JP2020129895A - Power conversion device - Google Patents

Abstract

To provide a power conversion device capable of radiating heat generated by a semiconductor element for power conversion and a conductor, while suppressing its configuration from being complex.SOLUTION: A power conversion device 100 comprises: a substrate 10; a semiconductor element 20 for power conversion mounted on a front surface 10a of the substrate 10; a bus bar 30 that is arranged on the front surface 10a of the substrate 10 separately from the substrate 10, and is electrically connected to the semiconductor element 20; and a heat radiation member 40 that is arranged so as to straddle the semiconductor element 20 and the bus bar 30, and radiates heat generated by the semiconductor element 20 and the heat generated by the bus bar 30.SELECTED DRAWING: Figure 1

Description

The present invention relates to a power converter, and more particularly to a power converter including a heat dissipation member for dissipating heat generated from a semiconductor element.

Conventionally, a heat dissipation member for dissipating heat generated from a semiconductor element has been known (for example, see Patent Document 1).

Patent Document 1 discloses an electronic component provided on the surface of a printed circuit board and a conductive portion provided on the surface of the printed circuit board. The thickness of the conductive portion is relatively small. Further, the electronic component is composed of a power module or the like, and heat is generated by using the electronic component. A heat sink including a plurality of heat radiation fins is provided on the surface of the electronic component. The heat generated by the electronic component is dissipated by the heat sink.

In addition, the conductive portion provided on the surface of the printed board is connected to the electronic component. Further, a plurality of conductive parts are provided. A wiring member is provided so as to extend over the plurality of conductive parts. The wiring member electrically connects the plurality of conductive parts. Further, the wiring member is formed by bending a sheet of metal. The wiring member includes a flat plate-shaped conductive connecting portion extending along a horizontal plane and a plurality of terminal portions extending from the conductive connecting portion. The plurality of terminal portions are connected to a conductive portion provided on the surface of the printed board. Moreover, the wiring member includes a heat dissipation portion. The heat radiating portion is provided so as to be orthogonal to the flat plate-like conductive connecting portion extending along the horizontal plane. Moreover, the heat dissipation part is provided so as to extend upward from the conductive connection part. Then, the heat generated by the current flowing through the conductive portion is radiated from the heat radiation portion of the wiring member.

JP, 2005-53306, A

However, in the conventional configuration as described in Patent Document 1, a heat sink for radiating the heat generated from the electronic component (power module) and a wiring member for radiating the heat generated by the current flowing through the conductive portion are used. Since the heat dissipating portion of the (conductor) is provided separately, there is a problem that the configuration becomes complicated.

The present invention has been made to solve the above problems, and one object of the present invention is to generate from a semiconductor element and a conductor for power conversion while suppressing a complicated configuration. An object of the present invention is to provide a power conversion device capable of radiating heat.

In order to achieve the above-mentioned object, a power conversion device according to one aspect of the present invention includes a substrate, a semiconductor element for power conversion mounted on the surface of the substrate, and a separate body from the substrate, which is disposed on the surface of the substrate. A conductor that is electrically connected to the semiconductor element, and a heat dissipation member that is disposed so as to straddle the semiconductor element and the conductor and that dissipates heat generated by the semiconductor element and heat generated by the conductor ..

As described above, the power converter according to one aspect of the present invention is arranged so as to straddle the semiconductor element and the conductor, and radiates heat generated by the semiconductor element and heat generated by the conductor. It has a member. As a result, the heat generated from the semiconductor element and the heat generated from the conductor are radiated by the heat radiation member arranged so as to extend over the semiconductor element and the conductor. As a result, unlike the case where a heat dissipation member that dissipates the heat generated from the semiconductor element and a heat dissipation member that dissipates the heat generated from the conductor are provided separately, the semiconductor for power conversion is suppressed while preventing the configuration from becoming complicated. The heat generated from the element and the conductor can be radiated.

In the power conversion device according to the above aspect, preferably, the conductor outputs a positive potential conductor that applies a positive potential to the semiconductor element, a negative potential conductor that applies a negative potential to the semiconductor element, and three-phase AC power. The heat dissipation member includes a plurality of output conductors and is arranged so as to straddle the semiconductor element, the positive potential conductor, the negative potential conductor, and the plurality of output conductors. According to this structure, unlike the case where the heat dissipation member is separately provided for the semiconductor element, the positive potential conductor, the negative potential conductor, and the plurality of output conductors, it is possible to further prevent the configuration from becoming complicated. can do.

In the power conversion device according to the above aspect, the height of the conductor with respect to the substrate is preferably equal to or less than the height of the semiconductor element with respect to the substrate. According to this structure, when the height of the conductor is the same as the height of the semiconductor element, the heat dissipation member extending over the conductor and the semiconductor element can be kept horizontal. In addition, when the height of the conductor is smaller than the height of the semiconductor element, a conductive paste or the like can be easily formed between the heat dissipation member and the conductor, so that the conductor (conductive paste) and the semiconductor element can be easily separated from each other. The radiating member can be kept horizontal.

In the power conversion device according to the above aspect, the substrate preferably includes a plurality of conductive layers and a plurality of insulating layers that are alternately stacked, and the thickness of the conductor is larger than the thickness of the conductive layer of the substrate. According to this structure, since the cross-sectional area of the conductor can be made relatively large, the electrical resistance of the conductor can be reduced. As a result, the heat generated from the conductor can be reduced.

In the power conversion device according to the above aspect, preferably, the semiconductor element includes a conductive member that is provided on the heat dissipation member side of the semiconductor element, and dissipates heat generated from the semiconductor element, and at least the semiconductor of the heat dissipation member. An insulating portion is provided on the element side and the conductor side to insulate the conductive member of the semiconductor element from the conductor. According to this structure, it is possible to prevent the semiconductor device and the conductor from being short-circuited by the insulating portion, and to prevent the configuration of the power conversion device from becoming complicated.

In this case, preferably, the heat dissipation member includes an insulating portion provided on the semiconductor element and conductor sides, and a conductive conductive heat dissipation member provided on the opposite side of the insulating portion from the semiconductor element and the conductor. According to this structure, the heat generated from the semiconductor element and the heat generated from the conductor by the conductive heat dissipating member having relatively general conductivity are suppressed while suppressing the short circuit between the semiconductor element and the conductor by the insulating portion. Can dissipate heat.

In the power conversion device according to the above aspect, preferably, the substrate includes a plurality of conductive layers and a plurality of insulating layers that are alternately laminated, is arranged on the back surface side of the substrate, and is a control unit for controlling the semiconductor element. Further, the semiconductor element and the control section are electrically connected to each other through a through hole via provided in a substrate on which a conductive layer and an insulating layer are laminated. According to this structure, since the semiconductor element is arranged on the front surface side of the substrate and the control section is arranged on the rear surface side of the substrate, the insulation distance of the control section with respect to the front surface side of the substrate to which a relatively high voltage is applied is set. Can be secured.

In the power conversion device according to the above aspect, preferably, the conductor includes a positive potential conductor that applies a positive potential to the semiconductor element and a negative potential conductor that applies a negative potential to the semiconductor element, and the substrates are alternately laminated. The positive potential conductor is electrically connected to the first conductive layer of the plurality of conductive layers via the first via, and the negative potential conductor is A second conductive layer different from the first conductive layer of the conductive layers is electrically connected via a second via, and the first conductive layer and the second conductive layer are separated from each other by the conductive layer and the insulating layer. Seen from the stacking direction, they overlap. According to this structure, since the first conductive layer and the second conductive layer are laminated (laminated), the inductance between the positive potential conductor and the negative potential conductor can be reduced. Accordingly, it is possible to reduce a switching surge when the semiconductor element includes a switching element or the like. Moreover, since the first conductive layer and the second conductive layer are sealed by the insulating layer, the insulating distance can be reduced, and the area of the first conductive layer and the area of the second conductive layer can be made relatively large. be able to.

In the power conversion device according to the above aspect, preferably, the control unit is disposed on the back surface side of the substrate and further includes a control unit for controlling the semiconductor element, and the substrate has a conductor conductive layer electrically connected to a conductor. Further comprising a control part conductive layer provided on the back surface side of the substrate and electrically connected to the control part, and controlling from the conductor conductive layer side between the conductor conductive layer and the control part conductive layer. A heat conduction shielding member for suppressing heat conduction to the part conductive layer side is provided. According to this structure, it is possible to prevent heat from being conducted to the control unit from the side of the conductive layer for a conductor, which has a relatively high temperature, and thus it is possible to suppress an adverse effect on the control unit due to the heat.

In this case, preferably, the heat conduction shielding member includes a plate-shaped first portion having conductivity and an insulating second portion that covers the front surface side and the back surface side of the first portion. According to this structure, the electromagnetic wave is shielded by the first portion having the plate-like conductivity, so that the adverse effect of the electromagnetic wave on the control unit can be suppressed.

According to the present invention, it is possible to provide a power conversion device capable of radiating heat generated from a power conversion semiconductor element and a conductor while suppressing a complicated structure.

It is the side view which looked at the power converter device by a 1st embodiment from the X1 direction side. It is the side view which looked at the power converter device by a 1st embodiment from the direction Y side. It is the perspective view which looked at the power converter by a 1st embodiment from the X2 direction side. FIG. 3 is an exploded perspective view of the power conversion device according to the first embodiment viewed from the X2 direction side. It is a figure which shows the surface of the semiconductor element of the power converter device by 1st Embodiment. It is a figure which shows the back surface of the semiconductor element of the power converter device by 1st Embodiment. It is a circuit diagram of the power converter according to the first embodiment. FIG. 3 is a cross-sectional view (schematic diagram) of the power converter according to the first embodiment. It is a figure which shows the 6th conductive layer of the board|substrate of the power converter device by 1st Embodiment. It is a figure which shows the 5th conductive layer of the board|substrate of the power converter device by 1st Embodiment. It is a figure which shows the 4th conductive layer of the board|substrate of the power converter device by 1st Embodiment. It is a figure which shows the 3rd conductive layer of the board|substrate of the power converter device by 1st Embodiment. It is a figure which shows the 2nd conductive layer of the board|substrate of the power converter device by 1st Embodiment. It is a figure which shows the 1st conductive layer of the board|substrate of the power converter device by 1st Embodiment. It is sectional drawing (schematic diagram) of the power converter device by 2nd Embodiment. It is sectional drawing (schematic diagram) of the semiconductor element of the power converter device by a modification.

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

[First Embodiment]
The configuration of the power conversion apparatus 100 according to the first embodiment will be described with reference to FIGS. 1 to 14.

(Structure of power converter)
As shown in FIGS. 1 to 4, the power conversion device 100 includes a substrate 10. The specific structure of the substrate 10 will be described later.

Moreover, as shown in FIGS. 1 and 2, the power conversion device 100 includes a semiconductor element 20 for power conversion. The semiconductor element 20 is composed of a switching element. Further, the semiconductor element 20 is configured to be mounted on the surface 10a (Z2 direction side) of the substrate 10. Specifically, as shown in FIGS. 5 and 6, the semiconductor element 20 is a surface-mounted semiconductor element 20. A source S, a drain D, and a gate D are provided on the front surface 20a side of the semiconductor element 20. Moreover, the source S, the drain D, and the gate D have a flat surface shape instead of a pin shape. The source S, drain D and gate D of the semiconductor element 20 are connected to the conductive layer 56 (see FIG. 9) of the substrate 10. The semiconductor element 20 is a QFN type (Quad For Non-Lead Package) having no pins.

Further, on the back surface 20b side of the semiconductor element 20, a thermal pad 20c for radiating heat generated from the semiconductor element 20 is provided. In plan view, the area of the thermal pad 20c is larger than the area of each of the source S, drain D, and gate D. The thermal pad 20c is an example of the "conductive member" in the claims.

Further, as shown in FIG. 7, a plurality of semiconductor elements 20 for power conversion are provided. The plurality of semiconductor elements 20 include a semiconductor element 20uu forming a U-phase upper arm and a semiconductor element 20ud forming a U-phase lower arm. In addition, the semiconductor element 20 includes a semiconductor element 20vu forming an upper arm of the V phase and a semiconductor element 20vd forming a lower arm of the V phase. Further, the semiconductor element 20 includes a semiconductor element 20wu forming an upper arm of the W phase and a semiconductor element 20wd forming a lower arm of the W phase.

Further, as shown in FIGS. 8 and 9, the power conversion device 100 includes a bus bar 30. The bus bar 30 is arranged on the surface 10 a of the substrate 10 separately from the substrate 10. The bus bar 30 is electrically connected to the semiconductor element 20. The bus bar 30 is made of copper, for example. As shown in FIG. 9, the bus bar 30 includes a positive potential bus bar 30p that applies a positive potential (P) to the semiconductor element 20 and a negative potential bus bar 30n that applies a negative potential (N) to the semiconductor element 20. .. Further, bus bar 30 includes three bus bars 30 (U-phase bus bar 30u, V-phase bus bar 30v and W-phase bus bar 30w) that output three-phase AC power. The positive potential bus bar 30p and the negative potential bus bar 30n are arranged side by side along the Y direction on the X2 direction side of the power converter 100. Further, U-phase bus bar 30u, V-phase bus bar 30v, and W-phase bus bar 30w are arranged side by side along the Y direction on the X1 direction side of power conversion device 100. The bus bar 30 is an example of the "conductor" in the claims. The U-phase bus bar 30u, the V-phase bus bar 30v, and the W-phase bus bar 30w are examples of the "output conductor" in the claims.

Here, in the first embodiment, as shown in FIG. 8, the power converter 100 includes a semiconductor element 20 and a bus bar 30 (a positive potential bus bar 30p, a negative potential bus bar 30n, a U-phase bus bar 30u, a V-phase bus bar 30v, and The heat dissipation member 40 is provided so as to straddle the W-phase bus bar 30w). The heat dissipation member 40 is configured to dissipate heat generated by the semiconductor element 20 and heat generated by the bus bar 30. Specifically, in a plan view, the heat dissipation member 40 is provided so as to cover substantially the entire substrate 10. Further, in a plan view, the heat dissipation member 40 has a substantially rectangular shape like the substrate 10.

Further, in the first embodiment, the heat dissipation member 40 includes the heat spreader 41 provided on the semiconductor element 20 and the bus bar 30 sides. The heat spreader 41 is configured to insulate the thermal pad 20c of the semiconductor element 20 from the bus bar 30. The heat spreader 41 has a flat plate shape. The heat spreader 41 is provided so as to cover substantially the entire substrate 10 in a plan view. Further, in a plan view, the heat spreader 41 has a substantially rectangular shape like the substrate 10. The heat dissipation member 40 also includes a heat sink 42. The heat sink 42 is provided on the opposite side of the heat spreader 41 from the semiconductor element 20 and the bus bar 30. The heat sink 42 is formed of a conductive metal (aluminum or the like). Further, the heat sink 42 includes a plurality of heat radiation fins 42a. The heat spreader 41 is an example of the "insulating portion" in the claims. The heat sink 42 is an example of the "conductive heat dissipation member" in the claims.

The heat spreader 41 is made of ceramics or the like. Specifically, the heat spreader 41 is made of aluminum nitride, ceramics containing a material having a relatively high thermal conductivity such as silicon nitride, or the like.

Further, in the first embodiment, as shown in FIG. 8, the height h2 of the bus bar 30 with respect to the substrate 10 is smaller than the height h1 of the semiconductor element 20 with respect to the substrate 10. A conductive paste 43 (or a conductive adhesive or the like) is arranged between the bus bar 30 and the heat dissipation member 40. As a result, the heat spreader 41 is arranged along the horizontal plane in the state where the flat plate-shaped heat spreader 41 is arranged on the semiconductor element 20 and the bus bar 30.

Further, in the first embodiment, the thickness t1 of the bus bar 30 is larger than the thickness t2 of the conductive layer 50 of the substrate 10 described later. For example, the thickness t1 of the bus bar 30 is about 0.6 mm. The thickness t2 of the conductive layer 50 of the substrate 10 is about 100 μm.

(Structure of substrate)
As shown in FIG. 8, the substrate 10 includes a plurality of conductive layers 50 (conductive layers 51 to 56) and a plurality of insulating layers 60 that are alternately stacked. Specifically, six conductive layers 50 are provided. The insulating layer 60 is provided between the six conductive layers 50. The conductive layer 50 is made of, for example, copper. The insulating layer 60 is made of resin, for example. The insulating layer 60 has a substantially rectangular shape in a plan view. The insulating layer 60 has a thickness of several hundreds μm, for example.

Further, as shown in FIG. 9, the semiconductor element 20 is electrically connected to the sixth conductive layer 56. The positive potential bus bar 30p, the negative potential bus bar 30n, the U-phase bus bar 30u, the V-phase bus bar 30v, and the W-phase bus bar 30w are also electrically connected to the sixth conductive layer 56. Specifically, the drain D of the semiconductor element 20uu forming the U-phase upper arm, the drain D of the semiconductor element 20vu forming the V-phase upper arm, and the positive potential bus bar 30p are electrically connected to the conductive layer 56a. It is connected to the. Further, the source S of the semiconductor element 20uu forming the U-phase upper arm, the drain D of the semiconductor element 20ud forming the U-phase lower arm, and the U-phase bus bar 30u are electrically connected to the conductive layer 56b. ing.

Further, the source S of the semiconductor element 20uu forming the lower arm of the U phase and the source S of the semiconductor element 20vd forming the lower arm of the V phase are electrically connected to the conductive layer 56c. The source S of the semiconductor element 20vu forming the upper arm of the V phase, the drain D of the semiconductor element 20vd forming the lower arm of the V phase, and the V phase bus bar 30v are electrically connected to the conductive layer 56d. ..

Further, the drain D of the semiconductor element 20wu forming the W-phase upper arm is electrically connected to the conductive layer 56e. The source S of the semiconductor element 20wu forming the W-phase upper arm, the drain D of the semiconductor element 20wd forming the W-phase lower arm, and the W-phase bus bar 30w are electrically connected to the conductive layer 56f. .. The source S of the semiconductor element 20wd that forms the lower arm of the W phase and the negative potential bus bar 30n are electrically connected to the conductive layer 56g.

Further, as shown in FIG. 10, the fifth conductive layer 55 includes a conductive layer 55a, a conductive layer 55b, and a conductive layer 55c.

Further, as shown in FIG. 11, the fourth conductive layer 54 includes a conductive layer 54a, a conductive layer 54b, and a conductive layer 54c.

Further, as shown in FIG. 12, the third conductive layer 53 includes a conductive layer 53a, a conductive layer 53b, and a conductive layer 53c.

Further, as shown in FIG. 13, the second conductive layer 52 includes a conductive layer 52a, a conductive layer 52b, and a conductive layer 52c as GND.

Here, in the first embodiment, as shown in FIG. 14, a control unit 70 for controlling the semiconductor element 20 is arranged on the back surface 10b side of the substrate 10. Specifically, the first conductive layer 51 of the substrate 10 includes a conductive layer 51 a, a conductive layer 51 b, and a conductive layer 51 c electrically connected to the control unit 70. The control unit 70 includes a gate driver or the like that drives the semiconductor element 20. A capacitor 81 and the like provided between the positive potential (P) and the negative potential (N) are also electrically connected to the first conductive layers 51a and 51b. A DC-DC converter 82 and the like are also electrically connected to the first conductive layer 51c.

Then, as shown in FIG. 8, the semiconductor element 20 and the control unit 70 are electrically connected to each other through the through-hole via 11 provided in the substrate 10 on which the conductive layer 50 and the insulating layer 60 are laminated. The through-hole via 11 is a conductive member that penetrates the substrate 10. The through hole via 11 is arranged in a through hole (through hole) provided in the substrate 10. The through-hole via 11 and the conductive layers 52 to 55 are insulated from each other.

Further, as shown in FIGS. 8 to 14, the positive potential bus bar 30p includes a sixth conductive layer 56a, a fifth conductive layer 55b, a fourth conductive layer 54a, a third conductive layer 53b, The conductive layer 52a of the second layer and the conductive layer 51a of the first layer are electrically connected via the through-hole via 12. The area of the fourth conductive layer 54a is relatively large, for example, larger than 1/2 of the area of the insulating layer 60.

Further, in the first embodiment, the positive potential bus bar 30p includes the sixth conductive layer 56e, the fifth conductive layer 55c, the fourth conductive layer 54a, and the third conductive layer via the inner via 13. It is electrically connected to the conductive layer 53c. The inner via 13 is an example of the “first via” in the claims.

The negative potential bus bar 30n includes a sixth conductive layer 56g, a fifth conductive layer 55a, a fourth conductive layer 54b, a third conductive layer 53a, a second conductive layer 52b, and It is electrically connected to the first conductive layer 51 b through the through hole via 15. The area of the fifth conductive layer 55a and the area of the third conductive layer 53a are relatively large, for example, larger than 1/2 of the area of the insulating layer 60.

Further, in the first embodiment, the negative potential bus bar 30n is electrically connected via the inner via 14 to the conductive layer 50 different from the conductive layer 50 to which the positive potential bus bar 30p is connected among the plurality of conductive layers 50. ing. Specifically, the negative potential bus bar 30n includes the sixth conductive layer 56c, the fifth conductive layer 55a, the fourth conductive layer 54c, and the third conductive layer 53a via the inner via 14. Is electrically connected to. The conductive layer 54 is an example of the "first conductive layer" in the claims. The conductive layers 53 and 55 are examples of the "second conductive layer" in the claims. The inner via 14 is an example of the “second via” in the claims.

In the first embodiment, the fifth conductive layer 55a electrically connected to the negative potential bus bar 30n, the fourth conductive layer 54a electrically connected to the positive potential bus bar 30p, and the negative potential. The third conductive layer 53a electrically connected to the bus bar 30n overlaps with each other when viewed from the direction (Z direction) in which the conductive layer 50 and the insulating layer 60 are stacked. That is, a laminated structure is formed by the fifth conductive layer 55a, the fourth conductive layer 54a, and the third conductive layer 53a.

(Effects of the first embodiment)
In the first embodiment, the following effects can be obtained.

In the first embodiment, as described above, the power conversion device 100 is arranged so as to straddle the semiconductor element 20 and the bus bar 30, and radiates heat generated by the semiconductor element 20 and heat generated by the bus bar 30. The heat dissipating member 40 is provided. As a result, the heat generated from the semiconductor element 20 and the heat generated from the bus bar 30 are radiated by the heat dissipation member 40 arranged so as to straddle the semiconductor element 20 and the bus bar 30. As a result, unlike the case where the heat dissipation member 40 that dissipates the heat generated from the semiconductor element 20 and the heat dissipation member 40 that dissipates the heat generated from the bus bar 30 are provided separately, power consumption is suppressed while suppressing the complexity of the configuration. The heat generated from the conversion semiconductor element 20 and the bus bar 30 can be radiated.

In addition, in the first embodiment, as described above, the heat dissipation member 40 includes the semiconductor element 20, the positive potential bus bar 30p, the negative potential bus bar 30n, and a plurality of output bus bars 30 (U-phase bus bar 30u, V-phase bus bar 30u, V phase). The bus bar 30v and the W-phase bus bar 30w) are arranged so as to straddle them. Thereby, unlike the case where the heat dissipation member 40 is provided separately for the semiconductor element 20, the positive potential bus bar 30p, the negative potential bus bar 30n, the U-phase bus bar 30u, the V-phase bus bar 30v, and the W-phase bus bar 30w. It is possible to further prevent the configuration from becoming complicated.

In the first embodiment, the height h2 of the bus bar 30 is smaller than the height h1 of the semiconductor element 20 as described above. Accordingly, by disposing the conductive paste 43 or the like between the heat dissipation member 40 and the bus bar 30, the heat dissipation member 40 extending between the bus bar 30 (the conductive paste 43) and the semiconductor element 20 can be easily horizontal. Can be kept.

Further, in the first embodiment, as described above, the thickness t1 of the bus bar 30 is larger than the thickness t2 of the conductive layer 50 of the substrate 10. As a result, the cross-sectional area of the bus bar 30 can be made relatively large, so that the electrical resistance of the bus bar 30 can be reduced. As a result, the heat generated from the bus bar 30 can be reduced.

In the first embodiment, as described above, the heat spreader 41 that insulates the thermal pad 20c of the semiconductor element 20 from the bus bar 30 is provided at least on the semiconductor element 20 side and the bus bar 30 side of the heat dissipation member 40. .. As a result, it is possible to prevent the semiconductor element 20 and the bus bar 30 from being short-circuited by the heat spreader 41 while suppressing the configuration of the power conversion device 100 from becoming complicated.

Further, in the first embodiment, as described above, the heat dissipation member 40 is provided with the heat spreader 41 provided on the semiconductor element 20 and the bus bar 30 side and the conductivity provided on the opposite side of the heat spreader 41 from the semiconductor element 20 and the bus bar 30. And a heat sink 42 having. As a result, heat generated by the semiconductor element 20 and heat generated by the bus bar 30 are radiated by the heat sink 42 having a relatively general conductivity while suppressing the short circuit between the semiconductor element 20 and the bus bar 30 by the heat spreader 41. can do.

Further, in the first embodiment, as described above, the semiconductor element 20 and the control unit 70 are electrically connected to each other via the through-hole via 11 provided in the substrate 10 on which the conductive layer 50 and the insulating layer 60 are laminated. Has been done. Accordingly, the semiconductor element 20 is arranged on the front surface 10a side of the substrate 10, and the control unit 70 is arranged on the rear surface 10b side of the substrate 10, so that the control unit for the front surface 10a side of the substrate 10 to which a relatively high voltage is applied. The insulation distance of 70 can be secured.

In addition, in the first embodiment, as described above, the positive potential bus bar 30p is electrically connected to the conductive layer 54a of the plurality of conductive layers 50 via the inner via 13, and the negative potential bus bar 30n includes a plurality of negative potential bus bars 30n. The conductive layers 55a and 53a, which are different from the conductive layer 54a of the conductive layer 50, are electrically connected via the inner via 14. The conductive layer 54a and the conductive layers 55a and 53a overlap each other when viewed from the direction in which the conductive layer 50 and the insulating layer 60 are stacked. As a result, the conductive layer 54a and the conductive layers 55a and 53a are laminated (laminated), so that the inductance between the positive potential bus bar 30p and the negative potential bus bar 30n can be reduced. As a result, it is possible to reduce the switching surge when the semiconductor element 20 includes a switching element or the like. In addition, since the conductive layer 54a, the conductive layer 55a, and the conductive layer 53a are sealed by the insulating layer 60, the insulating distance can be reduced and the areas of the conductive layer 54a, the conductive layer 55a, and the conductive layer 53a can be reduced. Can be relatively large.

[Second Embodiment]
The configuration of the power conversion device 200 according to the second embodiment will be described with reference to FIG. 15. In the second embodiment, a heat conduction shield member 201 is provided for suppressing heat conduction from the conductive layer 50 on the bus bar 30 side to the conductive layer 50 on the control unit 70 side.

As shown in FIG. 15, a control unit 70 for controlling the semiconductor element 20 is arranged on the back surface 10b side (first layer) of the substrate 10 as in the first embodiment. The semiconductor element 20 and the bus bar 30 are arranged on the front surface 10 a side of the substrate 10.

Here, in the second embodiment, the substrate 10 is provided with the heat conduction shielding member 201 for suppressing heat conduction from the conductive layer 50 on the bus bar 30 side to the conductive layer 50 on the control unit 70 side. There is. Specifically, the heat conduction shield member 201 is provided between the second conductive layer 52 and the third conductive layer 53. That is, the heat conduction shielding member 201 is provided between the third layer to the sixth layer, where a relatively high voltage is applied and the temperature is high, and the first layer and the second layer, where a relatively low voltage is applied and the temperature is relatively low. It is provided in. The third conductive layer 53, the fourth conductive layer 54, and the fifth conductive layer 55 are examples of the "conductive conductive layer" in the claims. Further, the first conductive layer 51 and the second conductive layer 52 are examples of the “control part conductive layer” in the claims.

Further, in the second embodiment, the heat conduction shielding member 201 includes a plate-shaped first portion 201a having conductivity and an insulating second portion 201b that covers the front surface side and the back surface side of the first portion 201a. .. The first portion 201a is made of a member having a relatively high thermal conductivity such as aluminum or copper. The second portion 201b is made of an insulating member such as glass epoxy resin or ceramics. Moreover, the thickness of the first portion 201 a is approximately the same as that of the bus bar 30. The thickness of the second portion 201b is several hundreds of μm. Further, the first portion 201a having conductivity is connected to a constant potential (for example, negative potential).

Further, the heat conduction shielding member 201, the second conductive layer 52, and the third conductive layer 53 are fixed to each other by being pressed against each other while applying heat.

(Effects of Second Embodiment)
In the second embodiment, the following effects can be obtained.

In the second embodiment, as described above, between the third conductive layer 53 and the second conductive layer 52, from the third conductive layer 53 side to the second conductive layer 52 side. A heat conduction shield member 201 is provided for suppressing heat conduction. With this, heat can be suppressed from being conducted to the control unit 70 from the side of the third conductive layer 53, which has a relatively high temperature, so that an adverse effect on the control unit 70 due to heat can be suppressed. ..

In addition, in the second embodiment, as described above, the heat conduction shield member 201 includes the first portion 201a having a plate-like conductivity and the insulating first portion 201a that covers the front surface side and the back surface 10b side of the first portion 201a. 2 portions 201b are included. Thereby, the electromagnetic wave is shielded by the first portion 201a having the plate-like conductivity, so that the adverse effect on the control unit 70 due to the electromagnetic wave can be suppressed.

[Modification]
It should be understood that the embodiments disclosed this time are exemplifications in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and further includes meanings equivalent to the scope of claims for patent and all modifications (modifications) within the scope.

For example, in the above-described first and second embodiments, the example in which the height of the bus bar with respect to the substrate is smaller than the height of the semiconductor element with respect to the substrate is shown, but the present invention is not limited to this. For example, the height of the bus bar with respect to the substrate and the height of the semiconductor element with respect to the substrate may be substantially the same. Thereby, the heat dissipation member can be kept horizontal without using a conductive paste or the like.

Further, in the above-described first and second embodiments, the example in which the substrate is formed by alternately stacking a plurality of conductive layers and a plurality of insulating layers has been shown, but the present invention is not limited to this. .. For example, it is possible to apply a configuration in which a heat dissipation member is arranged so as to straddle a semiconductor element and a bus bar on a substrate in which one conductive layer and one insulating layer are laminated.

Further, in the above-described first and second embodiments, the example in which the substrate is formed of six conductive layers has been shown, but the present invention is not limited to this. For example, the substrate may be formed of conductive layers other than 6 layers (4 layers or the like).

Moreover, in the said 1st and 2nd embodiment, although the heat dissipation member showed the example comprised by the heat spreader and the heat sink, this invention is not limited to this. For example, as in the modification shown in FIG. 16, as the “heat dissipation member” of the present invention, a heat dissipation member 340 formed of ceramics or the like may be used. As a result, the number of parts can be reduced.

Further, in the above-described first and second embodiments, the example in which the semiconductor element is the QFN type has been shown, but the present invention is not limited to this. For example, the semiconductor element may be a QFP type (Quad Flat Package).

Further, in the second embodiment, the example in which the heat conduction shielding member includes the plate-shaped first portion having conductivity and the second insulating portion is shown, but the present invention is not limited to this. For example, the heat-conducting shield member may be composed of a single member that has the expedition and can shield the conduction of heat.

Further, in the first and second embodiments, the example in which the bus bar is used as an example of the “conductor” of the present invention has been shown, but the present invention is not limited to this. For example, as an example of the "conductor" of the present invention, a copper foil pattern formed on a substrate (printed circuit board) may be used.

10 substrate 10a front surface 10b back surface 11 through-hole via 13 inner via (first via)
14 Innavia (2nd via)
20 semiconductor element 20c thermal pad (conductive member)
30 bus bar (conductor)
30p positive potential bus bar 30n negative potential bus bar 30u U-phase bus bar (conductor for output)
30v V phase bus bar (conductor for output)
30w W-phase bus bar (conductor for output)
40, 340 Heat dissipation member 41 Heat spreader (insulating part)
42 Heat sink (conductive heat dissipation member)
50 conductive layer 51, 52 conductive layer (control layer conductive layer)
53, 55 conductive layer (second conductive layer, conductive layer for conductor)
54 Conductive layer (first conductive layer, conductive layer for conductor)
56 Conductive layer (conductive layer for conductor)
60 Insulating layer 70 Control part 100, 200 Power converter 201 Heat conduction shielding member 201a 1st part 201b 2nd part

Claims (10)

Board,
A semiconductor element for power conversion mounted on the surface of the substrate,
A conductor arranged on the surface of the substrate separately from the substrate, and electrically connected to the semiconductor element,
A power conversion device comprising: a heat dissipation member that is disposed so as to straddle the semiconductor element and the conductor, and that dissipates heat generated by the semiconductor element and heat generated by the conductor. The conductor includes a positive potential conductor that applies a positive potential to the semiconductor element, a negative potential conductor that applies a negative potential to the semiconductor element, and a plurality of output conductors that output three-phase AC power,
The heat dissipation member, the semiconductor element, the positive potential conductor, the negative potential conductor,
The power conversion device according to claim 1, wherein the power conversion device is arranged so as to straddle the plurality of output conductors. The power conversion device according to claim 1, wherein a height of the conductor with respect to the substrate is equal to or lower than a height of the semiconductor element with respect to the substrate. The substrate includes a plurality of conductive layers and a plurality of insulating layers that are alternately stacked,
The power conversion device according to claim 1, wherein the conductor has a thickness greater than that of the conductive layer of the substrate. The semiconductor element includes a conductive member that is provided on the heat dissipation member side of the semiconductor element and that dissipates heat generated from the semiconductor element,
An insulating portion for insulating the conductive member of the semiconductor element from the conductor is provided at least on the semiconductor element side and the conductor side of the heat dissipation member. The power converter described. The heat dissipation member includes the insulating portion provided on the semiconductor element and the conductor side, and a conductive conductive heat dissipation member provided on the opposite side of the insulating portion from the semiconductor element and the conductor, Item 5. The power conversion device according to Item 5. The substrate includes a plurality of conductive layers and a plurality of insulating layers that are alternately stacked,
Disposed on the back side of the substrate, further comprising a control unit for controlling the semiconductor element,
7. The semiconductor element and the control unit are electrically connected to each other via a through-hole via provided in the substrate on which the conductive layer and the insulating layer are laminated. The power converter according to. The conductor includes a positive potential conductor that applies a positive potential to the semiconductor element, and a negative potential conductor that applies a negative potential to the semiconductor element,
The substrate includes a plurality of conductive layers and a plurality of insulating layers that are alternately stacked,
The positive potential conductor is electrically connected to a first conductive layer of the plurality of conductive layers via a first via,
The negative potential conductor is electrically connected to a second conductive layer different from the first conductive layer of the plurality of conductive layers via a second via,
The first conductive layer and the second conductive layer are overlapped with each other when viewed from the direction in which the conductive layer and the insulating layer are stacked. Power converter. Disposed on the back side of the substrate, further comprising a control unit for controlling the semiconductor element,
The substrate further includes a conductor conductive layer electrically connected to the conductor, and a control unit conductive layer provided on the back surface side of the substrate and electrically connected to the control unit,
Between the conductive layer for conductor and the conductive layer for control unit, a heat conduction shield member for suppressing heat conduction from the conductive layer side for conductor to the conductive layer side for control unit is provided. The power conversion device according to any one of claims 1 to 8. The power conversion device according to claim 9, wherein the heat conduction shielding member includes a first portion having a plate-like conductivity and an insulating second portion that covers a front surface side and a back surface side of the first portion. ..

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