Semiconductor device and power conversion device

Abstract

Provided is a semiconductor device for which a miniaturization inhibiting factor of the device size is relaxed. The semiconductor device includes at least one sealing body, a terminal, a cooler, and an insulating member. The at least one sealing body contains a semiconductor element. The terminal is electrically connected to the semiconductor element and protrudes from the at least one sealing body. The cooler is joined to the at least one sealing body. The insulating member is provided around the at least one sealing body and on an upper surface of the cooler. The cooler includes a fastening part for securing the cooler. The insulating member includes a wall-shaped protrusion part provided between the fastening part and the terminal.

Description

Semiconductor device and power conversion device

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

[0002] As described in Patent Document 1, semiconductor devices in which a semiconductor element and its peripheral components are sealed with transfer molding are highly reliable, and technological development in this field is underway. For example, Patent Document 1 discloses a technology for improving the reliability of the metal joint between the semiconductor device and the cooler.

[0003] Japanese Patent Application Laid-Open No. 2019-207897

[0004] In semiconductor devices sealed by transfer molding, there is a region with no insulation between the terminals protruding from the sealing material and the ground potential. To prevent spatial discharge between the terminals and the ground potential, it is necessary to increase the distance between the terminals and the ground potential. Such a configuration hinders the miniaturization of semiconductor devices.

[0005] In order to solve the above-mentioned problems, an object of the present disclosure is to provide a semiconductor device that alleviates factors that hinder miniaturization of the device size.

[0006] The semiconductor device according to the present disclosure includes at least one encapsulant, a terminal, a cooler, and an insulating member. The at least one encapsulant contains a semiconductor element. The terminal is electrically connected to the semiconductor element and protrudes from the at least one encapsulant. The cooler is bonded to the at least one encapsulant. The insulating member is provided around the at least one encapsulant and on the top surface of the cooler. The cooler includes a fastening portion for fixing the cooler. The insulating member includes a wall-like protrusion provided between the fastening portion and the terminal.

[0007] According to the present disclosure, a semiconductor device is provided that alleviates factors that hinder miniaturization of device size.

[0008] The objects, features, aspects, and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings.

[0009] 13 is a front view showing the configuration of a semiconductor device in a first embodiment. FIG. 14 is a front view showing the configuration of a semiconductor device in a first embodiment. FIG. 15 is a plan view showing the configuration of a semiconductor device. FIG. 16 is a cross-sectional view showing the internal configuration of a sealing body. FIG. 17 is a front view showing the configuration of a power conversion device in a first embodiment. FIG. 18 is a view showing the configuration of a semiconductor device in a second embodiment. FIG. 19 is a view showing the configuration of a semiconductor device in a third embodiment. FIG. 20 is a view showing the configuration of a semiconductor device in a third embodiment. FIG. 21 is a view showing the configuration of a semiconductor device in a third embodiment. FIG. 22 is a view showing the configuration of a semiconductor device in a fourth embodiment. FIG. 23 is a view showing the configuration of a semiconductor device in a fifth embodiment. FIG. 24 is a plan view showing the configuration of a semiconductor device in a sixth embodiment. FIG. 25 is a plan view showing the configuration of a power conversion device in a sixth embodiment. FIG. 26 is a plan view showing the configuration of a power conversion device in a state in which the number of external electrodes is not reduced. FIG. 27 is a plan view showing the configuration of a power conversion device in a seventh embodiment. FIG. 28 is a plan view showing the configuration of a power conversion device in a seventh embodiment. FIG. 29 is a plan view showing the configuration of a power conversion device in an eighth embodiment. FIG. 29 is an electric circuit diagram of a semiconductor device in a ninth embodiment. FIG. 20 is a front view showing the configuration of a semiconductor device in a tenth embodiment. FIG. 21 is a bottom view showing the configuration of a semiconductor device. FIG. 22 is a functional block diagram showing the configuration of a power conversion system in an eleventh embodiment.

[0010] First Embodiment FIGS. 1 and 2 are front views showing the configuration of a semiconductor device 101 according to a first embodiment. The semiconductor device 101 is a power module fabricated by transfer molding. The semiconductor device 101 includes a sealing body 10, terminals 20, a cooler 30, and an insulating member 40. The insulating member 40 is not shown in FIG. 2. FIGS. 3 and 4 are plan views showing the configuration of the semiconductor device 101. Note that in FIGS. 1, 2, and FIG. 5, which will be described later, the main terminal 20A shown to the right of the sealing body 10 in FIGS. 3 and 4 is not shown, and for ease of understanding, the main terminal 20A, which is behind the signal terminal 20B when viewed from the front, is depicted as if it were in front of the signal terminal 20B.

[0011] First, the configuration of the sealing body 10 and the terminal 20 will be described. Fig. 5 is a cross-sectional view showing the internal configuration of the sealing body 10. The sealing body 10 includes an insulating layer 11, an upper surface metal pattern 12, a lower surface metal pattern 13, a semiconductor element 14, wires 15, and a sealing material 16.

[0012] The insulating layer 11 is made of, for example, silicon nitride (Si ３ N ４ ), aluminum nitride (AlN) and alumina (Al ２ O ３ ) from the viewpoint of thermal conductivity, silicon nitride (Si ３ N ４ From the viewpoint of bending strength, it is preferable that the electrode be made of silicon nitride (Si ３ N ４ The insulating layer 11 may be, for example, a ceramic substrate.

[0013] The upper surface metal pattern 12 is provided on the upper surface of the insulating layer 11. The upper surface metal pattern 12 is made of, for example, copper. The thickness of the upper surface metal pattern 12 is greater than the thickness of the lower surface metal pattern 13.

[0014] The lower surface metal pattern 13 is provided on the lower surface of the insulating layer 11. The lower surface metal pattern 13 is exposed from the lower surface of the sealing body 10. The lower surface metal pattern 13 is formed of, for example, copper. The planar shape of the lower surface metal pattern 13 may be different from the planar shape of the upper surface metal pattern 12. The areas of the upper surface metal pattern 12 and the lower surface metal pattern 13 are smaller than the area of ​​the insulating layer 11.

[0015] The semiconductor element 14 is bonded to the upper surface metal pattern 12 via a bonding material 17A. The bonding material 17A is a conductive material such as solder or sintered silver. From the viewpoint of heat resistance, the solder preferably contains antimony (Sb), which has a high melting point. The thickness of the solder and sintered silver is preferably about 60 μm to improve the heat dissipation of the semiconductor element 14.

[0016] The semiconductor element 14 may be a power semiconductor element, a control IC (Integrated Circuit) for controlling the power semiconductor element, or the like. Examples of the semiconductor element 14 include an insulated gate bipolar transistor (IGBT), a metal oxide semiconductor field effect transistor (MOSFET), a Schottky barrier diode, and the like. The semiconductor element 14 is preferably formed of a wide bandgap semiconductor such as SiC. For example, the semiconductor element 14 may include a MOSFET formed of SiC, i.e., a Si-MOSFET. SiC-MOSFETs generate less heat than Si MOSFETs. This allows multiple semiconductor elements 14 to be arranged close to each other, contributing to the miniaturization of the semiconductor device 101. Alternatively, the semiconductor element 14 may be a reverse-conducting IGBT (RC-IGBT) in which an IGBT and a freewheeling diode are formed on a single semiconductor substrate. The RC-IGBT integrates the IGBT and the freewheeling diode on a single semiconductor chip, thereby reducing the mounting space in the planar direction.

[0017] The terminals 20 include a main terminal 20A and a signal terminal 20B. The main terminal 20A and the signal terminal 20B are electrically connected to the semiconductor element 14. One end of each of the main terminal 20A and the signal terminal 20B protrudes from the encapsulant 10. The main terminal 20A is bonded to the semiconductor element 14 via a bonding material 17B. The main terminal 20A and the semiconductor element 14 form a direct lead bonding structure. The main terminal 20A may be bonded to the upper surface metal pattern 12. If the semiconductor element 14 is an IGBT, the main terminal 20A is electrically connected to, for example, the emitter and collector of the IGBT. The terminals 20 are sheet metal formed by processing a metal plate into a predetermined shape. The terminals 20 are formed, for example, by stamping. The terminals 20 are formed, for example, of oxygen-free copper. The thickness of the terminals 20 is, for example, 0.64 mm.

[0018] The wire 15 connects the signal terminal 20B and the semiconductor element 14. The wire 15 is made of a conductive material such as metal, and is, for example, an aluminum wire.

[0019] The sealing material 16 seals the insulating layer 11, the upper surface metal pattern 12, the lower surface metal pattern 13, the semiconductor element 14, the wires 15, the bonding materials 17A and 17B, and a portion of the terminal 20. However, the lower surface of the lower surface metal pattern 13 is exposed from the sealing material 16. Each component is sealed by transfer molding. The sealing material 16 is, for example, an epoxy resin. In the manufacturing process, the sealing material 16 is preferably formed from a resin with a high glass transition temperature so that thermal history is applied when the cooler 30 and the lower surface metal pattern 13 are bonded.

[0020] Next, the configurations of the cooler 30 and the insulating member 40 will be described. As shown in FIG. 2 , the cooler 30 is bonded to the sealing body 10. More specifically, the cooler 30 is bonded to the lower surface metal pattern 13 of the sealing body 10 via a bonding material 31. The bonding material 31 is, for example, thermal grease or solder. From the viewpoint of thermal conductivity, the bonding material 31 is preferably solder. Since it is preferable that the solder melts quickly, the solder contains, for example, bismuth (Bi) or indium (In). By containing bismuth (Bi) or indium (In), the melting point of the solder is lowered.

[0021] The cooler 30 is made of, for example, aluminum or copper. From the viewpoint of thermal conductivity, the cooler 30 is preferably made of copper. The cooler 30 preferably has a pin fin shape. This increases the surface area of ​​the cooling portion and improves cooling efficiency.

[0022] The cooler 30 includes fastening portions 32. The cooler 30 is fixed to a fixing object by the fastening portions 32. In the first embodiment, four fastening portions 32 are provided at the four corners of the cooler 30. The four fastening portions 32 are through holes. As will be described later, the cooler 30 is fixed by screws 33 that are passed through the through holes. The screws 33 may be bolts.

[0023] As shown in FIGS. 1, 3, and 4, the insulating member 40 is provided around the sealing body 10 and on the upper surface of the cooler 30. The insulating member 40 is made of heat-resistant PPS (Polyphenylene sulfide) or PBT (Polybutylene terephthalate). Laser welding in the manufacturing process of the semiconductor device 101 causes heat to be transmitted locally to the insulating member 40. For this reason, it is preferable that the insulating member 40 be made of highly heat-resistant PPS.

[0024] The insulating member 40 includes a wall-like protrusion 41. As shown in Figures 3 and 4, the wall-like protrusion 41 is provided between the fastening portion 32 and the terminal 20. The wall-like protrusion 41 is a barrier that spatially separates the fastening portion 32 from the terminal 20, for example, by surrounding the periphery of the fastening portion 32. The top of the wall-like protrusion 41 is higher than the top of the screw 33 that is passed through the fastening portion 32 of the cooler 30 (see Figure 6).

[0025] 6 is a front view showing the configuration of a power conversion device 201 according to Embodiment 1. The power conversion device 201 includes a semiconductor device 101, a housing 51, a capacitor 52, an external electrode 53, and a control board .

[0026] The housing 51 is made of, for example, aluminum. The semiconductor device 101 is fastened to the housing 51 by screws 33 that are passed through fastening portions 32 of the cooler 30. The fastening portions 32 and screws 33 of the cooler 30 are at earth potential.

[0027] From the viewpoint of reducing inductance, it is preferable that the capacitor 52 be disposed as close as possible to the cooler 30. For example, the capacitor 52 is disposed at a position 5 mm from the cooler 30, but this is not limitative.

[0028] The external electrode 53 extends from the capacitor 52 to the semiconductor device 101. The external electrode 53 electrically connects the capacitor 52 to the main terminal 20A of the semiconductor device 101. The external electrode 53 has a flat plate shape. The external electrode 53 is, for example, a bus bar.

[0029] The control board 54 is connected to the signal terminal 20 B. The control board 54 is, for example, an FR4 (Flame Retardant Type 4) board.

[0030] When the semiconductor device 101 is driven, a current flows through the terminal 20. If there is no insulator other than air between the terminal 20 protruding from the sealing material 16 and the screw 33 of the fastening portion 32, which is at earth potential, a discharge may occur between the terminal 20 and the screw 33. For this reason, it is necessary to increase the distance between the terminal 20 and the fastening portion 32, for example by providing the fastening portion 32 at the outermost part of the cooler 30.

[0031] In the semiconductor device 101 of the first embodiment, an insulating wall-like protrusion 41 is disposed between the fastening portion 32 and the terminal 20. Therefore, a creepage distance that bypasses the wall-like protrusion 41 is obtained. The long insulation distance shown in FIG. 4 is ensured by the bypass, preventing spatial discharge. The fastening portion 32 of the cooler 30 and the terminal 20 can be brought closer together, thereby realizing miniaturization of the semiconductor device 101 and the power conversion device 201. The fastening portion 32 of the cooler 30 and the sealing body 10 can also be brought closer together, thereby realizing miniaturization of the cooler 30. As a result, the distance between the capacitor 52 and the sealing body 10 can be reduced, thereby reducing the self-inductance to the capacitor 52.

[0032] To summarize the above, the semiconductor device 101 in the first embodiment includes a sealing body 10, terminals 20, a cooler 30, and an insulating member 40. The sealing body 10 contains a semiconductor element 14. The terminals 20 are electrically connected to the semiconductor element 14 and protrude from the sealing body 10. The cooler 30 is bonded to the sealing body 10. The insulating member 40 is provided around the sealing body 10 and on the upper surface of the cooler 30. The cooler 30 includes a fastening portion 32 for fixing the cooler 30. The insulating member 40 includes a wall-like protrusion 41 provided between the fastening portion 32 and the terminal 20.

[0033] Such a semiconductor device 101 prevents spatial discharge between the terminal 20 and the fastening portion 32, and alleviates factors that hinder miniaturization of the device size.

[0034] The semiconductor element 14 of the first embodiment may be a MOSFET formed of SiC. SiC-MOSFETs have low loss. When multiple semiconductor elements 14 are provided, thermal interference between the semiconductor elements 14 is reduced. The area of ​​the upper surface metal pattern 12 on which the semiconductor elements 14 are mounted can be reduced.

[0035] The semiconductor element 14 of the first embodiment may be an RC-IGBT. The IGBT and the freewheeling diode are integrated into one semiconductor chip. With this configuration, the semiconductor device 101 and the power conversion device 201 can be made smaller.

[0036] The insulating layer 11 of the first embodiment may be a ceramic substrate. ３ N ４ , AlN and Al ２ O ３ It is preferable that the insulating layer 11 contains any one of the materials listed above. By forming the insulating layer 11 from a material with high thermal conductivity, heat dissipation is improved. Therefore, multiple semiconductor elements 14 can be arranged close to each other.

[0037] The cooler 30 of the first embodiment preferably has a pin fin shape. When the semiconductor device 101 is cooled by water, the pin fin shape increases the contact area between the cooler 30 and the cooling water. This sufficiently increases the cooling capacity and improves heat dissipation. This allows multiple semiconductor elements 14 to be arranged close to each other.

[0038] The upper surface metal pattern 12 and the lower surface metal pattern 13 in the first embodiment are preferably made of copper. By forming the upper surface metal pattern 12 and the lower surface metal pattern 13 from a material with high thermal conductivity, heat dissipation is improved. Therefore, multiple semiconductor elements 14 can be arranged close to each other.

[0039] The terminals 20 in the first embodiment are bonded to the semiconductor element 14 via the bonding material 17B. Heat generated in the semiconductor element 14 is conducted to the terminals 20 via the bonding material 17B that is in contact with the top surface of the semiconductor element 14, and dissipated. Because of the improved heat dissipation, multiple semiconductor elements 14 can be arranged close to each other.

[0040] The above-described configuration achieves miniaturization of the semiconductor device 101 and the power conversion device 201. In the first embodiment, the number of sealing bodies 10 is one, but as shown in a sixth embodiment described below, two or more sealing bodies 10 may be provided in one cooler 30. That is, the semiconductor device 101 includes at least one sealing body 10.

[0041] Second Preferred Embodiment FIGS. 7 and 8 are diagrams showing the configuration of a semiconductor device 102 according to a second preferred embodiment.

[0042] The insulating member 40 includes a cylindrical protrusion 42 that extends upward from the upper surface of the insulating member 40. In a plan view, the cylindrical protrusion 42 is provided on the insulating member 40 inside the cooler 30. As shown in Fig. 8 , the control board 54 is fastened to the cylindrical protrusion 42 with a screw 55. The screw 55 may be a bolt.

[0043] The cylindrical protrusion 42, which is fastened to the control board 54, is provided inside the cooler 30. This allows the control board 54 to be made smaller than when the cylindrical protrusion 42 is provided outside the cooler 30. As a result, the power conversion device can be made smaller.

[0044] The cylindrical protrusions 42 improve the vibration resistance of the control board 54. In other words, the cylindrical protrusions 42 reduce the vertical deflection of the control board 54. For example, if the control board 54 deflects vertically due to vibrations of the power conversion device, the joints of the signal terminals 20B and the bent portions of the signal terminals 20B are likely to be damaged. In the second embodiment, the cylindrical protrusions 42 are disposed near the signal terminals 20B, which reduces the amplitude of the control board 54, i.e., the amount of deflection. As a result, reliability is improved.

[0045] Third Preferred Embodiment FIGS. 9 and 10 are diagrams showing the configuration of a semiconductor device 103 according to a third preferred embodiment.

[0046] The insulating member 40 includes elongated protrusions 43 extending upward from the upper surface of the insulating member 40. The tip of each elongated protrusion 43 is located above the signal terminal 20B. In a plan view, the elongated protrusions 43 are provided on the insulating member 40 inside the cooler 30. As shown in FIG. 10 , the tip of each elongated protrusion 43 is inserted into a hole provided in the control board 54. The elongated protrusions 43 facilitate positioning of the control board 54 during the manufacturing process.

[0047] Since the long protrusions 43 inserted into the holes of the control board 54 are provided inside the cooler 30, the control board 54 can be made smaller than when the long protrusions 43 are provided outside the cooler 30. As a result, the power conversion device can be made smaller.

[0048] In the third embodiment, two elongated protrusions 43 are provided, but the number of elongated protrusions 43 may be one or three or more. The tip of the elongated protrusion 43 may have a tapered shape. This improves the ease of inserting the elongated protrusion 43 into the control board 54 during the manufacturing process. The elongated protrusion 43 may have a cylindrical shape.

[0049] 11 is a diagram showing the configuration of a semiconductor device 103A according to the third embodiment. The insulating member 40 may include a lower protrusion 44 extending downward from the bottom surface of the insulating member 40. In the manufacturing process, the positions of the insulating member 40, the cooler 30, and the housing 51 are aligned based on the lower protrusion 44. This improves the positional accuracy of the insulating member 40, the cooler 30, and the housing 51.

[0050] Fourth Preferred Embodiment FIG. 12 is a diagram showing the configuration of a semiconductor device 104 according to a fourth preferred embodiment.

[0051] The main terminal 20A includes a joint 21 joined to an external electrode 53. The external electrode 53 is, for example, a bus bar. The external electrode 53 extends to the tip of the main terminal 20A, and the joint 21 is located at the tip of the main terminal 20A. The joint 21 has a weld mark formed by welding. In the manufacturing process of the semiconductor device 104, the main terminal 20A and the external electrode 53 are joined by laser welding. In this configuration, the main terminal 20A is joined to the external electrode 53 without using screws or joining material. Since the number of parts is reduced, the space required for joining is also reduced. As a result, the semiconductor device 104 and the power conversion device can be made smaller.

[0052] The insulating member 40 includes a support portion 45. The support portion 45 is provided below the main terminal 20A, standing from the insulating member 40, and supports the joint portion 21. The main terminal 20A is supported by the support portion 45 during the laser welding process in the manufacturing process. This makes it possible to join the external electrode 53 to the main terminal 20A while the external electrode 53 is pressed against the main terminal 20A. During welding, no jig is needed to fix the external electrode 53 and the main terminal 20A, which allows the length of the main terminal 20A to be reduced. As a result, the semiconductor device 104 and the power conversion device can be made smaller.

[0053] 13 is a diagram showing the configuration of a semiconductor device 104A according to the fourth embodiment. The semiconductor device 104A may include a metal plate 22 provided on the upper surface of the support portion 45. The metal plate 22 may be an insert electrode embedded in the insulating member 40. During welding, the external electrode 53, the main terminal 20A, and the metal plate 22 are joined together. Since the external electrode 53 and the main terminal 20A are firmly fixed at the joint 21, reliability against vibration is improved. Furthermore, the welding process is stable, improving assembly efficiency.

[0054] 14 is a diagram showing the configuration of a semiconductor device 105 according to a fifth embodiment. The semiconductor device 105 includes an insert electrode 56.

[0055] A portion of the insert electrode 56 is embedded in the support portion 45 of the insulating member 40. This fixes the insert electrode 56 to the insulating member 40. The portion embedded in the insulating member 40 is called an insert portion. The insert electrode 56 is produced by insert molding.

[0056] The main terminal 20A includes a joint 21 joined to the insert electrode 56. The joint 21 has a welding mark. In the manufacturing process of the semiconductor device 105, the main terminal 20A and the insert electrode 56 are joined by laser welding.

[0057] The insert electrode 56 and the external electrode 53 are fixed to the insulating member 40 by screws 57. The screws 57 may be bolts. The main terminal 20A is electrically connected to the external electrode 53 via the insert electrode 56. The external electrode 53 is, for example, a bus bar.

[0058] In this configuration, the distance from the insert portion to the joint 21 is shorter than the distance from the external electrode 53 to the joint 21. This reduces the amount of deflection of the terminal 20 during vibration, making it less likely that stress will be applied to the joint 21. Because the joint area can be reduced, the semiconductor device 105 and the power conversion device can be made smaller.

[0059] Since the insert electrode 56 and the external electrode 53 are fastened together by the screw 57, the assembly process for connecting the semiconductor device 105 and the external electrode 53 is facilitated.

[0060] 15 is a plan view showing the configuration of a semiconductor device 106 according to a sixth embodiment. The semiconductor device 106 includes a plurality of sealing bodies 10 (10A, 10B), a plurality of main terminals 20A (20A1, 20A2), and a plurality of insert electrodes 56 (56A, 56B).

[0061] A first sealing body 10A and a second sealing body 10B are provided as the multiple sealing bodies 10. Each of the first sealing body 10A and the second sealing body 10B has the same configuration as the sealing body 10 shown in the semiconductor device 106 according to any one of the first to fifth embodiments. The first sealing body 10A and the second sealing body 10B are joined to the cooler 30. An insulating member 40 is provided around the first sealing body 10A and the second sealing body 10B and on the upper surface of the cooler 30.

[0062] The multiple main terminals 20A include two first main terminals 20A1 and two second main terminals 20A2. One first main terminal 20A1 and one second main terminal 20A2 protrude from the first sealing body 10A. Similarly, one first main terminal 20A1 and one second main terminal 20A2 protrude from the second sealing body 10B. The potential of the first main terminal 20A1 of the first sealing body 10A is the same as the potential of the first main terminal 20A1 of the second sealing body 10B. The potential of the second main terminal 20A2 of the second sealing body 10B is the same as the potential of the second main terminal 20A2 of the second sealing body 10B.

[0063] A first insert electrode 56A and a second insert electrode 56B are provided as the multiple insert electrodes 56. A portion of the first insert electrode 56A and a portion of the second insert electrode 56B are embedded in the insulating member 40 (more specifically, in the support portion 45 erected from the insulating member 40), and are thereby fixed to the insulating member 40. The first insert electrode 56A and the second insert electrode 56B are aligned in the alignment direction of the main terminals 20A.

[0064] The first insert electrode 56A is joined to the first main terminal 20A1 of the first sealing body 10A and the first main terminal 20A1 of the second sealing body 10B, which are at the same potential. The second insert electrode 56B is joined to the second main terminal 20A2 of the first sealing body 10A and the second main terminal 20A2 of the second sealing body 10B, which are at the same potential.

[0065] FIG. 16 is a plan view showing the configuration of a power converter 206 according to the sixth embodiment. The power converter 206 includes a semiconductor device 106, a first external electrode 53A, a second external electrode 53B, and a capacitor 52. The first external electrode 53A and the second external electrode 53B extend from the capacitor 52 to the semiconductor device 106 and are arranged parallel to each other in a plan view. A first insert electrode 56A is arranged on an extension of the first external electrode 53A. A second insert electrode 56B is arranged on an extension of the second external electrode 53B. The first external electrode 53A is electrically connected to the first insert electrode 56A. The first external electrode 53A and the first insert electrode 56A are connected by a single connection portion (screw 57). The tip end of the first insert electrode 56A extending from the connection portion is bifurcated (not shown) and is joined to the first main terminal 20A1 of the first sealing body 10A and the first main terminal 20A1 of the second sealing body 10B. The second external electrode 53B is electrically connected to the second insert electrode 56B. The second external electrode 53B and the second insert electrode 56B are connected at one connection portion (screw 57). The tip side of the second insert electrode 56B extending from the connection portion is bifurcated (not shown), and is joined to the second main terminal 20A2 of the first sealing body 10A and the second main terminal 20A2 of the second sealing body 10B without interfering with the first insert electrode 56A. The first external electrode 53A and the second external electrode 53B are, for example, bus bars.

[0066] According to this configuration, the number of external electrodes 53 is reduced. Fig. 17 is a plan view showing the configuration of a power converter in a state in which the number of external electrodes 53 is not reduced. As is clear from a comparison between Fig. 16 and Fig. 17 , in the power converter 206 of embodiment 6, the space required for arranging the capacitor 52, the first external electrode 53A, and the second external electrode 53B is reduced. That is, the power converter 206 can be made smaller. Furthermore, since the first insert electrode 56A and the second insert electrode 56B are arranged on extensions of the first external electrode 53A and the second external electrode 53B, respectively, assembly is easier.

[0067] 18 and 19 are plan views showing the configuration of a power conversion device 207 according to a seventh embodiment. Fig. 18 shows the state of the power conversion device 207 before it is electrically connected to the capacitor 52. Fig. 19 shows the state of the power conversion device 207 after it is electrically connected to the capacitor 52.

[0068] The semiconductor device 107 included in the power conversion device 207 has the same configuration as the semiconductor device 106 of embodiment 6. The potential of the first main terminal 20A1 of the first sealing body 10A is the same as the potential of the first main terminal 20A1 of the second sealing body 10B. The potential of the second main terminal 20A2 of the second sealing body 10B is the same as the potential of the second main terminal 20A2 of the second sealing body 10B.

[0069] The power conversion device 207 includes a plurality of external electrodes 53. Here, the plurality of external electrodes 53 include a first external electrode 53A and a second external electrode 53B.

[0070] The first external electrode 53A and the second external electrode 53B extend from the capacitor 52 to the semiconductor device 107. Although not shown, the first external electrode 53A and the second external electrode 53B are parallel plates in a front view. That is, the first external electrode 53A and the second external electrode 53B have a flat plate shape arranged parallel to each other. In a plan view, most of the first external electrode 53A and the second external electrode 53B overlap each other. The first external electrode 53A and the second external electrode 53B are, for example, bus bars.

[0071] 19 , each of the first external electrode 53A and the second external electrode 53B has an L-shaped bent portion between the first insert electrode 56A and the second insert electrode 56B in a plan view. However, the first external electrode 53A is bent in the opposite direction to the bending direction of the second external electrode 53B. The tip of the bent portion of the first external electrode 53A is joined to the first insert electrode 56A. The tip of the bent portion of the second external electrode 53B is joined to the second insert electrode 56B.

[0072] The inductance is reduced by arranging the first external electrode 53A and the second external electrode 53B protruding from the capacitor 52 in parallel, thereby improving the electrical characteristics of the power conversion device 207.

[0073] 20 is a plan view showing the configuration of a power converter 208 according to an eighth embodiment. The power converter 208 differs from the power converter 207 according to the seventh embodiment in the shape of the external electrodes 53.

[0074] The semiconductor device 108 included in the power conversion device 208 has the same configuration as the semiconductor device 107 of the seventh embodiment. The potential of the first main terminal 20A1 of the first sealing body 10A is the same as the potential of the first main terminal 20A1 of the second sealing body 10B. The potential of the second main terminal 20A2 of the second sealing body 10B is the same as the potential of the second main terminal 20A2 of the second sealing body 10B.

[0075] The first external electrode 53A extends from the capacitor 52 and connects to the first insert electrode 56A. The second external electrode 53B extends from the capacitor 52 and connects to the second insert electrode 56B. Although not shown, the first external electrode 53A and the second external electrode 53B are parallel flat plates in a front view. That is, the first external electrode 53A and the second external electrode 53B have flat plate shapes arranged parallel to each other. The first external electrode 53A and the second external electrode 53B are, for example, bus bars.

[0076] Each of the first external electrode 53A and the second external electrode 53B has an L-shape in plan view. The base end, which is wider than the tip end of the L-shape, is provided on the capacitor 52 side, i.e., in front of the first insert electrode 56A and the second insert electrode 56B. The base end of the first external electrode 53A and the base end of the second external electrode 53B overlap each other in plan view. The tip end of the first external electrode 53A extends from the base end of the first external electrode 53A and is joined to the first insert electrode 56A. The tip end of the second external electrode 53B extends from the base end of the second external electrode 53B and is joined to the second insert electrode 56B.

[0077] The first external electrode 53A and the second external electrode 53B protruding from the capacitor 52 are arranged in parallel, thereby reducing inductance and improving the electrical characteristics of the power conversion device 208. Furthermore, the lengths of the first external electrode 53A and the second external electrode 53B are shortened, thereby realizing a more compact power conversion device 208.

[0078] 21 is an electrical circuit diagram of a semiconductor device 109 according to a ninth embodiment. The semiconductor elements are connected by a 2-in-1 connection. The number of electrodes can be reduced, simplifying the wiring of the bus bars that are the external electrodes 53. The distance from the capacitor 52 to the semiconductor device 109 is shortened, thereby realizing a more compact power conversion device.

[0079] Tenth Preferred Embodiment Fig. 22 is a front view showing the configuration of a semiconductor device 110 according to a tenth preferred embodiment. Fig. 23 is a bottom view showing the configuration of the semiconductor device 110.

[0080] The semiconductor device 110 includes a sealing material protrusion 16A provided on the lower surface of the sealing body 10. The sealing material protrusion 16A is formed by the sealing material 16 protruding downward. The sealing material protrusion 16A is provided around the lower surface metal pattern 13.

[0081] In the manufacturing process, the positioning accuracy is improved when joining the sealing body 10 and the cooler 30. There is no need to provide extra space in the cooler 30 to allow for misalignment. The semiconductor device 110 and the power conversion device can be made smaller.

[0082] 24 is a functional block diagram showing the configuration of a power conversion system according to an eleventh embodiment. The power conversion system includes a power supply 310, a power conversion device 320, and a load 330. The power conversion device 320 includes the semiconductor device described in any one of the first to tenth embodiments. The power conversion device 320 of the eleventh embodiment is not limited to a specific power conversion device, but will be described here using a three-phase inverter as an example.

[0083] The power supply 310 is a DC power supply. The power supply 310 supplies DC power to the power conversion device 320. The power supply 310 is, for example, a DC system, a solar cell, a storage battery, or the like. The power supply 310 may be a DC / DC converter that converts DC power output from a DC system into predetermined power. The power supply 310 may also be a rectifier circuit connected to an AC system, an AC / DC converter, or the like.

[0084] The power conversion device 320 is connected to the power supply 310 and the load 330. The power conversion device 320 converts the DC power supplied from the power supply 310 into AC power. The power conversion device 320 supplies the AC power to the load 330.

[0085] The load 330 is driven by the AC power supplied from the power conversion device 320. The load 330 is, for example, a three-phase motor. The three-phase motor is not limited to a specific application. The three-phase motor is mounted in various electrical devices. For example, the three-phase motor is mounted in hybrid vehicles, electric vehicles, railroad cars, elevators, air conditioning equipment, etc.

[0086] The following describes in detail the power conversion device 320. The power conversion device 320 includes a main conversion circuit 321, a drive circuit 322, and a control circuit 323.

[0087] The main conversion circuit 321 includes a semiconductor device described in any one of the first to tenth embodiments. The semiconductor device configures a two-level three-phase full-bridge circuit (not shown). The three-phase full-bridge circuit includes six switching elements (not shown) and six freewheeling diodes (not shown). At least one of the switching elements and freewheeling diodes corresponds to the semiconductor element 14 included in the semiconductor device described in any one of the first to tenth embodiments.

[0088] The three-phase full-bridge circuit includes three upper arms (not shown) and three lower arms (not shown). Each of the upper and lower arms includes one switching element and one freewheeling diode connected in anti-parallel to the switching element. The switching element included in one upper arm is connected in series to the switching element included in one lower arm, forming a pair of upper and lower arms. In other words, the three-phase full-bridge circuit includes three pairs of upper and lower arms. The three pairs of upper and lower arms correspond to the U, V, and W phases of the three-phase full-bridge circuit, respectively. The output terminals of the three pairs of upper and lower arms, i.e., the three output terminals of the main conversion circuit 321, are connected to the load 330.

[0089] The main conversion circuit 321 converts DC power supplied from the power supply 310 into AC power by the switching operation of the switching element. The main conversion circuit 321 supplies the AC power to the load 330 via the output terminal.

[0090] The drive circuit 322 generates a drive signal for driving the switching element of the main conversion circuit 321 in accordance with a control signal output from the control circuit 323. The drive circuit 322 supplies the drive signal to the control electrode of the switching element of the main conversion circuit 321.

[0091] The drive signal is a signal for turning on a switching element or a signal for turning off a switching element. More specifically, when a switching element is maintained in an on state, the drive signal is a voltage signal (on signal) that is equal to or greater than the threshold voltage of the switching element. When a switching element is maintained in an off state, the drive signal is a voltage signal (off signal) that is smaller than the threshold voltage of the switching element.

[0092] The control circuit 323 outputs a control signal to the drive circuit 322 for controlling the drive circuit 322. At that time, the control circuit 323 calculates the time (on time) for which each switching element of the main conversion circuit 321 should be in the on state based on the power to be supplied to the load 330, and generates the control signal. In other words, the control circuit 323 generates a control signal so that the main conversion circuit 321 is controlled by PWM (Pulse Width Modulation). The control circuit 323 outputs a control signal to the drive circuit 322 so that the drive circuit 322 outputs an on signal to switching elements that should be in the on state and an off signal to switching elements that should be in the off state. In this way, the control circuit 323 controls the switching elements of the main conversion circuit 321 so that a predetermined power is supplied to the load 330.

[0093] Since the semiconductor device according to any one of the first to tenth embodiments is applied to the main conversion circuit 321, improved reliability and a reduced device size are achieved.

[0094] In the eleventh embodiment, an example has been shown in which the power conversion device 320 is a two-level three-phase inverter, but the configuration of the power conversion device 320 is not limited thereto. For example, the power conversion device 320 may be a multi-level power conversion device, such as a three-level power conversion device. Alternatively, the power conversion device 320 may be a single-phase inverter for supplying power to a single-phase load. When the load 330 is a DC load, the power conversion device 320 may be a DC / DC converter or an AC / DC converter. When the load 330 is a solar power generation system, a power storage system, or the like, the power conversion device 320 may be a power conditioner.

[0095] Although the eleventh embodiment shows an example in which the load 330 is a three-phase motor, the configuration of the load 330 is not limited to this. For example, the load 330 may be an electric discharge machine, a laser processing machine, an induction heating cooker, or a non-contact power supply system.

[0096] Although this disclosure has been described in detail, the above description is illustrative in all respects and is not restrictive. It is understood that countless variations not illustrated can be envisioned.

[0097] It should be noted that the embodiments can be freely combined, and the embodiments can be modified or omitted as appropriate.

[0098] 10 Sealing body, 10A First sealing body, 10B Second sealing body, 11 Insulating layer, 12 Upper surface metal pattern, 13 Lower surface metal pattern, 14 Semiconductor element, 15 Wire, 16 Sealing material, 16A Sealing material protrusion, 17A Bonding material, 17B Bonding material, 20 Terminal, 20A Main terminal, 20A1 First main terminal, 20A2 Second main terminal, 20B Signal terminal, 21 Bonding portion, 22 Metal plate, 23 Screw, 30 Cooler, 31 Bonding material, 32 Fastening portion, 33 Screw, 40 Insulating member, 41 Wall-shaped protrusion, 42 Cylindrical protrusion, 43 Elongated protrusion, 44 Lower protrusion, 45 Support portion, 51 Housing, 52 Capacitor, 53 External electrode, 53A First external electrode, 53B Second external electrode, 54 Control board, 55 Screw, 56 Insert electrode, 56A First insert electrode, 56B Second insert electrode, 57 Screw, 101 to 110 Semiconductor device, 201 to 208 Power conversion device, 310 Power supply, 320 Power conversion device, 321 Main conversion circuit, 322 Drive circuit, 323 Control circuit, 330 Load.

Claims

1. A semiconductor device comprising: at least one sealing body containing a semiconductor element; terminals electrically connected to the semiconductor element and protruding from the at least one sealing body; a cooler joined to the at least one sealing body; and an insulating member provided around the at least one sealing body and on the upper surface of the cooler, wherein the cooler includes a fastening portion for fixing the cooler, and the insulating member includes a wall-like protrusion portion provided between the fastening portion and the terminal.

2. The semiconductor device according to claim 1, wherein said insulating member includes a cylindrical protrusion extending upward from an upper surface of said insulating member.

3. The semiconductor device according to claim 1, further comprising a signal terminal electrically connected to the semiconductor element and protruding from the at least one sealing body, wherein the insulating member includes elongated protrusions, and the tip of each of the elongated protrusions is positioned higher than the signal terminal.

4. The semiconductor device according to claim 1, wherein said insulating member includes a lower protrusion extending downward from a lower surface of said insulating member.

5. The semiconductor device according to claim 1, wherein the terminal includes a joint portion joined to an external electrode, and the joint portion has a welding mark.

6. The semiconductor device according to claim 5, wherein the insulating member includes a support portion that is provided below the terminal and supports the joint portion.

7. The semiconductor device according to claim 6, further comprising a metal plate provided on the upper surface of said support portion.

8. The semiconductor device according to claim 1, further comprising an insert electrode fixed to said insulating member, wherein said terminal includes a joint joined to said insert electrode, and said joint has a welding mark.

9. The semiconductor device according to claim 8, wherein the insert electrode is fastened to an external electrode by a screw, and the terminal is electrically connected to the external electrode via the insert electrode.

10. The semiconductor device described in claim 1, further comprising an insert electrode fixed to the insulating member, wherein the at least one sealing body is a plurality of sealing bodies including a first sealing body and a second sealing body, and the insert electrode is connected to the terminal protruding from the first sealing body and the terminal protruding from the second sealing body, which are at the same potential.

11. The semiconductor device according to claim 1, further comprising a plurality of insert electrodes fixed to said insulating member, said plurality of insert electrodes being aligned in the direction in which said terminals are aligned.

12. The semiconductor device according to claim 1, wherein the semiconductor element is a MOSFET formed of SiC.

13. The semiconductor device according to claim 1, wherein the semiconductor element is an RC-IGBT.

14. The at least one encapsulant includes an insulating layer, an upper surface metal pattern provided on an upper surface of the insulating layer and to which the semiconductor element is bonded, and a lower surface metal pattern provided on a lower surface of the insulating layer and exposed from a lower surface of the at least one encapsulant, the insulating layer being a ceramic substrate, and the ceramic substrate being made of Si ３ N ４ , AlN and Al ２ O ３ The semiconductor device according to claim 1 , wherein the semiconductor device comprises any one of the following materials:

15. The semiconductor device according to claim 1, wherein the cooler has a pin fin shape.

16. The semiconductor device according to claim 14, wherein the upper surface metal pattern and the lower surface metal pattern are formed of copper.

17. The semiconductor device according to claim 1, wherein the terminal is bonded to the semiconductor element via a bonding material.

18. A power conversion device further comprising: a semiconductor device as described in claim 1; a plurality of insert electrodes including a first insert electrode and a second insert electrode fixed to the insulating member; and a plurality of external electrodes including a first external electrode and a second external electrode having a flat plate shape arranged parallel to each other, wherein each of the first external electrode and the second external electrode has a bent portion that bends in an L-shape between the first insert electrode and the second insert electrode in a planar view, and the first external electrode is bent in a direction opposite to the bending direction of the second external electrode.

19. A power conversion device further comprising: a semiconductor device as described in claim 1; a plurality of insert electrodes including a first insert electrode and a second insert electrode fixed to the insulating member; and a plurality of external electrodes including a first external electrode and a second external electrode having a flat plate shape arranged parallel to each other, wherein each of the first external electrode and the second external electrode has an L-shape in a plan view, and a base end wider than the tip end of the L-shape is provided in front of the first insert electrode and the second insert electrode.

20. The semiconductor device according to claim 1, wherein said semiconductor element is connected by a 2-in-1 connection.

21. The semiconductor device according to claim 1, further comprising an encapsulant protrusion provided on the underside of said at least one encapsulant.