43. This adhesive 210 is electrically insulating and has a thermal conductivity better than that of the mold resin 70.

  The electronic device 110 can achieve the same effect as the electronic device 100. In addition, the adhesive 210 has better thermal conductivity than the mold resin 71. Further, in the electronic device 110, the heat radiation surfaces of the heat radiation plates 41 to 43 are joined to the housing 300 by the adhesive 210 without using the mold resin 71. For this reason, the electronic device 110 can improve heat dissipation more than the electronic device 100.

  In the electronic device 110, when the convex portion for providing the hole of the mold resin 71 is provided on the upper surface of the operating lower mold 430, the resin thickness management member 50 may not be provided. Further, in the electronic device 110, the resin thickness management member 50 may not be provided, and the heat radiation surfaces of the heat radiation plates 41 to 43 may be flush with the mounting surface of the mold resin 71. In this case, the electronic device 110 can electrically insulate the heat sinks 41 to 43 and the housing by the electrically insulating adhesive 210.

(Modification 2)
The electronic device 120 according to the second modification will be described with reference to FIGS. Here, it demonstrates centering on a different point from the above-mentioned embodiment, and attaches | subjects the same code | symbol to the same point and abbreviate | omits description. The electronic device 120 is different from the electronic device 100 in the configuration of the resin thickness management member 51.

  The resin thickness management member 51 defines the thickness of the mold resin 70 so that the heat radiation plates 41 to 43 are not exposed from the mold resin 70. More specifically, the resin thickness management member 51 can secure the insulating properties of the heat sinks 41 to 43 while maintaining the heat dissipation by the heat sinks 41 to 43 with respect to the thickness of the mold resin 70 on the heat sinks 41 to 43. Stipulate.

  The resin thickness management member 51 is formed of an insulator. Moreover, the resin thickness management member 51 is provided on the heat radiation surface of the heat radiation plates 41 to 43 as shown in FIG. The resin thickness management member 51 only needs to be provided on at least one heat radiating surface of the heat radiating plates 41 to 43. Further, the resin thickness management member 51 has a thickness equivalent to the thickness of the mold resin 70 on the heat radiation plates 41 to 43.

  When manufacturing the electronic device 120, as shown in FIG. 14, the resin thickness management member 51 is arranged on the upper surface of the operating lower mold 430. In this state, the electronic device 120 can be manufactured by performing a molding process in the same manner as in the above embodiment.

  The electronic device 120 can achieve the same effect as the electronic device 100. Furthermore, since the electronic device 120 is provided on the heat radiating surface of the heat radiating plates 41 to 43, the physique can be made smaller than the electronic device 100. That is, the electronic device 120 can be smaller in size in the planar direction than the electronic device 100.

  DESCRIPTION OF SYMBOLS 10 Wiring board, 11 Pattern wiring, 12 Through wiring, 21 Power semiconductor element, 21a terminal, 22 Large component, 22a terminal, 23 Connector, 23a terminal, 24 Back surface element, 30 Solder, 41-43 Heat sink, 50, 51 Resin Thickness management member, 60 solder, 70, 71 mold resin, 100-120 electronic device, 200, 210 adhesive, 300 housing, 410 upper mold, 420 fixed lower mold, 430 operating lower mold

Claims (8)

A wiring board (10);
One surface side circuit element (21) mounted on one surface of the wiring board;
A heat dissipating member (41-43) mounted on the opposite side of the one side of the wiring board;
Provided on the opposite surface, and the heat dissipation member, which seals the connecting portion between the heat dissipation member and the wiring substrate, a mold resin formed by molding (70, 71), the Equipped with a metal as a main component and attached to a mounted body (300) having a heat dissipation function,
The wiring board is provided from the one surface to the opposite surface, and a through wiring portion (12) electrically connected to the one-surface circuit element is disposed to face the one-surface circuit element,
The heat dissipating member is disposed to face the through wiring portion and is electrically connected to the through wiring portion to form a part of a current path passing through the one-surface circuit element,
The mold resin is attached to the attached body,
In the heat dissipation member, the opposite surface of the surface facing the wiring board is exposed from the mold resin (71),
The electronic device, wherein the opposite surfaces of the mold resin (71) and the heat radiating member are joined to the mounted body via an electrically insulating adhesive (210). A wiring board (10);
One surface side circuit element (21) mounted on one surface of the wiring board;
A heat dissipating member (41-43) mounted on the opposite side of the one side of the wiring board;
Provided on the opposite surface, and the heat dissipation member, which seals the connecting portion between the heat dissipation member and the wiring substrate, a mold resin formed by molding (70, 71), the Prepared,
The wiring board is provided from the one surface to the opposite surface, and a through wiring portion (12) electrically connected to the one-surface circuit element is disposed to face the one-surface circuit element,
The heat dissipating member is disposed to face the through wiring portion and is electrically connected to the through wiring portion to form a part of a current path passing through the one-surface circuit element,
On the opposite surface of the wiring board, a resin thickness management member (50) that defines the thickness of the mold resin is mounted so that the heat dissipation member is not exposed from the mold resin. apparatus. A wiring board (10);
One surface side circuit element (21) mounted on one surface of the wiring board;
A heat dissipating member (41-43) mounted on the opposite side of the one side of the wiring board;
Provided on the opposite surface, and the heat dissipation member, which seals the connecting portion between the heat dissipation member and the wiring substrate, a mold resin formed by molding (70, 71), the Prepared,
The wiring board is provided from the one surface to the opposite surface, and a through wiring portion (12) electrically connected to the one-surface circuit element is disposed to face the one-surface circuit element,
The heat dissipating member is disposed to face the through wiring portion and is electrically connected to the through wiring portion to form a part of a current path passing through the one-surface circuit element,
An insulating resin thickness management member (51) that defines the thickness of the mold resin is provided on the opposite surface of the heat dissipation member to the surface facing the wiring board so that the heat dissipation member is not exposed from the mold resin. An electronic device that is mounted. It is attached to a body (300) having a metal as a main component and having a heat dissipation function,
The molding resin, electronic device according to claim 2 or 3, characterized in that said attached to the attached body. In the heat dissipation member, the opposite surface of the surface facing the wiring board is exposed from the mold resin (71),
The electronic device according to claim 4 , wherein the opposite surfaces of the mold resin (71) and the heat radiating member are joined to the mounted body via an electrically insulating adhesive (210). apparatus. A wiring board (10);
One surface side circuit element (21) mounted on one surface of the wiring board;
Circuit components (22, 23) mounted on one surface of the wiring board, which are different from the one-surface circuit elements,
A heat dissipating member (41-43) mounted on the opposite side of the one side of the wiring board;
Provided on the opposite surface and sealing the heat radiating member and a connecting portion between the wiring board and the heat radiating member, and includes a mold resin ( 71) formed by molding. ,
The wiring board is provided from the one surface to the opposite surface, and a plurality of through-wiring portions (12) electrically connected to the one-surface circuit element and the circuit component include the one-surface circuit element and the one-side circuit element. It is placed opposite to the circuit parts,
The heat dissipating member is disposed to face the through wiring part, and is electrically connected to the through wiring part to form a part of a current path passing between the one-side circuit element and the circuit component ,
It is attached to a body (300) having a metal as a main component and having a heat dissipation function,
The mold resin is attached to the attached body,
The heat dissipating member has an opposite surface to the surface facing the wiring board exposed from the mold resin,
The electronic device , wherein the opposite surfaces of the mold resin and the heat radiating member are joined to the mounted body through an electrically insulating adhesive (210) . An opposite surface side circuit element (24) mounted on the opposite surface of the wiring board;
The said mold resin has sealed the said opposing surface side circuit element and the connection part of the said opposite surface side circuit element and the said wiring board, It is any one of Claim 1 thru | or 6 characterized by the above-mentioned. The electronic device described. The electronic device according to claim 1, wherein the heat radiating member is a block body containing a metal as a main component.

Images