阅读说明：本技术 半导体模块 (Semiconductor module ) 是由 竹内谦介 船越政行 长尾崇志 于 2018-08-20 设计创作，主要内容包括：本发明的半导体模块(1)包括：半导体开关元件(T1-T4)；多个基部(11),在至少任一个上安装有半导体开关元件(T1-T4)；模塑树脂(10),密封半导体开关元件(T1-T4)和多个基部(11)；多个端子(C1-C6、B1、B2、G1、G2、M1、M2),与多个基部(11)中的每一个一体形成,并且设置为从模塑树脂(10)的外周侧面突出；凹部(12)或凸部(13),在多个端子(C1-C6、B1、B2、G1、G2、M1、M2)间的模塑树脂(10)的外周(9)侧面的一部分中,具有确保多个端子(C1-C6、B1、B2、G1、G2、M1、M2)间的爬电距离的深度或高度,并且形成为横穿多个端子(C1-C6、B1、B2、G1、G2、M1、M2)间的相对部分。(A semiconductor module (1) of the present invention includes: a semiconductor switching element (T1-T4); a plurality of base sections (11) on which semiconductor switching elements (T1-T4) are mounted; a molding resin (10) that seals the semiconductor switching elements (T1-T4) and the plurality of bases (11); a plurality of terminals (C1-C6, B1, B2, G1, G2, M1, M2) formed integrally with each of the plurality of bases (11) and provided to protrude from an outer peripheral side surface of the molded resin (10); the recessed part (12) or the raised part (13) has a depth or a height that ensures a creepage distance between the plurality of terminals (C1-C6, B1, B2, G1, G2, M1, M2) in a part of the side surface of the outer periphery (9) of the molding resin (10) between the plurality of terminals (C1-C6, B1, B2, G1, G2, M1, M2), and is formed so as to cross the opposing part between the plurality of terminals (C1-C6, B1, B2, G1, G2, M1, M2).)

1. A semiconductor module, comprising:

a semiconductor switching element;

a plurality of base portions on at least one of which the semiconductor switching element is mounted;

a molding resin that seals the semiconductor switching element and the plurality of base portions;

a plurality of terminals formed integrally with each of the plurality of bases and provided to protrude from an outer peripheral side surface of the mold resin; and

and a concave portion or a convex portion having a depth or a height that ensures a creepage distance between the plurality of terminals and formed across an opposing portion between the plurality of terminals at a part of an outer peripheral side surface of the mold resin between the plurality of terminals.

2. The semiconductor module of claim 1,

the concave portion or the convex portion is the same material as the molding resin with a gap without contacting the plurality of terminals with the concave portion or the convex portion.

3. The semiconductor module according to claim 1 or 2,

the convex portion is formed in a mountain shape in an extending direction of the terminal, and has a first portion facing a thickness direction of the terminal,

the height of the convex portion is formed to be gradually lower than the first portion as being away from the thickness direction of the terminal.

4. The semiconductor module according to claim 1 or 2,

the concave part is formed by cutting a semicircle from the peripheral side surface of the molding resin,

the depth of the recess is formed to become shallower as it is away from the thickness direction of the terminal.

5. The semiconductor module according to any one of claims 1 to 4,

the concave portion or the convex portion has an inclined surface.

6. The semiconductor module according to any one of claims 1 to 5,

the plurality of terminals are formed to be arranged in a zigzag shape from an outer peripheral surface of the mold resin,

the opposing portions between the plurality of terminals are regions sandwiched by a plurality of wires connecting portions around the plurality of terminals adjacent to each other at the shortest distance,

the concave portion or the convex portion is arranged to intercept the region.

Technical Field

The present application relates to a semiconductor module.

Background

Conventionally, in a package of a semiconductor module, as a countermeasure against leakage, a creepage distance between terminals is made long by forming a space between the terminals protruding from an outer periphery of the package into a concave-convex shape. For example, in a conventional IC package of a semiconductor module disclosed in patent document 1, a stepped shape having projections and depressions is formed over the entire side surface of the IC package, and external leads are led out from recesses and projections of the outer shape of the package in a zigzag arrangement, thereby extending a creepage distance between terminals.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. Hei 1-113346

Disclosure of Invention

Technical problem to be solved by the invention

However, the IC package of the semiconductor module disclosed in patent document 1 has the following problems: the outer shape of the package and the terminals are different between adjacent ones, and the mold of the package formed by resin molding is manufactured in a complicated shape, and the workability is complicated. Further, there is a problem that resin peeling occurs to impair reliability of the semiconductor module because the surface of the mold in contact with the resin is wide when the mold is released from the mold.

The present application discloses a technique for solving the above-described problems, and an object thereof is to provide a semiconductor module in which a creepage distance between terminals is ensured, and workability of a mold resin is simplified and reliability is improved.

Means for solving the problems

The semiconductor module disclosed in the present application includes: a semiconductor switching element; a plurality of base portions, at least any one of which is mounted with the semiconductor switching element; a molding resin that seals the semiconductor switching element and the plurality of base portions; a plurality of terminals formed integrally with each of the plurality of bases and provided to protrude from an outer peripheral side surface of the mold resin; and a concave portion or a convex portion having a depth or a height that ensures a creepage distance between the plurality of terminals in a part of an outer peripheral side surface of the mold resin between the plurality of terminals, and formed to cross an opposing portion between the plurality of terminals.

Effects of the invention

According to the semiconductor module disclosed in the present application, a semiconductor module in which a creepage distance between terminals is ensured, and workability of a mold resin is simplified and reliability is improved can be obtained.

Drawings

Fig. 1 is a circuit diagram illustrating a semiconductor module according to embodiment 1.

Fig. 2A is a plan view showing an internal structure of the semiconductor module according to embodiment 1.

Fig. 2B is a side view showing the semiconductor module according to embodiment 1.

Fig. 3 is a partial detailed view showing a semiconductor module according to embodiment 1.

Fig. 4 is a partial detailed view showing a semiconductor module according to embodiment 1.

Fig. 5A is a partial plan view showing the semiconductor module according to embodiment 2.

Fig. 5B is a partial side view showing the semiconductor module according to embodiment 2.

Detailed Description

Next, a semiconductor module according to embodiment 1 will be described with reference to the drawings.

In the drawings, the same or corresponding portions are denoted by the same reference numerals.

Embodiment 1.

Fig. 1 is a circuit diagram illustrating a semiconductor module according to embodiment 1. The semiconductor module 1 incorporates at least one of a plurality of semiconductor switching elements T1-T4. Fig. 1 shows an H-bridge circuit for driving a motor 2, and a semiconductor module 1 includes the motor 2, a positive (+) power supply 3, and a ground 4. In FIG. 1, the double circle marks represent terminals C1-C6, B1, B2, G1, G2, M1, M2. The semiconductor switching elements T1 to T4 are, for example, Field Effect Transistors (FETs). As shown in fig. 1, in the semiconductor module 1, a bridge circuit is formed by 4 FETs, and the motor 2 is connected to the small-signal terminals C5 and C6 and the large-current terminals M1 and M2, which are intermediate connection positions of the upper and lower arms.

The small-signal terminals C1, C2, C3, and C4 are control signal terminals for driving the gate of the FET, and the small-signal terminals C5 and C6 are voltage monitoring terminals of the motor 2. The terminals B1 and B2 for large current are connected to the positive (+) power supply 3, and the terminals G1 and G2 for large current are connected to the ground 4. The output terminals to the motor 2 are a terminal M1 for large current and a terminal M2.

Fig. 2A is a plan view showing an internal structure of the semiconductor module according to embodiment 1, and the circuit structure shown in fig. 1 is formed as the semiconductor module 1. Fig. 2A is a perspective view of the semiconductor module 1, and the outline of the molding resin 10 is shown by a one-dot chain line. For example, the plate-shaped base 11 of copper or copper alloy is divided into a plurality of patterns. The terminals C1-C6, B1, B2, G1, G2, M1, and M2 are formed integrally with the plurality of base portions 11, respectively, and the semiconductor switching elements T1-T4 are mounted on the base portions 11. Terminals G1, B1, M1, M2, B2, and G2 for large current and terminals C2, C6, C1, C3, C5, and C4 for small signal, which are provided to extend and protrude from the base 11, are formed on the outer peripheral 9 side surface of the mold resin 10 of the semiconductor module 1. As shown in fig. 2A, terminals G1, B1, M1, M2, B2, and G2 for large current are arranged on the lower side in the drawing, and terminals C2, C6, C1, C3, C5, and C4 for small signal are arranged in this order on the upper side in the drawing.

As shown in fig. 1, since the FETs are connected in series with the upper and lower arms in the H-bridge circuit and they are formed in pairs, the arrangement in fig. 2A is also the same in the left-right direction, i.e., the mirror image arrangement. Therefore, only one of the arrangement and the connection will be described.

As shown in fig. 2A, the base 11 of the copper plate extends from the terminal B1 for large current into the semiconductor module 1, and a FET as a semiconductor switching element T1 is mounted. A gate (not shown) of an FET as the semiconductor switching element T1 is connected to the terminal C1 for small signal through a wire J3 by wire bonding. The base 11 of the copper plate is directly connected to a drain (not shown) of an FET as the semiconductor switching element T1, and a source (not shown) is electrically wired by a jumper wire J1. The jumper wire J1 is also formed in a copper plate shape in the same manner as the base portion 11 of the copper plate, and not only a large current flows but also excellent thermal conductivity.

One of the jumper wires J1 (lower side in the figure) is connected to the other base 11, and is connected to a terminal M1 for large current, which is an output terminal for outputting to the motor 2. The other (upper side in the figure) is connected to the base 11 of the FET of the semiconductor switching element T2 as the lower arm. The FET as the semiconductor switching element T2 is also similar to the FET as the semiconductor switching element T1 in that the gate is connected to the terminal C2 for small signals by a wire J3 by wire bonding, and the source is connected to the terminal G1 for large current as a ground terminal via a jumper J2.

As described above, in the semiconductor module 1 according to embodiment 1, the semiconductor switching elements T1, T2, T3, T4, the base 11, the jumper wires J1, J2, and the like are arranged and connected, and then the entire structure is covered with the one-dot chain line molding resin 10 and sealed.

In the semiconductor module 1, the semiconductor switching elements T1 to T4 are driven to be turned on and off, and are controlled by a large current. Specifically, the terminals G1, B1, M1, M2, B2, and G2 for large current are energized at a maximum of about 100A. The terminals C1 to C6 for small signals are controlled by a signal of a small current, and are energized to a current of several mA or less.

The terminals C1 to C6, B1, B2, G1, G2, M1, and M2 are arranged in proximity to each other to reduce the size of the semiconductor module 1 as a whole. Further, there is a possibility that electric leakage may occur due to an environment in which the semiconductor module 1 as a device is installed, or a material, paint, or the like of the mold resin 10, and the securing of the insulation may affect not only the normal driving of the semiconductor module 1 as a device but also the reliability of the entire device including the semiconductor module 1, for example, a power conversion device.

Therefore, in the semiconductor module 1 according to embodiment 1, it is necessary to secure a creepage distance, but if the distance is set to be excessively large, miniaturization of the device is not achieved. The creepage distance is generally defined according to the material, the degree of fouling, and the like, but the operating voltage is particularly important, and for example, when the device is mounted on a vehicle, the voltage is generally 14V, and therefore, the creepage distance may be about 1mm because of a low voltage. However, since the voltage is high when the voltage is about 350V in the electric vehicle, the creepage distance needs to be about 3mm when the operating voltage is also 350V.

In addition, the creepage distance is the shortest distance in which the terminals face each other along the molded resin 10 as an insulating resin, and therefore, the relative position with the adjacent terminal, the thickness and width of the terminal itself, and the distance between the sides of the terminal must also be considered. According to the semiconductor module 1 of embodiment 1, the concave portion 12 or the convex portion 13 is provided in a part of the outer periphery 9 of the semiconductor module 1 between the terminals. Thus, the shortest distance between the terminals is extended by the uneven surface.

As shown in fig. 2A, small-signal terminals C1, C6, and C2 are provided on the outer periphery 9 of the upper mold resin 10 in the drawing, and a recess 12 is provided on the outer periphery 9 between the small-signal terminals C1, C6, and C2. On the other hand, terminals M1, B1, and G1 for large current are provided on the outer periphery 9 of the lower mold resin 10 in the figure, and a convex portion 13 is provided on the outer periphery 9 between the terminals M1, B1, and G1 for large current. As shown in fig. 2A, in the case where the concave portion 12 and the convex portion 13 are not formed, the shortest distance between the terminals becomes the outer circumference 9 indicated by the one-dot chain line, but by providing the concave portion 12 and the convex portion 13, the distance along the outer circumference 9 can be arbitrarily obtained by the depth of the concave portion 12 or the height of the convex portion 13. Further, there is a gap so that the plurality of terminals C1, C6, C2 do not meet the concave portion 12 or the plurality of terminals M1, B1, G1 do not meet the convex portion 13.

In addition, since the space 14a between the small-signal terminal C1 and the terminal C3 and the space 14b between the large-current terminals M1 and M2 are long and wide, it is not necessary to provide the concave portion 12 or the convex portion 13 in order to secure a creepage distance. Fig. 2B is a side view showing the semiconductor module according to embodiment 1. As shown in fig. 2B, the shape of the convex portion 13 is a mountain shape (including a trapezoid) formed in the extending direction of the terminal G2. In the semiconductor module 1, the convex portion 13 may not be formed over the side surface of the outer periphery 9 of the mold resin 10. Further, the convex portion 13 may be provided between the small-signal terminals C1 to C6, and the concave portion 12 may be provided between the large-current terminals G1, B1, M1, M2, B2, and G2, or either the concave portion 12 or the convex portion 13 may be provided.

Next, the concave-convex portion will be described in further detail with reference to fig. 3 and 4. Fig. 3 is a partial detailed view showing a semiconductor module according to embodiment 1. Fig. 3 is a cross-sectional view of the semiconductor module 1 shown in fig. 2A, as viewed from the terminals C6-B1, C2-G1, and the one-dot chain line indicates the outer periphery 9 of the semiconductor module 1.

In the semiconductor module 1 according to embodiment 1, the recess 12 provided in the vicinity of the small-signal terminal C2 is hollowed out from the outer periphery 9 in a substantially semicircular shape. On the other hand, the convex portion 13 is formed in a trapezoidal shape so as to protrude in the extending direction of the terminal G1. Since the creepage distance is the shortest distance between the end portions of the terminals, in the semiconductor module 1 of embodiment 1, the portion of the convex portion 13 facing the thickness direction t of the terminal G1 for large current is highest, and gradually decreases as it is farther from the thickness direction t of the terminal. That is, the projection height of the projection 13 can be varied according to the distance of the facing portion 8 between the terminals.

The protruding portion 13 is disposed so as to cross the facing portion 8 between the terminals, and the height thereof is made variable so that a creepage distance can be ensured. Similarly, in the concave portion 12, as shown by a broken line 12a, the thickness direction of the terminal C2, that is, the opposing portion 8 of the terminals is deepest, and the concave portion 12 can be made shallower as it goes away from the thickness direction t. Further, by providing the concave portion 12 or the convex portion 13, the spatial distance of the facing portions 8 of the terminals can be extended naturally, and therefore, not only the leakage current but also the discharge from the terminals can be prevented effectively.

Fig. 4 is a partial detailed view showing the semiconductor module according to embodiment 1, and is a perspective enlarged view partially showing the convex portion 13 in an enlarged manner. The convex portion 13 is disposed on the outer peripheral 9 side surface (wall surface) of the mold resin 10 between the terminal G1 for large current and the terminal B1 for large current in the semiconductor module 1. Here, when observing the creepage distance between the terminal G1 for large current and the terminal B1 for large current, the length of the line L1 linearly drawn from 1 corner where the terminal G1 for large current and the terminal B1 for large current face along the surface of the convex portion 13 is longer than the case where the convex portion 13 is not present. Since this length can be regarded as a creepage distance, the length can be changed to a desired distance by changing the height of the projection 13.

In addition, the line L2 is drawn out at a lower point of the convex portion 13, while the corner of the terminal at the departure and arrival points is the same as the line L1. The line length of the line L2 must be such that a desired creepage distance is ensured, and when the height gradually decreases from the top of the projection 13, the inclined surface 7 needs to be determined carefully. That is, the shortest distance between the terminals is not limited to a straight line, and the periphery of the concave portion 12 or the convex portion 13 and the outer periphery 9 of the molding resin 10 as the package should also be considered.

The recess 12 may be formed to have a smooth inclined surface 7 from the inside toward the outer periphery 9. By providing the inclined surface 7 in the concave portion 12 or the convex portion 13, there is also an advantage that: the mold release for molding the molding resin 10 of the entire semiconductor module 1 becomes easy.

In the semiconductor module 1 according to embodiment 1, the significant difference in the creepage distance is small regardless of whether the concave portion 12 or the convex portion 13 is provided, but it is also possible to select which one is provided according to other conditions. For example, when the base 11 or the like is provided at a position close to the outer periphery 9 of the mold resin 10, there is no room for providing the recess 12, and thus the semiconductor module 1 having high reliability can be obtained by providing the recess 13. In addition, when the creepage distance needs to be extended further, the concave portion 12 and the convex portion 13 can be provided in combination.

As described above, according to the semiconductor module 1 of embodiment 1, the concave portion 12 or the convex portion 13 is included in a part of the side surface of the outer periphery 9 of the mold resin 10 between the plurality of terminals C1-C6, B1, B2, G1, G2, M1, and M2, and the concave portion 12 or the convex portion 13 has a depth or a height that ensures the creepage distance between the plurality of terminals C1-C6, B1, B2, G1, G2, M1, and M2 and is formed to cross the opposing portion 8 between the plurality of terminals C1-C6, B1, B2, G1, G2, M1, and M2, whereby the reliability of the semiconductor module 1 can be improved. The convex portion 13 may not be formed integrally with the mold resin 10 of the semiconductor module 1, but if it is formed integrally, it can be formed in the same step as the molding, and thus, the manufacturing process can be simplified.

Further, according to the semiconductor module 1 of embodiment 1, the space distance between the terminals can be extended while securing the creepage distance to improve the reliability. In the semiconductor module 1, since the terminals are formed in the concave-convex shape in a part of the outer periphery 9 of the mold resin 10, the arrangement and the shape of the terminals themselves are not affected, and thus the workability of the semiconductor module 1, which is a manufacturing apparatus, is not lowered.

Embodiment 2.

Fig. 5A is a partial plan view of the semiconductor module according to embodiment 2, and fig. 5B is a partial side view of the semiconductor module according to embodiment 2. Fig. 5A and 5B show a semiconductor module 1a having a circuit configuration similar to that of embodiment 1, but other configurations. Here, the securing of the creepage distance between the plurality of terminals C10-C13 will be described with reference to fig. 5A and 5B.

As shown in fig. 5B, in the semiconductor module 1a according to embodiment 2, the plurality of terminals C10-C13 are arranged in a shape of a bird (zigzag) from the outer peripheral side surface 9 of the mold resin 10. In addition, not only the thickness of each terminal C10-C13, but also the width direction of each terminal C10-C13 also affects the opposing portion 8 of each terminal C10-C13. In the arrangement of the plurality of terminals C10 to C13, the creepage distance is the shortest distance of the opposing portion 8 between the plurality of terminals C10 to C13, and therefore, becomes a straight line from each side of the terminals C10 to C13. In fig. 5A and 5B, the broken line 18 is a plurality of lines connecting the corners of the terminal C10 from the corner of the terminal C12, and the opposing line 17 shown by the other broken lines corresponds to the opposing portion 8 of the terminal C10 and the terminal C12, and therefore, it is necessary to provide a concave-convex portion so as to cross between the regions. That is, the facing portion 8 between the plurality of terminals C10-C13 in embodiment 2 is a region of an area portion surrounded by a plurality of lines connecting arbitrary portions around the adjacent plurality of terminals C10-C13 at the shortest distance.

In fig. 5A and 5B, description will be made using an example in which the convex portion 15 is formed in the facing portion 8 between the plurality of terminals C10-C13. As shown in fig. 5B, for example, the facing portion 8 of the terminal C10 and the terminal C12 is a region of an area portion sandwiched and surrounded by the facing line 17 indicated by another broken line, and is indicated by oblique lines. The opposing portion 8 of the terminal C10 and the terminal C13 is also a region of an area portion sandwiched and surrounded by the opposing line 17 indicated by another broken line. As shown in fig. 5A and 5B, in a semiconductor module 1a of embodiment 2, a convex portion 15 is provided in a facing portion 8 surrounded by a facing line 17 indicated by another broken line. Therefore, in the semiconductor module 1a according to embodiment 2, the convex portion 15 has a laterally long shape. Thus, in the semiconductor module 1a according to embodiment 2, the convex portions 15 are provided between the upper and lower terminals.

The convex portion 16 is also provided between terminals adjacent in the lateral direction, for example, between the terminal C10 and the terminal C11, and between the terminal C12 and the terminal C13.

As described above, according to the semiconductor module 1a according to embodiment 2, the protruding portion 15 or the protruding portion 16 is provided in the facing portion 8 between the terminals, thereby ensuring the creepage distance. Since the convex portion 15 or the convex portion 16 is provided so as to cross (block) the opposing portion 8, in particular, the convex portion 15 may block the opposing line 17 at a horizontal position in the drawing, and thus, the arrangement in the left-right direction has a degree of freedom. Further, since the shortest distance between the terminals of the convex portion 16 is longer than that of the convex portion 15, the height of the convex portion 16 can be formed lower than that of the convex portion 15.

In the semiconductor module 1a according to embodiment 2, the convex portion 15 or the convex portion 16 may not be formed integrally with the mold resin 10 of the semiconductor module 1a, but if formed integrally, they can be formed by the same step in molding, and thus, there is an effect that the manufacturing process can be simplified. In the semiconductor module 1a according to embodiment 2, a recess (not shown) may be provided so as to block the facing portion 8 between the terminals C10-C13. In the semiconductor module 1a according to embodiment 2, the uneven portion can be formed into a simple structure by unifying the shape of the concave portion or the convex portion as much as possible.

In embodiment 2, the opposing portion 8 between the plurality of terminals C10-C13 is defined as a region of an area portion sandwiched and surrounded by a plurality of lines connecting arbitrary portions around the adjacent plurality of terminals C10-C13 at the shortest distance, but in the semiconductor module 1 of embodiment 1, the opposing portion 8 between the terminal G1 and the terminal B1 shown in fig. 4, for example, may be a region of an area portion sandwiched and surrounded by a plurality of lines connecting arbitrary portions around the adjacent plurality of terminals, that is, the terminal G1 and the terminal B1, at the shortest distance, of course.

Although various exemplary embodiments and examples have been described in the present application, the various features, aspects, and functions described in 1 or more embodiments are not limited to be applied to a specific embodiment, and may be applied to the embodiments alone or in various combinations.

Therefore, it is considered that numerous modifications not illustrated are also included in the technical scope disclosed in the present specification. For example, the case where at least 1 component is modified, added, or omitted, and the case where at least 1 component is extracted and combined with the components of the other embodiments are also included.

Description of the reference symbols

1. 1a semiconductor module; 2, a motor; 3, a power supply; 4, grounding; 7, inclined plane; 8 opposite parts; 9 outer periphery; 10 a molding resin; 11 a base; 12a recess; 12a in dashed lines; 13. 15, 16 convex parts; 17 relative to the line; 18 in dashed lines; c1, C2, C3, C4, C5, C6, C10, C11, C12, C13, B1, B2, G1, G2, M1, M2 terminals; t1, T2, T3, T4 semiconductor switching elements.