JP6898588B2 - Semiconductor device - Google Patents

Description

The present invention relates to a semiconductor device having a semiconductor element.

When a semiconductor device having a semiconductor element is energized, the semiconductor element generates heat. Therefore, in order to prevent malfunction of the semiconductor element due to heat generation of the semiconductor element, a semiconductor device having a structure suitable for heat dissipation has been conventionally proposed.

Patent Document 1 and Patent Document 2 describe a first semiconductor element, a second semiconductor element, a first conductive member electrically connected to the positive electrode of a DC power supply (or a capacitor module), and a DC power supply (or DC power supply). Disclosed is a semiconductor device including a second conductive member electrically connected to the negative electrode of a condenser unit) and a third conductive member connected to an output terminal connected to an AC power load. .. The first member constitutes a DC input path and the second member constitutes a DC output path. In addition, the third member constitutes an AC path. The first member and the second member are arranged in parallel, and the third member is arranged between the first member and the second member arranged in parallel. Therefore, one side surface of the first member and one side surface of the third member are arranged facing each other with a predetermined gap, and one side surface of the second member and the other side surface of the third member are predetermined. Arranged face-to-face with a gap. The first semiconductor element is joined between one side surface of the first member facing each other and one side surface of the third member, and the second semiconductor element is one side surface of the second member facing each other and one side surface of the third member. It is joined between the other sides of the third member. Further, the lower surface of each member is brought into contact with the cooling device via the insulating sheet.

According to the semiconductor devices described in Patent Document 1 and Patent Document 2, since the first semiconductor element and the second semiconductor element are sandwiched between the side surfaces of the two members, the heat of these semiconductor elements generated during energization is 2. The heat is dissipated to the cooling device through one member. By transferring heat to the two members, the heat transfer area is expanded, so the heat dissipation efficiency is improved.

Japanese Unexamined Patent Publication No. 2013-233042 Japanese Unexamined Patent Publication No. 2007-067084

(Problems to be solved by the invention)
According to the semiconductor devices described in Patent Document 1 and Patent Document 2, a third member which is an AC path between a first member constituting a DC input path and a second member constituting a DC output path. Is intervened, so that the DC input path and the DC output path are separated by the amount that sandwiches the AC path. Therefore, the first member and the second member cannot be brought close to each other, and therefore the parasitic inductance of these members cannot be reduced. Further, since the semiconductor element is interposed between the first member and the third member and between the second member and the third member, these are as much as the semiconductor element is interposed. The distance between the members must be increased, which also makes it impossible to reduce the parasitic inductance of these members.

When the parasitic inductance in the semiconductor device is large, there is a concern that noise may be generated, and the semiconductor element may be damaged by a large surge voltage. Therefore, an object of the present invention is to provide a semiconductor device having high heat dissipation efficiency and further reduced parasitic inductance.

The semiconductor device (1) according to the present invention includes a first semiconductor element (36), a second semiconductor element (37), a first conductive member (31), a second conductive member (32), and a third conductive member. (33), a fourth conductive member (34), and a cooling device (4) are provided.

The first semiconductor element and the second semiconductor element are one main surface on which the first electrode (D) is formed and a surface opposite to the one main surface on which the second electrode (S) is formed. It has the other main surface. The first conductive member is formed of a metal having electrical conductivity and thermal conductivity, and is the same as the first semiconductor bonding surface (313a) to which one main surface of the first semiconductor element is bonded and the first semiconductor bonding surface. It has a contact surface (313b) that faces in a direction and a first heat dissipation surface (316) that faces in a direction different from that of the first semiconductor junction surface. The second conductive member is formed of a metal having electrical conductivity and thermal conductivity, and is joined to the other main surface of the first semiconductor element joined to the first semiconductor joint surface of the first conductive member. It has a portion (323) and a second heat radiating surface (322a) facing the same direction as the first heat radiating surface. The third conductive member is formed of a metal having electrical conductivity and thermal conductivity, faces the same direction as the first semiconductor bonding surface, and is bonded to one main surface of the second semiconductor element (second semiconductor bonding surface). 333) and the facing surface (334) which is a surface facing in the direction opposite to the second semiconductor bonding surface and which is in face-to-face contact with the contact surface via the sheet-shaped insulating member (8) are the same as the first heat radiation surface. It has a third heat radiation surface (336) facing in the direction, and is arranged adjacent to the first conductive member via an insulating member. The fourth conductive member is formed of a metal having electrical conductivity and thermal conductivity, and is joined to the other main surface of the second semiconductor element joined to the second semiconductor joint surface of the second conductive member. It has a portion (343) and a fourth heat radiating surface (342a) facing the same direction as the first heat radiating surface. The cooling device has a cooling surface (41) that comes into surface contact with the first heat radiation surface, the second heat radiation surface, the third heat radiation surface, and the fourth heat radiation surface.

According to the semiconductor device according to the present invention, one main surface of the first semiconductor element is bonded to the first conductive member and the other main surface is bonded to the second conductive member. Further, one main surface of the second semiconductor element is bonded to the third conductive member, and the other main surface is bonded to the fourth conductive member. Therefore, the heat generated by the operation of each semiconductor element is transferred from both main surfaces of each semiconductor element to the cooling surface of the cooling device via different members. Therefore, the heat transfer area is large, and therefore the heat dissipation efficiency is improved.

Further, the first conductive member to which the first semiconductor element is bonded and the third conductive member to which the second semiconductor element is bonded are arranged adjacent to each other via a sheet-shaped insulating member. Therefore, the path of the current flowing through the first conductive member and reaching the first semiconductor element and the path of the current flowing through the third conductive member and reaching the second semiconductor element can be adjacent to each other. Therefore, for example, the current flowing through the first conductive member is set in the DC input path, the current flowing through the third conductive member is set in the DC output path, and the direction of the current flowing through the first conductive member and the current flowing through the third conductive member are set. By setting the direction of the current in the opposite direction, the parasitic inductance of these members can be reduced.

As described above, according to the present invention, it is possible to provide a semiconductor device having high heat dissipation efficiency and further reduced parasitic inductance.

Further, according to the present invention, the first semiconductor bonding surface of the first conductive member to which one main surface of the first semiconductor element is bonded and the third conductive member to which one main surface of the second semiconductor element is bonded. The second semiconductor junction surface of is facing the same direction. Further, the contact surface of the first conductive member, in which the facing surfaces of the third conductive member are in face-to-face contact with each other via the insulating member, faces the same direction as the first semiconductor joint surface and the second semiconductor joint surface. Therefore, the joining of the first semiconductor element to the first conductive member, the joining of the second semiconductor element to the third conductive member, the joining of the second conductive member to the first semiconductor element, and the fourth conductivity to the second semiconductor element. The joining of the members and the assembly of the third conductive member with respect to the first conductive member can all be carried out from the same direction. As a result, unidirectional assembly of the semiconductor device is realized. By realizing such one-way assembly, the productivity of the semiconductor device can be improved.

In the present invention, the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member all have electrical conductivity (property to conduct electricity) and thermal conductivity (property to conduct heat). Formed of metal. Preferably, each of the above members is made of a metal having excellent electrical conductivity and thermal conductivity. Each of the above members is preferably formed of copper, which is a metal having excellent electrical and thermal conductivity.

Further, the first conductive member, the second conductive member, the third conductive member, and the fourth conductive member may have a shape so as to have a large heat transfer area. For example, each of these members may have a portion formed in a lump shape or a block shape instead of a linear shape. According to this, the heat dissipation efficiency of the semiconductor element is further improved, and it contributes to the reduction of the parasitic inductance.

Further, in the present invention, the first heat radiation surface of the first conductive member, the second heat radiation surface of the second conductive member, the third heat radiation surface of the third conductive member, and the fourth heat radiation surface of the fourth conductive member are on the same plane. It should be formed in. Further, the first heat radiation surface, the second heat radiation surface, the third heat radiation surface, and the fourth heat radiation surface may be in surface contact with the cooling surface of the cooling device via the sheet-shaped insulating member (9). According to this, when the cooling surface is the surface of the conductive metal, it is possible to prevent a short circuit between the conductive members via the cooling surface. Further, when each conductive member is brought into contact with the cooling surface of the cooling device via one sheet-shaped insulating member, each conductive member is brought into contact with the cooling surface of the cooling device via a plurality of insulating sheets. In comparison, the heat dissipation efficiency can be further improved.

Further, the semiconductor device according to the present invention may be formed of a metal having electrical conductivity and thermal conductivity, and may include a conductive connecting member (35) that electrically connects the second conductive member and the third conductive member. .. Then, the first conductive member is electrically connected to either the positive electrode or the negative electrode of the power supply (V), and the fourth conductive member is electrically connected to either the positive electrode or the negative electrode of the power supply to be conductive. The sex connecting member may be electrically connected to the power load (M).

According to this, for example, when the positive electrode of the DC power supply is electrically connected to the first conductive member and the negative electrode of the DC power supply is electrically connected to the fourth conductive member, the positive electrode of the DC power supply to the first conductive member A current flows through the second conductive member, and a current flows through the second conductive member via the first semiconductor element. The current flowing through the second conductive member flows to the conductive connecting member, and the current is input to the conductive connecting member or the power load. That is, the first conductive member and the second conductive member form a DC input path. Further, the current output from the electric power load flows through the conductive connecting member, and further flows from the conductive connecting member to the third conductive member. The current flowing through the third conductive member flows to the fourth conductive member via the second semiconductor element, and the current returns from the fourth conductive member to the negative electrode of the power supply. That is, the third conductive member and the fourth conductive member form a DC output path. Therefore, the direction of the current flowing through the first conductive member, which is the DC input path, and the direction of the current flowing through the third conductive member, which is the DC output path, can be set to be opposite to each other, thereby reducing the parasitic inductance. Can be done.

In this case, the second conductive member has a second heat radiation surface and a heat radiation portion (322) having a mounting surface (322b) facing in the direction opposite to the second heat radiation surface, and the conductive connecting member is mounted. It is preferable to have a main body portion (351) which is mounted on the surface and connected to the heat radiating portion, and a connecting piece portion (352) which extends from the main body portion and is connected to the third conductive member.

Further, the first semiconductor bonding surface and the contact surface of the first conductive member may be formed in the order of the contact surface and the first semiconductor bonding surface from the rear to the front in a predetermined first direction. The position where the conductive connecting member is connected to the third conductive member is forward in the first direction from the position where one main surface of the second semiconductor element is joined to the second semiconductor joint surface of the third conductive member. It is good to be. In this case, it is preferable that either the positive electrode or the negative electrode of the power supply is connected to the first conductive member so that the current flows forward in the first conductive member in the first direction.

According to this, when the first semiconductor element is in the conductive state and the second semiconductor element is in the non-conducting state, a current flows forward in the first conductive member, for example, in the first direction, and the first semiconductor element. Further, a current flows from the first semiconductor element to the second conductive member and the conductive connecting member, and the current is input to the power load. On the other hand, when the second semiconductor element is in the conductive state and the first semiconductor element is in the non-conducting state, the current output from the power load side and flowing to the conductive connecting member is from the conductive connecting member to the third conductive member. And then flows to the fourth conductive member via the second semiconductor element. Here, the position where the conductive connecting member is connected to the third conductive member is in the first direction from the position where one main surface of the second semiconductor element is joined to the second semiconductor joint surface of the third conductive member. Is ahead in. Therefore, the current flowing from the conductive connecting member to the third conductive member flows rearward in the first direction in the third conductive member and reaches the second semiconductor element. As described above, the direction of the current flowing through the first conductive member (front) and the direction of the current flowing through the third conductive member (rear) are opposite directions. Since the first conductive member and the third conductive member in which the current flows in opposite directions are arranged adjacent to each other via the insulating member, the parasitic inductance of these members can be reduced.

Further, the semiconductor device according to the present invention further includes a third semiconductor element (2) which is connected to a power source and has a first connection terminal (223, 225, 227) and a second connection terminal (224, 226, 228). The first conductive member has a first mounting surface (315) on which the first connection terminal is mounted, and the fourth conductive member has a second mounting surface (342b) on which the second connection terminal is mounted. The first connection terminal is welded to the first mounting surface, and the second connection terminal is welded to the second mounting surface. According to this, when incorporating the third semiconductor element into the semiconductor device, the first connection terminal is joined to the first conductive member by, for example, laser welding, and the second connection terminal is joined to the fourth conductive member by, for example, laser welding. Laser. By welding and joining the third semiconductor element to each conductive member in this way, it is possible to increase the dimensional tolerance of the joining position as compared with the case of joining with screws, for example. Therefore, the design man-hours of the semiconductor device and the productivity of the semiconductor device can be improved, and the cost can be reduced because the fastening member is not required.

The third semiconductor element is preferably a capacitor. Further, the first semiconductor element and the second semiconductor element are preferably transistors. According to this, the semiconductor device according to the present invention can be applied to an inverter using a capacitor and a transistor.

It is a perspective view of the semiconductor device which concerns on embodiment. It is a top view of the semiconductor device which concerns on embodiment. It is a perspective view of a power module. It is a right side view of a power module. It is a front view of a power module. It is a perspective view which shows the 1st conductive block member. It is a perspective view of the first assembly structure. It is a front view of the first assembly structure. It is a perspective view of the assembly structure of the 3rd conductive member and the conductive connection member. It is a right side view of the assembly structure of the 3rd conductive member and the conductive connection member. It is a perspective view of the 2nd assembly structure. It is a front view of the 2nd assembly structure. It is a circuit diagram which shows the inverter circuit which comprises the semiconductor device which concerns on embodiment. It is a figure which shows the DC input path in a power module. It is a figure which shows the DC output path in a power module.

Hereinafter, the semiconductor device according to the embodiment of the present invention will be described with reference to the drawings. In this embodiment, a semiconductor device used as an inverter circuit of a three-phase DC brushless motor will be described. FIG. 1 is a perspective view of the semiconductor device 1 according to the present embodiment, and FIG. 2 is a plan view of the semiconductor device 1. When the structure of the semiconductor device 1 is described using the directions, the length direction, the width direction, and the height direction orthogonal to each other are defined as shown in FIGS. 1 and 2. Further, one in the length direction is defined as front, the other is defined as rear, one in the width direction is defined as right, the other is defined as left, one in the height direction is defined as upward, and the other is defined as downward. The length direction, width direction, and height direction in each figure are the same direction. The length direction corresponds to the first direction of the present invention.

As shown in FIGS. 1 and 2, the semiconductor device 1 includes a capacitor module 2, a first power module 3A, a second power module 3B, a third power module 3C, and a cooling device 4.

The cooling device 4 is formed in a flat plate shape that is long in the length direction and the width direction. A cooling water passage is formed inside the cooling device 4, and the cooling water flows through the cooling water passage. The semiconductor device 1 is cooled by transferring heat to the cooling water in the cooling passage.

The condenser module 2 and the power modules 3A, 3B, and 3C are arranged on the upper surface 41, which is a surface facing upward in the height direction of the cooling device 4. The upper surface 41 corresponds to the cooling surface of the present invention. The power modules 3A, 3B, and 3C are aligned and arranged along the width direction. The capacitor module 2 is arranged at a rear position in the length direction of each of the power modules 3A, 3B, and 3C.

The capacitor module 2 includes a case main body 21, a capacitor (not shown) arranged inside the case main body 21, and a plurality of connection terminals (positive electrode terminal 221 and negative electrode terminal 222, first) attached to the case main body 21. Connection terminals 223, 225, 227 and second connection terminals 224, 226, 228) are provided. The positive electrode terminal 221 and the negative electrode terminal 222 extend rearward from the rear end of the case body 21, and the first connection terminal and the second connection terminal (223 to 228) face forward from the front end of the case body 21. Will be extended.

The first power module 3A, the second power module 3B, and the third power module 3C have the same structure. In the following description, these power modules 3A, 3B, and 3C are collectively referred to as a power module 3 as necessary.

FIG. 3 is a perspective view of the power module 3, FIG. 4 is a right side view of the power module 3 as viewed from the right side, and FIG. 5 is a front view of the power module 3 as viewed from the front. As shown in FIGS. 3 to 5, the power module 3 includes a first conductive member 31, a second conductive member 32, a third conductive member 33, a fourth conductive member 34, a conductive connecting member 35, and the like. It includes a pair of first transistors 36, 36 and a pair of second transistors 37, 37.

FIG. 6 is a perspective view showing the first conductive member 31 included in the power module 3. As shown in FIG. 6, the first conductive member 31 is generally formed in a substantially rectangular parallelepiped shape (block shape). The first conductive member 31 is made of a metal having excellent electrical conductivity and thermal conductivity, for example, copper.

The first conductive member 31 includes a front surface 311 facing forward, a rear surface 312 facing backward, a right surface 313 facing right, a left surface 314 facing left, an upper surface 315 facing upward, and a lower surface facing downward. It has 316. Further, a chamfered surface 317 is continuously formed along the height direction at the boundary portion between the right surface 313 and the rear surface 312. Here, the right surface 313 of the first conductive member 31 is divided into a right front surface 313a formed on the front side and a right rear surface 313b formed on the rear side. The right front surface 313a and the right rear surface 313b are both surfaces facing the same direction (to the right) and are located on the same plane. The right front surface 313a corresponds to the first semiconductor bonding surface of the present invention, and the right rear surface 313b corresponds to the contact surface of the present invention. As can be seen from FIG. 6, the right rear surface 313b (contact surface) and the right front surface 313a are formed in this order toward the front in the length direction. Further, the lower surface 316 is a surface facing a direction different from the right front surface 313a, which is the first semiconductor bonding surface. The lower surface 316 corresponds to the first heat radiation surface of the present invention.

A pair of first transistors 36, 36 are joined to the right front surface 313a of the first conductive member 31. The pair of first transistors 36, 36 is, for example, a MOSFET, and has one main surface and the other main surface on the opposite side. A drain electrode as a first electrode is formed on one main surface, a source electrode as a second electrode, and a gate electrode as a control electrode are formed on the other main surface. Then, one of the main surfaces on which the drain electrodes of the pair of first transistors 36, 36 are formed is joined to the right front surface 313a of the first conductive member 31 via a conductive metal such as solder.

The second conductive member 32 is attached to the other main surface of the pair of first transistors 36, 36 joined to the right front surface 313a of the first conductive member 31. Therefore, the second conductive member 32 is assembled to the first conductive member 31 via the pair of first transistors 36, 36. The second conductive member 32 is made of a metal having excellent electrical conductivity and thermal conductivity, for example, copper.

FIG. 7 is a perspective view showing an assembled structure of the first conductive member 31 and the second conductive member 32 (hereinafter, may be referred to as a first assembled structure). Further, FIG. 8 is a front view of the first assembled structure viewed from the front. As shown in FIGS. 7 and 8, the second conductive member 32 includes a main body portion 321 and a heat radiating portion 322, and a pair of first joint portions 323 and 323.

The main body portion 321 is formed in a plate shape long in the length direction and the height direction, and is arranged on the right side of the right front surface 313a of the first conductive member 31 at a predetermined interval. A pair of first joint portions 323 and 323 are provided at the upper end portion of the main body portion 321 and a heat radiating portion 322 is provided at the lower end portion. The pair of first junctions 323 and 323 extend to the left from the upper end of the main body 321 and have a conductive metal such as solder on the other main surface of the pair of first transistors 36, 36 at the tip surface thereof. It is joined via. Further, the heat radiating portion 322 provided at the lower end portion of the main body portion 321 extends from the lower end portion of the main body portion 321 toward the right. The heat radiating portion 322 is formed in a plate shape that is long in the width direction and the length direction. Further, as can be seen from FIG. 8, the heat radiating portion 322 has a lower surface 322a facing downward and an upper surface 322b facing in the opposite direction (upward) to the lower surface 322a. The lower surface 322a of the heat radiating portion 322 faces the same direction as the lower surface 316 of the first conductive member 31, and its height direction coincides with the height direction position of the lower surface 316 of the first conductive member 31. The lower surface 322a of the heat radiating portion 322 corresponds to the second heat radiating surface of the present invention. The upper surface 322b of the heat radiating portion 322 corresponds to the mounting surface of the present invention.

FIG. 9 is a perspective view showing a third conductive member 33 and a conductive connecting member 35 included in the power module 3. Further, FIG. 10 is a right side view of the third conductive member 33 and the conductive connecting member 35 as viewed from the right. As is well shown in FIG. 9, the third conductive member 33 also has a rectangular parallelepiped shape (block shape) like the first conductive member 31, and has a front surface 331 facing forward, a rear surface 332 facing backward, and facing right. It has a right side 333, a left side 334 facing left, an upper surface 335 facing upward, and a lower surface 336 facing downward. The right surface 333 of the third conductive member 33 is a surface facing the same direction as the right front surface 313a of the first conductive member 31. The right surface 333 corresponds to the second semiconductor junction surface of the present invention. Further, the lower surface 336 of the third conductive member 33 is a surface facing the same direction as the lower surface 316 of the first conductive member 31. The lower surface 336 corresponds to the third heat radiation surface of the present invention. Further, a chamfered surface 337 is continuously formed along the height direction at the boundary portion between the left surface 334 and the rear surface 332. Like the first conductive member 31, the third conductive member 33 is also made of a metal having excellent electrical conductivity and thermal conductivity, for example, copper.

The conductive connecting member 35 is formed in a flat plate shape long in the width direction and the length direction, and is made of a metal having excellent electrical conductivity and thermal conductivity, for example, copper. The conductive connecting member 35 is arranged on the right front side of the third conductive member 33. Further, the conductive connecting member 35 has a flat plate-shaped main body portion 351 that is rectangular in a plan view, and a pair of connecting piece portions 352 and 352 extending from the left rear portion of the main body portion 351. One connecting piece 352 is joined to the right side portion of the front surface 331 of the third conductive member 33, and the other connecting piece portion 352 is joined to the right side 333 front portion of the third conductive member 33. The conductive connecting member 35 is electrically connected to the third conductive member 33 by the pair of connecting piece portions 352 and 352. Further, as shown in FIG. 10, the conductive connecting member 35 is attached to the third conductive member 33 at a position closer to the lower side in the height direction. However, the height direction position of the lower surface 351a of the main body 351 of the conductive connecting member 35 attached to the third conductive member 33 is located above the height direction position of the lower surface 336 of the third conductive member 33. ..

A pair of second transistors 37, 37 are joined to the right surface 333 of the third conductive member 33. The pair of second transistors 37, 37 are preferably the same transistors as the pair of first transistors 36, 36. The pair of second transistors 37, 37 have one main surface and the other main surface on the opposite side. A drain electrode as a first electrode is formed on one main surface, and a source electrode as a second electrode and a gate electrode as a control electrode are formed on the other main surface. Then, one of the main surfaces on which the drain electrodes of the pair of second transistors 37 and 37 are formed is joined to the right surface 333 of the third conductive member 33 via a conductive metal such as solder.

The fourth conductive member 34 is attached to the other main surface of the pair of second transistors 37, 37 attached to the right surface 333 of the third conductive member 33. Therefore, the fourth conductive member 34 is attached to the third conductive member 33 via the pair of second transistors 37, 37. The fourth conductive member 34 is made of a metal having excellent electrical conductivity and thermal conductivity, for example, copper.

FIG. 11 is a perspective view of an assembled structure (hereinafter, may be referred to as a second assembled structure) of the third conductive member 33, the fourth conductive member 34, and the conductive connecting member 35. Further, FIG. 12 is a front view of the second assembled structure viewed from the front. As shown in FIGS. 11 and 12, the fourth conductive member 34 includes a main body portion 341, a heat radiating portion 342, and a pair of second joint portions 343 and 343.

The main body portion 341 is formed in a flat plate shape that is long in the length direction and the height direction, and is arranged on the right side of the right surface 333 of the third conductive member 33 at a predetermined interval. A pair of second joints 343 and 343 are provided at the upper end of the main body 341, and a heat dissipation portion 342 is provided at the lower end. The pair of second junctions 343 and 343 extend to the left from the upper end of the main body 341, and at the tip surface thereof, a conductive metal such as solder is formed on the other main surface of the pair of second transistors 37 and 37. It is joined via. Further, the heat radiating portion 342 provided at the lower end portion of the main body portion 341 extends from the lower end portion of the main body portion 341 toward the right and downward, and is formed in a rectangular parallelepiped shape (block shape). The lower surface 342a of the heat radiating portion 342 is a surface facing the same direction (downward) as the lower surface 336 of the third conductive member 33. Further, as can be seen from FIG. 12, the height direction position of the lower surface 342a of the heat radiating portion 342 coincides with the height direction position of the lower surface 336 of the third conductive member 33. The lower surface 342a of the heat radiating portion 342 corresponds to the fourth heat radiating surface of the present invention.

The power module 3 is obtained by combining the first assembly structure as shown in FIGS. 7 and 8 and the second assembly structure as shown in FIGS. 11 and 12, and the power modules 3 are shown in FIGS. It is formed as shown in 5. In this case, as shown in FIGS. 4 and 5, the lower surface 351a of the main body 351 of the conductive connecting member 35 connected to the third conductive member 33 is attached to the first conductive member 31. The conductive connecting member 35 is placed on the upper surface 322b of the heat radiating portion 322 of the second conductive member 32 so as to make face-to-face contact with the upper surface 322b of the heat radiating portion 322. Then, in that state, the lower surface 351a of the main body 351 of the conductive connecting member 35 and the upper surface 322b of the heat radiating portion 322 of the second conductive member 32 are joined by a joining means such as welding. By such joining, the first assembly structure and the second assembly structure are assembled.

When the first assembly structure and the second assembly structure are assembled as described above, as shown well in FIGS. 4 and 5, the lower surface 316 of the first conductive member 31 and the second conductive member 32 The lower surface 322a of the heat radiating portion 322, the lower surface 336 of the third conductive member 33, and the lower surface 342a of the heat radiating portion 342 of the fourth conductive member 34 face in the same direction (lower surface), and the positions of these surfaces in the height direction are Match. That is, the lower surface 316 of the first conductive member 31, the lower surface 322a of the heat radiating portion 322 of the second conductive member 32, the lower surface 336 of the third conductive member 33, and the lower surface 342a of the heat radiating portion 342 of the fourth conductive member 34 are on the same plane. Located in. These surfaces located on the same plane are adhered to the upper surface 41 of the cooling device 4 via the insulating sheet 9.

Further, as shown in FIG. 5, the left surface 334 of the third conductive member 33 is a surface facing in the direction opposite to the right surface 333 (second semiconductor joint surface) of the third conductive member 33. The left surface 334 faces the right rear surface 313b (contact surface) of the first conductive member 31. Both sides (334, 313b) facing each other are adhered to each other via the insulating sheet 8. As a result, the first conductive member 31 and the third conductive member 33 are insulated and arranged next to each other. The left surface 334 of the third conductive member 33 corresponds to the opposing surface of the present invention.

As shown in FIG. 1, the first power module 3A, the second power module 3B, and the third power module 3C having the above configuration are arranged on the upper surface 41 of the cooling device 4 so as to be aligned in the width direction. Further, the power modules 3A, 3B, 3C are arranged so that the front surface 311 of the first conductive member 31 and the front surface 331 of the third conductive member 33 included in the power modules 3A, 3B, 3C face forward in the length direction. It is arranged on the cooling device 4.

Further, as shown in FIGS. 1 and 2, a current sensor 5 is connected to each of the power modules 3A, 3B, and 3C. The current sensor 5 includes first input / output terminals 51A, 51B, 51C and second input / output terminals 52A, 52B, 52C corresponding to the power modules 3A, 3B, 3C, respectively. Then, the current sensor 5 has the magnitude of the current flowing between the first input / output terminal 51A corresponding to the first power module 3A and the second input / output terminal 52A, and the first input / output corresponding to the second power module 3B. The magnitude of the current flowing between the terminal 51B and the second input / output terminal 52B, and the magnitude of the current flowing between the first input / output terminal 51C and the second input / output terminal 52C corresponding to the third power module 3C. , Each is configured to be detectable.

The current sensor 5 is arranged on the upper surface of the cooling device 4 and on the front side of each of the power modules 3A, 3B, and 3C. The first input / output terminals 51A, 51B, and 51C of the current sensor 5 are placed on the upper surface of the main body 351 of the conductive connection member 35 of the power modules 3A, 3B, and 3C, respectively, and are joined by screwing or welding. By means, it is electrically connected to the conductive connecting member 35. The second input / output terminals 52A, 52B, and 52C of the current sensor 5 project forward from the cooling device 4, respectively. The second input / output terminal 52A corresponding to the first power module 3A is connected to the U-phase coil of the three-phase DC brushless motor via an electric wire (output line). The second input / output terminal 52B corresponding to the second power module 3B is connected to the V-phase coil of the three-phase DC brushless motor via an electric wire (output line). The second input / output terminal 52C corresponding to the third power module 3C is connected to the W-phase coil of the three-phase DC brushless motor via an electric wire (output line).

Further, the condenser module 2 is arranged on the upper surface of the cooling device 4 at a position behind each power module 3. The positive electrode terminal 221 of the capacitor module 2 is connected to the positive electrode of the power supply, and the negative electrode terminal 222 is connected to the negative electrode of the power supply. Further, the first connection terminal 223 of the capacitor module 2 is mounted on the upper surface 315 of the first conductive member 31 of the first power module 3A, and the second connection terminal 224 dissipates heat from the fourth conductive member 34 of the first power module 3A. It is placed on the upper surface 342b of the portion 342. The first connection terminal 225 of the capacitor module 2 is mounted on the upper surface 315 of the first conductive member 31 of the second power module 3B, and the second connection terminal 226 is the heat dissipation portion 342 of the fourth conductive member 34 of the second power module 3B. It is placed on the upper surface 342b of the above. The first connection terminal 227 of the capacitor module 2 is mounted on the upper surface 315 of the first conductive member 31 of the third power module 3C, and the second connection terminal 228 is the heat dissipation portion 342 of the fourth conductive member 34 of the third power module 3C. It is placed on the upper surface 342b of the above. Each connection terminal placed on the upper surface (315, 342b) of each conductive member (31, 34) is electrically connected to the upper surface of the conductive member on which it is placed by laser welding. As a result, the power modules 3A, 3B, and 3C are electrically connected to the capacitor module 2. The upper surface 315 of the first conductive member 31 corresponds to the first mounting surface of the present invention. The upper surface 342b of the heat radiating portion 342 of the fourth conductive member 34 corresponds to the second mounting surface of the present invention.

FIG. 13 is a circuit diagram showing an inverter circuit configured by the semiconductor device 1 having the above configuration. As shown in FIG. 13, the positive electrode line PL is connected to the positive electrode VP of the power supply V, and the negative electrode line NL is connected to the negative electrode VN of the power supply V. The positive electrode terminal 221 of the capacitor module 2 is connected to the positive electrode line PL, and the negative electrode terminal 222 of the capacitor module 2 is connected to the negative electrode line NL.

Further, the first conductive member 31 of the first power module 3A is connected to the capacitor module 2 and the positive electrode VP of the power supply V via the first connection terminal 223 of the capacitor module 2 and the positive electrode line PL, and is connected to the positive electrode VP of the power supply V. The first conductive member 31 is connected to the capacitor module 2 and the positive electrode VP of the power supply V via the first connection terminal 225 of the capacitor module 2 and the positive electrode line PL, and the first conductive member 31 of the third power module 3C is a capacitor. It is connected to the capacitor module 2 and the positive electrode VP of the power supply V via the first connection terminal 227 of the module 2 and the positive electrode line PL.

Further, the first conductive member 31 of each power module 3A, 3B, 3C is connected to the drain electrodes D, D of the pair of first transistors 36, 36, and the second conductive member 32 of each power module 3A, 3B, 3C is connected. Is connected to the source electrodes S, S of the pair of first transistors 36, 36. The upper arm of the inverter circuit is composed of the first conductive member 31, the pair of first transistors 36, 36, and the second conductive member 32 of each of the power modules 3A, 3B, and 3C.

Further, the fourth conductive member 34 of the first power module 3A is connected to the capacitor module 2 and the negative electrode VN of the power supply V via the second connection terminal 224 of the capacitor module 2 and the negative electrode line NL, and the second power module 3B The fourth conductive member 34 is connected to the capacitor module 2 and the negative electrode VN of the power supply V via the second connection terminal 226 of the capacitor module 2 and the negative electrode line NL, and the fourth conductive member 34 of the third power module 3C is a capacitor. It is connected to the capacitor module 2 and the negative electrode VN of the power supply V via the second connection terminal 228 of the module 2 and the negative electrode line NL.

Further, the fourth conductive member 34 of each power module 3A, 3B, 3C is connected to the source electrodes S, S of the pair of second transistors 37, 37, and the third conductive member 33 of each power module 3A, 3B, 3C is connected. Is connected to the drain electrodes D, D of the pair of second transistors 37, 37. Third conductive member of each power module 3A, 3B, 3C 33. The lower arm of the inverter circuit is composed of the pair of second transistors 37, 37 and the fourth conductive member 34.

The second conductive member 32 and the third conductive member 33 of each of the power modules 3A, 3B, and 3C are both connected to the conductive connecting member 35. The conductive connecting member 35 of the first power module 3A is connected to the U-phase coil of the three-phase DC brushless motor M via the first output line 71, and the conductive connecting member 35 of the second power module 3B is the second. It is connected to the V-phase coil of the three-phase DC brushless motor M via the output line 72, and the conductive connecting member 35 of the third power module 3C is connected to the W phase of the three-phase DC brushless motor M via the third output line 73. Connected to the coil. In this way, the conductive connecting members 35 of the power modules 3A, 3B, and 3C are all connected to the three-phase DC brushless motor M, which is a power load.

The pair of first transistors 36, 36 and the pair of second transistors 37, 37 provided in each of the power modules 3A, 3B, and 3C function as switching elements. In this case, when a control signal is input from a control board (not shown) to the gate electrodes G of the transistors 36 and 37 in a predetermined pattern, the transistors 36 and 37 are switched. Further, in the present embodiment, the pair of first transistors 36, 36 included in one power module operate at the same time, and the pair of second transistors 37, 37 included in one power module operate at the same time. That is, the ON operation timing and the OFF operation timing of the pair of first transistors 36, 36 included in one power module match, and the ON operation timing and OFF operation timing of the pair of second transistors 37, 37 included in one power module are the same. Match.

When the first transistor 36, 36 or the second transistor 37, 37 is turned on, the drain and the source are brought into a conductive state. When the first transistor 36, 36 or the second transistor 37, 37 is turned off, the drain and source are brought into a non-conducting state. Therefore, when the first transistors 36, 36 are turned on, a current can be passed through the upper arm including the first transistors 36, 36, and when the first transistors 36, 36 are turned off, the current can flow. No current can flow through the upper arm including the first transistors 36, 36. Further, when the second transistors 37, 37 are turned on, a current can be passed through the lower arm including the second transistors 37, 37, and when the second transistors 37, 37 are turned off, the current can flow. No current can flow through the lower arm including the second transistors 37, 37.

In the inverter circuit shown in FIG. 13, as an example, the first transistors 36, 36 of the first power module 3A and the second transistors 37, 37 of the third power module 3C are turned on, and the other transistors are turned off. The current flow in the inverter circuit will be described with respect to the case. In this case, a current flows through the upper arm of the first power module 3A and the lower arm of the third power module 3C. Therefore, the current flowing from the positive electrode VP of the power supply V to the positive electrode line PL and smoothed by the capacitor module 2 is the first conductive member 31 forming the upper arm of the first power module 3A and the pair of first transistors 36, 36. , The second conductive member 32 flows in this order, and further flows from the second conductive member 32 to the conductive connecting member 35 of the first power module 3A. The current flowing through the conductive connecting member 35 of the first power module 3A flows to the first output line 71 via a current sensor 5 (not shown in FIG. 13). Then, a current is input from the first output line 71 to the U-phase coil of the three-phase DC brushless motor M. In this way, a current is supplied from the power supply V side to the three-phase DC brushless motor M (power load) side via the power module 3 (first power module 3A).

Further, the current output from the W-phase coil of the three-phase DC brushless motor M flows to the conductive connecting member 35 of the third power module 3C via the third output line 73 and the current sensor 5 (not shown), and further. The current flows through the third conductive member 33, the second transistors 37, 37, and the fourth conductive member 34, which form the lower arm of the third power module 3C, in this order. Then, the current flowing through the fourth conductive member 34 of the third power module 3C returns to the negative electrode VN of the power supply V via the negative electrode line NL. In this way, a current flows from the three-phase DC brushless motor M (power load) side to the power supply V side via the power module 3 (third power module 3C).

Further, as another example, in the case where the first transistors 36 and 36 of the second power module 3B and the second transistors 37 and 37 of the first power module 3A are turned on and the other transistors are turned off, the inverter The flow of current in the circuit will be described. In this case, a current flows through the upper arm of the second power module 3B and the lower arm of the first power module 3A. Therefore, the current flowing from the positive electrode VP of the power supply V to the positive electrode line PL and smoothed by the capacitor module 2 is the first conductive member 31 forming the upper arm of the second power module 3B and the pair of first transistors 36, 36. , The second conductive member 32 flows in this order, and further flows from the second conductive member 32 to the conductive connecting member 35 of the second power module 3B. The current flowing through the conductive connecting member 35 of the second power module 3B flows to the second output line 72 via the current sensor 5 (not shown in FIG. 13). Then, a current is input from the second output line 72 to the V-phase coil of the three-phase DC brushless motor M. In this way, a current flows from the power supply V side to the three-phase DC brushless motor M (power load) side via the power module 3 (second power module 3B).

Further, the current output from the U-phase coil of the three-phase DC brushless motor M flows to the conductive connecting member 35 of the first power module 3A via the first output line 71 and the current sensor 5 (not shown), and further. The current flows through the third conductive member 33, the second transistors 37, 37, and the fourth conductive member 34, which form the lower arm of the first power module 3A, in this order. Then, the current flowing through the fourth conductive member 34 of the first power module 3A returns to the negative electrode VN of the power supply V via the negative electrode line NL. In this way, a current flows from the three-phase DC brushless motor M (power load) side to the power supply V side via the power module 3 (first power module 3A).

FIG. 14 is a diagram showing a DC input path of the current in the power module 3 when a current is input from the power supply V side to the three-phase DC brushless motor M side via the power module 3. In this case, the first transistors 36 and 36 are turned on (conducting state), and the second transistors 37 and 37 are turned off (non-conducting state). As shown in FIG. 14, the current from the power supply V side (capacitor module 2 side) flows into the first conductive member 31 from the rear of the first conductive member 31. Here, the right front surface 313a of the first conductive member 31 to which one of the main surfaces of the first transistors 36, 36 is joined is formed on the front side of the first conductive member 31. Further, the right rear surface 313b and the right front surface 313a of the first conductive member 31 are formed in the order of the right rear surface 313b and the right front surface 313a along the front in the length direction. Therefore, the current flowing from the rear of the first conductive member 31 flows forward through the first conductive member 31 via the portion corresponding to the right rear surface 313b of the first conductive member 31 and reaches the right front surface 313a. It leads to a pair of bonded first transistors 36, 36. Then, it flows through the second conductive member 32 via the first transistors 36 and 36. Although the third conductive member 33 is arranged adjacent to the first conductive member 31, the insulating sheet 8 is interposed between the first conductive member 31, so that a current flows from the first conductive member 31 to the third conductive member 33. There is no. The current flowing forward through the first conductive member 31 and flowing into the second conductive member 32 is further transferred from the second conductive member 32 to the conductive connecting member 35 connected to the heat radiating portion 322 of the second conductive member 32. It flows. Then, a current flows from the conductive connecting member 35 to the three-phase DC brushless motor M side via a current sensor 5 (not shown).

FIG. 15 is a diagram showing a DC output path of the current in the power module when a current is output from the three-phase DC brushless motor M side to the power supply V side via the power module 3. In this case, the first transistors 36 and 36 are turned off (non-conducting state), and the second transistors 37 and 37 are turned on (conducting state). As shown in FIG. 15, the current output from the three-phase DC brushless motor M flows through the conductive connecting member 35 after passing through the current sensor 5 (not shown). Since the conductive connecting member 35 is connected to the right front portion of the third conductive member 33, the current flowing through the conductive connecting member 35 then flows into the right front portion of the third conductive member 33. Here, as shown in FIG. 15, at the position where the conductive connecting member 35 is connected to the third conductive member 33 (position A in FIG. 15), one main surface of the pair of second transistors 37, 37 is the first. It is anterior in the length direction from the position (position B in FIG. 15) joined to the right surface 333 of the three conductive members 33. Therefore, the current flowing from the conductive connecting member 35 to the third conductive member 33 flows rearward in the third conductive member 33 and is joined to the right surface 333 of the third conductive member 33. , 37. Then, the current flows to the fourth conductive member 34 via the second transistors 37 and 37, and further, a current flows from the fourth conductive member 34 to the power supply V side (capacitor module 2 side).

As can be seen from FIG. 14, when a current flows from the power supply V side to the three-phase DC brushless motor M side, the current flows forward in the first conductive member 31 of the power module 3. on the other hand. As can be seen from FIG. 15, when a current flows from the three-phase DC brushless motor M side to the power supply V side, the current flows backward in the third conductive member 33 in the power module 3. That is, the direction of the DC input current flowing through the first conductive member 31 and the direction of the DC output current flowing through the third conductive member 33 are opposite. Further, the first conductive member 31 constitutes a current path of the DC input paths before passing through the first transistors 36, 36. On the other hand, the third conductive member 33 constitutes a current path of the DC output paths before passing through the second transistors 37 and 37. Therefore, in the semiconductor device 1 according to the present embodiment, the directions of the current flowing through the current path of the DC input path before passing through the semiconductor element and the direction of the current flowing through the current path of the DC output path before passing through the semiconductor element. Is configured to be in the opposite direction.

The first conductive member 31 and the third conductive member 33 are arranged adjacent to each other via the insulating sheet 8. When the members through which currents flow in opposite directions are arranged adjacent to each other, the parasitic inductance of both members is reduced by the action of the mutual inductance of both members. That is, the semiconductor device 1 according to the present embodiment is configured to be able to reduce the parasitic inductance.

Further, the components of the DC input / output path of the current (first conductive member 31, second conductive member 32, third conductive member 33, fourth conductive member 34, conductive connecting member 35) are not electric wires but block-shaped or It is a plate-shaped member. Therefore, the parasitic inductance is lower than that of the electric wire. Therefore, the parasitic inductance in the semiconductor device 1 can be further reduced.

Further, according to the semiconductor device 1 according to the present embodiment, one main surface of the first transistors 36, 36 is in surface contact with the first conductive member 31, and the other main surface is the first junction of the second conductive member 32. It comes into surface contact with the tip surface of the portion 323. Therefore, the heat generated during the switching operation of the first transistors 36, 36 is transferred to the cooling device 4 via both the first conductive member 31 and the second conductive member 32. In this way, the heat of the first transistors 36, 36 is transferred to the cooling device 4 via the plurality of members, so that the heat transfer area is expanded, and therefore the heat dissipation efficiency is improved.

Further, the first conductive member 31 has a rectangular parallelepiped shape, and the area of the lower surface 316, which is the surface in contact with the cooling device 4, is large. Further, the second conductive member 32 includes a heat radiating portion 322, and the heat radiating portion 322 extends in the length direction and the width direction on the upper surface 41 of the cooling device 4 so that the lower surface 322a in contact with the cooling device 4 becomes large. There is. Therefore, the area where the first conductive member 31 and the second conductive member 32 come into contact with the upper surface 41 (cooling surface) is large, and therefore, the heat of the first transistors 36, 36 is more efficiently transferred to the cooling device 4. As a result, the heat dissipation efficiency is further improved.

Further, according to the semiconductor device 1 according to the present embodiment, one main surface of the second transistors 37, 37 is brought into surface contact with the third conductive member 33, and the other main surface is the second junction of the fourth conductive member 34. The tip surface of the portion 343 is brought into surface contact. Therefore, the heat generated during the switching operation of the second transistors 37 and 37 is transferred to the cooling device 4 via both the third conductive member 33 and the fourth conductive member 34. In this way, the heat of the second transistors 37, 37 is transferred to the cooling device 4 via the plurality of members, so that the heat transfer area is expanded, and therefore the heat dissipation efficiency is improved.

Further, the third conductive member 33 has a rectangular parallelepiped shape, and the area of the lower surface 336, which is the surface in contact with the cooling device 4, is large. Further, the fourth conductive member 34 includes a heat radiating portion 342, and the heat radiating portion 342 extends in the length direction and the width direction on the upper surface 41 of the cooling device 4 so that the lower surface 342a in contact with the cooling device 4 becomes large. There is. Therefore, the area where the third conductive member 33 and the fourth conductive member 34 come into contact with the upper surface 41 (cooling surface) of the cooling device 4 is large, and therefore, the heat of the second transistors 37 and 37 is cooled more efficiently. It can be transmitted to the device 4, and as a result, the heat dissipation efficiency is further improved.

Further, the first conductive member 31, the second conductive member 32, the third conductive member 33, and the fourth conductive member 34 are in contact with the upper surface 41 of the cooling device 4 only through the insulating sheet 9. Therefore, there are few members that hinder heat dissipation between each conductive member and the cooling device 4, and thereby efficiently transfer the heat of the first transistors 36 and 36 and the heat of the second transistors 37 and 37 to the cooling device 4. Can be made to.

Further, according to the semiconductor device 1 according to the present embodiment, one main surface of the first transistors 36, 36 is joined to the right front surface 313a of the first conductive member 31 of the power module 3, and the right surface of the third conductive member 33. One main surface of the second transistors 37, 37 is joined to the 333. Therefore, the first transistors 36, 36 are joined from the right side of the first conductive member 31, and the second transistors 37, 37 are joined from the right side of the third conductive member 33. Further, the second conductive member 32 is joined to the other main surface of the first transistors 36, 36 joined to the first conductive member 31 facing to the right, and the fourth conductive member 34 is the third conductive member 33. It is joined to the other main surface of the second transistors 37, 37, which are joined to the right side, facing to the right. Therefore, the second conductive member 32 is joined to the first transistors 36, 36 from the right side of the first transistors 36, 36, and the fourth conductive member 34 is second from the right side of the second transistors 37, 37. It will be joined to the transistors 37 and 37. Further, the third conductive member 33 is connected to the right rear surface 313b of the first conductive member 31, that is, the surface facing to the right from the right side via the insulating sheet 8. As described above, the first transistors 36, 36 are assembled to the first conductive member 31, the second conductive member 32 is assembled to the first conductors 36, 36, and the second transistors 37, 37 are assembled to the third conductive member 33. Assembling, assembling the fourth conductive member 34 to the second transistors 37, 37, and assembling the third conductive member 33 to the first conductive member 31 are all performed from the right side. That is, one-way assembly is realized. By realizing the one-way assembly in this way, it is possible to automate the production of the semiconductor device 1 and improve the productivity.

Further, according to the semiconductor device 1 according to the present embodiment, the power modules 3A, 3B, and 3C are directly attached to the upper surface 315 of the first conductive member 31 and the upper surface 342b of the heat radiating portion 342 of the fourth conductive member 34. The connection terminals of the capacitor module 2 are welded together. Therefore, the dimensional tolerance of the joining position can be increased as compared with the case where the capacitor modules 2 are joined to the power modules 3A, 3B, and 3C with screws, for example. Therefore, the design man-hours of the semiconductor device 1 and the productivity of the semiconductor device can be improved, and the cost can be reduced because the fastening member is not required.

Further, according to the semiconductor device 1 according to the present embodiment, the heat radiating surfaces (316, 322a, 336, 342a) of each conductive member (31, 32, 33, 34) are cooled via one insulating sheet 9. It is in contact with the upper surface 41 (cooling surface) of the device 4. Therefore, the heat dissipation efficiency is further improved as compared with the conventional structure in which the heat radiating surface comes into contact with the cooling device via the two or more layers of insulating sheets. Further, since the heat dissipation efficiency from each conductive member to the cooling device 4 is improved in this way, for example, the heat of the first transistors 36, 36 is not transferred to the capacitor module 2 side via the contact terminals. Further, since the heat capacity of the conductive member is large, an increase in the terminal temperature can be suppressed, and the amount of heat transferred to the capacitor module 2 can be reduced. That is, the semiconductor device 1 according to the present embodiment is configured so that heat does not accumulate inside, and the heat inside the semiconductor device 1 can be efficiently released to the outside via the cooling device 4. ..

Further, according to the semiconductor device 1 according to the present embodiment, chamfered surfaces (317, 337) are formed at the rear end portions of the first conductive member 31 and the third conductive member 33 which are adjacently arranged via the insulating sheet 8. These chamfered surfaces are arranged so as to face each other with the insulating sheet 8 interposed therebetween. By forming such a chamfered surface, it is possible to effectively prevent a short circuit due to creeping discharge between the first conductive member 31 and the third conductive member 33 when the semiconductor device 1 is energized.

Although the embodiments of the present invention have been described above, the present invention should not be limited to the above embodiments. For example, in the above embodiment, the transistor is exemplified as the first semiconductor element and the second semiconductor element, but other semiconductor elements such as diodes can also be used. Further, in the above embodiment, an example in which a pair of first transistors 36, 36 are used as the first semiconductor element and a pair of second transistors 37, 37 are used as the second semiconductor element has been described. The two semiconductor elements may be singular or plural, respectively. Further, flexible wiring having flexibility in the signal lines connected to the first transistor 36 and the second transistor 37 (for example, the signal line connected to the gate electrode and the signal line connected to the source electrode) used in the above embodiment. Can also be used. According to this, these signal lines can be directly connected to the control board by falling into the flexible wiring. Therefore, it is possible to omit the intermediate terminal for connecting these wirings to the control board, and it is possible to reduce the cost. Further, in the above embodiment, copper is exemplified as the material of each conductive member and the conductive connecting member, but any material having electrical conductivity and thermal conductivity, preferably a material having excellent electrical conductivity and thermal conductivity. , A material other than copper may be used. As described above, the present invention can be modified as long as it does not deviate from the gist thereof.

1 ... Semiconductor device, 2 ... Condenser module, 3 ... Power module, 3A ... First power module, 3B ... Second power module, 3C ... Third power module, 31 ... First conductive member, 311 ... Front, 312 ... Rear , 313 ... Right surface, 313a ... Right front surface (first semiconductor joint surface), 313b ... Right rear surface (contact surface), 314 ... Left surface, 315 ... Upper surface (first mounting surface), 316 ... Lower surface (first heat radiation surface) , 317 ... chamfered surface, 32 ... second conductive member, 321 ... main body, 322 ... heat radiating part, 322a ... lower surface (second heat radiating surface), 322b ... upper surface (mounting surface), 323 ... first joint, 33 ... Third conductive member, 331 ... Front surface, 332 ... Rear surface, 333 ... Right surface (second semiconductor joint surface), 334 ... Left surface (opposing surface), 335 ... Upper surface, 336 ... Lower surface (third heat radiation surface), 337 ... Chamfering Surface, 34 ... Fourth conductive member, 341 ... Main body, 342 ... Heat dissipation part, 342a ... Lower surface (fourth heat dissipation surface), 342b ... Upper surface (second mounting surface), 343 ... Second joint, 35 ... Conductive Connecting member, 351 ... Main body, 351a ... Bottom surface, 352 ... Connection piece, 36 ... First transistor (first semiconductor element), 37 ... Second transistor (second semiconductor element), 4 ... Cooling device, 41 ... Top surface (Cooling surface), 5 ... Current sensor, 8 ... Insulation sheet (sheet-like insulation member), 9 ... Insulation sheet, 223, 225, 227 ... First connection terminal, 224, 226, 228 ... Second connection terminal, D ... Drain electrode (first electrode), S ... Source electrode (second electrode), G ... Gate electrode, M ... Three-phase DC brushless motor, V ... Power supply

Claims (5)

A first semiconductor device and a second semiconductor device having one main surface on which the first electrode is formed and the other main surface on the side opposite to the one main surface on which the second electrode is formed. When,
A first semiconductor bonding surface formed of a metal having electrical conductivity and thermal conductivity, to which one of the main surfaces of the first semiconductor element is bonded, and a contact surface facing the same direction as the first semiconductor bonding surface. And a first conductive member having a first heat radiation surface facing in a direction different from that of the first semiconductor joint surface.
With a first joint portion formed of a metal having electrical conductivity and thermal conductivity and joined to the other main surface of the first semiconductor element joined to the first semiconductor joint surface of the first conductive member. , A second conductive member having a second heat radiating surface facing the same direction as the first heat radiating surface,
A second semiconductor junction surface formed of a metal having electrical conductivity and thermal conductivity, facing the same direction as the first semiconductor junction surface and to which one of the main surfaces of the second semiconductor element is bonded, and the first semiconductor junction surface. (Ii) A surface facing in the opposite direction to the semiconductor bonding surface and facing the contact surface via a sheet-shaped insulating member, and a third heat radiating surface facing the same direction as the first heat radiating surface. And a third conductive member arranged adjacent to the first conductive member via the insulating member.
With a second junction formed of a metal having electrical conductivity and thermal conductivity and bonded to the other main surface of the second semiconductor element bonded to the second semiconductor bonding surface of the second conductive member. A fourth conductive member having a fourth heat radiating surface facing in the same direction as the first heat radiating surface,
A cooling device having a cooling surface having surface contact with the first heat radiation surface, the second heat radiation surface, the third heat radiation surface, and the fourth heat radiation surface.
A semiconductor device. In the semiconductor device according to claim 1,
A conductive connecting member formed of a metal having electrical conductivity and thermal conductivity and electrically connected to the second conductive member and the third conductive member.
The first conductive member is electrically connected to either the positive electrode or the negative electrode of the power supply.
The fourth conductive member is electrically connected to either the positive electrode or the negative electrode of the power supply.
The conductive connecting member is a semiconductor device that is electrically connected to a power load. In the semiconductor device according to claim 2,
The second conductive member has a heat radiating portion having a second heat radiating surface and a mounting surface facing the direction opposite to the second heat radiating surface.
The conductive connecting member includes a main body portion connected to the heat radiating portion while being mounted on the above-mentioned mounting surface, and a connecting piece portion extending from the main body portion and connected to the third conductive member. A semiconductor device. In the semiconductor device according to claim 2 or 3.
The first semiconductor joint surface and the contact surface of the first conductive member are formed in the order of the contact surface and the first semiconductor joint surface from the rear to the front in a predetermined first direction.
The position where the conductive connecting member is connected to the third conductive member is higher than the position where the one main surface of the second semiconductor element is joined to the second semiconductor bonding surface of the third conductive member. A semiconductor device that is forward in the first direction. In the semiconductor device according to any one of claims 1 to 4.
Further provided with a third semiconductor element connected to a power source and having a first connection terminal and a second connection terminal,
The first conductive member has a first mounting surface on which the first connection terminal is mounted.
The fourth conductive member has a second mounting surface on which the second connection terminal is mounted.
The first connection terminal is welded to the first mounting surface,
A semiconductor device in which the second connection terminal is welded to the second mounting surface.

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