Semiconductor Module

Abstract

To enable an assembly of a semiconductor module using a member of one specification even for a plurality of substrates having different plate thicknesses.SOLUTION: A first stepped surface (41) and a second stepped surface (42) are provided on an inner surface side of a peripheral wall (32) of a case (30). The second stepped surface (42) extends parallel to the first stepped surface (41) on at least one of the outer side and the inner side of a substrate (10) with respect to the first stepped surface (41). In the second stepped surface (42) provided on the outer side of the substrate (10) with respect to the first stepped surface (41), a distance from a reference end surface (43) to the second stepped surface (42) is shorter than the distance from the reference end surface (43) to the first stepped surface (41). In the second stepped surface (42) provided inside the substrate (10) from the first stepped surface (41), the distance from the reference end surface (43) to the second stepped surface (42) is longer than the distance from the reference end surface (43) to the first stepped surface (41).SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present disclosure relates to a semiconductor module. [Background technology]

[0002] Patent Document 1 discloses a power semiconductor module including a base plate on which an insulating substrate is disposed, a case surrounding the insulating substrate and the base plate, and a spacer provided between the outer periphery of the base plate and the inner periphery of the case in contact with both. The document states that providing the spacer enables the same size case to be used for base plates of various sizes. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6391527 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the invention of Patent Document 1, in order to use the same size case, it is necessary to produce multiple spacers corresponding to base plates of various sizes, which increases the number of spacer specifications, resulting in problems such as reduced production efficiency and complicated inventory management.

[0005] An object of the present disclosure is to enable a semiconductor module to be assembled using members of a single specification even for a plurality of substrates having different thicknesses. [Means for solving the problem]

[0006] A first aspect of the present disclosure is a semiconductor module including a substrate (10) and a case (30) that covers a mounting surface (11) of the substrate (10), wherein the case (30) has a facing portion (31) that faces the mounting surface (11) of the substrate (10) and a peripheral wall portion (32) that extends toward the substrate (10) along the periphery of the facing portion (31), and the inner surface of the peripheral wall portion (32) is provided with a first step surface (41) that abuts against the mounting surface (11) of the substrate (10) and a second step surface (41) that extends parallel to the first step surface (41) at least on one of the outer side and the inner side of the substrate (10) relative to the first step surface (41). 2), and when the second step surface (42) is provided outside the substrate (10) relative to the first step surface (41), the distance from a reference end surface (43) on the peripheral wall portion (32) opposite the opposing portion (31) to the second step surface (42) is shorter than the distance from the reference end surface (43) to the first step surface (41), and when the second step surface (42) is provided inside the substrate (10) relative to the first step surface (41), the distance from the reference end surface (43) to the second step surface (42) is longer than the distance from the reference end surface (43) to the first step surface (41).

[0007] In the first aspect, if a case (30) of one specification having a first step surface (41) and a second step surface (42) is produced, a semiconductor module can be assembled, for example, for a plurality of substrates (10) having different thicknesses, by abutting the mounting surface (11) of the substrate (10) against either the first step surface (41) or the second step surface (42).

[0008] A second aspect of the present disclosure is a semiconductor module of the first aspect, wherein the first step surface (41) and the second step surface (42) are provided with groove portions (45) extending circumferentially of the peripheral wall portion (32).

[0009] In the second aspect, by filling the groove portion (45) with adhesive to bond the case (30) and the substrate (10), it is possible to prevent the adhesive from spilling out from between the mounting surface (11) of the substrate (10) and the first step surface (41) or the second step surface (42).

[0010] In a third aspect of the present disclosure, in the semiconductor module of the first or second aspect, a plate-like conductive member (15) is provided on a surface of the substrate (10) opposite to the mounting surface (11), and the reference end face (43) and a surface of the conductive member (15) opposite to the substrate (10) are arranged on the same plane.

[0011] In the third aspect, when the case (30) is screwed and fixed to, for example, the heat sink (20), it is possible to suppress the application of stress to the substrate (10).

[0012] In a fourth aspect of the present disclosure, in any one of the semiconductor modules of the first to third aspects, the distance h from the position closest to the opposing portion (31) in the component (14) mounted on the substrate (10) to the mounting surface (11) of the substrate (10), the distance H from the reference end face (43) to the opposing portion (31), the distance D1 from the reference end face (43) to the first stepped surface (41), and the distance D2 from the reference end face (43) to the second stepped surface (42) satisfy the conditions D1 < H - h and D2 < H - h.

[0013] In the fourth aspect, it is possible to suppress the interference of the component (14) with the opposing portion (31) of the case (30) even when the mounting surface (11) side of the substrate (10) abuts against either the first stepped surface (41) or the second stepped surface (42).

[0014] In a fifth aspect of the present disclosure, in any one of the semiconductor modules of the first to fourth aspects, the first stepped surface (41) and the second stepped surface (42) extend along the circumferential direction of the peripheral wall portion (32).

[0015] In the fifth aspect, the peripheral edge portion of the substrate (10) can be pressed by the first stepped surface (41) or the second stepped surface (42) to suppress the inclination of the substrate (10).

Brief Description of the Drawings

[0016] [Figure 1]FIG. 1 is a side cross-sectional view showing the configuration of a semiconductor module according to this embodiment. [Figure 2] FIG. 2 is a side cross-sectional view showing a state in which a substrate is in contact with the first step surface. [Figure 3] FIG. 3 is a side cross-sectional view showing a state in which the substrate is brought into contact with a second step surface provided on the outer side of the substrate than the first step surface. [Figure 4] FIG. 4 is a side cross-sectional view showing a state in which the substrate is brought into contact with a second step surface provided inside the substrate relative to the first step surface. DETAILED DESCRIPTION OF THE INVENTION

[0017] Overall structure As shown in FIG. 1, the semiconductor module (1) includes a substrate (10), a semiconductor chip (13), a conductive member (15), and a case (30).

[0018] The substrate 10 is made of an insulating material such as ceramics or aluminum nitride. A metal pattern 12 is formed on a mounting surface 11 of the substrate 10. A semiconductor chip 13 is mounted on the metal pattern 12.

[0019] The semiconductor chip (13) is, for example, an insulated gate bipolar transistor (IGBT) or a diode. In the example shown in Fig. 1, two semiconductor chips (13) are provided. The semiconductor chips (13) are connected to each other by connection wiring (14). The semiconductor chips (13) and the metal pattern (12) are connected by connection wiring (14).

[0020] One end of an external pin 16 is electrically connected to the metal pattern 12. The other end of the external pin 16 extends to protrude outside the case 30. The other end of the external pin 16 is connected to a control board (not shown).

[0021] The conductive member 15 is provided on the surface of the substrate 10 opposite the mounting surface 11. The conductive member 15 is formed in a plate shape. The conductive member 15 is a metal layer made of, for example, copper or aluminum. The conductive member 15 is in thermal contact with the heat sink 20 via grease 21.

[0022] The heat sink 20 is made of a heat-conductive material such as copper, aluminum, etc. The heat sink 20 and a flange portion 33 (described later) of the case 30 are fastened together with fastening screws 50.

[0023] <case> The case 30 is made of, for example, an insulating resin material. The case 30 covers the mounting surface 11 of the substrate 10 to define an internal space 35. The internal space 35 of the case 30 is sealed with a sealing material 36. The sealing material 36 covers the metal pattern 12, the semiconductor chip 13, and the connecting wiring 14.

[0024] The case (30) has a facing portion (31), a peripheral wall portion (32), and a flange portion (33). The facing portion (31) faces the mounting surface (11) of the board (10). The peripheral wall portion (32) extends toward the board (10) along the peripheral edge of the facing portion (31). The flange portion (33) protrudes outward along the peripheral edge of the peripheral wall portion (32) on the side opposite the facing portion (31).

[0025] A plurality of stepped surfaces formed in a staircase pattern are provided on the inner surface of the peripheral wall portion (32). In the example shown in Fig. 2, three stepped surfaces are provided. Of the three stepped surfaces, the second stepped surface counting from the outside of the case (30) is in contact with the mounting surface (11) of the substrate (10). Hereinafter, in Fig. 2, the stepped surface that is in contact with the mounting surface (11) of the substrate (10) is referred to as a first stepped surface (41). The remaining stepped surface is referred to as a second stepped surface (42).

[0026] 2, the second step surface (42) is provided both on the outer side and the inner side of the substrate (10) relative to the first step surface (41). The second step surface (42) extends parallel to the first step surface (41).

[0027] The second step surface (42), which is provided on the outer side of the substrate (10) than the first step surface (41), has a distance from a reference end surface (43) on the peripheral wall portion (32) opposite the opposing portion (31) to the second step surface (42) that is shorter than the distance from the reference end surface (43) to the first step surface (41).

[0028] On the other hand, the second step surface (42), which is provided inside the substrate (10) more than the first step surface (41), has a longer distance from the reference end surface (43) to the second step surface (42) than the distance from the reference end surface (43) to the first step surface (41).

[0029] The first step surface (41) and the second step surface (42) extend in the circumferential direction of the peripheral wall portion (32). Grooves (45) are provided in the first step surface (41) and the second step surface (42). The grooves (45) extend in the circumferential direction of the peripheral wall portion (32).

[0030] 2, the mounting surface 11 of the substrate 10 abuts against the first step surface 41. Therefore, the groove 45 of the first step surface 41 is filled with adhesive 46 to bond the case 30 and the substrate 10 together.

[0031] The reference end surface 43 of the case 30 and the surface of the conductive member 15 opposite the substrate 10 are arranged on the same plane. In the example shown in FIG. 2, the thickness t1 of the substrate 10 is 700 μm. The thickness t2 of the conductive member 15 is 300 μm. In this case, the distance from the reference end surface 43 to the first step surface 41 may be set to 1000 μm.

[0032] This makes it possible to prevent stress from being applied to the substrate (10) when the flange portion (33) of the case (30) is screwed to the heat sink (20).

[0033] In the example shown in FIG. 1, the connection wiring (14) connecting the two semiconductor chips (13) extends so as to curve upward in a side view. Therefore, the location closest to the opposing portion (31) in the components mounted on the substrate (10) is the apex position of the connection wiring (14) that extends in a curved shape.

[0034] As shown in FIGS. 1 and 2, the distance h from the location closest to the opposing portion (31) in the components mounted on the substrate (10) to the mounting surface (11) of the substrate (10), the distance H from the reference end face (43) to the opposing portion (31), the distance D1 from the reference end face (43) to the first step surface (41), and the distance D2 from the reference end face (43) to the second step surface (42) are set so as to satisfy the conditions D1 < H - h and D2 < H - h.

[0035] In this embodiment, the second step surface (42) provided inside the substrate (10) rather than the first step surface (41) has a distance from the reference end face (43) to the second step surface (42) that is longer than the distance from the reference end face (43) to the first step surface (41). Therefore, with the distance to the inner second step surface (42) being D2, it is set so as to satisfy the above-described conditions.

[0036] Incidentally, the thickness of the substrate (10) is determined by the material physical property values of the insulating material and the size of the substrate (10). Here, the material physical property values are, for example, parameters such as stress resistance such as the linear expansion coefficient, Young's modulus, and hardness, and electric field resistance. Thus, when different insulating materials are used as the substrate (10), the thickness of the substrate (10) will be different for each insulating material.

[0037] Hereinafter, the case of housing the substrate (​​​As shown in Fig. 3, when the total thickness obtained by adding the thickness of the substrate 10 and the thickness of the conductive member 15 is smaller than the total thickness of the substrate 10 and the conductive member 15 shown in Fig. 2, the mounting surface 11 of the substrate 10 is brought into contact with a second step surface 42 that is provided on the outer side of the substrate 10 relative to the first step surface 41. In addition, the case 30 and the substrate 10 are bonded together by filling a groove 45 of the second step surface 42 with an adhesive 46.

[0039] In this case, the total thickness obtained by adding the thickness t1 of the substrate (10) and the thickness t2 of the conductive member (15) is equal to the distance from the reference end face (43) to the second step face (42). In the example shown in FIG. 3, the thickness t1 of the substrate (10) is 300 μm. The thickness t2 of the conductive member (15) is 300 μm. In this case, the distance from the reference end face (43) to the second step face (42) is set to 600 μm.

[0040] As shown in Fig. 4, when the total thickness of the substrate 10 and the conductive member 15 is greater than the total thickness of the substrate 10 and the conductive member 15 shown in Fig. 2, the mounting surface 11 of the substrate 10 is brought into contact with a second step surface 42 that is provided on the substrate 10 more inward than the first step surface 41. In addition, the case 30 and the substrate 10 are bonded together by filling a groove 45 of the second step surface 42 with an adhesive 46.

[0041] In this case, the total thickness obtained by adding the thickness t1 of the substrate (10) and the thickness t2 of the conductive member (15) is equal to the distance from the reference end face (43) to the second step face (42). In the example shown in FIG. 4, the thickness t1 of the substrate (10) is 100 μm. The thickness t2 of the conductive member (15) is 2000 μm. In this case, the distance from the reference end face (43) to the second step face (42) is set to 2100 μm.

[0042] -Effects of the embodiment- According to the features of this embodiment, by producing a case (30) of one specification having a first step surface (41) and a second step surface (42), a semiconductor module can be assembled, for example, for a plurality of substrates (10) having different thicknesses, by abutting the mounting surface (11) of the substrate (10) against either the first step surface (41) or the second step surface (42).

[0043] According to the features of this embodiment, by filling the groove portion (45) with adhesive (46) to bond the case (30) and the substrate (10), it is possible to prevent the adhesive (46) from spilling out from between the mounting surface (11) of the substrate (10) and the first step surface (41) or the second step surface (42).

[0044] According to the feature of this embodiment, when the case (30) is fixed to, for example, the heat sink (20) by screws, it is possible to suppress the application of stress to the substrate (10).

[0045] According to the features of this embodiment, even when the mounting surface (11) of the substrate (10) is abutted against either the first step surface (41) or the second step surface (42), interference of the component (14) with the opposing portion (31) of the case (30) can be prevented.

[0046] According to the feature of this embodiment, the peripheral edge of the substrate (10) is pressed by the first step surface (41) or the second step surface (42), thereby preventing the substrate (10) from tilting.

[0047] Other Embodiments In the above embodiment, a configuration has been described in which groove portions (45) extending along the circumferential direction of the peripheral wall portion (32) are provided on the first step surface (41) and the second step surface (42). However, for example, the groove portions (45) may be absent, or the groove portions (45) may be provided around the entire circumference, or may be provided at multiple locations along the circumferential direction.

[0048] Here, if the grooves 45 are provided around the entire periphery, it is easier to fix the substrate 10. Also, if the grooves 45 are provided in multiple locations, the amount of adhesive 46 used can be reduced.

[0049] In the above embodiment, a configuration has been described in which the first step surface (41) and the second step surface (42) extend along the circumferential direction of the peripheral wall portion (32). However, the first step surface (41) and the second step surface (42) may be provided along the entire circumference, or may be provided at multiple locations along the circumferential direction.

[0050] Here, if the first step surface 41 and the second step surface 42 are provided along the entire periphery, tilt of the substrate 10 can be further reduced. Also, if the first step surface 41 and the second step surface 42 are provided partially at a plurality of locations, tilt of the substrate 10 can be minimized while reducing the amount of material for the peripheral wall 32.

[0051] Although the embodiments and modifications have been described above, it will be understood that various modifications in form and detail are possible without departing from the spirit and scope of the claims. Furthermore, elements of the above embodiments, modifications, and other embodiments may be combined or substituted as appropriate. Furthermore, the terms "first," "second," "third," etc. in the specification and claims are used to distinguish between terms to which these terms are attached, and do not limit the number or order of those terms. [Industrial Applicability]

[0052] As described above, the present disclosure is useful for semiconductor modules. [Explanation of symbols]

[0053] 1. Semiconductor module 10 Substrate 11 Mounting surface 14 Connection wiring (parts) 15 Conductive materials 30 ケース 31 Target Department 32. Perimeter wall 41. First segment difference surface 42. Second segment difference surface 43 Reference end face 45. Ditch

Claims

1. A semiconductor module comprising a substrate (10) and a case (30) that covers a mounting surface (11) of the substrate (10), The case (30) has a facing portion (31) facing the mounting surface (11) of the board (10) and a peripheral wall portion (32) extending toward the board (10) along the periphery of the facing portion (31), a first step surface (41) that abuts against the mounting surface (11) of the substrate (10) and a second step surface (42) that extends parallel to the first step surface (41) at least one of the outer side and the inner side of the substrate (10) relative to the first step surface (41); When the second step surface (42) is provided on the outer side of the substrate (10) than the first step surface (41), the distance from a reference end surface (43) of the peripheral wall portion (32) on the opposite side to the opposing portion (31) to the second step surface (42) is shorter than the distance from the reference end surface (43) to the first step surface (41), When the second step surface (42) is provided closer to the substrate (10) than the first step surface (41), the distance from the reference end surface (43) to the second step surface (42) is longer than the distance from the reference end surface (43) to the first step surface (41), a groove (45) extending in the circumferential direction of the peripheral wall (32) is provided in the first step surface (41) and the second step surface (42); The groove (45) is filled with an adhesive (46) that bonds the case (30) and the substrate (10). Semiconductor module.

2. 2. The semiconductor module of claim 1, A plate-shaped conductive member (15) is provided on the surface of the substrate (10) opposite to the mounting surface (11), The reference end surface (43) and the surface of the conductive member (15) opposite to the substrate (10) are arranged on the same plane. Semiconductor module.

3. 3. The semiconductor module according to claim 1, a distance h from a point of the component (14) mounted on the substrate (10) closest to the opposing portion (31) to the mounting surface (11) of the substrate (10), a distance H from the reference end face (43) to the opposing portion (31), a distance D1 from the reference end face (43) to the first step surface (41), and a distance D2 from the reference end face (43) to the second step surface (42), D1<H-h, D2<H-h Satisfy the condition that Semiconductor module.

4. 3. The semiconductor module according to claim 1, The first step surface (41) and the second step surface (42) extend along the circumferential direction of the peripheral wall portion (32). Semiconductor module.

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