WO2025084080A1 - Semiconductor device, production method for same, and power conversion device - Google Patents

Abstract

The purpose of the present disclosure is to provide a structure for a semiconductor device that has a principal terminal that improves performance and yield. A case accommodation space (S5) that is enclosed by a case (5) of a power module (1) accommodates solder (30, 31), a ceramic substrate (10), a plurality of semiconductor elements (20), wire (41–43), and a sealing resin (7) that is provided on an installation surface (15s) of a fin base (15). The entirety of the solder (30, 31), the plurality of semiconductor elements (20), and the wire (41–43) and a portion of a metal block (60) are covered by the sealing resin (7), but an upper surface and a portion of an upper part of a side surface of the metal block (60) are not covered by the sealing resin (7) and are exposed. A principal terminal (62) is fixed onto the upper surface of the metal block (60) with a screw (61).

Description

Semiconductor device, its manufacturing method, and power conversion device

This disclosure relates to a semiconductor device having a main terminal for transmitting external signals, such as a power module.

Power modules are a typical example of semiconductor devices that have a main terminal for transmitting external signals. Power modules are becoming more common in all kinds of products, from industrial equipment to home appliances and information terminals, and they are required to be small and lightweight, with high productivity and ease of assembly. Power modules are used in a wide range of situations, from power generation and transmission to efficient energy utilization and regeneration.

Power modules are likely to become mainstream in the future due to their high operating temperature and excellent efficiency. In addition, power modules are also required to be packaged in a form that can be applied to wide band gap semiconductors such as SiC.

For example, Patent Document 1 discloses a component mounting board on which electronic components such as power transistors are mounted. The above-mentioned electronic components become the constituent elements of a power module.

JP 2016-4644 A

As mentioned above, as environmental issues grow, power modules are becoming more common in all aspects of electrical energy generation, transmission, and regeneration. Power modules used in electric vehicles, home appliances, and other applications require particularly high productivity and ease of assembly. They also need to be small and lightweight to reduce energy consumption during manufacturing.

Because power modules handle large currents and high voltages, electrical connections to the equipment are often made using bus bars made of metal plates that serve as the main terminals, or copper twisted wire. Several fixing methods, such as screwing, welding, and soldering, are used to fasten the bus bars, which serve as the main terminals and carry the power semiconductor elements, to the insulating substrate.

The component mounting board disclosed in Patent Document 1 shows a method of placing a terminal block with a screw hole on the board and tightening the terminal block to the main terminal of a wiring cable or the like with a screw.

When attempting to apply the method disclosed in Patent Document 1 to a power module, there was concern that the ceramic substrates commonly used as insulating substrates would be fragile and would be damaged by the torque applied when tightening the screws. In addition, when attempting to join the bus bars that serve as the main terminals to the terminal block by resistance welding or laser welding, there was concern that spatter would fly from a position higher than the surface of the insulating substrate, deteriorating the insulation of the completed power module.

　Conventional semiconductor devices, such as power modules, are constructed as described above, and have problems with low device yield and performance.

This disclosure has been made to solve the above problems, and aims to provide a semiconductor device with a main terminal that improves yield and performance.

The semiconductor device according to the present disclosure is a semiconductor device having a main terminal for transmitting an external signal, comprising: a substrate having first and second main surfaces; a semiconductor element provided on the first main surface of the substrate; a metal block provided on a block mounting member which is at least one of the substrate and the semiconductor element; the block mounting member and the metal block are joined via a block bonding material, the metal block has a main terminal mounting region, the main terminal is fixed to the metal block at the main terminal mounting region, and the semiconductor device further comprises a sealing resin provided on the first main surface of the substrate, covering at least the block mounting member and the block bonding material.

The semiconductor device disclosed herein can reduce damage to the metal block when attaching the main terminal to the metal block in the main terminal attachment area by using the sealing resin that covers at least the block mounting member and the block bonding material.

In addition, in the semiconductor device disclosed herein, since a sealing resin is provided on the first main surface of the substrate, when the main terminal is fixed to the metal block in the main terminal mounting area, the first main surface of the substrate is protected by the sealing resin, and the performance of the substrate is not deteriorated.

In this way, the semiconductor device disclosed herein has a structure that does not adversely affect the substrate during the manufacturing stage, which can improve the yield and performance of the device.

The objects, features, aspects, and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings.

FIG. 1 is an explanatory diagram illustrating a planar structure of a power module according to a first embodiment of the present invention; FIG. 2 is an explanatory diagram showing a schematic cross-sectional structure taken along line AA in FIG. FIG. 2 is a perspective view showing the overall structure of the power module shown in FIG. 1 . FIG. 1 is an explanatory diagram (part 1) showing a schematic cross-sectional structure of a power module according to a basic aspect of the first embodiment during a manufacturing process. FIG. 2 is an explanatory diagram (part 2) showing a schematic cross-sectional structure of the power module according to the basic aspect of the first embodiment during the manufacturing process. FIG. 11 is an explanatory diagram (part 3) showing a schematic cross-sectional structure of the power module according to the basic aspect of the first embodiment during the manufacturing process. FIG. 4 is an explanatory diagram (part 4) showing a schematic cross-sectional structure of the power module according to the basic aspect of the first embodiment during the manufacturing process. FIG. 5 is an explanatory diagram (part 5) showing a schematic cross-sectional structure of the power module during the manufacturing process according to the first embodiment; FIG. 2 is an explanatory diagram illustrating a cross-sectional structure of a power module according to a second aspect of the first embodiment. FIG. 11 is an explanatory diagram illustrating a cross-sectional structure of a power module according to a third aspect of the first embodiment. FIG. 11 is an explanatory diagram illustrating a planar structure of a power module according to a second embodiment of the present invention; 12 is an explanatory diagram showing a schematic cross-sectional structure taken along the line BB in FIG. 11. FIG. 11 is an explanatory diagram (part 1) showing a schematic cross-sectional structure of a power module according to a basic aspect of the second embodiment during a manufacturing process. FIG. 13 is an explanatory diagram (part 2) illustrating a cross-sectional structure during a manufacturing process of a power module according to a basic aspect of the second embodiment. FIG. 11 is an explanatory diagram (part 3) showing a schematic cross-sectional structure of a power module according to a basic aspect of the second embodiment during a manufacturing process. FIG. 4 is an explanatory diagram (part 4) showing a schematic cross-sectional structure of a power module according to a basic aspect of the second embodiment during a manufacturing process. FIG. 5 is an explanatory diagram (part 5) illustrating a cross-sectional structure during a manufacturing process of a power module according to a basic aspect of the second embodiment. FIG. 11 is an explanatory diagram illustrating a cross-sectional structure of a power module according to a second aspect of the second embodiment. FIG. 11 is an explanatory diagram illustrating a planar structure of a power module according to a third embodiment. 20 is an explanatory diagram showing a schematic cross-sectional structure taken along the line CC in FIG. 19. FIG. 11 is an explanatory diagram (part 1) illustrating a schematic cross-sectional structure during a manufacturing process of a power module according to embodiment 3. FIG. 13 is an explanatory diagram (part 2) illustrating a cross-sectional structure during a manufacturing process of the power module according to the third embodiment. FIG. 13 is an explanatory diagram (part 3) illustrating a schematic cross-sectional structure during the manufacturing process of the power module according to the third embodiment. FIG. 11 is an explanatory diagram (part 4) illustrating a cross-sectional structure during a manufacturing process of the power module according to the third embodiment. FIG. 5 is an explanatory diagram (part 5) illustrating a cross-sectional structure during the manufacturing process of the power module according to the third embodiment. FIG. 11 is a block diagram showing a configuration of a power conversion system to which a power conversion device according to a fourth embodiment is applied.

<First embodiment>
(Basic form)
Hereinafter, a power module 1 serving as a semiconductor device according to a basic aspect of the first embodiment of the present disclosure will be described.

FIG. 1 is an explanatory diagram showing a schematic planar structure of the power module 1. FIG. 2 is an explanatory diagram showing a schematic cross-sectional structure taken along the line A-A in FIG. 1. FIG. 3 is a perspective view showing the overall structure of the power module 1. An XYZ orthogonal coordinate system is shown in each of FIGS. 1 to 3. Note that the sealing resin 7 is not shown in FIG. 3.

As shown in these figures, a fin base 15, which is a heat dissipation fin, is provided on the bottom layer of the power module 1. The fin base 15 has a base portion 15m and a number of pins 15p. The planar shape of the base portion 15m is, for example, 100 mm x 100 mm, and the thickness of the base portion 15m is set to, for example, 3 mm. Possible materials for the base portion 15m include copper, nickel plating, etc.

The upper surface of the base portion 15m on the +Z direction side becomes the mounting surface 15s. As described above, the planar shape of the mounting surface 15s is, for example, 100 mm x 100 mm. The case 5 and ceramic substrate 10, which will be described later, are provided on the mounting surface 15s. On the lower surface on the -Z direction side of the base portion 15m, multiple pins 15p are provided in a matrix shape at equal intervals. The diameter of each of the multiple pins 15p in the XY plane is set to, for example, 1.5 mm, and the length along the Z direction is set to, for example, 8 mm.

The case 5 is attached to the mounting surface 15s of the fin base 15. The planar shape of the case 5 in the XY plane is set to, for example, 92 mm x 80 mm, and the height of the case 5 in the Z direction is approximately 10 mm. The case 5 is thought to be made of PPS resin.

In this way, in the power module 1, the planar shape (100 mm x 100 mm) of the mounting surface 15s of the fin base 15 has dimensional characteristics that are wider than the planar shape (92 mm x 80 mm) of the case 5.

The case 5, which is the storage space forming member, has a hollow structure with a case storage space S5 inside, and within the case storage space S5, the ceramic substrate 10, which serves as an insulating substrate, is joined by solder 30 onto the mounting surface 15s of the fin base 15. The depth of the case storage space S5 is approximately 10 mm, reflecting the formation height of the case 5. The case storage space S5 is the element storage space formed by the storage space forming member.

The ceramic substrate 10, which is an insulating substrate, has a silicon nitride substrate 11 that serves as an insulating base material, an upper conductor layer 12 provided on the upper surface of the silicon nitride substrate 11 on the +Z direction side, and a lower conductor layer 13 provided on the lower surface of the ceramic substrate 10 on the -Z direction side. The surface of the upper conductor layer 12 becomes the first main surface of the substrate, and the surface of the lower conductor layer 13 becomes the second main surface of the substrate.

The planar shape of the silicon nitride substrate 11 in the XY plane is, for example, 70 mm x 58 mm, and the film thickness of the silicon nitride substrate 11, i.e., the height along the Z direction, is set to, for example, 0.32 mm.

Hereinafter, the planar shape in the XY plane may be referred to simply as the "planar shape," and the height in the Z direction may be referred to simply as the "height."

The thickness of each of the upper conductor layer 12 and the lower conductor layer 13 is set to, for example, 0.8 mm, and the constituent material is, for example, copper.

A plurality of semiconductor elements 20 are mounted on the surface of the upper conductor layer 12 of the ceramic substrate 10 via solder 31. That is, the first main surface of the substrate and the plurality of semiconductor elements 20 are joined via the solder 31. As shown in FIG. 1, in the power module 1 which is the basic aspect of the first embodiment, four semiconductor elements 20 are shown as the plurality of semiconductor elements 20.

The solder 30 that serves as the substrate bonding material between the fin base 15 and the ceramic substrate 10, and the solder 31 that serves as the substrate bonding material between the ceramic substrate 10 and the semiconductor element 20, are composed of, for example, 96.5% tin, 3% silver, and 0.5% copper, and the melting points of the solder 30 and the solder 31 are set to, for example, 217°C.

The multiple semiconductor elements 20 may be diodes or IGBTs (Insulated Gate Bipolar Transistors). Diodes may be made of silicon, for example, and have a planar configuration of 10 mm x 8 mm, with a thickness (formation height) set to 0.2 mm, for example. IGBTs may be made of silicon, for example, and have a planar configuration of 10 mm x 10 mm, with a thickness set to 0.2 mm, for example.

The signal terminal 63 is fixed to the case 5 in such a manner that a portion of it is inserted into the case 5. The signal terminal 63 is made of, for example, copper, and its width in the Y direction is set to, for example, 1.5 mm, and its thickness is set to, for example, 0.6 mm.

The case 5 has an intermediate horizontal portion 5a and an outer frame standing portion 5b, and the signal terminal 63 has a bent shape consisting of a terminal horizontal portion 63a and a terminal standing portion 63b, with the terminal horizontal portion 63a inserted into the intermediate horizontal portion 5a and a part of the terminal standing portion 63b inserted into the outer frame standing portion 5b.

A portion of the upper surface of the terminal horizontal portion 63a of the signal terminal 63 is exposed from the intermediate horizontal portion 5a, and the upper surface of the exposed terminal horizontal portion 63a is electrically connected to the upper surface of the semiconductor element 20 by a wire 41. For example, an aluminum wire having a diameter of 0.15 mm is used as the wire 41. The signal terminal 63 and the wire 41 form a signal circuit.

Furthermore, wire 42 electrically connects the surface of upper conductor layer 12 to the surface of semiconductor element 20. Wire 43 electrically connects the surfaces of semiconductor elements 20, 20. Wires 42 and 43 are, for example, aluminum wires with a diameter of 0.4 mm.

The metal block 60 is fixed to the surface of the upper conductor layer 12 of the ceramic substrate 10 by solder 31. That is, a portion of the solder 31 is used as a block bonding material for fixing the metal block 60.

The metal block 60 is made of brass, for example, and has a rectangular shape with a planar configuration of 7 mm x 6 mm and a height of 5 mm. In other words, the metal block 60 has a rectangular prism shape. The metal block 60 has a screw hole region 60x that is provided from the center of the upper surface to the lower surface. The screw hole region 60x that penetrates the metal block 60 in this way along the height direction functions as a main terminal attachment region.

The thickness (5 mm) of the metal block 60 in the height direction along the Z direction is set to be sufficiently thick compared to the film thickness (0.8 mm) of the upper conductor layer 12.

In the power module 1, the ceramic substrate 10 functions as a block mounting member. That is, the ceramic substrate 10, which serves as the block mounting member, and the metal block 60 are joined via solder 31. The solder 31 between the ceramic substrate 10 and the metal block 60 functions as a joining material for the block.

The main terminal 62 is fixed to the top surface of the metal block 60 by a screw 61. The main terminal 62 has an opening 62o in the screw attachment portion 62a on the -X direction side. The main terminal 62 is made of copper, for example, and has a width in the Y direction set to 8 mm and a thickness set to 1 mm.

The end of the main terminal 62 on the +X side opposite the screw mounting portion 62a is provided to protrude from the case housing space S5 to the outside. Note that the main terminal 62 may be a bus bar or a terminal for an external wiring cable.

The screw 61 is made of brass, for example, and meets the standard for an "M4 pan head screw." The screw 61 has a head 61a and a threaded portion 61b, and the length of the threaded portion 61b is set to, for example, 5 mm. The main terminal 62 is fixed onto the top surface of the metal block 60 in an attachment manner in which the threaded portion 61b of the screw 61 is inserted into the opening 62o of the main terminal 62 and the threaded hole area 60x of the metal block 60.

In this way, the metal block 60 has an upper surface and a screw hole area 60x as a main terminal mounting area, and the main terminal 62 is fixed to the metal block 60 in the main terminal mounting area by the screw 61.

The metal block 60, the screw 61, and the main terminal 62 are components included in the main circuit of the power module 1.

In the case housing space S5 surrounded by the case 5, sealing resin 7 is provided to cover the solder 30 provided on the mounting surface 15s of the fin base 15, the ceramic substrate 10, the solder 31, the semiconductor elements 20, and the wires 41 to 43. The sealing resin 7 may be made of, for example, epoxy resin with silica filler dispersed therein.

The top surface and a portion of the upper side of the metal block 60 are not covered by the sealing resin 7 and are exposed. For example, the case storage space S5 is sealed with the sealing resin 7 to a depth of 8 mm, and the metal block 60 is exposed about 2 mm from the top surface.

In other words, an upper portion of the side of the metal block 60 is not covered by the sealing resin 7 and is exposed, and the exposed side of the metal block 60 includes a pair of exposed side surfaces 60s and 60s that are parallel to the Y direction and face each other in the X direction.

Since the pair of exposed side surfaces 60s and 60s are exposed from the sealing resin 7 by about 2 mm, the metal block 60 can be restrained by clamping the pair of exposed side surfaces 60s and 60s using an existing restraining tool.

The exposed width and exposed length of the exposed side surface 60s must be set to a length that allows the metal block 60 to be restrained using an existing restraining tool.

The power module 1 has a case housing space S5 in the case 5 as an element housing space that houses the ceramic substrate 10, the multiple semiconductor elements 20, and the metal block 60. The sealing resin 7 is provided in the case housing space S5.

The power module 1, which is the basic aspect of the first embodiment, is provided with sealing resin 7 covering the ceramic substrate 10 that serves as the block mounting member and the solder 31 that serves as the bonding material for the block. Therefore, the base portion of the metal block 60 is reinforced by the sealing resin 7.

Therefore, the sealing resin 7 can reduce damage to the metal block 60 when the main terminal 62 is attached to the main terminal attachment area using the screw 61. In the power module 1, the top surface of the metal block 60 and the screw hole area 60x form the main terminal attachment area.

In addition, in the power module 1, since the sealing resin 7 is provided on the surface of the upper conductor layer 12, which is the first main surface of the substrate, the surface of the upper conductor layer 12 is protected by the sealing resin 7 when the main terminal 62 is attached to the metal block 60 in the main terminal attachment region described above. Therefore, the performance of the ceramic substrate 10 is not deteriorated when the main terminal 62 is fixed to the metal block 60. For example, the insulating property can be considered as the performance of the ceramic substrate 10, which is an insulating substrate.

In this way, the power module 1, which is the basic aspect of the first embodiment, has a structure that does not adversely affect the ceramic substrate 10 during the manufacturing stage, thereby improving the yield and performance of the device.

The top surface of the metal block 60 in the power module 1 is exposed and not covered by the sealing resin 7, so that even after the device is completed, rework can be performed relatively easily to replace the main terminal 62 fixed on the top surface of the metal block 60 with a new main terminal. This allows for flexibility in the selection of the main terminal 62.

The power module 1 can be attached relatively easily by fixing the main terminal 62 to the top surface of the metal block 60 using screws 61.

The power module 1 has sealing resin 7 disposed in the case housing space S5, which is the element housing space of the case 5, which is the housing space forming member, and this allows the height of the sealing resin 7 to be adjusted relatively easily during manufacturing.

The power module 1 has a fin base 15, which serves as a heat dissipation fin, provided via solder 30 on the surface of the lower conductor layer 13 of the ceramic substrate 10, which forms the second main surface of the substrate. Therefore, heat generated during operation of the multiple semiconductor elements 20 can be effectively dissipated by a heat dissipation path that includes the ceramic substrate 10 and the fin base 15.

The case 5, which is the storage space forming member in the power module 1, is provided on the mounting surface 15s of the fin base 15, which serves as the heat dissipation fin, so that the case storage space S5, which serves as the element storage space, can be secured and provided with good stability.

The power module 1 has a case housing space S5 secured by a dedicated case 5, so multiple semiconductor elements 20 and metal blocks 60 can be stably housed within the case housing space S5, and the height of the sealing resin 7 can be adjusted with high precision during manufacturing.

(Production method of the basic embodiment)
4 to 8 are explanatory diagrams that show schematic cross-sectional structures of the power module 1 during the manufacturing process, which is a basic aspect of the first embodiment. An XYZ orthogonal coordinate system is depicted in each of Figs. 4 to 8. The manufacturing method of the power module 1 will be described below with reference to Figs. 4 to 8.

As shown in Figures 1 to 3, the power module 1 includes four semiconductor elements 20 and three metal blocks 60, but for ease of explanation, the following description will be based on the structure shown in Figures 4 to 8.

First, a ceramic substrate 10 is prepared as the substrate for the semiconductor device of the first embodiment. The ceramic substrate 10 has a silicon nitride substrate 11 which is an insulating substrate, an upper conductor layer 12 provided on the upper surface of the silicon nitride substrate 11, and a lower conductor layer 13 provided on the lower surface of the silicon nitride substrate 11. In the power module 1, the ceramic substrate 10 serves as a block mounting member.

Next, as shown in FIG. 4, the solder 31, two semiconductor elements 20, and one metal block 60 are positioned above the upper conductor layer 12 of the ceramic substrate 10, and solder bonding is performed using the solder 31 in a reflow furnace.

As a result, two semiconductor elements 20 and one metal block 60 are mounted on the surface of the upper conductor layer 12 of the ceramic substrate 10. That is, the metal block 60 is joined via the solder 31 to the first main surface of the ceramic substrate 10, which serves as the block mounting member.

Then, as shown in FIG. 5, the surface of the lower conductor layer 13 of the ceramic substrate 10 is joined to the mounting surface 15s of the fin base 15 via solder 30. In other words, the fin base 15, which is a heat dissipation fin, is fixed to the surface of the lower conductor layer 13 of the ceramic substrate 10.

Next, as shown in FIG. 6, the case 5 is glued and fixed onto the mounting surface 15s of the fin base 15. The case 5, which is a member forming the housing space, has a case housing space S5 that serves as the element housing space, and the case 5 is fixed onto the mounting surface 15s of the fin base 15 to house the solder 30 and the ceramic substrate 10 within the case housing space S5.

The signal terminal 63 is integrated with the case 5, with the terminal horizontal portion 63a provided within the intermediate horizontal portion 5a and a portion of the terminal standing portion 63b provided within the outer frame standing portion 5b. After being fixed to the fin base 15 of the case 5, the intermediate horizontal portion 5a is located above the upper surface conductor layer 12 and a portion of the surface of the terminal horizontal portion 63a is exposed.

After the case 5 is fixed to the fin base 15, wiring is performed using wires 41 to 43. That is, wire 41 electrically connects the surface of the terminal horizontal portion 63a to the semiconductor element 20, wire 42 electrically connects the semiconductor element 20 to the upper surface conductor layer 12, and wire 43 electrically connects the semiconductor elements 20, 20 together. After wiring the wires 41 to 43, a circuit is formed that includes the two semiconductor elements 20, wires 41 to 43, metal block 60, and signal terminal 63.

Next, as shown in FIG. 7, sealing resin 7 is injected into the case housing space S5 to the extent that the top surface and a portion of the upper side of the metal block 60 are exposed, and then heated and cured. As a result, the solder 30, ceramic substrate 10, semiconductor elements 20, and wires 41 to 43 are all covered with sealing resin 7 within the case housing space S5.

On the other hand, the top surface and a portion of the upper part of the side surface of the metal block 60 are not covered with the sealing resin 7 and are exposed. That is, the exposed side surface of the metal block 60 includes a pair of exposed side surfaces 60s and 60s that face each other in the X direction. The pair of exposed side surfaces 60s and 60s are both parallel to the YZ plane. Furthermore, no sealing resin 7 is provided in the screw hole region 60x.

Finally, as shown in FIG. 8, the screw hole area 60x of the metal block 60 and the opening 62o of the main terminal 62 are positioned so that they match in a plan view, and the metal block 60 and the main terminal 62 are connected and fixed using the screw 61.

In other words, the main terminal 62 is fixed to the top surface of the metal block 60 in an installation manner in which the threaded portion 61b of the screw 61 is inserted into the opening 62o of the main terminal 62 and the threaded hole region 60x of the metal block 60.

As shown in FIG. 8, the metal block 60 is sealed partway with the sealing resin 7, so when the main terminal 62 is attached to the top surface of the metal block 60 with the screw 61, the tightening torque of the screw 61 reduces damage to the solder 31, which serves as the block bonding material that bonds the metal block 60 to the top conductor layer 12. To maximize this effect, it is desirable to set the depth of the sealing resin 7 so that the sealing resin 7 is present up to 20% or more of the height of the metal block 60.

In addition, since the pair of exposed side surfaces 60s and 60s are exposed by about 2 mm from the sealing resin 7, the metal block 60 can be restrained by clamping the pair of exposed side surfaces 60s and 60s using an existing restraining tool.

Therefore, with the metal block 60 stably fixed, the threaded portion 61b of the screw 61 is inserted into the opening 62o of the main terminal 62 and the threaded hole area 60x of the metal block 60, and then the screw 61 is tightened with a predetermined torque, thereby fastening and fixing the main terminal 62 to the upper surface of the metal block 60.

In this way, the main terminal 62 can be fixed with the metal block 60 stably restrained by the pair of exposed side surfaces 60s and 60s, which further reduces damage to the solder 31, which is the joining material for the fixing block, when the main terminal 62 is fixed, and further reduces damage to the semiconductor element 20.

In the power module 1, copper is used as the material for the fin base 15, but the same effect can be obtained by using aluminum partially nickel-plated as the constituent material for the fin base 15.

Although the semiconductor element 20 is made of silicon, the same effect can be obtained by constructing the semiconductor element 20 using a wide band gap semiconductor such as silicon carbide or gallium nitride.

For solder 30 and solder 31, a solder material consisting of 96.5% tin, 3% silver, 0.5% copper, with a melting point of 217°C was used, but the same effect can be obtained by using a solder material consisting of 99.3% tin, 0.7% copper, with a melting point of 224°C, etc. for solder 30 or solder 31.

The same effect can also be obtained by replacing the solder 31 used as the substrate bonding material for bonding the semiconductor element 20 to the ceramic substrate 10 or the block bonding material for bonding the metal block 60 to the ceramic substrate 10 with a silver sintered material or brazing material that has better heat resistance than solder.

The wires 41 to 43 used are made of aluminum, but the same effect can be obtained by using wires 41 to 43 made of aluminum alloy containing trace amounts of additives such as iron or copper. The same effect can also be obtained by using aluminum or copper ribbon bonds as an alternative material for the wires 41 to 43, or by soldering using a lead frame made of copper or the like.

As for the screw 61, if there is concern about noise due to the protruding shape, it is expected that this can be improved by using a "pan head screw", "low head screw" or a screw made of plastic.

Epoxy resin with dispersed silica filler was used as the potting sealing resin 7, but fillers such as alumina may also be used, and the same effect can be obtained by mixing epoxy resin with silicone resin or using silicone gel as the constituent material of the sealing resin 7.

In addition, in this specification, a case-type module in which sealing resin 7 is injected into case 5 is shown as the power module 1, but the same effect can be obtained by configuring it as a transfer mold type module in which the sealing resin is molded using a die.

The manufacturing method for the power module 1 described above includes the following steps (a) to (e) as a manufacturing method for a semiconductor device having a main terminal 62 for transmitting an external signal.

Step (a) is a step of preparing a ceramic substrate 10 as a substrate having a first and second main surfaces.

Step (b) is a step of mounting multiple semiconductor elements 20 on the surface of the upper conductor layer 12, which becomes the "first main surface of the substrate." Step (b) corresponds to the process described with reference to FIG. 4.

At least one of the ceramic substrate 10 and the semiconductor element 20 serves as a block mounting member. In the basic form of the first embodiment, the ceramic substrate 10 functions as the block mounting member.

Step (c) is a step of joining the ceramic substrate 10, which serves as the block mounting member, and the metal block 60 via the solder 31, which functions as a joining material for the block. Step (c) corresponds to the process described with reference to FIG. 4.

Step (d) is a step of forming sealing resin 7 to cover ceramic substrate 10, which serves as a block mounting member, and solder 31, which serves as a bonding material for the block. Step (d) corresponds to the process described with reference to Figures 6 and 7.

After step (d) is performed, the top surface and a portion of the upper part of the side surface of the metal block 60 are not covered by the sealing resin 7 and are exposed. Therefore, there is a pair of exposed side surfaces 60s and 60s that are exposed by about 2 mm from the sealing resin 7.

Step (d) includes the following steps (d-1) and (d-2).

Step (d-1) is a step of fixing the case 5, which is a member for forming a storage space and surrounds the ceramic substrate 10, the semiconductor element 20, and the metal block 60, onto the mounting surface 15s of the fin base 15. Step (d-1) corresponds to the process described with reference to FIG. 6.

Step (d-2) is a step of forming sealing resin 7 to cover ceramic substrate 10 and solder 31 in case housing space S5, which is an element housing space surrounded by case 5. Step (d-2) corresponds to the process described with reference to FIG. 7.

Step (e) is performed after the above-mentioned step (d) and is a step of attaching the main terminal 62 to the upper surface of the metal block 60. Step (e) corresponds to the process described with reference to FIG. 8.

The power module 1, which is a semiconductor device manufactured by the semiconductor device manufacturing method of the first embodiment, can reduce damage to the metal block 60 during the screw tightening process in step (e) by the sealing resin 7 that is provided to cover at least the ceramic substrate 10 that serves as the block mounting member and the solder 31 that serves as the block bonding material.

When step (e) of the method for manufacturing a semiconductor device according to the first embodiment is performed, the upper surface and a part of the upper side of the metal block 60 are not covered by the sealing resin 7 and are exposed. Therefore, rework in which the main terminal 62 attached to the upper surface of the metal block 60 is replaced with a new main terminal can be performed relatively easily without any problems as step (e).

In addition, as described above, the main terminal 62 can be fixed in a state where the metal block 60 is stably held by the pair of exposed side surfaces 60s and 60s, so damage to the solder 31 and the semiconductor element 20 when the main terminal 62 is fixed can be suppressed.

Furthermore, in step (d-2), by forming the sealing resin 7 in the case accommodation space S5 of the case 5 that was provided when step (d-1) was performed, the height of the sealing resin 7 can be adjusted relatively easily.

(Second Aspect)
Fig. 9 is an explanatory diagram showing a schematic cross-sectional structure of a power module 1B which is a semiconductor device according to a second aspect of the first embodiment. Fig. 9 corresponds to the cross-sectional structure taken along line A-A in Fig. 1 which shows the basic aspect. An XYZ orthogonal coordinate system is shown in Fig. 9.

With regard to the power module 1B, which is the second aspect of the first embodiment, components similar to those of the power module 1 of the basic aspect are given the same reference numerals and explanations thereof are omitted as appropriate. The following will focus on the characteristics of the power module 1B that differ from the power module 1 of the basic aspect shown in Figures 1 to 3.

As shown in FIG. 9, power module 1B differs from power module 1 in that the main terminals 62 are fixed to the top surface of the metal block 60 by a main terminal joining process such as laser welding. In other words, the main terminal attachment area for the metal block 60 of power module 1B is only the top surface of the metal block 60.

Therefore, unlike power module 1, power module 1B does not include screws 61 as a component, at least at the device completion stage.

As shown in FIG. 9, the welded portion 62w of the main terminal 62 is positioned on the top surface of the metal block 60, and a laser welding process is performed by irradiating a laser 65, and the welded portion 62w of the main terminal 62 is joined to the top surface of the metal block 60. Note that the laser 65 may be, for example, a YAG laser with an output of 5 kW. Thus, FIG. 9 shows the laser welding process as the main terminal joining process.

The metal block 60 may be made of copper or a copper alloy, and a nut made of brass or other material may also be used.

The power module 1B, which is the second aspect of the first embodiment, is provided with sealing resin 7 covering ceramic substrate 10, which serves as the block mounting member, and solder 31, which serves as the bonding material for the block.

Therefore, the sealing resin 7 can reduce damage to the metal block 60 when fixing the main terminal 62 by a main terminal joining process such as laser welding.

In addition, in the power module 1B, the sealing resin 7 is provided on the surface of the upper conductor layer 12, which is the first main surface of the substrate. Therefore, when the main terminals 62 are fixed to the metal block 60, the surface of the upper conductor layer 12 is protected by the sealing resin 7, and the performance of the ceramic substrate 10 is not degraded by welding spatters, etc., that occur when performing the main terminal joining process.

In this way, the power module 1B, which is the second aspect of the first embodiment, has a structure that does not adversely affect the ceramic substrate 10 during the manufacturing stage, and thus, like the basic aspect, it is possible to improve the yield and performance of the device.

The height-wise thickness (5 mm) of the metal block 60 in the power module 1B is sufficiently thicker than the film thickness (0.8 mm) of the upper conductor layer, so the metal block 60 has a relatively large heat capacity.

As a result, when performing a main terminal joining process such as laser welding to fix the main terminal 62 onto the upper surface of the metal block 60, the thermal effect on the ceramic substrate 10, which is an insulating substrate, can be suppressed by the metal block 60, which has a relatively large thermal capacity.

The power module 1B has the case 5 and fin base 15, just like the basic version, and therefore has the same effects as the power module 1, which is the basic version, with respect to the case 5 and fin base 15.

(Production method of the second embodiment)
The manufacturing method of the power module 1B described above is a manufacturing method of a semiconductor device having a main terminal 62 for transmitting an external signal, and includes the following steps (a) to (e).

Steps (a) to (d) are performed in the same manner as steps (a) to (d) of the manufacturing method for the power module 1, which is the basic embodiment.

Step (e) is performed after step (d) and is a step of attaching the main terminal 62 to the upper surface of the metal block 60 by a main terminal joining process such as laser welding.

The main terminal joining process will be described in detail below. A representative process for the main terminal joining process is laser welding. In the laser welding process described above, a YAG laser is used as the laser 65, but a carbon dioxide laser or a green laser can also be used instead of a YAG laser. Furthermore, instead of laser welding, resistance welding, MIG (Metal Inert Gas) welding, ultrasonic joining, etc. may also be used as the main terminal joining process. In this way, the main terminal 62 and the metal block 60 can be joined by the main terminal joining process, which includes a variety of processes.

When performing the above-mentioned main terminal joining process such as laser welding, there is a concern that the insulation of the device may be reduced due to scattering spatter. However, since the power module 1B covers the semiconductor element 20 and ceramic substrate 10 with sealing resin 7, even if spatter scatters, the insulation of the device including the semiconductor element 20 and ceramic substrate 10 is not affected.

In addition, the metal block 60 is sufficiently thick compared to the upper conductor layer 12 of the ceramic substrate 10 and has a relatively large heat capacity, so it can absorb the excessive heat energy generated during the main terminal bonding process and suppress thermal damage to the upper conductor layer 12 and the ceramic base material 11.

Furthermore, the main terminal joining process may be performed using solder. Hereinafter, the solder used in this main terminal joining process will be referred to as "main terminal solder." The welded fixing portion 62w of the main terminal 62 can be fixed to the upper surface of the metal block 60 via the main terminal solder.

In this case, by using a main terminal solder that has a lower melting point than the solder 31 used to join the upper conductor layer 12 of the ceramic substrate 10 to the metal block 60, remelting of the internal solder, including the solders 30 and 31, can be suppressed when performing the main terminal joining process using the main terminal solder.

The screw 61 may be used to position the welded fixing portion 62w of the main terminal 62 on the upper surface of the metal block 60. That is, after the main terminal joining process is performed in a state in which the main terminal 62 is temporarily fixed on the upper surface of the metal block 60 by the screw 61, the screw 61 may be removed from the metal block 60 to complete the power module 1B. That is, the screw 61 may be used for temporary positioning and fixing used in an intermediate stage during the manufacture of the power module 1B.

In this case, it is desirable to set the tightening torque of the screw 61 so that the shear strength of the main terminal 62 after tightening is smaller than the shear strength of the solder 31 to the ceramic substrate 10 of the metal block 60. This is because the above setting makes it possible to suppress damage to the solder 31, which is the soldered portion, due to thermal stress caused by the difference in the expansion coefficient between the components.

When using the screw 61, it is necessary to provide an opening 62o in the welded fixing portion 62w. In this case, by making the diameter of the opening 62o, which is the screw fastening opening of the main terminal 62, 1.5 times or more the thread diameter of the screw 61, it is possible to ensure better temperature cycle resistance.

The power module 1B, which is a semiconductor device manufactured by the manufacturing method of the second aspect, can reduce damage to the metal block 60 during the main terminal joining process such as laser welding in step (e) by using the sealing resin 7 that covers the ceramic substrate 10 and the solder 31.

When performing step (e) of the manufacturing method of the second embodiment, the upper surface of the metal block 60 is not covered with the sealing resin and is exposed. Therefore, rework can be performed relatively easily as step (e) by removing the main terminal 62 fixed on the upper surface of the metal block 60 and replacing it with a new main terminal by a main terminal joining process.

(Third Aspect)
Fig. 10 is an explanatory diagram showing a schematic cross-sectional structure of a power module 1C which is a semiconductor device according to a third aspect of the first embodiment. Fig. 10 corresponds to the cross-sectional structure taken along line A-A in Fig. 1 which shows the basic aspect. An XYZ orthogonal coordinate system is shown in Fig. 10.

With regard to the power module 1C, which is the third aspect of the first embodiment, components similar to those of the power module 1 of the basic aspect are given the same reference numerals and explanations are omitted as appropriate. The following will focus on the characteristics of the power module 1C that are different from the power module 1 of the basic aspect shown in Figures 1 to 3.

As shown in FIG. 10, the power module 1C is provided with a case 5T with main terminals instead of the case 5. The planar shape of the case 5T with main terminals in the XY plane is set to, for example, 92 mm x 80 mm, similar to the case 5, and it is desirable that the height of the case 5T with main terminals in the Z direction is slightly higher than 10 mm. As with the case 5, the material of the case 5T with main terminals may be PPS resin.

Therefore, in the power module 1C, the planar shape (100 mm x 100 mm) of the mounting surface 15s of the fin base 15 has dimensional characteristics that are wider than the planar shape (92 mm x 80 mm) of the main terminal case 5T.

The main terminal 62 is connected to the case 5T with the main terminal in such a manner that the main terminal 62 protrudes from the case housing space S5 to the outside. In other words, the main terminal 62 is insert molded into the case 5T with the main terminal.

Therefore, in addition to the screw attachment portion 62a, the main terminal 62 has an externally exposed portion 62b that protrudes from the main terminal case 5T in the X direction, and an internal case insertion portion 62c that exists within the main terminal case 5T.

In the power module 1B, sealing resin 72 is further provided on the sealing resin 7 within the case housing space S5. The upper part of the metal block 60 exposed from the sealing resin 7, the screw mounting parts 62a of the main terminals 62, and the screws 61 are all covered with sealing resin 72.

(Production method of the third embodiment)
The manufacturing method of the power module 1C described above is a manufacturing method of a semiconductor device having a main terminal 62 for transmitting an external signal, and includes the following steps (a) to (e) and step (x).

Steps (a) and (b) are performed in the same manner as steps (a) and (b) of the method for manufacturing the power module 1.

Step (c) is a step in which the ceramic substrate 10, which serves as the block mounting member, and the metal block 60 are joined via solder 31, which is a joining material for the block. Prior to the execution of step (c), the main terminal case 5T is fixed onto the mounting surface 15s of the fin base 15.

When the case 5T with main terminals is fixed, the screw attachment portion 62a of the main terminals 62 is positioned so that it contacts the upper surface of the metal block 60. In other words, the metal block 60 and the main terminals 62 are set so that they can be positioned when the case 5T with main terminals is mounted on the mounting surface 15s of the fin base 15.

Step (d) is performed in the same manner as step (d) in the method for manufacturing the power module 1.

Step (e) is performed after step (d) and is a step of attaching the main terminal 62 to the upper surface of the metal block 60.

When the main terminal 62 is fastened to the top surface of the metal block 60 by the screw 61 during step (e), the stress generated during fastening is also distributed to the main terminal case 5T, thereby reducing the stress on the metal block 60. In addition, Joule heat (resistance heat) generated during fastening can be diffused to the fin base 15 via the main terminal case 5T.

Furthermore, it is possible to use the screw 61 for fastening and then use a laser welding process by irradiating a laser. When performing the laser welding process, a gap at the joint between the screw attachment portion 62a and the upper surface of the metal block 60 may affect the joining quality, but by also using the screw 61 for fastening, the above-mentioned gap can be minimized. Furthermore, by removing the screw 61 after the laser welding process, it is possible to suppress the generation of noise caused by the screw 61 being present as a protrusion.

Step (x) is a step in which sealing resin 72 is further formed on the sealing resin 7 within the case housing space S5, and the metal block 60, the main terminals 62, and the screw mounting portions 62a are all covered with the sealing resin 72.

This step (x) is a process specific to power module 1C that is not performed in power module 1 or power module 1B.

In step (x), sealing resin 72 is injected into the case housing space S5 of the main terminal case 5T to insulate and seal the exposed parts of the metal block 60 and the screws 61, etc., thereby improving insulation and reducing noise caused by the shape of the heads 61a of the screws 61, etc.

The second sealing resin, sealing resin 72, may be made of the same material as sealing resin 7, but it may also have a lower filler content than sealing resin 7 to increase fluidity, or it may be replaced with an inexpensive silicone gel.

The third embodiment of the power module 1C has the same effects as the basic embodiment of the power module 1, except for the effects resulting from the upper surface of the metal block 60 being exposed at the completed stage, and further has the following effects:

The power module 1C has sealing resin 72 in addition to sealing resin 7 as the sealing resin provided in the case housing space S5, so that the ceramic substrate 10, the multiple semiconductor elements 20, the metal block 60, and the screw mounting portion 62a of the main terminal 62 that are present in the case housing space S5 are all covered with sealing resin 7 and sealing resin 72.

As a result, the power module 1C improves the insulation of the device and reduces noise caused by protrusions such as the head 61a that remain when the top surface of the metal block 60 is fixed to the screw mounting portion 62a of the main terminal 62.

In the power module 1 of embodiment 1, a pair of exposed side surfaces 60s and 60s that are parallel to the Y direction and face each other in the X direction are shown as a pair of exposed side surfaces for restraint in the metal block 60. However, a pair of exposed side surfaces that are parallel to the X direction and face each other in the Y direction may also be used as a pair of exposed side surfaces for restraint.

In addition, in the first embodiment, the metal block 60 is shown in the shape of a rectangular prism, but the metal block 60 may be in the shape of a polygonal prism of hexagonal or greater prism that can be provided with a pair of exposed side surfaces 60s and 60s.

<Embodiment 2>
(Basic form)
Hereinafter, a power module 2 that is a semiconductor device according to a basic aspect of the second embodiment of the present disclosure will be described.

FIG. 11 is an explanatory diagram that shows a schematic planar structure of the power module 2. FIG. 12 is an explanatory diagram that shows a schematic cross-sectional structure taken along line B-B of FIG. 11. An XYZ orthogonal coordinate system is shown in each of FIG. 11 and FIG. 12.

With regard to power module 2B, which is the basic aspect of embodiment 2, components similar to those of power module 1, which is the basic aspect of embodiment 1, are given the same reference numerals and explanations are omitted as appropriate. The following will focus on the characteristics of power module 2 that are different from power module 1 shown in Figures 1 to 3.

As shown in Figures 11 and 12, a fin base 15B, which is a heat dissipation fin, is provided on the bottom layer of the power module 2. The fin base 15B has a base portion 15m and a number of pins 15p. The planar shape of the base portion 15m is, for example, 90 mm x 100 mm, and the thickness of the base portion 15m is set to, for example, 3 mm. Possible materials for the base portion 15m include, for example, copper and nickel plating.

A dam section 8 is provided on the mounting surface 15s of the fin base 15B, surrounding the ceramic substrate 10B, the semiconductor elements 20, and the metal blocks 66. The height of the dam section 8, which is a member forming the storage space, in the Z direction is set to, for example, about 6 mm. As shown in FIG. 11, four semiconductor elements 20 are shown as the multiple semiconductor elements 20 in the power module 2.

The dam section 8 is constructed by stacking multiple dam materials 81. A process for obtaining a layered structure using multiple dam materials 81 can be, for example, a drawing process using a dispenser. A material obtained by dispersing silica filler in epoxy resin can be used as a constituent material for the dam material 81.

The ceramic substrate 10B, which is an insulating substrate, has a silicon nitride substrate 11B that serves as an insulating base material, an upper conductor layer 12 provided on the upper surface of the silicon nitride substrate 11B, and a lower conductor layer 13 provided on the lower surface of the ceramic substrate 10B. The surface of the upper conductor layer 12 becomes the first main surface of the substrate, and the surface of the lower conductor layer 13 becomes the second main surface of the substrate.

The planar shape of the silicon nitride substrate 11B is, for example, 65 mm x 58 mm, and the thickness of the silicon nitride substrate 11B in the Z direction is set to, for example, 0.32 mm.

The solder 30, which serves as the bonding material for the board, is composed of, for example, 96.5% tin, 3% silver, and 0.5% copper, and the melting point of the solder 30 is set to, for example, 217°C.

The thickness of each of the upper conductor layer 12 and the lower conductor layer 13 is set to, for example, 0.8 mm, and the constituent material is, for example, copper.

A number of semiconductor elements 20 are mounted on the surface of the upper conductor layer 12 of the ceramic substrate 10B via solder 31. In other words, the first main surface of the substrate and the number of semiconductor elements 20 are joined via the solder 31.

The multiple semiconductor elements 20 may be diodes or IGBTs. The diodes may be made of silicon, have a planar configuration of, for example, 10 mm x 8 mm, and have a thickness of, for example, 0.2 mm. The IGBTs may be made of silicon, have a planar configuration of, for example, 10 mm x 10 mm, and have a thickness of, for example, 0.2 mm.

A terminal block 51 is provided on a portion of the upper conductor layer 12 of the ceramic substrate 10B. A signal terminal 63 is fixed to the terminal block 51 in such a manner that a portion of the signal terminal 63 is inserted into the terminal block 51. The signal terminal 63 is made of copper, for example, and has a width in the Y direction of, for example, 1.5 mm and a thickness of, for example, 0.6 mm.

The terminal block 51 has a terminal horizontal portion 51a and a terminal standing portion 51b, and the signal terminal 63 has a bent shape consisting of the terminal horizontal portion 63a and the terminal standing portion 63b, with the terminal horizontal portion 63a being inserted into the terminal horizontal portion 51a and a part of the terminal standing portion 63b being inserted into the terminal standing portion 51b. In this way, the signal terminal 63 is insert molded into the terminal block 51.

A portion of the upper surface of the terminal horizontal portion 63a of the signal terminal 63 is exposed from the terminal horizontal section 51a, and the upper surface of the exposed terminal horizontal portion 63a is electrically connected to the upper surface of the semiconductor element 20 by a wire 41. For example, an aluminum wire having a diameter of 0.15 mm is used as the wire 41. The signal terminal 63 and the wire 41 form a signal circuit.

Similar to the power modules 1, 1B, and 1C of the first embodiment, in the power module 2, the metal block 60 is fixed to the surface of the upper conductor layer 12 of the ceramic substrate 10B by solder 31. The solder 31 used to join the metal block 60 serves as a joining material for the block.

Furthermore, as shown in FIG. 12, a metal block 66 is fixed onto each of the semiconductor elements 20 by solder 32, which is a bonding material for the block.

In the second embodiment, for convenience of explanation, the metal block is divided into a metal block 60 provided on the surface of the upper conductor layer 12 of the ceramic substrate 10B and a metal block 66 provided on the semiconductor element 20. However, the constituent materials and shapes of the metal blocks 60 and 66 are the same.

As shown in FIG. 11, the power module 2 includes four semiconductor elements 20, two metal blocks 60, and four metal blocks 66.

The metal blocks 60 and 66 are made of brass, for example, and each has a rectangular shape measuring 7 mm x 6 mm in plan view, with each having a height of 5 mm along the Z direction. In other words, the metal blocks 60 and 66 each have a rectangular prism shape. The metal block 60 has a screw hole region 60x that runs from the center of the top surface to the bottom surface. Similarly, the metal block 66 has a screw hole region 66x that runs from the top surface to the bottom surface.

In this way, the screw hole regions 60x and 66x that penetrate the metal blocks 60 and 66 along the height direction function as main terminal mounting regions, respectively.

Therefore, the thickness (5 mm) of each of the metal blocks 60 and 66 in the height direction along the Z direction is set to be sufficiently thick compared to the film thickness (0.8 mm) of the upper conductor layer 12.

In the power module 2, the ceramic substrate 10B and the semiconductor element 20 function as block mounting members. That is, solder 31 is used as a block bonding material between the ceramic substrate 10B, which serves as the block mounting member, and the metal block 60, and solder 32 is used as a block bonding material between the semiconductor element 20, which serves as the block mounting member, and the metal block 66.

As shown in FIG. 12, one main terminal 67 is fixed to the top surfaces of two metal blocks 66 by two screws 61. The main terminal 67 has two openings 67o in the screw attachment portion 67a. The main terminal 67 is made of copper, for example, and has a width of 8 mm in the Y direction and a thickness of 1 mm.

The end of the main terminal 67 opposite the screw attachment portion 67a is provided so as to protrude from the case housing space S5 to the outside. Note that the main terminal 67 may be a bus bar or a terminal for an external wiring cable.

One main terminal 67 is fixed onto the top surface of two metal blocks 66 in an installation manner in which the threaded portions 61b of two screws 61 are inserted into the two openings 67o of the main terminal 67 and the screw hole areas 66x of the two metal blocks 66.

In this way, the metal block 66 has an upper surface and a screw hole area 66x as a main terminal mounting area, and the main terminal 67 is fixed to the metal block 66 in the main terminal mounting area by the screw 61.

The main circuit of the power module 2 includes metal blocks 60 and 66, a screw 61, and a main terminal 67 as components.

In the dam portion accommodation area S8 surrounded by the dam portion 8, sealing resin 7 is provided to cover the solder 30, ceramic substrate 10B, solder 31, multiple semiconductor elements 20, solder 32, and wires 41 to 43 provided on the mounting surface 15s of the fin base 15. The constituent material of the sealing resin 7 may be, for example, an epoxy resin with silica filler dispersed therein.

The top surface and a portion of the upper side of the metal block 66 are not covered by the sealing resin 7 and are exposed. For example, the dam portion housing area S8 is sealed with the sealing resin 7 to a depth of about 4 mm, and the metal block 66 is exposed about 2 mm from the top surface.

In other words, an upper portion of the side of the metal block 66 is not covered by the sealing resin 7 and is exposed, and the exposed side of the metal block 66 includes a pair of exposed side surfaces 66s and 66s that are parallel to the Y direction and face each other in the X direction.

Since the pair of exposed side surfaces 66s and 66s are exposed from the sealing resin 7 by about 2 mm, the metal block 66 can be restrained by clamping the pair of exposed side surfaces 66s and 66s using an existing restraining tool.

The exposed width and exposed length of the exposed side surface 66s must be set to a length that allows the metal block 66 to be restrained using an existing restraining tool.

The power module 2 has a dam portion housing area S8 in the dam portion 8 as an element housing space that houses the ceramic substrate 10B, the multiple semiconductor elements 20, and the metal blocks 60 and 66. The sealing resin 7 is provided in the dam portion housing area S8.

In the power module 2, in addition to the ceramic substrate 10B, a semiconductor element 20 is used as a block mounting member. The module metal block used in the power module 2 includes a metal block 60 provided on the ceramic substrate 10B and a metal block 66 provided on the power module 2.

In this way, the power module 2 has metal blocks 66 in addition to the metal blocks 60 as metal blocks for the module. As shown in FIG. 11, the power module 2 has four metal blocks 66 and two metal blocks 60.

Therefore, the power module 2 can reduce the number of metal blocks 60. Specifically, compared to the power module 1 of the first embodiment, the power module 2 reduces the number of metal blocks 60 from "three" to "two," and increases the total number of metal blocks for the module from "three" to "six."

In this way, by reducing the number of metal blocks 60, the power module 2 can reduce the area of the relatively expensive ceramic substrate 10B.

Specifically, between the ceramic substrate 10 and the ceramic substrate 10B of the first embodiment, the silicon nitride substrate 11 having a planar shape of 70 mm x 58 mm can be reduced in size to the silicon nitride substrate 11B having a planar shape of 65 mm x 58 mm.

By reducing the size of the ceramic substrate 10B, it is possible to reduce the thermal stress caused by the large difference in the expansion coefficient between the fin base 15B and the ceramic substrate 10B, thereby improving the reliability of the device.

The power module 2, which is the basic form of the second embodiment, is provided with a sealing resin 7 covering the ceramic substrate 10B, the semiconductor element 20, the solder 31, and the solder 32.

Therefore, like power module 1, which is the basic aspect of embodiment 1, power module 2, which is the basic aspect of embodiment 2, has a structure that does not adversely affect ceramic substrate 10B during the manufacturing stage, and therefore it is possible to improve the device's performance, including its yield and insulation properties.

Furthermore, the upper surfaces of the metal blocks 60 and 66 in the power module 2 are not covered with the sealing resin 7 and are exposed. Therefore, even after the device is completed, rework can be performed relatively easily by using the screw 61 to replace the main terminal 67 fixed on the upper surface of the metal block 66 with a new main terminal. Similarly, even after the device is completed, rework can be performed relatively easily by using the screw 61 to replace the main terminal 62 fixed on the upper surface of the metal block 60 with a new main terminal. Therefore, flexibility can be provided when selecting the main terminals 62 and 67.

In addition, when the power module 2 is completed, it has the same effects as the basic power module 1, except for the effects attributable to the case 5, and further has the following effects:

Furthermore, by providing the sealing resin 7 in the dam portion accommodation area S8 of the dam portion 8 provided on the mounting surface 15s of the fin base 15B, the power module 2 makes it relatively easy to adjust the height of the sealing resin 7 during manufacturing without the need for a dedicated case.

(Production method of the basic embodiment)
13 to 17 are explanatory diagrams that show a schematic cross-sectional structure during the manufacturing process of the power module 2. An XYZ orthogonal coordinate system is shown in each of Fig. 13 to 17. The manufacturing method of the power module 2 will be described below with reference to Fig. 13 to 17.

As shown in Figures 11 and 12, the power module 2 includes four semiconductor elements 20, four metal blocks 66, and two metal blocks 60, but for convenience of explanation, the structure shown in Figures 13 to 17 will be used as the basis for explanation. The process for forming the metal blocks 60, which are not shown in Figures 13 to 17, is the same as the manufacturing method of the first embodiment shown in Figures 4 to 8.

First, a ceramic substrate 10B is prepared as the substrate for the semiconductor device of the second embodiment. In the power module 2, the ceramic substrate 10B and the semiconductor element 20 serve as block mounting members.

Next, as shown in FIG. 13, solder 31 and two semiconductor elements 20 are positioned above the upper conductor layer 12 of the ceramic substrate 10B, and solder 32 and two metal blocks 66 are positioned above the two semiconductor elements 20, and solder bonding is performed using the solders 31 and 32 in a reflow furnace.

As a result, two semiconductor elements 20 are mounted on the surface of the upper conductor layer 12 of the ceramic substrate 10B via solder 31, and two metal blocks 66 are mounted on the upper surfaces of the two semiconductor elements 20 via solder 32. That is, the metal blocks 66 are joined via solder 32 to the upper surfaces of the semiconductor elements 20 that serve as block mounting members. Although not shown in FIG. 13, as in embodiment 1, a metal block 60 is joined via solder 31 to the surface of the upper conductor layer 12 of the ceramic substrate 10B that serves as the block mounting member.

Then, as shown in FIG. 14, the surface of the lower conductor layer 13 of the ceramic substrate 10B is joined to the mounting surface 15s of the fin base 15B via solder 30. In other words, the fin base 15B, which is a heat dissipation fin, is fixed to the surface of the lower conductor layer 13 of the ceramic substrate 10B.

Next, as shown in FIG. 15, a plurality of dam materials 81 are stacked on the mounting surface 15s of the fin base 15B to form the dam portion 8. The stacking process of the dam materials 81 is performed, for example, by a coating process using a dispenser. The completed dam portion 8 has a dam portion accommodation area S8, and the dam portion 8 is provided on the mounting surface 15s of the fin base 15B so that the solder 30 and the ceramic substrate 10B are present within the dam portion accommodation area S8.

At the same time, the terminal block 51 is adhered and fixed onto a portion of the surface of the upper conductor layer 12 of the ceramic substrate 10B. The signal terminal 63 is integrated with the terminal block 51, with the terminal horizontal portion 63a provided within the terminal horizontal portion 51a and a portion of the terminal standing portion 63b provided within the terminal standing portion 51b. After the terminal block 51 is fixed to the fin base 15B, a portion of the surface of the terminal horizontal portion 63a is exposed.

After the dam portion 8 is formed and fixed to the fin base 15B of the terminal block 51, wiring is performed using the wires 41. That is, the surface of the terminal horizontal portion 63a and the semiconductor element 20 are electrically connected by the wires 41. After wiring the wires 41, a circuit is formed that includes multiple semiconductor elements 20, the wires 41, the metal blocks 60 and 66, and the signal terminals 63.

Next, as shown in FIG. 16, sealing resin 7 is injected into the dam portion housing area S8 and heated to harden so that a portion of the upper surface and upper side of each of the two metal blocks 66 is exposed. Therefore, a portion of the upper surface and upper side of each of the two metal blocks 66 is not covered by the sealing resin 7 and is exposed.

In other words, the side of the exposed metal block 66 includes a pair of exposed side surfaces 66s and 66s that face each other in the X direction. The pair of exposed side surfaces 66s and 66 are both parallel to the YZ plane. Furthermore, no sealing resin 7 is provided in the screw hole region 66x.

On the other hand, within the dam portion accommodation area S8, the solder 30, the ceramic substrate 10B, the solder 31, the two semiconductor elements 20, the solder 32 and the wire 41 are all covered with the sealing resin 7.

Finally, as shown in FIG. 17, the screw hole regions 66x of the two metal blocks 66 are positioned so that they match the two openings 62o of the main terminal 67 in a plan view, and the metal blocks 66 and the main terminal 67 are connected and fixed using two screws 61.

In other words, the main terminal 67 is fixed onto the top surface of the metal block 66 in an installation manner in which the threaded portions 61b of the two screws 61 are inserted into the two openings 62o of the main terminal 67 and into the screw hole regions 66x of each of the two metal blocks 66.

As shown in FIG. 17, the two metal blocks 66 are sealed partway with the sealing resin 7, so when the main terminal 67 is attached to the top surface of the metal block 66 with the two screws 61, the tightening torque of each of the two screws 61 reduces damage to the solder 32, which forms the joint between the metal block 66 and the semiconductor element 20. To maximize this effect, it is desirable to set the depth of the sealing resin 7 so that the sealing resin 7 is present up to 20% or more of the height of the metal block 66.

In addition, since the pair of exposed side surfaces 66s and 66s are exposed from the sealing resin 7 by about 2 mm, the metal block 66 can be restrained by clamping the pair of exposed side surfaces 66s and 66s using an existing restraining tool.

Therefore, with the metal block 66 stably fixed, the threaded portion 61b of the screw 61 is inserted into the opening 67o of the main terminal 67 and the threaded hole area 66x of the metal block 66, and then the screw 61 is tightened with a predetermined torque, thereby fastening and fixing the main terminal 67 to the upper surface of the metal block 66.

In this way, the main terminal 67 can be fixed with the metal block 66 stably restrained by the pair of exposed side surfaces 66s and 66s, which further reduces damage to the solder 31, which is the bonding material for the fixed block, when the main terminal 67 is fixed, and also reduces damage to the semiconductor element 20.

In addition, in this specification, a dam-type module in which sealing resin 7 is injected into dam section 8 is shown as the power module 2, but the same effect can be obtained by configuring it as a transfer mold type module in which the sealing resin is molded using a die.

The manufacturing method for the power module 2 described above includes the following steps (a) to (e) as a manufacturing method for a semiconductor device having a main terminal 67 for transmitting an external signal.

Step (a) is a step of preparing a ceramic substrate 10B as a substrate having a first and second main surfaces.

Step (b) is a step of mounting multiple semiconductor elements 20 on the surface of the upper conductor layer 12, which becomes the "first main surface of the substrate." Step (b) corresponds to the process described with reference to FIG. 13. In the basic aspect of the second embodiment, the ceramic substrate 10 and the semiconductor elements 20 function as block mounting members.

Step (c) is a step of joining the ceramic substrate 10, which serves as the block mounting member, and the metal block 60 via solder 31, which serves as a bonding material for the block, and joining the semiconductor element 20, which serves as the block mounting member, and the metal block 66 via solder 32, which serves as a bonding material for the block. Step (c) corresponds to the process described with reference to FIG. 13.

Step (d) is a step of forming sealing resin 7 to cover ceramic substrate 10 and semiconductor element 20, which are block mounting members, as well as solders 31 and 32. Step (d) corresponds to the process described with reference to Figures 15 and 16.

After step (d) is performed, the upper surfaces and upper portions of the sides of the metal blocks 60 and 66 are not covered by the sealing resin 7 and are exposed. Therefore, there are a pair of exposed side surfaces 60s and 60s and a pair of exposed side surfaces 66s and 66s that are exposed by about 2 mm from the sealing resin 7.

Step (d) includes the following steps (d-1) and (d-2).

Step (d-1) is a step of forming the dam portion 8, which is a member for forming the storage space, around the ceramic substrate 10, the semiconductor element 20, and the metal blocks 60 and 66 on the mounting surface 15s of the fin base 15. Step (d-1) corresponds to the process described with reference to FIG. 15.

Step (d-2) is a step of forming sealing resin 7 to cover ceramic substrate 10B, semiconductor element 20, and solders 31 and 32 within dam portion accommodation area S8, which is an element accommodation space surrounded by dam portion 8. Step (d-2) corresponds to the process described with reference to FIG. 16.

Step (e) is performed after step (d) described above, and is a step of attaching main terminals 62 and 67 to the upper surfaces of metal blocks 60 and 66, respectively. Step (e) corresponds to the process described with reference to FIG. 17.

The power module 2, which is a semiconductor device manufactured by the semiconductor device manufacturing method of the second embodiment, can reduce damage to the metal blocks 60 and 66 during the screw tightening process in step (e) by using the sealing resin 7 that covers the ceramic substrate 10B, the semiconductor element 20, and the solders 31 and 32.

When step (e) of the method for manufacturing a semiconductor device according to the second embodiment is performed, the upper surfaces and upper portions of the side surfaces of the metal blocks 60 and 66 are not covered by the sealing resin 7 and are exposed. Therefore, rework in which the main terminals 62 and main terminals 67 attached to the upper surfaces of the metal blocks 60 and 66 are replaced with new main terminals can be performed relatively easily without any problems as step (e).

In addition, as described above, the main terminal 62 can be fixed in a state where the metal block 60 is stably held by the pair of exposed side surfaces 60s and 60s, so damage to the solder 31 and the semiconductor element 20 when the main terminal 62 is fixed can be suppressed.

Similarly, the main terminal 67 can be fixed in place while the metal block 66 is stably held by the pair of exposed side surfaces 66s and 66s, so damage to the solder 31 and the semiconductor element 20 when the main terminal 67 is fixed can be suppressed.

Furthermore, in the manufacturing method of the second embodiment, in step (d-2), the sealing resin 7 is formed in the dam portion accommodation area S8 of the case 5 that was provided when step (d-1) was performed, making it relatively easy to adjust the height of the sealing resin 7.

(Second Aspect)
Fig. 18 is an explanatory diagram showing a schematic cross-sectional structure of a power module 2B which is a semiconductor device according to a second aspect of the second embodiment. Fig. 18 corresponds to the cross-sectional structure taken along line B-B in Fig. 11 which shows the basic aspect. An XYZ orthogonal coordinate system is shown in Fig. 18.

With regard to the power module 2B, which is the second aspect of the second embodiment, components similar to those of the power module 2 of the basic aspect are given the same reference numerals and explanations thereof are omitted as appropriate. The following will focus on the characteristics of the power module 2B that are different from the power module 2 of the basic aspect shown in Figures 11 and 2.

Power module 2B differs from power module 2 in that it does not have a dam section 8, a terminal block 51, or a signal terminal 63. In power module 2B, instead of the terminal block 51 and the signal terminal 63, pin terminals 64 are provided in an upright state directly on the surface of the upper conductor layer 12 of the ceramic substrate 10. In addition, in the upper conductor layer 12, the area under the pin terminals 64 and the area under the multiple semiconductor elements 20 are electrically separated.

The area of the upper conductor layer 12 below the pin terminal 64 and the semiconductor element 20 are electrically connected by a wire 41.

Furthermore, in the power module 2B, sealing resin 7B, which has a higher viscosity than sealing resin 7, is used instead of sealing resin 7. Therefore, without providing a dam portion 8, sealing resin 7B is provided on the mounting surface 15s of the fin base 15B, and a structure is realized in which the solder 30-32, ceramic substrate 10B, semiconductor element 20, wire 41, part of the pin terminal 64, and part of the metal block 66 are covered with sealing resin 7B.

The second embodiment, power module 2B, has the same effects as the basic embodiment, power module 2, except for the effect of providing the dam section 8.

Furthermore, the power module 2B does not have a dam portion 8, which has the effect of simplifying the manufacturing process. Specifically, when manufacturing the power module 2B, the process described with reference to FIG. 15 is not necessary.

(Production method of the second embodiment)
The manufacturing method of the power module 2B described above includes the following steps (a) to (e) as a manufacturing method of a semiconductor device having a main terminal 67 for transmitting an external signal.

Steps (a) to (c) are the same as steps (a) to (c) in the manufacturing method of power module 2.

Step (d) is a step of forming sealing resin 7B to cover ceramic substrate 10 and semiconductor element 20, which are block mounting members, as well as solders 31 and 32. Step (d) corresponds to the process described with reference to FIG. 16. After step (d) is performed, a portion of the upper part of the top surface and side surfaces of each of metal blocks 60 and 66 is not covered by sealing resin 7B and is exposed.

In the manufacturing method of the power module 2B, the manufacturing process of step (d) can be simplified by not performing the process of forming the dam portion 8 shown in step (d-1) of the basic embodiment.

Step (e) is the same as step (e) in the manufacturing method of power module 2.

The manufacturing method for power module 2B has the same effect as the manufacturing method for power module 2, and further has the effect of simplifying the manufacturing process of step (d) described above.

In the power module 2 of the second embodiment, the pair of exposed side surfaces for restraint in the metal blocks 60 and 66 are shown as exposed side surfaces 60s and 60s, and exposed side surfaces 66s and 66s, which are parallel to the Y direction and face each other in the X direction.

Instead of the pair of exposed side surfaces 60s and 60s and the pair of exposed side surfaces 66s and 66s, a pair of exposed side surfaces parallel to the X direction and facing each other in the Y direction may be used as a pair of exposed side surfaces for restraining the metal blocks 60 and 66, respectively.

In addition, in the second embodiment, the metal blocks 60 and 66 are shown to have a rectangular prism shape, but the metal blocks 60 and 66 may each be shaped like a polygonal prism of hexagonal or greater size on which a pair of exposed side surfaces 60s and 60s or a pair of exposed side surfaces 66s and 66s can be provided.

<Third embodiment>
Hereinafter, a power module 3 serving as a semiconductor device according to a third embodiment of the present disclosure will be described.

FIG. 19 is an explanatory diagram that shows a schematic planar structure of the power module 3. FIG. 20 is an explanatory diagram that shows a schematic cross-sectional structure taken along the line C-C of FIG. 19. An XYZ orthogonal coordinate system is shown in each of FIG. 19 and FIG. 20.

With regard to the power module 3 which is the basic aspect of the third embodiment, the same components as those of the power module 1 which is the basic aspect of the first embodiment and the power module 2 which is the basic aspect of the second embodiment are given the same reference numerals and the description thereof is omitted as appropriate. The following description will focus on the characteristic features of the power module 3 which are different from the power module 1 shown in Figures 1 to 3 or the power module 2 shown in Figures 11 and 12.

The ceramic substrate 10C, which is an insulating substrate, has a silicon nitride substrate 11C that serves as an insulating base material, an upper conductor layer 12 provided on the upper surface of the silicon nitride substrate 11C, and a lower conductor layer 13 provided on the lower surface of the ceramic substrate 10C. The surface of the upper conductor layer 12 becomes the first main surface of the substrate, and the surface of the lower conductor layer 13 becomes the second main surface of the substrate.

The planar shape of the silicon nitride substrate 11C is, for example, 90 mm x 75 mm, and the thickness of the silicon nitride substrate 11C in the Z direction is set to, for example, 0.32 mm.

The power module 3 has a fin base 15, which is a heat dissipation fin, fixed to the surface of the lower conductor layer 13 of the ceramic substrate 10C via a heat dissipation sheet 73.

A dam portion 9 is provided circumferentially on the silicon nitride base material 11C of the ceramic substrate 10C, surrounding the upper conductor layer 12, the multiple semiconductor elements 20, and the multiple metal blocks 66. The formation height of the dam portion 9, which is a member forming the storage space, in the Z direction is set to, for example, about 6 mm. The multiple semiconductor elements 20 may be diodes or IGBTs.

Similar to the dam section 8 in the second embodiment, the dam section 9 is constructed by stacking a plurality of dam materials 81. As a process for stacking a plurality of dam materials 81, for example, a drawing process using a dispenser can be considered.

The main circuit of the power module 3 includes metal blocks 60 and 66, a screw 61, and a main terminal 67 as components.

In the dam portion accommodation area S9 surrounded by the dam portion 9, sealing resin 7 is provided to cover the solder 30, ceramic substrate 10C, solder 31, multiple semiconductor elements 20, solder 32, and wires 41 provided on the mounting surface 15s of the fin base 15. The sealing resin 7 may be made of, for example, epoxy resin with silica filler dispersed therein.

The top surface and a portion of the upper side of each metal block 66 are not covered with the sealing resin 7 and are exposed. For example, the dam portion housing area S9 is sealed with the sealing resin 7 to a depth of about 4 mm, and the metal block 60 is exposed about 2 mm from the top surface.

In other words, similar to embodiment 2, the side of the exposed metal block 66 includes a pair of exposed side surfaces 66s and 66s that are parallel to the Y direction and face each other in the X direction.

Since the pair of exposed side surfaces 66s and 66s are exposed from the sealing resin 7 by about 2 mm, the metal block 66 can be restrained by clamping the pair of exposed side surfaces 66s and 66s using an existing restraining tool.

The power module 3 has a dam portion housing area S9 in the dam portion 9 as an element housing space that houses the ceramic substrate 10C, the multiple semiconductor elements 20, and the metal blocks 60 and 66. The sealing resin 7 is provided in the dam portion housing area S9.

The power module 3, which is the basic form of the third embodiment, is provided with a sealing resin 7 covering the ceramic substrate 10C, the semiconductor element 20, the solder 31, and the solder 32.

Therefore, like the power module 1, which is the basic aspect of the first embodiment, the power module 3, which is the basic aspect of the third embodiment, has a structure that does not adversely affect the ceramic substrate 10C during the manufacturing stage, and therefore it is possible to improve the performance, including the yield and insulation properties, of the device.

Furthermore, the upper surfaces of the metal blocks 60 and 66 in the power module 3 are not covered with the sealing resin 7 and are exposed. Therefore, even after the device is completed, rework can be performed relatively easily by using the screw 61 to replace the main terminal 67 fixed on the upper surface of the metal block 66 with a new main terminal. Similarly, even after the device is completed, rework can be performed relatively easily by using the screw 61 to replace the main terminal 62 fixed on the upper surface of the metal block 60 with a new main terminal. Therefore, flexibility can be provided when selecting the main terminals 62 and 67.

In addition, when the power module 3 is completed, it provides the same effects as the basic power module 1, except for the effects attributable to the case 5, and further provides the following effects:

In addition, by providing the sealing resin 7 in the dam portion accommodation area S9 of the dam portion 9 provided on the silicon nitride substrate 11C, the power module 3 does not require a dedicated case and allows the height of the sealing resin 7 to be adjusted relatively easily during manufacturing.

In addition, in the power module 3, the bottom conductor layer 13 of the ceramic substrate 10C is not restricted by the dam portion 9 and the sealing resin 7, which increases the design freedom of the structures formed on the surface of the bottom conductor layer 13, which is the second main surface of the substrate.

Specifically, the fin base 15, which is a heat dissipation fin, can be fixed relatively easily by using a material that can be bonded at room temperature as the heat dissipation sheet 73. Therefore, even after the device is completed, the power module 3 can be relatively easily reworked using the heat dissipation sheet 73 to replace the fin base 15 fixed on the surface of the lower conductor layer 13 with a new fin base. In this way, the power module 3 can be relatively easily provided with heat dissipation fins of various shapes.

In addition, by using a material with relatively high thermal conductivity for the heat dissipation sheet 73 in the power module 3, the heat generated during operation of the semiconductor element 20 can be effectively dissipated to the fin base 15 via the ceramic substrate 10C and the heat dissipation sheet 73.

Furthermore, the lower conductor layer 13 of the ceramic substrate 10C of the power module 3 is not covered with the sealing resin 7 and is open. Therefore, the mounting surface 15s of the fin base 15 can be relatively easily bonded to the surface of the lower conductor layer 13 via the heat dissipation sheet 73, which can be bonded at room temperature.

(Production method)
21 to 25 are explanatory diagrams that show a schematic cross-sectional structure during the manufacturing process of the power module 3. An XYZ orthogonal coordinate system is shown in each of Fig. 21 to Fig. 25. Hereinafter, the manufacturing method of the power module 3 will be described with reference to Fig. 21 to Fig. 25.

As shown in Figures 19 and 20, the power module 3 includes four semiconductor elements 20, four metal blocks 66, and two metal blocks 60, but for convenience of explanation, the structure shown in Figures 21 to 25 will be used as the basis. The process for forming the metal blocks 60, which are not shown in Figures 21 to 25, is the same as the manufacturing method of the first embodiment shown in Figures 4 to 8.

First, a ceramic substrate 10C is prepared as a substrate for the semiconductor device of the third embodiment. In the power module 3, the ceramic substrate 10C and the semiconductor element 20 serve as block mounting members.

Next, as shown in FIG. 21, solder 31 and two semiconductor elements 20 are positioned above the upper conductor layer 12 of the ceramic substrate 10C, and solder 32 and two metal blocks 66 are positioned above the two semiconductor elements 20, and solder bonding is performed using the solder 31 and the solder 32 in a reflow furnace.

As a result, two semiconductor elements 20 are mounted on the surface of the upper conductor layer 12 of the ceramic substrate 10C via solder 31, and two metal blocks 66 are mounted on the upper surfaces of the two semiconductor elements 20 via solder 32. In other words, the metal blocks 66 are joined via solder 32 to the upper surfaces of the semiconductor elements 20 that serve as block mounting members.

Next, as shown in FIG. 22, a plurality of dam materials 81 are laminated on the upper surface of the silicon nitride base material 11C of the ceramic substrate 10C to form the dam portion 9. The dam materials 81 are laminated, for example, by a coating process using a dispenser. The completed dam portion 9 has a dam portion accommodation area S9, and the dam portion 9 is provided on the upper surface of the silicon nitride base material 11 so that the solder 31, the upper surface conductor layer 12, and the two semiconductor elements 20 are present within the dam portion accommodation area S9.

Then, as shown in FIG. 23, the terminal block 51 is adhered and fixed to a portion of the surface of the upper conductor layer 12 of the ceramic substrate 10C. The signal terminal 63 is integrated with the terminal block 51.

After the terminal block 51 is fixed to the upper conductor layer 12, wiring is performed using the wire 41. That is, the surface of the terminal horizontal portion 63a and the semiconductor element 20 are electrically connected by the wire 41. After wiring the wire 41, a circuit is formed that includes the two semiconductor elements 20, the wire 41, the two metal blocks 66, and the signal terminal 63.

Next, as shown in FIG. 24, sealing resin 7 is injected into the dam portion housing area S9 and heated to harden so that the upper surfaces and upper portions of the sides of each of the two metal blocks 66 are exposed. In other words, the upper surfaces and upper portions of the sides of the metal blocks 66 are not covered by the sealing resin 7 and are exposed.

On the other hand, within the dam portion accommodation area S9, the solders 31 and 32, the upper surface conductor layer 12 of the ceramic substrate 10C, the two semiconductor elements 20, and the wires 41 are all covered with the sealing resin 7.

Furthermore, parts of the two metal blocks 66 and parts of the terminal block 51 are covered with sealing resin 7. However, the top surfaces and upper parts of the side surfaces of the two metal blocks 66 are not covered with sealing resin 7 and are exposed. In other words, the side surfaces of the exposed metal blocks 66 include a pair of exposed side surfaces 66s and 66s that face each other in the X direction.

Then, the lower conductor layer 13 of the ceramic substrate 10C and the mounting surface 15s of the fin base 15 are adhesively fixed via the heat dissipation sheet 73.

Finally, as shown in FIG. 25, the screw hole regions 66x of the two metal blocks 66 are positioned so that they match the two openings 62o of one main terminal 67 in a plan view, and the metal blocks 66 and the main terminal 67 are connected and fixed using two screws 61.

The power module 3 of the third embodiment, like the power module 2 of the second embodiment, can fix the main terminal 67 in a state where the metal block 66 is stably restrained by a pair of exposed side surfaces 66s and 66s, so that damage to the solder 31 and the semiconductor element 20 when the main terminal 67 is fixed can be suppressed.

As shown in FIG. 25, the metal block 66 is partially sealed with the sealing resin 7, so when the main terminal 67 is attached to the top surface of the metal block 66 with the two screws 61, the tightening torque of each of the two screws 61 has the effect of reducing damage to the solder 32, which serves as the block bonding material between the metal block 66 and the semiconductor element 20.

The manufacturing method for the power module 3 described above includes the following steps (a) to (f) as a manufacturing method for a semiconductor device having a main terminal 67 for transmitting an external signal.

Step (a) is a step of preparing a ceramic substrate 10C as a substrate having a first and second main surfaces.

Step (b) is a step of mounting a plurality of semiconductor elements 20 on the surface of the upper conductor layer 12, which becomes the "first main surface of the substrate." In the basic aspect of the third embodiment, the ceramic substrate 10C and the semiconductor elements 20 function as block mounting members. Step (b) corresponds to the process described with reference to FIG. 21.

Step (c) is a step of joining the ceramic substrate 10C, which serves as the block mounting member, and the metal block 60 via solder 31, which functions as a block bonding material, and joining the semiconductor element 20, which serves as the block mounting member, and the metal block 66 via solder 32, which functions as a block bonding material. Step (c) corresponds to the process described with reference to FIG. 21.

Step (d) is a step of forming sealing resin 7 to cover ceramic substrate 10C, semiconductor element 20, and solders 31 and 32. Step (d) corresponds to the process described with reference to Figures 22 to 24.

After step (d) is performed, the upper surfaces and upper portions of the sides of the metal blocks 60 and 66 are not covered by the sealing resin 7 and are exposed. Therefore, there are a pair of exposed side surfaces 60s and 60s and a pair of exposed side surfaces 66s and 66s that are exposed by about 2 mm from the sealing resin 7.

Step (d) includes the following steps (d-1) and (d-2).

Step (d-1) is a step of providing a dam portion 9, which is a member for forming a storage space, on the surface of the silicon nitride base material 11C of the ceramic substrate 10C, surrounding the upper surface conductor layer 12, the semiconductor element 20, and the metal blocks 60 and 66 of the ceramic substrate 10C. Step (d-1) corresponds to the process described with reference to FIG. 22.

Step (d-2) is a step of forming sealing resin 7 to cover upper surface conductor layer 12, semiconductor element 20, and solders 31 and 32 within dam portion accommodation area S9, which is an element accommodation space surrounded by dam portion 9. Step (d-2) corresponds to the process described with reference to FIG. 24.

Step (e) is performed after step (d) described above, and is a step of attaching main terminals 62 and 67 to the upper surfaces of metal blocks 60 and 66, respectively. Step (e) corresponds to the process described with reference to FIG. 25.

Step (f) is a step of joining the lower conductor layer 13 and the fin base 15, which is a heat dissipation fin, via the heat dissipation sheet 73. Step (f) corresponds to the process described with reference to FIG. 24.

In the method for manufacturing the power module 3 shown in Figures 21 to 25, steps (d) and (f) are carried out almost simultaneously, and then step (e) is carried out.

In the manufacturing method of the semiconductor device of the third embodiment, since the dam portion 9 is formed by stacking multiple dam materials 81 in step (d-1), the height of the sealing resin 7 formed in the dam portion accommodation area S9 of the dam portion 9 in step (d-2) can be adjusted relatively easily without requiring a dedicated case.

Furthermore, in the method for manufacturing a semiconductor device according to the third embodiment, in step (f), the fin base 15, which is a heat dissipation fin, can be manufactured relatively easily using the heat dissipation sheet 73.

In addition, in the power module 3, which is a semiconductor device manufactured by the manufacturing method of the power module 3, a material with relatively high thermal conductivity can be used as the heat dissipation sheet 73 to fix the mounting surface 15s of the fin base 15 and the surface of the lower conductor layer 13 of the ceramic substrate 10C. Therefore, the power module 3 can effectively dissipate heat generated during operation of the semiconductor element 20 to the fin base 15 via the ceramic substrate 10C and the heat dissipation sheet 73.

In the manufacturing method of the power module 3, solder 31 is used to join the semiconductor element 20 to the upper conductor layer 12, and solder 32 is used to join the semiconductor element 20 to the metal block 66, but instead of the solders 31 and 32, a high-melting-point solder with high heat resistance or a silver sintered material may be used.

When using high melting point solder or silver sintered material, heat dissipation can be improved by using fin base solder with a low melting point instead of the heat dissipation sheet 73 as the joining material between the ceramic substrate 10C and the fin base 15.

In addition, because the metal block 66 is connected to the outside world through the screw hole region 66x, which is the main terminal mounting region, even if the solder 32, whose surface is exposed in the screw hole region 66x, remelts, the increase in volume of the solder 32 is unlikely to cause damage to the sealing resin 7.

<Fourth embodiment>
In the fourth embodiment, the power modules 1, 1B, 1C, 2, 2B, and 3, which are the semiconductor devices according to the first to third embodiments, are applied to a power conversion device. Although the present disclosure is not limited to a specific power conversion device, the following describes the fourth embodiment in the case where the present disclosure is applied to a three-phase inverter.

FIG. 26 is a block diagram showing the configuration of a power conversion system to which a power conversion device according to embodiment 4 of the present disclosure is applied.

The power conversion system shown in FIG. 26 is composed of a power source 1000, a power conversion device 2000, and a load 3000. The power source 1000 is a DC power source, and supplies DC power to the power conversion device 2000. The power source 1000 can be composed of various things, for example, a DC system, a solar cell, or a storage battery, or it may be composed of a rectifier circuit connected to an AC system or an AC/DC converter. The power source 1000 may also be composed of a DC/DC converter that converts the DC power output from the DC system into a specified power.

The power conversion device 2000 is a three-phase inverter connected between the power source 1000 and the load 3000, converts the DC power supplied from the power source 1000 into AC power, and supplies the AC power to the load 3000. As shown in FIG. 26, the power conversion device 2000 includes a main conversion circuit 2001 that converts the DC power into AC power and outputs it, and a control circuit 2003 that outputs a control signal to the main conversion circuit 2001 to control the main conversion circuit 2001.

The load 3000 is a three-phase motor driven by AC power supplied from the power conversion device 2000. Note that the load 3000 is not limited to a specific use, but is a motor mounted on various electrical devices, and is used, for example, as a motor for hybrid cars, electric cars, railroad cars, elevators, or air conditioning equipment.

The power conversion device 2000 will be described in detail below. The main conversion circuit 2001 includes switching elements and free wheel diodes (not shown), and converts DC power supplied from the power source 1000 into AC power by switching the switching elements, and supplies it to the load 3000. There are various specific circuit configurations for the main conversion circuit 2001, but the main conversion circuit 2001 in this embodiment is a two-level three-phase full bridge circuit that can be configured from six switching elements and six free wheel diodes connected in inverse parallel to each switching element. At least one of the switching elements and free wheel diodes of the main conversion circuit 2001 is configured from one of the power modules 1, 1B, 1C, 2, 2B, and 3 used in the above-mentioned embodiments 1 to 3.

The six switching elements are connected in series in pairs to form upper and lower arms, and each upper and lower arm constitutes one phase (U phase, V phase, W phase) of the full bridge circuit. The output terminals of each upper and lower arm, i.e., the three output terminals of the main conversion circuit 2001, are connected to the load 3000.

The main conversion circuit 2001 also includes a drive circuit (not shown) that drives each switching element, but the drive circuit may be built into the semiconductor module 2002, or the drive circuit may be provided separately from the semiconductor module 2002. The semiconductor module 2002 may be configured with the power modules 1, 1B, 1C, 2, 2B, and 3 of the above-mentioned first to third embodiments.

The drive circuit generates drive signals that drive the switching elements of the main conversion circuit 2001 and supplies them to the control electrodes of the switching elements of the main conversion circuit 2001. Specifically, in accordance with a control signal from the control circuit 2003 described below, it outputs to the control electrodes of each switching element a drive signal that turns the switching element on and a drive signal that turns the switching element off. When maintaining a switching element in the on state, the drive signal is a voltage signal (on signal) that is equal to or higher than the threshold voltage of the switching element, and when maintaining a switching element in the off state, the drive signal is a voltage signal (off signal) that is equal to or lower than the threshold voltage of the switching element.

The control circuit 2003 controls the switching elements of the main conversion circuit 2001 so that the desired power is supplied to the load 3000. Specifically, it calculates the time (on time) that each switching element of the main conversion circuit 2001 should be in the on state based on the power to be supplied to the load 3000. For example, the main conversion circuit 2001 can be controlled by PWM control, which modulates the on time of the switching elements according to the voltage to be output. Then, it outputs a control command (control signal) to a drive circuit provided in the main conversion circuit 2001 so that an on signal is output to the switching element that should be in the on state at each point in time, and an off signal is output to the switching element that should be in the off state. The drive circuit outputs an on signal or an off signal as a drive signal to the control electrode of each switching element according to this control signal.

In the power conversion device 2000 of the fourth embodiment, any of the power modules 1, 1B, 1C, 2, 2B, and 3, which are the semiconductor devices of the first to third embodiments, are used as the switching elements and free wheel diodes of the main conversion circuit 2001, thereby improving the yield and performance of the device.

In the fourth embodiment, an example of applying the present disclosure to a two-level three-phase inverter has been described, but the present disclosure is not limited to this and can be applied to various power conversion devices. In the present embodiment, a two-level power conversion device is described, but a three-level or multi-level power conversion device may also be used, and the present disclosure may be applied to a single-phase inverter when supplying power to a single-phase load. Furthermore, the present disclosure can also be applied to a DC/DC converter or an AC/DC converter when supplying power to a DC load, etc.

Furthermore, the power conversion device to which this disclosure is applied is not limited to the case where the load described above is an electric motor, but can also be used, for example, as a power supply device for an electric discharge machine or laser processing machine, or an induction heating cooker or a non-contact power supply system, and can also be used as a power conditioner for a solar power generation system or a power storage system, etc.

In addition, within the scope of this disclosure, it is possible to freely combine the various embodiments, modify them as appropriate, or omit them.

Although the present disclosure has been described in detail, the above description is illustrative in all respects and does not limit the present disclosure. It is understood that countless variations not illustrated can be envisioned without departing from the scope of the present disclosure.

The various aspects of this disclosure are summarized below as appendices.

(Appendix 1)
A semiconductor device having a main terminal for transmitting an external signal,
a substrate having first and second major surfaces;
A semiconductor element provided on a first main surface of the substrate;
a metal block provided on a block mounting member which is at least one of the substrate and the semiconductor element;
The block mounting member and the metal block are joined via a block joining material,
the metal block has a main terminal attachment region, the main terminal is fixed to the metal block at the main terminal attachment region,
The semiconductor device includes:
The block mounting member and the block bonding material are covered with a sealing resin provided on the first main surface of the substrate.
Semiconductor device.

(Appendix 2)
2. The semiconductor device according to claim 1,
the main terminal attachment region includes an upper surface of the metal block, and the main terminal is fixed onto the upper surface of the metal block;
The upper surface of the metal block is not covered with the sealing resin and is exposed.
Semiconductor device.

(Appendix 3)
3. The semiconductor device according to claim 1,
The main terminal has an opening,
The metal block has a screw hole region extending from an upper surface to a lower surface,
the main terminal mounting area includes the screw hole area,
The semiconductor device includes:
The main terminal is fixed on the upper surface of the metal block in an attachment manner by inserting the screw portion into the opening and the screw hole region of the main terminal, further comprising a screw having a head and a screw portion.
Semiconductor device.

(Appendix 4)
A semiconductor device according to any one of claims 1 to 3,
the substrate includes an insulating substrate, the insulating substrate having an insulating base material, an upper conductor layer provided on an upper surface of the insulating base material, and a lower conductor layer provided on a lower surface of the insulating base material, a surface of the upper conductor layer being a first main surface of the substrate, and a surface of the lower conductor layer being a second main surface of the substrate,
The thickness of the metal block in the height direction is greater than the thickness of the upper surface conductor layer.
Semiconductor device.

(Appendix 5)
A semiconductor device according to any one of claims 1 to 4,
a housing space forming member having an element housing space for housing the substrate, the semiconductor element, and the metal block therein;
The sealing resin is provided in the element accommodating space.
Semiconductor device.

(Appendix 6)
6. The semiconductor device according to claim 5,
Further comprising a heat dissipation fin provided on the second main surface side of the substrate,
the heat dissipation fin has a planar mounting surface that is wider than the substrate,
the storage space forming member is provided on the mounting surface of the heat dissipation fin,
Semiconductor device.

(Appendix 7)
7. The semiconductor device according to claim 6,
the accommodation space forming member includes a case having a case accommodation space, and the element accommodation space includes the case accommodation space;
Semiconductor device.

(Appendix 8)
8. The semiconductor device according to claim 7,
the case includes a main terminal case connected to the main terminal such that the main terminal protrudes from the case receiving space to the outside,
The sealing resin is provided to cover all of the substrate, the semiconductor element, the metal block, and the main terminals present in the case housing space.
Semiconductor device.

(Appendix 9)
7. The semiconductor device according to claim 6,
The storage space forming member includes a dam portion,
A space surrounded by the dam portion is a dam portion accommodating region, and the element accommodating space includes the dam portion accommodating region,
The dam portion is composed of a laminated structure of multiple dam materials.
Semiconductor device.

(Appendix 10)
5. The semiconductor device according to claim 4,
a dam portion provided to surround the upper surface conductor layer of the insulating substrate, the semiconductor element, and the metal block;
the dam portion is provided on the insulating base material of the insulating substrate,
The space surrounded by the dam portion becomes a dam portion accommodation area,
The dam portion is formed of a laminated structure of a plurality of dam materials,
The sealing resin is provided in the dam portion accommodation region of the dam portion.
Semiconductor device.

(Appendix 11)
11. The semiconductor device according to claim 10,
The insulating substrate further includes a heat dissipation fin fixed to the surface of the lower conductor layer via a heat dissipation sheet.
Semiconductor device.

(Appendix 12)
A method for manufacturing a semiconductor device having a main terminal for transmitting an external signal, comprising the steps of:
(a) providing a substrate having first and second major surfaces;
(b) mounting a semiconductor element on a first main surface of the substrate, wherein at least one of the substrate and the semiconductor element serves as a block mounting member;
(c) joining the block mounting member and a metal block via a block joining material;
(d) forming a sealing resin to cover at least the block mounting member and the block bonding material, and an upper surface of the metal block is not covered with the sealing resin and is exposed;
(e) performing the step after (d), further comprising the step of attaching the main terminal onto an upper surface of the metal block;
A method for manufacturing a semiconductor device.

(Appendix 13)
13. A method for manufacturing a semiconductor device according to claim 12, comprising:
The step (d)
(d-1) providing a storage space forming member surrounding the substrate, the semiconductor element, and the metal block;
(d-2) forming the sealing resin to cover at least the block mounting member and the block bonding material within the element accommodating space, which is a space surrounded by the accommodating space forming member;
A method for manufacturing a semiconductor device.

(Appendix 14)
13. A method for manufacturing a semiconductor device according to claim 12, comprising:
the substrate includes an insulating substrate, the insulating substrate having an insulating base material, an upper conductor layer provided on an upper surface of the insulating base material, and a lower conductor layer provided on a lower surface of the insulating base material;
The step (b)
(b-1) a step of mounting the semiconductor element on the upper surface conductor layer of the insulating substrate, at least one of the insulating substrate having the upper surface conductor layer and the semiconductor element becomes the block mounting member;
The step (d)
(d-1) stacking a plurality of dam materials on the insulating base material around the semiconductor element and the metal block to provide a dam portion;
(d-2) forming the sealing resin in a dam portion accommodation area, which is a space surrounded by the dam portion, to cover at least the block mounting member and the block bonding material;
The method for manufacturing a semiconductor device includes:
(f) further comprising a step of joining the lower conductor layer and a heat dissipation fin via a heat dissipation sheet;
A method for manufacturing a semiconductor device.

(Appendix 15)
A main conversion circuit having the semiconductor device according to any one of claims 1 to 11, which converts input power and outputs the converted power;
a control circuit for outputting a control signal for controlling the main conversion circuit to the main conversion circuit,
Power conversion equipment.

1, 1B, 1C, 2, 2B, 3 Power module, 5 Case, 5T Case with main terminal, 7, 7B, 72 Sealing resin, 8, 9 Dam section, 10, 10B, 10C Ceramic substrate, 11, 11B, 11C Silicon nitride substrate, 12 Upper conductor layer, 13 Lower conductor layer, 15, 15B Fin base, 20 Semiconductor element, 41-43 Wire, 51 Terminal block, 60, 66 Metal block, 61 Screw, 62, 67 Main terminal, 63 Signal terminal, 64 Pin terminal, 81 Dam material, 1000 Power source, 2000 Power conversion device, 2001 Main conversion circuit, 2002 Semiconductor module, 2003 Control circuit, 3000 Load.

Claims (16)

A semiconductor device having a main terminal for transmitting an external signal,
a substrate having first and second major surfaces;
A semiconductor element provided on a first main surface of the substrate;
a metal block provided on a block mounting member which is at least one of the substrate and the semiconductor element;
The block mounting member and the metal block are joined via a block joining material,
the metal block has a main terminal attachment region, the main terminal is fixed to the metal block at the main terminal attachment region,
The semiconductor device includes:
The block mounting member and the block bonding material are covered with a sealing resin provided on the first main surface of the substrate.
Semiconductor device. 2. The semiconductor device according to claim 1,
the main terminal attachment region includes an upper surface of the metal block, and the main terminal is fixed onto the upper surface of the metal block;
The upper surface of the metal block is not covered with the sealing resin and is exposed.
Semiconductor device. 3. The semiconductor device according to claim 2,
The main terminal has an opening,
The metal block has a screw hole region extending from an upper surface to a lower surface,
the main terminal mounting area includes the screw hole area,
The semiconductor device includes:
The main terminal is fixed on the upper surface of the metal block in an attachment manner by inserting the screw portion into the opening and the screw hole region of the main terminal, further comprising a screw having a head and a screw portion.
Semiconductor device. 4. The semiconductor device according to claim 3,
an upper part of a side surface of the metal block is not covered with the sealing resin and is exposed;
The exposed side surface of the metal block includes a pair of opposing exposed side surfaces.
Semiconductor device. 5. The semiconductor device according to claim 1,
the substrate includes an insulating substrate, the insulating substrate having an insulating base material, an upper conductor layer provided on an upper surface of the insulating base material, and a lower conductor layer provided on a lower surface of the insulating base material, a surface of the upper conductor layer being a first main surface of the substrate, and a surface of the lower conductor layer being a second main surface of the substrate,
The thickness of the metal block in the height direction is greater than the thickness of the upper surface conductor layer.
Semiconductor device. 6. The semiconductor device according to claim 1,
a housing space forming member having an element housing space for housing the substrate, the semiconductor element, and the metal block therein;
The sealing resin is provided in the element accommodating space.
Semiconductor device. 7. The semiconductor device according to claim 6,
Further, a heat dissipation fin is provided on the second main surface side of the substrate,
the heat dissipation fin has a planar mounting surface that is wider than the substrate,
the storage space forming member is provided on the mounting surface of the heat dissipation fin,
Semiconductor device. 8. The semiconductor device according to claim 7,
the accommodation space forming member includes a case having a case accommodation space, and the element accommodation space includes the case accommodation space;
Semiconductor device. 9. The semiconductor device according to claim 8,
the case includes a main terminal case connected to the main terminal such that the main terminal protrudes from the case receiving space to the outside,
The sealing resin is provided to cover all of the substrate, the semiconductor element, the metal block, and the main terminals present in the case housing space.
Semiconductor device. 8. The semiconductor device according to claim 7,
The storage space forming member includes a dam portion,
A space surrounded by the dam portion is a dam portion accommodating region, and the element accommodating space includes the dam portion accommodating region,
The dam portion is composed of a laminated structure of multiple dam materials.
Semiconductor device. 6. The semiconductor device according to claim 5,
a dam portion provided to surround the upper surface conductor layer of the insulating substrate, the semiconductor element, and the metal block;
the dam portion is provided on the insulating base material of the insulating substrate,
The space surrounded by the dam portion becomes a dam portion accommodation area,
The dam portion is formed of a laminated structure of a plurality of dam materials,
The sealing resin is provided in the dam portion accommodation region of the dam portion.
Semiconductor device. 12. The semiconductor device according to claim 11,
The insulating substrate further includes a heat dissipation fin fixed to the surface of the lower conductor layer via a heat dissipation sheet.
Semiconductor device. A method for manufacturing a semiconductor device having a main terminal for transmitting an external signal, comprising the steps of:
(a) providing a substrate having first and second major surfaces;
(b) mounting a semiconductor element on a first main surface of the substrate, wherein at least one of the substrate and the semiconductor element serves as a block mounting member;
(c) joining the block mounting member and a metal block via a block joining material;
(d) forming a sealing resin to cover at least the block mounting member and the block bonding material, wherein an upper surface and an upper portion of a side surface of the metal block are not covered with the sealing resin and are exposed, and the exposed side surfaces of the metal block include a pair of opposing exposed side surfaces;
(e) performing the step after (d), further comprising the step of attaching the main terminal onto an upper surface of the metal block;
A method for manufacturing a semiconductor device. 14. The method of manufacturing a semiconductor device according to claim 13,
The step (d)
(d-1) providing a storage space forming member surrounding the substrate, the semiconductor element, and the metal block;
(d-2) forming the sealing resin to cover at least the block mounting member and the block bonding material within the element accommodating space, which is a space surrounded by the accommodating space forming member;
A method for manufacturing a semiconductor device. 14. The method of manufacturing a semiconductor device according to claim 13,
the substrate includes an insulating substrate, the insulating substrate having an insulating base material, an upper conductor layer provided on an upper surface of the insulating base material, and a lower conductor layer provided on a lower surface of the insulating base material;
The step (b)
(b-1) a step of mounting the semiconductor element on the upper surface conductor layer of the insulating substrate, at least one of the insulating substrate having the upper surface conductor layer and the semiconductor element becomes the block mounting member;
The step (d)
(d-1) stacking a plurality of dam materials on the insulating base material around the semiconductor element and the metal block to provide a dam portion;
(d-2) forming the sealing resin in a dam portion accommodation area, which is a space surrounded by the dam portion, to cover at least the block mounting member and the block bonding material;
The method for manufacturing a semiconductor device includes:
(f) further comprising a step of joining the lower conductor layer and a heat dissipation fin via a heat dissipation sheet;
A method for manufacturing a semiconductor device. A main conversion circuit having the semiconductor device according to any one of claims 1 to 12, which converts input power and outputs the converted power;
a control circuit for outputting a control signal for controlling the main conversion circuit to the main conversion circuit,
Power conversion equipment.

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