Semiconductor device

Abstract

To provide a semiconductor device in which a lid is securely fitted into a case and the height is reduced.SOLUTION: A semiconductor device 1 includes a case 10 that accommodates a circuit board 70 on which a semiconductor element 71 is mounted in board accommodation areas A1 to A3, and a lid 20 that covers the board accommodation areas A1 to A3. The lid 20 includes a plurality of extensions 21 to 24 including a first extension 21 that extends toward the board accommodation areas A1 to A3 (negative side in a Z direction) and has a protruding portion 21a that protrudes in a first direction (positive side in an X direction), and a second extension 22 that extends toward the board accommodation areas A1 to A3 (negative side in the Z direction) and has a protruding portion 22a that protrudes in a second direction (negative side in the X direction) opposite to the first direction, and a plurality of deformation holes 25a to 25f. The case 10 includes a plurality of hooks 11a, 11b, 12a, 13a on which the protruding portions 21a to 24a of the extensions 21 to 24 are hooked, respectively.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a semiconductor device having a lid fitted into a case. [Background technology]

[0002] 2. Description of the Related Art Conventionally, semiconductor devices have a circuit board on which semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors) are mounted, and are used in inverter devices and the like (see, for example, Patent Documents 1 to 10). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Utility Model Registration No. 3237816 [Patent Document 2] International Publication No. 2017 / 163638 [Patent Document 3] JP 2023-88146 A [Patent Document 4] Patent Publication No. 2022-65692 [Patent Document 5] International Publication No. 2019 / 058454 [Patent Document 6] Patent Publication No. 2021-72329 [Patent Document 7] JP 2021-129451 A [Patent Document 8] JP 2018-139278 A [Patent Document 9] JP 2021-114511 A [Patent Document 10] JP 2014-150204 A Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, when placing a lid on a semiconductor device, although fitting can be said to be a simple and easy configuration, it is required that the lid be securely fitted into the case from the viewpoint of protecting the circuit board, etc. Therefore, it is conceivable to provide a protrusion for fitting on an extension extending downward from the lid, but in this case, the extension extends downward a long distance in order to reduce the reaction force caused by deformation when the protrusion is hooked onto the case, and the height of the semiconductor device increases.

[0005] An object of the present invention is to provide a semiconductor device in which the lid can be securely fitted into the case and which can be made low-profile. [Means for solving the problem]

[0006] In one aspect, a semiconductor device comprises a case that accommodates a circuit board on which a semiconductor element is mounted in a board accommodating area, and a lid that covers the board accommodating area, the lid having a plurality of extension portions including a first extension portion having a convex portion extending toward the board accommodating area and protruding in a first direction, and a second extension portion having a convex portion extending toward the board accommodating area and protruding in a second direction opposite to the first direction, and a plurality of deformation holes, and the case has a plurality of hook portions onto which the convex portions of the extension portions can be hooked. Effect of the Invention

[0007] According to this aspect, the lid can be securely fitted into the case, and the height can be reduced. [Brief description of the drawings]

[0008] [Figure 1] 1 is a plan view showing a semiconductor device according to an embodiment; [Diagram 2] 1 is a perspective view showing a semiconductor device according to an embodiment; [Diagram 3] FIG. 1 is a plan view illustrating a semiconductor device with a lid removed according to one embodiment. [Figure 4] FIG. 1 is a perspective view of a semiconductor device with a lid removed, according to one embodiment. [Diagram 5] FIG. 2 is a cross-sectional view of FIG. 1 . [Figure 6] FIG. 2 is an enlarged view of a portion VI in FIG. [Figure 7] FIG. 7 is a cross-sectional view taken along line VII-VII of FIG. [Figure 8] FIG. 2 is an enlarged view of part VIII in FIG. [Figure 9] 9 is a cross-sectional view taken along line IX-IX of FIG. 8. [Figure 10] 13 is a plan view showing second deformation holes and the like in a first modified example of one embodiment (corresponding to FIG. 6 which is an enlarged view of a portion VI in FIG. 1). FIG. [Figure 11] 9 is a cross-sectional view showing a fourth deformation hole and the like in a second modified example of the embodiment (corresponding to FIG. 9, a cross-sectional view taken along line IX-IX in FIG. 8). FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, a semiconductor device according to an embodiment of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiment described below, and can be appropriately modified and implemented without departing from the gist of the present invention.

[0010] 1 and 2 are a plan view and a perspective view showing a semiconductor device 1 according to an embodiment.

[0011] 3 and 4 are a plan view and a perspective view showing the semiconductor device 1 with the lid 20 removed.

[0012] Fig. 5 is a cross-sectional view taken along line VV in Fig. 1. Fig. 6 is an enlarged view of a portion VI in Fig. 1. Fig. 7 is a cross-sectional view taken along line VII-VII in Fig. 6. Fig. 8 is an enlarged view of a portion VIII in Fig. 1. Fig. 9 is a cross-sectional view taken along line IX-IX in Fig. 8.

[0013] 1 to 9 and 10 and 11 described later, the vertical direction of the semiconductor device 1 (thickness direction of the circuit board 70) is defined as the Z direction, and of the X and Y directions perpendicular to the Z direction, the longitudinal direction of the semiconductor device 1 (lid 20) is defined as the X direction, and the lateral direction of the semiconductor device 1 (lid 20) is defined as the Y direction. In some cases, the X direction may be called the left-right direction, the Y direction may be called the front-back direction, and the Z direction may be called the up-down direction. These directions are terms used for convenience of explanation, and the corresponding relationships between the X, Y, and Z directions change depending on the mounting posture of the semiconductor device 1.

[0014] The semiconductor device 1 according to the present embodiment is applied to a power conversion device such as a power control unit, and is a power semiconductor module constituting an inverter circuit. The semiconductor device 1 can be used for any purpose, but is used, for example, as an inverter device for an in-vehicle or industrial motor.

[0015] 3 and 5, the semiconductor device 1 includes a case 10 that houses three circuit boards 70 (shown by hidden dashed lines in FIG. 3 because they are located inside the gel G) on which semiconductor elements 71 are mounted in board housing areas A1, A2, and A3, and a lid 20 that covers the board housing areas A1, A2, and A3. Note that in FIG. 5, the case 10, the lid 20, and the gel G are hatched to show cross sections.

[0016] 3 and 4, the case 10 has a rectangular shape in a plan view, with a cylindrical storage wall 11 protruding upward from the top surface. Three board storage areas A1 to A3 are located inside the storage wall 11, each of which stores a circuit board 70. These board storage areas A1 to A3 have the same or approximately the same size in a plan view.

[0017] A first hook 11a protruding toward the substrate housing area A1 (negative side in the X direction) is provided from the right end of the housing wall 11. A second hook 11b protruding toward the substrate housing area A3 (positive side in the X direction) is provided from the left end of the housing wall 11. The first hook 11a and the second hook 11b are provided on the upper part of the inner circumferential surface of the housing wall 11. The first hook 11a and the second hook 11b hook the convex parts 21a and 22a of the first extension part 21 and the second extension part 22 of the lid 20 shown in Figs. 1 and 2 described later. In Figs. 3 and 4, the first hook 11a and the second hook 11b are provided at the center of the housing wall 11 in the short side direction of the case 10, but the positions in the short side direction are not particularly limited.

[0018] 3 and 4, lid receivers 11c and 11d on which the lid 20 is placed are provided at the front right corner and the front left corner of the storage wall 11. Also, as shown in Fig. 3, a lid receiver 11e having the same height as the first partition wall 12 and the second partition wall 13 is provided at the rear of the storage wall 11, spanning from the rear right corner to the rear left corner.

[0019] The case 10 has a first partition wall 12 and a second partition wall 13 that separate the three substrate accommodating regions A1 to A3 aligned in the X direction. A metal base 80 (described later) is disposed at the bottom of each of the substrate accommodating regions A1 to A3, and the case 10 is hollow, penetrating each of the substrate accommodating regions A1 to A3 in the vertical direction.

[0020] The upper surface of the first partition wall 12 is provided with a third hook portion 12a protruding toward the substrate accommodation area A1 side (X-direction positive side). The upper surface of the second partition wall 13 is provided with a fourth hook portion 13a protruding toward the substrate accommodation area A3 side (X-direction negative side). The upper surface of the third hook portion 12a is located higher than the upper surface of the other parts of the first partition wall 12. The upper surface of the fourth hook portion 13a is located higher than the upper surface of the other parts of the second partition wall 13. The third hook portion 12a and the fourth hook portion 13a hook the protrusions 23a and 24a of the third extension portion 23 and the fourth extension portion 24 of the lid 20. The third hook portion 12a and the fourth hook portion 13a are examples of intermediate hook portions. The case 10 is fitted into the lid 20 by a snap-fit ​​structure formed by the hooks 11a, 11b, 12a, 13a and the protrusions 21a to 24a. The hooks 11a, 11b, 12a, 13a are integrally formed with the case 10 by, for example, injection molding. The protrusions 21a to 24a and the extensions 21 to 24 themselves can also be called claws. The hooks 11a, 11b, 12a, 13a may also be recesses (concave portions) provided on the wall surface of the case 10 (the storage wall 11, the first partition wall 12, or the second partition wall 13). The areas below the hooks 11a, 11b, 12a, 13a can also be considered as concave portions.

[0021] A plurality of (e.g., six as shown in FIG. 3) fixing holes 14 are formed along the outer periphery of the case 10. The fixing holes 14 are holes for inserting bolts for fixing the semiconductor device 1 to an external device such as a cooler (not shown), for example.

[0022] The case 10 has a positioning hole 15 provided on the positive side of the Y direction from the housing wall 11 and a positioning hole 16 provided on the negative side of the Y direction from the housing wall 11. These positioning holes 15, 16 are located at different positions in the X direction. While the positioning hole 15 has a circular shape in a plan view, the positioning hole 16 is an elongated hole extending obliquely toward the positioning hole 15 in a plan view. This allows the two positioning pins to be inserted into the positioning holes 15, 16 even if the distance between a positioning pin of an external device inserted into the positioning hole 15 and a positioning pin of an external device inserted into the positioning hole 16 varies due to tolerances or the like.

[0023] The resin for the case 10 may be selected from insulating resins such as polyphenylene sulfide (PPS), polybutylene terephthalate (PBT), polybutyl acrylate (PBA), polyamide (PA), acrylonitrile butadiene styrene (ABS), liquid crystal polymer (LCP), polyether ether ketone (PEEK), polybutylene succinate (PBS), urethane, silicone, etc. The selected resin may be a mixture of two or more resins. The resin may contain a filler (e.g., glass filler) to improve strength or functionality.

[0024] As shown in Figs. 4 and 5, the gel G injected into the substrate housing areas A1 to A3 seals the circuit substrate 70, the semiconductor element 71 mounted on the circuit substrate 70, and the like. The gel G is, for example, a transparent silicone gel. Instead of the gel G, a sealing resin may be used. The sealing resin is, for example, made of a thermosetting resin. The sealing resin preferably contains any one of epoxy, silicone, urethane, polyimide, polyamide, and polyamideimide. For example, an epoxy resin mixed with a filler is suitable as the sealing resin in terms of insulation, heat resistance, and heat dissipation.

[0025] As shown in Fig. 1 and Fig. 6 to Fig. 9, the lid 20 has a first extending portion 21, a second extending portion 22, a third extending portion 23, and a fourth extending portion 24, each of which extends in the negative Z direction. These extending portions 21 to 24 are formed integrally with the lid 20 by, for example, injection molding. The first extending portion 21 and the fourth extending portion 24 have protrusions 21a, 24a protruding in the positive X direction, which is an example of a first direction. The second extending portion 22 and the third extending portion 23 have protrusions 22a, 23a protruding in the negative X direction, which is an example of a second direction opposite to the first direction.

[0026] The first extension portion 21 is located at one end (right end) in the longitudinal direction (X direction) of the lid 20, and the second extension portion 22 is located at the other end (left end) in the longitudinal direction of the lid 20. That is, the first extension portion 21 and the second extension portion 22 are located at both ends in the longitudinal direction of the lid 20, and the convex portions 21a, 22a protrude away from each other in the longitudinal direction of the lid 20. When the lid 20 forms a square in a plan view, both the left-right direction (X direction) and the front-back direction (Y direction) can be called the longitudinal direction of the lid 20.

[0027] 6 and 7, the second extension portion 22 extends (length L, which is the height) to the negative side in the Z direction from a position adjacent to the recess 26b provided at the end (left end) in the longitudinal direction (X direction) of the lid 20. That is, the second extension portion 22 is provided at a position recessed to the right (positive side in the X direction) from the left end of the lid 20 in the longitudinal direction (X direction).

[0028] The first extending portion 21 is symmetrical to the second extending portion 22, and like the second extending portion 22, extends to the negative side in the Z direction from a position adjacent to a recess 26a provided at an end (right end) in the longitudinal direction (X direction) of the lid 20 as shown in Figures 1 and 2. That is, the first extending portion 21 is provided at a position recessed to the left (negative side in the X direction) from the right end of the lid 20 in the longitudinal direction (X direction).

[0029] 1 and 2, the third extension portion 23 is located closer to the first extension portion 21 (positive side in the X direction) than the center in the longitudinal direction of the lid 20 so that the protrusion 23a can be hooked onto the third hook portion 12a of the first partition wall 12. The fourth extension portion 24 is located closer to the second extension portion 22 (negative side in the X direction) than the center in the longitudinal direction of the lid 20 so that the protrusion 24a can be hooked onto the fourth hook portion 13a of the second partition wall 13. The third extension portion 23 and the fourth extension portion 24 are examples of one or more intermediate extension portions whose positions in the longitudinal direction (X direction) of the lid 20 are located between the first extension portion 21 and the second extension portion 22. As this intermediate extending portion, only one of the third extending portion 23 and the fourth extending portion 24 may be provided, or an extending portion having a convex portion that protrudes in a direction different from the convex portions 23a, 24a of the third extending portion 23 and the fourth extending portion 24 may be provided. In these cases, the intermediate hook portions, such as the third hook portion 12a and the fourth hook portion 13a, and the intermediate deformation holes described later may be provided in a number and orientation corresponding to the intermediate extending portions.

[0030] 8 and 9, the fourth extension portion 24 extends (length (height) L) from between the fourth deformation holes 25e, 25f provided in the lid 20 to the negative side in the Z direction. The third extension portion 23 is symmetrical to the fourth extension portion 24, and extends from between the third deformation holes 25c, 25d provided in the lid 20 to the negative side in the Z direction.

[0031] 1 and 2, the cover 20 has a first deformation hole 25a, a second deformation hole 25b, a third deformation hole 25c, 25d, and a fourth deformation hole 25e, 25f as an example of a plurality of deformation holes that relieve (release) reaction forces caused by the deformation of the first extension portion 21, the second extension portion 22, the third extension portion 23, and the fourth extension portion 24. The first deformation hole 25a relieves the reaction force caused by the deformation of the first extension portion 21, the second deformation hole 25b relieves the reaction force caused by the deformation of the second extension portion 22, the third deformation holes 25c, 25d relieve the reaction force caused by the deformation of the third extension portion 23, and the fourth deformation holes 25e, 25f relieve the reaction force caused by the deformation of the fourth extension portion 24. The center position in the Y direction of each of the deformation holes 25a-25f coincides with that of the extension parts 21-24 that are targets for reducing the reaction force due to deformation. Each of the deformation holes 25a-25f extends linearly in a direction (Y direction) perpendicular to the longitudinal direction (X direction) of the lid 20 and the depth direction (Z direction) of the board accommodation areas A1-A3, longer than the extension parts 21-24 that are targets for reducing the reaction force due to deformation. That is, each of the deformation holes 25a-25f extends forward and backward in the Y direction longer than the extension parts 21-24 that are targets for reducing the reaction force due to deformation. However, at least one of the deformation holes 25a-25f may extend in a direction different from the Y direction or in a curved shape, or may be formed in another shape such as a circle or an ellipse. Each of the deformation holes 25a-25f penetrates the lid 20 in the thickness direction (Z direction). The third deformation holes 25c and 25d are an example of intermediate deformation holes that reduce the reaction force caused by the deformation of the third extending portion 23 on both sides of the third extending portion 23 (intermediate extending portion) in the longitudinal direction (X direction) of the lid 20. Similarly, the fourth deformation holes 25e and 25f are an example of intermediate deformation holes that reduce the reaction force caused by the deformation of the fourth extending portion 24 on both sides of the fourth extending portion 24 (intermediate extending portion) in the longitudinal direction (X direction) of the lid 20. Here, if the deformation holes 25a to 25f are positioned around the extending portions 21 to 24, it can be said that the reaction force caused by the deformation of the extending portions 21 to 24 can be reduced (dissipated) by, for example, narrowing the width of the extending portions 21 to 24 in any direction to promote the deformation of the extending portions 21 to 24, or by absorbing the deformation of the extending portions 21 to 24 by the deformation holes 25a to 25f.

[0032] The first deformation hole 25a and the second deformation hole 25b are provided adjacent to the first extension portion 21 and the second extension portion 22 (see the second extension portion 22 and the second deformation hole 25b in FIG. 7). The first deformation hole 25a is symmetrical to the second deformation hole 25b.

[0033] As shown in FIG. 8, the fourth deformation hole 25e, which is located on the X-direction positive side of the fourth extension portion 24 among the fourth deformation holes 25e and 25f, has a recess 25e-1 recessed in the opposite direction to the X-direction positive side from which the protrusion 24a of the fourth extension portion 24 protrudes. This recess 25e-1 is located in the same region as the protrusion 24a in a plan view because it is located so as to sandwich the fourth extension portion 24 between the fourth deformation hole 25f and the fourth extension portion 24. In addition, the fourth deformation hole 25e has a recess 25e-2 recessed in the X-direction positive side opposite to the recess 25e-1. It can be said that these recesses 25e-1 and 25e-2 are provided to avoid interference with the fourth hook portion 13a of the second partition wall 13. It can also be said that one recess 25e-1 is provided to shorten the width of the fourth extension portion 24 in the X direction.

[0034] The third deformation holes 25c, 25d are symmetrical to the fourth deformation holes 25e, 25f, and the third deformation hole 25c, which is located on the negative side of the X direction from the third extension portion 23, has a recess (symmetrical to the recess 25e-1) recessed in the opposite direction to the negative side of the X direction from which the protrusion 23a of the third extension portion 23 protrudes, in a plan view. This recess is located in the same region as the protrusion 23a because it is located so as to sandwich the third extension portion 23 between the third deformation hole 25d and the third deformation hole 25c. In addition, the third deformation hole 25c has a recess (symmetrical to the recess 25e-2) recessed in the negative side of the X direction opposite to the recess. It can be said that these recesses are provided to avoid interference with the third hook portion 12a of the first partition wall 12. Moreover, one of the recesses (symmetrical to the recess 25e-1) can be said to be provided in order to shorten the width of the third extending portion 23 in the X direction.

[0035] 1 and 2, letters such as "U", "V", "W", "P1", "N1", "P2", "N2", "P3", "N3", "K1", and "E6" are formed on the top surface of the lid 20 so as to protrude upward from respective downwardly recessed rectangular areas. The top surface of each letter is aligned with the top surface of the lid 20 or is located below the top surface of the lid 20.

[0036] 1 to 4, case 10 is provided with main terminals (P terminal 30, N terminal 40, and M terminal 50) which function as external connection terminals for connection to an external conductor, and a control terminal 60. Each of P terminal 30, N terminal 40, and M terminal 50 is arranged on one circuit board 70. P terminal 30 may be called a positive terminal (input terminal) or a first main terminal, N terminal 40 may be called a negative terminal (output terminal) or a second main terminal, and M terminal 50 may be called an intermediate terminal (output terminal) or a third main terminal.

[0037] The P terminal 30 and the N terminal 40 are located on the negative side in the Y direction with respect to the circuit board 70. Moreover, the M terminal 50 is located on the positive side in the Y direction with respect to the circuit board 70. The P terminal 30, the N terminal 40, and the M terminal 50 may be formed by bending a metal material such as a copper material, a copper alloy material, an aluminum alloy material, or an iron alloy material by pressing or the like.

[0038] The P terminal 30, the N terminal 40, and the M terminal 50 are fastened to the external conductor at one end by a screw, and are joined at the other end to the circuit board 70 (for example, the circuit board 70c of the circuit board 70 or a copper block (not shown) provided on the circuit board 70c) while being bent, for example, multiple times as shown in FIG. 5, to be electrically connected.

[0039] The three circuit boards 70, each having a semiconductor element 71 mounted thereon, correspond to, for example, a U phase, a V phase, and a W phase, and together form a three-phase inverter circuit. Each of the three circuit boards 70 having the semiconductor elements 71 mounted thereon may be called a power cell or a semiconductor unit.

[0040] The circuit board 70 is, for example, a DCB (Direct Copper Bonding) board, an AMB (Active Metal Brazing) board, or a metal-based board. As shown in Fig. 5, the circuit board 70 has, for example, an insulating plate 70a, a heat sink 70b arranged on the lower surface of the insulating plate 70a, and a plurality of circuit boards 70c arranged on the upper surface of the insulating plate 70a. The circuit board 70 can be called a laminated board, and is formed, for example, in a rectangular shape when viewed from above.

[0041] The insulating plate 70a is made of, for example, aluminum oxide (Al 2 O 3 ), aluminum nitride (AlN), silicon nitride (Si 3 N 4 ), aluminum oxide and zirconium oxide (ZrO 2 The insulating plate 70a is made of an insulating material such as a ceramic material, a composite material with a ceramic material, a resin material such as epoxy, or an epoxy resin material using a ceramic material as a filler. The insulating plate 70a may be called an insulating layer or an insulating film.

[0042] The heat sink 70b has a predetermined thickness in the Z direction and is formed on the lower surface of the insulating plate 70a. The heat sink 70b is formed of a metal plate having good thermal conductivity, such as copper or aluminum. The heat sink 70b is joined to the upper surface of the metal base 80 by a joining material J1 such as solder.

[0043] The number of circuit boards 70c formed on the upper surface of the insulating plate 70a may be any number equal to or greater than one. The circuit boards 70c are metal layers such as copper foil, and are formed, for example, in the form of islands on the insulating plate 70a while being electrically insulated from one another. The circuit boards 70c may also be called circuit layers.

[0044] A semiconductor element 71 is mounted on a mounting surface, which is the upper surface of the circuit board 70 (circuit board 70c), via a bonding material J2. Although two semiconductor elements 71 are shown per circuit board 70 in Fig. 3, the number of semiconductor elements 71 is arbitrary. The semiconductor element 71 is formed in a square or rectangular shape in a plan view using a semiconductor substrate such as silicon (Si), silicon carbide (SiC), gallium nitride (GaN), diamond, or the like.

[0045] As the semiconductor element 71, a switching element such as an IGBT or a power MOSFET (Metal Oxide Semiconductor Field Effect Transistor), or a diode such as an FWD (Free Wheeling Diode) may be used. The switching element and the diode may be connected in inverse parallel. As the semiconductor element 71, an RC (Reverse Conducting)-IGBT element in which an IGBT and an FWD are integrated, or a power MOSFET element, or an RB (Reverse Blocking)-IGBT having a sufficient withstand voltage against reverse bias may be used. In particular, the RC-IGBT element can reduce the size of the internal circuit by passing electricity in both directions, and thus the size of the semiconductor device 1 (circuit board 70).

[0046] The semiconductor element 71 is conductively connected to a predetermined circuit board 70c via a metal wiring board (not shown). The metal wiring board is formed by bending a metal material such as copper, copper alloy, aluminum alloy, or iron alloy by pressing or the like. For example, the semiconductor element 71 and the metal wiring board are joined by a joining material such as solder. The metal wiring board may be called a lead frame. Note that other connecting members such as conductor wires may be arranged instead of the metal wiring board. The semiconductor element 71 is directly or indirectly connected to the control terminal 60 by using a connecting member. For example, ten of these control terminals 60 are arranged for each circuit board 70 in the housing wall 11 of the case 10. More specifically, five of the ten control terminals 60 are arranged for each circuit board 70 so as to sandwich the M terminal 50 in the left-right direction (X direction).

[0047] In the above explanation, an example was given in which three main terminals (P terminal 30, N terminal 40, and M terminal 50) are provided on each of the three circuit boards 70, but the semiconductor device 1 only needs to include at least one circuit board 70, and the number of main terminals and control terminals can be any number.

[0048] The metal base 80 is a rectangular plate-like member. The metal base 80 functions as a heat-conducting member that conducts heat generated by the semiconductor element 71 to a cooler (not shown) located below the metal base 80, and is formed of a metal plate such as a copper plate or an aluminum plate. The metal base 80 and the cooler are joined together via a heat-conducting material such as thermal grease or thermal compound.

[0049] Next, fitting of the lid 20 into the case 10 will be described.

[0050] First, the semiconductor element 71 is mounted on the circuit board 70, and the P terminal 30, the N terminal 40, the M terminal 50, and the control terminal 60 are electrically connected to the circuit board 70 and the semiconductor element 71, and then gel G is injected into the board accommodating areas A1 to A3.

[0051] Then, the lid 20 is placed horizontally in the housing wall 11 so as to cover the substrate housing areas A1 to A3. The bottom surface of the lid 20 contacts the upper surfaces of the lid receivers 11c, 11d, and 11e, the first partition wall 12, and the second partition wall 13 shown in Figs. 3 and 4, and in the process of placing the lid 20, each of the extensions 21 to 24 is elastically deformed. Specifically, the first extension 21 is deformed in the negative X-direction when the protrusion 21a is hooked on the first hook 11a. The second extension 22 is deformed in the positive X-direction when the protrusion 22a is hooked on the second hook 11b. The third extension 23 is deformed in the positive X-direction when the protrusion 23a is hooked on the third hook 12a. The fourth extension 24 is deformed in the negative X-direction when the protrusion 24a is hooked on the fourth hook 13a. Furthermore, if protrusions (not shown) extending upward are provided on the convex portions 21a to 24a and these protrusions engage with recesses (not shown) or protrusions (not shown) provided on the bottom surfaces of the hook portions 11a, 11b, 12a, and 13a, the lid 20 can be more securely fitted into the case 10.

[0052] As described above, the reaction force due to the deformation of the extensions 21-24 is mitigated by the deformation holes 25a-25f. When the bottom surface of the lid 20 is in contact with the upper surfaces of the lid receivers 11c, 11d, and 11e, the first partition wall 12, and the second partition wall 13, the protrusions 21a-24a of the extensions 21-24 are hooked onto the hook portions 11a, 11b, 12a, and 13a, respectively, and the extensions 21-24 are elastically deformed to return to their original shapes.

[0053] FIG. 10 is a plan view showing second deformation holes 25b-1 and the like in a first modified example of the present embodiment (corresponding to FIG. 6 which is an enlarged view of a portion VI in FIG. 1).

[0054] The second deformation hole 25b shown in FIG. 6 is a long hole extending in a straight line in the Y direction, but the second deformation hole 25b-1 in the first modified example shown in FIG. 10 extends in the Y direction, but is located farther away from the protrusion 22a of the second extension 22 in the longitudinal direction (positive side of the X direction) of the lid 20 at the center portion 25b-1c than both end portions (end portions 25b-1a, 25b-1b). In the second deformation hole 25b-1, the center portion 25b-1c extending in a straight line in the Y direction and both end portions (end portions 25b-1a, 25b-1b) extending in a straight line in the Y direction at positions on the negative side of the X direction from the center portion 25b-1c are integrally provided via obliquely extending portions. That is, the second deformation hole 25b-1 is shaped to follow the outer periphery of the lid 20.

[0055] In this way, the central portion 25b-1c is located at a position on the X-direction positive side relative to both end portions (ends 25b-1a, 25b-1b) and the second deformation hole 25b-1 is shaped to follow the outer peripheral edge of the lid 20, so that the longitudinal length from the other end (left end) of the lid 20 to the end 25b-1a, the longitudinal length from the recess 26b-1 to the central portion 25b-1c, and the longitudinal length from the other end (left end) of the lid 20 to the end 25b-1b can be made constant. Therefore, the deformation of the second extension portion 22 is promoted, and the reaction force caused by the deformation of the second extension portion 22 can be more reliably alleviated. In this first modified example, the recess 26b-1 is different from the recess 26b shown in FIG. 6 in that it is not rectangular in plan view, and the width in the Y direction is continuously narrowed from the opening portion (left end) toward the X-direction positive side (right side).

[0056] Here, the first deformation hole 25a can be symmetrical to the second deformation hole 25b-1. The third deformation hole 25d can be the same shape as the second deformation hole 25b-1, and the fourth deformation hole 25f can be symmetrical to the second deformation hole 25b-1. The recess 26a can be symmetrical to the recess 26b-1.

[0057] FIG. 11 is a cross-sectional view showing a fourth deformation hole 25f-1 and the like in a second modified example of the present embodiment (corresponding to FIG. 9, which is a cross-sectional view taken along line IX-IX in FIG. 8).

[0058] Although each of the deformation holes 25a-25f penetrates the lid 20 in the thickness direction (Z direction) in the above example, it may be a depression provided in the bottom surface (surface on the side of the substrate accommodating areas A1-A3) of the lid 20 in the direction from the bottom surface to the top surface (positive side of the Y direction) of the lid 20, like the fourth deformation hole 25f-1 shown in Fig. 11. In particular, when the lid 20 is thick, the depth of the deformation holes such as the fourth deformation hole 25f-1 that do not penetrate the lid 20 can be made deeper to more easily alleviate the reaction force caused by the deformation of the extensions 21-24.

[0059] In the present embodiment described above, the semiconductor device 1 includes a case 10 that accommodates a circuit board 70 on which a semiconductor element 71 is mounted in the board accommodation areas A1-A3, and a lid 20 that covers the board accommodation areas A1-A3. The lid 20 has a plurality of extensions 21-24 on the board accommodation areas A1-A3 side (negative side in the Z direction) with extending protrusions 21a-24a, and a plurality of deformation holes 25a-25f that, for example, relieve reaction forces due to deformation of the plurality of extensions 21-24. The case 10 has a plurality of hooks 11a, 11b, 12a, 13a on which the protrusions 21a-24a of the extensions 21-24 are hooked, respectively. The multiple extension portions 21-24 include a first extension portion 21 having a convex portion 21a protruding in a first direction (positive side of the X-direction) and a second extension portion 22 having a convex portion 22a protruding in a second direction (negative side of the X-direction) opposite to the first direction (positive side of the X-direction).

[0060] As a result, the convex parts 21a, 22a of the first extension part 21 and the second extension part 22 protruding in opposite directions can be hooked on the first hook part 11a and the second hook part 11b of the case 10. Therefore, the lid 20 can be reliably fitted into the case 10. The deformation holes 25a-25f relieve the reaction force caused by the deformation of the extension parts 21-24, so that the extension parts 21-24 do not need to secure the length L for mitigating the warping force, and the length L of the extension parts 21-24 extending toward the substrate housing areas A1-A3 (Z direction negative side) can be shortened. This allows the height of the extension parts 21-24, and therefore the height of the semiconductor device 1, to be reduced. Therefore, according to this embodiment, the lid 20 can be reliably fitted into the case 10 and the semiconductor device 1 can be made low-profile. Furthermore, by reducing the reaction force caused by the deformation of the extensions 21-24, it is possible to prevent the extensions 21-24 from cracking when the lid 20 is fitted. Furthermore, compared to an embodiment in which an adhesive is used to fix the case 10 and the lid 20, it is possible to reduce costs by omitting or reducing the use of adhesive. Furthermore, even if the circuit board 70 and the like are sealed with gel G, the length L (height) of the extensions 21-24 can be shortened, so that the height of the board housing areas A1-A3 can be reduced.

[0061] In addition, in this embodiment, the first extension portion 21 and the second extension portion 22 are located at both ends in the longitudinal direction (X direction) of the lid 20, and the convex portion 21a of the first extension portion 21 and the convex portion 22a of the second extension portion 22 protrude away from each other in the longitudinal direction of the lid 20.

[0062] As a result, the convex parts 21a, 22a of the first extension part 21 and the second extension part 22 are hooked to the first hook part 11a and the second hook part 11b from the inside of the housing wall 11 (case 10) (so-called inner hooking). In this way, since the first extension part 21 and the second extension part 22 are located inside the housing wall 11, the size of the semiconductor device 1 in a plan view can be reduced compared to a mode in which the convex parts are hooked to the case 10 from the outside of the housing wall 11 (so-called outer hooking). In addition, by adopting the inner hooking, it is possible to more reliably prevent the hook from coming off due to warping of the lid 20 caused by temperature change, etc., compared to the outer hooking. However, the above-mentioned outer hooking configuration in which the first extension part 21 and the second extension part 22 are hooked to the case 10 from the outside of the housing wall 11 may be adopted. In this case, the convex parts 21a, 22a of the first extension part 21 and the second extension part 22 are provided so as to protrude in a direction approaching each other. Furthermore, the multiple extension portions 21 to 24 may be configured to consist only of the first extension portion 21 and the second extension portion 22, or the first extension portion 21 and the second extension portion 22 may be provided at positions different from both ends in the longitudinal direction (X direction) of the lid 20.

[0063] In addition, in this embodiment, the multiple extension portions 21-24 further include one or more intermediate extension portions (third extension portion 23 and fourth extension portion 24) located between the first extension portion 21 and the second extension portion 22, which are located at both ends in the longitudinal direction (X direction) of the lid 20.

[0064] Therefore, the lid 20 can be hooked onto the case 10 not only at both ends in the longitudinal direction of the lid 20 but also at the middle portion. This makes it difficult for the lid 20 to come off the case 10 even in a situation where the lid 20 warps due to a temperature change or the like or the semiconductor device 1 is subjected to vibration. Therefore, the lid 20 can be more reliably fitted into the case 10.

[0065] In addition, in this embodiment, one or more intermediate extension portions whose positions in the longitudinal direction (X direction) of the lid 20 are located between the first extension portion 21 and the second extension portion 22 include a third extension portion 23 having a protrusion 23a protruding in the second direction (negative side of the X direction) and a fourth extension portion 24 having a protrusion 24a protruding in the first direction (positive side of the X direction).

[0066] This allows the lid 20 to be hooked onto the case 10 in directions away from each other by the convex portion 21a protruding in the first direction (positive side in the X direction) of the first extending portion 21 and the convex portion 23a protruding in the second direction (negative side in the X direction) of the third extending portion 23. Furthermore, the lid 20 can be hooked onto the case 10 in directions away from each other by the convex portion 22a protruding in the second direction (negative side in the X direction) of the second extending portion 22 and the convex portion 24a protruding in the first direction (positive side in the X direction). Therefore, the lid 20 can be fitted into the case 10 more reliably.

[0067] In the present embodiment, the case 10 has a plurality of substrate accommodating regions A1 to A3, and a first partition wall 12 and a second partition wall 13 (an example of one or more partition walls) that separate the plurality of substrate accommodating regions A1 to A3. The plurality of hook portions 11a, 11b, 12a, 13a include a third hook portion 12a and a fourth hook portion 13a (an example of one or more intermediate hook portions) that are provided on the first partition wall 12 and the second partition wall 13 and onto which the protrusions 23a, 24a of the intermediate extension portions (the third extension portion 23 and the fourth extension portion 24) are hooked.

[0068] This allows the protrusions 23a, 24a of the third extending portion 23 and the fourth extending portion 24 to be hooked onto the case 10 (the third hook portion 12a of the first partition wall 12 and the fourth hook portion 13a of the second partition wall 13) with a simple configuration using the first partition wall 12 and the second partition wall 13. This allows the semiconductor device 1 to be further reduced in height and size.

[0069] In addition, in this embodiment, the multiple deformation holes 25a to 25e include, for example, third deformation holes 25c, 25d and fourth deformation holes 25e, 25f (examples of intermediate deformation holes) on both sides of each of the third extension portion 23 and the fourth extension portion 24 (an example of an intermediate extension portion) in the longitudinal direction (X direction) of the lid 20, which reduce the reaction force caused by the deformation of the third extension portion 23 and the fourth extension portion 24.

[0070] Therefore, by narrowing the width of the third extension portion 23 and the fourth extension portion 24 in the longitudinal direction (X direction) of the lid 20 between the third deformation holes 25c and 25d and between the fourth deformation holes 25e and 25f, it is possible to easily flex the third extension portion 23 and the fourth extension portion 24. This allows the length L of the third extension portion 23 and the fourth extension portion 24 in the Z direction to be further shortened, thereby enabling the semiconductor device 1 to be further reduced in height.

[0071] In addition, in this embodiment, in a direction (Y direction) perpendicular to the longitudinal direction (X direction) of the lid 20 and the depth direction (Z direction) of the substrate accommodating areas A1 to A3, the first deformation hole 25a provided on the first extension portion 21 side extends longer (e.g., in a straight line) than the first extension portion 21, and the second deformation hole 25b provided on the second extension portion 22 side extends longer (e.g., in a straight line) than the second extension portion 22.

[0072] As a result, the width of the first extension portion 21 and its front and rear portions in the longitudinal direction (X direction) of the lid 20 is narrowed by the right end (X direction positive end) of the lid 20 and the first deformation hole 25a, making it easier to bend the first extension portion 21. Similarly, the width of the second extension portion 22 and its front and rear portions in the longitudinal direction (X direction) of the lid 20 is narrowed by the left end (X direction negative end) of the lid 20 and the second deformation hole 25b, making it easier to bend the second extension portion 22. As a result, the length L in the Z direction of the first extension portion 21 and the second extension portion 22 can be further shortened, making it possible to further reduce the height of the semiconductor device 1.

[0073] In this embodiment, the first extension portion 21 and the second extension portion 22 located at both ends in the longitudinal direction (X direction) of the lid 20 are provided at positions (recesses 26a, 26b) recessed in the longitudinal direction from both ends in the longitudinal direction (X direction) of the lid 20. In the first modified example of this embodiment, the second deformation hole 25b-1 (similar to the first deformation hole 25a which relieves the reaction force due to the deformation of the first extension portion 21) which relieves the reaction force due to the deformation of the second extension portion 22 is formed along the outer periphery of the lid 20. For example, the second deformation hole 25b-1 extends in a direction (Y direction) perpendicular to the longitudinal direction (X direction) of the lid 20 and the depth direction (Z direction) of the substrate accommodating areas A1 to A3, and is located farther in the longitudinal direction (X direction) of the lid 20 from the convex portion 22a of the second extension portion 22, where the deformation hole 25b-1 relieves the reaction force due to deformation, at the central portion 25b-1c than at both end portions (ends 25b-1a, 25b-1b).

[0074] Therefore, the longitudinal length from the other end (left end) of the lid 20 to the end 25b-1a, the longitudinal length from the recess 26b-1 to the central portion 25b-1c, and the longitudinal length from the other end (left end) of the lid 20 to the end 25b-1b can be made constant, making it easier to flex the second extending portion 22. This allows the length L in the Z direction of the second extending portion 22 (or the first extending portion 21) to be further shortened, thereby enabling the semiconductor device 1 to be made even lower in height.

[0075] In this embodiment, the first deformation hole 25a and the second deformation hole 25b are provided adjacent to the first extending portion 21 and the second extending portion 22.

[0076] Therefore, compared to a configuration in which the first deformation hole 25a and the second deformation hole 25b are not adjacent to the first extension portion 21 and the second extension portion 22, it is easier to bend the first extension portion 21 and the second extension portion 22, and the reaction force due to deformation can be more reliably mitigated.

[0077] In this embodiment, the deformation holes 25a to 25f penetrate the lid 20.

[0078] Therefore, it is possible to easily bend the extensions 21-24 compared to a case where a deformation hole that does not penetrate the lid 20 is used. This allows the length L of the extensions 21-24 in the Z direction to be further shortened, and therefore the semiconductor device 1 can be made even thinner.

[0079] In the second modification of this embodiment, the fourth deformation hole 25f-1 is a depression provided in the surface (bottom surface) of the lid 20 on the side of the substrate accommodating areas A1 to A3.

[0080] This prevents dust and other particles from entering the substrate accommodating areas A1 to A3 through deformation holes that do not penetrate the lid 20, such as the fourth deformation hole 25f-1, unlike the deformation holes 25a to 25f that penetrate the lid 20.

[0081] The invention as described in the claims of the original application is set forth below.

[0082] <Appendix 1> a case for accommodating a circuit board on which a semiconductor element is mounted in a board accommodating area; a lid for covering the substrate receiving area; the lid has a plurality of extensions including a first extension having a convex portion extending toward the substrate accommodating area and protruding in a first direction, and a second extension having a convex portion extending toward the substrate accommodating area and protruding in a second direction opposite to the first direction, and a plurality of deformation holes; The case has a plurality of hook portions to which the protrusions of the extension portions are hooked, A semiconductor device comprising:

[0083] <Appendix 2> The first extension portion and the second extension portion are located at both ends in the longitudinal direction of the lid, The protrusion of the first extension portion and the protrusion of the second extension portion protrude away from each other in the longitudinal direction of the lid. 2. The semiconductor device according to claim 1 .

[0084] <Appendix 3> The plurality of extension portions further include one or more intermediate extension portions whose positions in the longitudinal direction of the lid are located between the first extension portion and the second extension portion. 3. The semiconductor device according to claim 2.

[0085] <Appendix 4> The one or more intermediate extension portions include a third extension portion having the protrusion protruding in the second direction, and a fourth extension portion having the protrusion protruding in the first direction. 4. The semiconductor device according to claim 3.

[0086] <Appendix 5> the case has a plurality of the substrate accommodating regions and one or more partition walls that separate the plurality of substrate accommodating regions; The plurality of hook portions include one or more intermediate hook portions provided on the partition wall and to which the protrusions of the intermediate extension portions are hooked. 4. The semiconductor device according to claim 3.

[0087] <Appendix 6> The plurality of deformation holes include intermediate deformation holes provided on both sides of the intermediate extension portion in the longitudinal direction of the lid. 4. The semiconductor device according to claim 3.

[0088] <Appendix 7> In a direction perpendicular to the longitudinal direction of the lid and the depth direction of the substrate accommodating area, the deformation hole provided on the first extension portion side extends longer than the first extension portion, and the deformation hole provided on the second extension portion side extends longer than the second extension portion. 3. The semiconductor device according to claim 2.

[0089] <Appendix 8> The first extension portion and the second extension portion are provided at positions recessed in the longitudinal direction from both ends of the lid in the longitudinal direction, The deformation hole is formed along the outer periphery of the lid. 3. The semiconductor device according to claim 2.

[0090] <Appendix 9> The plurality of deformation holes are provided adjacent to the first extension portion and the second extension portion. 2. The semiconductor device according to claim 1 ,

[0091] <Appendix 10> The deformation hole penetrates the lid. 2. The semiconductor device according to claim 1 .

[0092] <Appendix 11> The deformation hole is a recess provided on the surface of the lid facing the substrate housing area. 2. The semiconductor device according to claim 1 . [Industrial Applicability]

[0093] INDUSTRIAL APPLICABILITY As described above, the present invention has an effect of enabling a semiconductor device having a lid fitted into a case to have a low profile, and is useful for, for example, a power semiconductor device. [Explanation of symbols]

[0094] 1 Semiconductor device 10 Cases 11 Containment Wall 11a First hook 11b Second hook 11c, 11d, 11e Lid holder 12 First Partition Wall 12a Third hook (middle hook) 13 Second Partition Wall 13a Fourth hook part (middle hook part) 14 Fixing hole 15,16 Positioning holes 20 Lid 21 1st extension part 21a Convex part 22 Second extension part 22a Convex part 23 Third extension part (intermediate extension part) 23a Convex 24 4th extension part (intermediate extension part) 24a Convex 25a First deformation hole 25b Second deformation hole 25b-1 Second deformation hole (first modification) 25b-1a, 25b-1b Ends (first modified example) 25b-1c Central portion (first modified example) 25c, 25d 3rd deformation hole (intermediate deformation hole) 25e, 25f 4th deformation hole (intermediate deformation hole) 25e-1,25e-2 recess 25f-1 4th modification hole (2nd modification) 26a, 26b Recess 26b-1 Recess (first modified example) 30P terminal 40N terminal 50M terminal 60 Control terminal 70 Circuit Board 70a Insulating plate 70b heat sink 70c circuit board 71 Semiconductor Devices 80 Metal Base A1, A2, A3 Board accommodation area G Gel J1,J2 Bonding material

Claims

1. a case for accommodating a circuit board on which a semiconductor element is mounted in a board accommodating area; a lid for covering the substrate accommodation area; The cover has a plurality of extensions including a first extension having a convex portion extending toward the substrate accommodating area and protruding in a first direction, and a second extension having a convex portion extending toward the substrate accommodating area and protruding in a second direction opposite to the first direction, and a plurality of deformation holes; The case has a plurality of hook portions to which the protrusions of the extension portions are hooked. A semiconductor device comprising:

2. The first extension portion and the second extension portion are located at both ends in a longitudinal direction of the lid, The protrusion of the first extension portion and the protrusion of the second extension portion protrude away from each other in the longitudinal direction of the lid.

2. The semiconductor device according to claim 1.

3. The plurality of extension portions further include one or more intermediate extension portions that are located between the first extension portion and the second extension portion in the longitudinal direction of the lid.

3. The semiconductor device according to claim 2.

4. The one or more intermediate extension portions include a third extension portion having the convex portion protruding in the second direction, and a fourth extension portion having the convex portion protruding in the first direction.

4. The semiconductor device according to claim 3.

5. the case has a plurality of the substrate accommodating regions and one or more partition walls that separate the plurality of substrate accommodating regions; The plurality of hook portions include one or more intermediate hook portions provided on the partition wall and to which the protrusions of the intermediate extension portions are hooked.

4. The semiconductor device according to claim 3.

6. The plurality of deformation holes include intermediate deformation holes provided on both sides of the intermediate extension portion in the longitudinal direction of the lid.

4. The semiconductor device according to claim 3.

7. In a direction perpendicular to the longitudinal direction of the lid and the depth direction of the substrate accommodating area, the deformation hole provided on the first extension portion side extends longer than the first extension portion, and the deformation hole provided on the second extension portion side extends longer than the second extension portion.

3. The semiconductor device according to claim 2.

8. The first extension portion and the second extension portion are provided at positions recessed in the longitudinal direction from both ends of the lid in the longitudinal direction, The deformation hole is formed along the outer periphery of the lid.

3. The semiconductor device according to claim 2.

9. The plurality of deformation holes are provided adjacent to the first extension portion and the second extension portion.

2. The semiconductor device according to claim 1,

10. The deformation hole penetrates the lid.

2. The semiconductor device according to claim 1.

11. The deformation hole is a recess provided on the surface of the lid facing the substrate housing area.

2. The semiconductor device according to claim 1.

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