Semiconductor device and power conversion device

Abstract

A semiconductor device and a power conversion device having high reliability are obtained. A semiconductor device (100) is provided with a semiconductor element (4), a lead frame (2), and a sealing resin (7). The semiconductor element (4) is mounted on the lead frame (2). The sealing resin (7) seals the semiconductor element (4) and a part of the lead frame (2). The lead frame (2) includes an inner portion (2c) and an external connection terminal portion (2a). The inner portion (2c) is in contact with the sealing resin (7). The external connection terminal part (2a) protrudes outward from the surface of the sealing resin (7). The lead frame (2) includes a deformed portion (2b). The deformation portion (2b) is located at a boundary portion between the inner side portion (2c) and the external connection terminal portion (2a). The deformation part (2b) is configured so as to concentrate stress in order to bend the lead frame (2). The deformation part (2b) intersects with the surface of the sealing resin (7).

Description

Technical Field

[0001] The present disclosure relates to a semiconductor device and a power conversion device. Background Art

[0002] Conventionally, there is known a semiconductor device in which a semiconductor element and a part of a lead frame are sealed with a sealing resin. For example, Japanese Patent Publication No. 2003-31765 discloses a semiconductor device in which a hole for fixing is formed in an external connection terminal portion which is a part of a lead frame extending to the outside of the sealing resin. The semiconductor device disclosed in Japanese Patent Publication No. 2003-31765 fixes the external connection terminal portion and an external terminal block and a conductor such as a bus bar by a bolt inserted into the hole of the external connection terminal portion. Such a semiconductor device is applied to a power conversion device, for example.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2003-31765 Summary of the invention

[0006] In the above-mentioned conventional semiconductor device, when the semiconductor device is configured in such a manner that the hole of the external connection terminal portion overlaps with the terminal block, there is sometimes a gap between the external connection terminal portion and the terminal block. In this case, when the external connection terminal portion and the terminal block are fixed by bolts, the external connection terminal portion is elastically deformed, and as a result, stress is applied to the sealing resin adjacent to the external connection terminal portion. Such stress causes failures such as cracking of the sealing resin and peeling of the sealing resin from the lead frame, thereby reducing the reliability of the semiconductor device.

[0007] The present disclosure has been made to solve the above-mentioned problems, and provides a semiconductor device and a power conversion device having high reliability.

[0008] The semiconductor device according to the present disclosure comprises a semiconductor element, a lead frame and a sealing resin. The semiconductor element is mounted on the lead frame. The sealing resin seals the semiconductor element and a portion of the lead frame. The lead frame includes an inner portion and an external connection terminal portion. The inner portion is in contact with the sealing resin. The external connection terminal portion protrudes outward from the surface of the sealing resin. The lead frame includes a deformation portion. The deformation portion is located at the boundary portion between the inner portion and the external connection terminal portion. The deformation portion is configured to concentrate stress in order to bend the lead frame. The deformation portion intersects with the surface of the sealing resin.

[0009] The power conversion device according to the present disclosure includes a main conversion circuit and a control circuit. The main conversion circuit includes the semiconductor device described above, and the main conversion circuit converts input power and outputs the power. The control circuit outputs a control signal for controlling the main conversion circuit to the main conversion circuit.

[0010] According to the above, a semiconductor device and a power conversion device having high reliability are obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic plan view for explaining the structure of the semiconductor device according to the first embodiment.

[0012] Figure 2 yes Figure 1 Schematic diagram of the cross section at line segment II-II.

[0013] Figure 3 It is used to illustrate Figure 1 A schematic cross-sectional view of the structure of a semiconductor device shown.

[0014] Figure 4 It is used to illustrate Figure 1 Schematic cross-sectional view of the structure of a modified example of the semiconductor device shown.

[0015] Figure 5 It is a schematic cross-sectional view for explaining the structure of the semiconductor device according to the second embodiment.

[0016] Figure 6 yes Figure 5 Schematic diagram of a partial cross section of region VI.

[0017] Figure 7 It is used to illustrate Figure 5 A partial cross-sectional schematic diagram of the structure of the semiconductor device shown.

[0018] Figure 8 It is used to illustrate Figure 5 FIG. 2 is a schematic partial cross-sectional view of the structure of a modified example 1 of the semiconductor device shown.

[0019] Fig. 9 It is used to illustrate Figure 5 FIG. 2 is a schematic partial cross-sectional view of the structure of a second variation of the semiconductor device shown in FIG.

[0020] Fig.10 It is used to illustrate Figure 5 FIG. 2 is a schematic partial plan view of the structure of a third variation of the semiconductor device shown in FIG.

[0021] Fig.11 It is used to illustrate Figure 5 FIG. 2 is a schematic partial plan view of the structure of a modified example 4 of the semiconductor device shown.

[0022] Fig.12 It is a schematic cross-sectional view for explaining the structure of a semiconductor device according to a third embodiment.

[0023] Fig.13It is used to illustrate Fig.12 A partial cross-sectional schematic diagram of the structure of the semiconductor device shown.

[0024] Fig.14 It is used to illustrate Fig.12 Schematic cross-sectional view of the structure of a modified example of the semiconductor device shown.

[0025] Fig.15 It is used to illustrate Fig.14 A partial cross-sectional schematic diagram of the structure of the semiconductor device shown.

[0026] Fig.16 It is a schematic cross-sectional view for explaining the structure of a semiconductor device according to a fourth embodiment.

[0027] Fig.17 This is a block diagram showing the configuration of a power conversion system to which the power conversion device according to the fifth embodiment is applied.

[0028] (Explanation of symbols)

[0029] 1: heat conducting component; 1a: metal foil; 1b: insulating sheet; 2: lead frame; 2a: external connection terminal portion; 2b: deformation portion; 2ba: first surface; 2bb: second surface; 2c: inner portion; 2d: additional deformation portion; 2e: through hole; 3: solder; 4: semiconductor element; 5: fixing portion; 6: wire; 7: sealing resin; 7a: supporting portion; 7b: cutout portion; 8: bus bar; 9: gasket; 10: bolt; 11: grease; 12: cooler; 21, 21a, 21b, 21c, 21d, 21e, 21f: recessed portion; 100, 200, 300, 400, 1202: semiconductor device; 1100: power supply; 1200: power conversion device; 1201: main conversion circuit; 1203: control circuit; 1300: load. DETAILED DESCRIPTION

[0030] Hereinafter, the embodiments of the present disclosure will be described. In addition, unless otherwise mentioned, the same or corresponding parts in the following drawings are given the same reference numerals, and their description will not be repeated.

[0031] Implementation method 1.

[0032] <Structure of semiconductor device>

[0033] like Figures 1 to 3 As shown, the semiconductor device 100 according to the first embodiment mainly includes a semiconductor element 4 , a lead frame 2 , a heat conducting member 1 , a wire 6 , a cooler 12 , a fixing portion 5 , and a sealing resin 7 .

[0034] The semiconductor element 4 is mounted on the lead frame 2. The semiconductor element 4 is mounted on the surface (upper surface) located on the upper side in the z direction of the lead frame 2. The conductive wire 6 as a connecting member is arranged to connect the electrode (not shown) of the semiconductor element 4 and the lead frame 2. The wire 6 is arranged at Figure 2 The heat conducting member 1 is connected to the back surface of the lead frame 2 opposite to the upper surface on which the semiconductor element 4 is mounted. The heat conducting member 1, a part of the lead frame 2, the semiconductor element 4 and the wire 6 are sealed by a sealing resin 7.

[0035] The surface of the heat conducting member 1 is exposed from the sealing resin 7. The cooler 12 is connected to the surface of the heat conducting member 1 via the grease 11. In a plan view viewed from a direction perpendicular to the surface of the lead frame 2 on which the semiconductor element 4 is mounted, the size of the cooler 12 is larger than the size of the sealing resin 7. In the cooler 12, a fixing portion 5 is formed at a position that does not overlap with the sealing resin 7. As described later, the fixing portion 5 is a portion that fixes the external connection terminal portion 2a of the lead frame 2.

[0036] The lead frame 2 includes an inner portion 2c and an external connection terminal portion 2a. The inner portion 2c is a portion buried in the sealing resin 7 and in contact with the sealing resin 7. The external connection terminal portion 2a is a portion connected to the inner portion 2c and protruding outward from the surface of the sealing resin 7. A through hole 2e is formed on the front end side of the external connection terminal portion 2a. The through hole 2e is a hole for inserting a bolt 10 as a fixing member. The external connection terminal portion 2a is arranged so that the through hole 2e overlaps with the fixing portion 5. The fixing portion 5 is formed with a bolt hole for inserting the bolt 10. The bus bar 8 and the gasket 9 are arranged so as to overlap with the through hole 2e of the external connection terminal portion 2a. A through hole for inserting the bolt 10 is formed in the bus bar 8. The bus bar 8 is positioned so that the through hole of the bus bar 8 overlaps with the through hole 2e of the external connection terminal portion 2a. The gasket 9 is also arranged so as to overlap with the through hole 2e. Bolts 10 are inserted into holes of gasket 9, through holes of bus bar 8, and through holes 2e of external connection terminal 2a and fixed to bolt holes of fixing portion 5. In this way, external connection terminal 2a is fixed to fixing portion 5 and connected to bus bar 8.

[0037] like Figure 2 As shown, the lead frame 2 includes a deformed portion 2b. The deformed portion 2b is located at the boundary between the inner portion 2c and the external connection terminal portion 2a. The deformed portion 2b is configured to concentrate stress in order to bend the lead frame 2. Figure 2 As shown, the lead frame 2 is bent at the deformed portion 2 b due to stress when the external connection terminal portion 2 a is fixed to the fixing portion 5 .

[0038] The surface of the support portion 7a in the sealing resin 7 crosses and contacts the deformed portion 2b. Specifically, the deformed portion 2b includes a first surface 2ba and a second surface 2bb. The second surface 2bb is located on the side opposite to the first surface 2ba. The first surface 2ba is a part of the back surface of the lead frame 2 connected to the heat conducting member 1 in the deformed portion 2b. The second surface 2bb is a part of the upper surface of the lead frame 2 to which the semiconductor element 4 is connected. In the deformed portion 2b, the sealing resin 7 contacts the first surface 2ba but does not contact the second surface 2bb. That is, since the cutout portion 7b is formed in the portion of the sealing resin 7 facing the second surface 2bb of the deformed portion 2b, the second surface 2bb is exposed from the sealing resin 7 in the deformed portion 2b. On the other hand, the first surface 2ba of the deformed portion 2b contacts the support portion 7a of the sealing resin 7. At the first surface 2ba of the deformed portion 2b, the surface of the support portion 7a contacts the bending point or the vicinity within 1 mm from the bending point.

[0039] Hereinafter, each component constituting the semiconductor device 100 will be described.

[0040] The heat conducting component 1 includes a metal foil 1a and an insulating sheet 1b. The insulating sheet 1b is formed on the upper surface of the metal foil 1a. That is, the heat conducting component 1 is a laminated body including the metal foil 1a and the insulating sheet 1b. The heat conducting component 1 functions as an insulating layer with high heat dissipation. The insulating sheet 1b insulates the metal foil 1a from the lead frame 2. In addition, the heat generated in the semiconductor element 4 is dissipated to the metal foil 1a via the insulating sheet 1b. That is, the insulating sheet 1b has a function as a heat transfer component.

[0041] As the metal foil 1a, for example, a high thermal conductivity member such as a copper plate, an aluminum plate, a copper foil, or an aluminum foil is used. The material constituting the insulating sheet 1b is not particularly limited, and may be a single inorganic ceramic material, or a resin material in which at least one of particles and fillers are dispersed. The material constituting the particles and fillers may be, for example, an inorganic ceramic material such as aluminum oxide (Al2O3), aluminum nitride (AlN), silicon nitride (Si3N4), silicon dioxide (SiO2), boron nitride (BN), diamond (C), silicon carbide (SiC), or boron oxide (B2O3). The material constituting the particles and fillers may also be a resin material such as silicone resin or acrylic resin. The resin in which at least one of particles and fillers are dispersed has electrical insulation. The resin in which at least one of particles and fillers are dispersed is not particularly limited, and may be mainly composed of epoxy resin, polyimide resin, silicone resin, or acrylic resin.

[0042] like Figure 2As shown, a lead frame 2 having an arbitrary wiring structure (wiring circuit) formed thereon is provided on a heat conducting member 1. The lead frame 2 has a front surface and a back surface. The back surface of the lead frame 2 including the first surface 2ba of the deformed portion 2b is connected to the insulating sheet 1b of the heat conducting member 1. On the surface of the lead frame 2 including the second surface 2bb of the deformed portion 2b, the back electrode (not shown) of the semiconductor element 4 is bonded to the wiring circuit via the solder 3 as a bonding material.

[0043] The portion of the lead frame 2 protruding from the sealing resin 7 is bolted to the bus bar 8 and the fixing portion 5 as the terminal block as the external connection terminal portion 2a. Figure 3 As shown in FIG. 1 , before the external connection terminal portion 2a is fixed to the fixing portion 5, the external connection terminal portion 2a is formed so as to extend linearly from the surface of the sealing resin 7. Figure 2 As shown, when the fixing portion 5 is integrated with the cooler 12, the height of the lower surface of the external connection terminal portion 2a and the upper surface of the fixing portion 5 may deviate due to the dimensional tolerance of the components. For example, consider a case where the lower surface of the external connection terminal portion 2a is located above the upper surface of the fixing portion 5 at a distance. In this state, when the external connection terminal portion 2a is bolted to the fixing portion 5 by the bolt 10, the external connection terminal portion 2a is deformed in a manner that bends toward the upper surface of the fixing portion 5. As a result, as shown in FIG. Figure 2 As shown, the lower surface of the external connection terminal portion 2a is in contact with the upper surface of the fixing portion 5. At this time, since there is a deformed portion 2b where stress is concentrated when the external connection terminal portion 2a is tightened with a bolt, cracking of the resin in the sealing resin 7 and peeling of the interface between the sealing resin 7 and the external connection terminal portion 2a can be suppressed.

[0044] Various semiconductor elements can be applied as the semiconductor element 4. For example, as the semiconductor element 4, a diode used in a converter section that converts input AC power into DC power, a bipolar transistor used in an inverter section that converts DC power into AC power, an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), a GTO (Gate Turn-Off Thyristor), etc. can be used.

[0045] The sealing resin 7 ensures insulation between the sealed semiconductor element 4 and the lead frame 2 and other components, and functions as a housing of the semiconductor device 100. The sealing resin 7 integrally seals the lead frame 2 and the semiconductor element 4. As a molding method of the sealing resin 7, for example, transfer molding, injection molding, compression molding, etc. can be used. In addition, as a material of the sealing resin 7, for example, epoxy resin, phenolic resin, etc. containing a filler can be used.

[0046] Next, a method for manufacturing the semiconductor device 100 according to the present embodiment configured as described above will be described.

[0047] First, a process of preparing components constituting the semiconductor device 100, such as the lead frame 2 and the semiconductor element 4, is performed. In addition, the prepared lead frame 2 has a plurality of parts connected to each other by a mold frame portion located at the periphery. Next, a process of connecting the components is performed. Specifically, the semiconductor element 4 is bonded to the surface of the lead frame 2 via solder 3. Next, a wire 6 is formed to connect the wiring circuit formed on the lead frame 2 and the semiconductor element 4 by wire bonding.

[0048] Next, a step of sealing the lead frame 2 that has been subjected to the above-mentioned steps with a sealing resin 7 is performed (resin sealing step). In the resin sealing step, the heat conducting component 1 and the lead frame 2 that has been subjected to the above-mentioned steps up to the wire bonding are arranged in a mold. Thereafter, a resin that becomes the sealing resin 7 is injected into the interior of the mold. In this step, molding methods such as transfer molding, compression molding, and injection molding can be applied. After molding, a portion of the lead frame 2 is cut off. Specifically, for example, the mold frame portion is cut off from the outer periphery of the lead frame 2 and removed. In this way, a Figure 3 A semiconductor device 100 is shown.

[0049] Next, the formed semiconductor device 100 is assembled to the cooler 12 via the grease 11. Thereafter, the semiconductor device 100 is mounted inside a power conversion device, for example. Figure 2 As shown, the external connection terminal portion 2a is electrically connected (fastened) to the bus bar 8 in the power conversion device. Figure 1 as well as Figure 2 As shown, the connection structure between the external connection terminal 2a and the bus bar 8 is a bolt fastening structure using a gasket 9 and a bolt 10, but it is not limited thereto and other structures may be adopted. For example, the external connection terminal 2a and the bus bar 8 may be connected by ultrasonic bonding or the like.

[0050] For example, when the thickness T1 of the external connection terminal portion 2a is 0.5 mm, the distance between the sealing resin 7 and the bus bar 8 is 3.5 mm or less. In this case, the distance L1 between the sealing resin 7 and the fixing portion 5 is also substantially 3.5 mm or less. In other words, when the external connection terminal portion 2a is fixed to the fixing portion 5, the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is 7 times or less of the thickness T1 of the external connection terminal portion 2a.

[0051] In this state, when the upper surface of the fixing portion 5 is located at a lower side than the lower surface of the external connection terminal portion 2a, a portion where no sealing resin 7 is present, i.e., a cutout portion 7b, is formed on the upper surface of the external connection terminal portion 2a (the surface connected to the second surface 2bb of the deformation portion 2b) in the resin-sealed semiconductor device 100. In the cutout portion 7b, at least a portion of the upper surface of the external connection terminal portion 2a is not covered by the sealing resin 7. The portion of the upper surface of the external connection terminal portion 2a that is not in contact with the sealing resin 7 may extend to a position that is, for example, about 3.5 mm inward of the surface (edge ​​portion) of the supporting portion 7a of the sealing resin 7 that is in contact with the lower surface of the external connection terminal portion 2a. In addition, the portion where no sealing resin 7 is present, i.e., the cutout portion 7b is preferably formed only in an area located on the external connection terminal portion 2a, but the cutout portion 7b may also be formed in a direction intersecting with the extension direction of the external connection terminal portion 2a (e.g., with respect to the extension direction of the external connection terminal portion 2a). Figure 2 In this case, the bottom surface of the cutout portion 7b may be in the same plane as the upper surface of the external connection terminal portion 2a. For example, Figure 2 The side wall of the cutout portion 7b shown may extend over the Figure 2 The sealing resin 7 is formed to cover the entire width of the sealing resin 7 in the direction perpendicular to the paper surface. In addition, when the thickness T1 of the external connection terminal portion 2a is 0.5 mm, the thickness T2 of the support portion 7a of the sealing resin 7 arranged in contact with the lower surface of the external connection terminal portion 2a is preferably 1.25 mm or more. That is, in the direction from the first surface 2ba toward the second surface 2bb, that is, in the thickness direction, the thickness T2 of the support portion 7a of the sealing resin 7 that contacts the first surface 2ba is 2.5 times or more of the thickness T1 of the external connection terminal portion 2a. In addition, the thickness T1 of the external connection terminal portion 2a may also be 0.5 mm or more.

[0052] When the external connection terminal portion 2a is connected (fastened) to the fixing portion 5 and the bus bar 8, as shown in FIG. Figure 2As shown, the external connection terminal portion 2a is bent in the fastening direction (the direction toward the fixing portion 5: -z direction) at the deformation portion 2b. At this time, the end of the support portion 7a (the corner where the surface of the sealing resin 7 and the upper surface of the support portion 7a intersect) contacts the deformation portion 2b from the lower surface side, so the stress is concentrated on the deformation portion 2b. In other words, the deformation portion 2b becomes the starting point of deformation. Therefore, the deformation portion 2b is deformed (bent) preferentially, so that it is possible to suppress the application of excessive stress to the interface between the lead frame 2 and the sealing resin 7 other than the deformation portion 2b. Therefore, it is possible to suppress the occurrence of cracks in the sealing resin 7 and peeling at the connection interface between the sealing resin 7 and the external connection terminal portion 2a.

[0053] In the semiconductor device 100 constructed as described above, the support portion 7a of the sealing resin 7 is formed on one side of the external connection terminal portion 2a, and the contact point between the end of the support portion 7a of the sealing resin 7 and the external connection terminal portion 2a becomes the deformation starting point (deformation portion 2b). Therefore, by concentrating the stress on the deformation portion 2b, the deformation portion 2b is deformed preferentially, and the resin cracking of the sealing resin 7 in other parts and the interface peeling between the sealing resin 7 and the external connection terminal portion 2a can be suppressed. Therefore, it is not necessary to extend the length of the external connection terminal portion 2a, and it is possible to suppress the entry of moisture into the semiconductor device 100 from the above-mentioned resin cracking or interface peeling portion. In addition, it is also possible to suppress the insulation failure caused by the development of the above-mentioned resin cracking and interface peeling. As a result, the reliability of the semiconductor device 100 can be improved and the enlargement can be suppressed.

[0054] <Modification>

[0055] Figure 4 The semiconductor device 100 shown in FIG. Figure 1 as well as Figure 2 The semiconductor device 100 shown in FIG. 1 has a substantially similar structure to that of the semiconductor device 100 shown in FIG. 1 , but the relative positional relationship between the upper surface of the fixing portion 5 and the lower surface of the external connection terminal portion 2a and the shape of the sealing resin 7 are different from those of FIG. Figure 1 as well as Figure 2 The semiconductor device 100 shown is different. Figure 4 In the semiconductor device 100 shown in FIG. 1 , the height of the upper surface of the fixing portion 5 from the surface of the cooler 12 is higher than the height of the lower surface of the external connection terminal portion 2 a from the surface of the cooler 12 . Figure 4 In the embodiment, by fixing the external connection terminal portion 2a to the fixing portion 5, the external connection terminal portion 2a is bent toward the side away from the cooler 12 (the upper surface side of the lead frame 2 on which the semiconductor element 4 is mounted).

[0056] exist Figure 4In the embodiment, the first surface 2ba of the deformed portion 2b is included in the upper surface of the lead frame 2, and the second surface 2bb is included in the lower surface of the lead frame 2. In addition, the cutout portion 7b in the sealing resin 7 is formed on the lower surface side of the lead frame 2. The supporting portion 7a of the sealing resin 7 is in contact with the upper surface of the lead frame 2 (the surface on which the semiconductor element 4 is mounted). Figure 4 In the semiconductor device 100 shown in FIG. 1 , the structure near the deformed portion 2 b is similar to that of FIG. Figure 2 The semiconductor device 100 shown is reversed in the vertical direction. In this case, since the cutout portion 7b of the sealing resin 7 is formed on the side opposite to the bending direction of the deformed portion 2b, it is also possible to suppress the sealing resin 7 from being damaged in the area on the side opposite to the deformation direction of the deformed portion 2b (the area on the lower surface of the lead frame 2 where the lead frame 2 is exposed from the cutout portion 7b).

[0057] <Function>

[0058] The semiconductor device 100 according to the present disclosure includes a semiconductor element 4, a lead frame 2, and a sealing resin 7. The semiconductor element 4 is mounted on the lead frame 2. The sealing resin 7 seals the semiconductor element 4 and a portion of the lead frame 2. The lead frame 2 includes an inner portion 2c and an external connection terminal portion 2a. The inner portion 2c is in contact with the sealing resin 7. The external connection terminal portion 2a protrudes outward from the surface of the sealing resin 7. The lead frame 2 includes a deformation portion 2b. The deformation portion 2b is located at the boundary portion between the inner portion 2c and the external connection terminal portion 2a. The deformation portion 2b is configured to concentrate stress in order to bend the lead frame 2. The deformation portion 2b intersects with the surface of the sealing resin 7.

[0059] In this way, when an external force is applied to the external connection terminal portion 2a, the deformed portion 2b is deformed first due to the external force. Therefore, the problem that the external force acts on the contact portion between the inner portion 2c of the lead frame 2 and the sealing resin 7 and the sealing resin 7 at the contact portion is peeled off or damaged can be suppressed. Therefore, the reliability of the semiconductor device 100 can be improved. In addition, since the deformed portion 2b is configured to intersect with the surface of the sealing resin 7, that is, the deformed portion 2b partially overlaps with the surface of the sealing resin 7, the size of the external connection terminal portion 2a can be reduced compared to the case where the deformed portion 2b is formed at a position away from the sealing resin 7 in the external connection terminal portion 2a. Therefore, it can also be applied to small semiconductor devices.

[0060] In the semiconductor device 100 described above, the deformed portion 2b includes a first surface 2ba and a second surface 2bb. The second surface 2bb is located on the opposite side to the first surface 2ba. In the deformed portion 2b, the sealing resin 7 is in contact with the first surface 2ba and is not in contact with the second surface 2bb.

[0061] In this case, the sealing resin 7 is in contact with the first surface 2ba of the deformed portion 2b, and therefore, the supporting portion 7a of the sealing resin 7 is arranged only on one side (the first surface 2ba) of the deformed portion 2b. Therefore, when an external force is applied to the first surface 2ba side in such a manner that the external connection terminal portion 2a is bent, the supporting portion 7a of the sealing resin 7 supports (presses) the deformed portion 2b from the first surface 2ba side. As a result, the lead frame 2 can be easily bent at the deformed portion 2b. In addition, since the sealing resin 7 is not in contact with the second surface 2bb of the deformed portion 2b, when the deformed portion 2b is bent, there will be no problem that the second surface 2bb of the deformed portion 2b applies stress to the sealing resin 7 and the sealing resin 7 is damaged.

[0062] In the semiconductor device 100 , the thickness T2 of the support portion 7a of the sealing resin 7 in contact with the first surface 2ba in the direction from the first surface 2ba toward the second surface 2bb is 2.5 times or more the thickness T1 of the external connection terminal portion 2a .

[0063] In this case, since the support portion 7 a of the sealing resin 7 has a sufficient thickness T2 , the support portion 7 a presses the deformed portion 2 b of the lead frame 2 , and can promote the concentration of stress on the deformed portion 2 b and the deformation.

[0064] In the semiconductor device 100 , when the external connection terminal 2 a is fixed to the fixing portion 5 located outside the sealing resin 7 , the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is 7 times or less the thickness T1 of the external connection terminal 2 a .

[0065] In this way, by applying the above-mentioned structure according to the present disclosure to a semiconductor device 100 in which the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is small, even when there is a deviation in the position of the external connection terminal portion 2a and the fixing portion 5, the peeling of the lead frame 2 and the sealing resin 7 and the damage of the sealing resin 7 can be effectively suppressed.

[0066] In the semiconductor device 100, the thickness T1 of the external connection terminal portion 2a is 0.5 mm or more. In this case, since the external connection terminal portion 2a has a certain degree of rigidity, when stress is applied to the external connection terminal portion 2a, the stress is easily transmitted to the sealing resin 7 in contact with the lead frame 2. However, by adopting the structure according to the present disclosure, the damage of the sealing resin 7 caused by the stress can be effectively suppressed.

[0067] Implementation method 2.

[0068] <Structure of semiconductor device>

[0069] Figures 5 to 7 The semiconductor device 200 shown in FIG. Figure 1 as well as Figure 2 The semiconductor device 100 shown in FIG. 1 has a substantially similar structure, but the shapes of the deformed portion 2 b and the sealing resin 7 are different from those of FIG. Figure 1 as well as Figure 2 The semiconductor device 100 shown is different. Figures 5 to 7 In the semiconductor device 200 shown in FIG. 1 , a recess 21 is formed on the upper surface (the surface on the side on which the semiconductor element 4 is mounted) of the lead frame 2 in a manner that the cross-sectional area in the cross section perpendicular to the extension direction of the external connection terminal portion 2a is locally reduced at the deformed portion 2b. The recess 21 as the deformed portion 2b is formed at a position overlapping the surface of the sealing resin 7 in a manner that the recess 21 intersects with the surface of the sealing resin 7. That is, Figures 5 to 7 In the semiconductor device 200 shown in FIG. Figure 1 as well as Figure 2 The recessed portion 21 is formed in the lead frame 2 in the direction in which the lead frame 2 is bent ( Figure 5 The surface (upper surface) on the opposite side to the lower side where the heat conducting member 1 is located.

[0070] The recessed portion 21 is, for example, a cutout portion after the lead frame 2 is partially cut away. For example, the recessed portion 21 can be formed by knurling. Figure 7 As shown in FIG. 1 , such a recess 21 is formed in advance in the semiconductor device 200 before the lead frame 2 is bent. Figure 5 When connected (fastened) to the fixing portion 5 and the bus bar 8 as shown, the structure becomes as follows: the external connection terminal portion 2a is bent in the fastening direction (the direction toward the fixing portion 5) at the portion where the recess 21 as the deformation portion 2b is formed. At this time, since the recess 21 is formed, the lead frame 2 is easy to bend at the portion where the cross-sectional area of ​​the lead frame 2 is locally reduced (the portion where the recess 21 is formed). Furthermore, since the sealing resin 7 is in contact with a portion of the recess 21, a portion of the recess 21 is fixed by the sealing resin 7. Therefore, the lead frame 2 is more likely to bend at the portion where the recess 21 is formed. The cross-sectional shape of the recess 21 may be any shape, and may be. Figure 6 The V-shape shown may also be a U-shape. The inner peripheral surface of the recess 21 may be a curved surface. The recess 21 may be formed in the entire width direction perpendicular to the extending direction of the lead frame 2, or may be formed in a part of the width direction.

[0071] like Figure 5 As shown, the thickness T1 of the external connection terminal portion 2a is, for example, 1 mm. The distance L1 between the sealing resin 7 and the fixing portion 5 or the distance between the sealing resin 7 and the bus bar 8 is, for example, 7 mm or less.

[0072] The semiconductor device 200 can be manufactured by a manufacturing method that is substantially the same as the manufacturing method of the semiconductor device 100 of the first embodiment. Specifically, a process of preparing components constituting the semiconductor device 200, a process of connecting the components, and a process of sealing with the sealing resin 7 are performed to obtain a semiconductor device having Figure 7 The semiconductor device 200 of the structure shown in FIG. 1 is assembled to the cooler 12. Thereafter, the semiconductor device 200 is mounted inside an electric device such as a power conversion device.

[0073] like Figure 5 As shown, the external connection terminal 2a is electrically connected (fastened) to the bus bar 8 in the power conversion device. Similar to the semiconductor device 100 of the first embodiment, the connection structure between the external connection terminal 2a and the bus bar 8 is a bolt-fastened structure using a washer 9 and a bolt 10.

[0074] Here, when the upper surface of the fixing portion 5 is located below the lower surface of the external connection terminal portion 2a, when the external connection terminal portion 2a is connected (fastened) to the fixing portion 5 and the bus bar 8, as shown in FIG. Figure 5 As shown, the external connection terminal portion 2a is structured to bend in the fastening direction (toward the fixing portion 5) at the deformation portion 2b. At this time, by forming a recessed portion 21 at the deformation portion 2b, the cross-sectional area is locally reduced, and the strength of the deformation portion 2b is locally reduced. In addition, the recessed portion 21 of the deformation portion 2b is partially in contact with the sealing resin 7. That is, the recessed portion 21 is partially (for example, half) embedded in the sealing resin 7. Therefore, the deformation portion 2b can be easily deformed. Therefore, the stress that may cause resin cracking and interface peeling between the sealing resin 7 and the lead frame 2 will not act on the sealing resin 7, and the external connection terminal portion 2a can be fastened to the bus bar 8.

[0075] <Modification>

[0076] like Figures 8 to 11 As shown, the recessed portion 21 formed as the deformed portion 2 b in the lead frame 2 may be formed on a surface other than the upper surface of the lead frame 2 . Figure 8 as well as Fig. 9 It is shown Figures 5 to 7 Schematic diagrams of partial cross-sections of Modification 1 and Modification 2 of the semiconductor device 200 shown. Figures 8 to 11 and Figure 7 correspond. Fig.10 as well as Fig.11 It is shown Figures 5 to 7 The shown diagram is a partial plan view of Modification 3 and Modification 4 of the semiconductor device 200 .

[0077] Fig.10 as well as Fig.11The structure of the deformed portion 2 b in a plan view seen from a direction perpendicular to the upper surface of the lead frame 2 is shown.

[0078] Figure 8 The semiconductor device 200 shown in the first modification has Figures 5 to 7 The semiconductor device 200 shown in FIG. 1 has a substantially similar structure, but the arrangement of the recess 21 in the lead frame 2 is different from that in FIG. Figures 5 to 7 The semiconductor device 200 shown is different. Figure 8 In the semiconductor device 200 shown in FIG. 1 , a recess 21 as a deformed portion 2 b is formed on the lower surface of the lead frame 2 . Also, no recess is formed on the upper surface of the lead frame 2 . Figure 8 In FIG. 1 , the recessed portion 21 is also arranged at a position partially overlapping with the surface of the sealing resin 7 .

[0079] Fig. 9 Modification 2 of the semiconductor device 200 shown in FIG. Figures 5 to 7 The semiconductor device 200 shown in FIG. 1 has a substantially similar structure, but the structure of the recess 21 in the lead frame 2 is different from that in FIG. Figures 5 to 7 The semiconductor device 200 shown is different. Fig. 9 In the semiconductor device 200 shown in FIG. 1 , as the deformed portion 2b, recessed portions 21a and 21b are formed in the lead frame 2. The recessed portion 21a is formed in the upper surface of the lead frame 2. The recessed portion 21b is formed in the lower surface of the lead frame 2. Fig. 9 In FIG. 1 , the recessed portion 21a and the recessed portion 21b are also arranged at positions partially overlapping with the surface of the sealing resin 7. Fig. 9 In the embodiment, the recessed portion 21a and the recessed portion 21b are formed at positions facing each other in the thickness direction of the lead frame 2. However, in a plan view viewed from a direction perpendicular to the upper surface of the lead frame 2, the recessed portion 21a and the recessed portion 21b are staggered so that only a portion overlaps.

[0080] Fig.10 Modification 3 of the semiconductor device 200 shown in FIG. Figures 5 to 7 The semiconductor device 200 shown in FIG. 1 has a substantially similar structure, but the arrangement of the deformed portion 2b in the lead frame 2 is different from that in FIG. Figures 5 to 7 The semiconductor device 200 shown is different. Fig.10 In the semiconductor device 200 shown in the figure, as the deformation portion 2b, the recessed portion 21c and the recessed portion 21d are formed in the lead frame 2. The recessed portion 21c is formed in one of the two side surfaces connecting the upper surface and the lower surface of the lead frame 2. The recessed portion 21d is formed in the other of the two side surfaces of the lead frame 2. Fig.10 In FIG. 2 , the recessed portion 21c and the recessed portion 21d are also arranged at positions partially overlapping with the surface of the sealing resin 7. Fig.10In the embodiment, the recessed portion 21c and the recessed portion 21d are formed at positions facing each other in the width direction which is perpendicular to the thickness direction of the lead frame 2 and the direction in which the external connection terminal portion 2a extends.

[0081] Fig.11 The semiconductor device 200 shown in the fourth modification has Fig.10 The semiconductor device 200 shown in FIG. 1 has a substantially similar structure, but the structure of the deformed portion 2b in the lead frame 2 is different from that in FIG. Fig.10 The semiconductor device 200 shown is different. Fig.11 In the semiconductor device 200 shown, a recess 21c is formed in the lead frame 2 as a deformed portion 2b. The recess 21c is formed in one of the two side surfaces connecting the upper surface and the lower surface of the lead frame 2. No recess is formed in the other of the two side surfaces of the lead frame 2. Fig.11 In FIG. 2 , the recessed portion 21 c is also arranged at a position partially overlapping with the surface of the sealing resin 7 .

[0082] As described above, one or two recesses as the deformed portion 2b may be formed in the lead frame 2, but the number of recesses may be three or more. For example, recesses may be formed on three or four surfaces of the upper surface, the lower surface, one side surface, and the other side surface of the lead frame 2. The recesses 21a to 21d are preferably formed on a group of surfaces facing each other in the lead frame 2.

[0083] <Function>

[0084] In the semiconductor device 200 described above, a recess 21 is formed in the deformed portion 2b so that the cross-sectional area in a cross section perpendicular to the extending direction of the external connection terminal portion 2a is locally reduced. The recess 21 intersects the surface of the sealing resin 7.

[0085] In this case, when an external force is applied to the external connection terminal portion 2a, the lead frame 2 can be easily deformed at the recessed portion 21 as the deformed portion 2b. In addition, since the recessed portion 21 intersects with the surface of the sealing resin 7, the recessed portion 21 is partially fixed by the sealing resin 7. Therefore, since a stress concentration region can be easily formed inside the recessed portion 21, the lead frame 2 can be reliably bent at the recessed portion 21.

[0086] In the semiconductor device 200 , when the external connection terminal 2 a is fixed to the fixing portion 5 located outside the sealing resin 7 , the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is 7 times or less the thickness T1 of the external connection terminal 2 a .

[0087] In this way, by applying the structure of the semiconductor device of embodiment 2 to the semiconductor device 200 in which the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is small, even when there is a deviation in the position of the external connection terminal portion 2a and the fixing portion 5, the lead frame 2 is easy to bend at the recess 21, thereby effectively suppressing the damage of the sealing resin 7.

[0088] In the semiconductor device 200, the thickness T1 of the external connection terminal portion 2a is 0.5 mm or more. In this case, since the external connection terminal portion 2a has a certain degree of rigidity, when stress is applied to the external connection terminal portion 2a, the stress is easily transmitted to the sealing resin 7 in contact with the lead frame 2. However, by adopting the structure according to the present disclosure, the lead frame 2 is easily bent at the recess 21, so that the damage of the sealing resin 7 caused by the stress can be effectively suppressed.

[0089] Implementation method 3.

[0090] <Structure of semiconductor device>

[0091] Fig.12 as well as Fig.13 The semiconductor device 300 shown has Figures 5 to 7 The semiconductor device 200 shown in FIG. 1 has a substantially similar structure to that shown in FIG. 1 , except that an additional deformed portion 2d is formed in the external connection terminal portion 2a of the lead frame 2. Figures 5 to 7 The semiconductor device 200 shown is different. Fig.12 as well as Fig.13 In the semiconductor device 300 shown in the figure, the additional deformation portion 2d is formed at a position farther from the sealing resin 7 than the deformation portion 2b in the external connection terminal portion 2a. The additional deformation portion 2d is a recessed portion 21e formed on the lower surface of the external connection terminal portion 2a. The additional deformation portion 2d is configured to concentrate stress in order to bend the external connection terminal portion 2a by locally reducing the cross-sectional area of ​​the external connection terminal portion 2a.

[0092] like Fig.12 As shown in FIG. 1 , a through hole 2e is formed in the external connection terminal portion 2a for inserting a bolt 10 as a fixing member. The through hole 2e is formed at a position farther from the sealing resin 7 than the additional deformation portion 2d. Figure 5Similarly, in the semiconductor device 200 shown, the bolt 10 as a fixing member is inserted into the hole of the gasket 9, the through hole of the bus bar 8, and the through hole 2e of the external connection terminal portion 2a and fixed to the bolt hole of the fixing portion 5. In a state where the bolt 10 is inserted into the through hole 2e, the recess 21e as the additional deformation portion 2d is arranged at a position overlapping with the outer periphery of the gasket 9. The external connection terminal portion 2a is bent downward (toward the fixing portion 5) at the deformation portion 2b. In addition, the external connection terminal portion 2a is bent in the direction opposite to the deformation direction of the deformation portion 2b (in the direction away from the fixing portion 5) at the additional deformation portion 2d. The portion of the external connection terminal portion 2a located at the front end side of the additional deformation portion 2d (the portion where the through hole 2e is formed) is arranged to extend in the direction along the upper surface of the fixing portion 5.

[0093] The semiconductor device 300 can be manufactured by a manufacturing method that is substantially the same as the manufacturing method of the semiconductor device 200 of the second embodiment. Specifically, a process of preparing components constituting the semiconductor device 300, a process of connecting the components, and a process of sealing with the sealing resin 7 are performed to obtain a semiconductor device having Fig.13 The semiconductor device 300 of the structure shown in FIG. 1 is assembled to the cooler 12. Thereafter, the semiconductor device 300 is mounted inside an electric device such as a power conversion device.

[0094] like Fig.12 As shown, the external connection terminal 2a is electrically connected (fastened) to the bus bar 8 in the power conversion device. Similar to the semiconductor device 100 of the second embodiment, the connection structure between the external connection terminal 2a and the bus bar 8 is a bolt-fastened structure using a washer 9 and a bolt 10.

[0095] Here, when the upper surface of the fixing portion 5 is located below the lower surface of the external connection terminal portion 2a, when the external connection terminal portion 2a is connected (fastened) to the fixing portion 5 and the bus bar 8, as shown in FIG. Fig.12 As shown, the external connection terminal portion 2a is bent in the tightening direction (toward the fixing portion 5) at the deformation portion 2b. Furthermore, the external connection terminal portion 2a is bent in the direction opposite to the bending direction of the deformation portion 2b at the additional deformation portion 2d. At this time, the cross-sectional area is locally reduced by forming a recess 21e at the additional deformation portion 2d, and the strength of the additional deformation portion 2d is locally reduced. Therefore, the additional deformation portion 2d can be easily deformed. Therefore, the stress generated when the external connection terminal portion 2a and the bus bar 8 are connected by the bolt 10 will not act excessively on the sealing resin 7, and the external connection terminal portion 2a can be fastened to the bus bar 8.

[0096] The cross-sectional shape of the recessed portion 21e constituting the additional deformation portion 2d may be any shape, and may be Fig.12The V-shape shown may also be a U-shape. The inner peripheral surface of the recess 21e may be composed of a curved surface. The recess 21e may be formed in the entire width direction orthogonal to the extension direction of the external connection terminal portion 2a, or may be formed in a portion of the width direction. A plurality of recesses 21e may also be formed on the lower surface of the external connection terminal portion 2a. One or two recesses as additional deformation portions 2d may be formed in the external connection terminal portion 2a, but the number of recesses may be more than three. For example, the recess 21e may also be formed on three or four surfaces of the upper surface, the lower surface, one side surface, and the other side surface of the external connection terminal portion 2a. The recess 21e is preferably formed on a group of surfaces facing each other at the external connection terminal portion 2a. The recess 21e is, for example, a cutout portion where the external connection terminal portion 2a is partially removed. For example, the recess 21e may be formed by knurling. The recessed portion 21 b and the recessed portion 21 e are formed on different surfaces of the upper surface and the lower surface of the lead frame 2 , but the recessed portion 21 b and the recessed portion 21 e may be formed on the same surface.

[0097] <Modification>

[0098] Fig.14 as well as Fig.15 The semiconductor device 300 shown has Fig.12 as well as Fig.13 The semiconductor device 300 shown in FIG. 1 has a substantially similar structure to that of the semiconductor device 300 shown in FIG. 1 , but the relative positional relationship between the upper surface of the fixing portion 5 and the lower surface of the external connection terminal portion 2a and the arrangement of the deformed portion 2b and the additional deformed portion 2d are different from those of FIG. Fig.12 as well as Fig.13 The semiconductor device 300 shown is different. In addition, Fig.14 and Fig.12 correspond, Fig.15 and Fig.13 correspond.

[0099] exist Fig.14 as well as Fig.15 In the semiconductor device 300 shown in FIG. 1 , a recess 21b is formed on the lower surface (the surface facing the heat conducting member 1) of the lead frame 2 as the deformed portion 2b. In addition, a recess 21f is formed on the upper surface (the surface on the side where the semiconductor element 4 is located) of the external connection terminal portion 2a as the additional deformed portion 2d. Fig.14 as well as Fig.15 In the semiconductor device 300 shown in FIG. 1 , the arrangement of the deformed portion 2b and the additional deformed portion 2d is similar to that of FIG. Fig.12 as well as Fig.13 The semiconductor device 300 is shown in reverse.

[0100] exist Fig.14 as well as Fig.15In the semiconductor device 300 shown in FIG. 1 , the height of the upper surface of the fixing portion 5 from the surface of the cooler 12 is higher than the height of the lower surface of the external connection terminal portion 2a from the surface of the cooler 12. Fig.14 In the embodiment, the external connection terminal portion 2a is fixed to the fixing portion 5, so that the external connection terminal portion 2a is bent at the deformation portion 2b toward the side away from the cooler 12 (the upper surface side of the lead frame 2 on which the semiconductor element 4 is mounted: +z direction). In addition, the external connection terminal portion 2a is bent in the direction toward the cooler 12 (-z direction) at the additional deformation portion 2d.

[0101] In this way, Fig.14 as well as Fig.15 In the semiconductor device 300 shown in FIG. 1 , the structures of the deformed portion 2b and the additional deformed portion 2d are similar to those of FIG. Fig.12 as well as Fig.13 The semiconductor device 300 shown in FIG. 1 is reversed in the vertical direction. In this case, the same Fig.12 as well as Fig.13 The semiconductor device 300 shown has the same effect.

[0102] <Function>

[0103] In the semiconductor device 300, the external connection terminal 2a includes an additional deformation portion 2d. The additional deformation portion 2d is formed at a position farther from the sealing resin 7 than the deformation portion 2b. The additional deformation portion 2d is configured to concentrate stress in order to bend the external connection terminal 2a.

[0104] In this case, at least two bendable portions (deformation portion 2b and additional deformation portion 2d) are formed in the external connection terminal portion 2a to absorb the stress applied to the external connection terminal portion 2a. Therefore, the stress is easily absorbed due to the bending of the portion, so that the damage of the sealing resin 7 caused by the stress can be suppressed.

[0105] In the semiconductor device 300, a through hole 2e is formed in the external connection terminal portion 2a. The through hole 2e is formed at a position farther from the sealing resin 7 than the additional deformation portion 2d. The through hole 2e is a hole for inserting a fixing member. The fixing member includes a bolt 10 and a gasket 9. The bolt 10 is inserted through the through hole 2e. The gasket 9 is configured to overlap with the through hole 2e. The bolt 10 is inserted through the gasket 9. In the state where the bolt 10 is inserted through the through hole 2e, the additional deformation portion 2d is configured to overlap with the outer periphery of the gasket 9.

[0106] In this case, when the external connection terminal portion 2a is fixed to the fixing portion 5 by the fixing member, the additional deformation portion 2d is arranged near the portion pressed by the gasket 9 of the fixing member. Therefore, due to the stress caused by the fixing member, the external connection terminal portion 2a can be easily bent at the additional deformation portion 2d. Therefore, it is possible to suppress the damage of the sealing resin 7 caused by the stress.

[0107] In the semiconductor device 300 , when the external connection terminal 2 a is fixed to the fixing portion 5 located outside the sealing resin 7 , the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is 7 times or less the thickness T1 of the external connection terminal 2 a .

[0108] In this way, by applying the structure of the semiconductor device of the third embodiment to the semiconductor device 300 in which the distance L1 between the fixed portion 5 and the surface of the sealing resin 7 is small, the external connection terminal portion 2a can be easily bent at the additional deformation portion 2d and the deformation portion 2b even when there is a deviation in the position of the external connection terminal portion 2a and the fixed portion 5. Therefore, the damage of the sealing resin 7 can be effectively suppressed.

[0109] In the semiconductor device 300, the thickness T1 of the external connection terminal portion 2a is greater than or equal to 0.5 mm. In this case, since the external connection terminal portion 2a has a certain degree of rigidity, when stress is applied to the external connection terminal portion 2a, the stress is easily transmitted to the sealing resin 7 in contact with the lead frame 2. However, by adopting the structure according to the present disclosure, the external connection terminal portion 2a is easily bent at the additional deformation portion 2d and the deformation portion 2b, so that the damage of the sealing resin 7 caused by the stress can be effectively suppressed.

[0110] Implementation method 4.

[0111] <Structure of semiconductor device>

[0112] Fig.16 The semiconductor device 400 shown has Figure 1 as well as Figure 2 The semiconductor device 100 shown in FIG. 1 has a substantially similar structure, but the structures of the heat conducting member 1, the cooler 12 and the sealing resin 7 are different from those of FIG. Figure 1 as well as Figure 2 The semiconductor device 100 shown is different. Fig.16 In the semiconductor device 400 shown, the heat conducting member 1 is formed of an insulating sheet 1 b , and the heat conducting member 1 and a part of the cooler 12 are sealed by a sealing resin 7 .

[0113] The insulating sheet 1b constituting the heat conducting member 1 is an insulating layer with high heat dissipation. The insulating sheet 1b electrically insulates the cooler 12 from the lead frame 2. In addition, the insulating sheet 1b as the heat conducting member 1 has the function of dissipating the heat generated in the semiconductor element 4 to the cooler 12 via the insulating sheet 1b. As a material constituting the insulating sheet 1b, the same material as that constituting the lead frame 2 can be used. Figure 1 as well as Figure 2 The material of the insulating sheet 1b in the semiconductor device 100 shown is the same material.

[0114] The sealing resin 7 covers the connection between the lead frame 2 and the heat conducting member 1, and extends to the side of the cooler 12 via the connection between the heat conducting member 1 and the cooler 12. That is, the heat conducting member 1 and a part of the cooler 12 are sealed by the sealing resin 7. Figure 2 Unlike the semiconductor device 100 shown, the metal foil 1 a of the heat-conducting member 1 and the grease 11 are not used, and the heat-conducting member 1 and the cooler 12 are directly connected and fixed by the sealing resin 7 .

[0115] <Function>

[0116] The semiconductor device 400 includes a heat conducting member 1 and a cooler 12. The heat conducting member 1 is connected to a lead frame 2. The cooler 12 is connected to the heat conducting member 1. The heat conducting member 1 and a part of the cooler 12 are sealed by a sealing resin 7.

[0117] In this case, a portion of the cooler 12 connected to the lead frame 2 via the heat conducting member 1 is sealed by the sealing resin 7, so that the grease 11 (see Figure 2 ), etc., can reduce the number of parts of the semiconductor device 400. In addition, by the sealing process using the sealing resin 7, the connection between the heat conducting component 1 and the cooler 12 is also performed. Therefore, compared with the case where the sealing process using the sealing resin 7 and the process of connecting the cooler 12 and the heat conducting component 1 are performed as different processes, the manufacturing process of the semiconductor device can be simplified.

[0118] In the semiconductor device 400 having the above structure, the deformed portion 2d is formed in the lead frame 2 as in the semiconductor device 100 of the first embodiment, so that damage to the sealing resin 7 can be suppressed. As a result, the semiconductor device 400 with improved reliability can be realized.

[0119] In the semiconductor device 400 , when the external connection terminal 2 a is fixed to the fixing portion 5 located outside the sealing resin 7 , the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is 7 times or less the thickness T1 of the external connection terminal 2 a .

[0120] In this way, by applying the structure of the semiconductor device of the fourth embodiment to the semiconductor device 400 in which the distance L1 between the fixing portion 5 and the surface of the sealing resin 7 is small, the lead frame 2 can be easily bent at the deformation portion 2b even when there is a deviation in the position of the external connection terminal portion 2a and the fixing portion 5. Therefore, the damage of the sealing resin 7 can be effectively suppressed.

[0121] In the semiconductor device 400, the thickness T1 of the external connection terminal portion 2a is 0.5 mm or more. In this case, since the external connection terminal portion 2a has a certain degree of rigidity, when stress is applied to the external connection terminal portion 2a, the stress is easily transmitted to the sealing resin 7 in contact with the lead frame 2. However, by adopting the structure according to the present disclosure, the lead frame 2 is easily bent at the deformation portion 2b, so that the damage of the sealing resin 7 caused by the stress can be effectively suppressed.

[0122] Implementation method 5.

[0123] This embodiment is an embodiment in which the semiconductor device of any one of Embodiments 1 to 4 is applied to a power conversion device. The present disclosure is not limited to a specific power conversion device, and the following describes a case in which the present disclosure is applied to a three-phase inverter as Embodiment 5.

[0124] Fig.17 1 is a block diagram showing a configuration of a power conversion system to which the power conversion device according to the present embodiment is applied.

[0125] Fig.17 The power conversion system shown includes a power supply 1100, a power conversion device 1200, and a load 1300. The power supply 1100 is a DC power supply, and supplies DC power to the power conversion device 1200. The power supply 1100 can include various power supplies, for example, it can include a DC system, a solar cell, a storage battery, and it can also include a rectifier circuit connected to an AC system, and an AC / DC converter. In addition, the power supply 1100 can also include a DC / DC converter that converts the DC power output from the DC system into a specified power.

[0126] The power conversion device 1200 is a three-phase inverter connected between the power source 1100 and the load 1300, converts the DC power supplied from the power source 1100 into AC power, and supplies the AC power to the load 1300. Fig.17 As shown, the power conversion device 1200 includes: a main conversion circuit 1201 that converts DC power into AC power and outputs it; and a control circuit 1203 that outputs a control signal for controlling the main conversion circuit 1201 to the main conversion circuit 1201 .

[0127] The load 1300 is a three-phase motor driven by the AC power supplied from the power conversion device 1200. The load 1300 is not limited to a specific use, and is a motor mounted on various electrical devices, for example, used as a motor for hybrid vehicles, electric vehicles, railway vehicles, elevators, or air conditioners.

[0128] The following describes the details of the power conversion device 1200. The main conversion circuit 1201 includes a switching element and a freewheeling diode (not shown), and converts the DC power supplied from the power supply 1100 into AC power by opening and closing the switching element, and supplies it to the load 1300. There are many specific circuit structures of the main conversion circuit 1201, but the main conversion circuit 1201 of this embodiment is a 2-level three-phase full-bridge circuit, which can include 6 switching elements and 6 freewheeling diodes connected in anti-parallel with each switching element. At least one of the switching elements and freewheeling diodes of the main conversion circuit 1201 is a switching element or a freewheeling diode possessed by the semiconductor device 1202 corresponding to any semiconductor device in the above-mentioned embodiments 1 to 4. The 6 switching elements are connected in series for every 2 switching elements to form upper and lower branches, and each upper and lower branch constitutes each phase (U phase, V phase, W phase) of the full-bridge circuit. In addition, the output terminals of each upper and lower branch, that is, the three output terminals of the main conversion circuit 1201, are connected to the load 1300.

[0129] In addition, the main conversion circuit 1201 is provided with a driving circuit (not shown) for driving each switching element, but the driving circuit may be built into the semiconductor device 1202, or may be a structure that includes the driving circuit separately from the semiconductor device 1202. The driving circuit generates a driving signal for driving the switching element of the main conversion circuit 1201, and supplies it to the control electrode of the switching element of the main conversion circuit 1201. Specifically, according to the control signal from the control circuit 1203 described later, a driving signal for turning the switching element into a conducting state and a driving signal for turning the switching element into an off state are output to the control electrode of each switching element. When the switching element is maintained in the conducting state, the driving signal is a voltage signal (conduction signal) above the threshold voltage of the switching element, and when the switching element is maintained in the off state, the driving signal is a voltage signal (off signal) below the threshold voltage of the switching element.

[0130] The control circuit 1203 controls the switch elements of the main conversion circuit 1201 to supply the desired power to the load 1300. Specifically, based on the power to be supplied to the load 1300, the time (on-time) for each switch element of the main conversion circuit 1201 to be in the on state is calculated. For example, the main conversion circuit 1201 can be controlled by PWM control, which is a control that modulates the on-time of the switch element according to the voltage to be output. Moreover, a control instruction (control signal) is output to the drive circuit of the main conversion circuit 1201 in such a manner that an on signal is output to the switch element that should be in the on state and an off signal is output to the switch element that should be in the off state at each time point. The drive circuit outputs an on signal or an off signal as a drive signal to the control electrode of each switch element in accordance with the control signal.

[0131] In the power conversion device of this embodiment, since the semiconductor device of any one of Embodiments 1 to 4 is applied as the semiconductor device 1202 constituting the main conversion circuit 1201, high reliability can be obtained.

[0132] In this embodiment, an example of applying the present disclosure to a 2-level three-phase inverter is described, but the present disclosure is not limited thereto and can be applied to various power conversion devices. In this embodiment, a 2-level power conversion device is used, but a 3-level or multi-level power conversion device can also be used. When power is supplied to a single-phase load, the present disclosure can also be applied to a single-phase inverter. In addition, when power is supplied to a DC load, the present disclosure can also be applied to a DC / DC converter or an AC / DC converter.

[0133] In addition, the application of the power conversion device disclosed in the present invention is not limited to the case where the above-mentioned load is an electric motor. For example, it can also be used as a power supply device for an electric discharge machine, a laser processing machine, an induction heating cooker, or a contactless power supply system. It can also be used as a power conditioner for a solar power generation system, a power storage system, etc.

[0134] It should be considered that the embodiments disclosed this time are illustrative in all aspects and are not restrictive. At least two embodiments disclosed this time may be combined as long as there is no contradiction. The basic scope of the present disclosure is represented by the claims rather than the above description, and is intended to include all changes within the meaning and scope equivalent to the claims.

Claims

1. A semiconductor device comprising: Semiconductor components; a lead frame on which the semiconductor element is mounted; and a sealing resin that seals the semiconductor element and a portion of the lead frame, The lead frame includes an inner portion in contact with the sealing resin and an external connection terminal portion protruding outward from a surface of the sealing resin. The lead frame includes a deformation portion at a boundary portion between the inner portion and the external connection terminal portion, the deformation portion being configured to concentrate stress in order to bend the lead frame. The deformed portion intersects the surface of the sealing resin.

2. The semiconductor device according to claim 1, wherein The deformable portion includes a first surface and a second surface located on a side opposite to the first surface. The sealing resin is in contact with the first surface but not in contact with the second surface at the deformed portion.

3. The semiconductor device according to claim 2, wherein: In the direction from the first surface toward the second surface, that is, in the thickness direction, the thickness of a portion of the sealing resin in contact with the first surface is 2.5 times or more the thickness of the external connection terminal portion.

4. The semiconductor device according to claim 1, wherein A recess is formed at the deformed portion so that the cross-sectional area in a cross section perpendicular to the extending direction of the external connection terminal portion is locally reduced. The recess intersects the surface of the sealing resin.

5. The semiconductor device according to any one of claims 1 to 4, wherein: The external connection terminal portion includes an additional deformation portion at a position farther from the sealing resin than the deformation portion, and the additional deformation portion is configured to concentrate stress in order to bend the external connection terminal portion.

6. The semiconductor device according to claim 5, wherein: A through hole for inserting a fixing member is formed in the external connection terminal portion at a position farther from the sealing resin than the additional deformation portion, The fixing member includes: a bolt inserted into the through hole; and a gasket configured to overlap with the through hole and for the bolt to be inserted into. The additional deformation portion is arranged at a position overlapping with the outer periphery of the gasket in a state where the bolt is inserted into the through hole.

7. The semiconductor device according to any one of claims 1 to 6, wherein: When the external connection terminal portion is fixed to a fixing portion located outside the sealing resin, a distance between the fixing portion and the surface of the sealing resin is 7 times or less of a thickness of the external connection terminal portion.

8. The semiconductor device according to any one of claims 1 to 7, wherein: The thickness of the external connection terminal portion is greater than or equal to 0.5 mm.

9. The semiconductor device according to any one of claims 1 to 8, comprising: a heat conducting component connected to the lead frame; and A cooler connected to the heat conducting component, The heat conductive member and a part of the cooler are sealed by the sealing resin.

10. A power conversion device comprising: A main conversion circuit, comprising the semiconductor device according to claim 1, wherein the main conversion circuit converts input power and outputs the power; and The control circuit outputs a control signal for controlling the main conversion circuit to the main conversion circuit.

Images