Semiconductor device and method for manufacturing semiconductor device

Abstract

To provide a semiconductor device, for example, which can suppress degradation of a joint part.SOLUTION: The semiconductor device includes: a heat sink; an insulation substrate metal-jointed to the heat sink; a semiconductor element metal-joined to the insulation substrate; and a sealing resin part for covering the insulation substrate, the semiconductor element, and a region around a joint part of the insulation substrate and the semiconductor element and covering a region around a joint part of the heat sink and the insulation substrate.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a semiconductor device and a method for manufacturing the semiconductor device. [Background technology]

[0002] For example, the semiconductor device described in Patent Document 1 includes a semiconductor module having a flat heat spreader, and a heat sink joined to the heat spreader by metal bonding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2023-70910 Summary of the Invention [Problem to be solved by the invention]

[0004] Since metal joints may deteriorate due to oxidation, it is desirable to isolate them from the outside air. An object of the present invention is to provide a semiconductor device etc. capable of suppressing deterioration of the joints. [Means for solving the problem]

[0005] The present invention, which was completed with this objective in mind, is a semiconductor device comprising a heat sink, an insulating substrate metal-bonded to the heat sink, a semiconductor element metal-bonded to the insulating substrate, and a sealing resin part covering at least the insulating substrate, the semiconductor element, a joint between the insulating substrate and the semiconductor element, and the periphery of the joint between the heat sink and the insulating substrate. Here, the heat sink has a flat plate-shaped portion and fins protruding from the flat plate-shaped portion in a direction intersecting the plate surface of the flat plate-shaped portion, the insulating substrate is smaller than the flat plate-shaped portion and is joined to the surface of the flat plate-shaped portion opposite the side on which the fins are provided, and the sealing resin portion may cover the opposite surface of the flat plate-shaped portion. Alternatively, the heat sink may have a flat plate-shaped portion and fins protruding from the flat plate-shaped portion in a direction intersecting the plate surface of the flat plate-shaped portion, the insulating substrate may be joined to the surface of the flat plate-shaped portion opposite the side on which the fins are provided, and the sealing resin portion may cover the periphery of the side of the flat plate-shaped portion. Alternatively, the heat sink may have a flat plate-shaped portion and fins protruding from the flat plate-shaped portion in a direction intersecting the plate surface of the flat plate-shaped portion, a first portion of the flat plate-shaped portion on the side where the fins are provided protruding outward further than a second portion on the opposite side to the fins, the insulating substrate is joined to the second portion of the flat plate-shaped portion, and the sealing resin portion covers the periphery of the first and second portions of the flat plate-shaped portion. From another perspective, the present invention is a method for manufacturing a semiconductor device, comprising: a step of supplying a first metal bonding material onto a first surface of an insulating substrate or onto a heat sink; a step of placing the insulating substrate on the heat sink so that the first metal bonding material is interposed between the heat sink and the insulating substrate; a first pressurizing and heating step of applying pressure and heat to perform bonding using the first metal bonding material; a step of supplying a second metal bonding material onto a second surface of the insulating substrate; a step of placing the semiconductor element on the second surface so that the second metal bonding material is located between the second surface and the semiconductor element; a second pressurizing and heating step of applying pressure and heat to perform bonding using the second metal bonding material; an arrangement step of arranging the insulating substrate, the heat sink, and the semiconductor element in a mold; and a filling step of filling the mold with resin. Here, the first pressurizing and heating step may be carried out before the second pressurizing and heating step. Furthermore, a lead frame may be attached to the semiconductor element after the first pressurizing and heating step and the second pressurizing and heating step. Effect of the Invention

[0006] According to the present invention, it is possible to provide a semiconductor device and the like capable of suppressing deterioration of a joint. [Brief description of the drawings]

[0007] [Figure 1] 1 is a diagram showing an example of the appearance of a semiconductor device according to a first embodiment; [Diagram 2] FIG. 2 is an example of an exploded view of components constituting the semiconductor device according to the first embodiment. [Diagram 3] 1 is a diagram showing an example of a cross section of a semiconductor device according to a first embodiment. [Figure 4] FIG. 1 is a diagram used to explain the integration process. [Diagram 5] FIG. 1 is a diagram used to explain the integration process. [Figure 6] FIG. 2 is a diagram showing an example of a schematic configuration of a mold according to the first embodiment. [Figure 7] FIG. 13 is a diagram showing an example of a schematic configuration of a semiconductor device according to a second embodiment. [Figure 8] FIG. 13 is a diagram showing an example of a schematic configuration of a mold according to a second embodiment. [Figure 9] FIG. 13 is a diagram illustrating an example of a schematic configuration of a semiconductor device according to a third embodiment. [Figure 10] FIG. 13 is a diagram showing an example of a schematic configuration of a mold according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. First Embodiment FIG. 1 is a diagram showing an example of the external appearance of a semiconductor device 1 according to the first embodiment. FIG. 2 is an example of an exploded view of components constituting the semiconductor device 1 according to the first embodiment. 3 is a diagram showing an example of a cross section of the semiconductor device 1 according to the first embodiment, taken along line III-III of FIG.

[0009] The semiconductor device 1 according to the first embodiment includes a semiconductor module 100 and a cooling device 2 that cools the semiconductor module 100. As shown in Fig. 1, the semiconductor device 1 is mounted, for example, on an automobile with the cooling device 2 and the semiconductor module 100 joined together. Hereinafter, the direction in which the cooling device 2, a cooler 10 described below, and the semiconductor module 100 are stacked may be referred to as the "stacking direction". In addition, in the rectangular cooler 10, the longitudinal direction of the rectangle perpendicular to the stacking direction may be referred to as the "longitudinal direction", and the lateral direction of the rectangle may be referred to as the "lateral direction". In addition, in the stacking direction, the cooling device 2 side (lower side in Fig. 1) may be referred to as the "first side", and the semiconductor module 100 side (upper side in Fig. 1) may be referred to as the "second side".

[0010] (Cooling device 2) The cooling device 2 includes a cooler 10, which is a cooler capable of circulating a cooling liquid therethrough, a support member 50 that supports the cooler 10, and a connecting member 60 that connects the cooler 10 and the support member 50.

[0011] (Cooler 10) The cooler 10 includes a plurality of heat sinks 20 (three in this embodiment), a case 30 that houses the fins 22 of the heat sink 20 and forms a space through which the cooling liquid flows, and a cover 40 that covers the opening of the case 30. The case 30 and the cover 40 form a housing 15 that surrounds the multiple fins 22 of the heat sink 20 so that the cooling liquid flows between the multiple fins 22.

[0012] As shown in FIG. 3, the heat sink 20 has a flat plate-shaped portion 21 and a plurality of fins 22 protruding from the flat plate-shaped portion 21 in a direction perpendicular to the plate surface. The flat plate portion 21 has a first surface 211 which is the surface on which the fins 22 are formed, and a flat second surface 212 which is the surface on which the fins 22 are not formed. The multiple fins 22 are formed in a partial area toward the center of the first surface 211, and the outside of the area on the first surface 211 where the fins 22 are formed is a flat surface. Hereinafter, the flat surface on the outside of the area where the fins 22 are formed may be referred to as an outer surface 213.

[0013] The fins 22 may be, for example, columnar in shape, with the direction of protrusion from the flat plate portion 21 being the stacking direction. The shape of the fins 22 cut along a plane perpendicular to the protruding direction (hereinafter, may be referred to as the "cross-sectional shape") may be, for example, a quadrangle such as a square, a rectangle, or a diamond. The cross-sectional shape may be, for example, a circle or an ellipse. The fins 22 may be flat. If they are flat, they may be parallel to the longitudinal direction, or may be wavy with portions inclined in the longitudinal direction.

[0014] The heat sink 20 may be formed by forging or cutting. The heat sink 20 may be formed from at least one of copper and aluminum. The aluminum may be A1000 series pure aluminum such as A1100.

[0015] The case 30 is concave and has a flat bottom 31, a side 32 extending from the outer periphery of the bottom 31 in a direction perpendicular to the bottom 31, and a flange 33 protruding outward from the tip of the side 32 in a direction parallel to the bottom 31. The bottom 31 and the side 32 form a recess, and the flange 33 is formed around this recess. The bottom portion 31 has a first circular through hole 34 formed at one end in the longitudinal direction, and a second circular through hole 35 formed at the other end in the longitudinal direction. The material of the case 30 can be, for example, aluminum or copper.

[0016] The cover 40 is flat and has an outer shape that is the same as the outer periphery of the flange 33 of the case 30. When the cover 40 and the flange 33 of the case 30 are joined together, the cover 40 closes the opening of the recess of the case 30. Examples of a method for joining the cover 40 and the case 30 include brazing and laser welding.

[0017] The cover 40 has rectangular third through holes 43 formed between one longitudinal end and the other longitudinal end, the same number as the heat sink 20 (three in this embodiment) for passing the fins 22 of the heat sink 20 through.

[0018] The cover 40 is joined to the outer surface 213 around the fins 22 of the flat portion 21 of the heat sink 20, with the fins 22 of the heat sink 20 passing through the third through holes 43. The method for joining the cover 40 and the heat sink 20 can be, for example, brazing or laser welding. The material of the cover 40 can be, for example, aluminum or copper.

[0019] (Connecting member 60) The connecting member 60 is an elliptical cylindrical member whose short axis direction is the longitudinal direction of the case 30 and whose long axis direction is the short side direction of the case 30. A circular first through hole 61 is formed in the center of the connecting member 60. The first through hole 61 has the same shape as the first through hole 34 and the second through hole 35 of the case 30 of the cooler 10. In addition, the connecting member 60 is formed with second through holes 62 on both outer sides of the first through hole 61 in the long axis direction.

[0020] The material of the connecting member 60 can be, for example, aluminum or copper. The connecting member 60 is joined to the bottom 31 of the case 30. The method of joining the connecting member 60 and the case 30 can be, for example, brazing or laser welding.

[0021] (Support member 50) The support member 50 has a first space 51 recessed from the top surface at one end in the longitudinal direction, and a second space 52 recessed from the top surface at the other end in the longitudinal direction. An opening 51a on the top surface side of the first space 51 and an opening 52a on the top surface side of the second space 52 have the same shape as the first through hole 61 of the connecting member 60. A groove 51b into which an O-ring 55 is fitted is formed around the opening 51a in the support member 50, and a groove 52b into which an O-ring 56 is fitted is formed around the opening 52a. In addition, the support member 50 has female threads 51c formed on both outer sides of the groove 51b in the long axis direction, and female threads 52c formed on both outer sides of the groove 52b in the long axis direction.

[0022] A communication hole is formed in the support member 50, connecting the first space 51 with the outside in a direction perpendicular to the stacking direction (the short side direction in Figs. 1 and 2), and a first joint 53 is fitted into the communication hole. Also, a communication hole is formed in the support member 50, connecting the second space 52 with the outside in a direction perpendicular to the stacking direction, and a second joint 54 is fitted into the communication hole. The material of the support member 50 can be, for example, aluminum or copper.

[0023] (Function of cooling device 2) In the semiconductor device 1 configured as described above, the cooling liquid that has flowed into the first space 51 from the first joint 53 of the support member 50 flows into the inside of the cooler 10 through the opening 51a and the first through hole 34 formed at one end in the longitudinal direction of the case 30 of the cooler 10. The cooling liquid that has flowed into the inside of the cooler 10 advances in the longitudinal direction through between the fins 22 of the heat sink 20 and between the fin 22 and the side part 32 of the case 30, and flows out of the cooler 10 through the second through hole 35 formed at the other end in the longitudinal direction of the case 30. The cooling liquid that has flowed out of the cooler 10 enters the second space 52 through the opening 52a formed in the support member 50 and flows out from the second joint 54. In this manner, while the cooling liquid flows through the inside of the cooler 10, the semiconductor module 100 joined to the cooler 10 is cooled.

[0024] (Semiconductor module 100) As shown in FIG. 3, the semiconductor module 100 includes an insulating substrate 110, a semiconductor element 120, and a lead frame . The insulating substrate 110 is an insulating heat dissipation circuit board in which copper plates are bonded and integrated to both sides of a ceramic plate 111, which is an insulating material, and has a first copper plate 112 provided on a first side of the ceramic plate 111 and a second copper plate 113 provided on a second side of the ceramic plate 111. Bonding between the ceramic plate 111 and the first and second copper plates 112 and 113 can be performed, for example, by using a direct copper bonding method or an active metal brazing method.

[0025] When viewed in the stacking direction, the ceramic plate 111 is larger than the first copper plate 112 and the second copper plate 113. Furthermore, when viewed in the stacking direction, the ceramic plate 111 is smaller than the flat portion 21 of the heat sink 20. The semiconductor element 120 can be, for example, a power semiconductor element for controlling and supplying power such as an inverter.

[0026] The semiconductor module 100 also has a first bonding portion 141 that bonds the insulating substrate 110 and the heat sink 20, a second bonding portion 142 that bonds the insulating substrate 110 and the semiconductor element 120, and a third bonding portion 143 that bonds the semiconductor element 120 and the lead frame 130. The first bonding portion 141, the second bonding portion 142, and the third bonding portion 143 can be, for example, solder or a sintered metal (e.g., silver or copper).

[0027] The semiconductor module 100 also has a sealing resin part 150 that covers at least the insulating substrate 110, the semiconductor element 120, the first bonding part 141, the second bonding part 142, and the third bonding part 143. The sealing resin part 150 is molded using a thermosetting resin having a curing temperature of, for example, 200° C. or higher. Examples of the thermosetting resin include resins having insulating properties such as epoxy resins and silicone resins.

[0028] The sealing resin portion 150 covers one end of the lead frame 130, that is, the end on the third bonding portion 143 side, and exposes the other end, that is, the tip portion. Moreover, the sealing resin portion 150 according to this embodiment also covers the second surface 212 of the flat plate portion 21 of the heat sink 20 in order to cover the periphery of the first joint portion 141 .

[0029] (Method of Manufacturing Semiconductor Device 1) An example of a method for manufacturing the semiconductor device 1 will now be described. The manufacturing method of the semiconductor device 1 includes a step of integrating the semiconductor module 100 and the heat sink 20 (hereinafter, may be referred to as an "integration step"). Hereinafter, the semiconductor module 100 and the heat sink 20 integrated together may be referred to as a "semiconductor unit 170". The manufacturing method of the semiconductor device 1 also includes a step of joining the cover 40 to the heat sink 20 joined to the semiconductor module 100. The manufacturing method of the semiconductor device 1 also includes a step of joining the cover 40 to the case 30 and a step of joining the case 30 to the connecting member 60. The manufacturing method of the semiconductor device 1 also includes a step of fastening the male screw of a fastening member such as a bolt passed through the second through hole 62 formed in the connecting member 60 to the female screw 51c of the supporting member 50, thereby attaching the semiconductor module 100, the heat sink 20, the case 30, the cover 40, and the connecting member 60 to the supporting member 50.

[0030] The integration process (in other words, the process of manufacturing the semiconductor unit 170) will be described in detail below. 4 and 5 are diagrams used to explain the integration process. FIG. 6 is a diagram showing an example of a schematic configuration of a mold 500 according to the first embodiment. The integration step includes a first supplying step of supplying a first metal bonding material onto a first surface 112a, which is the surface of the first copper plate 112 of the insulating substrate 110 opposite to the ceramic plate 111, or onto a second surface 212 of the flat portion 21 of the heat sink 20. The first supplying step can be exemplified as a step of applying copper paste, which is an example of the first metal bonding material, onto the first surface 112a or the second surface 212. Fig. 4(a) shows an example of applying copper paste onto the second surface 212.

[0031] The integration step includes a first lamination step of laminating the heat sink 20 and the insulating substrate 110 so that the first metal bonding material is interposed between the heat sink 20 and the insulating substrate 110, as shown in FIG. 4(b). For example, when the copper paste is applied to the first surface 112a of the first copper plate 112 of the insulating substrate 110 in the first supply step, the insulating substrate 110 is placed on the heat sink 20 so that the second surface 212 of the flat plate portion 21 of the heat sink 20 and the first surface 112a of the first copper plate 112 of the insulating substrate 110 face each other in the first lamination step. Similarly, when the copper paste is applied to the second surface 212 of the heat sink 20 in the first supply step, the insulating substrate 110 is placed on the heat sink 20 so that the second surface 212 of the heat sink 20 and the first surface 112a of the insulating substrate 110 face each other in the first lamination step.

[0032] The integration step includes a first pressurizing and heating step in which pressure and heat are applied to bond the heat sink 20 and the insulating substrate 110 by the first metal bonding material. In the first pressurizing and heating step, the heat sink 20 and the insulating substrate 110 laminated in the first lamination step are pressed from the second copper plate 113 side of the insulating substrate 110, and the heat sink 20 and the insulating substrate 110 are heated. The first pressurizing and heating step is, for example, a process in which the heat sink 20 and the insulating substrate 110 laminated in the first lamination step are placed in a known pressurizing device and pressurized while being heated. As a result, the first metal bonding material between the heat sink 20 and the insulating substrate 110 is sintered, and the first bonding portion 141 is formed between the heat sink 20 and the insulating substrate 110. Then, the heat sink 20 and the insulating substrate 110 are bonded and integrated.

[0033] The integration step also includes a second supplying step of supplying a second metal bonding material onto a second surface 113a of the second copper plate 113 of the insulating substrate 110, the second surface 113a being the surface opposite to the ceramic plate 111, as shown in Fig. 4(c). The second supplying step can be exemplified as a step of applying copper paste, as an example of the second metal bonding material, onto the second surface 113a.

[0034] 4(d), the integration step includes a second lamination step of placing the semiconductor element 120 on the second surface 113a of the insulating substrate 110 such that the second metal bonding material is located between the second surface 113a and the semiconductor element 120. In the second lamination step, the semiconductor element 120 is placed on copper paste applied to the second surface 113a of the second copper plate 113 of the insulating substrate 110, for example.

[0035] The integration step also includes a second pressurizing and heating step in which pressure and heat are applied to bond the insulating substrate 110 and the semiconductor element 120 stacked in the second stacking step. In the second pressurizing and heating step, the insulating substrate 110 and the semiconductor element 120 stacked in the second stacking step are pressed from the semiconductor element 120 side, and the insulating substrate 110 and the semiconductor element 120 are heated. In the second pressurizing and heating step, the insulating substrate 110 and the semiconductor element 120 stacked in the second stacking step are placed in a known pressurizing device and pressurized while being heated. As a result, the second metal bonding material between the insulating substrate 110 and the semiconductor element 120 is sintered, and the second bonding portion 142 is formed between the insulating substrate 110 and the semiconductor element 120. As a result, the insulating substrate 110 and the semiconductor element 120 are bonded and integrated.

[0036] 5(a), the integration step includes an attachment step of attaching the lead frame 130 to the semiconductor element 120. The attachment step can be exemplified by attaching the lead frame 130 to the semiconductor element 120 by soldering, for example. As a result, a third joint portion 143 is formed between the semiconductor element 120 and the lead frame 130 by the attachment step, and the semiconductor element 120 and the lead frame 130 are integrated.

[0037] The integration process includes an arrangement process (see FIG. 5(b)) of arranging the insulating substrate 110, heat sink 20, semiconductor element 120, and lead frame 130, which have been integrated in the previous processes, in a mold 500 (one example of a mold), and a filling process (see FIG. 5(c)) of filling the mold 500 with resin. The resin can be, for example, a thermosetting resin such as an epoxy resin or a silicone resin. For example, in the case of silicone resin, it may be filled in a liquid state in the mold 500.

[0038] The integration step also includes a curing step of heating and hardening the resin filled in the mold 500. In the curing step, for example, after the resin is filled in the mold 500, the temperature of the mold 500 can be heated to about 150° C. This causes the resin filled in the mold 500 to harden, and the sealing resin part 150 that covers at least the periphery of the insulating substrate 110, the semiconductor element 120, the first bonding part 141, the second bonding part 142, and the third bonding part 143 is formed. In this manner, the semiconductor unit 170 is manufactured.

[0039] Next, the mold 500 will be described in detail. The mold 500 includes a first mold 510 arranged on a first side in the stacking direction, and a second mold 520 arranged on a second side of the first mold 510. The first mold 510 has a recess 512 recessed toward the first side from a first mating surface 511, which is a mating surface with the second mold 520, into which the heat sink 20 is fitted. The first mold 510 is formed so that the first mating surface 511 is flush with the second surface 212 of the flat plate portion 21 of the heat sink 20. In addition, an opening 513 of the recess 512 is formed so as to have the same shape as the second surface 212 of the flat plate portion 21 of the heat sink 20.

[0040] The second mold 520 is recessed from a second mating surface 521, which is a mating surface with the first mating surface 511 of the first mold 510, to the second side, and has a housing portion 522 for housing the semiconductor module 100. The housing portion 522 is rectangular parallelepiped-shaped and is larger than the shapes of the insulating substrate 110, the semiconductor element 120, the lead frame 130 (excluding the tip portion), the first bonding portion 141, the second bonding portion 142, and the third bonding portion 143 of the semiconductor module 100. In addition, an opening 523 of the housing portion 522 is formed to be larger than an opening 513 of the recess 512 of the first mold 510.

[0041] In the above-mentioned arrangement step, with the heat sink 20 fitted in the recess 512 of the first mold 510, the first mating surface 511 of the first mold 510 and the second mating surface 521 of the second mold 520 are mated. As a result, the semiconductor module 100 is accommodated in the accommodation portion 522 of the second mold 520. Then, resin is filled around the semiconductor module 100 in the accommodation portion 522 of the second mold 520. Furthermore, the resin filled in the accommodation portion 522 is heated and hardened to form the sealing resin portion 150.

[0042] By molding the sealing resin portion 150 using the mold 500 configured as described above, the sealing resin portion 150 covers the peripheries of the first bonding portion 141, the second bonding portion 142, and the third bonding portion 143 so that the first bonding portion 141, the second bonding portion 142, and the third bonding portion 143 are not exposed to the outside. In addition, the sealing resin portion 150 covers the second surface 212 of the flat plate portion 21. The second mold 520 may be composed of a plurality of molds separated in the stacking direction.

[0043] As described above, the semiconductor device 1 comprises a heat sink 20, an insulating substrate 110 metal-bonded to the heat sink 20, a semiconductor element 120 metal-bonded to the insulating substrate 110, and a sealing resin portion 150 that covers at least the insulating substrate 110, the semiconductor element 120, a second bonding portion 142 as an example of a bonding portion between the insulating substrate 110 and the semiconductor element 120, and a first bonding portion 141 as an example of a bonding portion between the heat sink 20 and the insulating substrate 110.

[0044] In the semiconductor device 1 configured as described above, the first bonding portion 141 and the second bonding portion 142 are covered with the sealing resin portion 150, which prevents the first bonding portion 141 and the second bonding portion 142 from deteriorating due to oxidation. Furthermore, since the thickness of the sealing resin portion 150 (in other words, the size in the stacking direction) can be prevented from becoming too thin, it is possible to prevent the sealing resin portion 150 from cracking from the outer periphery of the insulating substrate 110 even if the temperature of the semiconductor module 100 is repeatedly increased to high temperatures.

[0045] In the semiconductor device 1, the heat sink 20 has a flat plate-shaped portion 21 and fins 22 protruding from the flat plate-shaped portion 21 in a direction intersecting the plate surface of the flat plate-shaped portion 21, and the insulating substrate 110 is smaller than the flat plate-shaped portion 21 and is joined to a second surface 212, which is an example of a surface of the flat plate-shaped portion 21 opposite to the side on which the fins 22 are provided. The sealing resin portion 150 covers the second surface 212 of the flat plate-shaped portion 21. According to the semiconductor device 1, the periphery of the first joint portion 141 between the heat sink 20 and the insulating substrate 110 can be covered with high accuracy so that the first joint portion 141 is not exposed to the outside. According to the semiconductor device 1, the thickness of the sealing resin portion 150 can be increased.

[0046] The manufacturing method of the semiconductor device 1 described above includes a step of supplying a first metal bonding material (e.g., copper paste) onto the first surface 112a of the insulating substrate 110 or onto the heat sink 20 (e.g., a first supplying step), and a step of placing the insulating substrate 110 on the heat sink 20 so that the first metal bonding material is interposed between the heat sink 20 and the insulating substrate 110 (e.g., a first stacking step). The manufacturing method of the semiconductor device 1 includes a first pressurizing and heating step of applying pressure and heat to perform bonding using the first metal bonding material, a step of supplying a second metal bonding material (e.g., copper paste) onto the second surface 113a of the insulating substrate 110 (e.g., a second supplying step), and a step of placing the semiconductor element 120 on the second surface 113a so that the second metal bonding material is located between the second surface 113a and the semiconductor element 120 (e.g., a second stacking step). In addition, the manufacturing method of the semiconductor device 1 includes a second pressurizing and heating process in which pressure and heat are applied to perform bonding using a second metal bonding material, a placement process in which the insulating substrate 110, the heat sink 20, and the semiconductor element 120 are placed in a mold 500 (an example of a mold), and a filling process in which resin is filled in the mold 500.

[0047] According to the manufacturing method of the semiconductor device 1, the first bonding portion 141, which is a bonding portion formed by the first metal bonding material, and the second bonding portion 142, which is a bonding portion formed by the second metal bonding material, can be covered with the sealing resin portion 150 filled and molded in the filling step, so that the first bonding portion 141 and the second bonding portion 142 can be prevented from deteriorating due to oxidation. In addition, since it is possible to mold the sealing resin portion 150 by filling the mold 500 with resin after the first pressurizing and heating step and the second pressurizing and heating step, it is possible to use a sealing resin portion 150 having a lower heat resistance than when the sealing resin portion 150 is molded and then heated. In addition, since the temperature during the first pressurizing and heating step and the second pressurizing and heating step can be increased, the bonding reliability of the first bonding portion 141 and the second bonding portion 142 can be improved. In addition, according to the manufacturing method of the semiconductor device 1, the load for pressurization during the first pressurizing and heating step and the second pressurizing and heating step can be increased compared to when the sealing resin portion 150 is molded and then pressurized, so that the bonding reliability of the first bonding portion 141 and the second bonding portion 142 can be improved.

[0048] Furthermore, if the insulating substrate 110 and the heat sink 20 are to be joined after the insulating substrate 110, the semiconductor element 120, the second joint portion 142, etc. have been sealed with resin, it would be necessary to cut the joint surface of the insulating substrate 110 with the heat sink 20. However, according to the manufacturing method of the semiconductor device 1, cutting is not necessary, and therefore the semiconductor device can be manufactured at low cost.

[0049] In the above-described manufacturing method of the semiconductor device 1, it is preferable to perform the first pressurizing and heating step before the second pressurizing and heating step. Since the insulating substrate 110 and the heat sink 20 are bonded first, it is possible to perform a bonding inspection of the interface between the heat sink 20 and the insulating substrate 110 with high accuracy. However, the second pressurizing and heating step may be performed before the first pressurizing and heating step.

[0050] Also, it is preferable to perform an attachment step of attaching the lead frame 130 to the semiconductor element 120 before the arrangement step in the manufacturing method of the semiconductor device 1 described above, in other words, after the first pressurizing and heating step and the second pressurizing and heating step. In the attachment step, when the lead frame 130 is attached to the semiconductor element 120 by solder, for example, performing the first pressurizing and heating step or the second pressurizing and heating step after the attachment step may cause the solder to re-melt, but performing the attachment step later can prevent the solder from re-melting.

[0051] <Second embodiment> FIG. 7 is a diagram showing an example of a schematic configuration of a semiconductor device 201 according to the second embodiment. The semiconductor device 201 according to the second embodiment differs from the semiconductor device 1 according to the first embodiment in that it has a semiconductor unit 270 corresponding to the semiconductor unit 170. The semiconductor unit 270 differs from the semiconductor unit 170 in that it has a heat sink 220 corresponding to the heat sink 20 and a sealing resin part 250 corresponding to the sealing resin part 150. The following describes the differences from the first embodiment. The same reference numerals are used for the same parts in the first and second embodiments, and detailed descriptions thereof will be omitted.

[0052] The heat sink 220 has a different size of a flat plate portion 221 corresponding to the flat plate portion 21 from the heat sink 20. When viewed in the stacking direction, the flat plate portion 221 is the same size as the first copper plate 112 of the insulating substrate 110. Therefore, the flat plate portion 221 of the heat sink 220 has a second surface 221b corresponding to the second surface 212 entirely joined to the first copper plate 112 of the insulating substrate 110 via the first joint portion 141. The sealing resin portion 250 differs from the sealing resin portion 150 in that it covers the periphery of the side surface 225 of the flat plate portion 221 of the heat sink 220 .

[0053] FIG. 8 is a diagram showing an example of a schematic configuration of a mold 600 according to the second embodiment. The mold 600 of the second embodiment differs from the mold 500 of the first embodiment in that the mating position between the first mating surface 611 of the first mold 610 corresponding to the first mold 510 and the second mating surface 621 of the second mold 620 corresponding to the second mold 520 is the center in the stacking direction of the side 225 of the heat sink 220.

[0054] More specifically, an opening 613 of a recess 612 corresponding to the recess 512 of the first mold 610 is formed to have the same shape as the flat plate portion 221 of the heat sink 220 when viewed in the stacking direction, and its position in the stacking direction is the center of the side surface 225 of the heat sink 220. Therefore, the recess 612 causes a second side portion of the flat plate portion 221 of the heat sink 220 to protrude from the first mating surface 611.

[0055] The shape of the opening 623 of the accommodation portion 622 corresponding to the accommodation portion 522 of the second mold 620 when viewed in the stacking direction is the same as the shape of the accommodation portion 522 of the second mold 520, but the position of the opening 623 in the stacking direction is the center of the side surface 225 of the heat sink 220. Therefore, the accommodation portion 622 also accommodates a portion of the second side of the flat portion 221 of the heat sink 220.

[0056] In the semiconductor device 201 configured as described above, the heat sink 220 has a flat plate-shaped portion 221 and fins 22 protruding from the flat plate-shaped portion 221 in a direction intersecting the plate surface of the flat plate-shaped portion 221, and the insulating substrate 110 is joined to the second surface 221b of the flat plate-shaped portion 221. The sealing resin portion 250 covers the periphery of the side surface 225 of the flat plate-shaped portion 221. According to the semiconductor device 201, the periphery of the first joint portion 141 between the heat sink 220 and the insulating substrate 110 can be covered with high accuracy so that the first joint portion 141 is not exposed to the outside. Also, according to the semiconductor device 201, the thickness of the sealing resin portion 250 on the first side of the ceramic plate 111 of the insulating substrate 110 can be made thicker than the sealing resin portion 150, so that the sealing resin portion 250 can be prevented from cracking from the outer periphery of the insulating substrate 110.

[0057] <Third embodiment> FIG. 9 is a diagram showing an example of a schematic configuration of a semiconductor device 301 according to the third embodiment. The semiconductor device 301 according to the third embodiment differs from the semiconductor device 201 according to the second embodiment in that it has a semiconductor unit 370 corresponding to the semiconductor unit 270. The semiconductor unit 370 differs from the semiconductor unit 270 in that it has a heat sink 320 corresponding to the heat sink 220 and a sealing resin part 350 corresponding to the sealing resin part 250. The following describes the differences from the second embodiment. The same reference numerals are used for the same parts in the second and third embodiments, and detailed descriptions thereof will be omitted.

[0058] The heat sink 320 differs from the heat sink 220 in that the flat plate portion 321 corresponds to the flat plate portion 221. The flat plate portion 321 differs from the flat plate portion 221 in that the first portion 341 on the side where the fins 22 are provided protrudes outward in the plate surface direction more than the second portion 342 on the opposite side to the fins 22. When viewed in the stacking direction, the second portion 342 is the same size as the flat plate portion 221 and the same size as the first copper plate 112 of the insulating substrate 110. Therefore, the second surface 321b of the second portion 342, which corresponds to the second surface 212, is entirely joined to the first copper plate 112 of the insulating substrate 110 via the first joint portion 141. When viewed in the stacking direction, the first portion 341 is larger than the second portion 342. The sealing resin portion 350 differs from the sealing resin portion 250 in that it covers the periphery of the first portion 341 and the second portion 342 of the heat sink 320 .

[0059] FIG. 10 is a diagram showing an example of a schematic configuration of a mold 700 according to the third embodiment. The mold 700 of the third embodiment differs from the mold 600 of the second embodiment in that the mating position between the first mating surface 711 of the first mold 710 corresponding to the first mold 610 and the second mating surface 721 of the second mold 720 corresponding to the second mold 620 is the same as the position in the stacking direction on the first surface 211 of the flat portion 321 of the heat sink 320.

[0060] More specifically, the recess 712 corresponding to the recess 612 of the first mold 710 is formed to have the same shape as the multiple fins 22 of the heat sink 320 when viewed in the stacking direction. Therefore, the recess 712 causes the flat portion 321 of the heat sink 320 to protrude from the first mating surface 711.

[0061] The shape of an opening 723 of a storage portion 722 corresponding to the storage portion 622 of the second mold 720 when viewed in the stacking direction is the same as the shape of the storage portion 622 of the second mold 620, but the position in the stacking direction at the opening 723 is the same as the position in the stacking direction at the first surface 211 of the flat portion 321 of the heat sink 320. Therefore, the storage portion 722 also stores the flat portion 321 of the heat sink 320.

[0062] In the semiconductor device 301 configured as described above, the heat sink 320 has a flat plate-shaped portion 321 and fins 22 protruding from the flat plate-shaped portion 321 in a direction intersecting the plate surface of the flat plate-shaped portion 321, and the flat plate-shaped portion 321 has a first portion 341 on the side where the fins 22 are provided protruding outward from a second portion 342 on the opposite side to the fins 22. The insulating substrate 110 is joined to the second portion 342 of the flat plate-shaped portion 321, and the sealing resin portion 350 covers the periphery of the first portion 341 and the second portion 342 of the flat plate-shaped portion 321. According to the semiconductor device 301, the periphery of the first joint portion 141 can be covered with high accuracy so that the first joint portion 141 between the heat sink 320 and the insulating substrate 110 is not exposed to the outside. Moreover, according to the semiconductor device 301, the thickness of the sealing resin portion 350 on the first side of the ceramic plate 111 of the insulating substrate 110 can be made thicker than the sealing resin portion 150, so that it is possible to prevent the sealing resin portion 350 from cracking from the outer periphery of the insulating substrate 110. Furthermore, according to the semiconductor device 301, the thickness of the sealing resin portion 350 can be made thicker than the sealing resin portion 250 by the amount of the first portion 341 of the flat plate-shaped portion 321, so that it is possible to prevent the sealing resin portion 350 from cracking from the outer periphery of the insulating substrate 110.

[0063] Furthermore, when molding the semiconductor unit 370 using the mold 700, the flat portion 321 of the heat sink 320 can be pressed against the first mold 710, thereby improving the adhesion between the flat portion 321 and the first mold 710 and enhancing moldability. [Explanation of symbols]

[0064] 1,201,301...semiconductor device, 2...cooling device, 10...cooler, 20,220,320...heat sink, 21,221,321...flat plate portion, 22...fin, 30...case, 40...cover, 15...housing, 50...support member, 60...connecting member, 100...semiconductor module, 110...insulating substrate, 111...ceramic plate, 112...first copper plate, 112a...first surface, 113...second copper plate, 120...semiconductor element, 130...lead frame, 141...first joint portion, 142...second joint portion, 150,250,350...sealing resin portion, 113a,212...second surface, 225...side surface, 341...first portion, 342...second portion, 500,600,700...mold

Claims

1. A heat sink; an insulating substrate metal-bonded to the heat sink; a semiconductor element metal-bonded to the insulating substrate; a sealing resin portion that covers at least the insulating substrate, the semiconductor element, a joint between the insulating substrate and the semiconductor element, and a joint between the heat sink and the insulating substrate; A semiconductor device comprising:

2. The heat sink has a flat plate-shaped portion and fins protruding from the flat plate-shaped portion in a direction intersecting a plate surface of the flat plate-shaped portion, the insulating substrate is smaller than the flat-plate portion and is joined to a surface of the flat-plate portion opposite to a surface on which the fins are provided; The sealing resin portion covers the opposite surface of the flat plate portion. The semiconductor device according to claim 1 .

3. The heat sink has a flat plate-shaped portion and fins protruding from the flat plate-shaped portion in a direction intersecting a plate surface of the flat plate-shaped portion, the insulating substrate is bonded to a surface of the flat plate portion opposite to a surface on which the fins are provided, The sealing resin portion covers the periphery of a side surface of the flat plate portion. The semiconductor device according to claim 1 .

4. The heat sink has a flat plate-shaped portion and fins protruding from the flat plate-shaped portion in a direction intersecting a plate surface of the flat plate-shaped portion, and a first portion of the flat plate-shaped portion on the side where the fins are provided protrudes outward more than a second portion on the opposite side to the fins, the insulating substrate is joined to the second portion of the flat plate portion, the sealing resin portion covers the periphery of the first portion and the second portion of the flat plate-shaped portion, The semiconductor device according to claim 1 .

5. providing a first metal bonding material on a first surface of the insulating substrate or on a heat sink; placing the insulating substrate on the heat sink such that the first metal bonding material is interposed between the heat sink and the insulating substrate; A first pressurizing and heating process of applying pressure and heat to perform bonding using the first metal bonding material; supplying a second metal bonding material onto a second surface of the insulating substrate; placing a semiconductor element on the second surface such that the second metal bonding material is located between the second surface and the semiconductor element; A second pressurizing and heating process of applying pressure and heat to perform bonding using the second metal bonding material; a placement step of placing the insulating substrate, the heat sink, and the semiconductor element in a mold; a filling step of filling the mold with resin; A method for manufacturing a semiconductor device comprising the steps of:

6. The first pressurizing and heating step is carried out before the second pressurizing and heating step. The method for manufacturing a semiconductor device according to claim 5 .

7. After the first pressurizing and heating step and the second pressurizing and heating step, a lead frame is attached to the semiconductor element. The method for manufacturing a semiconductor device according to claim 5 .

Images