Semiconductor module

Abstract

The present invention prevents deformation of an insulating component that insulates a positive terminal and a negative terminal.　This semiconductor module has a terminal structure (15a) that includes: a positive terminal (12a); a negative terminal (13a); and a first insulating component (14a) that is sandwiched between the positive terminal (12a) and the negative terminal (13a) and that includes a protruding part which protrudes from between the positive terminal (12a) and the negative terminal (13a). The semiconductor module further includes: a second insulating component (18) and a third insulating component (19) which sandwich the terminal structure (15a) vertically and cover the front surface and the rear surface of at least a portion of the protruding part; and a case integrally formed with the terminal structure (15a) which is sandwiched between the second insulating component (18) and the third insulating component (19).

Description

Semiconductor Module

[0001] The present invention relates to a semiconductor module including a switching element.

[0002] Semiconductor modules including switching elements such as IGBTs (Insulated Gate Bipolar Transistors) and power MOSFETs (Metal Oxide Semiconductor Field Effect Transistors) are used in power conversion devices that use high voltages and large currents. To reduce the inductance of semiconductor modules, some modules have a structure in which the positive terminal and the negative terminal (or the wire connected to the positive terminal and the wire connected to the negative terminal) are placed close to each other with an insulating member such as insulating paper sandwiched between them.

[0003] Such structures are shown, for example, in paragraph

[0096] of Patent Document 1, paragraph

[0021] of Patent Document 2, paragraph

[0046] of Patent Document 3, Figure 4(a), paragraph

[0019] of Patent Document 4, Figure 1(a), paragraph

[0012] of Patent Document 5, Figure 1, paragraph

[0018] of Patent Documents 6 and 7, Figure 5, paragraph

[0033] of Patent Document 8, Figure 1, paragraph

[0018] of Patent Document 9, Figure 2, paragraph

[0162] of Patent Documents 10 and 11, Figure 36(A), paragraph

[0023] , Figure 9 of Patent Document 12, paragraph

[0054] , Figure 34 of Patent Document 13, etc.

[0004] JP 2020-9834 A JP 2016-66974 A JP 2013-9501 A JP 2006-86438 A WO 2022 / 091288 JP 2021-106235 A JP 2022-6876 A WO 2019 / 098368 JP 2016-6834 A JP 2009-81993 A JP 2008-29117 A JP 2010-157565 A WO 2020 / 035931

[0005] To ensure an insulating distance between the positive and negative terminals and prevent dielectric breakdown, the width of the insulating member sandwiched between the positive and negative terminals is sometimes made wider than the width of the positive and negative terminals. In this case, the insulating member has a protruding portion that protrudes from between the positive and negative terminals. When a terminal structure in which an insulating member having such a protruding portion is sandwiched between the positive and negative terminals is integrally molded with a semiconductor module case, the protruding portion may become deformed. Examples of deformation include bending or curling of the protruding portion due to the influence of resin pressure. Such deformation can make it impossible to ensure an insulating distance between the positive and negative terminals, potentially resulting in a deterioration in insulation performance.

[0006] Furthermore, when a thin material such as insulating paper is used as the insulating member, the insulating member is more likely to deform, and it may take time to fix the terminal structure to the mold during integral molding.

[0007] The present invention has been made in view of the above points, and has an object to provide a semiconductor module that can suppress deformation of an insulating member that insulates a positive terminal from a negative terminal.

[0008] According to one aspect of the present invention, there is provided a semiconductor module comprising: a terminal structure having a positive terminal electrically connected to a positive electrode end of a first switching element of an upper arm, a negative terminal electrically connected to a negative electrode end of a second switching element of a lower arm, and a first insulating member sandwiched between the positive terminal and the negative terminal and including a protruding portion, a portion of which protrudes from between the positive terminal and the negative terminal; second and third insulating members sandwiching the terminal structure from above and below and covering front and back surfaces of at least a portion of the protruding portion; and a case molded integrally with the terminal structure sandwiched between the second and third insulating members.

[0009] At least one of the second insulating member and the third insulating member may have a recess on a surface facing the terminal structure, into which the positive terminal or the negative terminal is fitted.

[0010] One of the second insulating member and the third insulating member may have a first protrusion on a surface facing the terminal structure, the first protrusion positioning the first insulating member.

[0011] The plurality of first protrusions may be disposed opposite a part of an outer edge of the first insulating member.

[0012] One of the second insulating member or the third insulating member may have one or more pillars on a first side of the surface facing the terminal structure and on a second side opposite the first side, and the other of the second insulating member or the third insulating member may have a fitting portion that fits with the one or more pillars.

[0013] One of the second insulating member or the third insulating member may have one or more second protrusions on a third edge located toward the inside of the case on the surface facing the terminal structure, and at least a portion of the other side of the second insulating member or the third insulating member may abut against the one or more second protrusions.

[0014] A corner of the protrusion of the first insulating member that is positioned toward the outside of the case may not be sandwiched between the second insulating member and the third insulating member and may extend to the outside of the case.

[0015] An end portion of the protruding portion of the first insulating member facing outward from the case may be covered by the second insulating member and the third insulating member, and may extend outward from the case.

[0016] The case, the second insulating member, and the third insulating member may be made of a thermoplastic resin.

[0017] The first insulating member may be insulating paper.

[0018] The above summary of the invention does not list all of the necessary features of the present invention, and subcombinations of these features may also constitute inventions.

[0019] According to the disclosed technique, deformation of the insulating member that insulates the positive terminal and the negative terminal can be suppressed. The above and other objects, features, and advantages of the present invention will become apparent from the following description taken in conjunction with the accompanying drawings which illustrate preferred embodiments of the present invention as examples.

[0020] 1 is a perspective view showing an example of a semiconductor module according to a first embodiment; FIG. 2 is a diagram showing an example of an equivalent circuit of the semiconductor module according to the first embodiment; FIG. 3 is a perspective view showing an example of a terminal structure; FIG. 4 is a perspective view showing an example of a terminal structure sandwiched between a second insulating member and a third insulating member; FIG. 5 is a perspective view showing an example of a second insulating member; FIG. 6 is a diagram showing an example of an arrangement of a positive terminal on the second insulating member; FIG. 7 is a diagram showing an example of an arrangement of a first insulating member on the second insulating member; FIG. 8 is a diagram showing an example of an arrangement of a negative terminal; FIG. 9 is a perspective view showing an example of a third insulating member; FIG. 10 is a perspective view showing an example of a rear surface of the third insulating member; FIG. 11 is a perspective view showing a modified example of the second insulating member; FIG. 12 is a perspective view showing a modified example of the positive terminal; FIG. 13 is a diagram showing an example of an arrangement of a positive terminal on a modified second insulating member; FIG. 14 is a diagram showing an example of an arrangement of a first insulating member on a modified second insulating member; FIG. 15 is a perspective view showing a modified negative terminal; FIG. 16 is a diagram showing an example of an arrangement of a negative terminal when a modified second insulating member is used; FIG. 17 is a diagram showing an example of an arrangement of a third insulating member when a modified second insulating member is used;

[0021] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description, the terms "front surface" and "top surface" refer to the surface facing upward in the semiconductor module 10 of FIG. 1. Similarly, "top" refers to the upward direction in the semiconductor module 10 of FIG. 1. The terms "back surface" and "bottom surface" refer to the surface facing downward in the semiconductor module 10 of FIG. 1. Similarly, "bottom" refers to the downward direction in the semiconductor module 10 of FIG. 1. Similar directions will be used in other drawings as necessary. The terms "front surface," "top surface," "top," "back surface," "bottom surface," "bottom," and "side surface" are merely convenient expressions for specifying relative positional relationships and do not limit the technical concept of the present invention. For example, "top" and "bottom" do not necessarily refer to the vertical direction relative to the ground. In other words, the "top" and "bottom" directions are not limited to the direction of gravity.

[0022] First Embodiment FIG. 1 is a perspective view showing an example of a semiconductor module according to a first embodiment. FIG. 2 is a diagram showing an example of an equivalent circuit of the semiconductor module according to the first embodiment. FIG. 3 is a perspective view showing an example of a terminal structure. A semiconductor module 10 includes three semiconductor units (not shown) and a case 11 for accommodating the semiconductor units. The semiconductor units include a ceramic circuit board and a semiconductor chip mounted on the ceramic circuit board. The ceramic circuit board includes an insulating plate, a heat sink formed on the back surface of the insulating plate, and a circuit pattern formed on the front surface of the insulating plate. The insulating plate is made of a ceramic with excellent thermal conductivity. Such ceramics include high-temperature conductive aluminum oxide, aluminum nitride, silicon nitride, etc. The heat sink is made of a metal with excellent thermal conductivity. Such metals include aluminum, iron, silver, copper, or an alloy containing at least one of these. The circuit pattern is made of a metal with excellent electrical conductivity. Such metals include copper or a copper alloy. The number and shape of the circuit patterns are appropriately selected depending on the specifications of the semiconductor module 10. As a ceramic circuit board having such a configuration, for example, a DCB (Direct Copper Bonding) board or an AMB (Active Metal Brazed) board can be used.

[0023] The semiconductor chip includes a switching element such as a power MOSFET or an IGBT, which is made of silicon or silicon carbide. Such a semiconductor chip includes, for example, a drain electrode (or collector electrode) as a main electrode on the back surface and a gate electrode and a source electrode (or emitter electrode) as main electrodes on the front surface. The semiconductor chip also includes, as necessary, a free-wheeling diode (FWD) such as a Schottky barrier diode (SBD) or a P-intrinsic-N (PiN) diode. Such a semiconductor chip includes a cathode electrode as a main electrode on the back surface and an anode electrode as a main electrode on the front surface. Alternatively, a reverse-conducting (RC) IGBT, which combines the functions of an IGBT and an FWD, may be used as the semiconductor chip. The number and type of such semiconductor chips are also selected appropriately depending on the specifications of the semiconductor module 10.

[0024] The case 11 includes storage areas 11c1, 11c2, and 11c3 for storing the semiconductor units described above. The storage areas 11c1, 11c2, and 11c3 are spaces provided in the middle of the case 11 along the longitudinal direction of the case 11 in a plan view. The semiconductor units are electrically connected to various terminals, as described below, within the storage areas 11c1, 11c2, and 11c3. For this electrical connection, wiring members such as bonding wires and lead frames are used. The wiring members are made of a material with excellent conductivity. Such a material is a metal such as aluminum or copper, or an alloy containing at least one of these metals.

[0025] The case 11 further includes terminal structures 15a, 15b, and 15c. The terminal structure 15a includes a positive terminal 12a, a negative terminal 13a, and a first insulating member 14a sandwiched between the positive terminal 12a and the negative terminal 13a. The terminal structure 15b includes a positive terminal 12b, a negative terminal 13b, and a first insulating member 14b sandwiched between the positive terminal 12b and the negative terminal 13b. The terminal structure 15c includes a positive terminal 12c, a negative terminal 13c, and a first insulating member 14c sandwiched between the positive terminal 12c and the negative terminal 13c.

[0026] The positive terminals 12a, 12b, 12c and the negative terminals 13a, 13b, 13c are made of a metal with excellent conductivity. Such a metal is, for example, copper or a copper alloy. One end of the front surface of each of the positive terminals 12a, 12b, 12c and the negative terminals 13a, 13b, 13c is exposed along the longitudinal direction on the first side 11a of the case 11, as shown in FIG. 1 . The positive terminals 12a, 12b, 12c and the negative terminals 13a, 13b, 13c are each flat on at least the first side 11a side. Wiring electrically connecting a capacitor functioning as a power source to the semiconductor unit is connected to the exposed portions of the positive terminals 12a, 12b, 12c and the negative terminals 13a, 13b, 13c. The other ends of the positive terminals 12 a , 12 b , and 12 c and the negative terminals 13 a , 13 b , and 13 c are electrically connected to the semiconductor unit inside the case 11 .

[0027] In the equivalent circuit of FIG. 2, the positive terminals 12a, 12b, and 12c are denoted as P(12a), P(12b), and P(12c). The negative terminals 13a, 13b, and 13c are denoted as N(13a), N(13b), and N(13c). The positive terminal 12a of the terminal structure 15a is electrically connected to the positive terminal of the first switching element 21a1 of the upper arm, as shown in FIG. 2, of the semiconductor unit housed in the storage region 11c1. The negative terminal 13a of the terminal structure 15a is electrically connected to the negative terminal of the second switching element 21a2 of the lower arm, as shown in FIG. 2, of the semiconductor unit housed in the storage region 11c1. For example, if the first switching element 21a1 and the second switching element 21a2 are IGBTs, the positive terminal is the collector electrode of the first switching element 21a1, and the negative terminal is the emitter electrode of the second switching element 21a2.

[0028] Similarly, the positive terminal 12b of the terminal structure 15b is electrically connected to the positive terminal of the first switching element 21b1 of the upper arm (as shown in FIG. 2) of the semiconductor unit housed in the storage region 11c2. The negative terminal 13b of the terminal structure 15b is electrically connected to the negative terminal of the second switching element 21b2 of the lower arm (as shown in FIG. 2) of the semiconductor unit housed in the storage region 11c2. Similarly, the positive terminal 12c of the terminal structure 15c is electrically connected to the positive terminal of the first switching element 21c1 of the upper arm (as shown in FIG. 2) of the semiconductor unit housed in the storage region 11c3. The negative terminal 13c of the terminal structure 15c is electrically connected to the negative terminal of the second switching element 21c2 of the lower arm (as shown in FIG. 2) of the semiconductor unit housed in the storage region 11c3.

[0029] The first insulating members 14a, 14b, and 14c are, for example, insulating paper. Examples of insulating paper that can be used include insulating paper made of a wholly aromatic polyamide polymer, and sheet-shaped insulating paper made of a fluorine-based or polyimide-based resin material. The first insulating members 14a, 14b, and 14c may also be ceramic substrates made of aluminum oxide or silicon nitride. The tips of the first insulating members 14a, 14b, and 14c on the first side 11a are located between the tips of the positive terminals 12a, 12b, and 12c and the tips of the negative terminals 13a, 13b, and 13c. This maintains insulation between the positive terminals 12a, 12b, and 12c and the negative terminals 13a, 13b, and 13c.

[0030] 3, in the terminal structure 15a, openings 12a1 and 13a1 are provided in the positive terminal 12a and the negative terminal 13a. The openings 12a1 and 13a1 are holes through which positioning pins extending from a mold used in integrally molding the case 11 pass. A portion 12a2 of the positive terminal 12a extends from the back surface of the first insulating member 14a toward the inside of the case 11. A step is provided in the portion 12a2. For example, the lowest step at the tip of the portion 12a2 is connected to the positive electrode of the semiconductor unit via a wiring member such as a bonding wire or a lead frame.

[0031] The negative terminal 13a is divided into two portions 13a2 and 13a3 on the first insulating member 14a toward the inside of the case 11. The portions 13a2 and 13a3 extend from the front surface of the first insulating member 14a toward the inside of the case 11. The portions 13a2 and 13a3 are provided with steps. For example, the lowest steps at the tips of the portions 13a2 and 13a3 are connected to the negative electrode of the semiconductor unit via wiring members such as bonding wires or lead frames.

[0032] The width of the first insulating member 14a (the length in the longitudinal direction of the case 11) is wider than the width of the positive terminal 12a and the negative terminal 13a in order to ensure an insulating distance between the positive terminal 12a and the negative terminal 13a and prevent dielectric breakdown. Therefore, a part of the first insulating member 14a forms a protrusion 14a1 that protrudes from between the positive terminal 12a and the negative terminal 13a.

[0033] The terminal structures 15b and 15c have the same configuration as the terminal structure 15a shown in FIG.

[0034] 3 may be deformed and the insulating performance may be reduced when the terminal structure 15a and the case 11 are integrally molded. Furthermore, when a thin material such as insulating paper is used as the first insulating member 14a, the first insulating member 14a is more likely to deform, and it may take time to fix the terminal structure 15a to the mold during integral molding.

[0035] Therefore, in the semiconductor module 10 of the first embodiment, each of the above-mentioned terminal structures 15a, 15b, and 15c is sandwiched from above and below by a second insulating member and a third insulating member that cover at least a portion of the front and back surfaces of the above-mentioned protrusions.

[0036] 4 is a perspective view showing an example in which the terminal structure is sandwiched between the second insulating member and the third insulating member. The second insulating member 18 and the third insulating member 19 sandwich the terminal structure 15a from above and below, covering at least a portion of the front and rear surfaces of the protruding portion of the first insulating member 14a (e.g., the protruding portion 14a1 in FIG. 3 ). The terminal structure 15a is molded integrally with the case 11 while being sandwiched between the second insulating member 18 and the third insulating member 19 in this manner. Although not shown, the terminal structures 15b and 15c are also molded integrally with the case 11 while being sandwiched between the second insulating member and the third insulating member in a similar manner.

[0037] This suppresses deformation of the protruding portions of the first insulating members 14a, 14b, and 14c during molding, preventing degradation of insulating performance. Furthermore, suppressing deformation of the protruding portions of the first insulating members 14a, 14b, and 14c shortens the time required to fix the terminal structures 15a, 15b, and 15c to a mold during integral molding. Furthermore, pins or other components for suppressing deformation of the protruding portions of the first insulating members 14a, 14b, and 14c are no longer required in the mold, simplifying the mold configuration. The second insulating member 18 and the third insulating member 19 are made of a thermoplastic resin, similar to the material of the case 11. This prevents resin from flowing into the terminal structure 15a during integral molding. Specific configuration examples of the second insulating member 18 and the third insulating member 19 will be described later (see FIGS. 5, 9, and 10).

[0038] As shown in FIG. 1 , the case 11 further includes control terminals 16a, 16b, and 16c attached to the sides of the storage areas 11c1, 11c2, and 11c3, respectively. The control terminals 16a, 16b, and 16c are made of a metal with excellent conductivity, such as copper, copper alloy, aluminum, or aluminum alloy. The control terminal 16a is electrically connected to the gate terminal of the first switching element 21a1 or the second switching element 21a2 (shown in FIG. 2 ) of the semiconductor unit housed in the storage area 11c1. The control terminal 16b is electrically connected to the gate terminal of the first switching element 21b1 or the second switching element 21b2 (shown in FIG. 2 ) of the semiconductor unit housed in the storage area 11c2. The control terminal 16c is electrically connected to the gate terminal of the first switching element 21c1 or the second switching element 21c2 (shown in FIG. 2 ) of the semiconductor unit housed in the storage area 11c3.

[0039] Furthermore, case 11 includes U terminal 17a, V terminal 17b, and W terminal 17c. One end of U terminal 17a, V terminal 17b, and W terminal 17c is exposed on second side 11b of case 11 along the longitudinal direction of case 11. U terminal 17a, V terminal 17b, and W terminal 17c are made of a metal with excellent conductivity. Such a metal is, for example, copper or a copper alloy. The other end of U terminal 17a, V terminal 17b, and W terminal 17c is electrically connected to the semiconductor unit inside case 11 as follows.

[0040] In the equivalent circuit of FIG. 2, the U terminal 17a, V terminal 17b, and W terminal 17c are denoted as U(17a), V(17b), and W(17c). The U terminal 17a is electrically connected to the negative terminal of the first switching element 21a1 and the positive terminal of the second switching element 21a2 (shown in FIG. 2) of the semiconductor unit housed in the storage area 11c1. The V terminal 17b is electrically connected to the negative terminal of the first switching element 21b1 and the positive terminal of the second switching element 21b2 (shown in FIG. 2) of the semiconductor unit housed in the storage area 11c2. The W terminal 17c is electrically connected to the negative terminal of the first switching element 21c1 and the positive terminal of the second switching element 21c2 (shown in FIG. 2) of the semiconductor unit housed in the storage area 11c3.

[0041] The case 11 is integrally molded with the terminal structures 15a, 15b, and 15c, the control terminals 16a, 16b, and 16c, the U terminal 17a, the V terminal 17b, and the W terminal 17c, which are sandwiched between the second and third insulating members. The molding is performed by injection molding using a thermoplastic resin, for example. Examples of the thermoplastic resin include polyphenylene sulfide (PPS) resin, polybutylene terephthalate (PBT) resin, polybutylene succinate (PBS) resin, polyamide (PA) resin, and acrylonitrile butadiene styrene (ABS) resin.

[0042] Furthermore, semiconductor units are housed in the housing regions 11c1, 11c2, and 11c3, and after electrical connections are made with the various terminals, the interior of the case 11 is sealed with a sealing resin. The sealing material contains a thermosetting resin and a filler contained in the thermosetting resin. The thermosetting resin is an epoxy resin, a phenolic resin, a maleimide resin, or the like. The filler is silicon oxide, aluminum oxide, boron nitride, or aluminum nitride.

[0043] Although the semiconductor module 10 has been described above as including three semiconductor units, the present invention is not limited to this and the semiconductor module 10 may include one, two, or four or more semiconductor units.

[0044] Next, examples of the second insulating member and the third insulating member that sandwich each of the terminal structures 15 a, 15 b, and 15 c from above and below will be described in more detail. Note that, although the following description focuses on an example of the second insulating member and the third insulating member that sandwich the terminal structure 15 a from above and below, the second insulating member and the third insulating member that sandwich the terminal structures 15 b and 15 c from above and below have the same configuration.

[0045] FIG. 5 is a perspective view showing an example of a second insulating member. The surface of the second insulating member 18 facing the terminal structure 15a is provided with a recess 18a into which the positive terminal 12a is fitted. Furthermore, the surface of the second insulating member 18 facing the terminal structure 15a is provided with first protrusions 18b1 and 18b2 for positioning the first insulating member 14a. The first protrusions 18b1 and 18b2 are positioned opposite a portion of the outer edge of the first insulating member 14a (see FIG. 7 ). Furthermore, the surface of the second insulating member 18 facing the terminal structure 15a is provided with support posts 18c1 and 18c2 on a first side, and support posts 18c3 and 18c4 on a second side opposite the first side. The number of support posts is not limited to two on each of the first and second sides, and may be one, three, or more.

[0046] Fig. 6 is a diagram showing an example of the arrangement of the positive terminal on the second insulating member 18. As shown in Fig. 6, a portion of the positive terminal 12a is fitted into the recess 18a of the second insulating member 18. This prevents the positive terminal 12a from shifting out of position.

[0047] 7 shows an example of the arrangement of the first insulating member on the second insulating member. The first insulating member 14a is arranged on a portion of the upper surface of the positive terminal 12a, which is fitted into the recess 18a of the second insulating member 18. The first protrusions 18b1 and 18b2 of the second insulating member 18 protrude toward the inside of the first insulating member 14a to engage with the side edges of the first insulating member 14a. The side surfaces of the side edges of the first insulating member 14a facing the first protrusions 18b1 and 18b2 are recessed inward. The first insulating member 14a is positioned by the first protrusions 18b1 and 18b2 of the second insulating member 18. This prevents the first insulating member 14a from shifting out of position.

[0048] 8 shows an example of the arrangement of the negative terminal 13a. The negative terminal 13a is arranged on the front surface of the first insulating member 14a. As described above, the portions 13a2 and 13a3 extend from the front surface of the first insulating member 14a toward the inside of the case 11.

[0049] 9 is a perspective view showing an example of a third insulating member. The third insulating member 19 has fitting portions 19a1 and 19a2 that fit with the support posts 18c2 and 18c3 of the second insulating member 18. By providing such fitting portions 19a1 and 19a2, it is possible to suppress misalignment of the third insulating member 19 in the longitudinal direction of the case 11 and in the outward direction of the case 11. The third insulating member 19 also has protrusions 19b1 and 19b2 that abut against the support posts 18c1 and 18c4 of the second insulating member 18 in the longitudinal direction of the case 11. By providing such protrusions 19b1 and 19b2, it is possible to further suppress misalignment of the third insulating member 19 in the longitudinal direction of the case 11.

[0050] 10 is a perspective view showing an example of the back surface of the third insulating member 19. The back surface of the third insulating member 19 (the surface facing the terminal structure 15a) is provided with a recess 19c into which the negative terminal 13a is fitted. This prevents the negative terminal 13a from shifting out of position.

[0051] In the above example, both the second insulating member 18 and the third insulating member 19 have recesses 18a and 19c into which the positive terminal 12a and the negative terminal 13a are fitted, but this is not limited thereto. One of the second insulating member 18 and the third insulating member 19 may have a recess into which the positive terminal 12a or the negative terminal 13a is fitted. In the above example, the second insulating member 18 has first protrusions 18b1 and 18b2 for positioning the first insulating member 14a, but this is not limited thereto. The third insulating member 19 may have a first protrusion for positioning the first insulating member 14a on its surface facing the terminal structure 15a (its back surface shown in FIG. 10 ). In the above example, the second insulating member 18 has supports 18c1 to 18c4, and the third insulating member 19 has fitting portions 19a1 and 19a2 and protrusions 19b1 and 19b2, but this is not limited thereto. The third insulating member 19 may be provided with pillars similar to the pillars 18c1 to 18c4, and the second insulating member 18 may be provided with fitting portions and protrusions similar to the fitting portions 19a1, 19a2 and protrusions 19b1, 19b2.

[0052] 11 to 17, elements similar to those shown in FIGS. 5 to 9 are denoted by the same reference numerals. FIG. 11 is a perspective view showing a modified second insulating member. Similar to second insulating member 18, modified second insulating member 30 has supports 18c1 and 18c2 on a first side of the surface facing terminal structure 15a and supports 18c3 and 18c4 on a second side facing the first side. Furthermore, modified second insulating member 30 has second protrusions 30a1 and 30a2 on a third side of the surface facing terminal structure 15a, the third side being located toward the inside of case 11.

[0053] A portion of the second protrusions 30a1 and 30a2 is provided on the recess 18a. Fig. 12 is a perspective view showing a modified example of the positive terminal. The positive terminal 12a is provided with recesses 12a3 and 12a4 that fit into the portions of the second protrusions 30a1 and 30a2 shown in Fig. 11 that are formed on the recess 18a of the second insulating member 30.

[0054] Fig. 13 is a diagram showing an example of arrangement of the positive terminal on the second insulating member of a modified example. The positive terminal 12a is fitted into the recess 18a of the second insulating member 30. Furthermore, the recesses 12a3 and 12a4 of the positive terminal 12a as shown in Fig. 12 are fitted into parts of the second protrusions 30a1 and 30a2. This prevents the positive terminal 12a from shifting position.

[0055] 14 is a diagram showing an example of the arrangement of the first insulating member on the second insulating member of the modified example. The first insulating member 14a is arranged on a portion of the upper surface of the positive terminal 12a, which is fitted into the recess 18a of the second insulating member 30. The first insulating member 14a is positioned by the first protrusions 18b1 and 18b2 of the second insulating member 30. Furthermore, the side surface of the first insulating member 14a facing the inside of the case 11 abuts against the second protrusions 30a1 and 30a2. This prevents the first insulating member 14a from shifting in position toward the inside of the case 11.

[0056] FIG. 15 is a perspective view showing a modified negative terminal. The negative terminal 13a has recesses 13a4 and 13a5 that fit onto the second protrusions 30a1 and 30a2 shown in FIG. 11. FIG. 16 is a diagram showing an example of the arrangement of the negative terminal when a modified second insulating member is used. The negative terminal 13a is arranged on the front surface of the first insulating member 14a. When the second insulating member 30 is used, the recesses 13a4 and 13a5 of the negative terminal 13a as shown in FIG. 15 fit onto the second protrusions 30a1 and 30a2. This prevents the negative terminal 13a from shifting out of position.

[0057] 17 shows an example of the arrangement of the third insulating member when a modified second insulating member is used. Part of the side surface of the third insulating member 31 abuts against the second protrusions 30a1 and 30a2. This prevents the third insulating member 31 from shifting in position toward the inside of the case 11.

[0058] In the above example, the second insulating member 30 includes the second protrusions 30a1 and 30a2, but the third insulating member 31 may include second protrusions similar to the second protrusions 30a1 and 30a2. In this case, at least a part of the side surface of the second insulating member 30 abuts against the second protrusions provided on the third insulating member 31.

[0059] Second Embodiment Fig. 18 is a perspective view showing an example of a semiconductor module according to a second embodiment. Fig. 19 is a perspective view showing an example of a terminal structure sandwiched between a second insulating member and a third insulating member. In Figs. 18 and 19, the same elements as those shown in Figs. 1 and 17 are designated by the same reference numerals.

[0060] 4 , in the semiconductor module 10 of the first embodiment described above, the corners of the protrusion 14a1 of the first insulating member 14a located on the outer side of the case 11 are not sandwiched between the second insulating member 18 and the third insulating member 19, and extend outward from the case 11. In contrast, in the semiconductor module 40 of the second embodiment, the ends 14a2 and 14a3 of the protrusion of the first insulating member 14a on the outer side of the case 11 are covered by the second insulating member 50 and the third insulating member 51, and extend outward from the case 11. This further suppresses deformation of the protrusion 14a1 of the first insulating member 14a, preventing a decrease in insulation performance.

[0061] In the example of Figure 19, the second insulating member 50 has second protrusions 30a1 and 30a2 as shown in Figure 11, but it does not have to have second protrusions 30a1 and 30a2 like the second insulating member 18 shown in Figure 5.

[0062] Although one aspect of the semiconductor module of the present invention has been described above based on the embodiment, these are merely examples and are not intended to be limiting. For example, the positive terminals 12a, 12b, and 12c may be negative terminals connected to the negative terminals of the second switching elements of the lower arm, and the negative terminals 13a, 13b, and 13c may be positive terminals connected to the positive terminals of the first switching elements of the upper arm. That is, although the lower terminals of the terminal structures 15a, 15b, and 15c are described as positive terminals and the upper terminals as negative terminals in the above example, the positive and negative terminals may be reversed. The above merely illustrates the principles of the present invention. Furthermore, since numerous modifications and variations are possible to those skilled in the art, the present invention is not limited to the exact configurations and applications shown and described above. All corresponding modifications and equivalents are deemed to be within the scope of the present invention as defined by the appended claims and their equivalents.

[0063] 10, 40 Semiconductor module 11 Case 11a First side portion 11b Second side portion 11c1 to 11c3 Storage area 12a, 12b, 12c Positive terminal 12a1, 13a1 Opening 12a2, 13a2, 13a3 Portion 12a3, 12a4, 13a4, 13a5 Recess 13a, 13b, 13c Negative terminal 14a, 14b, 14c First insulating member 14a1 Protrusion 14a2, 14a3 End 15a, 15b, 15c Terminal structure 16a, 16b, 16c Control terminal 17a U terminal 17b V terminal 17c W terminal 21a1, 21b1, 21c1 First switching element 21a2, 21b2, 21c2 Second switching element 18, 30, 50 Second insulating member 18a Recess 18b1, 18b2 First protrusion 18c1 to 18c4 Support 19, 31, 51 Third insulating member 19a1, 19a2 Fitting portion 19b1, 19b2 Protrusion 19c Recess 30a1, 30a2 Second protrusion

Claims

1. A semiconductor module comprising: a terminal structure having a positive terminal electrically connected to the positive electrode end of a first switching element of an upper arm, a negative terminal electrically connected to the negative electrode end of a second switching element of a lower arm, and a first insulating member sandwiched between the positive terminal and the negative terminal and including a protruding portion, a portion of which protrudes from between the positive terminal and the negative terminal; second and third insulating members sandwiching the terminal structure from above and below and covering the front and back surfaces of at least a portion of the protruding portion; and a case molded integrally with the terminal structure sandwiched between the second and third insulating members.

2. The semiconductor module according to claim 1, wherein at least one of the second insulating member and the third insulating member has a recess on the surface facing the terminal structure into which the positive terminal or the negative terminal is fitted.

3. The semiconductor module according to claim 1, wherein one of the second insulating member and the third insulating member has a first protrusion on a surface facing the terminal structure, the first protrusion positioning the first insulating member.

4. The semiconductor module according to claim 3, wherein the plurality of first protrusions are arranged opposite to a portion of the outer edge of the first insulating member.

5. The semiconductor module according to claim 1, wherein one of the second insulating member or the third insulating member has one or more support posts on a first side and a second side opposite the first side of a surface facing the terminal structure, and the other of the second insulating member or the third insulating member has a fitting portion that fits into the one or more support posts.

6. The semiconductor module according to claim 1, wherein one of the second insulating member or the third insulating member has one or more second protrusions on a third edge located toward the inside of the case on a surface facing the terminal structure, and at least a portion of the other side surface of the second insulating member or the third insulating member abuts against the one or more second protrusions.

7. A semiconductor module as described in claim 1, wherein a corner of the protrusion of the first insulating member located toward the outside of the case is not sandwiched between the second insulating member and the third insulating member and extends outside the case.

8. A semiconductor module as described in claim 1, wherein the end of the protrusion of the first insulating member facing outward from the case is covered by the second insulating member and the third insulating member and extends outward from the case.

9. The semiconductor module according to claim 1, wherein the case, the second insulating member, and the third insulating member are made of a thermoplastic resin.

10. The semiconductor module according to claim 1, wherein the first insulating member is insulating paper.

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