Semiconductor device

Abstract

This semiconductor device comprises: at least one semiconductor element that has a pair of surfaces opposite from each other, includes a first main electrode on one surface of the pair of surfaces, and includes a second main electrode and a signal electrode on the other surface; a first conductor plate that is electrically connected to the first main electrode of the semiconductor element; a second conductor plate that is electrically connected to the second main electrode of the semiconductor element; a first signal terminal that is connected to the signal electrode by wire bonding; and a second signal terminal that outputs a voltage signal for detecting the potential of the second main electrode. The second conductor plate includes an auxiliary terminal connected to the second signal terminal.

Description

Semiconductor Devices

[0001] The present invention relates to a semiconductor device.

[0002] Conventionally, semiconductor devices that convert DC power to AC power by switching semiconductor elements have been widely used. In such semiconductor devices, a metal plate called a lead frame is typically bonded to the main electrodes (source and drain electrodes) of the semiconductor element, and signal electrodes (gate electrodes) of the semiconductor element are connected to corresponding signal terminals by metal wires such as aluminum. A drive signal (gate signal) is input to the signal electrodes of the semiconductor element via the signal terminals, controlling the switching operation of the semiconductor element and converting DC power to AC power.

[0003] Regarding the bonding of a semiconductor element and a lead frame in a semiconductor device, for example, Patent Document 1 is known. Patent Document 1 describes a technology for suppressing an increase in the resistance of a clip that connects a semiconductor element and a lead frame, which is caused by the skin effect, by providing one or more through holes in the clip.

[0004] Japanese Patent Application Publication No. 2013-51295

[0005] When a semiconductor element mounted on a semiconductor device performs a switching operation, the semiconductor element generates heat, causing the temperature of the semiconductor device to rise. The semiconductor element generates a large amount of heat, particularly in the area including the main electrode and its surroundings, and is prone to becoming hotter than other areas. Meanwhile, large temperature fluctuations in the signal electrode of the semiconductor element can cause thermal stress at the junction between the signal electrode and the metal wire, which can cause the metal wire to peel off, potentially interrupting the electrical connection between the signal electrode and the signal terminal and making the switching operation of the semiconductor element impossible. However, Patent Document 1 does not sufficiently consider this issue, leaving room for improvement in terms of improving the reliability of semiconductor devices.

[0006] The present invention has been made in view of the above-mentioned problems, and a main object of the present invention is to improve the reliability of semiconductor devices.

[0007] A semiconductor device according to the present invention comprises at least one semiconductor element having a pair of opposing surfaces, with a first main electrode on one of the pair of surfaces and a second main electrode and a signal electrode on the other surface, a first conductor plate electrically connected to the first main electrode of the semiconductor element, a second conductor plate electrically connected to the second main electrode of the semiconductor element, a first signal terminal connected to the signal electrode by wire bonding, and a second signal terminal that outputs a voltage signal for detecting the potential of the second main electrode, and the second conductor plate has an auxiliary terminal connected to the second signal terminal.

[0008] According to the present invention, the reliability of the semiconductor device can be improved.

[0009] 1 is an overall perspective view of a semiconductor device according to an embodiment of the present invention; FIG. 2 is a diagram showing a circuit body according to an embodiment of the present invention; FIG. 3 is a perspective view of the circuit body when developed; FIG. 4 is a perspective view showing a semiconductor device with a thermally conductive sheet separated; FIG. 5 is a perspective view showing a semiconductor device with a thermally conductive sheet separated; FIG. 6 is a wiring diagram of a circuit body according to a first embodiment of the present invention; FIG. 7 is a wiring diagram of a circuit body according to a second embodiment of the present invention; FIG. 8 is a wiring diagram of a circuit body according to a third embodiment of the present invention; FIG. 9 is a wiring diagram of a circuit body according to a fourth embodiment of the present invention; and FIG.

[0010] Fig. 1 is an overall perspective view of a semiconductor device according to one embodiment of the present invention. The semiconductor device 100 shown in Fig. 1 has a semiconductor element therein, and converts DC power into AC power by switching the semiconductor element. The semiconductor device 100 is used, for example, in a power conversion device that converts DC power supplied from a high-voltage power supply into AC power to drive an AC motor. The semiconductor device 100 is also called a semiconductor module 100.

[0011] In the semiconductor device 100, an upper arm control terminal 102A, a P main terminal 102B, an N main terminal 103A, a lower arm control terminal 104A, and an AC main terminal 104B are each drawn out from a main portion sealed with a sealing resin 101. Thermally conductive sheets 105 are bonded to both side surfaces of the sealing resin 101.

[0012] For example, when the main part of the semiconductor device 100 is sealed with the sealing resin 101, the thermally conductive sheet 105 is integrally bonded to the sealing resin 101. Alternatively, after the main part of the semiconductor device 100 is sealed with the sealing resin 101, the thermally conductive sheet 105 may be adhered to both side surfaces of the sealing resin 101.

[0013] Fig. 2 is a diagram showing a circuit body 200 according to one embodiment of the present invention. The circuit body 200 shown in Fig. 2 is obtained by removing the sealing resin 101 and the thermally conductive sheet 105 from the semiconductor device 100. In other words, the semiconductor device 100 shown in Fig. 1 is formed by sealing the circuit body 200 shown in Fig. 2 except for a predetermined area from the tip of each terminal with the sealing resin 101 and joining or adhering the thermally conductive sheet 105.

[0014] The circuit body 200 has an upper arm first conductor plate 102, an upper arm second conductor plate 106, a third conductor plate 103, a lower arm first conductor plate 104, and a lower arm second conductor plate 107. The upper arm first conductor plate 102, the lower arm first conductor plate 104, and the third conductor plate 103 are each arranged on the same plane.

[0015] The upper arm first conductor plate 102 and the upper arm second conductor plate 106 are disposed opposite each other with the semiconductor element 109 sandwiched therebetween. The semiconductor element 109 and the upper arm first conductor plate 102, and the semiconductor element 109 and the upper arm second conductor plate 106 are electrically connected to each other by solder or the like. This forms an upper arm circuit body corresponding to the upper arm of the upper and lower arm circuits of the semiconductor device 100 for converting DC power to AC power.

[0016] 2, three semiconductor elements 109 are arranged in a row between the upper arm first conductor plate 102 and the upper arm second conductor plate 106, but the number of semiconductor elements 109 arranged is not limited to this. One or any number of semiconductor elements 109 may be arranged in a row and electrically connected to the upper arm first conductor plate 102 and the upper arm second conductor plate 106, respectively.

[0017] The lower arm of the upper and lower arm circuits of semiconductor device 100 has a structure similar to that of the upper arm. That is, lower arm first conductor plate 104 and lower arm second conductor plate 107 are arranged opposite each other with semiconductor element 109 (not shown) sandwiched therebetween. Semiconductor element 109 and lower arm first conductor plate 104, and semiconductor element 109 and lower arm second conductor plate 107 are electrically connected to each other by solder or the like. This forms a lower arm circuit body corresponding to the lower arm.

[0018] The semiconductor element 109 is, for example, a SiC chip. The semiconductor element 109 has a pair of opposing surfaces, with a first main electrode (drain electrode) on one surface and a second main electrode (source electrode) on the other surface. Each semiconductor element 109 in the upper arm circuit body is arranged with the first main electrode surface facing the upper arm first conductor plate 102 and the second main electrode surface facing the upper arm second conductor plate 106. The upper arm first conductor plate 102 and the first main electrode, and the upper arm second conductor plate 106 and the second main electrode are electrically connected by solder or the like. Similarly, each semiconductor element 109 in the lower arm circuit body is arranged with the first main electrode surface facing the lower arm first conductor plate 104 and the second main electrode surface facing the lower arm second conductor plate 107. The lower arm first conductor plate 104 and the first main electrode, and the lower arm second conductor plate 107 and the second main electrode are electrically connected by solder or the like.

[0019] The upper arm second conductor plate 106 has a joint 106A bent toward the lower arm first conductor plate 104, at a portion in the figure that is lower than the portion to which the second main electrode of the semiconductor element 109 is connected. The upper arm second conductor plate 106 is joined to the lower arm first conductor plate 104 at this joint 106A by solder or the like. This electrically connects the upper arm second conductor plate 106 and the lower arm first conductor plate 104.

[0020] Similarly, lower arm second conductor plate 107 has a joint 107A bent toward third conductor plate 103, formed in a portion in the figure that is above the portion to which the second main electrode of semiconductor element 109 is connected. Lower arm second conductor plate 107 is joined to third conductor plate 103 at joint 107A with solder or the like. This electrically connects lower arm second conductor plate 107 and third conductor plate 103.

[0021] In each of the upper arm circuit body and the lower arm circuit body, a temperature sensor 108 for detecting the temperature of the circuit body is disposed near the semiconductor element 109 of the upper arm first conductor plate 102 and near the semiconductor element 109 of the lower arm first conductor plate 104. Although temperature sensors 108 are disposed on both the upper arm first conductor plate 102 and the lower arm first conductor plate 104 in Fig. 2, a temperature sensor 108 may be disposed on only one of them.

[0022] Fig. 3 is an exploded perspective view of the circuit body 200. In Fig. 3, the surface opposite to that in Fig. 2, i.e., the surface on the side of the upper arm first conductor plate 102, the lower arm first conductor plate 104, and the third conductor plate 103, is shown on the near side, and the surface on the side of the upper arm second conductor plate 106 and the lower arm second conductor plate 107 is shown on the far side.

[0023] The upper arm first conductor plate 102 has a convex portion 102C that protrudes continuously in the left-right direction in the figure on the surface opposite to the surface to which the semiconductor element 109 is bonded. The third conductor plate 103 also has a convex portion 103C that is similar to the convex portion 102C of the upper arm first conductor plate 102 and aligned in the same direction. The upper arm first conductor plate 102 and the third conductor plate 103 are formed integrally, including the convex portions 102C and 103C, by, for example, drawing, rolling, or the like, and then separated from each other to form each of them.

[0024] Like the upper arm first conductor plate 102 and the third conductor plate 103, the lower arm first conductor plate 104 also has a convex portion 104C that protrudes continuously in a convex shape in the left-right direction in the figure on the surface opposite to the surface to which the semiconductor element 109 is joined.

[0025] In the upper arm first conductor plate 102, a thin portion 102D that is thinner than the convex portion 102C and the convex portion 104C is formed between the convex portion 102C and the lower arm first conductor plate 104. Similarly, in the lower arm first conductor plate 104, a thin portion 104D that is thinner than the convex portion 102C and the convex portion 104C is formed between the convex portion 104C and the upper arm first conductor plate 102. Furthermore, in the third conductor plate 103, a thin portion 103E that is thinner than the convex portion 103C and the convex portion 104C is formed between the convex portion 103C and the lower arm first conductor plate 104.

[0026] The lower arm first conductor plate 104 is formed, for example, integrally with the upper arm first conductor plate 102 and the third conductor plate 103, and then cut and separated from these. The convex portion 104C of the lower arm first conductor plate 104 is formed separately from these convex portions 102C and 103C before being separated from the upper arm first conductor plate 102 and the third conductor plate 103. However, the convex portion 104C and the convex portions 102C and 103C are arranged on the same plane in the circuit body 200.

[0027] The upper arm second conductor plate 106 is provided corresponding to each semiconductor element 109 and has one or more pedestal portions 106B electrically connected to the corresponding semiconductor element 109, and auxiliary terminals 106C. Similarly, the lower arm second conductor plate 107 is provided corresponding to each semiconductor element 109 and has one or more pedestal portions 107B electrically connected to the corresponding semiconductor element 109, and auxiliary terminals 107C. The auxiliary terminals 106C, 107C are formed on the upper arm second conductor plate 106 and the lower arm second conductor plate 107 as portions that protrude toward the opposite side from the aforementioned joints 106A, 107A in a direction (vertical direction in the figure) perpendicular to the arrangement direction of the semiconductor elements 109 (horizontal direction in the figure). The auxiliary terminals 106C, 107C will be described in detail later.

[0028] 4 is a perspective view showing a state in which the thermally conductive sheet 105 is separated from the semiconductor device 100. In FIG. 4, a sealing body 201 in which the circuit body 200 is sealed with the sealing resin 101, and a pair of thermally conductive sheets 105 are shown.

[0029] On the front surface of sealing body 201 in the figure, the aforementioned convex portions 102C, 103C, and 104C are exposed on the same plane as sealing resin 101. The exposed surfaces of convex portions 102C, 103C, and 104C and the surface of sealing resin 101 are each bonded in close contact with the same thermally conductive sheet 105.

[0030] Fig. 5 is a perspective view showing the semiconductor device 100 with the thermally conductive sheet 105 separated, showing the opposite side to that of Fig. 4. That is, the thermally conductive sheet 105 located on the front side (lower right side in the figure) in Fig. 4 is located on the rear side (upper left side in the figure) in Fig. 5, and conversely, the thermally conductive sheet 105 located on the rear side in Fig. 4 is located on the front side in Fig. 5.

[0031] In sealing body 201, on the front side in the figure, the surface opposite to base portion 106B of upper arm second conductor plate 106 and the surface opposite to base portion 107B of lower arm second conductor plate 107 are each exposed on the same plane as sealing resin 101. These exposed surfaces and the surface of sealing resin 101 are each bonded in close contact with the same thermally conductive sheet 105.

[0032] In the semiconductor device 100, with the structure described above, the semiconductor element 109 and the thermally conductive sheet 105 are thermally coupled via the convex portion 102C of the upper arm first conductor plate 102, the convex portion 104C of the lower arm first conductor plate 104, the upper arm second conductor plate 106, and the lower arm second conductor plate 107. This allows heat generated in the semiconductor element 109 to be dissipated to the outside through the thermally conductive sheet 105.

[0033] Next, a description will be given of the wiring structure of the circuit body 200 in the semiconductor device 100. In the semiconductor device 100 according to the present invention, there are various variations of the circuit body 200 with different wiring structures. Below, first to fifth embodiments are representative examples of variations of the circuit body 200, and the wiring structures of these embodiments will be described.

[0034] 6 is a wiring diagram of a circuit body 200 according to a first embodiment of the present invention. Fig. 6 shows a plan view of the circuit body 200 of this embodiment as viewed from the side of the upper arm second conductor plate 106 and the lower arm second conductor plate 107.

[0035] The upper arm control terminal 102A is composed of a first signal terminal 102F, a second signal terminal 102E, a third signal terminal 102G, and a pair of temperature signal terminals 102H. These terminals are arranged side by side in a first direction (the left-right direction in the figure), which is the same direction as the arrangement of the three semiconductor elements 109 of the upper arm.

[0036] The first signal terminal 102F is provided with a first connection portion 102L for connection to the semiconductor element 109, located adjacent to the upper arm first conductor plate 102. Wires 111 made of metal such as aluminum are bonded to this first connection portion 102L and to a signal electrode (gate pad) provided on the same surface as the second main electrode of each semiconductor element 109, thereby connecting them to each other by wire bonding. This electrically connects the first signal terminal 102F and the signal electrode of each semiconductor element 109.

[0037] The second signal terminal 102E is electrically connected at the second connection portion 102J to the auxiliary terminal 106C of the upper arm second conductor plate 106 by soldering or the like. As a result, a voltage signal corresponding to the potential of the second main electrode of each semiconductor element 109 is output to the second signal terminal 102E via the upper arm second conductor plate 106. A control device (not shown) that controls the operation of the semiconductor device 100 can detect the potential of the second main electrode of each semiconductor element 109 by detecting the voltage signal of the second signal terminal 102E.

[0038] The third signal terminal 102G is formed integrally with the upper arm first conductor plate 102, and a voltage signal corresponding to the potential of the first main electrode of each semiconductor element 109 is output to the third signal terminal 102G via the upper arm first conductor plate 102. A control device (not shown) that controls the operation of the semiconductor device 100 can detect the potential of the first main electrode of each semiconductor element 109 by detecting the voltage signal of the third signal terminal 102G. Note that the third signal terminal 102G and the upper arm first conductor plate 102 do not have to be formed integrally, but may be formed separately and electrically connected to each other.

[0039] The pair of temperature signal terminals 102H are connected to both ends of the temperature sensor 108 by wire bonding using wires 110 made of metal such as aluminum. As a result, a voltage between the two ends corresponding to the temperature detection value of the temperature sensor 108 is output as a voltage signal by the pair of temperature signal terminals 102H. A control device (not shown) that controls the operation of the semiconductor device 100 can detect the temperature of each semiconductor element 109 by detecting the voltage signal of the temperature signal terminals 102H.

[0040] In the first signal terminal 102F, the first connection portion 102L has a first bent portion 102K bent at a substantially right angle to the extension direction of the first signal terminal 102F (the up-down direction in the figure). This first bent portion 102K is provided between the second connection portion 102J of the second signal terminal 102E and the signal electrode (gate pad) of each semiconductor element 109, and extends in the first direction beyond the auxiliary terminal 106C of the upper arm second conductor plate 106. Furthermore, the auxiliary terminal 106C is disposed between a pair of semiconductor elements 109 located at both ends of the multiple semiconductor elements 109 (three in the example of FIG. 6 ) arranged side by side in the first direction.

[0041] In the circuit body 200 of this embodiment, in the upper arm circuit body, the positional relationship between the first connecting portion 102L (first bent portion 102K) and the auxiliary terminal 106C as described above allows the range of connection destinations of the wire 111 in the first connecting portion 102L to be expanded in the first direction, straddling the auxiliary terminal 106C. As a result, for any semiconductor element 109, wire bonding can be performed by connecting the signal electrode (gate pad) and the first connecting portion 102L with the wire 111 without straddling the auxiliary terminal 106C. In other words, it is possible to connect the first signal terminal 102F and each semiconductor element 109 by wire bonding, without the wire 111 interfering with the second connecting portion 102J, which is the connection portion between the second signal terminal 102E and the upper arm second conductor plate 106.

[0042] While the wiring structure of the upper arm circuit body has been described above, the same applies to the wiring structure of the lower arm circuit body. Specifically, the lower arm control terminal 104A is composed of a first signal terminal 104F, a second signal terminal 104E, a third signal terminal 104G, and a pair of temperature signal terminals 104H, which are arranged in the same direction (first direction) as the three semiconductor elements 109 of the lower arm. The first signal terminal 104F is provided with a first connection portion 104L for connection to the semiconductor elements 109, located adjacent to the lower arm first conductor plate 104. Wires 111 made of metal, such as aluminum, are bonded to the first connection portion 104L and to signal electrodes (gate pads) provided on the same side as the second main electrodes of each semiconductor element 109, thereby connecting them to each other by wire bonding. This electrically connects the first signal terminal 104F to the signal electrodes of each semiconductor element 109.

[0043] The second signal terminal 104E is electrically connected at the second connection portion 104J to the auxiliary terminal 107C of the lower arm second conductor plate 107 by soldering or the like. As a result, a voltage signal corresponding to the potential of the second main electrode of each semiconductor element 109 is output to the second signal terminal 104E via the lower arm second conductor plate 107.

[0044] The third signal terminal 104G is formed integrally with the lower arm first conductor plate 104, and a voltage signal corresponding to the potential of the first main electrode of each semiconductor element 109 is output to the third signal terminal 104G via the lower arm first conductor plate 104. Note that the third signal terminal 104G and the lower arm first conductor plate 104 do not have to be formed integrally, but may be formed separately and electrically connected to each other.

[0045] The pair of temperature signal terminals 104H are connected to both ends of the temperature sensor 108 by wire bonding using wires 110 made of metal such as aluminum.

[0046] In the first signal terminal 104F, the first connection portion 104L has a first bent portion 104K bent at a substantially right angle to the extension direction of the first signal terminal 104F (the up-down direction in the figure). This first bent portion 104K is provided between the second connection portion 104J of the second signal terminal 104E and the signal electrode (gate pad) of each semiconductor element 109, and extends in the first direction beyond the auxiliary terminal 107C of the lower arm second conductor plate 107. Furthermore, the auxiliary terminal 107C is disposed between a pair of semiconductor elements 109 located at both ends of the multiple semiconductor elements 109 (three in the example of FIG. 6 ) arranged side by side in the first direction.

[0047] In the circuit body 200 of this embodiment, in the lower arm circuit body, the positional relationship between the first connection portion 104L (first bent portion 104K) and the auxiliary terminal 107C as described above allows the range of connection destinations of the wire 111 at the first connection portion 104L to be expanded in the first direction, straddling the auxiliary terminal 107C. As a result, for any semiconductor element 109, wire bonding can be performed by connecting the signal electrode (gate pad) and the first connection portion 104L with the wire 111 without straddling the auxiliary terminal 107C. In other words, it is possible to connect the first signal terminal 104F and each semiconductor element 109 by wire bonding, without the wire 111 interfering with the second connection portion 104J, which is the connection portion between the second signal terminal 104E and the lower arm second conductor plate 107.

[0048] Second Embodiment Fig. 7 is a wiring diagram of a circuit body 200 according to a second embodiment of the present invention. Fig. 7 shows a plan view of the circuit body 200 of this embodiment as viewed from the side of the upper arm second conductor plate 106 and the lower arm second conductor plate 107.

[0049] In this embodiment, an example will be described in which the shapes of the first signal terminals 102F, 104F and the second signal terminals 102E, 104E are different from those of the first embodiment described in Fig. 6. For example, this embodiment can be used when it is desired to shorten the lengths of the auxiliary terminals 106C, 107C in Fig. 6 in the upper arm second conductor plate 106 and the lower arm second conductor plate 107 due to material availability during production. Note that a description of the same parts as in the first embodiment will be omitted unless particularly necessary.

[0050] In this embodiment, the first signal terminal 102F is provided with a first connection portion 102M for connection to the semiconductor element 109, instead of the first connection portion 102L of Fig. 6. Wires 111 made of metal such as aluminum are bonded to the first connection portion 102M and the signal electrode (gate pad) of each semiconductor element 109, thereby connecting them to each other by wire bonding. This electrically connects the first signal terminal 102F and the signal electrode of each semiconductor element 109.

[0051] In this embodiment, the second signal terminal 102E has a second connection portion 102N instead of the second connection portion 102J in Fig. 6, and this second connection portion 102N is electrically connected by soldering or the like to the auxiliary terminal 106D of the upper arm second conductor plate 106. The auxiliary terminal 106D is provided on the upper arm second conductor plate 106 instead of the auxiliary terminal 106C in Fig. 6, and is shorter in length than the auxiliary terminal 106C.

[0052] In the second signal terminal 102E, the second connection portion 102N has a second bent portion 102P bent at a substantially right angle to the extension direction of the second signal terminal 102E (the up-down direction in the figure). The second bent portion 102P is provided between the first connection portion 102M of the first signal terminal 102F and the signal electrode (gate pad) of each semiconductor element 109, and extends beyond the auxiliary terminal 106D of the upper arm second conductor plate 106 in the first direction.

[0053] In the circuit body 200 of this embodiment, the connection position of the second signal terminal 102E and the auxiliary terminal 106D in the upper arm circuit body can be adjusted to any position along the first direction due to the arrangement relationship of the first connection portion 102M, the second connection portion 102N (second bent portion 102P), and the auxiliary terminal 106D as described above. As a result, the connection position of the second signal terminal 102E and the auxiliary terminal 106D can be determined so that, for any semiconductor element 109, wire bonding can be performed by connecting the signal electrode (gate pad) and the first connection portion 102M with the wire 111 without crossing the auxiliary terminal 106D. That is, as in the first embodiment, the first signal terminal 102F can be connected to each semiconductor element 109 by wire bonding without the wire 111 interfering with the second connection portion 102N, which is the connection portion of the second signal terminal 102E and the upper arm second conductor plate 106.

[0054] While the wiring structure of the upper arm circuit body has been described above, the same applies to the wiring structure of the lower arm circuit body. That is, instead of the first connection portion 104L shown in Fig. 6, the first signal terminal 104F is provided with a first connection portion 104M for connection to the semiconductor element 109, and wires 111 made of metal such as aluminum are joined to this first connection portion 104M and to the signal electrodes (gate pads) of each semiconductor element 109, thereby connecting them to each other by wire bonding. This electrically connects the first signal terminal 104F to the signal electrodes of each semiconductor element 109.

[0055] The second signal terminal 104E has a second connection portion 104N instead of the second connection portion 104J in Fig. 6, and this second connection portion 104N is electrically connected by soldering or the like to an auxiliary terminal 107D of the lower arm second conductor plate 107. The auxiliary terminal 107D is provided on the lower arm second conductor plate 107 instead of the auxiliary terminal 107C in Fig. 6, and is shorter in length than the auxiliary terminal 107C.

[0056] In the second signal terminal 104E, the second connection portion 104N has a second bent portion 104P bent at a substantially right angle to the extension direction of the second signal terminal 104E (the up-down direction in the figure). This second bent portion 104P is provided between the first connection portion 104M of the first signal terminal 104F and the signal electrode (gate pad) of each semiconductor element 109, and extends beyond the auxiliary terminal 107D of the lower arm second conductor plate 107 in the first direction.

[0057] In the circuit body 200 of this embodiment, the connection position of the second signal terminal 104E and the auxiliary terminal 107D in the lower arm circuit body can be adjusted to any position along the first direction due to the arrangement relationship of the first connection portion 104M, the second connection portion 104N (second bent portion 104P), and the auxiliary terminal 107D as described above. As a result, the connection position of the second signal terminal 104E and the auxiliary terminal 107D can be determined so that, for any semiconductor element 109, wire bonding can be performed by connecting the signal electrode (gate pad) and the first connection portion 104M with the wire 111 without crossing the auxiliary terminal 107D. That is, as in the first embodiment, the first signal terminal 104F can be connected to each semiconductor element 109 by wire bonding without the wire 111 interfering with the second connection portion 104N, which is the connection portion of the second signal terminal 104E and the lower arm second conductor plate 107.

[0058] 8 is a wiring diagram of a circuit body 200 according to a third embodiment of the present invention. Fig. 8 shows a plan view of the circuit body 200 of this embodiment as viewed from the side of the upper arm second conductor plate 106 and the lower arm second conductor plate 107.

[0059] In this embodiment, an example will be described in which the shapes of the first signal terminals 102F, 104F and the third signal terminals 102G, 104G are different from those of the second embodiment described in Fig. 7. For example, this embodiment can be adopted when eliminating the difference in distance from the second main electrode of each semiconductor element 109 to the second signal terminals 102E, 104E to stabilize the electrical characteristics of each semiconductor element 109. Note that, unless particularly necessary, descriptions of parts similar to those of the second embodiment will be omitted.

[0060] In this embodiment, the third signal terminal 102G is branched from the upper arm first conductor plate 102 at a position closer to the tip end (the P main terminal 102B side) of the upper arm first conductor plate 102 than in the first and second embodiments. The first connection portion 102M of the first signal terminal 102F passes between the third signal terminal 102G and the second bent portion 102P of the second signal terminal 102E and extends close to the upper arm first conductor plate 102. Wires 111 made of metal such as aluminum are bonded to the first connection portion 102M and the signal electrodes (gate pads) of each semiconductor element 109, thereby connecting them to each other by wire bonding. This electrically connects the first signal terminal 102F to the signal electrodes of each semiconductor element 109.

[0061] In the present embodiment, the auxiliary terminals 106D are disposed at equal distances in the first direction from both ends of the upper arm second conductor plate 106. Accordingly, the second connection portion 102N in the present embodiment is located to the right in the drawing compared to the second embodiment.

[0062] In the circuit body 200 of this embodiment, the arrangement of the first connecting portion 102M, the second connecting portion 102N (second bent portion 102P), and the auxiliary terminal 106D in the upper arm circuit body as described above makes it possible to reduce the deviation between the voltage signal output from the second signal terminal 102E and the potential of the second main electrode of each semiconductor element 109 while avoiding interference between the second connecting portion 102N and the wire 111. This makes it possible to suppress ringing and the like caused by output deviations of each semiconductor element 109, thereby stabilizing the electrical characteristics. As a result, it becomes possible to prevent the semiconductor elements 109 from being turned on erroneously.

[0063] While the wiring structure of the upper arm circuit body has been described above, the wiring structure of the lower arm circuit body is similar. Specifically, the third signal terminal 104G is formed by branching off from the lower arm first conductor plate 104 at a position closer to the tip of the lower arm first conductor plate 104 (the AC main terminal 104B side). The first connection portion 104M of the first signal terminal 104F passes between the third signal terminal 104G and the second bent portion 104P of the second signal terminal 104E and extends to near the lower arm first conductor plate 104. Wires 111 made of metal, such as aluminum, are bonded to the first connection portion 104M and the signal electrodes (gate pads) of each semiconductor element 109, thereby connecting them to each other by wire bonding. This electrically connects the first signal terminal 102F to the signal electrodes of each semiconductor element 109. The auxiliary terminals 107D are arranged at equal distances from both ends of the lower arm second conductor plate 107 in the first direction.

[0064] In the circuit body 200 of this embodiment, the arrangement of the first connecting portion 104M, the second connecting portion 104N (second bent portion 104P), and the auxiliary terminal 107D in the lower arm circuit body as described above makes it possible to reduce the deviation between the voltage signal output from the second signal terminal 104E and the potential of the second main electrode of each semiconductor element 109 while avoiding interference between the second connecting portion 104N and the wire 111. This makes it possible to suppress ringing and the like caused by output deviations of each semiconductor element 109, thereby stabilizing the electrical characteristics. As a result, it becomes possible to prevent the semiconductor elements 109 from being turned on erroneously.

[0065] 9 is a wiring diagram of a circuit body 200 according to a fourth embodiment of the present invention. Fig. 9 shows a plan view of the circuit body 200 of this embodiment as viewed from the side of the upper arm second conductor plate 106 and the lower arm second conductor plate 107.

[0066] 7, this embodiment will describe an example in which a resin-coated temperature sensor 112 is used instead of the temperature sensor 108. Note that, unless particularly necessary, descriptions of the same parts as those in the second embodiment will be omitted.

[0067] Similar to the temperature sensor 108 described above, the temperature sensor 112 is disposed near the semiconductor element 109 on the upper arm first conductor plate 102 and near the semiconductor element 109 on the lower arm first conductor plate 104. The temperature sensor 112 is attached to the upper arm first conductor plate 102 or the lower arm first conductor plate 104 by adhesive, soldering, or the like. Although the temperature sensor 112 is disposed on both the upper arm first conductor plate 102 and the lower arm first conductor plate 104 in FIG. 9 , the temperature sensor 112 may be disposed on only one of them.

[0068] The temperature sensor 112 is coated with resin and includes a pair of signal terminals 112A. The signal terminals 112A are electrically joined to the temperature signal terminals 102H and 104H, respectively, by soldering, resistance welding, laser welding, or the like.

[0069] Fifth Embodiment Fig. 10 is a wiring diagram of a circuit body 200 according to a fifth embodiment of the present invention. Fig. 10 shows a plan view of the circuit body 200 of this embodiment as viewed from the side of the upper arm second conductor plate 106 and the lower arm second conductor plate 107.

[0070] 7, this embodiment will describe an example in which a temperature-sensitive diode built into a semiconductor element 109 is used instead of the temperature sensor 108. Note that, unless particularly necessary, descriptions of the same parts as those in the second embodiment will be omitted.

[0071] At least one semiconductor element 109 in each of the upper arm circuit body and the lower arm circuit body incorporates a temperature-sensing diode that detects its own temperature. This semiconductor element 109 has an output terminal of the temperature-sensing diode on the same surface as the second main electrode (source electrode) and the signal electrode (gate electrode). The output terminal of the temperature-sensing diode is electrically connected to temperature signal terminals 102H and 104H, respectively, by wire bonding using wires 113 made of metal such as aluminum. Note that in FIG. 9 , the upper arm circuit body and the lower arm circuit body are provided with temperature signal terminals 102H and 104H, respectively, and the output terminal of the temperature-sensing diode is connected to both of these terminals. However, it is also possible to provide only one of the temperature signal terminals 102H or 104H and connect the output terminal of the temperature-sensing diode to this terminal.

[0072] According to the embodiment of the present invention described above, the following advantageous effects are achieved.

[0073] (1) The semiconductor device 100 includes at least one semiconductor element 109, an upper arm first conductor plate 102 and a lower arm first conductor plate 104 electrically connected to a first main electrode of the semiconductor element 109, an upper arm second conductor plate 106 and a lower arm second conductor plate 107 electrically connected to a second main electrode of the semiconductor element 109, first signal terminals 102F and 104F connected to signal electrodes of the semiconductor element 109 by wire bonding, and second signal terminals 102E and 104E that output voltage signals for detecting the potential of the second main electrode of the semiconductor element 109. The semiconductor element 109 has a pair of opposing surfaces, one of which has a first main electrode and the other of which has a second main electrode and a signal electrode. The upper arm second conductor plate 106 and the lower arm second conductor plate 107 have auxiliary terminals 106C and 107C connected to the second signal terminals 102E and 104E, respectively. This makes it possible to improve the reliability of the connection between the second main electrode of the semiconductor element 109 and the second signal terminals 102E and 104E, and as a result, the reliability of the semiconductor device 100 can be improved.

[0074] (2) The semiconductor device 100 includes a plurality of semiconductor elements 109. The plurality of semiconductor elements 109 are arranged in a first direction, which is the same as the arrangement direction of the terminals constituting the upper arm control terminal 102A, and are electrically connected to the common upper arm second conductor plate 106 or lower arm second conductor plate 107 for each arm. This configuration allows the second main electrodes of the plurality of semiconductor elements 109 to be simply connected to the second signal terminals 102E and 104E. Furthermore, the risk of short-circuiting the connection paths between the second main electrodes and the second signal terminals 102E and 104E can be reduced for the wires 111 connecting the signal electrodes of each semiconductor element 109 to the first signal terminals 102F and 104F.

[0075] (3) The semiconductor device 100 further includes a third conductor plate 103. The semiconductor elements 109 respectively constitute the upper and lower arms of the upper and lower arm circuits. The upper arm semiconductor element 109 is sandwiched between the upper arm first conductor plate 102 and the upper arm second conductor plate 106 to constitute the upper arm circuit body, while the lower arm semiconductor element 109 is sandwiched between the lower arm first conductor plate 104 and the lower arm second conductor plate 107 to constitute the lower arm circuit body. The upper arm second conductor plate 106 of the upper arm circuit body has a joint 106A joined to the lower arm first conductor plate 104 of the lower arm circuit body on the side opposite to the side on which the auxiliary terminal 106C is provided. Furthermore, the lower arm second conductor plate 107 of the lower arm circuit body has a joint 107A joined to the third conductor plate 103 on the side opposite to the side on which the auxiliary terminal 107C is provided. This facilitates the layout of auxiliary terminals 106C, 107C and enables miniaturization in upper arm second conductor plate 106 and lower arm second conductor plate 107. Furthermore, when upper arm second conductor plate 106 and lower arm second conductor plate 107 are joined to semiconductor element 109, upper arm second conductor plate 106 and lower arm second conductor plate 107 can be pressed down on both the auxiliary terminals 106C, 107C side and the joints 106A, 107A side, thereby preventing tilting of these conductor plates.

[0076] The present invention is not limited to the above-described embodiments and includes various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to those including all of the described configurations. Furthermore, it is possible to replace part of the configuration of one embodiment with the configuration of another embodiment, or to add the configuration of another embodiment to the configuration of one embodiment. Furthermore, it is possible to add, delete, or replace part of the configuration of each embodiment with other configurations.

[0077] The present invention is not limited to the above-described embodiment, and various modifications are possible without departing from the spirit of the present invention.

[0078] 100: semiconductor device, 101: sealing resin, 102: upper arm first conductor plate, 102A: upper arm control terminal, 102B: P main terminal, 102C: convex portion, 102D: thin portion, 102E: second signal terminal, 102F: first signal terminal, 102G: third signal terminal, 102H: temperature signal terminal, 102J, 102N: second connection portion, 102K: first bent portion, 102L, 102M: first connection portion, 102P: second bent portion, 103: third conductor plate, 103A: N main terminal, 103C: convex portion, 103E: thin portion, 104: lower arm first conductor plate, 104A: lower arm control terminal, 104B: AC main terminal, 104C: convex portion portion, 104D: thin portion, 104E: second signal terminal, 104F: first signal terminal, 104G: third signal terminal, 104H: temperature signal terminal, 104J, 104N: second connecting portion, 104K: first bent portion, 104L, 104M: first connecting portion, 104P: second bent portion, 105: thermally conductive sheet, 106: upper arm second conductor plate, 106A: joint portion, 106B: base portion, 106C, 106D: auxiliary terminal, 107: lower arm second conductor plate, 107A: joint portion, 107B: base portion, 107C, 107D: auxiliary terminal, 108, 112: temperature sensor, 109: semiconductor element, 110, 111: wire, 200: circuit body

Claims

1. A semiconductor device comprising: at least one semiconductor element having a pair of opposing surfaces, with a first main electrode on one of the pair of surfaces and a second main electrode and a signal electrode on the other surface; a first conductor plate electrically connected to the first main electrode of the semiconductor element; a second conductor plate electrically connected to the second main electrode of the semiconductor element; a first signal terminal connected to the signal electrode by wire bonding; and a second signal terminal for outputting a voltage signal for detecting the potential of the second main electrode, wherein the second conductor plate has an auxiliary terminal connected to the second signal terminal.

2. The semiconductor device according to claim 1, comprising a plurality of the semiconductor elements, the plurality of semiconductor elements being arranged side by side in a first direction and each electrically connected to the common second conductor plate.

3. The semiconductor device according to claim 2, wherein the first signal terminal and the second signal terminal are arranged side by side in the first direction, the first signal terminal has a first connection portion connected to the wire bonding, the second signal terminal has a second connection portion connected to the auxiliary terminal of the second conductor plate, the first connection portion has a first bent portion provided between the second connection portion and the signal electrode, the auxiliary terminal is arranged between a pair of semiconductor elements located at both ends of the plurality of semiconductor elements arranged side by side in the first direction, and the first bent portion extends in the first direction beyond the auxiliary terminal.

4. The semiconductor device according to claim 2, wherein the first signal terminal has a first connection portion connected to the wire bonding, the second signal terminal has a second connection portion connected to the auxiliary terminal of the second conductor plate, and the second connection portion has a second bent portion provided between the first connection portion and the signal electrode.

5. The semiconductor device according to any one of claims 2 to 4, wherein the auxiliary terminals are arranged at equal distances from both ends of the second conductive plate in the first direction.

6. The semiconductor device according to claim 1, further comprising a third conductor plate, wherein the semiconductor elements include a first semiconductor element and a second semiconductor element constituting an upper arm and a lower arm of an upper and lower arm circuit, respectively, wherein the first semiconductor element is sandwiched between the first conductor plate and the second conductor plate to constitute an upper arm circuit body, and the second semiconductor element is sandwiched between the first conductor plate and the second conductor plate to constitute a lower arm circuit body, wherein the second conductor plate of the upper arm circuit body has a first joint portion joined to the first conductor plate of the lower arm circuit body on the side opposite to the side on which the auxiliary terminal is provided, and wherein the second conductor plate of the lower arm circuit body has a second joint portion joined to the third conductor plate on the side opposite to the side on which the auxiliary terminal is provided.

7. The semiconductor device according to claim 1, further comprising: a temperature sensor; and a temperature signal terminal connected to said temperature sensor by wire bonding.

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