JP2000236677A - Semiconductor stack - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a semiconductor stack employing a switching element, having high breakdown strength in which wiring structure is simplified, while enhancing insulation performance and assembling performance. SOLUTION: An AC conductor 4, having one end part bent in the vertical direction to form an AC terminal L, an inner insulator 5, first and second flexible insulators 6, 7 having L-shaped cross-section, and P-side and N-side conductors 8, 9 which are bent in the vertical direction and further bent in the horizontal direction to have a U-shaped cross-section are laminated sequentially on a bottom insulator, having a sidewall 3a and a rib 3b mounted on each main electrode face S1, S2 of first and second switching elements 1, 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a low-inductance wiring structure of a semiconductor stack composed of switching elements such as IGBTs, and more particularly, to a low-inductance wiring structure having high reliability and good maintainability. A semiconductor stack is provided.

[0002]

2. Description of the Related Art Generally, in an inverter stack formed by connecting switching elements, in order to suppress an overvoltage applied to the switching elements, a closed circuit including an electrolytic capacitor or a snubber circuit of a DC power supply circuit and the switching elements is provided. Minimizing the inductance has become a very important issue in wiring. This is because it is possible to omit a snubber circuit connected to suppress overvoltage of the element and to reduce the snubber capacity, and there is a great advantage that the size and cost of the inverter device can be reduced.

FIG. 6 shows an electrical configuration of a general single-phase inverter circuit configured by connecting switching elements 1, 2, 23 and 24 (FIG. 6 shows an embodiment of the present invention). 1). Here, an example is shown in which the switching elements 1, 2, 23, 24 are made of IGBTs.
Are represented by symbols G1, G2, G3, and G4, respectively.
The symbol C is a collector, and E is an emitter. Also, P,
N is a DC input plus terminal (P terminal) and a minus terminal (N terminal), respectively, and L1 and L2 are output terminals (AC terminals). 25 is a snubber capacitor Cs,
26 is an electrolytic capacitor Ce.

In an inverter stack constituting such an inverter circuit, for example, Cs → G1 → G2 →
Closed circuit from Cs, Cs → G3 → G4 → Cs or Ce →
It is important to reduce the inductance of the closed circuit from G1 → G2 → Ce and Ce → G3 → G4 → Ce.

To achieve this, for example, Japanese Patent Application Laid-Open
As shown in JP-A-19-19245, generally, a flat conductor is used as a wiring conductor of each part in a stack, and these are opposed to each other at a short distance via an insulating layer to form a reciprocating line.

FIG. 7 shows an IGBT (corresponding to a first switching element) G in the single-phase inverter circuit shown in FIG.
FIG. 1 is a diagram showing an embodiment of a conventional low-inductance wiring structure stack that forms an alternate long and short dash line including an IGBT (corresponding to a second switching element) G2 (hereinafter, referred to as a half bridge). ) Is a top view,
(B) is a sectional view taken along the line AA shown in the top view (a).

In FIG. 7, 1 and 2 are IGB, respectively.
T elements G1 and G2, both of which are mounted and fixed on the heat sink 20. Also, 31,
33, 35 and 37 are insulating plates, 32 is an AC conductor, 34 is a P-side conductor, 36 is an N-side conductor, 32a and 32b are cylindrical conductors connected to the AC conductor 32, and 34a and 36a are also P-side conductors 34 respectively. , N-side conductor 36. 12 is a cylindrical conductor 32a, 36a, 34a,
32b is connected to the emitter terminals E of the switching elements G1 and G2.
And a tightening screw for connecting to the collector terminal C. Insulating plates 31, 33, 35, 37 and conductors 32, 3
Since the layers 4 and 36 are laminated and fixedly integrated by bonding or the like, they are called laminated conductors.

Here, the P and N side terminals and the AC terminal 3
7, 36 and 32 project in the vertical direction in FIG. 7A, but because the control terminals G1 and G2 are provided in the left and right direction in FIG. Because you can't.

In FIG. 7, a closed circuit constituting a half bridge is composed of a P-side conductor 34 → cylindrical conductor 34a → collector terminal C of switching element 1 (G1) → inside switching element G1 → emitter terminal E of switching element G1.
→ cylindrical conductor 32a → AC conductor 32 → cylindrical conductor 32b →
The path is formed from the collector terminal C of the switching element 2 (G2) → the inside of the switching element G2 → the emitter terminal E of the switching element G2 → the cylindrical conductor 36a → the N-side conductor 36.

[0010] As described above, by laminating the flat conductors with the insulating layer interposed therebetween, it is possible to reduce the inductance of the wiring.

[0011]

However, the conventional wiring structure using the laminated conductor configured as described above has the following problems.

(1) The entirety of the laminated portion is a conductor portion 3
Since there are four layers and four insulating portions, the processing of each laminated member becomes complicated, and the member cost increases.

(2) Between the emitter and the collector of the switching element (that is, the cylindrical conductor 32a-3 of the laminated conductor)
The outer creepage distance of the insulator existing between (2b) is shorter than the recent high-breakdown-voltage element, and there is a problem in insulation performance.

(3) In the full-surface laminated conductor structure, since the input / output terminals (P, N side terminals and AC terminals) are taken out from the end face of the laminated conductor, two or three half bridge stacks are connected. , When a single-phase bridge or a three-phase bridge circuit is to be constructed,
External connection of the side conductor is not easy. Therefore, it is necessary to manufacture a laminated conductor for a single-phase bridge for a single-phase bridge and for a three-phase bridge for a three-phase bridge, that is, collectively for each circuit.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to reduce the number of layers, to provide excellent insulation, to facilitate assembly, and to facilitate external connection. It is to provide a semiconductor stack.

[0016]

The invention according to claim 1 is
A semiconductor stack forming a half bridge by mounting a first and second switching element on a heat sink and connecting the first and second switching elements in series with each other, wherein a first electrode terminal of the first switching element is provided. A bottom insulator, an AC conductor, and an internal insulation on a surface of the first switching element and on a first electrode terminal surface of the second switching element adjacent to the first electrode terminal face of the first switching element. The first flexible insulator and the P-side conductor are sequentially laminated on a portion on the side of the first switching element in the surface of the internal insulator, and the body is laminated in the surface of the internal insulator. A second flexible insulator and an N-side conductor are sequentially laminated on a portion on the side of the second switching element, and the first flexible insulator and the inner insulator thereunder are provided. One of the P-side conductors penetrates the AC conductor and the bottom insulator, contacts the first electrode terminal surface of the first switching element, and is insulated from the AC conductor via a conductor spacer. The end of the first
A first projection connected to a first electrode terminal of the switching element and provided at a portion on one end side of the AC conductor penetrates the bottom insulator thereunder and the first projection of the first switching element. The second convex portion, which is in contact with the two-electrode terminal surface and is provided at the other end of the AC conductor, penetrates the bottom insulator thereunder and provides the first switching element of the second switching element.
One end of the N-side conductor extends beyond the end surface of the internal insulator toward the second electrode terminal surface of the second switching element, and is in contact with the electrode terminal surface; The one end of the N-side conductor is connected to a second electrode terminal of the second switching element via a conductive spacer for the N-side conductor in contact with the second electrode terminal surface of the element. One end of the first flexible insulator extending in a direction perpendicular to the first and second electrode terminal surfaces of the first switching element, between the P-side conductor and the N-side conductor; One end of the second flexible insulator extending in a direction perpendicular to the first and second electrode terminal surfaces of the second switching element and in parallel with the one end of the first flexible insulator; Is insulated by And wherein the door.

The invention according to claim 2 is the semiconductor stack according to claim 1, wherein a peripheral end of the bottom insulator is
The cross section is configured as an L-shaped side wall, and the AC conductor is mounted on a surface of the bottom insulator surrounded by the side wall.

According to a third aspect of the present invention, in the semiconductor stack according to the first or second aspect, the rib that fits into the groove between the first and second electrode terminal surfaces of the first switching element has the bottom portion. It is characterized by being formed on an insulator.

A fourth aspect of the present invention is the semiconductor stack according to any one of the first to third aspects, wherein the semiconductor stack is located above a groove between the first and second electrode terminal surfaces of the first switching element. On the surface of the internal insulator, a rib protruding upward is formed integrally with the internal insulator,
The first flexible insulator and the P-side conductor are sequentially stacked on the surface of the internal insulator inside the rib of the internal insulator.

According to a fifth aspect of the present invention, in the semiconductor stack according to any one of the first to fourth aspects, the other of the second flexible insulator on the side of the second electrode terminal of the second switching element. Is inserted into the groove between the first and second electrode terminal surfaces of the second switching element while being separated from the one end of the N-side conductor beyond the end surface of the internal insulator. It is characterized by having been done.

According to a sixth aspect of the present invention, in the semiconductor stack according to any one of the first to fifth aspects, at least the bottom insulator, the AC conductor, and the internal insulator are integrally formed. It is characterized by the following.

The invention according to claim 7 is the semiconductor stack according to any one of claims 1 to 6, wherein the one end of the AC conductor is connected to the first and second switching elements of the first switching element. The P-side conductor and the N-side are bent in a direction perpendicular to the two-electrode terminal surface to form an AC terminal.
Each of the side conductors is connected to the one end of the first flexible insulator from a substantially central portion between the first electrode terminal surface of the first switching element and the first electrode terminal surface of the second switching element. The second flexible insulator is bent in a vertical direction so as to be parallel to each other via the one end of the second flexible insulator, and the one end of the first flexible insulator and the one of the second flexible insulator are further bent. The other end of the P-side conductor and the other end of the N-side conductor are P and P, respectively, which are bent in the horizontal direction so that the cross-sectional shape becomes a U-shape apart from one end. It is characterized in that an N terminal is formed.

[0023]

(Embodiment 1) Hereinafter, Embodiment 1 of the present invention will be described with reference to FIGS. FIGS. 1A and 1B are embodiments of a half-bridge stack indicated by a dashed line in the circuit diagram of FIG. 6, and FIG. 1A is a top view and FIG. b) is AA of (a)
It is a longitudinal cross-sectional view about a line.

In FIG. 1, reference numeral 1 denotes a first IGBTG, for example.
The first switching element 2 is composed of, for example, a second IG
This is a second switching element made of BTG2. Both elements 1 and 2 are mounted on a heat sink 20 and connected in series with each other to form a half bridge. S1 and S2 are the first and second main electrode surfaces of the first and second switching elements 1 and 2, respectively, and both surfaces S1 and S2 have the same dimensions (same height) and the same shape. That is, the first main electrode surface S1 is connected to the emitter terminal (the second
A convex emitter terminal surface (second electrode terminal) connected to an electrode terminal E
Electrode terminal surface) S1E and collector terminal (first electrode terminal)
C, and a convex collector terminal surface (first electrode terminal surface) S1C of the same height. At the same time, the second main electrode surface S2 is connected to the collector terminal (first electrode terminal) C of the second switching element 2 and is adjacent to the surface S1C and faces the collector terminal surface (first electrode terminal surface) S2C.
And an emitter terminal surface (second electrode terminal surface) S2E connected to the emitter terminal (second electrode terminal) E.

Reference numeral 3 denotes the terminal surfaces S1E, S1C, S2
C is a bottom insulator mounted on C, and 4 is a bottom insulator 3
Side wall 3a formed by bending the peripheral end portion of
An AC conductor laminated on the surface of the same part 3 surrounded by a circle, one end of the AC conductor 4 is bent in the vertical direction to form an AC terminal L projecting to the outside, In the vicinity of the end portion, a first convex portion 4a penetrating the bottom insulator 3 thereunder and contacting the emitter terminal surface S1E is formed. On the other hand, the other end of the AC conductor 4 is formed with a second convex portion 4b which also penetrates the bottom insulator 3 therebelow and contacts the collector terminal surface S2C. Numeral 5 is laminated on the surface of the AC conductor 4 surrounded by the side wall 3a, and has one end (corresponding above the groove between the emitter terminal surface S1E and the collector terminal surface S1C) having a convex shape. Is an internal insulator provided with the rib 5a.

Further, reference numerals 6 and 7 denote first and second flexible insulators formed so as to have an L-shaped cross section, respectively.
C and the first and second switching elements 1,
The two insulators are laminated on respective portions in the surface of the internal insulator 5, and both ends of both insulators 6 and 7 are connected from the central portion to the terminal surfaces S 1 E and S 1.
They are folded in a direction perpendicular to C, S2C, and S2E and overlapped. Moreover, the other end 7b of the second flexible insulator 7 is fitted into the groove between the two terminal surfaces S2C and S2E beyond the end face or the side wall 3a of the internal insulator 5. Further, 8 is a first flexible insulator 6
Is a P-side conductor laminated on the surface of one of the above, one end of which is close to the rib 5a, and the other end is bent in the vertical direction near the center and further horizontally. It is bent to have a U-shaped cross section, and the other end forms a P terminal. Reference numeral 9 denotes an N-side conductor laminated on the surface of the second flexible insulator 7, one end of which is beyond the end face of the internal insulator 5 and is connected to the emitter terminal surface S2E via the conductive spacer 9a. Contact, the other end side is bent in the vertical direction near the center, and further bent in the horizontal direction, the cross-sectional shape is U-shaped, the other end is Makes N terminal.

Reference numeral 10 denotes an insulating spacer, 11 denotes a conductor spacer, 12 denotes a fastening screw, and 20 denotes a heat sink.

FIG. 2A is a top view of the bottom insulator 3 of FIG. 1, and FIG. 2B is a cross-sectional view taken along line AA of FIG. In FIG. 2, 3a indicates the above-described side wall portion which is a feature of the present invention, and 3b indicates a rib formed in a convex shape so as to be fitted in a groove between both terminal surfaces S1E and S1C. , 3C1 to 3C3 indicate through holes having the same diameter as the first convex portion 4a, the conductive spacer 11, and the second convex portion 4b, respectively.

FIG. 3 is an exploded sectional view of members 4 to 12 which are sequentially laminated and assembled on the bottom insulator 3 in the constituent members shown in FIG. In FIG. 3, one end side vicinity 4a and the other end 4b of the AC conductor 4 are provided with:
First and second switching elements having contact surfaces connected to the emitter and collector terminals E and C of the first and second switching elements 1 and 2, respectively.
Protrusions are formed. The AC conductor 4 is bent in the vertical direction at one end adjacent to the first protrusion 4a to form an AC terminal L. In addition, FIG.
The rib 5a and the through holes 5C1 and 5C2 having substantially the same diameter as the spacers 10 and 11 are also formed at one end corresponding to the right end of the internal insulator 5. The first and second flexible insulators 6 and 7 are, for example, highly flexible insulating sheets, and can be bent along the flat conductors (3, 4, 5) for the insulators 6 and 7. can do. Further, as shown in FIG. 3, the P-side conductor 8 and the N-side conductor 9 are processed so that the vertical cross-sectional shape becomes a U-shape, and P and N terminals are formed at the other end corresponding to the upper surface. are doing. A portion 9 a formed at one end of the N-side conductor 9 is a conductive spacer for the N-side conductor connected to the emitter terminal E of the second switching element 2.

The semiconductor stack shown in FIG.
11 can be sequentially laminated and assembled, but five members of the bottom insulator 3, the AC conductor 4, the internal insulator 5, the insulating spacer 10, and the conductive spacer 11 (at least the bottom insulator 3, the AC conductor 4, the internal It is desirable that the three members of the insulator 5) be integrated beforehand by fixing or molding. FIG. 4 shows these members 3, 4, 5, 1
An example in which 0 and 11 are integrated by fixing is shown. Here, reference numeral 13 denotes an adhesive having excellent insulating properties, for example, a resin or a rubber-based material. The adhesive 13 is important for fixing the above members and also filling a gap between the conductive spacer 11 connected to the AC conductor 4 and the DC conductor (P-side conductor 8) to enhance insulation. Play a role.

To assemble the semiconductor stack of FIG.
First, the above-mentioned integrated assembly shown in FIG. 4 is connected to first and second switching elements 1 (G1) and 2 (G1).
2) mounted on the main terminal surfaces S1 and S2 of the two devices 1 and 2 in accordance with the positions of the terminal surfaces S1E, S1C and S2C, and the emitter terminal E of the first switching device 1 and the collector terminal of the second switching device 2 And C are fixed together by screws 12.

Next, the first flexible insulator 6 is fitted and placed in the conductor spacer 11, the P-side conductor 8 is placed thereon, and both members 6, 8 are screwed to the collector terminal C of the second switching element 2. Fix with 12.

Further, the second flexible insulator 7 is fitted and placed in the insulating spacer 10, and the other end 7b is fitted in the groove between the collector terminal surface S2C and the emitter terminal surface S2E of the second switching element 2. This portion 7b is an important portion for insulation measures as described later. Next, the N-side terminal 9 is fitted on the insulating spacer 10 and mounted on the surface of the second flexible insulator 7, and both parts 7, 9 are fixed to the emitter terminal E of the second switching element 2 by screws 12. As a result, the other end side portions of the P-side and N-side conductors 8 and 9 are separated from each other by the vertical portions formed in the middle thereof.
The upper portions 6a and 7a of the first and second flexible insulators 6 and 7 are opposed to each other with the second flexible insulators 6 and 7 interposed therebetween. (Corresponding to the other ends of the side-side and N-side conductors 8, 9).

In the semiconductor stack of FIG. 1 according to the present invention, the closed circuit constituting the half bridge is composed of the P-side conductor 8 → conductive spacer 11 → first switching element 1 (G
1) Collector terminal C → inside the same element 1 (G1) → emitter terminal E of the same element 1 (G1) → first convex portion 4a → main body of AC conductor 4 → second convex portion 4b → second switching element 2
Collector terminal C of (G2) → Inside of the same element 2 (G2) →
The emitter terminal E of the element 2 (G2) → conductive spacer 9b
→ It is constituted by the path of N-side conductor 9.

Here, comparing the semiconductor stack of FIG. 1 with that of FIG. 7 of the conventional example, in this stack, the total number of laminated layers of the plate conductor and the insulator is only four, and the laminated structure is significantly simpler than the conventional example. It is clear that the cost of the members of the laminated structure can be significantly reduced. In particular, the emitter terminal surfaces S1E, S2 of the switching elements 1, 2
It can be seen that the upper part of E is much simpler than in the past.

According to the present invention, in order to improve the assemblability of the stack, as shown in FIG. 4, five members of a bottom insulator 3, an AC conductor 4, an internal insulator 5, an insulating spacer 10 and a conductor spacer 11 are previously provided. It has been proposed to integrate them by bonding or molding. This makes the assembly of the stack very easy.

In order to improve the insulation performance of the entire device, in the present stack, the side wall 3a and the rib 3
b. Here, the side wall 3a is extremely important for integrating the assembly of the five members 3 to 5, 10, and 11 shown in FIG. This has the effect of ensuring the insulation of the end face of the conductor 4 reliably. Also, rib 3
b is the collector terminal surface S1C of the first switching element 1.
And has a role of extending the creepage distance between them. Since switching devices with a withstand voltage of 3 kV to 4 kV have appeared in high withstand voltage switching devices,
When a flat surface as shown in FIG. 7 exists between the collector and the emitter of such a high breakdown voltage switching element, the creeping distance of the groove between the terminals of the switching element is impaired, and the insulation property may be significantly deteriorated. However, according to the present stack, it is possible to prevent such a problem from occurring due to the presence of the members 3a and 3b. As described above, the rib 5a formed on the internal insulator 5 also has the effect of increasing the creepage distance.

Another feature of the present invention resides in that a unique terminal shape and terminal arrangement are provided. That is, the AC conductor 4
Is bent perpendicularly from the vicinity of the emitter terminal surface S1E of the first switching element 1 to form an AC terminal L,
The P-side conductor 8 and the N-side conductor 9 are both switching elements 1,
2 is bent in the vertical direction so as to face each other via one end (vertical portion) of the first and second flexible insulators 6 and 7 from the substantially central portion, and further bent in the horizontal direction to have a cross-sectional shape. Has a U-shape, and the other end of each forms a P and N terminal. With the above configuration, two or three semiconductor stacks can be combined to easily connect single-phase bridges (single-phase inverters) or three-phase bridges (three-phase inverters). It is possible to FIG.
This is an example of a phase bridge, in which three half-bridge units shown in FIG. 1 are arranged side by side, and P-side terminals 8 of the three units are connected to each other by external DC conductors 27 and 28 having an L-shaped cross section. The N-side terminals 9 are connected to each other. An insulator 29 is inserted between the conductors 27 and 28.

Similarly, a plurality of the semiconductor stacks shown in FIG. 1 can be arranged side by side, and the respective P-side, N-side, and AC terminals can be easily connected in parallel by bus bars. On the contrary,
In the conventional structure as illustrated in FIG. 7, it is apparent that it is difficult to combine and connect a plurality of such devices.

In the present invention, the first and second flexible insulators 6 and 7 also work very effectively. This is because these members 6 and 7 can be bent along the P-side and N-side conductors 8 and 9 and the second flexible insulator 7 is provided between the emitter and collector of the second switching element 2 in the groove. The other end 7b of the
Collector terminal C of second switching element 2 and N-side conductor 9
This is because the insulation between them can be strengthened.

(Modifications) (1) In the first embodiment, a stack having a half-bridge configuration has been described.
It goes without saying that the phase bridge configuration can be applied to a collective wiring structure.

(2) Further, the present invention is not limited to the terminal arrangement of each switching element shown in the first embodiment.
It can be applied to switching elements of various shapes.

(3) As the first and second switching elements, other transistors such as MOSFETs and bipolar transistors may be used in addition to IGBTG1 and G2.

[0044]

According to the first aspect of the present invention, the total number of layers of each conductor and each insulator can be set to four layers.
Compared with the prior art, the laminated structure can be simplified, and the cost of the members in the laminated portion can be significantly reduced. In particular, the structure of the first and second switching elements on each second electrode terminal surface can be significantly simplified.

According to the second aspect of the present invention, the insulation of the end face of the AC conductor can be reliably ensured by the side wall of the bottom insulator, so that the insulation performance of the entire device can be improved as compared with the prior art. Can be.

According to the third aspect of the present invention, the creepage distance between the first electrode terminal and the second electrode terminal of the first switching element can be increased by the rib of the bottom insulator.
The insulation performance of the entire device can be improved as compared with the prior art.

According to the fourth aspect of the present invention, the creepage distance between the first electrode terminal and the second electrode terminal of the first switching element can be increased by the rib of the internal insulator.
The insulation performance of the entire device can be improved as compared with the prior art.

According to the fifth aspect of the present invention, the insulation between the first electrode terminal and the second electrode terminal of the second switching element can be enhanced, so that the insulation performance of the entire device can be improved as compared with the prior art. Can be improved.

According to the sixth aspect of the present invention, the integration of the semiconductor stack can be extremely facilitated by the integration.

According to the seventh aspect of the present invention, by combining another semiconductor stack having the same structure outside the semiconductor stack, it is possible to easily achieve a composite (improved applicability) of a single-phase bridge or a three-phase bridge. can do.

[Brief description of the drawings]

FIG. 1 is a diagram showing a wiring structure of a semiconductor stack according to a first embodiment of the present invention;

FIG. 2 is a view showing a bottom insulator serving as a component of the present invention.

FIG. 3 is an exploded cross-sectional view of constituent members excluding a bottom insulator shown in FIG.

FIG. 4 is a partially assembled sectional view of the wiring structure shown in FIG. 1;

FIG. 5 is a diagram showing a connection example of a three-phase bridge which is an application example of the present invention.

FIG. 6 is a diagram showing a main circuit of a single-phase inverter related to the description of the present invention.

FIG. 7 is a diagram showing a wiring structure of a conventional semiconductor device.

[Explanation of symbols]

1 1st switching element, 2nd switching element, 3 bottom insulator, 3a side wall, 3b, 5a rib,
4 AC conductor, 4a first convex portion, 4b second convex portion, 5
Internal insulator, 6 first flexible insulator, 7 second flexible insulator, 7b other end, 8P-side conductor,
9 N side conductor, L AC terminal, 9a, 11 conductive spacer, 10 insulating spacer, 20 heat sink.

Claims (7)

[Claims] 1. A semiconductor stack comprising a first bridge and a first bridge connected to a heat sink, and a first bridge connected to the first bridge and a second bridge connected in series to form a half bridge. Of the second switching element adjacent to the first and second electrode terminal faces of the first switching element and the first electrode terminal face of the first switching element.
A bottom insulator, an AC conductor, and an internal insulator are sequentially laminated on the electrode terminal surface, and a first flexible insulator and a P-side conductor are provided on a portion on the first switching element side in a surface of the internal insulator. Are sequentially laminated, a second flexible insulator and an N-side conductor are sequentially laminated on a portion on the second switching element side in the surface of the internal insulator, and the first flexible insulator; Penetrating through the internal insulator, the AC conductor and the bottom insulator thereunder and contact with the first electrode terminal surface of the first switching element;
One end of the P-side conductor is connected to a first electrode terminal of the first switching element via a conductor spacer insulated from the AC conductor, and a portion of the AC conductor on one end side The first convex portion provided on the first switching element is in contact with the second electrode terminal surface of the first switching element through the bottom insulator thereunder, and is provided at the other end of the AC conductor. The second protrusion penetrates the bottom insulator below it and is in contact with the first electrode terminal surface of the second switching element, and one end of the N-side conductor is an end face of the internal insulator. The N-side conductor extends to the second electrode terminal surface of the second switching element over the N-side conductor conductive spacer in contact with the second electrode terminal surface of the second switching element. Is connected to the second switching element. And connected between the P-side conductor and the N-side conductor in a direction perpendicular to the first and second electrode terminal surfaces of the first switching element. One end of the first flexible insulator and a direction perpendicular to the first and second electrode terminal surfaces of the second switching element and parallel to the one end of the first flexible insulator. A semiconductor stack characterized by being insulated by one end of the second flexible insulator extending. 2. The semiconductor stack according to claim 1, wherein a peripheral end of the bottom insulator is formed as a side wall having an L-shaped cross section, and the bottom insulation surrounded by the side wall is provided. A semiconductor stack, wherein the AC conductor is mounted on a surface of a body. 3. The semiconductor stack according to claim 1, wherein a rib that fits into a groove between the first and second electrode terminal surfaces of the first switching element is formed on the bottom insulator. A semiconductor stack. 4. The semiconductor stack according to claim 1, wherein the surface of the internal insulator is located above a groove between the first and second electrode terminal surfaces of the first switching element. above,
An upwardly projecting rib is formed integrally with the internal insulator, and the first flexible insulator and the P-side conductor are provided on the surface of the internal insulator inside the rib of the internal insulator. A semiconductor stack characterized by being sequentially stacked on top. 5. The semiconductor stack according to claim 1, wherein the other end of the second flexible insulator on the side of the second electrode terminal of the second switching element is connected to the second flexible element. The second switching element is fitted in a groove between the first and second electrode terminal faces while being separated from the one end of the N-side conductor beyond the end face of the internal insulator. The semiconductor stack. 6. The semiconductor stack according to claim 1, wherein at least the bottom insulator, the AC conductor, and the internal insulator are integrally formed. Semiconductor stack. 7. The semiconductor stack according to claim 1, wherein said one end of said AC conductor is:
The first switching element is bent in a direction perpendicular to the first and second electrode terminal surfaces to form an AC terminal, and the P-side conductor and the N-side conductor are each formed of the first switching element. The one end of the first flexible insulator and the second end are connected to each other from a substantially central portion between the first electrode terminal surface and the first electrode terminal surface of the second switching element.
Vertically bent so as to be parallel to each other via the one end of the flexible insulator, and further, the one end of the first flexible insulator and the one end of the second flexible insulator The other end of the P-side conductor and the other end of the N-side conductor are connected to P and N terminals, respectively, so that the cross-sectional shape becomes a U-shape apart from the portion. A semiconductor stack, which is formed.