阅读说明：本技术 半导体装置及半导体装置的制造方法 (Semiconductor device and method for manufacturing semiconductor device ) 是由 洼内源宜 于 2020-09-30 设计创作，主要内容包括：提供半导体装置及半导体装置的制造方法。正面的正上方不受空间限制。半导体装置具有具备外部连接端子(24)的半导体模块和导通基板(40),该导通基板(40)具备贯通主面而形成的端子孔(41),外部连接端子(24)的另一端部从端子孔(41)的入口(41a)向出口(41b)嵌合到端子孔(41)而被焊料(50)固定,导通基板(40)与外部连接端子(24)电连接。此外,在端子孔(41)形成有卡止另一端部针对端子孔(41)的插通的作为阶梯差(42)的卡止部。外部连接端子(24)的另一端部针对端子孔的插通被卡止部卡合而使外部连接端子(24)的另一端部留在端子孔。因此,以不从导通基板突出的方式接合到导通基板。(A semiconductor device and a method for manufacturing the semiconductor device are provided. The space directly above the front face is not limited. The semiconductor device includes a semiconductor module having an external connection terminal (24), and a conductive substrate (40), the conductive substrate (40) having a terminal hole (41) formed through a main surface, the other end of the external connection terminal (24) being fitted into the terminal hole (41) from an inlet (41a) to an outlet (41b) of the terminal hole (41) and fixed by solder (50), and the conductive substrate (40) being electrically connected to the external connection terminal (24). Furthermore, a locking part as a step (42) for locking the other end part to insert into the terminal hole (41) is formed in the terminal hole (41). The other end of the external connection terminal (24) is engaged with the insertion-receiving portion of the terminal hole, and the other end of the external connection terminal (24) is left in the terminal hole. Therefore, the bonding is performed so as not to protrude from the conductive substrate.)

1. A semiconductor device is characterized by comprising a semiconductor module and a first conductive substrate,

the semiconductor module has a semiconductor element and a first external connection terminal, a first end portion of the first external connection terminal is electrically connected to the semiconductor element, a first other end portion of the first external connection terminal extends from the semiconductor element,

the first conductive substrate includes a first terminal hole formed to penetrate a main surface, the first other end portion is fitted into the first terminal hole from a first inlet to a first outlet of the first terminal hole and fixed by solder, the first conductive substrate is electrically connected to the first external connection terminal,

a first locking portion is formed as a step, a tapered portion, or a projection in at least one of the first terminal hole and the first other end portion, and the first other end portion is locked by the first locking portion with respect to insertion of the first terminal hole so as to leave the first other end portion in the first terminal hole.

2. The semiconductor device according to claim 1, wherein the semiconductor module has a sealing portion which seals the semiconductor element and the first end portion of the first external connection terminal, the first other end portion of the first external connection terminal extends from the sealing portion,

the first conductive substrate is disposed at the first end portion outside the sealing portion.

3. The semiconductor device according to claim 1, wherein the semiconductor module has a package portion which packages the semiconductor element, the first external connection terminal, and the first via substrate.

4. The semiconductor device according to any one of claims 1 to 3, wherein when the first locking portion is the step, the first locking portion is formed on at least one of an inner periphery of the first terminal hole and a side peripheral surface of the first other end portion.

5. The semiconductor device according to claim 4, wherein the step is formed in a peripheral portion of the first front end surface of the first other end portion,

a first protrusion is provided at a center portion of the first distal end surface.

6. The semiconductor device according to claim 5, wherein the step is formed in a peripheral portion of the first front end surface of the first other end portion,

the first terminal hole is hollow and columnar, the first protrusion is fitted into the first entrance of the first terminal hole, and the first locking portion is locked to a peripheral portion of the first entrance of the first terminal hole.

7. The semiconductor device according to claim 4, wherein the step difference includes a first step difference formed in a peripheral portion of a first front end surface of the first other end portion and a second step difference formed midway from the first inlet to the first outlet of the first terminal hole,

the first distal end surface is fitted between the second step of the first terminal hole and the first outlet, and the first step of the first other end portion is locked to the second step of the first terminal hole.

8. The semiconductor device according to claim 5, wherein the first protruding portion is a spacer.

9. The semiconductor device according to claim 5, wherein the first protruding portion is formed integrally with the first front end face.

10. The semiconductor device according to any one of claims 1 to 3, wherein when the first locking portion is the protrusion, the first locking portion is formed along at least a part of an inner circumference of the first terminal hole or an outer circumference of a side circumferential surface of the first other end portion.

11. The semiconductor device according to claim 5, wherein the protrusion is formed on at least a part of a side peripheral surface of the first other end portion along a peripheral diameter of the side peripheral surface,

the first end surface is positioned between the first inlet and the first outlet of the first terminal hole, the first other end portion is fitted into the first terminal hole, and the first locking portion is locked to a peripheral portion of the first inlet of the first terminal hole.

12. The semiconductor device according to any one of claims 1 to 3, wherein when the first locking portion is a tapered portion, the first locking portion is formed on at least one of an inner peripheral surface of the first terminal hole and a side peripheral surface of the first other end portion.

13. The semiconductor device according to claim 12, wherein the tapered portion is formed on a side peripheral surface of the first other end portion and an inner peripheral surface of the first terminal hole,

a distal end surface of the first other end portion is fitted between the first inlet and the first outlet, and the side peripheral surface of the first other end portion is locked to the inner peripheral surface of the first terminal hole.

14. The semiconductor device according to claim 3, wherein the semiconductor module has a second external connection terminal, a second end portion of the second external connection terminal is electrically connected to the semiconductor element in the package portion together with the first external connection terminal, a second other end portion of the second external connection terminal extends from the package portion,

the semiconductor device includes a second conductive substrate provided on the semiconductor module side with respect to the first conductive substrate, the second conductive substrate including a lower opening through which the first external connection terminal is inserted and a second terminal hole formed to penetrate a main surface, the second other end portion of the second external connection terminal being fitted from a second inlet to a second outlet of the second terminal hole and fixed by solder, and the second conductive substrate being electrically connected to the second external connection terminal,

the first conductive substrate has an upper opening formed at a position facing the second distal end surface of the second end of the second external connection terminal.

15. The semiconductor device according to claim 14, wherein a second locking portion which is a step, a tapered portion, or a protrusion for locking the second other end portion with respect to insertion of the second terminal hole is formed in at least one of the second terminal hole and the second other end portion of the second conductive substrate, and insertion of the second other end portion with respect to the second terminal hole is locked by the second locking portion so that the second other end portion remains in the second terminal hole.

16. The semiconductor device according to claim 15, wherein a first front end surface of the first external connection terminal is located above a second front end surface of the second external connection terminal.

17. The semiconductor device according to claim 15, wherein the semiconductor device comprises at least one of the first concave portion and the second concave portion,

the first recess is formed by recessing the first terminal hole toward the lower opening side on the first conductive substrate,

the second concave portion is formed by recessing the second terminal hole toward the upper opening side on the second conductive substrate.

18. The semiconductor device according to claim 14, wherein a first front end surface of the first external connection terminal and the second front end surface of the second external connection terminal are located at the same position, and the second external connection terminal penetrates the first conductive substrate through the second terminal hole.

19. The semiconductor device according to any one of claims 1 to 3, wherein when the first locking portion is the protrusion,

the area of the first front end surface of the first other end portion is larger than the area of the first inlet,

the protrusion is formed on a peripheral portion of the first distal end surface, the first distal end surface covers the first inlet, and the protrusion is fitted into the peripheral portion of the first inlet so that the first other end portion is engaged with the first terminal hole.

20. A method for manufacturing a semiconductor device, comprising the steps of:

preparing a semiconductor module having a semiconductor element, a sealing portion for sealing the semiconductor element, and a first external connection terminal having a first end electrically connected to the semiconductor element in the sealing portion and a first other end extending from the sealing portion, and a first conductive substrate having a first terminal hole formed so as to penetrate a main surface;

disposing solder on at least one of a first outlet of the first terminal hole and a peripheral portion of the first outlet of the first conductive substrate;

fitting the first other end portion of the first external connection terminal into the first terminal hole of the first conductive substrate from a first inlet to the first outlet; and

a step of melting the solder, and fixing the first other end portion of the first external connection terminal to the first terminal hole with the melted solder,

a first locking portion is formed as a step, a tapered portion, or a projection in at least one of the first terminal hole and the first other end portion, and the first other end portion is locked by the first locking portion with respect to insertion of the first terminal hole so as to leave the first other end portion in the first terminal hole.

Technical Field

The present invention relates to a semiconductor device and a method for manufacturing the semiconductor device.

Background

The Semiconductor module includes Semiconductor chips such as an IGBT (Insulated Gate Bipolar Transistor), a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), and the like, and is provided with a plurality of pin-shaped external connection terminals extending vertically from the front surface thereof. The external connection terminal is electrically connected to the control electrode and the main electrode of the semiconductor chip inside the semiconductor module. The semiconductor device includes a plurality of such semiconductor modules, and further includes a printed circuit board or a bus bar mounted on an external connection terminal of each semiconductor module. Thus, the semiconductor device functions as, for example, a power converter.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2011-142124

Patent document 2: japanese patent laid-open publication No. 2017-163016

Disclosure of Invention

Technical problem

In the above semiconductor device, the external connection terminals protrude from the printed circuit board. That is, a space for allowing the external connection terminals to protrude is required right above the front surface of the semiconductor device. Therefore, it is not possible to dispose an insulating sheet or the like directly above the front surface of the semiconductor device. In addition, when another device is disposed directly above the front surface of the semiconductor device, a space for a portion where the external connection terminal protrudes needs to be made available. Further, since the semiconductor device requires such a space, the degree of freedom in mounting the semiconductor device may be limited by the mounting position of the semiconductor device.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a semiconductor device and a method for manufacturing the semiconductor device, in which space immediately above the front surface is not limited.

Technical scheme

According to an aspect of the present invention, there is provided a semiconductor device including a semiconductor module having a semiconductor element and a first external connection terminal, a first end of the first external connection terminal being electrically connected to the semiconductor element, a first other end of the first external connection terminal extending from the semiconductor element, the first conductive substrate including a first terminal hole formed to penetrate a main surface, the first other end being fitted into the first terminal hole from a first inlet to a first outlet of the first terminal hole and fixed by solder, and a first conductive substrate electrically connected to the first external connection terminal, a first locking portion being a step, a tapered portion, or a protrusion being formed in at least one of the first terminal hole and the first other end, and the first other end being locked to the first locking portion by the first locking portion being inserted into the first terminal hole One end part is left in the first terminal hole.

In addition, according to an aspect of the present invention, there is provided a method for manufacturing the semiconductor device.

Effects of the invention

According to the disclosed technology, the space directly above the front surface is not limited, and the space directly above the front surface can be effectively used, or the size can be reduced.

Drawings

Fig. 1 is a perspective view (one of) showing an external appearance of a semiconductor module.

Fig. 2 is a perspective view (two) showing an external appearance of the semiconductor module.

Fig. 3 is a sectional view of the semiconductor module.

Fig. 4 is a diagram for explaining an example of the semiconductor device according to the first embodiment.

Fig. 5 is (one of) a diagram for explaining bonding of external connection terminals to a conductive substrate according to the first embodiment.

Fig. 6 is a diagram (two) for explaining the bonding of the external connection terminal to the conductive substrate according to the first embodiment.

Fig. 7 is a (third) view for explaining the bonding of the external connection terminal to the conductive substrate according to the first embodiment.

Fig. 8 is a diagram (fourth) for explaining the bonding of the external connection terminal to the conductive substrate according to the first embodiment.

Fig. 9 is a diagram (five) for explaining the bonding of the external connection terminal to the conductive substrate according to the first embodiment.

Fig. 10 is a diagram (sixth) for explaining the bonding of the external connection terminal to the conductive substrate according to the first embodiment.

Fig. 11 is a diagram (seventeenth) for explaining the bonding of the external connection terminal to the conductive substrate according to the first embodiment.

Fig. 12 is (one of) a diagram for explaining a method of bonding external connection terminals to a conductive substrate according to the first embodiment.

Fig. 13 is a diagram (two) for explaining a method of bonding external connection terminals to a conductive substrate according to the first embodiment.

Fig. 14 is a (third) view for explaining a method of bonding an external connection terminal to a conductive substrate according to the first embodiment.

Fig. 15 is (one of) a diagram showing an example of the semiconductor device according to the first embodiment.

Fig. 16 is a diagram (two) showing an example of the semiconductor device of the first embodiment.

Fig. 17 is a diagram for explaining the bonding of the external connection terminals to the printed circuit board according to the second embodiment.

Fig. 18 is a diagram (one of) for explaining a plurality of semiconductor modules mounted with bus bars according to the third embodiment.

Fig. 19 is (one of) a diagram for explaining joining of the external connection terminal to the bus bar of the third embodiment.

Fig. 20 is a diagram (two) for explaining a plurality of semiconductor modules to which bus bars are attached according to the third embodiment.

Fig. 21 is a diagram (two) for explaining joining of the external connection terminal to the bus bar according to the third embodiment.

Fig. 22 is a (third) view for explaining the joining of the external connection terminal to the bus bar in the third embodiment.

Fig. 23 is a sectional view of a semiconductor module of the fourth embodiment.

Description of the symbols

1. 1 a: semiconductor device with a plurality of semiconductor chips

10. 10 a: semiconductor module

11A: first insulating substrate

11B: second insulating substrate

12 a: first circuit board

12 b: second circuit board

13: metal plate

14: first semiconductor element

15: second semiconductor element

16: third semiconductor element

17: fourth semiconductor element

18: printed circuit board

19. 20: conductive pole

21a, 21b, 22a, 22b, 23, 24, 25: external connection terminal

21aa, 22aa, 23a, 24c, 24 f: protrusion part

21ab, 22ab, 24 b: peripheral part

21ae, 22ae, 23e, 24e, 42, 82 c: step difference

24d, 43: cone part

26: spacer member

30: packaging part

40. 40a, 40b, 40c, 40d, 61, 62, 63, 71, 72: conducting substrate

41: terminal hole

41a, 82 a: inlet port

41b, 82 b: an outlet

50. 51: solder

60: bus bar

60 a: first side

60 b: second surface

61 a: upper part opening

62 a: lower opening

64: insulating paper

70: cooling device

71 a: upper part opening

72 a: lower opening

74: insulating substrate

75. 76: capacitor with a capacitor element

80: printed circuit board

81 a: insulating layer

81b, 81 c: conductive layer

81d, 81 e: protective layer

82: through hole

83: coating film

Detailed Description

Hereinafter, embodiments will be described with reference to the drawings. In the following description, the "front surface" and the "upper surface" represent surfaces facing upward in the semiconductor module 10 of fig. 1. Similarly, "up" indicates a direction of an upper side in the semiconductor module 10 of fig. 1. The "back surface" and the "lower surface" represent surfaces facing downward in the semiconductor module 10 of fig. 1. Similarly, "lower" refers to a direction of a lower side in the semiconductor module 10 of fig. 1. The same directionality is shown in other figures as necessary. The terms "front surface", "upper", "back surface", "lower" and "side" are merely expressions for easily determining relative positional relationships, and do not limit the technical spirit of the present invention. For example, "upper" and "lower" do not necessarily refer to directions perpendicular to the ground. That is, the directions of "up" and "down" are not limited to the gravity direction.

[ first embodiment ]

An example of a semiconductor module used in the first embodiment will be described with reference to fig. 1 to 3. Fig. 1 and 2 are perspective views showing an external appearance of the semiconductor module, and fig. 3 is a sectional view of the semiconductor module. Fig. 3 is a cross-sectional view of the semiconductor module 10 of fig. 1 and 2, taken along a center line passing through the center of the semiconductor module 10 in the longitudinal direction.

The semiconductor module 10 includes: the semiconductor device includes a first semiconductor element 14 to a fourth semiconductor element 17, which will be described later, a package 30 that packages the first semiconductor element 14 to the fourth semiconductor element 17, conductive posts 19 and 20 electrically connected to the first semiconductor element 14 to the fourth semiconductor element 17 in the package 30, and external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25. That is, as shown in fig. 3, the semiconductor module 10 includes first to fourth semiconductor elements 14 to 17, a first circuit board 12a, a second circuit board 12b, and a third circuit board (not shown) therein. The semiconductor module 10 further includes a printed circuit board 18, conductive posts 19 and 20, and external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25. The semiconductor module 10 is packaged by a package portion 30 having a substantially rectangular parallelepiped shape. The external connection terminals 21a, 22a, 23, 24, and 25 and the external connection terminals 21b, 22b, 23, 24, and 25 are disposed at line-symmetrical positions on the front surface of the package portion 30, respectively, with the longitudinal center line as an axis.

One end portions of the external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 extend from the front surface of the package portion 30 into the package portion 30 of the semiconductor module 10, and the other end portions extend from the front surface of the package portion 30 perpendicularly to the front surface. Further, the other end portions were arranged in 2 rows in the longitudinal direction. The external connection terminals 21a, 21b, 22a, 22b are control terminals for controlling the switches of the semiconductor module 10. The external connection terminals 21a and 21b are gate terminals (G1 terminal and G2 terminal) electrically connected to gate electrodes of the first semiconductor element 14 and the third semiconductor element 16, which will be described later. The external connection terminals 22a and 22b are kelvin emitter terminals (E1s terminal and E2s terminal) electrically connected to emitters of the first semiconductor element 14 and the third semiconductor element 16, which will be described later. The external connection terminals 23, 24, and 25 are main terminals to which a main current is input and output. The external connection terminal 23 is an input terminal (P terminal) that is electrically connected to a collector of the first semiconductor element 14, which will be described later, and through which an input current on the positive side flows. The external connection terminal 24 is an input terminal (N terminal) that is electrically connected to an emitter of the third semiconductor element 16 described later and through which an input current flows on the negative electrode side. The external connection terminal 25 is an output terminal (O terminal) that is electrically connected to an emitter of the first semiconductor element 14 and a collector of the third semiconductor element 16, which will be described later, and through which an output current flows. The external connection terminals 23, 24, and 25 are arranged in parallel with the short side direction of the semiconductor module 10 by 2. The external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 have a cylindrical or prismatic shape. From the viewpoint of electrical connection, the shape of the external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 is preferably the same as the shape of the terminal hole 41 of the conductive substrate 40 described later. In addition, from the viewpoint of workability of mounting, the shapes of the external connection terminals 21a, 21b, 22a, 22b, 23, 24, 25 and the terminal hole 41 of the conduction substrate 40 are more preferably cylindrical. The external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 are made of a material having excellent conductivity. Such a material is made of, for example, silver, copper, nickel, or an alloy containing at least one of these.

The semiconductor module 10 includes a first insulating substrate 11A and a second insulating substrate 11B arranged side by side in a horizontal direction. The first insulating substrate 11A and the second insulating substrate 11B are made of ceramics having good thermal conductivity, such as alumina, aluminum nitride, and silicon nitride. A first circuit board 12a is disposed on the upper surface of the first insulating substrate 11A, and a metal plate 13 having the same thickness is disposed on the rear surface. Further, a second circuit board 12B is disposed on the upper surface of the second insulating substrate 11B, and a metal plate 13 having the same thickness is disposed on the rear surface. Further, a plurality of third circuit boards are arranged on the upper surfaces of the first insulating substrate 11A and the second insulating substrate 11B. The first circuit board 12a, the second circuit board 12b, and the third circuit board have a thickness of, for example, 0.5mm or more and 1.5mm or less. The first circuit board 12a and the second circuit board 12b are made of a material having excellent conductivity. Such a material is made of, for example, silver, copper, nickel, or an alloy containing at least one of these. In order to improve the corrosion resistance, the surfaces of the first circuit board 12a and the second circuit board 12b may be subjected to plating treatment or the like with a material such as nickel. The material includes nickel, nickel-phosphorus alloy, nickel-boron alloy, and the like. The metal plate 13 is made of a metal having excellent thermal conductivity, such as aluminum, iron, silver, copper, or an alloy containing at least one of these metals. As shown in fig. 2, the metal plate 13 is exposed from the back surface of the sealing portion 30. For example, a DCB (Direct Copper Bonding) substrate or an AMB (Active Metal soldered) substrate can be used as the first insulating substrate 11A and the second insulating substrate 11B.

In this way, a cooler (not shown) may be attached to the rear surface of the semiconductor module 10 where the metal plate 13 is exposed from the rear surface to improve heat dissipation. The cooler is made of, for example, aluminum, iron, silver, copper, or an alloy containing at least one of these, which has excellent thermal conductivity. Further, as the cooler, a radiator composed of a plurality of fins, a cooling device by water cooling, or the like can be used. In addition, the substrate may be integrally configured with such a cooler. In this case, the substrate is made of aluminum, iron, silver, copper, or an alloy containing at least one of these, which has excellent thermal conductivity. In order to improve corrosion resistance, a material such as nickel may be formed on the surface of the heat sink integrated with the cooler by plating or the like, for example. The material includes nickel, nickel-phosphorus alloy, nickel-boron alloy, and the like.

The first semiconductor element 14 and the second semiconductor element 15 are mounted on the first circuit board 12a via solder (not shown). The third semiconductor element 16 and the fourth semiconductor element 17 are mounted on the second circuit board 12b via solder (not shown). The first to fourth semiconductor elements 14 to 17 are mounted on the first insulating substrate 11A and the second insulating substrate 11B, respectively. This is because, in the case where the first insulating substrate 11A and the second insulating substrate 11B are integrally formed, deformation of the insulating substrates due to thermal stress becomes large, and therefore, the insulating substrates, resin cracks, or peeling of the circuit board, resin from the insulating substrates, or the like may be caused by this influence. On the other hand, in the present embodiment, by dividing the insulating substrate into 2 pieces, reliability can be improved.

The first semiconductor element 14 and the third semiconductor element 16 are switching elements, and include semiconductor elements made of silicon or silicon carbide, such as IGBTs and power MOSFETs. The first semiconductor element 14 and the third semiconductor element 16 each have, for example, a collector (or a drain electrode) as a main electrode on the back surface and a gate electrode and an emitter (or a source electrode) as main electrodes on the front surface. The second semiconductor element 15 and the fourth semiconductor element 17 are Diode elements serving as FWDs (Free Wheeling diodes), and include SBDs (Schottky Barrier diodes), PiN (P-intrinsic-N Diode) diodes, and the like. The second semiconductor element 15 and the fourth semiconductor element 17 have a cathode electrode as a main electrode on the back surface and an anode electrode as a main electrode on the front surface. When the first to fourth semiconductor elements 14 to 17 are made of silicon carbide, the thickness thereof is, for example, 180 μm or more and 220 μm or less, and the average thickness is about 200 μm. When the first to fourth semiconductor elements 14 to 17 are made of silicon, the thickness thereof is, for example, 60 μm or more and 200 μm or less, and the average thickness is about 120 μm.

The printed circuit board 18 is disposed above the first circuit board 12a and the second circuit board 12b so as to face the first circuit board 12a and the second circuit board 12b with a predetermined gap therebetween. The printed circuit board 18 has a metal layer having a wiring pattern on an upper surface thereof and a metal layer having a wiring pattern on a lower surface thereof. The metal layers are not shown in the drawings.

The predetermined metal layer of the printed circuit board 18 is electrically connected to the first circuit board 12a and the second circuit board 12b or the third circuit board through the conductive post 19. The predetermined metal layer of the printed circuit board 18 and the first to fourth semiconductor elements 14 to 17 are electrically connected by the conductive post 20. In addition, external connection terminals 21a, 21b, 22a, 22b, 23, 24, 25 are electrically and mechanically connected to the first circuit board 12a and the third circuit board. For the connection of the above-described members, a conductive bonding material such as solder or a metal sintered material can be used.

The first circuit board 12a, the second circuit board 12b, the third circuit board, the first to fourth semiconductor elements 14 to 17, the conductive posts 19 and 20, and the printed circuit board 18 are packaged by the packaging part 30. The sealing portion 30 contains a thermosetting resin such as an epoxy resin, a phenol resin, and a maleimide resin, and a filler contained in the thermosetting resin. Examples of the sealing portion 30 include an epoxy resin and a filler such as silica, alumina, boron nitride, or aluminum nitride as a filler in the epoxy resin. Then, the semiconductor module 10 shown in fig. 1 and 2 is formed.

The semiconductor module 10 is electrically connected as follows. The collector of the first semiconductor element 14 is connected to the external connection terminal 23(P terminal) via the first circuit board 12 a. The emitter of the first semiconductor element 14 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 25(O terminal) via the conductive post 19 and the second circuit board 12 b. The gate electrode of the first semiconductor element 14 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 21a (G1 terminal) via the conductive post 19 and the third circuit board. The auxiliary emitter of the first semiconductor element 14 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 22a (E1s terminal) via the conductive post 19 and the third circuit board.

The cathode electrode of the second semiconductor element 15 is connected to the external connection terminal 23(P terminal) via the first circuit board 12 a. The anode electrode of the second semiconductor element 15 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 25(O terminal) via the conductive post 19 and the second circuit board 12 b.

The collector of the third semiconductor element 16 is connected to the external connection terminal 25(O terminal) via the second circuit board 12 b. The emitter of the third semiconductor element 16 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 24(N terminal) via the conductive post 19 and the third circuit board. The gate electrode of the third semiconductor element 16 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 21b (G2 terminal) via the conductive post 19 and the third circuit board. The auxiliary emitter of the third semiconductor element 16 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 22b (E2s terminal) via the conductive post 19 and the third circuit board.

The cathode electrode of the fourth semiconductor element 17 is connected to the external connection terminal 25(O terminal) via the second circuit board 12 b. The anode electrode of the fourth semiconductor element 17 is first connected to the metal layer of the printed circuit board 18 via the conductive post 20, and then connected to the external connection terminal 24(N terminal) via the conductive post 19 and the third circuit board.

Next, a semiconductor device including a plurality of semiconductor modules 10 including the plurality of external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 will be described with reference to fig. 4. Fig. 4 is a diagram for explaining an example of the semiconductor device according to the first embodiment. Fig. 4 (a) is a plan view of the semiconductor device 1, and fig. 4 (B) is a cross-sectional view of the semiconductor device 1 at the one-dot chain line Y-Y of fig. 4 (a). Here, the bonding of the external connection terminals 21a, 23, 24, and 25 to the conductive substrates 40a to 40d is simplified. The semiconductor device 1 includes 3 semiconductor modules 10 constituting a 3-phase bridge inverter circuit and conductive substrates 40a to 40 d. When the conductive substrates 40a to 40d are not distinguished, the conductive substrate 40 may be described as a conductive substrate.

The conductive substrate 40 is a plate including a conductor. Such as bus bars, printed circuit boards, etc. The conductive substrate 40 can electrically connect external devices such as a drive circuit, a power supply, and an output device to the external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 of the semiconductor module 10, and control the semiconductor module 10 and input and output voltages to and from the semiconductor module 10. The conductive substrate 40 is electrically connected to the external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 of the semiconductor module 10 arranged in 2 rows. Specifically, the conductive substrate 40a is a printed circuit board. External connection terminals 21a, 21b, 22a, and 22b as control terminals are electrically connected to the conductive substrate 40 a. The conductive substrate 40b is a bus bar. To the conductive substrate 40b, an external connection terminal 23 as a main terminal is electrically connected. The conductive substrate 40c is a bus bar. To the conductive substrate 40c, an external connection terminal 24 as a main terminal is electrically connected. The conductive substrate 40d is a bus bar. To the conductive substrate 40d, an external connection terminal 25 as a main terminal is electrically connected. At this time, the other end portions of the external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 are electrically connected to the via substrate 40 without penetrating through the via substrate 40. The semiconductor device 1 is not limited to the case where 3 semiconductor modules 10 are included. The semiconductor device 1 may include at least 1 semiconductor module 10 and a plurality of conductive substrates 40. For example, a plurality of semiconductor modules 10 may be arranged such that long sides thereof face each other in parallel with the short side direction.

Next, the bonding of the external connection terminals 21a, 21b, 22a, 22b, 23, 24, and 25 to the conductive substrate 40 will be described with reference to fig. 5 to 11. Fig. 5 to 11 are views for explaining the bonding of the external connection terminal to the conductive substrate according to the first embodiment. Fig. 5 to 10 are cross-sectional views taken along a one-dot chain line X-X in fig. 4 (a). Fig. 5A, 5B, fig. 6 a, 6B, 7 a, 7B, fig. 8 to 10, 11a, and 11B show examples of bonding external connection terminals to the conductive substrate 40, respectively. In addition, the following description will be made by taking the external connection terminal 24 out of the external connection terminals. Other external connection terminals can be bonded to the conductive substrate 40 in the same manner. In the present embodiment, the conductive substrate 40 is described as a bus bar. Further, a locking portion, which is a step, a tapered portion, or a projection, is formed on at least one of the terminal hole of the conductive substrate 40 and the other end portion of the external connection terminal 24, and the other end portion of the external connection terminal 24 is locked to the locked portion for insertion of the terminal hole and remains inside the terminal hole without penetrating the conductive substrate 40. These will be specifically described below.

First, as shown in fig. 5A, a terminal hole 41 is formed in the conductive substrate 40. The terminal hole 41 is formed so as to pass through an inlet 41a on the rear surface of the conductive substrate 40 and an outlet 41b on the front surface on the opposite side of the rear surface. The shape of the terminal hole 41 in plan view is circular, square, or the like in accordance with the shape of the external connection terminal 24. In addition, a step 42 is formed from the inlet 41a to the outlet 41 b. This step 42 is formed so as to surround the inner circumference of terminal hole 41. Therefore, at this time, the area of the inlet 41a is larger than that of the outlet 41 b. Note that step 42 may be formed partially along the inner circumference of terminal hole 41. The other end of the external connection terminal 24 is joined to the terminal hole 41. The other end of the external connection terminal 24 is cylindrical with no projection or step formed on the side peripheral surface. At this time, the peripheral portion of the distal end surface of the other end portion of the external connection terminal 24 abuts on the step 42 of the terminal hole 41, and is fixed by the solder 50 in the gap between the external connection terminal 24 and the terminal hole 41. The other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40.

As shown in fig. 5B, in the conductive substrate 40, the terminal hole 41 is formed to penetrate from the inlet 41a on the rear surface to the outlet 41B on the front surface on the opposite side of the rear surface. The shape of the terminal hole 41 in plan view is circular, square, or the like in accordance with the shape of the external connection terminal 24. Further, a projection 24c as an engaging portion is formed to project into the terminal hole 41 at a predetermined position from an entrance 41a of the inner peripheral surface of the terminal hole 41. The protrusion 24c is formed between the recess and the recess. Step 42 formed on the inner peripheral surface of terminal hole 41 by protrusion 24c is formed so as to surround the inner periphery of terminal hole 41. Alternatively, it may be formed on at least a part of the inner peripheral surface. The other end of the external connection terminal 24 is joined to the terminal hole 41. The other end of the external connection terminal 24 has a columnar shape with no projection or step formed on the side peripheral surface. At this time, the peripheral portion of the distal end surface of the other end portion of the external connection terminal 24 abuts on the projection portion 24c, and is fixed by the solder 50 in the gap between the external connection terminal 24 and the terminal hole 41. The other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40.

As shown in fig. 6 (a), in the conductive substrate 40, the terminal hole 41 is formed to penetrate from the inlet 41a on the rear surface to the outlet 41b on the front surface on the opposite side of the rear surface. At this time, the terminal hole 41 is hollow in a columnar shape without forming a protrusion or a step on the inner peripheral surface. The inlet 41a and the outlet 41b of the terminal hole 41 face each other, and have the same shape and the same area. On the other hand, the protrusion 24a is formed on the distal end surface of the external connection terminal 24, and the step 24e is formed on the peripheral portion 24b surrounding the protrusion 24 a. The protrusion 24a of the external connection terminal 24 is fitted to the terminal hole 41 via the solder 50, and the step 24e formed in the peripheral portion 24b of the external connection terminal 24 abuts against the edge of the inlet 41a of the terminal hole 41 of the conductive substrate 40. In this way, the external connection terminals 24 are joined to the terminal holes 41 of the conductive substrate 40. The other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40. Further, by forming the protrusion 24a on the front end surface of the external connection terminal 24, the area of adhesion between the external connection terminal 24 and the solder 50 is increased by the solder 50, and therefore the external connection terminal 24 is more firmly joined to the terminal hole 41 than in the case of fig. 5A.

As shown in fig. 6 (B), the terminal hole 41 of the conductive substrate 40 is a columnar hollow having no projection or step formed on the inner peripheral surface. The external connection terminal 24 has a protrusion 24c formed along a side peripheral surface thereof at a predetermined distance from the distal end surface of the other end portion. The protrusion 24c may be formed so as to surround the side circumferential surface of the external connection terminal 24, or may be formed at least partially along the circumferential diameter of the side circumferential surface. The protrusion 24c of the external connection terminal 24 is pressed by a pressing tool to form the upper and lower portions (with respect to the longitudinal direction of the external connection terminal 24) of a predetermined region to form a concave portion. Thus, the position sandwiched by the concave portion is raised to form a convex portion, and the protrusion portion 24c is provided between the concave portion and the concave portion. In this way, the protrusion 24c may be provided in advance on the side peripheral surface of the external connection terminal 24, or the protrusion 24c may be provided separately. If such an external connection terminal 24 is inserted into the terminal hole 41 of the conductive substrate 40 from the inlet 41a, the protrusion 24c abuts on the edge of the inlet 41a of the terminal hole 41. Thereby, the external connection terminals 24 are fixed by the solder 50 in the gap between the external connection terminals and the terminal holes 41. The other end portion has a front end surface located between the inlet 41a and the outlet 41b of the terminal hole 41. Therefore, the external connection terminal 24 is electrically connected to the via substrate 40 without penetrating the via substrate 40.

As shown in fig. 7 (a), in the case of fig. 5A, a protrusion 24a is further integrally formed inside a peripheral portion 24b of the distal end surface of the external connection terminal 24. The protrusion 24a has a size and a shape in which it can be accommodated from the step 42 of the terminal hole 41 to the outlet 41 b. The protrusion 24a of the external connection terminal 24 is received in the terminal hole 41 in a region of the outlet 41b from the step 42 of the terminal hole 41. The step 24e of the peripheral portion 24b of the external connection terminal 24 abuts on the step 42 of the terminal hole 41, and is fixed by the solder 50 in the gap between the external connection terminal 24 and the terminal hole 41. The other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40. By forming the protrusion 24a on the distal end surface of the external connection terminal 24, the area of adhesion between the solder 50 and the other end portion of the external connection terminal 24 is increased by the solder 50. Therefore, the external connection terminals 24 are more firmly connected with the terminal holes 41 than in the case of fig. 5A.

As shown in fig. 7 (B), in the case of fig. 5A, a spacer 26 is further disposed on the distal end surface of the external connection terminal 24. The spacer 26 is made of the same material as the external connection terminal 24. The spacer 26 has a size and a shape that can be accommodated in the outlet 41b from the step 42 of the terminal hole 41, and has a cylindrical or prismatic shape similar to the external connection terminal 24. Therefore, the external connection terminals 24 and the spacers 26 can be electrically joined to the conductive substrate 40 without penetrating the conductive substrate 40. By disposing the spacers 26 on the front end surfaces of the external connection terminals 24, the other end portions of the external connection terminals 24 are fixed together with the spacers 26 by the solder 50, and therefore the external connection terminals 24 are more firmly joined to the terminal holes 41 than in the case of fig. 5A.

Next, as shown in fig. 8, the conductive substrate 40 has a tapered portion 43 formed on the inner peripheral surface of the terminal hole 41. When the other end portion of the external connection terminal 24 is fitted into the terminal hole 41, an outer edge portion of the distal end surface of the other end portion abuts on the tapered portion 43. Thereby, the external connection terminals 24 are fixed by the terminal holes 41 and the solder 50. The other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40.

As shown in fig. 9, in the conductive substrate 40, the terminal hole 41 is formed to penetrate from the inlet 41a on the rear surface to the outlet 41b on the front surface on the opposite side of the rear surface. On the other hand, a tapered portion 24d is formed at the other end of the external connection terminal 24. When such an external connection terminal 24 is inserted into the terminal hole 41 of the conductive substrate 40 from the inlet 41a, the tapered portion 24d abuts on the edge of the inlet 41a of the terminal hole 41. Thereby, the external connection terminals 24 are fixed by the solder 50 in the gap between the external connection terminals and the terminal holes 41. The other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40.

Next, as shown in fig. 10, the external connection terminal 24 has a tapered portion 24d formed at the other end portion. An inclined surface corresponding to the tapered portion 24d is also formed on the inner peripheral surface of the terminal hole 41 of the conductive substrate 40. When the external connection terminal 24 is inserted into the terminal hole 41 of the conductive substrate 40 from the inlet 41a, the tapered portion 24d abuts against the inclined surface of the terminal hole 41. Thereby, the external connection terminals 24 are fixed by the solder 50 in the gap between the external connection terminals and the terminal holes 41. The other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40. In this way, by forming the tapered portion 24d in the external connection terminal 24 and forming the inclined surface in the terminal hole 41, the external connection terminal 24 is more firmly joined to the terminal hole 41 than in the case of fig. 8 and 9.

Next, the external connection terminals 24 are columnar without forming projections or steps on the side peripheral surfaces. As shown in fig. 11 (a), the area of the distal end surface is larger than the area of the inlet 41 a. The external connection terminal 24 has a protrusion 24f formed on the periphery of the distal end surface of the other end portion. The protrusion 24f may be formed along the peripheral portion of the distal end surface, or may be formed in a part of the peripheral portion. In the conductive substrate 40, the terminal hole 41 is formed to penetrate from the inlet 41a on the back surface to the outlet 41b on the front surface on the opposite side of the back surface. At this time, the terminal hole 41 is hollow in a columnar shape without forming a protrusion or a step on the inner peripheral surface. The inlet 41a and the outlet 41b of the terminal hole 41 face each other, and have the same shape and the same area. The conductive substrate 40 has a recess formed in an edge portion of the inlet 41 a. The concave portion may be formed to face the protruding portion 24f of the external connection terminal 24. The recess may be formed along an edge portion of the protrusion portion 24f, or may be formed at a part of the peripheral portion. At this time, since the area of the distal end surface of the other end portion of the external connection terminal 24 is larger than the area of the inlet 41a, the peripheral portion of the distal end surface of the other end portion of the external connection terminal 24 covers the inlet 41a and abuts against the edge portion of the inlet 41a of the terminal hole 41 of the conductive substrate 40. The tip end surface of the other end portion is fixed by solder 50 that is conducted through terminal hole 41 of substrate 40. Therefore, the external connection terminal 24 can be electrically connected to the conductive substrate 40 without penetrating the conductive substrate 40. The protrusion 24f is fitted into a recess in the edge of the inlet 41a, and the other end is engaged with the terminal hole 41. Therefore, the external connection terminals 24 can be joined without being displaced from the predetermined positions of the conductive substrate 40. The protrusion 24f may be formed on the periphery of the inlet 41a of the terminal hole 41 of the conductive substrate 40. At this time, the external connection terminal 24 has a recess formed in the periphery of the distal end surface of the other end portion.

As shown in fig. 11 (B), in the case of fig. 11 (a), the spacer 26 is further disposed on the distal end surface of the external connection terminal 24, as in fig. 7 (B). The spacer 26 is made of the same material as the external connection terminal 24. The spacer 26 has a size and a shape that can be accommodated in the region of the outlet 41b from the step 42 of the terminal hole 41, and has a cylindrical or prismatic shape similar to the external connection terminal 24. Therefore, the external connection terminals 24 and the spacers 26 can be electrically joined to the conductive substrate 40 without penetrating the conductive substrate 40. By disposing the spacers 26 on the front end surfaces of the external connection terminals 24, the other end portions of the external connection terminals 24 are fixed together with the spacers 26 by the solder 50, and therefore the external connection terminals 24 are joined to the terminal holes 41 more firmly than in the case of fig. 11 (a).

As described above, the semiconductor device 1 includes the semiconductor module including the first to fourth semiconductor elements 14 to 17 and the external connection terminals 24 having one end electrically connected to the first to fourth semiconductor elements 14 to 17 and the other end extending from the first to fourth semiconductor elements 14 to 17. The circuit board 40 further includes a terminal hole 41 formed to penetrate the main surface, and the other end portion of the external connection terminal 24 is fitted into the terminal hole 41 from the inlet 41a to the outlet 41b of the terminal hole 41, fixed by the solder 50, and electrically connected to the external connection terminal 24. Further, at least one of the terminal hole 41 and the other end portion is formed with a locking portion as a step, a tapered portion, or a projection for locking the other end portion to be inserted into the terminal hole 41. The other end of the external connection terminal 24 is engaged with the engaged portion for insertion of the terminal hole 41, and the other end of the external connection terminal 24 remains in the terminal hole 41. Therefore, the bonding to the via substrate 40 can be performed without protruding from the via substrate 40. Therefore, the restriction of the space on the via substrate 40 is suppressed. Thus, the semiconductor device 1 can be made thin and small.

Next, a method of joining the external connection terminals 24 to the terminal holes 41 of the conductive substrate 40 will be described with reference to fig. 12 to 14. Fig. 12 to 14 are diagrams for explaining a method of bonding external connection terminals to conductive substrates according to the first embodiment. In the following, a bonding method related to the case of fig. 5A in fig. 5 to 11 will be described. However, bonding can be performed in the same manner as below in the case other than fig. 5A.

First, the semiconductor module 10 and the via substrate 40 are prepared. A terminal hole 41 is formed in a rear surface (main surface) of the conductive substrate 40 facing the semiconductor module 10, the terminal hole penetrating from an inlet 41a in the rear surface to an outlet 41b in the front surface on the opposite side of the rear surface. In addition, the terminal hole 41 is formed with a step 42 from the inlet 41a to the outlet 41 b.

Next, the conductive substrate 40 is provided so that the terminal hole 41 faces the external connection terminal 24, and as shown in fig. 12 (a), the solder 51 is disposed around the outlet 41b of the terminal hole 41 of the conductive substrate 40. In this case, the solder 51 may be disposed on the conducting substrate 40, and the conducting substrate 40 may be disposed on the external connection terminal 24. Then, the other end portion of the external connection terminal 24 is inserted through the inlet 41a until the other end portion abuts against the step 42 of the terminal hole 41 of the via substrate 40. At this time, the external connection terminal 24 is fitted into the terminal hole 41 of the conductive substrate 40 without penetrating the conductive substrate 40.

In this state, the solder 51 is heated and melted by, for example, an electric soldering iron. As shown in fig. 12 (B), the melted solder 51 flows into the terminal hole 41 in which the external connection terminal 24 is fitted from the outlet 41B of the conductive substrate 40, and enters the gap between the external connection terminal 24 and the terminal hole 41. The solder 50 obtained by solidifying the solder 51 that has thus entered the gap between the external connection terminal 24 and the terminal hole 41 joins the external connection terminal 24 to the terminal hole 41 as shown in fig. 5A.

Next, a bonding method different from that of fig. 12 will be described with reference to fig. 13. After the semiconductor module 10 and the conductive substrate 40 are prepared as described above, the conductive substrate 40 is provided so that the terminal hole 41 faces the external connection terminal 24, and as shown in fig. 13 (a), the solder 51 is disposed so as to close the outlet 41b of the terminal hole 41 of the conductive substrate 40. The solder 51 may be disposed at the outlet 41b of the terminal hole 41 of the conducting substrate 40, and the conducting substrate 40 may be provided on the external connection terminal 24. Then, the other end portion of the external connection terminal 24 is inserted through the inlet 41a until the other end portion abuts against the step 42 of the terminal hole 41 of the via substrate 40. At this time, the external connection terminal 24 is fitted to the conductive substrate 40 without penetrating the conductive substrate 40.

In this state, the solder 51 is heated and melted by, for example, an electric soldering iron. As shown in fig. 13 (B), the melted solder 51 flows into the terminal hole 41 in which the external connection terminal 24 is fitted from the outlet 41B of the conductive substrate 40, and enters the gap between the external connection terminal 24 and the terminal hole 41. The solder 50 obtained by solidifying the solder 51 that has thus entered the gap between the external connection terminal 24 and the terminal hole 41 joins the external connection terminal 24 to the terminal hole 41 as shown in fig. 5A.

Next, a bonding method different from the bonding method of fig. 13 will be described with reference to fig. 14. After the semiconductor module 10 and the conductive substrate 40 are prepared as described above, the conductive substrate 40 is provided so that the terminal hole 41 faces the external connection terminal 24, and as shown in fig. 14 (a), the solder 51 is disposed on the outlet 41b of the terminal hole 41 of the conductive substrate 40 so as to close the outlet 41 b. In this case, the solder 51 may be disposed first, and then the conductive substrate 40 may be provided on the external connection terminal 24. Then, the other end portion of the external connection terminal 24 is inserted through the inlet 41a until the other end portion abuts against the step 42 of the terminal hole 41 of the via substrate 40. At this time, the external connection terminal 24 is fitted to the conductive substrate 40 without penetrating the conductive substrate 40.

In this state, the solder 51 is heated and melted by, for example, an electric soldering iron. The solder 51 thus melted flows into the terminal hole 41 into which the external connection terminal 24 is fitted from the outlet 41B of the conductive substrate 40, and enters the gap between the external connection terminal 24 and the terminal hole 41, as shown in fig. 14 (B). In the case of fig. 14, since the solder 51 is provided on the outlet 41b in addition to the outlet 41b of the terminal hole 41 of the conducting substrate 40, the amount of the solder 51 increases as compared with the case of fig. 13, and the solder reliably enters the entire gap between the external connection terminal 24 and the terminal hole 41. Note that, in order to adjust the amount of the molten solder 51 to be immersed, the amount of the solder 51 disposed on the outlet 41b can be appropriately adjusted. The solder 50 obtained by solidifying the solder 51 that has thus entered the gap between the external connection terminal 24 and the terminal hole 41 securely joins the external connection terminal 24 to the terminal hole 41 as shown in fig. 5A.

Next, a specific example of the semiconductor device having the conductive substrate to which the external connection terminals are not penetratingly bonded as described above will be described with reference to fig. 15 and 16. Fig. 15 and 16 are diagrams showing an example of the semiconductor device according to the first embodiment.

As shown in fig. 15, the semiconductor device 1a includes a plurality of semiconductor modules 10, capacitors 75 and 76, and a cooler 70. The plurality of semiconductor modules 10 and the capacitors 75 and 76 are electrically connected via the bus bar 60. The semiconductor device 1a includes a gate driving unit, which is not shown. In fig. 15, only 1 semiconductor module 10 is shown to show the side surface of the semiconductor device 1 a.

A plurality of semiconductor modules 10 may be arranged on the cooler 70. As described above, the semiconductor module 10 includes the first semiconductor element 14, the second semiconductor element 15, the third semiconductor element 16, and the fourth semiconductor element 17, and functions as a 2-level inverter. The capacitors 75 and 76 are smoothing capacitors that attenuate ripple currents generated by the switching operation of the first semiconductor element 14 and the third semiconductor element 16. The bus bar 60 has a first surface 60a and a second surface 60b integrally connected to the first surface 60a at right angles. The capacitors 75 and 76 are electrically connected to the inner side (semiconductor module 10 side) of the first surface 60a, and the other ends of the external connection terminals 23, 24, and 25 extending from the semiconductor module 10 are joined to the rear surface of the second surface 60 b. The gate driving unit insulates the input control signal, and converts the insulated control signal, for example, a PWM (pulse width modulation) signal, into a gate signal for driving the semiconductor module 10, and outputs the gate signal.

In this way, since the semiconductor device 1a can mount the external connection terminals 23, 24, and 25 of the semiconductor module 10 so as not to protrude from the second surface 60b of the bus bar 60 as in fig. 5 to 11 described above, the restriction of the space on the second surface 60b of the bus bar 60 is suppressed. This allows capacitors 75 and 76 to be mounted on first surface 60a of bus bar 60 in close proximity to second surface 60 b. Therefore, the semiconductor device 1a can be made thinner in fig. 15, and can be made smaller.

In the semiconductor device 1a, as shown in fig. 16, the capacitors 75 and 76 may be mounted outside the first surface 60a (on the opposite side of the semiconductor module 10). When the capacitors 75 and 76 are arranged in this manner, the semiconductor device 1a can suppress the limitation of the space on the second surface 60b of the bus bar 60, and thus, for example, the handling can be performed by a tool or a hand operation from the right side in fig. 16, and the operability is improved.

[ second embodiment ]

In the second embodiment, a case of a printed circuit board will be described as a conducting board with reference to fig. 17. Fig. 17 is a diagram for explaining the bonding of the external connection terminals to the printed circuit board according to the second embodiment. Fig. 17 is a cross-sectional view taken along a single-dot chain line Z-Z in fig. 4. Fig. 17 (a) and 17 (B) show different forms of the printed circuit board. In the second embodiment, the case of the external connection terminals 21a and 22a as the control terminals among the external connection terminals of the semiconductor module 10 will be described.

The printed circuit board 80 is a double-sided printed circuit board on which 2 conductive layers 81b and 81c are formed. The printed circuit board 80 includes an insulating layer 81a and conductive layers 81b and 81c provided on the front and back surfaces of the insulating layer 81a, and protective layers 81d and 81e are formed on the surfaces of the conductive layers 81b and 81c, respectively. The printed circuit board 80 is formed with a through hole 82 that penetrates from the inlet 82a on the back surface to the outlet 82b on the front surface.

As shown in fig. 17 (a), the through-hole 82 is hollow in a columnar shape without forming a protrusion or a step on the inner peripheral surface. The inlet 82a and the outlet 82b of the through-hole 82 face each other, and have the same shape and the same area, respectively. The through-holes 82 into which the external connection terminals 21a and 22a are fitted can have the conductive layers 81b and 81c exposed on the inner wall surfaces thereof. A plating film 83 made of a metal may be formed on the inner wall surface of the through hole 82 to cover the conductive layers 81b and 81c exposed from the inner wall surface. In the through hole 82 on the left side of fig. 17 (a), the conductive layer 81c on the inlet 82a side is exposed from the inner wall surface of the through hole 82, covered with the plating film 83, and electrically connected to the plating film 83. The conductive layer 81b on the outlet 82b side is not exposed from the inner wall surface of the through hole 82, but is electrically insulated from the plating film 83. On the other hand, in the through hole 82 on the right side in fig. 17 (a), the conductive layer 81c on the inlet 82a side is not exposed from the inner wall surface of the through hole 82, and is electrically insulated from the plating film 83. The conductive layer 81b on the outlet 82b side is exposed from the inner wall surface of the through hole 82, covered with the plating film 83, and electrically connected to the plating film 83.

A case where the printed circuit board 80 is mounted on the external connection terminals 21a and 22a of the semiconductor module 10 will be described. The external connection terminals 21a, 22a have projecting portions 21aa, 22aa formed inside the steps 21ae, 22ae formed in the peripheral portion of the distal end surface. The protruding portions 21aa and 22aa of the external connection terminals 21a and 22a are fitted to the through-holes 82 via the solder 50, and the steps 21ae and 22ae formed in the peripheral portions of the external connection terminals 21a and 22a abut against the edge portions of the inlets 82a of the through-holes 82 of the printed circuit board 80. The external connection terminals 21a and 22a can be connected to through holes (left and right through holes in fig. 17 a) electrically connected to the other conductive layers 81b and 81c, respectively. The external connection terminals 21a and 22a are joined to the through hole 82 of the printed circuit board 80. The other ends of the external connection terminals 21a and 22a are left in the through holes 82. Therefore, the external connection terminals 21a and 22a can be electrically connected to the conductive layers 81b and 81c without penetrating the printed circuit board 80. The plurality of external connection terminals 21a and 22a may be connected to the conductive layers 81c and 81b of the multilayer laminated substrate in which the plurality of conductive layers are laminated.

As shown in fig. 17 (B), the printed circuit board 80 can be provided with a step 82c from the entrance 82a to the exit 82B by drilling the insulating layer 81a of the printed circuit board 80 from the entrance 82a side of the through-hole 82. The step 82c is formed so as to surround the inner circumference of the through hole 82. The other end portions of the columnar external connection terminals 21a and 22a can be fitted into the through-holes 82. At this time, the peripheral portions 21ab and 22ab of the distal end surfaces of the other end portions of the external connection terminals 21a and 22a are brought into contact with the step 82c and fixed by the solder 50 in the gaps between the external connection terminals 21a and 22a and the through holes 82. The other ends of the external connection terminals 21a and 22a are left in the through holes 82. Therefore, the external connection terminals 21a and 22a can be electrically connected to the conductive layers 81b and 81c without penetrating the printed circuit board 80. The plurality of external connection terminals 21a and 22a can be connected to the conductive layers 81c and 81b of the multilayer laminated substrate in which the plurality of conductive layers are laminated. The external connection terminals 21a and 22a may have the protrusion 24a on the distal end surface, as in the case of fig. 7 (a).

Note that, as a method of joining the external connection terminals 21a and 22a to the printed circuit board 80 shown in fig. 17, the method shown in fig. 12 to 14 of the first embodiment may be used as needed, and the shapes of the other end portions of the external connection terminals 21a and 22a may be made different according to the method. The method shown in fig. 12 to 14 of the first embodiment can be applied to the case of a single layer or three or more layers without being limited to the case of two layers of the printed circuit board 80, and the shapes of the other end portions of the external connection terminals 21a and 22a can be made different according to this method.

[ third embodiment ]

In the third embodiment, a case where 2 stacked via boards are provided in the semiconductor module 10 will be described with reference to fig. 18 to 22. Fig. 18 and 20 are views for explaining a plurality of semiconductor modules mounted with bus bars according to the third embodiment. Fig. 19, 21, and 22 are views for explaining the joining of the external connection terminal to the bus bar according to the third embodiment. Fig. 19, 21 and 22 show enlarged areas of the broken lines shown in fig. 18 and 20.

As shown in fig. 18, the semiconductor device includes a via substrate 61 corresponding to the + side input substrate, a via substrate 62 corresponding to the-side input substrate, a via substrate 63 corresponding to the output substrate, and a printed circuit board 80 corresponding to the control substrate. The conductive substrates 61-63 and the printed circuit board 80 are flat. The conductive substrates 61 and 62 are laminated via an insulating paper 64 (described later). When the conductive substrates 61 to 63 are mounted on the external connection terminals 23 to 25 of the plurality of semiconductor modules 10, the other end (front end surface) of the external connection terminal 23 on which the conductive substrate 61 is mounted is made higher than the other end (front end surface) of the external connection terminal 24 on which the conductive substrate 62 is mounted. In addition, the conductive substrate 61 has an upper opening 61a formed in a region corresponding to the external connection terminal 24. The conductive substrate 62 is formed with lower openings 62a through which the external connection terminals 23 are inserted without contact. The position (height) of the other end (front end surface) of the external connection terminal 25 is the same as the other end (front end surface) of the external connection terminal 23 or is lower than the other end (front end surface) of the external connection terminal 23. The position (height) of the conductive substrate 63 is the same as that of the conductive substrate 61 or lower than that of the conductive substrate 61.

As shown in fig. 19, terminal holes 41 are formed in the conductive substrates 61 and 62, and the external connection terminals 23 and 24 are connected thereto. As in the case of fig. 6 (a), the conductive substrates 61 and 62 are each formed with a terminal hole 41 extending from the inlet 41a on the rear surface through the outlet 41b on the front surface on the opposite side of the rear surface. Further, the peripheral portions of the distal end surfaces of the other end portions of the external connection terminals 23, 24 are formed with steps 23e, 24 e. At this time, the projections 23a and 24a of the external connection terminals 23 and 24 are fitted into the terminal hole 41 via the solder 50. The steps 23e and 24e formed in the peripheral portions of the distal end surfaces of the other end portions of the external connection terminals 23 and 24 are abutted against the edge portion of the inlet 41a of the terminal hole 41 and fixed by the solder 50 in the gap between the external connection terminal 24 and the terminal hole 41. Therefore, the external connection terminals 24 can be electrically connected to the conductive substrate 62 without penetrating the conductive substrate 62. The external connection terminals 23 may be electrically connected to the conductive substrate 61 without penetrating the conductive substrate 61. In this way, since the external connection terminals 23 and 24 of the semiconductor module 10 can be mounted so as not to protrude from the conductive substrate 61, the restriction of the space on the conductive substrate 61 is suppressed. Similarly, the external connection terminals 25 can be electrically connected to the conductive substrate 63 without penetrating the conductive substrate 63. At this time, the conductive substrates 61 and 62 hold the insulating paper 64 therebetween, and the insulating properties of the conductive substrates 61 and 62 are maintained. The upper opening 61a and the lower opening 62a are kept at a sufficient distance from the external connection terminals 24, 23, respectively. The insulating paper 64 has through holes formed in regions including all the terminal holes 41. The through hole of the insulating paper 64 is larger than the terminal hole 41. The through hole of the insulating paper 64 is preferably larger than the outer diameter of the external connection terminal 25. The upper opening 61a and the lower opening 62a are formed in a region including all the through holes of the insulating paper 64. The through hole of the insulating paper 64 is preferably smaller than the upper opening 61a and the lower opening 62 a. Thereby, the creeping distance with respect to the external connection terminals 23, 24 is sufficiently ensured.

On the other hand, the case of fig. 20 is also acceptable in order to mount the external connection terminals 23 to 25 of the semiconductor module 10 on the conductive substrates 61 to 63 so as not to protrude from the conductive substrates 61 to 63. In the case shown in fig. 20, when the conductive substrates 61 to 63 are mounted on the plurality of semiconductor modules 10, the front end surfaces of the external connection terminals 23 on which the conductive substrate 61 is mounted and the front end surfaces of the external connection terminals 24 on which the conductive substrate 62 is mounted are at the same height. In addition, as in the case of fig. 18, the conductive substrate 61 has an upper opening 61a formed in a region corresponding to the external connection terminal 24. The conductive substrate 62 is formed with lower openings 62a through which the external connection terminals 23 are inserted without contact. The position (height) of the other end (front end surface) of the external connection terminal 25 is the same as the other end (front end surface) of the external connection terminal 24 or lower than the other end (front end surface) of the external connection terminal 23. The position (height) of the conductive substrate 63 is the same as that of the conductive substrate 61 or lower than that of the conductive substrate 61.

As shown in fig. 21, terminal holes 41 are formed in the conductive substrates 61 and 62, and the external connection terminals 23 and 24 are connected thereto. At this time, the connection of the via substrate 61 and the external connection terminal 23 may be the same as the case of fig. 5A. The terminal hole 41 of the conductive substrate 61 is formed so as to penetrate from the inlet 41a on the rear surface to the outlet 41b on the front surface on the opposite side of the rear surface. In addition, a step 42 is formed from the inlet 41a to the outlet 41 b. At this time, the peripheral portion of the distal end surface of the other end portion of the external connection terminal 23 abuts on the step 42 and is fixed by the solder 50 in the gap between the external connection terminal 23 and the terminal hole 41. Therefore, the external connection terminals 23 can be electrically connected to the conductive substrate 61 without penetrating the conductive substrate 61. The external connection terminals 25 can be electrically connected to the conductive substrate 63 without penetrating the conductive substrate 63 in the same configuration. On the other hand, as shown in fig. 21, the conductive substrate 62 and the external connection terminal 23 are connected to each other through a columnar terminal hole 41. The linear external connection terminals 24 are inserted into the terminal holes 41 of the conductive substrate 62, and the distal end surfaces thereof are located below the front surface of the conductive substrate 61. The external connection terminals 24 are fixed to the terminal holes 41 by solder 50. In this way, the external connection terminals 23 and 24 of the semiconductor module 10 can be mounted so as not to protrude from the conductive substrate 61, and therefore, the restriction of the space on the conductive substrate 61 is suppressed. At this time, the conductive substrates 61 and 62 hold the insulating paper 64 therebetween, and the insulating properties of the conductive substrates 61 and 62 are maintained. At this time, the upper opening 61a and the lower opening 62a are kept at a sufficient distance from the external connection terminals 24, 23, respectively. Thereby, the creeping distance with respect to the external connection terminals 24, 23 is sufficiently ensured.

In the modification example to fig. 21, as shown in fig. 22, the conductive substrates 61 and 62 are shaped such that the regions including the positions where the external connection terminals 23 and 24 are bonded are recessed toward the upper opening 61a and the lower opening 62 a. More specifically, the upper-level conductive substrate 61 has a shape in which a region including the position where the external connection terminal 23 is bonded is recessed toward the lower opening 62 a. That is, the conductive substrate 61 is formed with a recess in which the terminal hole 41 is recessed toward the lower opening 62 a. The lower conductive substrate 62 is shaped such that a region including the position where the external connection terminal 24 is bonded is recessed toward the upper opening 61 a. That is, the conductive substrate 62 is formed with a recess in which the terminal hole 41 is recessed toward the upper opening 61 a. The front end surface of the external connection terminal 23 to which the conductive substrate 61 is attached and the front end surface of the external connection terminal 24 to which the conductive substrate 62 is attached are at the same height. At this time, the connection of the via substrate 61 and the external connection terminal 23 and the connection of the via substrate 62 and the external connection terminal 24 may be the same as in the case of fig. 5A. The terminal holes 41 of the 2 conductive substrates 61 and 62 are formed so as to penetrate from the inlet 41a on the back surface to the outlet 41b on the front surface on the opposite side of the back surface. In addition, a step 42 is formed from the inlet 41a to the outlet 41 b. At this time, the peripheral portions of the distal end surfaces of the other end portions of the 2 external connection terminals 23, 24 are respectively brought into contact with the step 42, and the external connection terminals 23, 24 are fixed by the solder 50 in the gaps of the terminal holes 41. Therefore, the external connection terminals 23 and 24 can be electrically connected to the conductive substrates 61 and 62 without penetrating the conductive substrates 61 and 62. Note that, a concave portion may be formed in at least one of the conductive substrate 61 and the conductive substrate 62. In addition, the front end surface of the external connection terminal 23 may be higher than the front end surface of the external connection terminal 24.

The conductive substrates 61 to 63 and the external connection terminals 23, 24, and 25 shown in fig. 18 to 22 may have the configurations shown in fig. 5 to 11 of the first embodiment. In addition, as the method for connecting the external connection terminals 23, 24, and 25 to the conductive substrates 61 to 63 shown in fig. 18 to 22, the method shown in fig. 12 to 14 of the first embodiment can be used. In the conductive substrates 61 to 63 shown in fig. 18 to 22, for example, when the surfaces are coated with an insulating coating, the areas of the upper opening 61a and the lower opening 62a can be made smaller than those in fig. 18 to 22. The conductive substrate 63 to which the external connection terminal 25 serving as the O terminal is connected may be laminated on the conductive substrates 61 and 62 in the same laminated state as the conductive substrates 61 and 62 to which the external connection terminals 23 and 24 serving as the P, N terminals are connected. In addition, the connection of the external connection terminals 25 may be the same as the external connection terminals 23, 24. Other suitable wiring shapes and connection forms may be adopted depending on the type of circuit and the like.

[ fourth embodiment ]

In the first to third embodiments, the case where the conductive substrate is mounted on the external connection terminal extending from the semiconductor module 10 will be described. In the fourth embodiment, a conductive substrate connected in a semiconductor module will be described with reference to fig. 23. Fig. 23 is a sectional view of a semiconductor module of the fourth embodiment. In the configuration included in the semiconductor module 10a of fig. 23, the same components as those included in the semiconductor module 10 and the like described above are denoted by the same reference numerals, and the description thereof will be omitted. The semiconductor module 10a has the same function as the semiconductor module 10.

The semiconductor module 10a includes first to fourth semiconductor elements 14 to 17, a package 30 for packaging the first to fourth semiconductor elements 14 to 17, conductive posts 19 and 20 electrically connected to the first to fourth semiconductor elements 14 to 17, the first circuit board 12a and the second circuit board 12b in the package 30, and external connection terminals 21a, 21b, 22a, 22b, 23, 24 and 25. In fig. 23, the external connection terminals 21b and 22b are not shown. The semiconductor module 10a includes a first insulating substrate 11A and a second insulating substrate 11B arranged side by side in the horizontal direction. A first circuit board 12a is disposed on the upper surface of the first insulating substrate 11A, and a metal plate 13 having the same thickness is disposed on the rear surface. Further, a second circuit board 12B is disposed on the upper surface of the second insulating substrate 11B, and a metal plate 13 having the same thickness is disposed on the rear surface. Further, a plurality of third circuit boards are arranged on the upper surfaces of the first insulating substrate 11A and the second insulating substrate 11B. As shown in fig. 2, the metal plate 13 is exposed from the back surface of the sealing portion 30.

The conductive substrates 71 and 72 are provided above the first circuit board 12a and the second circuit board 12b via an insulating substrate 74, and are sealed by the sealing portion 30. The conductive substrates 71 and 72 and the insulating substrate 74 are flat plates like the conductive substrates 61, 62, and 63 and the insulating paper 64 in fig. 18.

When the conductive substrates 71 and 72 are mounted on the conductive posts 19 and 20 of the semiconductor module 10a, the other end portions (distal end surfaces) of the conductive posts 19 and 20 on which the conductive substrate 71 is mounted are made higher than the other end portions (distal end surfaces) of the conductive posts 20 on which the conductive substrate 72 is mounted. In the conductive substrate 71, an upper opening 71a is formed in a region corresponding to the conductive posts 19 and 20 mounted on the conductive substrate 72. The conductive substrate 72 is formed with a lower opening 72a through which the conductive posts 19 and 20 mounted on the conductive substrate 71 are inserted without contact.

Further, terminal holes 41 are formed in the main surfaces of the conductive substrates 71 and 72 on the sides facing the first circuit board 12a and the second circuit board 12b, and the conductive posts 19 and 20 are connected thereto, as in the third embodiment. Further, a terminal hole 41 is formed in a main surface of the conductive substrate 71 opposite to the main surface, and the external connection terminals 21a and 22a are connected thereto. Fig. 23 shows the same shape of the terminal hole 41 as in the case of fig. 5A. Not limited to this, the conductive substrates 71 and 72 and the conductive posts 19 and 20 shown in fig. 23 may have the structures shown in fig. 5B to 11 of the first embodiment, as in the third embodiment. The conductive substrates 71 and 72 and the insulating substrate 74 have through holes through which the external connection terminals 23, 24, and 25 are inserted.

As shown in fig. 23, the insulating substrate 74 has a through hole formed in a region corresponding to the terminal hole 41. The through hole of the insulating substrate 74 is larger than the terminal hole 41. The through hole of the insulating substrate 74 is preferably larger than the outer diameter of the conductive posts 19, 20. The upper opening 71a and the lower opening 72a are formed in a region including all the through holes of the insulating substrate 74. The through hole of the insulating substrate 74 is preferably smaller than the upper opening 71a and the lower opening 72 a. This ensures a sufficient creeping distance with respect to the conductive posts 19, 20.

In the semiconductor module 10a, as in the case shown in fig. 21, the conductive posts 19 and 20 mounted on the conductive substrate 72 can be inserted through the terminal holes 41 of the conductive substrate 72, and the distal end surfaces thereof can be positioned below the front surface of the conductive substrate 71. The conductive posts 19 and 20 are also fixed to the terminal holes 41 by solder. At this time, the upper opening 71a and the lower opening 72a are kept at a sufficient distance from the conductive posts 19, 20, respectively. This ensures a sufficient creeping distance with respect to the conductive posts 19, 20.

In the semiconductor module 10a, as in the case shown in fig. 22, the conductive substrates 71 and 72 may be shaped such that the region including the position where the conductive posts 19 and 20 are bonded is recessed toward the upper opening 71a and the lower opening 72 a. The shape of the recess may be formed in at least one of the conductive substrate 71 and the conductive substrate 72. The end surfaces of conductive posts 19 and 20 mounted on conductive substrate 71 may be higher than the end surfaces of conductive posts 19 and 20 mounted on conductive substrate 72.

Fig. 23 merely shows a case where the external connection terminals 21a and 22a are connected to the conductive substrate 71. The external connection terminals 21a and 22a can be connected to a third circuit board in the same manner as the semiconductor module 10 of fig. 3. The conductive boards 71 and 72 are not limited to the conductive wires of the main circuit and the signal wires. In fig. 23, a case where the conductive substrate 71 and the conductive substrate 72 are formed of two layers and an insulating paper 74 in between is described. Not limited to this, the conductive substrates 71 and 72 may be a printed circuit board integrated with an insulating plate. The printed circuit board in this case can be connected to the conductive posts 19 and 20 by the method described in the second embodiment. The conductive substrate is not limited to two layers, and may have a single-layer structure or a multilayer structure having three or more layers.