JP7558866B2 - Power Conversion Equipment - Google Patents

Description

The present invention relates to a power conversion device.

In recent years, power conversion devices are being required to not only increase output, but also improve manufacturability. If a module is constructed in units of one phase's upper arm circuit or lower arm circuit, six modules are required to provide three phases. This makes it important to improve the manufacturability of power semiconductor modules. On the other hand, even if manufacturability is improved, if it leads to an increase in thermal resistance, it will hinder the increase in output of the power conversion device. Since in-vehicle power conversion devices are used in environments with greater temperature changes than industrial use, etc., there is a demand for power conversion devices that can maintain high reliability even in high-temperature environments. Patent Document 1 discloses a power conversion device having a first heat sink, a first substrate mounted on the main surface of the first heat sink, a first semiconductor element mounted on the main surface of the first substrate, a first electrode mounted on the main surface of the first heat sink or on the main surface of the first substrate, a plurality of first wire bonding wires arranged on the upper surface of the first semiconductor element and electrically connecting the first upper electrode of the first semiconductor element to the first electrode, a heat spreader in contact with the first upper electrode, a convex portion provided on one side of the heat spreader that passes between the first wire bonding wires and contacts or is close to the first upper electrode, and a concave portion close to the first wire bonding wire, and a second heat sink mounted on the other side of the heat spreader.

JP 2009-171732 A

The invention described in Patent Document 1 leaves room for improvement in manufacturability and heat dissipation.

A power conversion device according to a first aspect of the present invention comprises a semiconductor element, and a first substrate and a second substrate arranged opposite to each other, the first substrate having a first main surface facing the second substrate and a first sub-surface opposite to the first main surface, the second substrate having a second main surface facing the first substrate and a second sub-surface opposite to the second main surface, a first conductor exposed to the first sub-surface is embedded in the first substrate, and a second conductor exposed to the second sub-surface is embedded in the second substrate, the semiconductor element is disposed between the first conductor and the second conductor, the semiconductor element is electrically connected to the first conductor and the second conductor , the first conductor is exposed to both the first main surface and the first sub-surface, and the second conductor is exposed to both the second main surface and the second sub-surface, one or both of the first conductor and the second conductor form a recess, and the semiconductor element is housed in the recess .
A power conversion device according to a second aspect of the present invention comprises a semiconductor element, and a first substrate and a second substrate arranged opposite to each other, the first substrate having a first main surface facing the second substrate and a first sub-surface opposite to the first main surface, the second substrate having a second main surface facing the first substrate and a second sub-surface opposite to the second main surface, a first conductor exposed to the first sub-surface is embedded in the first substrate, and a second conductor exposed to the second sub-surface is embedded in the second substrate, the semiconductor element is disposed between the first conductor and the second conductor, the semiconductor element is electrically connected to the first conductor and the second conductor, the first substrate and the second substrate have a third conductor and a fourth conductor different from the first conductor and the second conductor, the third conductor and the fourth conductor are connected with a metal bonding material to connect the first substrate and the second substrate, and at least one of the third conductor and the fourth conductor has a second recess for accommodating the metal bonding material.
A power conversion device according to a third aspect of the present invention comprises a semiconductor element, and a first substrate and a second substrate arranged opposite to each other, the first substrate having a first main surface facing the second substrate and a first sub-surface opposite to the first main surface, the second substrate having a second main surface facing the first substrate and a second sub-surface opposite to the second main surface, a first conductor exposed at the first sub-surface is embedded in the first substrate and a second conductor exposed at the second sub-surface is embedded in the second substrate, the semiconductor element is disposed between the first conductor and the second conductor, the semiconductor element is electrically connected to the first conductor and the second conductor, the first substrate and the second substrate have fifth conductors and sixth conductors penetrating the respective substrates in addition to the first conductor and the second conductor, and another semiconductor element is connected to the fifth conductor and the sixth conductor in an inverted orientation relative to the semiconductor element.

The present invention provides a power conversion device with excellent manufacturability and heat dissipation properties.

1 is a schematic diagram of a power conversion device according to a first embodiment; 2 is a cross-sectional view taken along line II-II of FIG. 3 is a cross-sectional view taken along line III-III of FIG. IV-IV cross-sectional view of FIG. FIG. 13 is a diagram showing a part of a first power circuit unit in a first modified example. Schematic diagram of a power conversion device according to a second embodiment. 1 is a schematic diagram of a power conversion device according to a third embodiment. 1 is a schematic diagram of a power conversion device according to a fourth embodiment. IX-IX cross-sectional view of FIG.

-First embodiment-
A first embodiment of a power conversion device will be described below with reference to Figures 1 to 4. Hereinafter, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the following embodiment, and the technical idea of the present invention may be realized by combining other known components. Note that the same elements in each figure are denoted by the same reference numerals, and duplicated explanations will be omitted.

Figure 1 is a plan view showing an outline of the power conversion device 100, Figure 2 is a cross-sectional view taken along line II-II of Figure 1, Figure 3 is a cross-sectional view taken along line III-III of Figure 1, and Figure 4 is a cross-sectional view taken along line IV-IV of Figure 1. The power conversion device 100 is a power conversion device that converts DC power obtained from a battery or the like into AC power to be supplied to an electric motor, and constitutes an upper arm circuit and a lower arm circuit for one phase. The power conversion device 100 includes a first substrate 10, a second substrate 20, a first power circuit section 30 and a second power circuit section 40 formed by the first substrate 10 and the second substrate 20, a capacitor 80 that smoothes the voltage applied to the power conversion device 100, and a control circuit 90 that provides drive signals to the first power circuit section 30 and the second power circuit section 40, respectively.

2, the first substrate 10 has a first main surface 10P on the inside of the power conversion device 100 and a first sub-surface 10Q on the opposite side of the first main surface 10P. The second substrate 20 has a second main surface 20P on the inside of the power conversion device 100 and a second sub-surface 20Q on the opposite side of the second main surface 20P. That is, the first main surface 10P of the first substrate 10 and the second main surface 20P of the second substrate 20 are joined facing each other to form the power conversion device 100. In the following, as shown in the lower part of FIGS. 2 to 4, the direction in which the first substrate 10 and the second substrate 20 are arranged is referred to as the "first direction", and the direction perpendicular to the first direction is referred to as the "second direction".

The first board 10 and the second board 20 are mainly printed circuit boards. The first board 10 and the second board 20 have multiple conductor layers made of copper material, etc., and other parts are made of insulating materials such as glass epoxy resin. For convenience of illustration, in Figure 2 and other figures, the thickness of the conductor layers of the first board 10 and the second board 20 is shown to be about one-third of the thickness of the board, but in reality the conductor layers are about several tens of micrometers thick, which is a very small proportion of the thickness of the board. If a large current is passed through this conductor layer, the impedance is relatively large and the inductance also increases.

First, the first power circuit unit 30 will be described with reference to Figures 1 and 2. The first power circuit unit 30 includes an IGBT 50, a diode 54, a collector conductor 60, an emitter conductor 61, a gate conductor pattern 62, a cathode conductor 63, and an anode conductor 64. The IGBT 50 has a plate-shaped main electrode and a gate electrode 53 that controls the main current flowing through the main electrode. The main electrode is separated into upper and lower electrodes of the IGBT 50, with the collector electrode 51 provided on the lower surface and the emitter electrode 52 and gate electrode 53 provided on the upper surface. The diode 54 is plate-shaped, and from the perspective of Figure 2, a cathode electrode 55 is provided on the lower surface and an anode electrode 56 is provided on the upper surface.

Collector conductor 60, emitter conductor 61, gate conductor pattern 62, cathode conductor 63, and anode conductor 64 are composed of conductors, for example, copper material. Of these, at least collector conductor 60, emitter conductor 61, cathode conductor 63, and anode conductor 64, excluding gate conductor pattern 62, are not wiring patterns on a printed circuit board, but are lumps of conductive material with a thickness of several hundred micrometers or more and good thermal conductivity, for example, a copper lump. Since the conductor lump is thicker than the wiring pattern, the impedance is lower and the inductance is also smaller.

The collector conductor 60 and the cathode conductor 63 are embedded in the first substrate 10 and penetrate the first substrate 10. In other words, both the collector conductor 60 and the cathode conductor 63 penetrate from the first major surface 10P to the first minor surface 10Q.

The collector conductor 60 forms a recess 70 for accommodating the IGBT. The IGBT 50 is accommodated inside the recess 70 for accommodating the IGBT, and is electrically connected to the collector electrode 51 of the IGBT 50 via a metal bonding material 73 such as solder. The cathode conductor 63 forms a recess 71 for accommodating the diode. The diode 54 is accommodated inside the recess 71 for accommodating the diode, and is electrically connected to the cathode electrode 55 of the diode 54 via the metal bonding material 73. As a result, the first main surface 10P of the first substrate 10 becomes planar by mounting the IGBT 50 and the diode 54, and the connection to the second substrate 20 is facilitated, improving manufacturability.

In FIG. 2, the collector conductor 60 has an IGBT-accommodating recess 70, so that a portion of the collector conductor 60 is recessed from the first main surface 10P, but the end of the collector conductor 60 is flat and flush with the first main surface 10P. Similarly, the cathode conductor 63 has a diode-accommodating recess 71, so that a portion of the collector conductor 60 is recessed from the first main surface 10P, but the end of the cathode conductor 63 is flat and flush with the first main surface 10P.

As shown in FIG. 2, the emitter conductor 61 and the anode conductor 64 are embedded in the second substrate 20 and penetrate the second substrate 20. The second main surface 20P side of the emitter conductor 61 is in a flat state with no step with the second main surface 20P, that is, in a so-called flush state. The second main surface 20P side of the emitter conductor 61 is electrically connected to the emitter electrode 52 of the IGBT 50 via a metal bonding material 73. The second main surface 20P side of the anode conductor 64 is in a flat state with no step with the second main surface 20P, that is, in a so-called flush state. The second main surface 20P side of the anode conductor 64 is electrically connected to the anode electrode 56 of the diode 54 via the metal bonding material 73. In this way, the connection surfaces of the second substrate 20 connected to the IGBT 50 and the diode 54 are unified into a flat surface, thereby improving manufacturability.

The gate conductor pattern 62 is formed on the second substrate 20 and is electrically connected to the gate electrode 53 of the IGBT 50 via a metal bonding material 73. The gate conductor pattern 62 is connected to the upper surface of the second substrate 20 via a via 74. This connects all the electrodes of the IGBT 50 and the diode 54 to the conductor pattern on the first substrate 10 or the second substrate 20. As a result, compared to the conventional main circuit structure consisting of hundreds of wire bonds, multiple lead frames, and bus bars, the reduction in components improves manufacturability and enables cost reduction. Furthermore, the manufacturing process can be shortened by simplifying the bonding process to only the solder bonding process between the circuit substrate and the semiconductor element.

As shown in Figures 2 and 3, dummy conductors 65 are provided on the upper surface of the first substrate 10 and the lower surface of the second substrate 20. Note that in Figures 2 and 3, the dummy conductors 65 are shown on the left, center, and right sides of the figures, but for convenience of drawing, only the left side is labeled. The dummy conductor 65 is a mass of conductor, similar to the collector conductor 60 and emitter conductor 61.

In the dummy conductors 65 of each first substrate 10, a substrate bonding recess 72 for accommodating a metal bonding material 73 is formed surrounding the IGBT 50 and the diode 54. The first substrate 10 and the second substrate 20 are connected by connecting the dummy conductors 65 of the first substrate 10 and the second substrate 20 with the metal bonding material 73. This ensures a connection surface between the first substrate 10 and the second substrate 20 other than the bonding surfaces of the IGBT 50 and the diode 54, improving reliability.

The collector conductor 60, emitter conductor 61, cathode conductor 63, and anode conductor 64 form a heat dissipation fin 75 on the side opposite the connection surface of the IGBT 50 and diode 54. This allows a heat dissipation path to be formed from the IGBT 50 and diode 54 to the heat dissipation fin 75 without passing through an insulating member, and since it is directly cooled by a refrigerant such as oil, it is possible to suppress an increase in thermal resistance and increase the output of the power conversion device.

As shown in Figures 1 and 4, the second substrate 20 forms through holes 76 that connect the IGBT storage recess 70 and diode storage recess 71 on the first substrate 10 to the outer surface of the second substrate 20. The IGBT 50 and diode 54 are sealed by filling the through holes 76 with a resin material 77 such as a liquid hardening resin. In the conventional main circuit structure composed of wire bonding or lead frames, in order to ensure reliability by transfer molding, the dimensional variation of the components causes partial resin covering, etc., and there is a problem that the heat dissipation surface cannot be reliably exposed. In contrast, in the present embodiment, the process that prevents the exposure of the heat dissipation surface is eliminated, improving manufacturability.

As shown in FIG. 3, the second power circuit section 40 includes an IGBT 50, a diode 54, a collector conductor 60, an emitter conductor 61, a gate conductor pattern 62, a cathode conductor 63, and an anode conductor 64. The main configuration of the second power circuit section 40 is roughly the inverted structure of the first power circuit section 30. Since there is no configuration unique to the second power circuit section 40, we will continue with the explanation of the power conversion device 100 as a whole.

As shown on the left in FIG. 1 and in the upper part of FIG. 3, the collector conductor 60 and the cathode conductor 63 are connected to the positive power supply conductor pattern 66. As shown in the lower part of FIG. 3, the emitter conductor 61 and the anode conductor 64 are connected to the AC output conductor pattern 68. As shown in the lower part of FIG. 2, the collector conductor 60 and the cathode conductor 63 of the first power circuit section 30 are also connected to the AC output conductor pattern 68. As shown in the upper part of FIG. 2, the emitter conductor 61 and the anode conductor 64 of the first power circuit section 30 are connected to the negative power supply conductor pattern 67.

As shown in FIG. 1, the positive power supply conductor pattern 66 and the negative power supply conductor pattern 67 are provided with a positive power supply terminal 661 and a negative power supply terminal 671, respectively, and the electrical energy required to drive the electric motor is supplied from the battery. The AC output conductor pattern 68 is provided with an AC output terminal 681 shown in the upper part of FIG. 1, and outputs electrical energy to drive the electric motor. The positive power supply terminal 661, the negative power supply terminal 671, and the AC output terminal 681 shown in FIG. 1 are connected to and penetrate the first board 10 and the second board 20, and the upper and lower surfaces of both boards are connected around the terminal parts by vias not shown. This expands the path area of the current path connected to the battery and the electric motor, preventing heat concentration.

As shown in FIG. 1, a capacitor 80 that smoothes the voltage applied to the power conversion device 100 is mounted on the positive power supply conductor pattern 66 and the negative power supply conductor pattern 67. As a result, when the power conversion device 100 is switched, the current flowing out from the capacitor 80 flows into the capacitor 80 via the second power circuit unit 40 and the first power circuit unit 30. As a result, the path of the transient current during switching is completed only within the first board 10 and the second board 20, and the inductance can be reduced by shortening the current path. Furthermore, since the transient current path during switching is completed within the first board 10 and the second board 20, the current paths of the first board 10 and the second board 20 become closer, and opposing currents flow through the first power circuit unit 30 and the second power circuit unit 40, thereby reducing the inductance. In addition, a bus bar for connecting the capacitor 80 is not required, improving manufacturability.

As shown in Figures 1 to 3, the gate conductor pattern 62 is electrically connected to the upper surface of the second substrate 20 through vias 74 in the first substrate 10 and the second substrate 20. As shown in Figures 2 and 3, a substrate bonding recess 72 is provided near the vias 74 in the first substrate 10, and the first substrate 10 and the second substrate 20 are bonded by a substrate bonding material. As shown in Figure 1, control circuits 90 for the first power circuit section 30 and the second power circuit section 40 are provided on the second substrate 20 and connected to the respective gate conductor patterns 62. This reduces the inductance of the control signal, preventing a decrease in element driving performance and thus preventing an increase in loss.

With the above configuration, the power conversion device 100 supplies the electric energy required to drive the motor from the battery to the first power circuit section 30 and the second power circuit section 40, and controls the AC power output from the AC output terminal 681 provided on the AC output conductor pattern 68. By configuring the first power circuit section 30 and the second power circuit section 40, the capacitor 80, and the control circuit 90, which are all components, on the first board 10 and the second board 20, a complex bus bar is not required, improving manufacturability. When the power conversion device 100 is switched, the current flowing out of the capacitor 80 flows into the capacitor 80 via the first power circuit section 30 and the second power circuit section 40. This shortens the transient current path during switching and reduces inductance.

According to the above-described first embodiment, the following advantageous effects can be obtained.
(1) The power conversion device 100 includes an IGBT 50, which is a semiconductor element, and a first substrate 10 and a second substrate 20 arranged opposite to each other. The first substrate 10 has a first main surface 10P facing the second substrate 20 and a first sub-surface 10Q on the opposite side to the first main surface 10P. The second substrate 20 has a second main surface 20P facing the first substrate 10 and a second sub-surface 20Q on the opposite side to the second main surface 20P. A first conductor exposed on the first sub-surface 10Q, for example, a collector conductor 60 of the first power circuit section 30, is embedded in the first substrate 10. A second conductor exposed on the second sub-surface 20Q, for example, an emitter conductor 61 of the first power circuit section 30, is embedded in the second substrate 20. The IGBT 50 is disposed between the collector conductor 60 and the emitter conductor 61. The IGBT 50 is electrically connected to the collector conductor 60 and the emitter conductor 61. Therefore, a bus bar with a complex shape as in the conventional art is not required, and the power conversion device 100 is excellent in manufacturability. In addition, the collector conductor 60 and the emitter conductor 61 in contact with the IGBT 50 are metal lumps, so they have good thermal conductivity, and are exposed to the outer periphery, so they have excellent heat dissipation. In other words, the power conversion device 100 is excellent in manufacturability and heat dissipation.

(2) The collector conductor 60 of the first power circuit section 30 is exposed to both the first main surface 10P and the first sub-surface 10Q. The emitter conductor 61 of the first power circuit section 30 is exposed to both the second main surface 20P and the second sub-surface 20Q. The emitter conductor 61 of the first power circuit section 30 forms a recessed portion, the IGBT storage recess 70, and the IGBT 50 is stored inside this IGBT storage recess 70.

(3) The second substrate 20 has vias 74 formed therein, which are through holes that connect the IGBT-storing recess 70 to the outside of the second substrate 20, and the area of the IGBT-storing recess 70 excluding the IGBT 50 is filled with a resin member 77. Therefore, the resin member 77 prevents foreign matter from adhering to the IGBT 50 and prevents adverse effects on the IGBT 50 due to vibration.

(4) The IGBT storage recess 70 in which the IGBT 50 is housed is formed in the collector conductor 60 of the first power circuit section 30, but is not formed in the opposing emitter conductor 61. The emitter conductor 61 is formed flush with the second main surface 20P of the second substrate 20. The IGBT 50 has a collector electrode 51 connected to the collector conductor 60, an emitter electrode 52 connected to the emitter conductor 61, and a gate electrode 53 connected to the gate conductor pattern 62 of the second substrate 20. Therefore, since the IGBT storage recess 70 is formed only in the first substrate 10, it is easier to manage the tolerance than when recesses are provided on both substrates. In addition, if the IGBT 50 is arranged at the boundary between the first substrate 10 and the second substrate 20, a physical load will be generated on the IGBT 50 when a force that twists the power conversion device 100 is generated. However, in this embodiment, the IGBT 50 is protected because it is placed inside the first substrate 10.

(5) Each of the first substrate 10 and the second substrate 20 has a plurality of dummy conductors 65 different from the collector conductor 60 of the first power circuit section 30 and the emitter conductor 61 of the first power circuit section 30. The first substrate 10 and the second substrate 20 are connected to each other by connecting the plurality of dummy conductors 65 with a metal bonding material 73. The dummy conductor 65 included in the first substrate 10 has a substrate bonding recess 72 formed therein to accommodate the metal bonding material 73. Therefore, the first substrate 10 and the second substrate 20 are firmly connected, and the force generated in the IGBT 50 when a strong force is applied to the power conversion device 100 can be reduced.

(6) The first substrate 10 and the second substrate 20 have the collector conductor 60 and the emitter conductor 61 of the second power circuit section 40 that penetrate the respective substrates in addition to the collector conductor 60 and the emitter conductor 61 of the first power circuit section 30. The IGBT 50 of the second power circuit section 40 is connected to the collector conductor 60 and the emitter conductor 61 of the second power circuit section 40 in an inverted orientation to the IGBT 50 of the first power circuit section 30. Therefore, two IGBTs 50 can be held using one set of substrates.

(7) The collector conductor 60, the IGBT 50, and the emitter conductor 61 are aligned in a first direction, i.e., the vertical direction in Figs. 2 to 4. The first substrate 10 has an AC output conductor pattern 68 that extends in a second direction perpendicular to the first direction and electrically connects the collector conductor 60 of the first power circuit unit 30 and the emitter conductor 61 of the second power circuit unit 40. The second substrate 20 has a negative power supply conductor pattern 67 that extends in the second direction and is electrically connected to the emitter conductor 61 of the first power circuit unit 30, and a positive power supply conductor pattern 66 that extends in the second direction and is electrically connected to the collector conductor 60 of the second power circuit unit 40, but is not connected to the negative power supply conductor pattern 67. The power conversion device 100 includes a capacitor 80 that spans the positive power supply conductor pattern 66 and the negative power supply conductor pattern 67. Therefore, the upper arm circuit and the lower arm circuit for one phase can be configured using the first substrate 10, the second substrate 20, and two IGBTs 50.

(8) The collector conductor 60 has a heat dissipation fin 75 connected to the first minor surface 10Q. The emitter conductor 61 has a heat dissipation fin 75 connected to the second minor surface 20Q. Therefore, the power conversion device 100 can dissipate heat efficiently.

(Variation 1)
In the first embodiment described above, both the collector conductor 60 and the emitter conductor 61 penetrate the substrate and are exposed on both the main surface and the sub-surface. However, the collector conductor 60 and the emitter conductor 61 only need to be exposed on at least the outer periphery side, i.e., the sub-surface side, and do not have to be exposed on the main surface side. In other words, the collector conductor 60 and the emitter conductor 61 do not have to penetrate the substrate.

Figure 5 shows a part of the first power circuit section 30 in the first modified example, which corresponds to the center of Figure 2. In Figure 5, the emitter conductor 61 is exposed to the second main surface 20P as in the first embodiment, but the collector conductor 60 is not exposed to the first main surface 10P. Specifically, the collector conductor end 60X of the emitter conductor 61 of the first power circuit section 30 that is closest to the first main surface 10P is located at a position recessed from the first main surface 10P. The configuration of this modified example also has good heat dissipation and good manufacturability as in the first embodiment.

(Variation 2)
In the above-described first embodiment, the collector conductor 60 is provided with the IGBT accommodating recess 70 which is a recess for accommodating the IGBT 50, but no recess is provided in the emitter conductor 61. However, instead of providing a recess in the collector conductor 60, a recess may be provided in the emitter conductor 61, or recesses may be provided in both the collector conductor 60 and the emitter conductor 61.

(Variation 3)
In the above-described first embodiment, the IGBT accommodating recess 70 is filled with the resin member 77. However, it is not essential that the IGBT accommodating recess 70 is filled with the resin member 77, and the IGBT accommodating recess 70 does not have to be filled with the resin member 77.

(Variation 4)
In the first embodiment described above, the collector conductor 60 and the emitter conductor 61 have the heat dissipation fins 75 on the outer periphery. However, it is not essential that the collector conductor 60 and the emitter conductor 61 have the heat dissipation fins 75, and at least one of the collector conductor 60 and the emitter conductor 61 does not have to have the heat dissipation fins 75.

(Variation 5)
In the first embodiment described above, the dummy conductor 65 and the metal bonding material 73 are used to strengthen the connection between the first substrate 10 and the second substrate 20. However, the power conversion device 100 does not necessarily have to include the dummy conductor 65 and the metal bonding material 73.

--Second embodiment--
A second embodiment of the power conversion device will be described with reference to Fig. 6. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the first embodiment. In this embodiment, the main difference from the first embodiment is the arrangement of the AC output terminals.

Figure 6 is a schematic diagram of the power conversion device 100A in the second embodiment. The AC output terminal 681 is disposed adjacent to the positive power supply terminal 661 and the negative power supply terminal 671. Specifically, the AC output terminal 681 is shown at the bottom of the figure in Figure 6, whereas it is shown at the top of the figure in Figure 1. In the second embodiment, all of the main circuit wiring connected to the power conversion device 100 can be connected from the same direction, improving productivity when assembling the battery and the electric motor.

--Third embodiment--
A third embodiment of the power conversion device will be described with reference to Fig. 7. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the first embodiment. The third embodiment differs from the first embodiment mainly in that a plurality of capacitors 80 are provided.

Figure 7 is a schematic diagram of a power conversion device 100B in the third embodiment. The power conversion device 100B includes two or more capacitors 80, and in the example shown in Figure 7, includes three capacitors 80. By providing multiple capacitors 80 mounted on the positive power supply conductor pattern 66 and the negative power supply conductor pattern 67, the transient current path during switching is divided into multiple paths, reducing inductance. Furthermore, by arranging the capacitor 80 between the first power circuit section 30 and the second power circuit section 40, the transient current path during switching is shortened, reducing inductance.

--Fourth embodiment--
A fourth embodiment of the power conversion device will be described with reference to Figures 8 and 9. In the following description, the same components as those in the first embodiment are denoted by the same reference numerals, and differences will be mainly described. Points that are not particularly described are the same as those in the first embodiment. The fourth embodiment differs from the first embodiment mainly in that it includes a reverse conducting IGBT.

Figure 8 is a schematic diagram of a power conversion device 100C in the fourth embodiment. Figure 9 is a cross-sectional view taken along line IX-IX of Figure 8. The first power circuit section 30 and the second power circuit section 40 are equipped with a reverse conducting IGBT 57 in which an IGBT and a diode are integrated. This reduces the mounting area of the semiconductor element, making it possible to miniaturize the power conversion device 100. Furthermore, the transient current path during switching is shortened, reducing inductance.

In each of the above-mentioned embodiments and variations, the functional block configurations are merely examples. Some functional configurations shown as separate functional blocks may be configured together, or a configuration shown in a single functional block diagram may be divided into two or more functions. In addition, some of the functions of each functional block may be provided by other functional blocks.

The above-mentioned embodiments and modifications may be combined with each other. Although various embodiments and modifications have been described above, the present invention is not limited to these. Other aspects that are conceivable within the scope of the technical concept of the present invention are also included within the scope of the present invention.

10...First substrate 10P...First main surface 10Q...First sub-surface 20...Second substrate 20P...Second main surface 20Q...Second sub-surface 30...First power circuit section 40...Second power circuit section 60...Collector conductor 61...Emitter conductor 63...Cathode conductor 64...Anode conductor 65...Dummy conductor 70...IGBT accommodating recess 72...Substrate bonding recess 73...Metal bonding material 74...Via 75...Heat dissipation fin 77...Resin member 80...Capacitor 100, 100A, 100B, 100C...Power conversion device

Claims (6)

A semiconductor element;
a first substrate and a second substrate disposed opposite each other;
The first substrate has a first main surface facing the second substrate and a first sub-surface opposite to the first main surface,
The second substrate has a second main surface facing the first substrate and a second sub-surface opposite to the second main surface,
a first conductor is embedded in the first substrate and is exposed on the first minor surface;
a second conductor is embedded in the second substrate and is exposed on the second minor surface;
the semiconductor element is disposed between the first conductor and the second conductor;
the semiconductor element is electrically connected to the first conductor and the second conductor ;
the first conductor is exposed on both the first major surface and the first minor surface;
the second conductor is exposed on both the second major surface and the second minor surface;
One or both of the first conductor and the second conductor form a recess;
The semiconductor element is housed in the recess . 2. The power conversion device according to claim 1 ,
At least one of the first substrate and the second substrate has a through hole formed therein, the through hole connecting the recess and an outside of the power conversion device;
The recessed portion is filled with a resin member in an area other than the semiconductor element. 2. The power conversion device according to claim 1 ,
the recess is formed only in the first conductor;
the second conductor is formed flush with the second main surface of the second substrate;
The semiconductor element has a collector electrode connected to the first conductor, an emitter electrode connected to the second conductor, and a gate electrode connected to another conductor of the second substrate. A semiconductor element;
a first substrate and a second substrate disposed opposite each other;
The first substrate has a first main surface facing the second substrate and a first sub-surface opposite to the first main surface,
The second substrate has a second main surface facing the first substrate and a second sub-surface opposite to the second main surface,
a first conductor is embedded in the first substrate and is exposed on the first minor surface;
a second conductor is embedded in the second substrate and is exposed on the second minor surface;
the semiconductor element is disposed between the first conductor and the second conductor;
the semiconductor element is electrically connected to the first conductor and the second conductor ;
the first substrate and the second substrate have third and fourth conductors different from the first and second conductors,
the third conductor and the fourth conductor are connected by a metal bonding material to connect the first substrate and the second substrate;
A power conversion device , wherein at least one of the third conductor and the fourth conductor has a second recess formed therein to accommodate the metal bonding material . A semiconductor element;
a first substrate and a second substrate disposed opposite each other;
The first substrate has a first main surface facing the second substrate and a first sub-surface opposite to the first main surface,
The second substrate has a second main surface facing the first substrate and a second sub-surface opposite to the second main surface,
a first conductor is embedded in the first substrate and is exposed on the first minor surface;
a second conductor is embedded in the second substrate and is exposed on the second minor surface;
the semiconductor element is disposed between the first conductor and the second conductor;
the semiconductor element is electrically connected to the first conductor and the second conductor ;
the first substrate and the second substrate have fifth and sixth conductors penetrating through each substrate in addition to the first and second conductors;
a power conversion device, wherein another semiconductor element is connected to the fifth conductor and the sixth conductor in an inverted orientation relative to the semiconductor element ; 6. The power conversion device according to claim 5 ,
the first conductor, the semiconductor element, and the second conductor are aligned in a first direction;
the first substrate further includes a seventh conductor extending in a second direction perpendicular to the first direction and electrically connecting the first conductor and the fifth conductor;
the second substrate further includes an eighth conductor extending in the second direction and electrically connected to the second conductor, and a ninth conductor extending in the second direction and electrically connected to the sixth conductor but not connected to the eighth conductor;
The power conversion device further includes a capacitor spanning the eighth conductor and the ninth conductor.

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