Bidirectional switch circuit and power conversion device

Abstract

To obtain a bidirectional switch circuit and a power converter that can be miniaturized.SOLUTION: A bidirectional switch circuit according to the present disclosure includes a first semiconductor device having a first back electrode electrically connected to a first top electrode and a first pattern, a second semiconductor device having a second back electrode electrically connected to a second top electrode and a second pattern, a first diode having a first anode electrode and a first cathode electrode electrically connected to the first pattern, a second diode having a second anode electrode and a second cathode electrode electrically connected to the second pattern, a first wiring that electrically connects the first top electrode and the second anode electrode, and a second wiring electrically connecting the second top electrode and the first anode electrode, and the first top electrode, the second top electrode, the first anode electrode, and the second anode electrode are electrically connected to each other.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to a bidirectional switch circuit and a power conversion device.

Background Art

[0002] Patent Document 1 discloses a bidirectional switch module. In this bidirectional switch module, a first semiconductor device having a bonding electrode connected to a first node of a bidirectional switch circuit is placed on a first metal base plate serving as a heat dissipation plate. Also, a second semiconductor device having a bonding electrode connected to a second node of the bidirectional switch circuit is placed on a second metal base plate which also serves as a heat dissipation plate. The bonding electrode of the first semiconductor device is set to the same potential as the first metal base plate. Also, the bonding electrode of the second semiconductor device is set to the same potential as the second metal base plate. Then, each metal base plate and the non-bonding electrodes of each semiconductor device are connected by metal wires respectively to form a bidirectional switch circuit.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the bidirectional switch circuit of Patent Document 1, in order to perform emitter-common type circuit connection, a pattern of emitter potential is arranged. For this reason, the area of the circuit may become large.

[0005] The present disclosure has been made to solve the above problems, and an object thereof is to obtain a bidirectional switch circuit and a power conversion device capable of miniaturization.

Means for Solving the Problems

[0006] The bidirectional switch circuit according to the present disclosure includes a first pattern, a second pattern, a first gate electrode, a first back surface electrode, and a first top surface electrode provided on the side opposite to the first back surface electrode. The first back surface electrode is provided on the first pattern and is electrically connected to the first pattern, and includes a first semiconductor device. The bidirectional switch circuit further includes a second gate electrode, a second back surface electrode, and a second top surface electrode provided on the side opposite to the second back surface electrode. The second back surface electrode is provided on the second pattern and is electrically connected to the second pattern, and includes a second semiconductor device. The bidirectional switch circuit further includes a first cathode electrode and a first anode electrode provided on the side opposite to the first cathode electrode. The first cathode electrode is provided on the first pattern and is electrically connected to the first pattern, and includes a first diode. The bidirectional switch circuit further includes a second cathode electrode and a second anode electrode provided on the side opposite to the second cathode electrode. The second cathode electrode is provided on the second pattern and is electrically connected to the second pattern, and includes a second diode. The bidirectional switch circuit further includes a first wiring that electrically connects the first top surface electrode and the second anode electrode, and a second wiring that electrically connects the second top surface electrode and the first anode electrode. The first top surface electrode, the second top surface electrode, the first anode electrode, and the second anode electrode are electrically connected to each other. The first top surface electrode and the second top surface electrode, the first anode electrode and the second anode electrode, the first top surface electrode and the first anode electrode, or the second top surface electrode and the second anode electrode are electrically connected by a connection portion, and the connection portion is provided separately from the first wiring and the second wiring. , the connection part has a driving pattern, and a voltage is supplied to the first top electrode and the second top electrode from the outside through the driving pattern. is. The bidirectional switch circuit according to the present disclosure includes a first pattern, a second pattern, a first gate electrode, a first back surface electrode, and a first top electrode provided on the opposite side of the first back surface electrode, wherein the first back surface electrode is provided on the first pattern and is electrically connected to the first pattern, a first semiconductor device; a second gate electrode, a second back surface electrode, and a second top electrode provided on the opposite side of the second back surface electrode, wherein the second back surface electrode is provided on the second pattern and is electrically connected to the second pattern, a second semiconductor device; a first cathode electrode, and a first anode electrode provided on the opposite side of the first cathode electrode, wherein the first cathode electrode is provided on the first pattern and is electrically connected to the first pattern, a first diode; a second cathode electrode, and a second anode electrode provided on the opposite side of the second cathode electrode, wherein the second cathode electrode is provided on the second pattern and is electrically connected to the second pattern, a second diode; a first wiring for electrically connecting the first top electrode and the second anode electrode; and a second wiring for electrically connecting the second top electrode and the first anode electrode, wherein the first top electrode, the second top electrode, the first anode electrode, and the second anode electrode are electrically connected to each other, the first top electrode and the second top electrode, the first anode electrode and the second anode electrode, the first top electrode and the first anode electrode, or the second top electrode and the second anode electrode are electrically connected by a connection part, the connection part is provided separately from the first wiring and the second wiring, and a member for connecting the first top electrode, the second top electrode, the first anode electrode, and the second anode electrode to each other includes a fine metal wire.

Advantages of the Invention

[0007] In the bidirectional switch circuit according to the present disclosure, the first top surface electrode and the second anode electrode are electrically connected by the first wiring, and the second top surface electrode and the first anode electrode are electrically connected by the second wiring. Further, the first top surface electrode, the second top surface electrode, the first anode electrode, and the second anode electrode are electrically connected to each other. Therefore, it is not necessary to add a pattern for the emitter potential, and miniaturization is possible.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

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Figure 8

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Figure 10

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Figure 12

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Figure 14

Modes for Carrying Out the Invention

[0009] The bidirectional switch circuit and the power conversion device according to each embodiment will be described with reference to the drawings. The same or corresponding components may be denoted by the same reference numerals, and repeated descriptions may be omitted.

[0010] Embodiment 1. FIG. 1 is a diagram for explaining a bidirectional switch circuit 100 according to Embodiment 1. FIG. 2 is a plan view of the bidirectional switch circuit 100 according to Embodiment 1. The bidirectional switch circuit 100 includes semiconductor devices Tr1 and Tr2, and diodes Di1 and Di2. The semiconductor devices Tr1 and Tr2 are IGBTs. The diode Di1 is connected in anti-parallel with the semiconductor device Tr1 such that the anode and the emitter of the semiconductor device Tr1 are at the same potential. Similarly, the diode Di2 is connected in anti-parallel with the semiconductor device Tr2 such that the anode and the emitter of the semiconductor device Tr2 are at the same potential.

[0011] The bidirectional switch circuit 100 includes patterns 10 and 20 disposed on an insulating substrate. The patterns 10 and 20 are collector patterns. The semiconductor device Tr1 has a gate electrode G1, a back surface electrode C1, and a top surface electrode Es1 provided on the side opposite to the back surface electrode C1. The back surface electrode C1 is provided on the pattern 10 and is electrically connected to the pattern 10. The back surface electrode C1 is a collector electrode, and the top surface electrode Es1 is an emitter electrode.

[0012] The semiconductor device Tr2 has a gate electrode G2, a back surface electrode C2, and a top surface electrode Es2 provided on the side opposite to the back surface electrode C2. The back surface electrode C2 is provided on the pattern 20 and is electrically connected to the pattern 20. The back surface electrode C2 is a collector electrode, and the top surface electrode Es2 is an emitter electrode.

[0013] The diode Di1 has a cathode electrode Ca1 and an anode electrode A1 provided on the side opposite to the cathode electrode Ca1. The cathode electrode Ca1 is provided on the pattern 10 and is electrically connected to the pattern 10. The diode Di2 has a cathode electrode Ca2 and an anode electrode A2 provided on the side opposite to the cathode electrode Ca2. The cathode electrode Ca2 is provided on the pattern 20 and is electrically connected to the pattern 20.

[0014] The wiring 41 electrically connects the top electrode Es1 and the anode electrode A2. The wiring 43 electrically connects the top electrode Es2 and the anode electrode A1. Also, the top electrode Es1 and the top electrode Es2 are electrically connected to each other by a wiring 45 which is a connection part. The wirings 41, 43, and 45 are, for example, thin metal wires such as aluminum wires. By the above connections, the emitter electrodes and the anode electrodes of each chip become the same potential.

[0015] An emitter drive pattern 12 is electrically connected to the top electrode Es1 via a wiring. Gate patterns 14 and 24 are electrically connected to the gate electrodes G1 and G2 respectively via wirings.

[0016] Also, the patterns 10 and 20 are electrically connected to terminals (not shown) for connecting to the outside of the module respectively. In the bidirectional switch circuit 100, it is possible to flow current in both directions between the patterns 10 and 20 via the semiconductor device Tr1 and the diode Di2 or the semiconductor device Tr2 and the diode Di1.

[0017] Figure 3 is a plan view of a bidirectional switch circuit 101 according to a comparative example. In the bidirectional switch circuit 101 according to the comparative example, an emitter pattern 30 is provided to make the emitter electrodes and the anode electrodes of a plurality of chips have the same potential. Further, emitter drive patterns 12 and 22 are provided for the semiconductor devices Tr1 and Tr2 respectively. For this reason, there is a possibility that the area of the circuit becomes large.

[0018] In contrast, in the bidirectional switch circuit 100 according to the present embodiment, the wiring 41, 43, 45 can make the emitter electrodes of the semiconductor devices Tr1, Tr2 and the anode electrodes of the diodes Di1, Di2 at the same potential. Therefore, the emitter pattern can be omitted and the circuit can be miniaturized. Further, since the emitter drive patterns 12 of the semiconductor devices Tr1, Tr2 can be shared, the circuit area can be further reduced.

[0019] Also, a normal IGBT does not have a breakdown voltage against reverse voltage. In contrast, in the present embodiment, the IGBT and the diode can be connected in antiparallel. By the antiparallel connection, it is possible to prevent a voltage equal to or higher than the forward voltage VF of the diode from being applied to the IGBT. Therefore, reverse breakdown of the IGBT can be suppressed.

[0020] As a modification of the present embodiment, the connection position of the wiring 45 is not limited to the position shown in FIG. 2 as long as the upper surface electrodes Es1, the upper surface electrode Es2, the anode electrode A1, and the anode electrode A2 are electrically connected to each other. For example, a short-circuit method as shown in FIGS. 4 to 6 is also possible. FIG. 4 is a plan view of a bidirectional switch circuit 100a according to a first modification of Embodiment 1. In this way, the anode electrode A1 and the anode electrode A2 may be electrically connected by the wiring 45a. FIG. 5 is a plan view of a bidirectional switch circuit 100b according to a second modification of Embodiment 1. In this way, the upper surface electrode Es1 and the anode electrode A1 may be electrically connected by the wiring 45b. FIG. 6 is a plan view of a bidirectional switch circuit 100c according to a third modification of Embodiment 1. In this way, the upper surface electrode Es2 and the anode electrode A2 may be electrically connected by the wiring 45c.

[0021] In the present embodiment, the semiconductor devices Tr1, Tr2 are assumed to be IGBTs. However, the semiconductor devices Tr1, Tr2 may be switching elements such as MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors).

[0022] In addition, the fine metal wires used as the wirings 41, 43, and 45 are formed of, for example, copper, an Al alloy, or Al coated with copper. Thereby, heat generation due to the current flowing through the fine metal wires can be reduced. Therefore, the current density per wiring can be improved and the number of wirings can be reduced. Further, when the number of wirings is not reduced, reduction in the temperature of the fine metal wires and extension of the life of the device can be expected. Note that such fine metal wires may be employed in a part of the member that connects the top electrode Es1, the top electrode Es2, the anode electrode A1, and the anode electrode A2 to each other.

[0023] The member that connects the top electrode Es1, the top electrode Es2, the anode electrode A1, and the anode electrode A2 to each other may include a metal plate. The metal plate is, for example, a lead frame material or a ribbon material. Thereby, reduction in the temperature of the connection member and extension of the life of the device can be expected. Also, the wiring can be simplified.

[0024] At least one of the semiconductor devices Tr1, Tr2, and the diodes Di1, Di2 may be formed of a wide bandgap semiconductor. The wide bandgap semiconductor is, for example, silicon carbide, a gallium nitride-based material, or diamond. Thereby, loss in the bidirectional switch circuit 100 can be reduced.

[0025] These modifications can be appropriately applied to the bidirectional switch circuit and the power conversion device according to the following embodiments. Note that the bidirectional switch circuit and the power conversion device according to the following embodiments have many common points with those of Embodiment 1, and thus, description will be mainly focused on the differences from Embodiment 1.

[0026] Embodiment 2. FIG. 7 is a plan view of the bidirectional switch circuit 200 according to Embodiment 2. The bidirectional switch circuit 200 of the present embodiment is different from the bidirectional switch circuit 100 in that the upper surface electrodes Es1 and Es2 are connected via the emitter drive pattern 212. Other configurations are the same as those of the bidirectional switch circuit 100. In the present embodiment, the connection portion connecting the upper surface electrode Es1 and the upper surface electrode Es2 has a wiring 245, an emitter drive pattern 212, and a wiring 246. By such a connection, the emitter electrodes and the anode electrodes of the respective chips become the same potential.

[0027] The emitter drive pattern 212 is electrically connected to an emitter drive terminal (not shown) that is connected to the outside of the bidirectional switch circuit 200 in order to input signals to the semiconductor devices Tr1 and Tr2. That is, the emitter drive pattern 212 is electrically connected to an input signal circuit that sends an input signal to the semiconductor devices Tr1 and Tr2. The same applies to the emitter drive pattern 12 of Embodiment 1. That is, a voltage is supplied from the outside to the upper surface electrode Es1 and the upper surface electrode Es2 via the emitter drive patterns 12 and 212.

[0028] On the other hand, the emitter pattern 30 according to the comparative example shown in FIG. 3 is not electrically connected to any external terminal and is different from the emitter drive patterns 12 and 212.

[0029] In the comparative example shown in FIG. 3, emitter drive patterns 12 and 22 are provided for the semiconductor devices Tr1 and Tr2, respectively. On the other hand, in the present embodiment, the semiconductor devices Tr1 and Tr2 share the emitter drive pattern 212. Further, the upper surface electrodes Es1 and Es2 are connected via the emitter drive pattern 212. This enables miniaturization and component reduction of the bidirectional switch circuit 200.

[0030] Furthermore, in the present embodiment, by sharing the emitter drive pattern 212 of the semiconductor devices Tr1 and Tr2, the degree of freedom in circuit design can be improved. Also, by symmetrically wiring the semiconductor devices Tr1 and Tr2 with respect to the emitter drive pattern 212, the difference in losses during the switching operations of the semiconductor devices Tr1 and Tr2 can be reduced.

[0031] As a modification of the present embodiment, the connection position of the emitter drive pattern 212 is not limited to the position shown in FIG. 7 as long as the top electrodes Es1, Es2, the anode electrodes A1, and A2 are electrically connected to each other. For example, connection methods as shown in FIGS. 8 - 10 are also possible.

[0032] FIG. 8 is a plan view of a bidirectional switch circuit 200a according to a first modification of Embodiment 2. In the bidirectional switch circuit 200a, the anode electrode A1 and the anode electrode A2 are electrically connected via wiring 245a, the emitter drive pattern 212, and wiring 246a. FIG. 9 is a plan view of a bidirectional switch circuit 200b according to a second modification of Embodiment 2. In the bidirectional switch circuit 200b, the top electrode Es1 and the anode electrode A1 are electrically connected via wiring 245b, the emitter drive pattern 212, and wiring 246b. FIG. 10 is a plan view of a bidirectional switch circuit 200c according to a third modification of Embodiment 2. In the bidirectional switch circuit 200c, the top electrode Es2 and the anode electrode A2 are electrically connected via wiring 245c, the emitter drive pattern 212, and wiring 246c.

[0033] Embodiment 3. FIG. 11 is a plan view of a bidirectional switch circuit 300 according to Embodiment 3. In the present embodiment, it is different from Embodiment 2 in that the semiconductor device Tr1 and the diode Di1 are formed on one chip Tr3, and the semiconductor device Tr2 and the diode Di2 are formed on one chip Tr4. Other configurations are the same as those of Embodiment 2. The semiconductor device Tr1 and the diode Di1 constitute an RC (Reverse-Conducting)-IGBT. The semiconductor device Tr2 and the diode Di2 constitute an RC-IGBT.

[0034] On pattern 10, the collector electrode and the cathode electrode of chip Tr3, which is an RC-IGBT, are provided. On pattern 20, the collector electrode and the cathode electrode of chip Tr4, which is an RC-IGBT, are provided. The emitter electrode of chip Tr3 and the anode electrode of chip Tr4 are electrically connected by wiring 341. The emitter electrode of chip Tr4 and the anode electrode of chip Tr3 are electrically connected by wiring 341. Further, the emitter electrode of chip Tr3 and the emitter electrode of chip Tr4 are electrically connected via wiring 345, emitter drive pattern 312, and wiring 346.

[0035] In the present embodiment, by configuring the switching element and the diode as one chip, the circuit area and the number of components can be further reduced.

[0036] As a first modification of the present embodiment, the anode electrode of chip Tr3 and the anode electrode of chip Tr4 may be electrically connected via wiring 345, emitter drive pattern 312, and wiring 346. FIG. 12 is a plan view of a bidirectional switch circuit 300a according to a second modification of Embodiment 3. Like the bidirectional switch circuit 300a, the emitter electrode and the anode electrode of chip Tr3 may be electrically connected via wiring 345a and emitter drive pattern 312. FIG. 13 is a plan view of a bidirectional switch circuit 300b according to a third modification of Embodiment 3. Like the bidirectional switch circuit 300b, the emitter electrode and the anode electrode of chip Tr4 may be electrically connected via wiring 345b and emitter drive pattern 312.

[0037] Also, in the bidirectional switch circuit 300, the emitter electrode of chip Tr3 and the emitter electrode of chip Tr4 may be directly connected by wiring 345 without passing through the emitter drive pattern 312. In the present embodiment, an example of an RC-IGBT chip is shown, but 、A switching element and a diode may be formed on one MOSFET chip. In this case, the diodes Di1 and Di2 are formed as body diodes of the MOSFET.

[0038] Embodiment 4. FIG. 14 is a diagram for explaining a power conversion device 800 according to Embodiment 4. The power conversion device 800 includes the bidirectional switch circuit and the inverter circuit 50 described in Embodiments 1 to 3. In FIG. 14, an example in which the power conversion device 800 includes the bidirectional switch circuit 100 is shown. The power conversion device 800 is, for example, a three-level inverter circuit. The power conversion device 800 may be a converter circuit. By using the bidirectional switch circuit 100, miniaturization of the power conversion device 800 and its application system becomes possible.

[0039] Note that the technical features described in each embodiment may be used in appropriate combination.

Description of Reference Numerals

[0040] 10 pattern, 12 emitter drive pattern, 14 gate pattern, 20 pattern, 30 emitter pattern, 41, 43, 45, 45a, 45b, 45c wiring, 50 inverter circuit, 100, 100a, 100b, 100c, 101, 200, 200a, 200b, 200c bidirectional switch circuit, 212 emitter drive pattern, 245, 245a, 245b, 245c, 246, 246a, 246b, 246c wiring, 300, 300a, 300b bidirectional switch circuit, 312 emitter drive pattern, 341, 345, 345a, 345b, 346 wiring, 800 power conversion device, A1, A2 anode electrode, C1, C2 back surface electrode, Ca1, Ca2 cathode electrode, Di1, Di2 diode, Es1, Es2 upper surface electrode, G1, G2 gate electrode, Tr1, Tr2 semiconductor device, Tr3, Tr4 chip

Claims

1. a first pattern, a second pattern, a first gate electrode, a first back electrode, and a first top electrode provided on the side opposite to the first back electrode, and a first semiconductor device having the first back electrode provided on the first pattern and electrically connected to the first pattern; a second gate electrode, a second back electrode, and a second top electrode provided on the side opposite to the second back electrode, and a second semiconductor device having the second back electrode provided on the second pattern and electrically connected to the second pattern; a first cathode electrode and a first anode electrode provided on the side opposite to the first cathode electrode, and a first diode having the first cathode electrode provided on the first pattern and electrically connected to the first pattern; a second cathode electrode and a second anode electrode provided on the side opposite to the second cathode electrode, and a second diode having the second cathode electrode provided on the second pattern and electrically connected to the second pattern; a first wiring electrically connecting the first top electrode and the second anode electrode; a second wiring electrically connecting the second top electrode and the first anode electrode; comprising the first top electrode, the second top electrode, the first anode electrode, and the second anode electrode are electrically connected to each other; the first top electrode and the second top electrode, the first anode electrode and the second anode electrode, the first top electrode and the first anode electrode, or the second top electrode and the second anode electrode are electrically connected by a connection portion; the connection portion is provided separately from the first wiring and the second wiring; the connection portion has a drive pattern; a bidirectional switch circuit, wherein a voltage is supplied from the outside to the first top electrode and the second top electrode via the drive pattern.

2. The bidirectional switch circuit according to claim 1, wherein the first top electrode and the second top electrode are electrically connected by the connection portion.

3. The bidirectional switch circuit according to claim 1, wherein the first anode electrode and the second anode electrode are electrically connected by the connection portion.

4. The bidirectional switch circuit according to claim 1, wherein the first top electrode and the first anode electrode are electrically connected by the connection portion.

5. The bidirectional switch circuit according to claim 1, wherein the second upper electrode and the second anode electrode are electrically connected by the connection portion.

6. The bidirectional switch circuit according to any one of claims 1 to 5, wherein the first semiconductor device and the first diode are formed on one chip.

7. The bidirectional switch circuit according to any one of claims 1 to 6, wherein the first semiconductor device and the second semiconductor device are IGBTs.

8. The bidirectional switch circuit according to any one of claims 1 to 6, wherein the first semiconductor device and the second semiconductor device are MOSFETs.

9. A first pattern, a second pattern, a first gate electrode, a first back electrode, and a first upper electrode provided on the opposite side of the first back electrode, and a first semiconductor device having the first back electrode provided on the first pattern and electrically connected to the first pattern; a second gate electrode, a second back electrode, and a second upper electrode provided on the opposite side of the second back electrode, and a second semiconductor device having the second back electrode provided on the second pattern and electrically connected to the second pattern; a first cathode electrode and a first anode electrode provided on the opposite side of the first cathode electrode, and a first diode having the first cathode electrode provided on the first pattern and electrically connected to the first pattern; a second cathode electrode and a second anode electrode provided on the opposite side of the second cathode electrode, and a second diode having the second cathode electrode provided on the second pattern and electrically connected to the second pattern; a first wiring for electrically connecting the first upper electrode and the second anode electrode; a second wiring for electrically connecting the second upper electrode and the first anode electrode; comprising the first upper electrode, the second upper electrode, the first anode electrode, and the second anode electrode are electrically connected to each other; the first upper electrode and the second upper electrode, the first anode electrode and the second anode electrode, the first upper electrode and the first anode electrode, or the second upper electrode and the second anode electrode are electrically connected by a connection portion; the connection portion is provided separately from the first wiring and the second wiring A bidirectional switch circuit, wherein a member connecting the first top electrode, the second top electrode, the first anode electrode, and the second anode electrode to each other includes a fine metal wire.

10. The bidirectional switch circuit according to claim 9, wherein the fine metal wire is formed of copper, an Al alloy, or Al coated with copper.

11. The bidirectional switch circuit according to any one of claims 1 to 8, wherein a member connecting the first top electrode, the second top electrode, the first anode electrode, and the second anode electrode to each other includes a metal plate.

12. The bidirectional switch circuit according to any one of claims 1 to 11, wherein the first semiconductor device, the second semiconductor device, the first diode, or the second diode is formed of a wide bandgap semiconductor.

13. The bidirectional switch circuit according to claim 12, wherein the wide bandgap semiconductor is silicon carbide, a gallium nitride-based material, or diamond.

14. A power conversion device, comprising the bidirectional switch circuit according to any one of claims 1 to 13.

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