Semiconductor module, semiconductor device, and vehicle

Abstract

The present invention reduces uneven filling of encapsulant in a semiconductor module using a case with an integrated lid. A semiconductor module (2) includes: a case (210) covering a circuit board (4) mounted on a base (200), the case including sides (211) surrounding the perimeter of the circuit board and a lid (212) located above the circuit board; a plurality of conductor plates (6A-6D), each being electrically connected to a conductor pattern on the circuit board and extending out of the case through a slit (220) provided in the case; and encapsulants (701, 702) encapsulating the circuit board, wherein the case has partitions (214, 215) which are placed in the area enclosed by the lid, the sides, and the circuit board and which are placed between the plurality of conductor plates to insulate the plurality of conductor plates from one another, and the partitions have notched sections (216, 217) at positions that do not overlap with the plurality of conductor plates, thereby making the height of the portion that does not overlap with the plurality of conductor plates lower than the height of the portion that does overlap.

Description

[Technical Field]

[0001] The present invention relates to a semiconductor module, a semiconductor device, and a vehicle. [Background technology]

[0002] BACKGROUND ART Semiconductor modules used in power conversion devices such as inverter devices include semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors), power MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), and FWDs (Free Wheeling Diodes).

[0003] In this type of semiconductor module, a circuit board having circuit components such as semiconductor elements mounted on a wiring board is housed in a case, and then the case is filled with a sealing material to seal the circuit board.

[0004] In addition, in this type of semiconductor module, various measures are taken to prevent, for example, corrosion of circuit components such as semiconductor elements and wiring members on the circuit board due to corrosive gases, and deterioration of insulation due to dust, moisture, etc.

[0005] For example, Patent Document 1 describes a power conversion device that includes a power circuit module in which a power circuit board on which a power semiconductor is mounted is sealed with insulating resin with its lead terminals extended to the outside, and a control circuit module in which a control circuit board for driving and controlling the power semiconductor is embedded with insulating resin with its connection parts exposed to the outside, and in which the lead terminals of the power circuit module are attached to the connection parts of the control circuit module, electrically connected, and mechanically integrated.

[0006] Furthermore, for example, Patent Document 2 describes a semiconductor device in which an epoxy resin is further filled on the upper surface side of the silicone gel that seals the power device and control circuit inside the case. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-121861 [Patent Document 2] Japanese Patent Application Publication No. 7-335800 Summary of the Invention [Problem to be solved by the invention]

[0008] Some cases for the semiconductor modules described above have a side portion that surrounds the circuit components, such as semiconductor elements, mounted on the circuit board, and a lid portion that serves as a lid above the circuit board, and the lid portion is provided with an injection hole for injecting a sealant. When using such a case, after placing the case over the circuit board, sealant is injected through the injection hole to seal the circuit components, etc., on the circuit board.

[0009] Some semiconductor modules that use a case with a lid ensure insulation between terminals by dividing the space that houses the circuit components into two or more spaces using protruding parts such as partitions or beams provided on the surface of the case facing the space that houses the circuit components and by using a sealant injected through an injection hole.However, in such semiconductor modules, after the space that houses the circuit components is divided into two or more spaces by injecting the sealant, it is difficult to inject additional sealant through the injection hole to evenly fill each of the divided spaces, for example, to prevent corrosion due to corrosive gases.

[0010] In one aspect, the present invention aims to reduce unevenness in filling of a sealing material in a semiconductor module that uses a case with an integrated lid. [Means for solving the problem]

[0011] A semiconductor module according to one embodiment includes a base on which a circuit board is mounted, a case covering the circuit board mounted on the base, the case having a side portion surrounding the outer periphery of the circuit board and a lid portion located above the circuit board, a plurality of conductor plates each electrically connected to a conductor pattern of the circuit board and extending to the outside of the case through a slit provided in the case, and a sealing material that seals the circuit board, wherein the case is arranged in an area surrounded by the lid portion, the side portion, and the circuit board, and has partition portions arranged between the plurality of conductor plates to provide insulation between the plurality of conductor plates, and the partition portions have cutout sections at positions that do not overlap with the plurality of conductor plates when viewed from a direction perpendicular to a plane in which the plurality of conductor plates and the partition portions each extend parallel, so that the height of a second portion where the plurality of conductor plates do not overlap is lower than the height of a first portion that overlaps with the plurality of conductor plates. [Effects of the Invention]

[0012] According to the above-described aspect, it is possible to reduce unevenness in filling of the sealing material in a semiconductor module that uses a case with an integrated lid portion. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a plan view illustrating a configuration example of a semiconductor device according to an embodiment. [Figure 2] 2 is a plan view of the semiconductor device of FIG. 1 with the case omitted. [Figure 3] 2 is a side cross-sectional view for explaining a configuration example of a semiconductor device when viewed from the position of line AA' in FIG. 1 toward the positive side in the Y direction. FIG. [Figure 4] 2 is a side cross-sectional view for explaining a configuration example of a semiconductor module when viewed from the position of line BB' in FIG. 1 toward the positive side in the X direction. FIG. [Figure 5] FIG. 5 is an enlarged view of a region R in FIG. [Figure 6] 10 is a side cross-sectional view illustrating an example of the configuration of the periphery of a lid portion of a case in a completed semiconductor device. FIG. [Figure 7]2 is an equivalent circuit diagram for one phase in the semiconductor device of FIG. 1. FIG. [Figure 8] 10 is a side cross-sectional view of a step of injecting a first sealing material in the manufacturing process of the semiconductor module according to the embodiment. FIG. [Figure 9] 10 is a side cross-sectional view of a step of injecting a second sealing material in the manufacturing process of the semiconductor module according to the embodiment. FIG. [Figure 10] FIG. 10 is a diagram schematically illustrating the flow of the second sealing material in the step of injecting the second sealing material. [Figure 11] 10 is a side cross-sectional view showing a step of injecting a first sealing material in a manufacturing process of a semiconductor module in which a partition portion does not have a notched section. FIG. [Figure 12] 10 is a side cross-sectional view showing a step of injecting a second sealing material in a manufacturing process of a semiconductor module in which the partition portion does not have a cutout section. FIG. [Figure 13] FIG. 10 is a perspective view illustrating a first modified example of a cutout section provided in a partition portion. [Figure 14] FIG. 10 is a side cross-sectional view illustrating a second modified example of a cutout section provided in a partition portion. [Figure 15] FIG. 10 is a perspective view illustrating a third modified example of a cutout section provided in a partition portion. [Figure 16] FIG. 10 is a perspective view illustrating a fourth modified example of a cutout section provided in a partition portion. [Figure 17] 1 is a schematic plan view showing an example of a vehicle to which a semiconductor device according to the present invention is applied; DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, with reference to the drawings, embodiments of a semiconductor module and a semiconductor device to which the present invention can be applied will be described. In this specification and claims, the term "semiconductor module" refers to a device in which a circuit board, which includes circuit components such as semiconductor elements mounted on a wiring board, is housed in a case, and the case is then filled with a sealant to seal the circuit board. In this specification and claims, the term "semiconductor device" refers to a device that includes at least one semiconductor module and components other than the semiconductor module (e.g., a cooler) and integrates them. The X, Y, and Z directions shown in the drawings correspond to the longitudinal, lateral, and height directions of the semiconductor module, respectively. The X, Y, and Z axes shown in the drawings are perpendicular to each other and form a right-handed system. In the following description, the Z direction may be referred to as the up-down direction.

[0015] In the following description of this specification, for example, the end face on the negative side in the Z direction of the illustrated components will be referred to as the bottom face, and the end face on the opposite side (i.e., the positive side in the Z direction) will be referred to as the top face. Also, in this specification, a plan view means the top or bottom face of the semiconductor module as seen from the Z direction.

[0016] The semiconductor module exemplified in the following description may be applied to a power conversion device such as an inverter device for an industrial or automotive motor. The configuration of the semiconductor module shown in the drawings referenced in the following description is simplified to the extent that it does not hinder the understanding of the present invention by those skilled in the art and does not necessarily correspond to the configuration of an actual semiconductor module. Furthermore, the aspect ratios and the size relationships between components in each drawing are merely shown schematically or diagrammatically and do not necessarily correspond to the relationships in an actual semiconductor module. For the sake of convenience, it is anticipated that the size relationships between components may be exaggerated. Furthermore, in the following description with reference to the drawings, detailed descriptions of well-known configurations, functions, operations, and manufacturing methods of semiconductor modules will be omitted to the extent that they do not hinder the understanding of the present invention by those skilled in the art.

[0017] FIG. 1 is a plan view illustrating an example of the configuration of a semiconductor device according to one embodiment. FIG. 2 is a plan view of the semiconductor device of FIG. 1 , with the case omitted. FIG. 3 is a side cross-sectional view illustrating an example of the configuration of a semiconductor device when viewed from the Y-direction positive side along line A-A' in FIG. 1. FIG. 4 is a side cross-sectional view illustrating an example of the configuration of a semiconductor module when viewed from the X-direction positive side along line B-B' in FIG. 1. FIG. 5 is an enlarged view of region R in FIG. 4. FIG. 6 is a side cross-sectional view illustrating an example of the configuration of the periphery of a case lid in a completed semiconductor device. FIG. 7 is an equivalent circuit diagram for one phase of a circuit board in the semiconductor device of FIG. 1. Note that FIGS. 1 to 5 illustrate a state during the manufacturing process of a semiconductor module in the semiconductor device according to this embodiment, more specifically, a state after the case has been attached to a base on which a circuit board is mounted and before a sealant has been injected into the case.

[0018] The semiconductor device 1 illustrated in FIGS. 1 to 5 includes a semiconductor module 2 and a cooler 3 arranged on the underside of the semiconductor module 2. The cooler 3 dissipates heat from the semiconductor module 2 to the outside and has an overall rectangular parallelepiped shape. Although not specifically shown, the cooler 3 is configured by providing a plurality of fins on the underside of a base portion and housing these fins in a water jacket. Note that the configuration of the cooler 3 is not limited to this and can be modified as appropriate.

[0019] The semiconductor module 2 includes a base 200 on which a circuit board 4 and the like are mounted, a case 210 that covers the circuit board 4 and the like mounted on the base 200, conductive plates 6A to 6D that are electrically connected to the conductive pattern of the circuit board 4 mounted on the base 200 and extend to the outside of the semiconductor module 2 through a slit 220 provided in the case 210, and a sealing material (not shown).

[0020] The base 200 is a plate-like member that mounts the circuit board 4, which has circuit components such as semiconductor elements mounted thereon, and other wiring boards connected to the circuit board 4, and that conducts heat generated by the circuit board 4 to the cooler 3. The wiring board in the circuit board 4 is formed, for example, of a direct copper bonding (DCB) substrate, an active metal brazing (AMB) substrate, or a metal-based substrate. The semiconductor elements mounted on the wiring board may be, for example, a combination of one or more switching elements such as an insulated gate bipolar transistor (IGBT) or a power metal oxide semiconductor field effect transistor (MOSFET), and one or more diode elements such as a free wheeling diode (FWD). The semiconductor elements may be, for example, reverse conducting (RC) IGBT elements that combine the functions of an IGBT element and an FWD element. The semiconductor elements may be, for example, reverse blocking (RB) IGBT elements that have sufficient reverse bias voltage resistance. The semiconductor elements mounted on the wiring board may include elements other than the switching elements and diode elements.

[0021] 2 illustrates six circuit boards 4, the number of mounted circuit boards 4 is not limited to this. Furthermore, the conductor patterns of the wiring boards on the circuit boards 4, the mounting positions of the semiconductor elements, the number of mounted semiconductor elements, etc. are not limited to those illustrated.

[0022] The conductive plates 6A to 6D are used as external terminals of the semiconductor module 2, and are formed from metal plates such as copper plates. The conductive plates 6A to 6D may also be called leads, lead frames, bus bars, or the like.

[0023] The first conductor plate 6A, the second conductor plate 6B, and the third conductor plate 6C are used as, for example, the output terminal OUT, the N terminal (input terminal) IN(N), and the P terminal (input terminal) IN(P) in the circuit of the circuit board 4 shown in Fig. 6. The switching element 401a and the diode element 401b connected between the first conductor plate 6A and the second conductor plate 6B, and the switching element 402a and the diode element 402b connected between the first conductor plate 6A and the third conductor plate 6C may each be separate semiconductor elements or may be included in a single semiconductor element. The gates of the switching elements 401a and 402a are each connected to the fourth conductor plate 6D via a control circuit (not shown).

[0024] The first conductor plate 6A, the second conductor plate 6B, and the third conductor plate 6C each include a flat base 601 and a first terminal portion 602 and a second terminal portion 603 protruding from the base 601. The first terminal portion 602 of the first conductor plate 6A is electrically connected to the conductor pattern of the circuit board 4 (wiring board) that serves as the output terminal of the circuit described above with reference to FIG. 6. The first terminal portion 602 of the second conductor plate 6B is electrically connected to the collector of the switching element via the conductor pattern of the circuit board 4. The third conductor plate 6C is electrically connected to the emitter of the switching element via the conductor pattern of the circuit board 4. The first terminal portions 602 of the first conductor plate 6A, the second conductor plate 6B, and the third conductor plate 6C are bent so that the main plane of the base portion 601 of each of the conductor plates 6A to 6C is parallel to the ZX plane when connected (joined) to the conductor pattern of the circuit board 4.

[0025] The second terminal portions 603 of the first conductive plate 6A, the second conductive plate 6B, and the third conductive plate 6C each extend to the outside of the semiconductor module 2 through a slit 220 in the case 210. The second terminal portions 603 of the first conductive plate 6A, the second conductive plate 6B, and the third conductive plate 6C in the process of manufacture illustrated in FIGS. 2 to 4 each extend in the direction of extension of the main plane of the base portion 601 (positive side in the Z direction). However, in the completed semiconductor device 1, for example, as shown in FIG. 7, the portion of each second terminal portion 603 extending to the outside of the semiconductor module 2 is bent so as to fit along the top surface of the case 210. A nut fitting portion 230 into which a nut 10 is fitted is provided at a portion of the top surface of the case 210 that overlaps with the bent second terminal portion 603. The lower end (bottom surface) of the nut fitting portion 230 is provided with a recess 231 that receives the shaft of the bolt 11 used in combination with the nut 10. In the case 210 illustrated in Figures 1 and 3, a total of six nut fitting portions 230 are formed: two in an area overlapping one second terminal portion 603 of the first conductive plate 6A, one in each area overlapping each two second terminal portions 603 of the second conductive plate 6B, and one in each area overlapping each two second terminal portions 603 of the third conductive plate 6C. In addition, openings 603a that overlap with holes in the nut 10 when bent are formed in the second terminal portions 603 of the first conductive plate 6A, the second conductive plate 6B, and the third conductive plate 6C. In such a semiconductor device 1, the shaft of the bolt 11 can be threaded into the hole of the nut 10 to fasten the nut 10, thereby connecting the terminal of the wiring to the second terminal portion 603 of each of the conductor plates 6A, 6B, 6C. In the case 210 of the semiconductor device 1 exemplified in this embodiment, an injection hole 213 for injecting a sealant into the case 210 is provided in the bottom surface of one of the six nut fitting portions 230.

[0026] Each of the plurality of fourth conductive plates 6D includes, for example, a first terminal portion 602 connected to a control circuit and a second terminal portion 603 extending to the outside of the semiconductor module 2 through the slit 220 of the case 210. The second terminal portions 603 of the fourth conductive plates 6D in the process of manufacture illustrated in FIGS. 2 to 4 each extend in the direction of extension of the main plane of the base portion 601 (positive side in the Z direction). However, in the completed semiconductor device 1, the second terminal portions 603 of the fourth conductive plate 6D as well, like the second terminal portions 603 of the other conductive plates 6A, 6B, and 6C described above with reference to FIG. 7, the portions of the second terminal portions 603 extending to the outside of the semiconductor module 2, of the second terminal portions 603 are bent so as to fit along the upper surface of the case 210. In addition, a nut fitting portion (not shown) similar to the nut fitting portion 230 described above with reference to Figure 7 is provided on the upper surface of the case 210 in an area that overlaps with the bent second terminal portion 603 of the fourth conductive plate 6D.

[0027] Case 210 is formed by integrating side surface portion 211 that surrounds the outer periphery of circuit board 4 in a plan view to be filled with a sealing material, and a portion (lid portion 212) that serves as a lid above circuit board 4, and lid portion 212 is provided with injection hole 213 for injecting the sealing material. As described above, injection hole 213 is formed, for example, in the bottom surface of nut fitting portion 230 in a region that overlaps with one bent second terminal portion 603 of third conductor plate 6C.

[0028] A first partition 214 that insulates the conductor plates between the base 601 of the first conductor plate 6A and the base 601 of the second conductor plate 6B, and a second partition 215 that insulates the conductor plates between the second conductor plate 6B and the third conductor plate 6C are provided on the surface of the lid 212 of the case 210 facing the space that accommodates the circuit board 4 and the like (hereinafter referred to as the "inner surface"). The first partition 214 extends along the main plane of the base 601 of the first conductor plate 6A that faces the base 601 of the second conductor plate 6B. The second partition 215 extends along the main plane of the base 601 of the second conductor plate 6B that faces the base 601 of the third conductor plate 6C. The main plane of the base 601 of the conductive plates 6A, 6B, 6C is a plane on which the plurality of conductive plates 6A, 6B, 6C and the partition portions 214, 215 extend in parallel.

[0029] The first partition 214 and the second partition 215 function as ribs to increase the strength of the case 210 and prevent deformation of the case 210 due to warping or twisting. For example, as illustrated in Fig. 3, the end of the first partition 214 in the X direction is connected to the inner surface of the side surface 211 of the case 210. Although not shown, the end of the second partition 215 in the X direction is also connected to the inner surface of the side surface 211 of the case 210.

[0030] The dimensions (heights) from the inner surfaces of first partition portion 214 and second partition portion 215 to their lower ends (ends on the negative side in the Z direction) are set, for example, so that the space (hereinafter referred to as the "accommodation space") that comes into contact with the sealing material injected through injection hole 213 and accommodates circuit board 4 and the like in case 210 is separated into three spaces. That is, as illustrated in FIGS. 4 and 5, an upper surface 700 of the sealing material injected through injection hole 213 is higher than the lower ends of first partition portion 214 and second partition portion 215. In the following description, the space between first partition portion 214 and second partition portion 215 will be referred to as the first space, the space separated from the first space by first partition portion 214 will be referred to as the second space, and the space separated from the first space by second partition portion 215 will be referred to as the third space. 1 to 5, a portion of lid portion 212 defining the first space is provided with injection hole 213 and slit 220 through which second terminal portion 603 of second conductive plate 6B passes. A portion of lid portion 212 defining the second space is provided with slit 220 through which second terminal portion 603 of first conductive plate 6A passes, and slit 220 through which second terminal portion 603 of fourth conductive plate 6D passes. A portion of lid portion 212 defining the third space is provided with slit 220 through which second terminal portion 603 of third conductive plate 6C passes, and slit 220 through which second terminal portion 603 of fourth conductive plate 6D passes.

[0031] 3 to 5, the case 210 in the semiconductor module 2 of this embodiment is provided with a cutout section 216 whose lower end is displaced toward the inner surface at a portion of the first partition section 214 that is outside the portion along the base 601 of the first conductive plate 6A (the portion overlapping with the base 601). Similarly, the case 210 is provided with a cutout section 217 whose lower end is displaced toward the inner surface at a portion of the second partition section 215 that is outside the portion along the base 601 of the second conductive plate 6B (the portion overlapping with the base 601). In other words, the partitions 214, 215 have cutout sections 216, 217 at positions where they do not overlap with the plurality of conductive plates when viewed from a direction (Y direction in the figure) perpendicular to a plane (ZX plane in the figure) along which the plurality of conductive plates 6A, 6B, 6C and the partitions 214, 215 extend in parallel, so that the height of the portion (second portion) where the plurality of conductive plates do not overlap is lower than the height of the portion (first portion) where the plurality of conductive plates overlap. In other words, because the partitions 214, 215 have cutout sections 216, 217, the distance from the lower end of the second portion of the partitions 214, 215 where the plurality of conductive plates do not overlap to the base 200 is longer than the distance from the lower end of the first portion that overlaps with the plurality of conductive plates.

[0032] When sealing material is injected through injection hole 213 to seal circuit board 4 and the like during the manufacturing process of semiconductor module 2 of this embodiment, the first space and the second space communicate with each other via a through hole formed by upper surface 700 of the sealing material and notched section 216 of first partition section 214. Similarly, the first space and the third space communicate with each other via a through hole formed by upper surface 700 of the sealing material and notched section 217 of second partition section 215. Such a through hole that communicates the two spaces is formed outside the portion that overlaps with base portion 601 of the conductor plate, and therefore does not affect the insulation between the conductor plates.

[0033] The above-described case 210 is formed by injection molding using an insulating material that has high heat resistance, dimensional stability, and low moisture absorption, such as PPS (Poly Phenylene Sulfide) or PA (Poly Amide). The case 210 formed by injection molding has a side portion 211, a lid portion 212, a first partition portion 214, and a second partition portion 215 that are integrally formed. Note that, in the process of sealing the circuit board 4 and the like with a sealing material, the side portion 211 and the lid portion 212 having the injection hole 213 are integrated into one piece, and the case 210 is provided with the first partition portion 214 having the cutout section 216 and the second partition portion 215 having the cutout section 217. Therefore, the method for forming the case 210 is not limited to a specific method.

[0034] 8 is a side cross-sectional view of a step of injecting a first sealing material in a manufacturing process of a semiconductor module according to this embodiment. FIG. 9 is a side cross-sectional view of a step of injecting a second sealing material in a manufacturing process of a semiconductor module according to this embodiment. FIG. 10 is a diagram schematically showing the flow of the second sealing material in the step of injecting the second sealing material. The ranges shown in FIGS. 8 and 9 each correspond to region R in FIG. 4. FIG. 10 corresponds to a view looking downward (negative side in the Z direction) from position C in FIG. 5.

[0035] In the manufacturing process (assembly process) of the semiconductor module 2 of this embodiment, first, the circuit board 4 and other wiring boards are mounted on the base 200, and then conductor plates 6A to 6D are connected to the conductor patterns of the circuit board 4. Thereafter, a case 210 having a lid 212 is attached to the base 200 so as to cover the circuit board 4. The base 200 and the case 210 are attached, for example, by fastening (screwing) screws into screw holes in the case 210 that overlap round holes in the base 200. At this time, the interior of the housing space of the case 210 is still a single space, as illustrated in FIG. 5.

[0036] Next, as shown in FIG. 8 , a first sealing step is performed in which a first sealant 701 is injected through an injection hole 213 provided in the lid 212 of the case 210 to seal the circuit board 4 and the like. Silicone gel, for example, can be used as the first sealant 701. The materials used in the step of injecting silicone gel as the first sealant 701 to seal the circuit board 4 and the like, as well as the processing during and after injection, are well known, and therefore detailed explanations will be omitted in this specification. The amount of first sealant 701 injected is adjusted, for example, so that the upper surface 700 after the first sealing step is above the lower ends of the first partition portion 214 and the second partition portion 215 and below the lower ends of the cutout sections 216 and 217. After the first sealing process is completed, the storage space of the case 210 is divided into a first space, a second space connected to the first space by a through hole formed at the position of the cutout section 216, and a third space connected to the first space by a through hole formed at the position of the cutout section 217.

[0037] Next, as shown in FIG. 9 , a second sealing step is performed in which a second sealing material 702 (additional sealing material) is injected through an injection hole 213 provided in the lid 212 of the case 210. The second sealing material 702 may be, for example, an insulating material (e.g., epoxy resin) that prevents corrosive gases such as hydrogen sulfide or moisture from penetrating the first sealing material 701 (e.g., silicone gel) and corroding the circuit components of the circuit board 4. The first sealing material 701 and the second sealing material 702 are not limited to a specific combination. For example, the first sealing material 701 and the second sealing material 702 may be a combination of insulating materials that exhibit the same type of function, or a combination of insulating materials that have the same composition.

[0038] In the second sealing step, the portion of first partition 214 along base 601 of first conductor plate 6A and the portion of second partition 215 along base 601 of second conductor plate 6B each have their lower ends buried in first sealing material 701. Therefore, second sealing material 702 injected from injection hole 213 located between first partition 214 and second partition 215 flows in the positive and negative directions in the X direction along the upper surface of first sealing material 701 in the first space between first partition 214 and second partition 215, as shown in FIG. When the second sealing material 702 flowing within the first space reaches the end in the X direction where the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215 are provided, a portion of the second sealing material 702 flows from the first space into the second space through the through hole formed by the cutout section 216 of the first partition section 214 and the first sealing material 701, and flows within the second space. Another portion of the second sealing material 702 flows from the first space into the third space through the through hole formed by the cutout section 217 of the second partition section 215 and the first sealing material 701, and flows within the third space. Therefore, as shown in FIG. 9 , the second sealing material 702 is filled on top of the first sealing material 701 within each of the first, second, and third spaces. Therefore, for example, the second sealing material 702 can prevent corrosive gases, dust, moisture, etc. that have entered the second space or the third space through the gap between the slit 220 of the case 210 and the second terminal portion 603 of the fourth conductive plate 6D from passing through the first sealing material 701.

[0039] The first and second sealing steps described above are performed, for example, before the step of bending the second terminal portions 603 of the conductive plates 6A to 6D, which extend outside the semiconductor module 2 through the slits 220 of the case 210, along the top surface of the case 210. After the first and second sealing steps, as described above with reference to FIG. 7, nuts 10 are fitted into the nut fitting portions 230 provided on the top surface of the case 210, and the second terminal portions 603 of the conductive plates 6A to 6D are bent, thereby completing the semiconductor device 1 (semiconductor module 2) described in this embodiment. After the first and second sealing steps, the injection holes 213 of the case 210 used to inject the sealing material may be left as holes (open) or may be closed by performing a predetermined process. Furthermore, the manufacturing procedure for the semiconductor device 1 (semiconductor module 2) of this embodiment, including the step of injecting the sealing material, is not limited to the above-described procedure. For example, the step of injecting the sealing material is not limited to the two steps described above, and may include three or more steps.

[0040] Fig. 11 is a side cross-sectional view of a step of injecting a first sealing material in a manufacturing process of a semiconductor module in which the partition does not have a cutout section. Fig. 12 is a side cross-sectional view of a step of injecting a second sealing material in a manufacturing process of a semiconductor module in which the partition does not have a cutout section. The ranges shown in Fig. 11 and Fig. 12 each correspond to region R in Fig. 4.

[0041] When a semiconductor module is manufactured (assembled) using a case 210 that does not have the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215, the housing space of the case 210 is divided into a first space, a second space, and a third space after the first sealing step is completed, as illustrated in FIG. 11 . At this time, no through-holes communicating the first space with the second space or the first space with the third space are formed. Therefore, when the second sealing step is subsequently performed in which a second sealing material 702 (additional sealing material) is injected into the first space through the injection hole 213 of the case 210, the second sealing material 702 that flows along the upper surface of the first sealing material 701 in the first space cannot be supplied into the second space and the third space, as illustrated in FIG. 12 . Therefore, after the second sealing step is completed, the upper surface of the first sealing material 701 is exposed in the second space and the third space.

[0042] If the second sealing material 702 is not filled on top of the first sealing material 701, corrosive gases, dust, moisture, etc. that enter the second space or the third space through the gap between the slit 220 of the case 210 and the second terminal portion 603 of the fourth conductor plate 6D may pass through the first sealing material 701, causing corrosion of circuit components, etc. of the circuit board 4, a decrease in insulation, etc.

[0043] In contrast, in the manufacturing process of the semiconductor module 2 of this embodiment, at least at the start of the second sealing step, the first space is in communication with each of the second space and the third space, with insulation between the conductive plates ensured by the first partition 214, the second partition 215, and the first sealing material 710. Therefore, as described above with reference to FIGS. 9 and 10 , the second sealing material 702 injected into the first space flows into and spreads into the second space and the third space, and the second sealing material 702 can be filled on top of the first sealing material 701 in the second space and the third space. Therefore, the second sealing material 702 can prevent corrosive gases, dust, moisture, etc. that have entered the second space or the third space through the gap between the slit 220 of the case 210 and the second terminal portion 603 of the fourth conductive plate 6D from passing through the first sealing material 701.

[0044] The cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215, which are for connecting the first space with the second space and the third space at the start of the second sealing step, are provided at a position outside the portion of the first partition section 214 that extends along the base 601 of the first conductive plate 6A, and at a position outside the portion of the second partition section 215 that extends along the base 601 of the second conductive plate 6B, respectively. Therefore, in the semiconductor module 2 of this embodiment, the lower end portions of the portions of the first partition section 214 and the second partition section 215 of the case 210 that extend along the conductive plates are in contact with the first sealing material 701 and are buried therein. Therefore, after second sealing material 702 is injected, insulation between the conductive plates is ensured even if the first space and the second space communicate at cutout section 216 and the first space and the third space communicate at cutout section 217. Furthermore, first partition section 214 and second partition section 215 protruding from the inner surface of lid section 212 of case 210 have their X-direction ends connected to the inner surfaces of side section 211 of case 210, which increases the strength of case 210 and does not impair their function as ribs for preventing deformation of case 210 due to warping or twisting.

[0045] As a solution to the problems of the conventional example described above with reference to FIGS. 11 and 12, it is possible to provide multiple injection holes for the sealant, particularly in the second sealing step. However, in this case, the following problems arise, for example: The case shape becomes complicated because an injection hole corresponding to each space is required; When sealant is filled through multiple injection holes, the takt time becomes long; and When sealant is filled through multiple injection holes, the height becomes uneven. The present invention can avoid these problems.

[0046] It should be noted that the shapes of the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215 in the case of the semiconductor module 2 of this embodiment are not limited to the shapes exemplified in Figures 3 to 5. Below, with reference to Figures 13 to 16, some modified examples of the shapes of the cutout sections 216 and 217 and other modified examples will be described.

[0047] Fig. 13 is a perspective view illustrating a first modified example of a cutout section provided in the partition section. Fig. 14 is a side cross-sectional view illustrating a second modified example of a cutout section provided in the partition section. Fig. 15 is a perspective view illustrating a third modified example of a cutout section provided in the partition section. Fig. 16 is a perspective view illustrating a fourth modified example of a cutout section provided in the partition section.

[0048] 13, the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215 each continue to the inner surface of the side surface section 211. In this way, the through holes formed by the cutout sections 216 and 217 are larger, and when the second sealing material 702 is injected, the second sealing material 702 flows more easily from the first space into the second space and the third space, respectively, and the time required for the step of injecting the second sealing material 702 can be shortened.

[0049] 13, a beam portion 218 is provided that connects the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215. By providing such a beam portion 218, for example, it is possible to suppress the influence that the height of each of the partition sections 214, 215 from the lid section 212 is reduced at the cutout sections 216 and 217 on the strength of the case 210 and deformation such as warping and twisting.

[0050] In the case 210 illustrated in Fig. 14, the lower end surface of the cutout section 216 is curved so that the height of the end of the cutout section 216 in the X direction from the lid portion 212 changes continuously. The case 210 is formed, for example, by injection molding. When the case 210 is formed by injection molding, for example, by curvedly forming the lower end surface of the cutout section 216 as illustrated in Fig. 14, the fluidity of the insulating material in the cavity of the mold can be further improved compared to the case where the height changes stepwise (discontinuously) as illustrated in Fig. 13, etc., and shape defects of the cutout sections 216, 217, etc. can be further reduced.

[0051] 15, the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215 each continue to the inner surface of the side surface section 211. In addition, a first beam section 218 that connects the cutout sections and a second beam section 219 that connects the first beam section 218 and the side surface section 211 of the case 210 are provided between the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215. The end of the second beam section 219 that connects to the side surface section 211 is curved, thereby increasing the connection area between the second beam section 219 and the side surface section 211 in the Z direction. By providing such second beam portion 219, deformation such as warping or twisting of side surface portion 211 to which first partition portion 214 and second partition portion 215 are connected can be suppressed.

[0052] 16, the height from the lid portion 212 to the bottom end of the cutout section 216 of the first partition section 214 and the cutout section 217 of the second partition section 215 is 0. The cutout sections 216 and 217 may be located in any position that does not affect the insulating performance between the conductor plates 6A, 6B, and 6C provided by the partition sections 214 and 215 extending in the X direction, and may be, for example, sections that divide (separate) the conductor plates at a position that does not overlap with them.

[0053] The configurations of the cutout sections 216, 217 in the partitions 214, 215 of the case 210 described above with reference to FIGS. 1 to 16 are merely examples of the cutout sections 216, 217 in the semiconductor module 2 according to this embodiment. The cutout sections 216, 217 in the semiconductor module 2 according to this embodiment may have multiple features separately illustrated in multiple drawings. Furthermore, the positions, shapes, and the like of the cutout sections 216, 217 in the semiconductor module 2 according to this embodiment are not limited to those described above and can be modified as appropriate. For example, depending on the relative positions of the base 601 of the first conductive plate 6A, the base 601 of the second conductive plate 6B, and the base 601 of the third conductive plate 6C, the position where the cutout section 216 of the first partition 214 and the position where the cutout section 217 of the second partition 215 are provided may be on opposite ends in the X direction. Furthermore, each partition may have multiple cutout sections.

[0054] The outer shape of case 210 and the shape of the storage space are not limited to any particular shape. For example, the storage space of case 210 may be divided into four or more spaces by three or more partitions and the first sealing material. Alternatively, the storage space of case 210 may be divided into two spaces by one partition and the first sealing material.

[0055] Furthermore, the above-described semiconductor module 2 may itself be incorporated as a semiconductor device into an electronic device such as a power conversion device. The terms "semiconductor module" and "semiconductor device" are merely convenient expressions for distinguishing between what they respectively refer to and may be interchanged. For example, the semiconductor module 2 in this specification may be interchanged as semiconductor device 2, and the semiconductor device 1 in this specification may be interchanged as semiconductor module 1 or other terms.

[0056] The semiconductor device 1 including the semiconductor module 2 of the above-described embodiment is not limited to a specific application, but is particularly suitable for use in high-temperature, high-humidity environments. For example, the semiconductor module 2 of the above-described embodiment can be applied to a power conversion device such as an inverter device for an in-vehicle motor. A vehicle to which the semiconductor device 1 according to the present invention is applied will be described with reference to FIG. 17.

[0057] Fig. 17 is a schematic plan view showing an example of a vehicle to which the semiconductor device according to the present invention is applied. Vehicle 901 shown in Fig. 17 is, for example, a four-wheeled vehicle having four wheels 902. Vehicle 901 may be, for example, an electric vehicle in which the wheels are driven by a motor or the like, or a hybrid vehicle that uses power from an internal combustion engine in addition to a motor.

[0058] The vehicle 901 includes a drive unit 903 that applies power to the wheels 902, and a control device 904 that controls the drive unit 903. The drive unit 903 may be configured with at least one of an engine, a motor, and a hybrid of an engine and a motor, for example.

[0059] The control device 904 controls the drive unit 903 (for example, power control). The control device 904 includes a semiconductor device 1 including the semiconductor module 2 of the above-described embodiment. The semiconductor device 1 can be configured to control power to the drive unit 903. The semiconductor device 1 can be configured such that a heat dissipation member such as a heat sink that dissipates heat generated in the semiconductor module 2, and a cooler 3 that cools the semiconductor module 2 or the heat dissipation member are attached to the semiconductor module 2. The semiconductor device 1 may include multiple semiconductor modules 2. Furthermore, the semiconductor device 1 may refer to the semiconductor module 2 itself.

[0060] The semiconductor device 1 (semiconductor module 2) of the control device 904 installed in the vehicle 901 operates while the vehicle 901 is traveling, and may operate in an environment of high temperature (for example, around 100°C) and high humidity (for example, humidity of 90%). For this reason, by applying the semiconductor device 1 including the semiconductor module 2 according to the above-described embodiment, it is possible to suppress corrosion of the circuit components of the circuit board 4 and deterioration of insulation due to corrosive gases, moisture, dust, etc. that have entered the housing space of the case 210, and it is possible to reduce the frequency of inspection of the control device 904, the frequency of replacement of the semiconductor module 2, etc.

[0061] The embodiments of the semiconductor module 2 according to the present invention are not limited to the above-described embodiments, and may be variously changed, substituted, or modified without departing from the spirit of the technical idea. Furthermore, if the technical idea can be realized in a different way due to technological advances or other derived technologies, it may be implemented using that method. Therefore, the scope of the claims covers all embodiments that may fall within the scope of the technical idea.

[0062] The features of the above-described embodiment will be summarized below.

[0063] The semiconductor module according to the above-described embodiment includes a base on which a circuit board is mounted, and a case covering the circuit board mounted on the base, the case having a side portion surrounding the outer periphery of the circuit board and a lid portion located above the circuit board, a plurality of conductor plates each electrically connected to a conductor pattern of the circuit board and extending to the outside of the case through slits provided in the case, and a sealing material that seals the circuit board, wherein the case is arranged in an area surrounded by the lid portion, the side portion, and the circuit board, and has partition portions arranged between the plurality of conductor plates to provide insulation between the plurality of conductor plates, and the partition portions have cutout sections at positions that do not overlap with the plurality of conductor plates when viewed from a direction perpendicular to a plane in which the plurality of conductor plates and the partition portions each extend parallel, so that the height of a second portion where the plurality of conductor plates do not overlap is lower than the height of a first portion that overlaps with the plurality of conductor plates.

[0064] In the semiconductor module according to the above-described embodiment, the tip portion in the height direction of the portion of the partition that overlaps with the two conductive plates is in contact with the sealing material.

[0065] In the semiconductor module according to the above-described embodiment, the sealing material includes a first sealing material that seals the circuit board and a second sealing material on the first sealing material, and the upper surface of the first sealing material is located between the height-wise end position of the part of the partition portion that overlaps with the two conductor plates and the height-wise end position of the cutout section.

[0066] In the semiconductor module according to the above-described embodiment, the partition portion of the case has a first partition portion and a second partition portion extending parallel to each other, and further has a beam portion connected to the cutout section of the first partition portion and the cutout section of the second partition portion.

[0067] In the semiconductor module according to the above-described embodiment, the partition portion of the case has a first partition portion and a second partition portion extending parallel to each other, and further has a first beam portion connected to the cutout section of the first partition portion and the cutout section of the second partition portion, and a second beam portion connected to the first beam portion and the side portion.

[0068] In the semiconductor module according to the above-described embodiment, the height of the cutout section of the partition from the lid portion varies along a curved surface.

[0069] The semiconductor device according to the above-described embodiment includes the semiconductor module described above, and a cooler disposed on the surface of the base of the semiconductor module opposite to the surface on which the circuit board is mounted.

[0070] The vehicle according to the above-described embodiment includes the semiconductor module or semiconductor device. [Industrial Applicability]

[0071] As described above, the present invention has the effect of suppressing corrosion of circuit components on a circuit board that is housed in a case with an integrated lid and sealed with a sealant injected through an injection hole provided in the lid, and is particularly useful for industrial or electrical semiconductor modules, semiconductor devices, and vehicles.

[0072] This application is based on Japanese Patent Application No. 2022-148608, filed September 16, 2022, the contents of which are incorporated herein in their entirety.

Claims

1. a base on which a circuit board is mounted; a case for covering the circuit board mounted on the base, the case having a side surface surrounding the outer periphery of the circuit board and a lid located above the circuit board; a plurality of conductor plates each electrically connected to the conductor pattern of the circuit board and extending to the outside of the case through a slit provided in the case; an encapsulant for encapsulating the circuit board; Including, the case has partitions that are arranged in an area surrounded by the lid portion, the side surface portion, and the circuit board, and are arranged between the plurality of conductive plates to provide insulation between the plurality of conductive plates; The partition portion has a notched section at a position where it does not overlap with the plurality of conductive plates when viewed from a direction perpendicular to a plane in which the plurality of conductive plates and the partition portion extend in parallel, so that a height of a second portion where the plurality of conductive plates do not overlap is lower than a height of a first portion where the plurality of conductive plates overlap. A semiconductor module characterized by:

2. The tip end portion in the height direction of the part of the partition portion that overlaps with the plurality of conductive plates is in contact with the sealing material.

2. The semiconductor module according to claim 1.

3. the encapsulant includes a first encapsulant that encapsulates the circuit board and a second encapsulant on the first encapsulant; The upper surface of the first sealing material is located between the tip position in the height direction of the portion of the partition that overlaps with the plurality of conductive plates and the tip position in the height direction of the notched section.

2. The semiconductor module according to claim 1.

4. The partition portion of the case has a first partition portion and a second partition portion extending parallel to each other, and further has a beam portion connected to the notched section of the first partition portion and the notched section of the second partition portion.

2. The semiconductor module according to claim 1.

5. The partition portion of the case has a first partition portion and a second partition portion extending parallel to each other, and further has a first beam portion connected to the notched section of the first partition portion and the notched section of the second partition portion, and a second beam portion connected to the first beam portion and the side surface portion.

2. The semiconductor module according to claim 1.

6. The height of the partition from the lid portion in the cutout section varies along a curved surface.

2. The semiconductor module according to claim 1.

7. a semiconductor module according to any one of claims 1 to 6; a cooler disposed on a surface of the base of the semiconductor module opposite to a surface on which the circuit board is mounted; A semiconductor device comprising:

8. A vehicle comprising the semiconductor module according to any one of claims 1 to 6.

9. A vehicle characterized by comprising the semiconductor device described in claim 7.

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