Semiconductor device

Abstract

To provide a semiconductor device capable of suppressing deterioration in characteristics of a plurality of semiconductor elements by suppressing excessive energization to a built-in diode of each semiconductor element.SOLUTION: The semiconductor device includes a plurality of first semiconductor elements, one or more first rectifying elements, a first power terminal, and a first conductor. The first semiconductor elements include a first element and a second element. A length of the shortest conduction path of the first element is shorter than a length of the shortest conduction path of the second element. The first pad portion includes a first portion and a second portion. One of the one or more first rectifying elements is disposed in the first portion. The first conductor further includes a first bonding portion. The first pad part has a first bonding surface. The first element is closest to the first bond portion among the plurality of first semiconductor elements and has a shortest conduction path to the first power terminal among the plurality of first semiconductor elements.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to semiconductor devices. [Background technology]

[0002] Recently, semiconductor devices including semiconductor elements such as MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) and IGBTs (Insulated Gate Bipolar Transistors) have become known. For example, a known configuration is one in which two semiconductor elements (a first semiconductor element and a second semiconductor element) are connected in series and a DC voltage is converted into an AC voltage by the switching operation of each semiconductor element. Furthermore, in such semiconductor devices, a configuration is known in which multiple first semiconductor elements are connected in parallel and multiple second semiconductor elements are connected in parallel to ensure a large allowable current (see, for example, Patent Document 1). The configuration described in Patent Document 1 includes multiple first semiconductor elements connected in parallel and multiple second semiconductor elements connected in parallel, with each of the multiple first semiconductor elements and each of the multiple second semiconductor elements connected in series. Each of the first and second semiconductor elements is a MOSFET and has a built-in diode. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-225493 Summary of the Invention [Problem to be solved by the invention]

[0004] In the semiconductor device described in Patent Document 1, a surge current may flow through each of the first and second semiconductor elements due to switching operations of the first and second semiconductor elements. This surge current flows through the built-in diode of each semiconductor element, and flows in the reverse direction of each semiconductor element (the forward direction of the built-in diode). Excessive current flowing through the built-in diode due to this surge current leads to deterioration of the characteristics of each semiconductor element (for example, an increase in on-resistance).

[0005] In view of the above circumstances, an object of the present disclosure is to provide a semiconductor device that can suppress excessive current flow to the built-in diode of each semiconductor element and suppress deterioration of the characteristics of a plurality of semiconductor elements. [Means for solving the problem]

[0006] The semiconductor device disclosed herein includes a plurality of first semiconductor elements each performing a switching operation and electrically connected in parallel to one another; one or more first rectifying elements electrically connected in anti-parallel to the plurality of first semiconductor elements; a first power terminal electrically connected to each of the plurality of first semiconductor elements; and a first conductor including a first pad portion to which the plurality of first semiconductor elements are bonded and electrically connected to the first power terminal and the plurality of first semiconductor elements. The plurality of first semiconductor elements include a first element and a second element having mutually different lengths of shortest conduction paths to the first power terminal. The length of the shortest conduction path of the first element is shorter than the length of the shortest conduction path of the second element. The first pad portion includes a first portion to which at least the first element of the plurality of first semiconductor elements is bonded and a second portion to which at least the second element of the plurality of first semiconductor elements is bonded. The number of first rectifying elements is less than the number of the first semiconductor elements, and one of the one or more first rectifying elements is disposed in the first portion. [Effects of the Invention]

[0007] According to the configuration based on the present disclosure, excessive current flow to the built-in diode of the semiconductor element can be suppressed, and deterioration of the characteristics of the semiconductor element can be suppressed. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view showing a semiconductor device according to a first embodiment. [Figure 2] 2 is a perspective view of FIG. 1 in which the heat sink and the case are omitted. [Figure 3] FIG. 1 is a plan view showing a semiconductor device according to a first embodiment. [Figure 4] 4 is a plan view of FIG. 3 in which the heat sink and the case are shown by imaginary lines. [Figure 5] FIG. 5 is a partially enlarged view of a part of FIG. 4. [Figure 6] FIG. 6 is a partially enlarged view of a part of FIG. 5. [Figure 7] FIG. 5 is a partially enlarged view of a part of FIG. 4. [Figure 8] FIG. 1 is a front view showing a semiconductor device according to a first embodiment. [Figure 9] 1 is a side view (left side view) showing a semiconductor device according to a first embodiment. [Figure 10] 1 is a side view (right side view) showing a semiconductor device according to a first embodiment. [Figure 11] FIG. 2 is a bottom view showing the semiconductor device according to the first embodiment. [Figure 12] FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. [Figure 13] FIG. 7 is a cross-sectional end view taken along line XIII-XIII in FIG. 6. [Figure 14] FIG. 7 is a cross-sectional end view taken along line XIV-XIV in FIG. 6. [Figure 15] 1 is a circuit diagram showing an example of a circuit configuration of a semiconductor device according to a first embodiment. [Figure 16] FIG. 10 is a plan view showing a semiconductor device according to a second embodiment. [Figure 17] FIG. 10 is a plan view showing a semiconductor device according to a third embodiment. [Figure 18] FIG. 10 is a plan view showing a semiconductor device according to a fourth embodiment. [Figure 19]FIG. 10 is a plan view showing a semiconductor device according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the semiconductor device of the present disclosure will be described below with reference to the accompanying drawings. In the following description, identical or similar components are designated by the same reference numerals, and redundant description will be omitted.

[0010] 1 to 15 show a semiconductor device A1 according to a first embodiment. The semiconductor device A1 includes a plurality of semiconductor elements 10A, 10B, a plurality of rectifying elements 20A, 20B, a support member 3, a plurality of power terminals 41, 42, 43A, 43B, a pair of signal terminals 44A, 44B, a plurality of detection terminals 45A, 45B, 46, 47, a plurality of connecting members 51, 52, 53A, 53B, 54A, 54B, 55A, 55B, 56A, 56A, 57A, 57B, 58, a heat sink 70, and a case 71.

[0011] FIG. 1 is a perspective view showing the semiconductor device A1. FIG. 2 is a perspective view of FIG. 1 with the heat sink 70 and the case 71 omitted. FIG. 3 is a plan view showing the semiconductor device A1. FIG. 4 is a view of the plan view of FIG. 3 with the heat sink 70 and the case 71 respectively indicated by imaginary lines (two-dot chain lines). FIG. 5 is a partial enlarged view of a part of FIG. 4. FIG. 6 is a partial enlarged view of a part of FIG. 5. FIG. 7 is a partial enlarged view of a part of FIG. 4. FIG. 8 is a front view showing the semiconductor device A1. FIG. 9 is a side view (left side view) showing the semiconductor device A1. FIG. 10 is a side view (right side view) showing the semiconductor device A1. FIG. 11 is a bottom view showing the semiconductor device A1. FIG. 12 is a cross-sectional view taken along line XII-XII in FIG. 4. FIG. 13 is a cross-sectional end view taken along line XIII-XIII in FIG. 6. FIG. 14 is a cross-sectional end view taken along line XIV-XIV in FIG. 6. FIG. 15 is a circuit diagram showing an example of the circuit configuration of the semiconductor device A1.

[0012] For ease of explanation, three mutually orthogonal directions are referred to as the x-direction, y-direction, and z-direction. The z-direction is the thickness direction of the semiconductor device A1. The x-direction is the left-right direction in the plan view of the semiconductor device A1 (see FIGS. 3 and 4). The y-direction is the up-down direction in the plan view of the semiconductor device A1 (see FIGS. 3 and 4). One of the x-directions is referred to as the x1-direction, and the other of the x-directions is referred to as the x2-direction. Similarly, one of the y-directions is referred to as the y1-direction, the other of the y-directions is referred to as the y2-direction, one of the z-directions is referred to as the z1-direction, and the other of the z-directions is referred to as the z2-direction. In the following explanation, "plan view" refers to the view from the z-direction. The z-direction is an example of a "thickness direction." Furthermore, the x-direction is an example of a "first direction," and the y-direction is an example of a "second direction," but the present disclosure is not limited thereto.

[0013] As shown in FIGS. 11 and 12, the heat sink 70 is a rectangular plate in plan view. The heat sink 70 is made of a material with high thermal conductivity, such as copper or a copper alloy. The surface of the heat sink 70 may be nickel-plated. If necessary, a cooling member (e.g., a heat sink) is attached to the surface of the heat sink 70 facing in the z1 direction. As shown in FIG. 12, the support member 3 is placed on the heat sink 70.

[0014] As can be seen from FIGS. 1 and 3 , the case 71 is approximately a rectangular parallelepiped. The case 71 is made of a synthetic resin having electrical insulation and excellent heat resistance, such as PPS (polyphenylene sulfide). The case 71 is rectangular in shape and approximately the same size as the heat sink 70 in a plan view. The case 71 includes a frame 73 fixed to the surface of the heat sink 70 on the z2 side, and a top plate 72 fixed to the frame 73. As shown in FIGS. 1 and 12 , the top plate 72 closes the opening of the frame 73 on the z2 side. As shown in FIG. 12 , the top plate 72 faces the heat sink 70, which closes the z1 side of the frame 73. The top plate 72, the heat sink 70, and the frame 73 define a circuit accommodating space (a space accommodating the semiconductor elements 10A and 10B, the rectifying elements 20A and 20B, the support member 3, etc.) within the case 71.

[0015] As shown in FIG. 3 , the frame portion 73 has a pair of side walls 731, 732 spaced apart in the x direction and a pair of side walls 733, 734 spaced apart in the y direction. The pair of side walls 731, 732 each extend in the y direction in a plan view. The side wall 732 is located further in the x2 direction than the side wall 731. The pair of side walls 733, 734 each extend in the x direction in a plan view. The side wall 734 is located further in the y2 direction than the side wall 733. The side wall 733 is connected to each edge portion of the pair of side walls 731, 732 on the y1 direction side, and the side wall 734 is connected to each edge portion of the pair of side walls 731, 732 on the y2 direction side.

[0016] As shown in FIGS. 1, 3, and 9, two terminal blocks 771, 772 are formed on the outer surface of the side wall 731. The two terminal blocks 771, 772 are arranged along the y direction. The terminal block 771 covers a portion of the power terminal 43A, and a portion of the power terminal 43A is arranged on the surface on the z2 direction side. The terminal block 772 covers a portion of the power terminal 43B, and a portion of the power terminal 43B is arranged on the surface on the z2 direction side. In a plan view, the terminal block 771 is arranged on the y2 direction side of the center of the side wall 731 in the length direction (y direction), and the terminal block 772 is arranged on the y1 direction side of the center of the side wall 731 in the length direction (y direction). These terminal blocks 771, 772 are formed integrally with the side wall 731.

[0017] As shown in FIGS. 1, 3, and 10, two terminal blocks 773, 774 are formed on the outer surface of the side wall 732. The two terminal blocks 773, 774 are arranged along the y direction. The terminal block 773 covers a portion of the power terminal 41, and a portion of the power terminal 41 is arranged on the surface on the z2 direction side. The terminal block 774 covers a portion of the power terminal 42, and a portion of the power terminal 42 is arranged on the surface on the z2 direction side. In a plan view, the terminal block 773 is arranged in the y2 direction with respect to the center of the length direction (y direction) of the side wall 732, and the terminal block 774 is arranged on the y1 direction side with respect to the center of the length direction (y direction) of the side wall 732. These terminal blocks 773, 774 are formed integrally with the side wall 732. For example, a nut (not shown) is embedded in each of the terminal blocks 771 to 774. The central axis of the screw hole of the nut coincides with the z direction.

[0018] As shown in FIGS. 1, 3, and 8 to 10, recesses 74 are formed at each of the four corners of the surface of the frame portion 73 on the z2 direction side. Mounting through-holes 75 are formed in the bottom wall of the recesses 74. A cylindrical metal member 76 is fitted into and fixed in the mounting through-holes 75. Mounting through-holes (see FIG. 11) communicating with the mounting through-holes 75 are formed in the heat sink 70. The semiconductor device A1 is fixed to a predetermined fixing position on an object to be mounted by fasteners (e.g., bolts) inserted through the mounting through-holes 75 of the case 71 and the mounting through-holes of the heat sink 70. These mounting through-holes 75 may be used to mount a cooling means such as the heat sink.

[0019] As shown in FIG. 15, each of the multiple semiconductor elements 10A, 10B is, for example, a MOSFET. Each of the semiconductor elements 10A, 10B may be a field-effect transistor including a metal-insulator-semiconductor FET (MISFET) or a bipolar transistor such as an IGBT instead of a MOSFET. Each of the semiconductor elements 10A, 10B has a built-in diode (not shown). Each of the semiconductor elements 10A, 10B is made of, for example, silicon carbide (SiC). Each of the semiconductor elements 10A, 10B may be made of silicon (Si), gallium arsenide (GaAs), gallium nitride (GaN), or the like instead of SiC. Each of the semiconductor elements 10A, 10B is, for example, rectangular in plan view.

[0020] 13 and 14, each of the semiconductor elements 10A and 10B has an element main surface 100a and an element back surface 100b. In each of the semiconductor elements 10A and 10B, the element main surface 100a and the element back surface 100b are spaced apart in the z direction, with the element main surface 100a facing the z2 direction and the element back surface 100b facing the z1 direction.

[0021] As shown in FIGS. 6, 13, and 14, each of the semiconductor elements 10A and 10B has a first electrode 11, a second electrode 12, a third electrode 13, and a fourth electrode 14. In each of the semiconductor elements 10A and 10B, the first electrode 11, the third electrode 13, and the fourth electrode 14 are formed on the element main surface 100a, and the second electrode 12 is formed on the element back surface 100b. In an example in which each of the semiconductor elements 10A and 10B is a MOSFET, the first electrode 11 is a source electrode, the second electrode 12 is a drain electrode, the third electrode 13 is a gate electrode, and the fourth electrode 14 is a source sense electrode (electrode for detecting a source current). The built-in diode in each of the semiconductor elements 10A and 10B has an anode connected to the first electrode 11 (source electrode) and a cathode connected to the second electrode 12 (drain electrode). When a drive signal (e.g., gate voltage) is input to the third electrode 13 (gate electrode), each of the semiconductor elements 10A and 10B switches between a conductive state and a cutoff state in response to the drive signal. This operation of switching between the conductive state and the cutoff state is called a switching operation. In the conductive state, a current flows from the second electrode 12 (drain electrode) to the first electrode 11 (source electrode), and in the cutoff state, this current does not flow. The semiconductor device A1 converts a DC voltage input between two power terminals 41 and 42 into, for example, an AC voltage through the switching operation of the multiple semiconductor elements 10A and 10B.

[0022] The semiconductor device A1 is configured, for example, as a half-bridge switching circuit. In this case, multiple semiconductor elements 10A configure the upper arm circuit of the semiconductor device A1, and multiple semiconductor elements 10B configure the lower arm circuit of the semiconductor device A1. Thus, each semiconductor element 10A and each semiconductor element 10B are connected in series to configure a bridge. In the example shown in FIGS. 2, 4, and 15, the semiconductor device A1 includes ten semiconductor elements 10A and ten semiconductor elements 10B. The number of semiconductor elements 10A and 10B is not limited to this configuration and can be changed as appropriate depending on the performance required of the semiconductor device A1.

[0023] As shown in FIGS. 4 to 7, 12, and 13, each of the semiconductor elements 10A is mounted on a support member 3. In the example shown in FIG. 4, the semiconductor elements 10A are arranged, for example, along the x direction and spaced apart from one another. Each semiconductor element 10A is conductively joined to the support member 3 (a conductor 31, described below) via a conductive joining material (e.g., a sintered metal such as sintered silver or sintered copper, a metal paste material such as silver or copper, or solder, not shown). When each semiconductor element 10A is joined to the conductor 31, the element back surface 100b faces the conductor 31.

[0024] As shown in FIGS. 4 to 7, the multiple semiconductor elements 10A include a first element 101A and a second element 102A. The first element 101A and the second element 102A have different lengths of shortest conduction paths to the power terminals 41. The shortest conduction path of the first element 101A is shorter than that of the second element 102A. In the semiconductor device A1, of the multiple semiconductor elements 10A, the semiconductor element 10A with the shortest shortest conduction path to the power terminals 41 is designated as the first element 101A, and the semiconductor element 10A with the longest shortest conduction path to the power terminals 41 is designated as the second element 102A. In addition, if, among two semiconductor elements 10A, the one with the shortest shortest conduction path to the power terminal 41 is designated as the first element 101A and the one with the longest shortest conduction path to the power terminal 41 is designated as the second element 102A, the first element 101A does not have to be the semiconductor element 10A with the shortest shortest conduction path to the power terminal 41, and the second element 102A does not have to be the semiconductor element 10A with the longest shortest conduction path to the power terminal 41.

[0025] As shown in FIGS. 4 to 7, 12, and 14, the plurality of semiconductor elements 10B are mounted on a support member 3. In the example shown in FIG. 4, the plurality of semiconductor elements 10B are arranged, for example, along the x direction and spaced apart from one another. Each semiconductor element 10B is conductively joined to the support member 3 (a conductor 32, described below) via a conductive bonding material (not shown) (for example, a sintered metal such as sintered silver or sintered copper, a metal paste material such as silver or copper, or solder). When each semiconductor element 10B is joined to the conductor 32, the element back surface 100b faces the conductor 32. In the examples shown in FIGS. 4 and 5, the plurality of semiconductor elements 10A and the plurality of semiconductor elements 10B overlap when viewed in the y direction, but they do not necessarily have to overlap.

[0026] As shown in FIGS. 4 to 7, the multiple semiconductor elements 10B include a third element 101B and a fourth element 102B. The third element 101B and the fourth element 102B have different lengths of shortest conduction paths to the power terminals 41. The shortest conduction path of the fourth element 102B is shorter than that of the third element 101B. In the semiconductor device A1, of the multiple semiconductor elements 10B, the semiconductor element 10B with the shortest shortest conduction path to the power terminals 41 is designated as the third element 101B, and the semiconductor element 10B with the longest shortest conduction path to the power terminals 41 is designated as the fourth element 102B. In addition, if, among two of the multiple semiconductor elements 10B, the one with the shortest shortest conduction path to the power terminal 41 is designated as the third element 101B and the one with the longest shortest conduction path to the power terminal 41 is designated as the fourth element 102B, the third element 101B does not have to be the semiconductor element 10B with the shortest shortest conduction path to the power terminal 41, and the fourth element 102B does not have to be the semiconductor element 10B with the longest shortest conduction path to the power terminal 41.

[0027] Each of the rectifying elements 20A, 20B is, for example, a diode. In an example in which the semiconductor elements 10A, 10B are configured with MOSFETs, the diodes are, for example, Schottky barrier diodes, as shown in FIG. 15 . Furthermore, in an example in which the semiconductor elements 10A, 10B are configured with IGBTs, fast recovery diodes are used. The rectifying elements 20A, 20B are not limited to diodes and may be any electronic component with a rectifying function, such as a transistor whose switching operation is synchronized with the switching operation of the semiconductor elements 10A, 10B.

[0028] 13 and 14, each of the rectifying elements 20A and 20B has a primary surface 200a and a rear surface 200b. In each of the rectifying elements 20A and 20B, the primary surface 200a and the rear surface 200b are spaced apart in the z direction, with the primary surface 200a facing the z2 direction and the rear surface 200b facing the z1 direction.

[0029] 13 and 14, each of the rectifying elements 20A and 20B has a first electrode 21 and a second electrode 22. The first electrode 21 is formed on the element main surface 200a, and the second electrode 22 is formed on the element back surface 200b. In an example in which each of the rectifying elements 20A and 20B is a diode (e.g., a Schottky barrier diode), the first electrode 21 is an anode electrode, and the second electrode 22 is a cathode electrode.

[0030] 15, the rectifier element 20A is electrically connected in anti-parallel to each semiconductor element 10A. This anti-parallel connection means that the forward current of each semiconductor element 10A and the forward current of the rectifier element 20A are connected in parallel in the opposite directions. Specifically, the first electrode 21 (anode electrode) of the rectifier element 20A is connected to the first electrode 11 (source electrode) of each semiconductor element 10A, and the second electrode 22 (cathode electrode) of the rectifier element 20A is connected to the second electrode 12 (drain electrode) of each semiconductor element 10A. As a result, the first electrode 21 (anode electrode) of the rectifier element 20A is electrically connected to the first electrode 11 (source electrode) of each semiconductor element 10A, and the second electrode 22 (cathode electrode) of the rectifier element 20A is electrically connected to the second electrode 12 (drain electrode) of each semiconductor element 10A. When a surge voltage occurs due to the switching operation of each semiconductor element 10A, a forward current (surge current) flows through the rectifying element 20A, and the surge voltage applied to each semiconductor element 10A is suppressed. In the example shown in Fig. 4, the rectifying element 20A is adjacent to the first element 101A. The semiconductor device A1 includes one rectifying element 20A, but may include one or more rectifying elements 20A as long as the number of rectifying elements 20A is less than the number of the multiple semiconductor elements 10A.

[0031] 15, the rectifying element 20B is electrically connected in anti-parallel to each semiconductor element 10B. This anti-parallel connection means that the forward current of each semiconductor element 10B and the forward current of the rectifying element 20B are connected in parallel in the opposite directions. Specifically, the first electrode 21 (anode electrode) of the rectifying element 20B is connected to the first electrode 11 (source electrode) of each semiconductor element 10B, and the second electrode 22 (cathode electrode) of the rectifying element 20B is connected to the second electrode 12 (drain electrode) of each semiconductor element 10B. As a result, the first electrode 21 (anode electrode) of the rectifying element 20B is electrically connected to the first electrode 11 (source electrode) of each semiconductor element 10B, and the second electrode 22 (cathode electrode) of the rectifying element 20B is electrically connected to the second electrode 12 (drain electrode) of each semiconductor element 10B. When a surge voltage occurs due to the switching operation of each semiconductor element 10B, a forward current (surge current) flows through the rectifying element 20B, thereby suppressing the surge voltage applied to each semiconductor element 10B. In the example shown in Fig. 4, the rectifying element 20B is adjacent to the third element 101B. The semiconductor device A1 includes one rectifying element 20B, but may include one or more rectifying elements 20B as long as the number of rectifying elements 20B is less than the number of semiconductor elements 10B.

[0032] The support member 3 supports the plurality of semiconductor elements 10A, 10B and the plurality of rectifying elements 20A, 20B. The support member 3 forms conductive paths between the plurality of semiconductor elements 10A, 10B and the plurality of rectifying elements 20A, 20B and the plurality of power terminals 41, 42, 43A, 43B, a pair of signal terminals 44A, 44B, and a plurality of detection terminals 45A, 45B, 46, 47. The support member 3 includes an insulating substrate 30, a plurality of conductors 31 to 33, a pair of conductors 34A, 34B, a pair of conductors 35A, 35B, and a pair of conductors 36.

[0033] The insulating substrate 30 has electrical insulation properties. The constituent material of the insulating substrate 30 is, for example, ceramics with excellent thermal conductivity. Examples of such ceramics include AlN (aluminum nitride), SiN (silicon nitride), and Al2O3 (aluminum oxide). The insulating substrate 30 has, for example, a flat plate shape.

[0034] 12 to 14, insulating substrate 30 has a main surface 301 and a back surface 302. Main surface 301 and back surface 302 are spaced apart in the z direction. Main surface 301 faces the z2 direction, and back surface 302 faces the z1 direction.

[0035] As shown in FIGS. 4 and 12, the plurality of conductors 31 to 33, the pair of conductors 34A and 34B, the pair of conductors 35A and 35B, and the pair of conductors 36 are arranged on the main surface 301 of the insulating substrate 30. The plurality of conductors 31 to 33, the pair of conductors 34A and 34B, the pair of conductors 35A and 35B, and the pair of conductors 36 are, for example, metal layers. The plurality of conductors 31 to 33, the pair of conductors 34A and 34B, the pair of conductors 35A and 35B, and the pair of conductors 36 are made of, for example, copper or a copper alloy. The plurality of conductors 31 to 33, the pair of conductors 34A and 34B, the pair of conductors 35A and 35B, and the pair of conductors 36 may be made of aluminum or an aluminum alloy instead of copper or a copper alloy. The plurality of conductors 31 to 33, the pair of conductors 34A and 34B, the pair of conductors 35A and 35B, and the pair of conductors 36 are spaced apart from one another.

[0036] A plurality of semiconductor elements 10A are mounted on the conductor 31. The conductor 31 is electrically connected to the power terminal 41. The conductor 31 includes a first pad portion 311, a first joint portion 312, and an extension portion 313. The first pad portion 311, the first joint portion 312, and the extension portion 313 are connected to each other and formed integrally.

[0037] The first pad portion 311 is bonded to the plurality of semiconductor elements 10A and is electrically connected to the second electrodes 12 (drain electrodes) of the plurality of semiconductor elements 10A. The first pad portion 311 extends from the first bonding portion 312 in the x direction. In the example shown in FIG. 4 and other figures, the first pad portion 311 is strip-shaped with the x direction as its longitudinal direction. The plurality of semiconductor elements 10A are arranged on the first pad portion 311 in the x direction. As shown in FIGS. 4, 12, and 13, the first pad portion 311 has a first bonding surface 311z. The first bonding surface 311z faces the z2 direction and is substantially parallel to the xy plane. The plurality of semiconductor elements 10A are bonded to the first bonding surface 311z.

[0038] The first pad portion 311 includes a first portion 311a and a second portion 311b. The first portion 311a and the second portion 311b are connected to each other. At least the first element 101A is bonded to the first portion 311a. In the example shown in FIGS. 4 to 7, five of the multiple semiconductor elements 10A (including the first element 101A) that have relatively short shortest conduction paths to the power terminal 41 are bonded to the first portion 311a. In addition, the rectifying element 20A is bonded to the first portion 311a. In particular, in the example shown in FIG. 5, the rectifying element 20A is bonded across the first portion 311a and the first bonding portion 312. At least the second element 102A is bonded to the second portion 311b. In the example shown in FIGS. 4 to 7, five of the multiple semiconductor elements 10A (including the second element 102A) that have relatively long shortest conduction paths to the power terminal 41 are bonded to the second portion 311b. No rectifying element 20A is bonded to the second portion 311b. In the example shown in FIG. 4, the first pad portion 311 is divided approximately in half in the x direction, with the side closer to the power terminal 41 being the first portion 311a and the side farther from the power terminal 41 being the second portion 311b. Note that if the number of multiple semiconductor elements 10A is odd, the semiconductor element 10A located at the center in the x direction may be bonded to either the first portion 311a or the second portion 311b. The regions of the first portion 311a and the second portion 311b in the first pad portion 311 are not limited to the example shown in FIG. 4 and may be set as follows. Of two semiconductor elements 10A with relatively different shortest conduction paths to the power terminals 41, the region to which the semiconductor element 10A with the shorter shortest conduction path is bonded may be designated as the first portion 311a, and the region to which the semiconductor element 10A with the longer shortest conduction path is bonded may be designated as the second portion 311b. Alternatively, the region to which semiconductor elements 10A that satisfy the following condition are bonded among multiple semiconductor elements 10A may be designated as the first portion 311a, and the remaining region may be designated as the second portion 311b. The condition is that the length of each shortest conduction path to the power terminals 41 is shorter than the average length of these shortest conduction paths. The first bonding surface 311z is formed by the upper surfaces (surfaces facing the z2 direction) of the first portion 311a and the second portion 311b.

[0039] As shown in FIGS. 4 to 6, the power terminal 41 is bonded to the first bonding portion 312. The first bonding portion 312 is strip-shaped with the y direction as the longitudinal direction. The first bonding portion 312 is connected to the edge of the first pad portion 311 on the x2 direction side. Therefore, the first element 101A is the semiconductor element 10A located furthest in the x2 direction among the multiple semiconductor elements 10A. On the other hand, the second element 102A is the semiconductor element 10A located furthest in the x1 direction among the multiple semiconductor elements 10A.

[0040] 7, the extension portion 313 extends in the y direction from the end portion on the x1-direction side of the first pad portion 311. In the example shown in Fig. 7, the extension portion 313 is disposed, in a plan view, sandwiched between the conductor 32 (a second bonding portion 322 described below) and the conductors 34A and 35A.

[0041] A plurality of semiconductor elements 10B are mounted on the conductor 32. The conductor 32 is electrically connected to each of the power terminals 43A and 43B. The conductor 32 includes a second pad portion 321 and a second joint portion 322. The second pad portion 321 and the second joint portion 322 are connected to each other and formed integrally.

[0042] The second pad portion 321 is bonded to a plurality of semiconductor elements 10B and is electrically connected to the second electrodes 12 (drain electrodes) of the plurality of semiconductor elements 10B. Furthermore, a plurality of connection members 51 are bonded to the second pad portion 321, and the second pad portion 321 is electrically connected to the first electrodes 11 (source electrodes) of the semiconductor elements 10A via the connection members 51. The second pad portion 321 extends from the second bonding portion 322 along the x-direction. In the example shown in FIG. 4 and other figures, the second pad portion 321 is strip-shaped with its longitudinal direction in the x-direction. The plurality of semiconductor elements 10B are arranged on the second pad portion 321 along the x-direction. As shown in FIGS. 4, 12, and 14, the second pad portion 321 has a second bonding surface 321z. The second bonding surface 321z faces the z2 direction and is substantially parallel to the xy plane. Each of the plurality of semiconductor elements 10B is bonded to the second bonding surface 321z.

[0043] The second pad portion 321 includes a third portion 321a and a fourth portion 321b. The third portion 321a and the fourth portion 321b are connected to each other. At least the third element 101B is bonded to the third portion 321a. In the example shown in FIGS. 4 to 7, five of the multiple semiconductor elements 10B (including the third element 101B) that have relatively short shortest conduction paths to the power terminal 41 are bonded to the third portion 321a. In addition, the rectifying element 20B is bonded to the third portion 321a. In particular, the rectifying element 20B is located between the edge of the third portion 321a that is closest to the power terminal 41 in the x direction and the third element 101B in a plan view. At least the fourth element 102B is bonded to the fourth portion 321b. 4 to 7, five of the multiple semiconductor elements 10B (including the fourth element 102B) having relatively long shortest conduction paths to the power terminal 41 are bonded to the fourth portion 321b. No rectifying element 20B is bonded to the fourth portion 321b. In the example shown in FIG. 4, the second pad portion 321 is divided approximately in half in the x direction, with the half closer to the power terminal 41 being the third portion 321a and the half farther from the power terminal 41 being the fourth portion 321b. Note that if the number of multiple semiconductor elements 10B is odd, the semiconductor element 10B disposed in the center in the x direction may be bonded to either the third portion 321a or the fourth portion 321b. The regions of the third portion 321a and the fourth portion 321b in the second pad portion 321 are not limited to the example shown in FIG. 4 and may be set as follows. Of two semiconductor elements 10B having relatively different shortest conduction paths to the power terminals 41, the region to which the semiconductor element 10B with the shorter shortest conduction path is bonded may be defined as the third portion 321a, and the region to which the semiconductor element 10B with the longer shortest conduction path is bonded may be defined as the fourth portion 321b. Alternatively, the region to which the semiconductor elements 10B that satisfy the following condition are bonded among the multiple semiconductor elements 10B may be defined as the third portion 321a, and the remaining region may be defined as the fourth portion 321b. The condition is that the length of each shortest conduction path to the power terminals 41 is shorter than the average length of these shortest conduction paths. The second bonding surface 321z is defined by the upper surfaces (surfaces facing the z2 direction) of the third portion 321a and the fourth portion 321b.

[0044] 4 and 7, a pair of power terminals 43A, 43B are joined to the second joint portion 322. The second joint portion 322 is strip-shaped with its longitudinal direction in the y direction. The second joint portion 322 is connected to the edge of the second pad portion 321 on the x1 direction side.

[0045] The conductor 33 is electrically connected to the power terminal 42. As shown in Fig. 4, the conductor 33 includes a third pad portion 331 and a third joint portion 332. The third pad portion 331 and the third joint portion 332 are connected to each other and formed integrally.

[0046] The third pad portion 331 has a plurality of connection members 52 bonded thereto, and is electrically connected to the first electrode 11 (source electrode) of each semiconductor element 10B via each connection member 52. The third pad portion 331 extends from the third bonding portion 332 along the x direction. In the example shown in FIG. 4, the third pad portion 331 is strip-shaped with its longitudinal direction in the x direction. As shown in FIGS. 4 and 12, the third pad portion 331 has a third bonding surface 331z. The third bonding surface 331z faces the z2 direction and is substantially parallel to the xy plane. Each of the plurality of connection members 52 is bonded to the third bonding surface 331z.

[0047] As shown in FIGS. 5 to 7, the third pad portion 331 includes a pair of separation portions 331a, a connecting portion 331b, and a slit 331c. The pair of separation portions 331a are separated in the y direction by the slit 331c. Multiple connection members 52 are joined to one of the pair of separation portions 331a, and the other of the pair of separation portions 331a is connected to the third joining portion 332. The pair of separation portions 331a overlap with the first portion 311a and the third portion 321a when viewed in the y direction. In other words, the slit 331c overlaps with the first portion 311a and the third portion 321a when viewed in the y direction. The connecting portion 331b is connected to each of the pair of separation portions 331a and connects the pair of separation portions 331a. Multiple connection members 52 are joined to the connecting portion 331b. The third bonding surface 331z is formed by the upper surfaces (surfaces facing the z2 direction) of the pair of separating portions 331a and connecting portion 331b.

[0048] 5 and 6, the power terminal 42 is joined to the third joint portion 332. The third joint portion 332 is strip-shaped with the y direction as the longitudinal direction. The third joint portion 332 is connected to the edge of the third pad portion 331 on the x2 direction side. In particular, the third joint portion 332 is connected to one of the pair of separation portions 331a of the third pad portion 331 (the separation portion 331a on the y1 direction side in the example shown in FIG. 5).

[0049] The pair of conductors 34A, 34B are each electrically connected to the third electrode 13 (gate electrode) of each semiconductor element 10A, 10B. As shown in FIGS. 5 to 7, the conductor 34A is electrically connected to the third electrode 13 (gate electrode) of each semiconductor element 10A via each connecting member 54A. As shown in FIGS. 5 to 7, the conductor 34B is electrically connected to the third electrode 13 (gate electrode) of each semiconductor element 10B via each connecting member 54B.

[0050] The pair of conductors 35A, 35B are each electrically connected to the fourth electrode 14 (source sense electrode) of each semiconductor element 10A, 10B. As shown in FIGS. 5 to 7, the conductor 35A is electrically connected to the fourth electrode 14 (source sense electrode) of each semiconductor element 10A via each connection member 55A. As shown in FIGS. 5 to 7, the conductor 35B is electrically connected to the fourth electrode 14 (source sense electrode) of each semiconductor element 10B via each connection member 55B.

[0051] 4 to 6, the pair of conductors 36 are not connected to anything, but in a configuration different from that of the semiconductor device A1, for example, a thermistor (not shown) is connected to each of the pair of conductors 36. The thermistor is disposed across the pair of conductors 36.

[0052] The plurality of power terminals 41, 42, 43A, and 43B, the pair of signal terminals 44A and 44B, and the plurality of detection terminals 45A, 45B, 46, and 47 are each partially exposed from the case 71.

[0053] The two power terminals 41, 42 are connected to a power source, and a power supply voltage (e.g., DC voltage) is applied to them. For example, the power terminal 41 is a positive electrode (P terminal), and the power terminal 42 is a negative electrode (N terminal). The two power terminals 41, 42 are spaced apart from each other and arranged along the y direction. Therefore, the plurality of semiconductor elements 10A and the plurality of semiconductor elements 10B are each arranged in a direction (x direction) perpendicular to the direction in which the power terminals 41 and 42 are arranged (y direction).

[0054] As shown in FIG. 15, the power terminal 41 is electrically connected to a plurality of semiconductor elements 10A. As shown in FIGS. 2 and 4, the power terminal 41 includes a tip portion 411, a base portion 412, and a rising portion 413. The tip portion 411 is formed along the surface of the terminal block 773 on the z2 direction side. The base portion 412 is disposed parallel to the tip portion 411 on the z1 direction side of the tip portion 411. The rising portion 413 connects the y1 direction edge of the tip portion 411 to the y1 direction edge of the base portion 412. Most of the base portion 412 and the rising portion 413 are embedded within the side wall 732 and the terminal block 773. A comb-tooth portion 414 that protrudes toward the inside of the case 71 is formed on the x2 direction edge of the base portion 412. The comb-tooth portion 414 is joined to the first joint portion 312 of the conductor 31 as shown in FIGS. 4 to 6. This bonding may be performed by any method, such as bonding using a conductive bonding material (e.g., solder or sintered metal), laser bonding, ultrasonic bonding, etc. By this bonding, power terminal 41 is electrically connected to each of the multiple semiconductor elements 10A via conductor 31.

[0055] As shown in FIG. 15, the power terminal 42 is electrically connected to a plurality of semiconductor elements 10B. As shown in FIGS. 2 and 4, the power terminal 42 includes a tip portion 421, a base portion 422, and a rising portion 423. The tip portion 421 is formed along the surface of the terminal block 774 on the z2 direction side. The base portion 422 is disposed parallel to the tip portion 421 on the z1 direction side of the tip portion 421. The rising portion 423 connects the y2 direction edge of the tip portion 411 to the y2 direction edge of the base portion 422. Most of the base portion 422 and the rising portion 423 are embedded within the side wall 732 and the terminal block 774. A comb-tooth portion 424 that protrudes toward the inside of the case 71 is formed on the x2 direction edge of the base portion 422. The comb-tooth portion 424 is joined to the third joint portion 332 of the conductor 33 as shown in FIGS. 4 to 6. This bonding may be performed by any method, such as bonding using a conductive bonding material (e.g., solder or sintered metal), laser bonding, ultrasonic bonding, etc. By this bonding, power terminal 42 is electrically connected to each of the plurality of semiconductor elements 10B via conductor 33.

[0056] As shown in FIG. 15, the pair of power terminals 43A, 43B are electrically connected to the connection points between each of the multiple semiconductor elements 10A and each of the multiple semiconductor elements 10B. The pair of power terminals 43A, 43B outputs an AC voltage converted by the multiple semiconductor elements 10A, 10B. In a configuration different from that of the semiconductor device A1, only one of the pair of power terminals 43A, 43B may be provided. In this case, one of the pair of power terminals 43A, 43B may be located in the center in the y direction.

[0057] As shown in FIGS. 2 and 4, each of the pair of power terminals 43A, 43B includes a tip portion 431, a base portion 432, and a rising portion 433. In the power terminal 43A, the tip portion 431 is formed along the surface on the z2 direction side of the terminal block 771. The base portion 432 is disposed parallel to the tip portion 431 on the z1 direction side of the tip portion 431. The rising portion 433 connects the y1 direction edge of the tip portion 431 to the y1 direction edge of the base portion 432. Most of the base portion 432 and the rising portion 433 are embedded within the side wall 731 and the terminal block 771. A comb-tooth portion 434 that protrudes toward the inside of the case 71 is formed on the x1 direction edge of the base portion 432. As shown in FIGS. 4 and 7, the comb-tooth portion 434 is joined to the second joint portion 322 of the conductor 32. This bonding may be performed by any method, such as bonding using a conductive bonding material (e.g., solder or sintered metal), laser bonding, or ultrasonic bonding. This bonding allows the power terminal 43B to be electrically connected to each of the semiconductor elements 10A and each of the semiconductor elements 10B via the conductors 32. Meanwhile, in the power terminal 43B, the tip portion 431 is formed along the surface on the z2 direction side of the terminal block 772. The base portion 432 is disposed parallel to the tip portion 431 on the z1 direction side of the tip portion 431. The raised portion 433 connects the y2 direction edge of the tip portion 431 to the y2 direction edge of the base portion 432. Most of the base portion 432 and the raised portion 433 are embedded within the side wall 731 and the terminal block 772. A comb-tooth portion 434 protruding toward the inside of the case 71 is formed on the x1 direction edge of the base portion 432. 4 and 7, comb-tooth portion 434 is joined to second joint portion 322 of conductor 32. This joining may be performed by any method, such as joining using a conductive joining material (such as solder or sintered metal), laser joining, or ultrasonic joining. This joining establishes electrical continuity between power terminal 43B and each of the plurality of semiconductor elements 10A and each of the plurality of semiconductor elements 10B via conductor 32.

[0058] 2 and 4, an insertion hole is formed in each of the plurality of power terminals 41, 42, 43A, and 43B. By inserting a bolt (not shown) into the insertion hole and fitting the bolt into the nut, each of the power terminals 41, 42, 43A, and 43B can be connected to a power supply device or a load provided on an object to which the semiconductor device A1 is to be attached.

[0059] A pair of signal terminals 44A, 44B are input with control signals that control the switching operation of each of the semiconductor elements 10A, 10B. As shown in Fig. 15, the signal terminal 44A is electrically connected to each of the third electrodes 13 (gate electrodes) of the multiple semiconductor elements 10A, and a control signal that controls the switching operation of each of the semiconductor elements 10A is input to the signal terminal 44A. As shown in Fig. 15, the signal terminal 44B is electrically connected to each of the third electrodes 13 (gate electrodes) of the multiple semiconductor elements 10B, and a control signal that controls the switching operation of each of the semiconductor elements 10B is input to the signal terminal 44B.

[0060] As shown in FIGS. 5 and 7, each of the pair of signal terminals 44A, 44B includes a pad portion 441 and a terminal portion 442. The pad portion 441 of each of the signal terminals 44A, 44B is housed in the case 71 (frame portion 73). As shown in FIG. 7, a connecting member 56A is joined to the pad portion 441 of the signal terminal 44A, and the pad portion 441 is electrically connected to the conductor 34A via the connecting member 56A. As shown in FIG. 5, a connecting member 56B is joined to the pad portion 441 of the signal terminal 44B, and the pad portion 441 is electrically connected to the conductor 34B via the connecting member 56B. The terminal portion 442 of each of the signal terminals 44A, 44B is exposed from the case 71. A portion of the signal terminal 44A that connects the pad portion 441 and the terminal portion 442 penetrates the side wall 734. With this configuration, the signal terminal 44A is supported by the case 71 (frame portion 73). The portion of the signal terminal 44B that connects the pad portion 441 and the terminal portion 442 penetrates the side wall 733. With this configuration, the signal terminal 44B is supported by the case 71 (frame portion 73).

[0061] The pair of detection terminals 45A, 45B outputs detection signals (source signals) indicating the operating states of the semiconductor elements 10A, 10B. As can be seen from Fig. 15, the detection terminal 45A is electrically connected to each of the fourth electrodes 14 (source sense electrodes) of the multiple semiconductor elements 10A, and outputs a voltage (voltage corresponding to the source current) applied to the fourth electrode 14 of each semiconductor element 10A. As can be seen from Fig. 15, the detection terminal 45B is electrically connected to each of the fourth electrodes 14 (source sense current) of the multiple semiconductor elements 10B, and outputs a voltage (voltage corresponding to the source current) applied to the fourth electrode 14 of each semiconductor element 10B.

[0062] As shown in FIGS. 5 and 7, each of the pair of detection terminals 45A, 45B includes a pad portion 451 and a terminal portion 452. The pad portion 451 of each of the detection terminals 45A, 45B is housed in the case 71 (frame portion 73). As shown in FIG. 7, a connecting member 57A is joined to the pad portion 451 of the detection terminal 45A, and the pad portion 451 is electrically connected to the conductor 35A via the connecting member 57A. As shown in FIG. 5, the pad portion 451 of the detection terminal 45B is electrically connected to the conductor 35B via the connecting member 57A. The terminal portion 452 of each of the detection terminals 45A, 45B is exposed from the case 71. A portion of the detection terminal 45A that connects the pad portion 451 and the terminal portion 452 penetrates the side wall 734. With this configuration, the detection terminal 45A is supported by the case 71 (frame portion 73). The portion of detection terminal 45B that connects pad portion 451 and terminal portion 452 penetrates side wall 733. With this configuration, detection terminal 45B is supported by case 71 (frame portion 73).

[0063] When a thermistor is connected to the pair of conductors 36, the pair of detection terminals 46 become terminals for detecting the temperature inside the case 71. In the example shown in Fig. 5, since a thermistor is not connected to the pair of conductors 36, the pair of detection terminals 46 are dummy terminals.

[0064] As shown in FIG. 5 , each of the pair of detection terminals 46 includes a pad portion 461 and a terminal portion 462. The pad portion 461 of each detection terminal 46 is housed in the case 71 (frame portion 73). The terminal portion 462 of each detection terminal 46 is exposed from the case 71. A portion of each detection terminal 46 that connects the pad portion 461 and the terminal portion 462 penetrates the side wall 734. With this configuration, each detection terminal 46 is supported by the case 71 (frame portion 73). When a thermistor is connected to the pair of conductors 36, each detection terminal 46 serves as a temperature detection terminal for detecting the temperature inside the case 71 by joining a connecting member (for example, a bonding wire) to each pad portion 461 and each conductor 36.

[0065] The detection terminal 47 outputs a detection signal (power supply voltage signal) corresponding to the DC voltage applied to the second electrode 12 (drain electrode) of each semiconductor element 10A. As can be seen from Fig. 15, the detection terminal 47 is electrically connected to each second electrode 12 (drain electrode) of the multiple semiconductor elements 10A, and outputs the voltage (power supply voltage) applied to the second electrode 12 of each semiconductor element 10A.

[0066] As shown in FIG. 7, the detection terminal 47 includes a pad portion 471 and a terminal portion 472. The pad portion 471 is housed in the case 71 (frame portion 73). As shown in FIG. 7, the connecting member 58 is joined to the pad portion 471, and the pad portion 471 is electrically connected to the extension portion 313 (conductor 31) via the connecting member 58. The terminal portion 472 is exposed from the case 71. A portion of the detection terminal 47 that connects the pad portion 471 and the terminal portion 472 penetrates the side wall 734. With this configuration, the detection terminal 47 is supported by the case 71 (frame portion 73).

[0067] Each of the plurality of connection members 51, 52, 53A, 53B, 54A, 54B, 55A, 55B, 56A, 56A, 57A, 57B, and 58 electrically connects two portions spaced apart from each other.

[0068] Each of the plurality of connection members 51, 52 is a metal plate. The constituent material of each of the plurality of connection members 51, 52 is, for example, copper or a copper alloy. Each of the connection members 51, 52 may be a plate-shaped laminate material or a plate-shaped composite material instead of a metal plate.

[0069] As shown in Figures 4 to 7 and 12, each of the multiple connection members 51 is joined to the first electrode 11 (source electrode) of each semiconductor element 10A and the second pad portion 321 of the conductor 32. Each connection member 51 electrically connects the first electrode 11 of each semiconductor element 10A to the second pad portion 321. As shown in Figures 4 to 7, each connection member 51 has a strip shape extending in the y direction in plan view.

[0070] As shown in Figures 4 to 7 and 12, each of the multiple connection members 52 is joined to the first electrode 11 (source electrode) of each semiconductor element 10B and the third pad portion 331 of the conductor 33. Each connection member 52 electrically connects the first electrode 11 of each semiconductor element 10B to the third pad portion 331. As shown in Figures 4 to 7, each connection member 52 has a strip shape extending in the y direction in plan view.

[0071] The plurality of connection members 53A, 53B, 54A, 54B, 55A, 55B, 56A, 56A, 57A, 57B, and 58 are each a bonding wire. The plurality of connection members 53A, 53B, 54A, 54B, 55A, 55B, 56A, 56A, 57A, 57B, and 58 are each made of aluminum, gold, copper, or an alloy containing any of these.

[0072] As shown in FIG. 6 , the connection member 53A is joined to the first electrode 21 (anode electrode) of the rectifying element 20A and the second pad portion 321 of the conductor 32, thereby establishing electrical continuity therebetween. Therefore, the first electrode 21 (anode electrode) of the rectifying element 20A and the first electrode 11 (source electrode) of each semiconductor element 10A are established via the connection member 53A, the conductor 32, and each connection member 51. As shown in FIG. 6 , the connection member 53B is joined to the first electrode 21 (anode electrode) of the rectifying element 20B and the third pad portion 331 of the conductor 33, thereby establishing electrical continuity therebetween. Therefore, the first electrode 21 (anode electrode) of the rectifying element 20B and the first electrode 11 (source electrode) of each semiconductor element 10B are established via the connection member 53B, the conductor 33, and each connection member 52.

[0073] 5 to 7, the plurality of connecting members 54A are bonded to the third electrode 13 (gate electrode) and the conductor 34A of each semiconductor element 10A, thereby providing electrical continuity therebetween. The plurality of connecting members 54B are bonded to the third electrode 13 (gate electrode) and the conductor 34B of each semiconductor element 10B, thereby providing electrical continuity therebetween, as shown in FIGS.

[0074] 5 to 7, the plurality of connection members 55A are joined to the fourth electrodes 14 (source sense electrodes) of the semiconductor elements 10A and the conductors 35A, thereby establishing electrical continuity therebetween. The plurality of connection members 55B are joined to the fourth electrodes 14 (source sense electrodes) of the semiconductor elements 10B and the conductors 35B, respectively, thereby establishing electrical continuity therebetween, as shown in FIGS.

[0075] As shown in FIG. 7, the connection member 56A is bonded to the conductor 34A and the pad portion 441 of the signal terminal 44A, thereby establishing electrical continuity therebetween. Since the conductor 34A is electrically connected to the third electrode 13 (gate electrode) of each semiconductor element 10A via each connection member 54A, the signal terminal 44A is electrically connected to the third electrode 13 (gate electrode) of each semiconductor element 10A via the connection member 56A, the conductor 34A, and each connection member 54A. Therefore, the signal terminal 44A serves as an input terminal for a control signal input to the third electrode 13 (gate electrode) of each semiconductor element 10A. As shown in FIG. 5, the connection member 56B is bonded to the conductor 34B and the pad portion 441 of the signal terminal 44B, thereby establishing electrical continuity therebetween. Since the conductor 34B is electrically connected to the third electrode 13 (gate electrode) of each semiconductor element 10B via each connection member 54B, the signal terminal 44B is electrically connected to the third electrode 13 (gate electrode) of each semiconductor element 10B via the connection member 56B, the conductor 34B, and each connection member 54B. Therefore, the signal terminal 44B serves as an input terminal for a control signal input to the third electrode 13 (gate electrode) of each semiconductor element 10B.

[0076] As shown in FIG. 7, the connection member 57A is joined to the conductor 35A and the pad portion 451 of the detection terminal 45A, thereby establishing electrical continuity between them. The conductor 35A is electrically connected to the fourth electrode 14 (source sense electrode) of each semiconductor element 10A via each connection member 55A, and therefore the detection terminal 45A is electrically connected to the fourth electrode 14 (source sense electrode) of each semiconductor element 10A via the connection member 57A, the conductor 35A, and each connection member 55A. Thus, the source current output from the fourth electrode 14 (source sense electrode) of each semiconductor element 10A is detected from the detection terminal 45A. As shown in FIG. 5, the connection member 57B is joined to the conductor 35B and the pad portion 451 of the detection terminal 45B, thereby establishing electrical continuity between them. Since the conductor 35B is electrically connected to the fourth electrode 14 (source sense electrode) of each semiconductor element 10B via each connection member 55B, the detection terminal 45B is electrically connected to the fourth electrode 14 (source sense electrode) of each semiconductor element 10B via the connection member 57B, the conductor 35B, and each connection member 55B. Therefore, the source current output from the fourth electrode 14 (source sense electrode) of each semiconductor element 10B is detected from the detection terminal 45B.

[0077] 7, the connection member 58 is joined to the extension portion 313 of the conductor 31 and the pad portion 471 of the detection terminal 47, thereby establishing electrical continuity between them. Since the conductor 31 is electrically connected to the second electrode 12 (drain electrode) of each semiconductor element 10A, the detection terminal 47 is electrically connected to the second electrode 12 (drain electrode) of each semiconductor element 10A via the connection member 58 and the conductor 31.

[0078] In a configuration different from that of the semiconductor device A1, if a thermistor is connected to a pair of conductors 36, the semiconductor device may further include connecting members that connect each conductor 36 to each detection terminal 46 (pad portion 461).

[0079] The functions and effects of the semiconductor device A1 are as follows.

[0080] The semiconductor device A1 includes a plurality of first semiconductor elements (semiconductor element 10A or semiconductor element 10B) and one or more first rectifier elements (rectifier element 20A or rectifier element 20B). The first rectifier elements are electrically connected in anti-parallel to the plurality of first semiconductor elements. With this configuration, even if a surge current occurs due to the switching operations of the plurality of first semiconductor elements, the first rectifier elements are energized, thereby reducing the current flowing through the built-in diodes of the plurality of first semiconductor elements. In other words, the semiconductor device A1 can suppress the energization of the built-in diodes of each first semiconductor element and suppress deterioration of the characteristics of each first semiconductor element.

[0081] In the semiconductor device A1, the multiple semiconductor elements 10A include a first element 101A and a second element 102A, each having a different length of shortest conduction path to the power terminal 41. The length of the shortest conduction path of the first element 101A is shorter than the length of the shortest conduction path of the second element 102A. The rectifying element 20A is disposed in a first portion 311a to which at least the first element 101A is joined. Research by the inventors has revealed that in a semiconductor device that does not include the rectifying element 20A, when a surge current is generated by the switching operations of the multiple semiconductor elements 10A, the semiconductor element 10A with the shortest shortest conduction path to the power terminal 41 has a larger current flowing through its built-in diode. That is, the semiconductor element 10A (first element 101A) with a shortest shortest conduction path to the power terminal 41 has a higher possibility of causing excessive current flow through its built-in diode than the semiconductor element 10A (second element 102A) with a long shortest conduction path to the power terminal 41. Therefore, in the semiconductor device A1, the rectifying element 20A is disposed in the first portion 311a of the first pad portion 311, thereby reducing the current flowing through the built-in diode of the semiconductor element 10A (first element 101A), which is likely to cause excessive current flow. That is, the semiconductor device A1 can suppress excessive current flow through the built-in diode of the first element 101A and suppress deterioration of the characteristics of the first element 101A. In particular, in the semiconductor device A1, the number of rectifying elements 20A is smaller than the number of semiconductor elements 10A, and deterioration of the characteristics of the multiple semiconductor elements 10A can be suppressed without providing the same number of rectifying elements 20A as the multiple semiconductor elements 10A.

[0082] In the semiconductor device A1, the multiple semiconductor elements 10B include a third element 101B and a fourth element 102B, each having a different length of shortest conduction path to the power terminal 41. The length of the shortest conduction path of the third element 101B is shorter than the length of the shortest conduction path of the fourth element 102B. The rectifying element 20B is disposed in a third portion 321a to which at least the third element 101B is joined. Research by the inventors has revealed that, similar to the multiple semiconductor elements 10A, the semiconductor element 10B with the shortest shortest conduction path to the power terminal 41 has a larger current flowing through its built-in diode. In other words, the semiconductor element 10B (third element 101B) with the shortest shortest conduction path to the power terminal 41 has a larger current flowing through its built-in diode than the semiconductor element 10B (fourth element 102B) with the longest shortest conduction path to the power terminal 41, which increases the likelihood of excessive current flow. Therefore, in the semiconductor device A1, the rectifying element 20B is disposed in the third portion 321a of the second pad portion 321, thereby reducing the current flowing through the built-in diode of the semiconductor element 10B (third element 101B), which is likely to be subject to excessive current flow. In other words, the semiconductor device A1 can suppress excessive current flow through the built-in diode of the third element 101B, thereby suppressing deterioration in the characteristics of the third element 101B. In particular, in the semiconductor device A1, the number of rectifying elements 20B is smaller than the number of semiconductor elements 10B, and deterioration in the characteristics of the plurality of semiconductor elements 10B can be suppressed without having to provide the same number of rectifying elements 20B as the plurality of semiconductor elements 10B.

[0083] In the semiconductor device A1, the first element 101A is the semiconductor element 10A with the shortest conduction path to the power terminal 41 among the multiple semiconductor elements 10A. The rectifying element 20A is adjacent to the first element 101A. This configuration further reduces excessive current flow to the built-in diode of the first element 101A by using the rectifying element 20A. In particular, in the semiconductor device A1, the rectifying element 20A is disposed between the first element 101A and an edge of the first portion 311a that connects to the first joint 312 to which the power terminal 41 is joined. Research by the inventors has shown that disposing the rectifying element 20A in this position is the most effective in reducing the current flowing through the built-in diode of the first element 101A. Because the first element 101A has the shortest conduction path to the power terminal 41 among the multiple semiconductor elements 10A, excessive current flow to the built-in diode is highly likely to occur. Therefore, in the semiconductor device A1, excessive current flow to the built-in diode in the first element 101A, which is likely to be excessively current-carrying, can be suppressed, and such an arrangement of the rectifier element 20A is preferable in terms of suppressing deterioration of the characteristics of the multiple semiconductor elements 10A.

[0084] In the semiconductor device A1, the third element 101B is the semiconductor element 10B with the shortest conduction path to the power terminal 41 among the multiple semiconductor elements 10B. Furthermore, the rectifying element 20B is adjacent to the third element 101B. With this configuration, the rectifying element 20B can further suppress excessive current flow to the built-in diode of the third element 101B. Therefore, in the semiconductor device A1, the third element 101B, which is likely to experience excessive current flow, can suppress excessive current flow to the built-in diode. Therefore, such an arrangement of the rectifying element 20B is preferable for suppressing deterioration of the characteristics of the multiple semiconductor elements 10B.

[0085] In the semiconductor device A1, the multiple semiconductor elements 10A are arranged along a direction (x direction) perpendicular to the direction (y direction) in which the power terminals 41 and 42 are aligned. In this configuration, there is a large difference in distance between the shortest conduction paths from the power terminal 41 to the multiple semiconductor elements 10A. This causes a large difference in the distance between the shortest conduction paths from the power terminal 41 to the multiple semiconductor elements 10A. This increases the current flow to the built-in diode of the first element 101A. Therefore, in the semiconductor device A1, arranging the rectifying element 20A near the first element 101A is effective in suppressing deterioration in the characteristics of each semiconductor element 10A. Similarly, in the semiconductor device A1, the multiple semiconductor elements 10B are arranged along a direction (x direction) perpendicular to the direction (y direction) in which the power terminals 41 and 42 are aligned. Therefore, in the semiconductor device A1, arranging the rectifying element 20B near the third element 101B is effective in suppressing deterioration in the characteristics of each semiconductor element 10B.

[0086] Fig. 16 shows a semiconductor device A2 according to the second embodiment. Fig. 16 is a plan view showing the semiconductor device A2, with the heat sink 70 and the case 71 omitted. The semiconductor device A2 differs from the semiconductor device A1 in that it includes a plurality of rectifying elements 20A and a plurality of rectifying elements 20B.

[0087] 16 includes three rectifying elements 20A and three rectifying elements 20B. Each of the three rectifying elements 20A is bonded to the first portion 311a of the first pad portion 311. Therefore, in the semiconductor device A2, similar to the semiconductor device A1, none of the rectifying elements 20A is bonded to the second portion 311b.

[0088] 16, the rectifying element 20A, the semiconductor element 10A (first element 101A), the semiconductor element 10A, the rectifying element 20A, the semiconductor element 10A, the semiconductor element 10A, the rectifying element 20A, the semiconductor element 10A, the semiconductor element 10A, the rectifying element 20A, and the semiconductor element 10A are arranged in this order along the x direction from the edge of the first portion 311a on the x2 direction side (the side closer to the power terminal 41) to the edge on the x1 direction side. Note that this arrangement of the multiple rectifying elements 20A is just one example and is not limited to the example shown in FIG. 16. For example, unlike the example shown in FIG. 16, the multiple rectifying elements 20A may be arranged together around the first element 101A.

[0089] Each of the three rectifying elements 20B is bonded to the third portion 321a of the second pad portion 321. Therefore, in the semiconductor device A2, similar to the semiconductor device A1, none of the rectifying elements 20B is bonded to the fourth portion 321b.

[0090] 16, the rectifying element 20B, the semiconductor element 10B (the third element 101B), the semiconductor element 10B, the rectifying element 20B, the semiconductor element 10B, the semiconductor element 10B, the rectifying element 20B, the semiconductor element 10B, the semiconductor element 10B, the rectifying element 20B, and the semiconductor element 10B are arranged in this order along the x direction from the edge of the third portion 321a on the x2 side (the side closer to the power terminal 41) to the edge on the x1 side. Note that this arrangement of the multiple rectifying elements 20B is just one example and is not limited to the example shown in FIG. 16. For example, unlike the example shown in FIG. 16, the multiple rectifying elements 20B may be arranged together around the third element 101B.

[0091] The semiconductor device A2 can also achieve the same effects as the semiconductor device A1. In particular, in the semiconductor device A2, one of the multiple rectifying elements 20A is bonded to the same position as the rectifying element 20A of the semiconductor device A1. Therefore, in the semiconductor device A2, as in the semiconductor device A1, excessive current flow to the built-in diode of the first element 101A (semiconductor element 10A), which is likely to be subject to excessive current flow, can be suppressed. Similarly, in the semiconductor device A2, one of the multiple rectifying elements 20B is bonded to the same position as the rectifying element 20B of the semiconductor device A1. Therefore, in the semiconductor device A2, as in the semiconductor device A1, excessive current flow to the built-in diode of the third element 101B (semiconductor element 10B), which is likely to be subject to excessive current flow, can be suppressed.

[0092] In the second embodiment, the number and arrangement of the multiple rectifying elements 20A are not limited to the example shown in FIG. 16 . As long as at least one of the multiple rectifying elements 20A is bonded to the first portion 311a, the other rectifying elements 20A may be bonded to either the first portion 311a or the second portion 311b. However, bonding all of the multiple rectifying elements 20A to the first portion 311a is more effective in suppressing deterioration of the characteristics of the multiple semiconductor elements 10A. Similarly, the number and arrangement of the multiple rectifying elements 20B are not limited to the example shown in FIG. 16 . As long as at least one of the multiple rectifying elements 20B is bonded to the third portion 321a, the other rectifying elements 20B may be bonded to either the third portion 321a or the fourth portion 321b. However, bonding all of the multiple rectifying elements 20B to the third portion 321a is more effective in suppressing deterioration of the characteristics of the multiple semiconductor elements 10B.

[0093] Fig. 17 shows a semiconductor device A3 according to the third embodiment. Fig. 17 is a plan view showing the semiconductor device A3, omitting the heat sink 70 and the case 71. The semiconductor device A3 differs from the semiconductor device A1 in the arrangement and connection method of the rectifying elements 20A and 20B.

[0094] 17, the connecting member 51 joined to the first element 101A partially overlaps the rectifying element 20A in a plan view, and the overlapping portion is joined to the first electrode 21 (anode electrode) of the rectifying element 20A. This establishes electrical continuity between the first electrode 21 (anode electrode) of the rectifying element 20A and the first electrode 11 (source electrode) of the first element 101A via the connecting member 51.

[0095] 17, the connecting member 52 joined to the third element 101B partially overlaps the rectifying element 20B in a plan view, and the overlapping portion is joined to the first electrode 21 (anode electrode) of the rectifying element 20B. This establishes electrical continuity between the first electrode 21 (anode electrode) of the rectifying element 20B and the first electrode 11 (source electrode) of the third element 101B via the connecting member 52.

[0096] The semiconductor device A3 can also achieve the same effects as the semiconductor device A1.

[0097] In the third embodiment, an example has been shown in which the rectifying element 20A is disposed further in the y2 direction than the first element 101A, but the rectifying element 20A may be disposed further in the y1 direction than the first element 101A. Similarly, in the third embodiment, an example has been shown in which the rectifying element 20B is disposed further in the y2 direction than the third element 101B, but the rectifying element 20B may be disposed further in the y1 direction than the third element 101B.

[0098] In the third embodiment, an example was shown in which the semiconductor device A3 includes one rectifying element 20A and one rectifying element 20B, but similar to the semiconductor device A2, the semiconductor device A3 may include a plurality of rectifying elements 20A and a plurality of rectifying elements 20B. However, the number of rectifying elements 20A is less than the number of semiconductor elements 10A, and the number of rectifying elements 20B is less than the number of semiconductor elements 10B.

[0099] Fig. 18 shows a semiconductor device A4 according to the fourth embodiment. Fig. 18 is a plan view showing the semiconductor device A4, with the heat sink 70 and case 71 indicated by imaginary lines (two-dot chain lines). The semiconductor device A4 differs from the semiconductor device A1 in that the third pad portion 331 of the conductor 33 does not have a slit 331c formed therein.

[0100] In the semiconductor device A4, the third pad portion 331 is formed in a strip shape extending in the x-direction from the third bonding portion 332. The third pad portion 331 does not have a slit 331c formed therein, and therefore is not separated into a pair of separation portions 331a.

[0101] The semiconductor device A4 can also achieve the same effects as the semiconductor device A1.

[0102] In the first to fourth embodiments, each of the semiconductor devices A1 to A4 includes one or more rectifying elements 20A and one or more rectifying elements 20B. Semiconductor devices different from these examples may not include either the rectifying element 20A or the rectifying element 20B. For example, the arrangement and shape of the power terminals 41, 42, 43A, and 43B, the arrangement and shape of the conductors 31, 32, and 33, and the arrangement of the semiconductor elements 10A and 10B may reduce the difference in distance between the shortest conduction paths from the power terminal 41 to each semiconductor element 10A. Such semiconductor devices may not require the rectifying element 20A because excessive current may not be applied to the built-in diodes of the semiconductor elements 10A. Similarly, the difference in distance between the shortest conduction paths from the power terminal 41 to each semiconductor element 10B may reduce the difference in distance. Such semiconductor devices may not require the rectifying element 20B because excessive current may not be applied to the built-in diodes of the semiconductor elements 10B.

[0103] Fig. 19 shows a semiconductor device A5 according to the fifth embodiment. Fig. 19 is a plan view showing the semiconductor device A5, in which a heat sink 70 and a case 71 are indicated by imaginary lines (two-dot chain lines). The semiconductor device A5 differs from the semiconductor device A1 in that it does not include the rectifying element 20A and the rectifying element 20B.

[0104] In the semiconductor device A5, as in the semiconductor device A1, a slit 331c is formed in the third pad portion 331 (conductor 33). With this configuration, it is possible to reduce the difference between the shortest conductive paths from the multiple semiconductor elements 10B to the power terminals 42. As a result, the semiconductor device A5 can reduce the internal inductance compared to a case in which the slit 331c is not formed in the third pad portion 331. This also applies to the semiconductor devices A1 to A3 in which the slit 331c is formed in the third pad portion 331.

[0105] In the first to fifth embodiments, examples have been shown in which multiple semiconductor elements 10A, 10B and support member 3 are housed in heat sink 70 and case 71, but this is not limited to this and they may be covered with a resin package made of, for example, epoxy resin.

[0106] The semiconductor device according to the present disclosure is not limited to the above-described embodiments. The specific configuration of each part of the semiconductor device according to the present disclosure can be freely modified in various ways. For example, the semiconductor device according to the present disclosure includes the embodiments described in the following appendices. Appendix 1. a plurality of first semiconductor elements each performing a switching operation and electrically connected in parallel to one another; one or more first rectifying elements electrically connected in anti-parallel to the plurality of first semiconductor elements; a first power terminal electrically connected to each of the plurality of first semiconductor elements; a first conductor including a first pad portion to which the plurality of first semiconductor elements are bonded and electrically connected to the first power terminal and the plurality of first semiconductor elements; It is equipped with the plurality of first semiconductor elements include first elements and second elements having mutually different lengths of shortest conduction paths to the first power terminal; a length of the shortest conduction path of the first element is shorter than a length of the shortest conduction path of the second element; the first pad portion includes a first portion to which at least the first element of the plurality of first semiconductor elements is bonded, and a second portion to which at least the second element of the plurality of first semiconductor elements is bonded, the number of the first rectifying elements is less than the number of the first semiconductor elements; A semiconductor device, wherein one of the one or more first rectifying elements is disposed in the first portion. Appendix 2. 2. The semiconductor device according to claim 1, wherein the number of the first rectifying elements is one. Appendix 3. a plurality of second semiconductor elements each performing a switching operation and electrically connected in parallel to one another; a second conductor including second pad portions to which the plurality of second semiconductor elements are bonded and spaced apart from the first conductor; It also has 3. The semiconductor device according to claim 1, wherein each of the plurality of first semiconductor elements and each of the plurality of second semiconductor elements are electrically connected in series. Appendix 4. a second power terminal electrically connected to each of the plurality of second semiconductor elements; a third power terminal electrically connected to a connection point between each of the plurality of first semiconductor elements and each of the plurality of second semiconductor elements; 4. The semiconductor device according to claim 3, further comprising: Appendix 5. further comprising a third conductor spaced apart from the first conductor and the second conductor; the first power terminal is joined to the first electrical conductor; the second power terminal is joined to the third electrical conductor; 5. The semiconductor device according to claim 4, wherein the third power terminal is joined to the second conductor. Appendix 6. a plurality of first connection members each electrically connecting each of the plurality of first semiconductor elements to the second conductor; a plurality of second connection members each electrically connecting each of the plurality of second semiconductor elements to the third conductor; It also has the second pad portion is further joined to each of the plurality of first connection members, 6. The semiconductor device according to claim 5, wherein the third conductor includes a third pad portion to which each of the plurality of second connection members is joined. Appendix 7. further comprising one or more second rectifying elements electrically connected in anti-parallel to the plurality of second semiconductor elements, the plurality of second semiconductor elements include third elements and fourth elements having mutually different lengths of shortest conduction paths to the first power terminal; a length of the shortest conduction path of the third element is shorter than a length of the shortest conduction path of the fourth element; the second pad portion includes a third portion to which at least the third element of the plurality of second semiconductor elements is bonded, and a fourth portion to which at least the fourth element of the plurality of second semiconductor elements is bonded, the number of the second rectifying elements is less than the number of the second semiconductor elements; 7. The semiconductor device according to claim 6, wherein one of the one or more second rectifying elements is disposed in the third portion. Appendix 8. 8. The semiconductor device according to claim 7, wherein the number of the second rectifying elements is one. Appendix 9. the first conductor further includes a first joint portion connected to the first pad portion and to which the first power terminal is joined; The semiconductor device of either Appendix 7 or Appendix 8, wherein the first pad portion has a first bonding surface to which each of the plurality of first semiconductor elements is bonded, and when viewed in a thickness direction perpendicular to the first bonding surface, extends from the first bonding portion along a first direction perpendicular to the thickness direction. Appendix 10. the plurality of first semiconductor elements are arranged along the first direction, the first element is the closest to the first junction among the plurality of first semiconductor elements and has the shortest shortest conduction path to the first power terminal among the plurality of first semiconductor elements; 10. The semiconductor device of claim 9, wherein one of the one or more first rectifying elements is arranged, in the thickness direction, between an edge of the first portion that connects to the first junction and the first element. Appendix 11. the second conductor further includes a second joint portion connected to the second pad portion and to which the third power terminal is joined; 11. The semiconductor device according to claim 10, wherein the second pad portion extends from the second bonding portion along the first direction when viewed in the thickness direction. Appendix 12. 12. The semiconductor device according to claim 11, wherein the plurality of second semiconductor elements are arranged along the first direction. Appendix 13. the third conductor is connected to the third pad portion and further includes a third joint portion to which the second power terminal is joined; 13. The semiconductor device according to claim 12, wherein the third pad portion extends from the third bonding portion along the first direction when viewed in the thickness direction. Appendix 14. the first pad portion, the second pad portion, and the third pad portion overlap one another when viewed in the thickness direction and a second direction perpendicular to the first direction; 14. The semiconductor device according to claim 13, wherein the first pad portion and the third pad portion are located on opposite sides of the second pad portion in the second direction. Appendix 15. 15. The semiconductor device according to claim 14, wherein the first power terminal and the second power terminal are arranged along the second direction. Appendix 16. The semiconductor device described in Appendix 15, wherein the first power terminal and the second power terminal are located on opposite sides of the third power terminal in the first direction, with the first pad portion, the second pad portion, and the third pad portion sandwiched between them. Appendix 17. When viewed in the second direction, the plurality of first semiconductor elements and the plurality of second semiconductor elements overlap each other, each of the plurality of first connection members extends along the second direction when viewed in the thickness direction; 17. The semiconductor device according to claim 16, wherein each of the plurality of second connection members extends along the second direction when viewed in the thickness direction. Appendix 18. When viewed in the second direction, the first element and the third element overlap each other, the third element has the shortest shortest conduction path to the first power terminal among the plurality of second semiconductor elements; A semiconductor device as described in Appendix 17, wherein one of the one or more second rectifying elements is arranged, as viewed in the thickness direction, between an edge of the third portion that is closer to the first power terminal in the first direction and the third element. Appendix 19. the third pad portion includes a slit extending in the first direction as viewed in the thickness direction and a pair of separation portions separated in the second direction by the slit, 19. The semiconductor device of claim 18, wherein each of the pair of isolation portions overlaps with the third portion when viewed in the second direction. Appendix 20. each of the plurality of first semiconductor elements and each of the plurality of second semiconductor elements is a MOSFET; 19. The semiconductor device according to claim 7, wherein the one or more first rectifying elements and the one or more second rectifying elements are Schottky barrier diodes. [Explanation of symbols]

[0107] A1 to A5: Semiconductor device 10A, 10B: Semiconductor element 100a: element main surface 100b: element back surface 101A: First element 102A: Second element 101B: Third element 102B: Fourth element 11: 1st electrode 12: 2nd electrode 13: 3rd electrode 14: 4th electrode 20A, 20B: Rectifying element 200a: Element main surface 200b: Back surface of element 21: First electrode 22: Second electrode 3: Support member 30: Insulating substrate 301: Main surface 302: Back surface 31: Conductor 311: First pad section 311a: First section 311b: 2nd part 311z: 1st joint surface 312: First joint part 313: Extension part 32: Conductor 321: Second pad portion 321a: Part 3 321b: Part 4 321z: 2nd joint surface 322: 2nd joint part 33: Conductor 331: Third pad portion 331a: Separation part 331b: Connection part 331c: Slit 331z: Third joint surface 332: Third joint 34A, 34B: Conductor 35A, 35B: Electric conductor 36: Electric conductor 41: Power terminal 411: Tip 412: Base 413: Standing part 414: Comb teeth part 42: Power terminal 421: Tip 422: Base 423: Rising part 424: Comb part 43A, 43B: Power terminal 431: Tip 432: Base 433: Standing part 434: Comb tooth portion 44A, 44B: Signal terminals 441: Pad section 442: Terminal section 45A, 45B: Detection terminals 451: Pad section 452: Terminal section 46: Detection terminal 461: Pad section 462: Terminal section 47: Detection terminal 471: Pad section 472:Terminal section 51, 52, 53A, 53B, 54A, 54B: connecting members 55A, 55B, 56A, 56B, 57A, 57B, 58: connecting members 70: Heat sink 71: Case 72: Top plate 73: Frame 731-734: Side wall 74: Recess 75: Mounting through hole 76: Cylindrical metal member 771~774:Terminal block

Claims

1. a plurality of first semiconductor elements each performing a switching operation and electrically connected in parallel to one another; one or more first rectifying elements electrically connected in anti-parallel to the plurality of first semiconductor elements; a first power terminal electrically connected to each of the plurality of first semiconductor elements; a first conductor including a first pad portion to which the plurality of first semiconductor elements are bonded and electrically connected to the first power terminal and the plurality of first semiconductor elements; It is equipped with the plurality of first semiconductor elements include first elements and second elements having mutually different lengths of shortest conduction paths to the first power terminal; a length of the shortest conduction path of the first element is shorter than a length of the shortest conduction path of the second element; the first pad portion includes a first portion to which at least the first element of the plurality of first semiconductor elements is bonded, and a second portion to which at least the second element of the plurality of first semiconductor elements is bonded, the number of the first rectifying elements is less than the number of the first semiconductor elements; one of the one or more first rectifying elements is disposed in the first portion; the first conductor further includes a first joint portion connected to the first pad portion and to which the first power terminal is joined; the first pad portion has a first bonding surface to which each of the plurality of first semiconductor elements is bonded; The first element is the closest to the first junction among the plurality of first semiconductor elements, and has the shortest shortest conduction path to the first power terminal among the plurality of first semiconductor elements.

2. 2. The semiconductor device according to claim 1, wherein one of the one or more first rectifying elements is disposed between an edge of the first portion connected to the first junction and the first element, as viewed in a thickness direction of the first junction surface.

3. The semiconductor device according to claim 1 , wherein one of the one or more first rectifying elements is disposed between the first element and the first power terminal when viewed in a thickness direction of the first junction surface.

4. The semiconductor device according to claim 3 , wherein one of the one or more first rectifying elements is disposed across both the first portion and the first junction portion.

5. 5. The semiconductor device according to claim 1, wherein the number of said first rectifying elements is one.

6. a plurality of second semiconductor elements each performing a switching operation and electrically connected in parallel to one another; a second conductor including second pad portions to which the plurality of second semiconductor elements are bonded and spaced apart from the first conductor; It also has 6. The semiconductor device according to claim 1, wherein each of said plurality of first semiconductor elements and each of said plurality of second semiconductor elements are electrically connected in series.

7. a second power terminal electrically connected to each of the plurality of second semiconductor elements; a third power terminal electrically connected to a connection point between each of the first semiconductor elements and each of the second semiconductor elements; The semiconductor device according to claim 6 , further comprising:

8. further comprising a third conductor spaced apart from the first conductor and the second conductor; the first power terminal is joined to the first electrical conductor; the second power terminal is joined to the third conductor; The semiconductor device according to claim 7 , wherein the third power terminal is joined to the second conductor.

9. a plurality of first connection members each electrically connecting each of the plurality of first semiconductor elements to the second conductor; a plurality of second connection members each electrically connecting each of the plurality of second semiconductor elements to the third conductor; It also has the second pad portion is further joined to each of the plurality of first connection members, 9. The semiconductor device according to claim 8, wherein said third conductor includes a third pad portion to which each of said plurality of second connection members is joined.

10. further comprising one or more second rectifying elements electrically connected in anti-parallel to the plurality of second semiconductor elements, the plurality of second semiconductor elements include third elements and fourth elements having mutually different lengths of shortest conduction paths to the first power terminal; a length of the shortest conduction path of the third element is shorter than a length of the shortest conduction path of the fourth element; the second pad portion includes a third portion to which at least the third element of the plurality of second semiconductor elements is bonded, and a fourth portion to which at least the fourth element of the plurality of second semiconductor elements is bonded, the number of the second rectifying elements is less than the number of the second semiconductor elements; The semiconductor device according to claim 9 , wherein one of the one or more second rectifying elements is disposed in the third portion.

11. The semiconductor device according to claim 10 , wherein the number of said second rectifying elements is one.

12. The semiconductor device according to claim 10 , wherein one of the one or more second rectifying elements is disposed between the third element and the first power terminal as viewed in a thickness direction of the first junction surface.

13. 13. The semiconductor device of claim 12, wherein the second rectifying element arranged between the third element and the first power terminal has a length in a second direction perpendicular to the thickness direction and the first direction in which the first pad portion extends that is longer than the length in the first direction.

14. the second conductor further includes a second joint portion connected to the second pad portion and to which the third power terminal is joined; The semiconductor device according to claim 11 , wherein the second pad portion extends along a first direction that is a direction in which the first pad portion extends from the second bonding portion when viewed in a thickness direction of the first bonding surface.

15. The semiconductor device according to claim 14 , wherein the plurality of second semiconductor elements are arranged along the first direction.

16. the third conductor further includes a third joint portion connected to the third pad portion and to which the second power terminal is joined; The semiconductor device according to claim 15 , wherein the third pad portion extends from the third bonding portion along the first direction when viewed in the thickness direction.

17. The semiconductor device according to claim 16 , wherein the one second rectifying element is disposed between the third element and the third junction portion when viewed in the thickness direction of the first junction surface.

18. the first pad portion, the second pad portion, and the third pad portion overlap one another when viewed in the thickness direction and a second direction perpendicular to the first direction, 18. The semiconductor device according to claim 16, wherein the first pad portion and the third pad portion are located on opposite sides of the second pad portion in the second direction.

19. The first power terminal and the second power terminal are arranged along the second direction.

19. The semiconductor device according to claim 18.

20. 20. The semiconductor device according to claim 19, wherein the first power terminal and the second power terminal are located on opposite sides of the third power terminal in the first direction, with the first pad portion, the second pad portion, and the third pad portion sandwiched therebetween.

21. When viewed in the second direction, the plurality of first semiconductor elements and the plurality of second semiconductor elements overlap each other, Each of the plurality of first connection members extends along the second direction when viewed in the thickness direction, 21. The semiconductor device according to claim 20, wherein each of the plurality of second connection members extends along the second direction when viewed in the thickness direction.

22. When viewed in the second direction, the first element and the third element overlap each other, the third element has the shortest shortest conduction path to the first power terminal among the plurality of second semiconductor elements; 22. The semiconductor device of claim 21, wherein one of the one or more second rectifying elements is disposed between an edge of the third portion that is closer to the first power terminal in the first direction and the third element, as viewed in the thickness direction.

23. the third pad portion includes a slit extending in the first direction as viewed in the thickness direction and a pair of separation portions separated in the second direction by the slit, The semiconductor device according to claim 22 , wherein each of the pair of isolation portions overlaps with the third portion when viewed in the second direction.

24. each of the plurality of first semiconductor elements and each of the plurality of second semiconductor elements is a MOSFET; 24. The semiconductor device according to claim 11, wherein the one or more first rectifying elements and the one or more second rectifying elements are Schottky barrier diodes.

Images