Semiconductor equipment

Abstract

This semiconductor equipment comprises: a first semiconductor device; a second semiconductor device; and a first circuit and a second circuit that have mutually different potentials. The second semiconductor device is electrically connected to the first semiconductor device, relays mutual signals between the first circuit and the second circuit, and isolates the first circuit and the second circuit from each other. The semiconductor equipment also comprises: a first terminal lead electrically connected to the first semiconductor device; a first wire connected to the first semiconductor device and to the second semiconductor device; and a second wire connected to the first semiconductor device and to the first terminal lead. The first wire includes a first metal. The second wire includes: a first core part that includes a second metal; and a first surface layer part that includes a third metal and that covers the first core part. The atomic number of the second metal is smaller than that of the first metal. The third metal exhibits a greater bonding strength relative to the first terminal lead than the second metal.

Description

Technical Field

[0001] The present disclosure relates to a semiconductor device, and more particularly to a semiconductor device that performs signal transmission via an insulating element between a plurality of semiconductor elements mounted in one package.

Background Art

[0002] Conventionally, an inverter device has been used in an electric vehicle (including a hybrid vehicle) or home appliances. Also, various semiconductor devices are used in the inverter device. For example, the inverter device includes a semiconductor device for control / driving and a semiconductor device for switching (a switching element such as an IGBT (Insulated Gate Bipolar Transistor) or a MOSFET (Metal Oxide Semiconductor Field Effect Transistor)). The former semiconductor device has a controller and a gate driver. In the inverter device, a control signal output from an ECU (Engine Control Unit) is input to the controller of the semiconductor device. The controller converts the control signal into a PWM (Pulse Width Modulation) control signal and transmits it to the gate driver. The gate driver drives a plurality (for example, six) of switching elements at a desired timing based on the PWM control signal. Thereby, three-phase AC power for motor driving is generated from the DC power of the in-vehicle battery. For example, Patent Document 1 discloses an example of a semiconductor device (drive circuit) used in a motor drive device.

[0003] In the conventional semiconductor devices described above, the power supply voltage required for the controller and the power supply voltage required for the gate driver may differ. In such cases, in a semiconductor device that incorporates multiple semiconductor elements in a single package, a difference in the applied power supply voltage occurs between the two conductive paths: the conductive path to the controller and the conductive path to the gate driver. For this reason, insulating elements are sometimes incorporated to act as intermediaries between these conductive paths. However, a problem arises in that the dielectric strength of wires connected to insulating elements decreases significantly when they come into close proximity to the insulating element. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2014-30049 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] In light of the circumstances described above, one of the objectives of this disclosure is to provide a semiconductor device that can reduce the cost of the device while ensuring the required dielectric strength. [Means for solving the problem]

[0006] The semiconductor device provided by this disclosure comprises a first semiconductor element, a first circuit and a second circuit having different potentials from each other, a second semiconductor element that conducts to the first semiconductor element, relays mutual signals between the first circuit and the second circuit, and insulates the first circuit and the second circuit from each other, a first terminal lead that conducts to the first semiconductor element, a first wire connected to the first semiconductor element and the second semiconductor element, and a second wire connected to the first semiconductor element and the first terminal lead. The first wire contains a first metal. The second wire contains a first core material portion containing a second metal, and a first surface layer portion containing a third metal and covering the first core material portion. The atomic number of the second metal is smaller than the atomic number of the first metal. The bonding strength with the first terminal lead is higher with the third metal than with the second metal. [Effects of the Invention]

[0007] According to the above configuration, it becomes possible to reduce the cost of the semiconductor device while ensuring the required dielectric strength.

[0008] Other features and advantages of this disclosure will become more apparent from the detailed description below, based on the accompanying drawings. [Brief explanation of the drawing]

[0009] [Figure 1] This is a plan view of a semiconductor device according to a first embodiment of the present disclosure. [Figure 2] This is a plan view corresponding to Figure 1, and it shows the encapsulating resin. [Figure 3] Figure 1 is a front view of the semiconductor device shown. [Figure 4] Figure 1 is a left side view of the semiconductor device shown. [Figure 5] Figure 1 is a right side view of the semiconductor device shown. [Figure 6] This is a cross-sectional view along the line VI-VI in Figure 2. [Figure 7] This is a cross-sectional view along the line VII-VII in Figure 2. [Figure 8]This is a partially enlarged cross-sectional view of Figure 6. [Figure 9] This is a partially enlarged cross-sectional view of Figure 6. [Figure 10] This is a partially enlarged cross-sectional view of Figure 6. [Figure 11] This is a partially enlarged cross-sectional view of Figure 6. [Figure 12] This is a plan view of a semiconductor device according to a second embodiment of the present disclosure, which is permeable to the sealing resin. [Figure 13] Figure 12 is a partially enlarged cross-sectional view of the semiconductor device shown. [Figure 14] Figure 12 is a partially enlarged cross-sectional view of the semiconductor device shown. [Figure 15] This is a plan view of a semiconductor device according to a third embodiment of the present disclosure, and shows a transparent encapsulating resin. [Figure 16] This is a cross-sectional view along the line XVI-XVI in Figure 15. [Modes for carrying out the invention]

[0010] The forms for implementing this disclosure will be described based on the attached drawings.

[0011] A semiconductor device A1 according to a first embodiment of this disclosure will be described based on Figures 1 to 11. The semiconductor device A1 comprises a first semiconductor element 11, a second semiconductor element 12, a third semiconductor element 13, a first island lead 21, a second island lead 22, a plurality of first terminal leads 31, a plurality of second terminal leads 32, and a sealing resin 50. Furthermore, the semiconductor device A1 comprises a plurality of first wires 41, a plurality of second wires 42, a plurality of third wires 43, a plurality of fourth wires 44, a plurality of fifth wires 45, and a plurality of sixth wires 46. The semiconductor device A1 is surface-mounted on a wiring board of an inverter device such as an electric vehicle (including a hybrid vehicle). The package format of the semiconductor device A1 is SOP (Small Outline Package). However, the package format of the semiconductor device A1 is not limited to SOP. Figure 2 shows the sealing resin 50 through which dashed lines (double dotted lines) are visible.

[0012] In the description of the semiconductor device A1, the thickness direction of each of the first semiconductor element 11, the second semiconductor element 12, the third semiconductor element 13, the first island lead 21, the second island lead 22, the plurality of first terminal leads 31, and the plurality of second terminal leads 32 is referred to as the "thickness direction z". Two directions that are orthogonal to the thickness direction z and orthogonal to each other are referred to as the first direction and the second direction. In the drawings, for example, the x direction is an example of the first direction, and the y direction is an example of the second direction, but the present disclosure is not limited thereto.

[0013] The first semiconductor element 11, the second semiconductor element 12, and the third semiconductor element 13 are elements that are the functional centers of the semiconductor device A1. In the semiconductor device A1, the first semiconductor element 11, the second semiconductor element 12, and the third semiconductor element 13 are each composed of individual elements. In the first direction x, the third semiconductor element 13 is located on the opposite side of the first semiconductor element 11 with respect to the second semiconductor element 12. Viewed in the thickness direction z, each of the first semiconductor element 11, the second semiconductor element 12, and the third semiconductor element 13 is rectangular with the second direction y as the long side.

[0014] The first semiconductor element 11 is a controller (control element) of a gate driver that drives a switching element such as an IGBT or a MOSFET. The first semiconductor element 11 includes a circuit that converts a control signal input from an ECU or the like into a PWM control signal, a transmission circuit for transmitting the PWM control signal to the third semiconductor element 13, and a reception circuit for receiving an electrical signal from the third semiconductor element 13.

[0015] The third semiconductor element 13 is a gate driver (drive element) for driving a switching element. The third semiconductor element 13 includes a reception circuit for receiving a PWM control signal, a circuit for driving a switching element based on the PWM control signal, and a transmission circuit for transmitting an electrical signal to the first semiconductor element 11. The electrical signal includes, for example, an output signal from a temperature sensor disposed near the motor.

[0016] The second semiconductor element 12 is an element for transmitting PWM control signals and other electrical signals in an isolated state. In semiconductor device A1, the second semiconductor element 12 is an inductive type. An example of an inductive type second semiconductor element 12 is an isolated transformer. An isolated transformer transmits electrical signals in an isolated state by inductively coupling two inductors (coils). The second semiconductor element 12 has a substrate made of silicon. An inductor made of copper (Cu) is formed on the substrate. The inductor includes a transmitting inductor and a receiving inductor, and these inductors are stacked in the thickness direction z. A dielectric layer made of silicon dioxide (SiO2) or the like is interposed between the transmitting inductor and the receiving inductor. The transmitting inductor and the receiving inductor are electrically insulated by this dielectric layer. In addition, the second semiconductor element 12 may be a capacitive type. An example of a capacitive type second semiconductor element 12 is a capacitor. Furthermore, the second semiconductor element 12 may be a photocoupler.

[0017] In semiconductor device A1, the third semiconductor element 13 requires a power supply voltage higher than that required for the first semiconductor element 11. Therefore, a significant potential difference arises between the first semiconductor element 11 and the third semiconductor element 13. To address this, in semiconductor device A1, a first circuit containing the first semiconductor element 11 and a second circuit containing the third semiconductor element 13 are insulated from each other by the second semiconductor element 12. The components of the first circuit include, in addition to the first semiconductor element 11, a first island lead 21, multiple first terminal leads 31, multiple first wires 41, multiple second wires 42, and multiple fifth wires 45. The components of the second circuit include, in addition to the third semiconductor element 13, a second island lead 22, multiple second terminal leads 32, multiple third wires 43, multiple fourth wires 44, and multiple sixth wires 46. The first and second circuits have relatively different potentials. In semiconductor device A1, the potential of the second circuit is higher than that of the first circuit. Furthermore, the second semiconductor element 12 relays the mutual signals between the first circuit and the second circuit. For example, in an inverter device for an electric vehicle, the voltage applied to the ground of the first semiconductor element 11 is approximately 0V, while the voltage applied to the ground of the third semiconductor element 13 may transiently exceed 600V.

[0018] As shown in Figures 2 and 5, the first semiconductor device 11 has a plurality of first metal layers 111. The plurality of first metal layers 111 are provided on the upper surface of the first semiconductor device 11 (the surface facing the same direction as the first mounting surface 211A of the first island portion 211 of the first island lead 21, which will be described later). The composition of the plurality of first metal layers 111 includes, for example, aluminum (Al) (i.e., each first metal layer 111 contains aluminum).

[0019] As shown in Figure 8, the first semiconductor device 11 further comprises a device body 11A, a plurality of second metal layers 112, a plurality of vias 113, a plurality of interlayer insulating films 114, a passivation film 115, and a surface protective film 116. The device body 11A includes a semiconductor substrate and a semiconductor layer. The plurality of second metal layers 112 overlap any of the plurality of first metal layers 111 when viewed in the thickness direction z, and are located inward in the thickness direction z of the first semiconductor device 11. The composition of the plurality of second metal layers 112 is, for example, aluminum. The bending stiffness of the first metal layer 111 is greater than the bending stiffness of the second metal layer 112. This difference in bending stiffness is due to the fact that the thickness t1 of the first metal layer 111 is greater than the thickness t2 of the second metal layer 112. The thickness t1 is between 1.5 μm and 10 μm. The plurality of first metal layers 111 correspond to the electrodes of the first semiconductor device 11. Multiple second metal layers 112 correspond to the redistribution layers of the first semiconductor device 11. Multiple vias 113, together with the multiple second metal layers 112, form conductive paths between the device body 11A and the multiple first metal layers 111. Multiple interlayer insulating films 114 are laminated on top of the device body 11A. Multiple second metal layers 112 and multiple vias 113 are covered by the multiple interlayer insulating films 114. Multiple interlayer insulating films 114 are made of, for example, silicon dioxide. Passivation films 115 are laminated on top of the multiple interlayer insulating films 114 and cover a portion of each of the multiple first metal layers 111. Passivation films 115 are made of, for example, silicon dioxide and silicon nitride (Si3N4). Surface protective films 116 are laminated on top of the passivation films 115. Multiple first metal layers 111 are exposed from the surface protective films 116. The surface protective film 116 is made of, for example, polyimide.

[0020] As shown in Figures 2 and 5, the second semiconductor element 12 is located between the first semiconductor element 11 and the third semiconductor element 13 in the first direction x. The upper surface of the second semiconductor element 12 (the surface facing the same direction as the first mounting surface 211A described above) is provided with a plurality of first electrodes 121 and a plurality of second electrodes 122. Each of the plurality of first electrodes 121 and the plurality of second electrodes 122 conducts to either the transmitting inductor or the receiving inductor. The plurality of first electrodes 121 are arranged along the second direction y and are located closer to the first semiconductor element 11 than to the third semiconductor element 13 in the first direction x. The plurality of second electrodes 122 are arranged along the second direction y and are located closer to the third semiconductor element 13 than to the first semiconductor element 11 in the first direction x.

[0021] As shown in Figures 2 and 5, the third semiconductor element 13 has a plurality of third metal layers 131. The plurality of third metal layers 131 are provided on the upper surface of the third semiconductor element 13 (the surface facing the same direction as the second mounting surface 221A of the second island portion 221 of the second island lead 22, which will be described later). The composition of the plurality of third metal layers 131 includes, for example, aluminum.

[0022] As shown in Figure 10, the third semiconductor element 13 further comprises an element body 13A, a plurality of fourth metal layers 132, a plurality of vias 133, a plurality of interlayer insulating films 134, a passivation film 135, and a surface protective film 136. The element body 13A includes a semiconductor substrate and semiconductor layers. The plurality of fourth metal layers 132 overlap any of the plurality of third metal layers 131 when viewed in the thickness direction z, and are located inward in the thickness direction z of the third semiconductor element 13. The composition of the plurality of fourth metal layers 132 is, for example, aluminum. The bending stiffness of the third metal layer 131 is greater than that of the fourth metal layer 132. This difference in bending stiffness is due to the fact that the thickness t3 of the third metal layer 131 is greater than the thickness t4 of the fourth metal layer 132. The thickness t3 is between 1.5 μm and 10 μm. The plurality of third metal layers 131 correspond to the electrodes of the third semiconductor element 13. Multiple fourth metal layers 132 correspond to the redistribution layers of the third semiconductor element 13. Multiple vias 133, together with the multiple fourth metal layers 132, form conductive paths between the element body 13A and the multiple third metal layers 131. Multiple interlayer insulating films 134 are laminated on top of the element body 13A. Multiple fourth metal layers 132 and multiple vias 133 are covered by the multiple interlayer insulating films 134. The multiple interlayer insulating films 134 are made of, for example, silicon dioxide. A passivation film 135 is laminated on top of the multiple interlayer insulating films 134 and covers a portion of each of the multiple third metal layers 131. The passivation film 135 is made of, for example, silicon dioxide and silicon nitride. A surface protective film 136 is laminated on top of the passivation film 135. Multiple third metal layers 131 are exposed from the surface protective film 136. The surface protective film 136 is made of, for example, polyimide.

[0023] The first island lead 21, the second island lead 22, the multiple first terminal leads 31, and the multiple second terminal leads 32 are conductive members that constitute a conductive path between the first semiconductor element 11, the second semiconductor element 12, and the third semiconductor element 13 and the wiring board on which the semiconductor device A1 is mounted. These main parts are obtained from the same lead frame, which contains copper in its composition.

[0024] As shown in Figures 1 and 2, the first island lead 21 and the second island lead 22 are located apart from each other in the first direction x. In semiconductor device A1, the first semiconductor element 11 and the second semiconductor element 12 are mounted on the first island lead 21, and the third semiconductor element 13 is mounted on the second island lead 22.

[0025] As shown in Figure 2, the first island lead 21 has a first island portion 211 and two first terminal portions 212. As shown in Figures 6 and 7, the first island portion 211 has a first mounting surface 211A oriented in the thickness direction z. In the semiconductor device A1, the first semiconductor element 11 and the second semiconductor element 12 are mounted on the first mounting surface 211A. The first semiconductor element 11 and the second semiconductor element 12 are bonded to the first mounting surface 211A via a conductive bonding material (solder, metal paste, etc.) not shown. The first island portion 211 is covered with a sealing resin 50. The thickness of the first island portion 211 is, for example, 100 μm or more and 300 μm or less.

[0026] As shown in Figures 2 and 6, the first island portion 211 has a plurality of through holes 213 formed therein. Each of the plurality of through holes 213 penetrates the first island portion 211 in the thickness direction z and extends along the second direction y. Viewed in the thickness direction z, at least one of the plurality of through holes 213 is located between the first semiconductor element 11 and the second semiconductor element 12. The plurality of through holes 213 are arranged along the second direction y.

[0027] As shown in Figure 2, the two first terminal portions 212 extend from both sides of the first island portion 211 in the second direction y. The two first terminal portions 212 are located apart from each other in the second direction y. At least one of the two first terminal portions 212 is conductive to the ground of the first semiconductor element 11 via the fifth wire 45. Each of the two first terminal portions 212 has a covered portion 212A and an exposed portion 212B. The covered portion 212A is connected to the first island portion 211 and is covered by the sealing resin 50. The covered portion 212A has a metal layer 23 (see Figure 13). The metal layer 23 is located on one side of the covered portion 212A in the thickness direction z (the side facing the first mounting surface 211A of the first island portion 211). The metal layer 23 is in contact with the sealing resin 50. The composition of the metal layer 23 includes silver (Ag). The exposed portion 212B is connected to the covered portion 212A and is exposed from the sealing resin 50. Viewed in the thickness direction z, the exposed portion 212B extends along the first direction x. As shown in Figure 3, viewed in the second direction y, the exposed portion 212B is bent in a gull-wing shape. The surface of the exposed portion 212B may be plated with, for example, tin (Sn).

[0028] As shown in Figure 2, the second island lead 22 has a second island portion 221 and two second terminal portions 222. As shown in Figure 6, the second island portion 221 has a second mounting surface 221A oriented in the thickness direction z. In the semiconductor device A1, a third semiconductor element 13 is mounted on the second mounting surface 221A. The third semiconductor element 13 is bonded to the second mounting surface 221A via a conductive bonding material (solder, metal paste, etc.) not shown. The second island portion 221 is covered with a sealing resin 50. The thickness of the second island portion 221 is, for example, 100 μm or more and 300 μm or less.

[0029] As shown in Figure 2, the two second terminal portions 222 extend from both sides of the second island portion 221 in the second direction y. The two second terminal portions 222 are located apart from each other in the second direction y. At least one of the two second terminal portions 222 is conductive to the ground of the third semiconductor element 13 via the sixth wire 46. Each of the two second terminal portions 222 has a covered portion 222A and an exposed portion 222B. The covered portion 222A is connected to the second island portion 221 and is covered by the sealing resin 50. The covered portion 222A has a metal layer 23 (see Figure 14). The metal layer 23 is located on one side of the covered portion 222A in the thickness direction z (the side facing the second mounting surface 221A of the second island portion 221). The exposed portion 222B is connected to the covered portion 222A and is exposed from the sealing resin 50. Viewed in the thickness direction z, the exposed portion 222B extends along the first direction x. As shown in Figure 3, viewed in the second direction y, the exposed portion 222B is bent in a gull-wing shape. The surface of the exposed portion 222B may be coated with, for example, tin plating.

[0030] As shown in Figures 1 and 2, the multiple first terminal leads 31 are located in the first direction x opposite to the second island portion 221 of the second island lead 22 with respect to the first island portion 211 of the first island lead 21. The multiple first terminal leads 31 are arranged along the second direction y. At least one of the multiple first terminal leads 31 is conductive to the first semiconductor element 11 via the second wire 42. The multiple first terminal leads 31 include a multiple first intermediate leads 31A and two first side leads 31B. The two first side leads 31B are located on either side of the multiple first intermediate leads 31A in the second direction y. Each of the two first side leads 31B is located in the second direction y between one of the two first terminal portions 212 of the first island lead 21 and the first intermediate lead 31A that is closest to that first terminal portion 212.

[0031] As shown in Figures 2 and 6, each of the multiple first terminal leads 31 has a covering portion 311 and an exposed portion 312. The covering portion 311 is covered with a sealing resin 50. The dimension of the covering portion 311 of each of the two first side leads 31B in the first direction x is greater than the dimension of the covering portion 311 of each of the multiple first intermediate leads 31A in the first direction x. As shown in Figure 9, the covering portion 311 has a metal layer 33. The metal layer 33 is located on one side of the covering portion 311 in the thickness direction z (the side facing the first mounting surface 211A of the first island portion 211 of the first island lead 21). The metal layer 33 is in contact with the sealing resin 50. The composition of the metal layer 33 includes silver.

[0032] As shown in Figures 2 and 6, the exposed portion 312 is connected to the covered portion 311 and is exposed from the sealing resin 50. Viewed in the thickness direction z, the exposed portion 312 extends along the first direction x. Viewed in the second direction y, the exposed portion 312 is bent in a gull-wing shape. The shape of the exposed portion 312 is equal to the shape of the exposed portion 212B of each of the two first terminal portions 212 of the first island lead 21. The surface of the exposed portion 312 may be tin-plated, for example.

[0033] As shown in Figures 1 and 2, the multiple second terminal leads 32 are located on the opposite side of the multiple first terminal leads 31 from the first island portion 211 of the first island lead 21 in the first direction x. The multiple second terminal leads 32 are arranged along the second direction y. At least one of the multiple second terminal leads 32 is conductive to the third semiconductor element 13 via the fourth wire 44. The multiple second terminal leads 32 include a multiple second intermediate lead 32A and two second side leads 32B. The two second side leads 32B are located on either side of the multiple second intermediate leads 32A in the second direction y. In the second direction y, one of the two second terminal portions 222 of the second island lead 22 is located between one of the two second side leads 32B and the second intermediate lead 32A that is closest to that second side lead 32B.

[0034] As shown in Figures 2 and 6, each of the multiple second terminal leads 32 has a covering portion 321 and an exposed portion 322. The covering portion 321 is covered with a sealing resin 50. The dimension of the covering portion 321 of each of the two second side leads 32B in the first direction x is greater than the dimension of the covering portion 321 of each of the multiple second intermediate leads 32A in the first direction x. As shown in Figure 11, the covering portion 321 has a metal layer 33. The metal layer 33 is located on one side of the covering portion 321 in the thickness direction z (the side facing the second mounting surface 221A of the second island portion 221 of the second island lead 22). The metal layer 33 is in contact with the sealing resin 50.

[0035] As shown in Figures 2 and 6, the exposed portion 322 is connected to the covered portion 321 and is exposed from the sealing resin 50. Viewed in the thickness direction z, the exposed portion 322 extends along the first direction x. As shown in Figure 3, viewed in the second direction y, the exposed portion 322 is bent in a gull-wing shape. The shape of the exposed portion 322 is equal to the shape of the exposed portion 222B of each of the two second terminal portions 222 of the second island lead 22. The surface of the exposed portion 322 may be tin-plated, for example.

[0036] Multiple first wires 41, multiple second wires 42, multiple third wires 43, multiple fourth wires 44, multiple fifth wires 45, and multiple sixth wires 46, together with the first island lead 21, the second island lead 22, multiple first terminal leads 31, and multiple second terminal leads 32, constitute a conductive path for the first semiconductor element 11, the second semiconductor element 12, and the third semiconductor element 13 to perform predetermined functions.

[0037] Each of the multiple first wires 41 is connected to one of the multiple first electrodes 121 of the second semiconductor element 12 and one of the multiple first metal layers 111 of the first semiconductor element 11, as shown in Figures 2 and 6. This allows the first semiconductor element 11 and the second semiconductor element 12 to be electrically connected to each other. The multiple first wires 41 are arranged along the second direction y. The multiple first wires 41 contain a first metal, which is gold (Au).

[0038] Each of the plurality of second wires 42 is connected to one of the plurality of first metal layers 111 of the first semiconductor element 11 and to the covering portion 311 of one of the plurality of first terminal leads 31, as shown in Figures 2 and 6. As a result, at least one of the plurality of first terminal leads 31 is electrically connected to the first semiconductor element 11. As shown in Figures 8 and 9, each of the plurality of second wires 42 includes a first core material portion 42A and a first surface layer portion 42B covering the first core material portion 42A. The first core material portion 42A contains a second metal. The atomic number of the second metal is smaller than that of the first metal mentioned above. The second metal is copper. The first surface layer portion 42B contains a third metal. The first surface layer portion 42B is in contact with the first metal layer 111 and the metal layer 33 of the covering portion 311. The bonding strength with the first terminal leads 31 is higher with the third metal than with the second metal. The third metal is palladium (Pd).

[0039] As shown in Figure 9, each of the multiple second wires 42 has a first main portion 421 and a first end portion 422. The first end portion 422 is interposed between the first main portion 421 and the covering portion 311 of the first terminal lead 31. The first end portion 422 has a first tapered portion 422A. The first tapered portion 422A is adjacent to the first main portion 421, and its dimension d in the thickness direction z decreases as it moves away from the first main portion 421. The joining interface 311A ​​between the covering portion 311 and the second wire 42 straddles the first main portion 421 and the first end portion 422 when viewed in the thickness direction z. The first end portion 422 has a first tip portion 422B. The first tip portion 422B is connected to the first tapered portion 422A and protrudes from the first tapered portion 422A in the thickness direction z.

[0040] Each of the multiple third wires 43 is connected to one of the multiple second electrodes 122 of the second semiconductor element 12 and one of the multiple third metal layers 131 of the third semiconductor element 13, as shown in Figures 2 and 6. This allows the third semiconductor element 13 and the second semiconductor element 12 to be electrically connected to each other. The multiple third wires 43 are arranged along the second direction y. In semiconductor device A1, the multiple third wires 43 straddle the first island portion 211 of the first island lead 21 and the second island portion 221 of the second island lead 22. The multiple third wires 43 include a fourth metal, which is gold.

[0041] Each of the multiple fourth wires 44 is connected to one of the multiple third metal layers 131 of the third semiconductor element 13 and to the covering portion 321 of one of the multiple second terminal leads 32, as shown in Figures 2 and 6. As a result, at least one of the multiple second terminal leads 32 is electrically connected to the third semiconductor element 13. As shown in Figures 10 and 11, each of the multiple fourth wires 44 includes a second core material portion 44A and a second surface layer portion 44B covering the second core material portion 44A. The second core material portion 44A contains a fifth metal. The atomic number of the fifth metal is smaller than that of the fourth metal mentioned above. The fifth metal is copper. The second surface layer portion 44B contains a sixth metal. The second surface layer portion 44B is in contact with the third metal layer 131 and the metal layer 33 of the covering portion 321. The bonding strength with the second terminal leads 32 is higher with the sixth metal than with the fifth metal. The sixth metal is palladium.

[0042] As shown in Figure 11, each of the multiple fourth wires 44 has a second main portion 441 and a second end portion 442. The second end portion 442 is interposed between the second main portion 441 and the covering portion 321 of the second terminal lead 32. The second end portion 442 has a second tapered portion 442A. The second tapered portion 442A is adjacent to the second main portion 441, and its dimension d in the thickness direction z decreases as it moves away from the second main portion 441. The joint interface 321A between the covering portion 321 and the fourth wire 44 straddles the second main portion 441 and the second end portion 442 when viewed in the thickness direction z. The second end portion 442 has a second tip portion 442B. The second tip portion 442B is connected to the second tapered portion 442A and protrudes from the second tapered portion 442A in the thickness direction z.

[0043] Each of the multiple fifth wires 45 is connected to one of the multiple first metal layers 111 of the first semiconductor element 11 and to the covering portion 212A of one of the two first terminal portions 212 of the first island lead 21, as shown in Figure 2. As a result, at least one of the two first terminal portions 212 is electrically connected to the first semiconductor element 11.

[0044] Each of the multiple sixth wires 46 is connected to one of the multiple third metal layers 131 of the third semiconductor element 13 and to the covering portion 222A of one of the two second terminal portions 222 of the second island lead 22, as shown in Figure 2. As a result, at least one of the two second terminal portions 222 is electrically connected to the third semiconductor element 13.

[0045] As shown in Figure 1, the encapsulating resin 50 covers a portion of each of the first semiconductor element 11, the second semiconductor element 12, and the third semiconductor element 13, as well as the first island lead 21, the second island lead 22, the multiple first terminal leads 31, and the multiple second terminal leads 32. Furthermore, the encapsulating resin 50 covers the multiple first wires 41, the multiple second wires 42, the multiple third wires 43, the multiple fourth wires 44, the multiple fifth wires 45, and the multiple sixth wires 46. The encapsulating resin 50 has electrical insulating properties. The encapsulating resin 50 insulates the first island lead 21 and the second island lead 22 from each other. The encapsulating resin 50 is made of a material including, for example, a black epoxy resin. The sulfur content per unit mass of the encapsulating resin 50 is 300 μg / g or less. Viewed in the thickness direction z, the encapsulating resin 50 is rectangular in shape.

[0046] As shown in Figures 3 to 5, the sealing resin 50 has a top surface 51, a bottom surface 52, a pair of first side surfaces 53, and a pair of second side surfaces 54.

[0047] As shown in Figures 3 to 5, the top surface 51 and the bottom surface 52 are located apart from each other in the thickness direction z. The top surface 51 and the bottom surface 52 face opposite each other in the thickness direction z. Each of the top surface 51 and the bottom surface 52 is flat (or nearly flat).

[0048] As shown in Figures 3 to 5, the pair of first sides 53 are connected to the top surface 51 and the bottom surface 52, and are located apart from each other in the first direction x. From the first side 53 located on one side of the pair of first sides 53 in the first direction x, the exposed portions 212B of the two first terminal portions 212 of the first island lead 21 and the exposed portions 312 of the multiple first terminal leads 31 are exposed. From the first side 53 located on the other side of the pair of first sides 53 in the first direction x, the exposed portions 222B of the two second terminal portions 222 of the second island lead 22 and the exposed portions 322 of the multiple second terminal leads 32 are exposed.

[0049] As shown in Figures 3 to 5, each of the pair of first sides 53 includes a first upper section 531, a first lower section 532, and a first intermediate section 533. The first upper section 531 has one side in the thickness direction z connected to the top surface 51 and the other side in the thickness direction z connected to the first intermediate section 533. The first upper section 531 is inclined with respect to the top surface 51. The first lower section 532 has one side in the thickness direction z connected to the bottom surface 52 and the other side in the thickness direction z connected to the first intermediate section 533. The first lower section 532 is inclined with respect to the bottom surface 52. The first intermediate section 533 has one side in the thickness direction z connected to the first upper section 531 and the other side in the thickness direction z connected to the first lower section 532. The in-plane direction of the first intermediate section 533 is the thickness direction z and the second direction y. Viewed in the thickness direction z, the first intermediate portion 533 is located outward from the top surface 51 and the bottom surface 52. From the first intermediate portion 533 of the pair of first sides 53, the exposed portions 212B of the two first terminal portions 212 of the first island lead 21, the exposed portions 222B of the two second terminal portions 222 of the second island lead 22, the exposed portions 312 of the multiple first terminal leads 31, and the exposed portions 322 of the multiple second terminal leads 32 are exposed.

[0050] As shown in Figures 3 to 5, the pair of second sides 54 are connected to the top surface 51 and the bottom surface 52, and are located apart from each other in the second direction y. As shown in Figure 1, the first island lead 21, the second island lead 22, the multiple first terminal leads 31, and the multiple second terminal leads 32 are located apart from the pair of second sides 54.

[0051] As shown in Figures 3 to 5, each of the pair of second sides 54 includes a second upper 541, a second lower 542, and a second intermediate 543. The second upper 541 has one side in the thickness direction z connected to the top surface 51 and the other side in the thickness direction z connected to the second intermediate 543. The second upper 541 is inclined with respect to the top surface 51. The second lower 542 has one side in the thickness direction z connected to the bottom surface 52 and the other side in the thickness direction z connected to the second intermediate 543. The second lower 542 is inclined with respect to the bottom surface 52. The second intermediate 543 has one side in the thickness direction z connected to the second upper 541 and the other side in the thickness direction z connected to the second lower 542. The in-plane direction of the second intermediate 543 is the thickness direction z and the second direction y. Viewed in the thickness direction z, the second intermediate portion 543 is located outward from the top surface 51 and the bottom surface 52.

[0052] In the motor driver circuit of an inverter device, a half-bridge circuit is generally configured, including a low-side (low-potential side) switching element and a high-side (high-potential side) switching element. In the following explanation, we will assume that these switching elements are MOSFETs. Here, for the low-side switching element, the reference potential of the source of the switching element and the reference potential of the gate driver that drives the switching element are both ground. On the other hand, for the high-side switching element, the reference potential of the source of the switching element and the reference potential of the gate driver that drives the switching element are both equivalent to the potential at the output node of the half-bridge circuit. Since the potential at the output node changes depending on the operation of the high-side and low-side switching elements, the reference potential of the gate driver that drives the high-side switching element changes. When the high-side switching element is on, the reference potential is equivalent to the voltage applied to the drain of the high-side switching element (for example, 600V or higher). In semiconductor device A1, the ground of the first semiconductor element 11 and the ground of the third semiconductor element 13 are separated. Therefore, when semiconductor device A1 is used as a gate driver to drive the high-side switching element, a voltage equivalent to the voltage applied to the drain of the high-side switching element is transiently applied to the ground of the third semiconductor device 13.

[0053] Next, we will explain the effects and benefits of semiconductor device A1.

[0054] The semiconductor device A1 includes a first wire 41 connected to a first semiconductor element 11 and a second semiconductor element 12, and a second wire 42 connected to the first semiconductor element 11 and a first terminal lead 31. The first wire 41 contains a first metal. The second wire 42 contains a first core material portion 42A containing a second metal, and a first surface layer portion 42B containing a third metal and covering the first core material portion 42A. The atomic number of the second metal is smaller than that of the first metal. As a result, when X-rays are emitted from the semiconductor device A1, the second wire 42 is more easily penetrated by X-rays than the first wire 41, so an X-ray image of the first wire 41 can be obtained. Therefore, it is possible to confirm by X-ray inspection whether the shape and height of the first wire 41 contribute to ensuring the dielectric strength required for the semiconductor device A1. Furthermore, the bonding strength with the first terminal lead 31 is higher with the third metal than with the second metal. This reduces the cost of the second wire 42 while preventing deterioration of the connection between the second wire 42 and the first terminal lead 31 (such as the occurrence of cracks). As a result, semiconductor device A1 makes it possible to reduce the cost of the device while ensuring the required dielectric strength.

[0055] Preferably, the first metal is gold and the second metal is copper. This allows for precise setting of the shape and height of the first wire 41 to ensure the dielectric strength required for the semiconductor device A1, and efficiently reduces the cost of the second wire 42. Furthermore, it is preferable that the third metal is palladium. This increases the bonding area of ​​the first surface layer 42B of the second wire 42 to the first terminal lead 31, thereby improving the bonding strength of the second wire 42 to the first terminal lead 31.

[0056] Furthermore, the semiconductor device A1 includes a third wire 43 connected to the second semiconductor element 12 and the third semiconductor element 13, and a fourth wire 44 connected to the third semiconductor element 13 and the second terminal lead 32. The third wire 43 contains a fourth metal. The fourth wire 44 includes a second core material portion 44A containing a fifth metal, and a second surface layer portion 44B containing a sixth metal and covering the second core material portion 44A. The atomic number of the fifth metal is smaller than that of the fourth metal. Furthermore, the bonding strength with the second terminal lead 32 is higher with the sixth metal than with the fifth metal. Therefore, the same effects and advantages as those of the first wire 41 and second wire 42 described above can be obtained with the third wire 43 and the fourth wire 44. In this case, it is preferable that the fourth metal is gold and the fifth metal is copper. Furthermore, it is preferable that the sixth metal is palladium.

[0057] The second wire 42 has a first main portion 421 and a first end portion 422 located between the first main portion 421 and the first terminal lead 31. The first end portion 422 includes a first tapered portion 422A adjacent to the first main portion 421, the dimension d in the thickness direction z (see Figure 9) decreasing as it moves away from the first main portion 421. This facilitates the transmission of tensile stress generated in the first end portion 422 when joined with the first terminal lead 31, thereby reducing stress concentration in the first end portion 422. Furthermore, the joining interface 311A ​​between the first terminal lead 31 and the second wire 42, as shown in Figure 9, spans both the first main portion 421 and the first end portion 422 when viewed in the thickness direction z. As a result, the connection of the second wire 42 to the first terminal lead 31 is shared not only by the first end portion 422 but also by the first main portion 421, thereby more effectively reducing stress concentration at the first end portion 422.

[0058] The fourth wire 44 has a second main portion 441 and a second end portion 442 located between the second main portion 441 and the second terminal lead 32. The second end portion 442 includes a second tapered portion 442A adjacent to the second main portion 441, the dimension d in the thickness direction z (see Figure 11) decreasing as it moves away from the second main portion 441. Furthermore, the joining interface 321A between the second terminal lead 32 and the fourth wire 44 shown in Figure 11 spans both the second main portion 441 and the second end portion 442 when viewed in the thickness direction z. Therefore, the same effects and advantages as those of the relationship between the first terminal lead 31 and the second wire 42 described above can be obtained with respect to the relationship between the second terminal lead 32 and the fourth wire 44.

[0059] The first semiconductor element 11 has a first metal layer 111 to which the second wire 42 is connected, and a first electrode 121 that overlaps the first metal layer 111 in the thickness direction z and is located inward in the thickness direction z. The bending rigidity of the first metal layer 111 is higher than that of the second metal layer 112. This makes it possible to suppress the occurrence of cracks in the first metal layer 111 due to the impact transmitted from the second wire 42 to the first metal layer 111 when the second wire 42 is connected to the first metal layer 111.

[0060] The semiconductor device A1 further comprises a sealing resin 50 covering the first semiconductor element 11, the second semiconductor element 12, the first wire 41, and the second wire 42. The sulfur content per unit mass of the sealing resin 50 is 300 μg / g or less. Here, the first core material portion 42A of the second wire 42, which contains a second metal (copper), is covered by a first surface layer portion 42B containing a third metal (palladium), and is therefore relatively resistant to corrosion. Furthermore, by limiting the upper limit of the sulfur content per unit mass of the sealing resin 50, corrosion of the first core material portion 42A can be suppressed more effectively.

[0061] In semiconductor device A1, a portion of each of the first island lead 21, the second island lead 22, the multiple first terminal leads 31, and the multiple second terminal leads 32 is exposed from one of the pair of first side surfaces 53 of the sealing resin 50. In this case, the first island lead 21, the second island lead 22, the multiple first terminal leads 31, and the multiple metal layers 33 are located away from the pair of second side surfaces 54 of the sealing resin 50. Therefore, in semiconductor device A1, no metal members such as island supports are exposed from the pair of second side surfaces 54. Consequently, the dielectric strength of semiconductor device A1 can be improved.

[0062] In semiconductor device A1, the first island portion 211 of the first island lead 21, which has a larger area than the second island portion 221 of the second island lead 22, has multiple through holes 213 formed therein. This prevents poor filling of the sealing resin 50 when it is injected into the mold during its formation. Therefore, the occurrence of voids in the sealing resin 50 can be effectively suppressed. This contributes to suppressing a decrease in the dielectric breakdown voltage of semiconductor device A1.

[0063] A semiconductor device A2 according to a second embodiment of the present disclosure will be described based on Figures 12 to 14. In these figures, elements that are the same as or similar to those in the semiconductor device A1 described above are denoted by the same reference numerals, and redundant explanations are omitted. For ease of understanding, Figure 12 shows the sealing resin 50 transparent and is indicated by dashed lines.

[0064] The semiconductor device A2 differs from the aforementioned semiconductor device A1 in that it further comprises multiple metal blocks 47.

[0065] As shown in Figures 12 and 13, the multiple metal blocks 47 are individually joined to the multiple fifth wires 45. Each of the multiple fifth wires 45 includes a third core material portion 45A and a third surface layer portion 45B. The third core material portion 45A contains the aforementioned second metal (copper). The third surface layer portion 45B contains the aforementioned third metal (palladium) and covers the third core material portion 45A. Each of the multiple fifth wires 45 has a connector portion 451. The connector portion 451 is connected to the covering portion 212A of the two first terminal portions 212 of the first island lead 21. The covering portion 212A includes a metal layer 23. The composition of the metal layer 23 includes silver. The connector portion 451 is in contact with the metal layer 23.

[0066] As shown in Figure 13, each of the multiple metal blocks 47 includes a core material portion 47A and a surface layer portion 47B. The core material portion 47A includes the aforementioned second metal (copper). The surface layer portion 47B includes the aforementioned third metal (palladium) and covers the core material portion 47A. The multiple metal blocks 47 are joined on the connection portion 451 of the multiple fifth wires 45. The core material portion 47A and the surface layer portion 47B of the multiple metal blocks 47 are in contact with the third surface layer portion 45B of the multiple fifth wires 45.

[0067] As shown in Figures 12 and 14, the multiple metal blocks 47 are individually joined to the multiple sixth wires 46. Each of the multiple sixth wires 46 includes a fourth core material portion 46A and a fourth surface layer portion 46B. The fourth core material portion 46A includes the aforementioned fifth metal (copper). The fourth surface layer portion 46B includes the aforementioned sixth metal (palladium) and covers the fourth core material portion 46A. Each of the multiple sixth wires 46 has a connection portion 461. The connection portion 461 is connected to the covering portion 222A of the two second terminal portions 222 of the second island lead 22. The covering portion 222A includes a metal layer 23. The connection portion 461 is in contact with the metal layer 23.

[0068] As shown in Figure 14, multiple metal blocks 47 are joined on top of connection points 461 of multiple sixth wires 46. The core material portion 47A and surface portion 47B of the multiple metal blocks 47 are in contact with the fourth surface portion 46B of the multiple sixth wires 46.

[0069] Next, we will explain the effects and benefits of semiconductor device A2.

[0070] The semiconductor device A2 comprises a first wire 41 connected to a first semiconductor element 11 and a second semiconductor element 12, and a second wire 42 connected to the first semiconductor element 11 and a first terminal lead 31. The first wire 41 contains a first metal. The second wire 42 contains a first core material portion 42A containing a second metal, and a first surface layer portion 42B containing a third metal and covering the first core material portion 42A. The atomic number of the second metal is smaller than that of the first metal. Furthermore, the bonding strength with the first terminal lead 31 is higher with the third metal than with the second metal. Therefore, the semiconductor device A2 also makes it possible to reduce the cost of the device while ensuring the required dielectric strength. Furthermore, by adopting a configuration common to the semiconductor device A1, the semiconductor device A2 achieves the same effects as the semiconductor device A1.

[0071] The semiconductor device A2 includes a fifth wire 45 connected to the first semiconductor element 11 and the first terminal portion 212 of the first island lead 21. Furthermore, the semiconductor device A2 includes a metal block 47 bonded to the connection portion 451 of the fifth wire 45 to the first terminal portion 212. This improves the bonding strength of the fifth wire 45 to the first terminal portion 212, thereby suppressing the occurrence of cracks in the fifth wire 45. This contributes to suppressing the difference between the ground potential of the first semiconductor element 11 and the potential of the first terminal portion 212.

[0072] The semiconductor device A2 includes a sixth wire 46 connected to the third semiconductor element 13 and the second terminal portion 222 of the second island lead 22. Furthermore, the semiconductor device A2 includes a metal block 47 bonded to the connection portion 461 of the sixth wire 46 to the second terminal portion 222. This improves the bonding strength of the sixth wire 46 to the second terminal portion 222, thereby suppressing the occurrence of cracks in the sixth wire 46. This contributes to suppressing the difference between the ground potential of the third semiconductor element 13 and the potential of the second terminal portion 222. The potential of the second terminal portion 222 is equal to the potential of the electrode of the switching element to be driven by the semiconductor device A1. Therefore, since the potential of the second terminal portion 222 fluctuates over time, suppressing the difference between the ground potential of the third semiconductor element 13 and the potential of the second terminal portion 222 contributes to the stable driving of the switching element.

[0073] A semiconductor device A3 according to a third embodiment of the present disclosure will be described with reference to Figures 15 and 16. In these figures, elements that are the same as or similar to those in the semiconductor device A1 described above are denoted by the same reference numerals, and redundant explanations are omitted. Here, in Figure 15, for ease of understanding, the sealing resin 50 is transparent and shown by dashed lines.

[0074] In semiconductor device A3, the mounting configuration of the second semiconductor element 12 differs from that of semiconductor device A1 described above.

[0075] As shown in Figures 15 and 16, the second semiconductor element 12 is mounted on the second mounting surface 221A of the second island portion 221 of the second island lead 22. Therefore, in the semiconductor device A3, multiple first wires 41 span between the first island portion 211 of the first island lead 21 and the second island portion 221 of the second island lead 22. In this way, the second semiconductor element 12 can be mounted on the second island portion 221 even when the potential of the second island portion 221 is higher than the potential of the first island portion 211.

[0076] Next, we will explain the effects and benefits of semiconductor device A3.

[0077] The semiconductor device A3 comprises a first wire 41 connected to a first semiconductor element 11 and a second semiconductor element 12, and a second wire 42 connected to the first semiconductor element 11 and a first terminal lead 31. The first wire 41 contains a first metal. The second wire 42 contains a first core material portion 42A containing a second metal, and a first surface layer portion 42B containing a third metal and covering the first core material portion 42A. The atomic number of the second metal is smaller than that of the first metal. Furthermore, the bonding strength with the first terminal lead 31 is higher with the third metal than with the second metal. Therefore, the semiconductor device A3 also makes it possible to reduce the cost of the device while ensuring the required dielectric strength. Furthermore, by adopting a configuration common to the semiconductor device A1, the semiconductor device A3 achieves the same effects as the semiconductor device A1.

[0078] This disclosure is not limited to the embodiments described above. The specific configuration of each part of this disclosure can be modified in various ways.

[0079] This disclosure includes embodiments described in the following appendix. Note 1. First semiconductor device, The first and second circuits have different potentials from each other, A second semiconductor element that conducts to the first semiconductor element, relays mutual signals between the first circuit and the second circuit, and insulates the first circuit and the second circuit from each other, A first terminal lead that conducts to the first semiconductor element, A first wire connected to the first semiconductor element and the second semiconductor element, The device comprises a first semiconductor element and a second wire connected to the first terminal lead, The first wire includes a first metal, The second wire includes a first core material portion containing a second metal, and a first surface layer portion containing a third metal and covering the first core material portion. The atomic number of the second metal is smaller than the atomic number of the first metal. A semiconductor device wherein the bonding strength with the first terminal lead is higher for the third metal than for the second metal. Note 2. A third semiconductor element that conducts to the second semiconductor element, A second terminal lead that conducts to the third semiconductor element, A third wire connected to the second semiconductor element and the third semiconductor element, The third semiconductor element and the second terminal lead are further connected by a fourth wire, The third wire includes a fourth metal, The fourth wire includes a second core material portion containing a fifth metal, and a second surface layer portion containing a sixth metal and covering the second core material portion. The atomic number of the fifth metal is smaller than the atomic number of the fourth metal. The semiconductor device described in Appendix 1, wherein the bonding strength with the second terminal lead is higher for the sixth metal than for the fifth metal. Note 3. Furthermore, equipped with the first island lead, The first circuit includes the first semiconductor element, and the second circuit includes the third semiconductor element. The first island lead is included in the first circuit, The first semiconductor element is the semiconductor device described in Appendix 2, mounted on the first island lead. Note 4. Further comprising a second island lead located away from the first island lead and included in the second circuit, The third semiconductor element is the semiconductor device described in Appendix 3, mounted on the second island lead. Note 5. The second semiconductor element is the semiconductor device described in Appendix 4, mounted on the first island lead. Note 6. The second semiconductor element is the semiconductor device described in Appendix 4, mounted on the second island lead. Note 7. In the first direction, the third semiconductor element is located on the opposite side from the first semiconductor element to the second semiconductor element, as described in any of appendices 3 to 6. Note 8. The semiconductor device according to any one of appendices 3 to 7, wherein the potential of the second circuit is higher than the potential of the first circuit. Note 9. Further comprising a fifth wire and a metal block, The first island lead has a first island portion on which the first semiconductor element is mounted, and a first terminal portion extending from the first island portion. The fifth wire is connected to the first semiconductor element and the first terminal portion. The semiconductor device according to any one of appendices 3 to 8, wherein the metal block is bonded to the connection portion of the fifth wire to the first terminal portion. Note 10. The semiconductor device according to any one of the appendices 2 to 9, wherein the first metal and the fourth metal are gold. Note 11. The semiconductor device according to any one of appendices 2 to 10, wherein the second metal and the fifth metal are copper. Note 12. The semiconductor device according to any one of appendices 2 to 11, wherein the third metal and the sixth metal are palladium. Note 13. The second wire has a first main portion and a first end portion interposed between the first main portion and the first terminal lead. The first end includes a first tapered portion adjacent to the first main portion, wherein the dimension in the thickness direction of the first terminal lead decreases as it moves away from the first main portion. The semiconductor device according to any one of appendices 2 to 12, wherein the bonding interface between the first terminal lead and the second wire is provided spanning the first main portion and the first end portion when viewed in the thickness direction of the first terminal lead. Note 14. The fourth wire has a second main portion and a second end portion interposed between the second main portion and the second terminal lead, The second end includes a second tapered portion adjacent to the second main portion, the dimension in the thickness direction of the second terminal lead decreasing as it moves away from the second main portion. The semiconductor device according to any one of appendices 2 to 13, wherein the bonding interface between the second terminal lead and the fourth wire is provided spanning the second main portion and the second end portion when viewed in the thickness direction of the second terminal lead. Note 15. The first semiconductor element includes a first metal layer to which the second wire is connected, and a second metal layer that overlaps the first metal layer when viewed in the thickness direction of the first semiconductor element and is located inward in the thickness direction of the first semiconductor element. The semiconductor device according to any one of the appendices 1 to 14, wherein the bending rigidity of the first metal layer is higher than that of the second metal layer. Note 16. The first semiconductor element, the second semiconductor element, the first wire, and the second wire are further covered by a sealing resin, A semiconductor device according to any one of the appendices 1 to 15, wherein the sulfur content per unit mass of the sealing resin is 300 μg / g or less. Note 17. The second semiconductor element is an inductive type semiconductor device as described in any of appendices 1 to 16. [Explanation of Symbols]

[0080] A1, A2, A3: Semiconductor equipment 11: First semiconductor element (controller) 11A: Element body 111: First metal layer 112: Second metal layer 113: Via 114: Interlayer insulating film 115: Passivation film 116: Surface protective film 12: Second semiconductor device 121: 1st electrode 122: 2nd electrode 13: Second semiconductor element (gate driver) 131: Third metal layer 132: Fourth metallic layer 133: Via 134: Interlayer insulating film 135: Passivation film 136: Surface protective film 21: First island lead 211: First island section 211A: First mounting surface 212: First terminal section 212A: Covering section 212B:Exposed part 213:Through hole 22: Second Island Lead 221: Second Island Section 221A: Second mounting surface 222: Second terminal section 222A: Covered portion 222B: Exposed portion 23: Metal layer 31: First terminal lead 31A: First intermediate lead 31B: First side lead 311: Covering portion 311A: Joint interface 312: Exposed part 32: Second terminal lead 32A: Second intermediate lead 32B: Second side lead 321: Covering portion 321A: Bonding interface 322:Exposed part 33:Metal layer 41: First wire 42: Second wire 42A: First core material section 42B: First surface layer section 421: First main section 422: First end section 422A: First tapered section 422B: First tip section 43: Third wire 44: Fourth wire 44A: Second core material section 44B: Second surface layer section 441: Second main section 442: Second end section 442A: Second tapered section 442B: Second tip section 45: Fifth wire 45A: Third core material 45B: Third surface layer 451: Connection part 46: 6th wire 46A: 4th core material section 46B: Fourth surface layer 461: Connection part 47: Metal block 47A: Core material 47B: Surface layer part 50: Sealing resin 51:Top 52:Bottom 53: 1st side 531: 1st top 532: First lower section 533: First middle section 54:Second side 541:Second top 542: Second lower section 543: Second middle section d: Dimension (thickness direction) t1, t2, t3, t4: Thickness z: thickness direction x: first direction y: Second direction

Claims

1. A first semiconductor element constituting the first circuit, The third semiconductor element constituting the second circuit, A second semiconductor element that conducts to each of the first and third semiconductor elements and relays mutual signals between the first and second circuits, A first terminal lead that is conductive to the first semiconductor element and constitutes the first circuit, The second terminal lead, which is electrically connected to the third semiconductor element and constitutes the second circuit, A first wire connected to the first semiconductor element and the second semiconductor element, and constituting the first circuit, A second wire connected to the first semiconductor element and the first terminal lead, and constituting the first circuit, A third wire connected to the second semiconductor element and the third semiconductor element, and constituting the second circuit, The third semiconductor element and the second terminal lead are connected, and the fourth wire constitutes the second circuit, The device comprises a first semiconductor element, a second semiconductor element, a third semiconductor element, a first wire, a second wire, a third wire, and a sealing resin covering the fourth wire, The potential of the second circuit is higher than the potential of the first circuit. The second semiconductor element insulates the first circuit and the second circuit from each other. Each of the first wire and the third wire contains a first metal which is gold. The second wire includes a first core material portion containing a second metal which is copper, and a first surface layer portion containing a third metal which is palladium and covering the first core material portion. The fourth wire includes a second core material portion containing the second metal, and a second surface layer portion containing the third metal and covering the second core material portion. The atomic number of the second metal is less than the atomic number of the first metal. The bonding strength between the first terminal lead and the second terminal lead is higher with the third metal than with the second metal. Each of the first wire and the third wire does not include the second metal and the third metal, A semiconductor device wherein each of the first core material portion, the second core material portion, the first surface layer portion, and the second surface layer portion does not contain the first metal.

2. The first circuit further comprises a first island lead, The semiconductor device according to claim 1, wherein the first semiconductor element is mounted on the first island lead.

3. It further comprises a second island lead that is separated from the first island lead and constitutes the second circuit, The semiconductor device according to claim 2, wherein the third semiconductor element is mounted on the second island lead.

4. The semiconductor device according to claim 3, wherein the second semiconductor element is mounted on the first island lead.

5. The semiconductor device according to claim 3, wherein the second semiconductor element is mounted on the second island lead.

6. The semiconductor device according to any one of claims 2 to 5, wherein the third semiconductor element is located on the opposite side from the first semiconductor element with respect to the second semiconductor element in a first direction.

7. Further comprising a fifth wire and a metal block, The first island lead has a first island portion on which the first semiconductor element is mounted, and a first terminal portion extending from the first island portion. The fifth wire is connected to the first semiconductor element and the first terminal portion. The semiconductor device according to any one of claims 2 to 6, wherein the metal block is bonded to the connection portion of the fifth wire to the first terminal portion.

8. The second wire has a first main portion and a first end portion interposed between the first main portion and the first terminal lead, The first end portion is adjacent to the first main portion and includes a first tapered portion, the dimension of the first terminal lead in the thickness direction decreasing as it moves away from the first main portion. The semiconductor device according to any one of claims 1 to 7, wherein, viewed in the thickness direction of the first terminal lead, the bonding interface between the first terminal lead and the second wire spans the first main portion and the first end portion.

9. The fourth wire has a second main portion and a second end portion interposed between the second main portion and the second terminal lead, The second end portion is adjacent to the second main portion and includes a second tapered portion, the dimension of the second terminal lead in the thickness direction decreasing as it moves away from the second main portion. The semiconductor device according to any one of claims 1 to 8, wherein, viewed in the thickness direction of the second terminal lead, the bonding interface between the second terminal lead and the fourth wire spans the second main portion and the second end portion.

10. The first semiconductor element comprises a first metal layer to which the second wire is connected, and a second metal layer that overlaps the first metal layer when viewed in the thickness direction of the first semiconductor element and is located inward in the thickness direction of the first semiconductor element. The semiconductor device according to any one of claims 1 to 9, wherein the bending rigidity of the first metal layer is higher than that of the second metal layer.

11. The semiconductor device according to any one of claims 1 to 10, wherein the sulfur content per unit mass of the sealing resin is 300 μg / g or less.

12. The semiconductor device according to any one of claims 1 to 11, wherein the second semiconductor element is of the inductive type.

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