JP2019197842A - Power module, electric power conversion system, and method of manufacturing power module - Google Patents

Abstract

To provide a power module that can be made void-less by improving sealing-resin injection properties and has high reliability, an electric power conversion system, and a method of manufacturing the power module.SOLUTION: A power module comprises: power semiconductor elements 21, 22 arranged on a ceramic substrate 10; a power semiconductor element 21 and a power semiconductor element 22; a plate-like source electrode plate 611 and a drain electrode plate 612 having two or more connection parts for connecting the power semiconductor element 21 and an inner pad 62a of a screw-fitted electrode 621, or the ceramic substrate 10 and an inner pad 62b of a screw-fitted electrode 622; resin-molding parts 601, 602 provided at center parts of adjacent connection parts of the source electrode part 611 and drain electrode plate 612 to be inclined convexly toward a reverse side and in a rod shape in a width direction for the ceramic substrate 10; and a sealing resin part 7 sealing peripheries of the connection parts.SELECTED DRAWING: Figure 2

Description

  The present application relates to a power module in which a mounting substrate is sealed with a sealing resin, a power conversion device, and a method for manufacturing the power module.

  As an insulating seal for a power module, a direct potting (hereinafter referred to as DP) sealing technique that does not require a mold and enables high heat-resistant epoxy sealing is becoming widespread. Since the viscosity is higher than that of a general silicone gel sealing material, there is a problem that injection into a narrow gap is difficult, and voids that affect the insulation characteristics and long-term reliability are difficult to come off.

  In the case of a module having a structure in which an electrode plate that realizes high reliability is directly connected to a power semiconductor element, there is a concern that reliability may be impaired by thermal stress due to a difference in expansion coefficient between copper of the electrode plate and the ceramic substrate and the power semiconductor element. Therefore, it was necessary to secure the thickness of the joint and reduce the strain. Further, since the electrode plate has a large area and has a parallel plate structure with the insulating substrate on which the semiconductor element is mounted, voids are particularly difficult to escape in a narrow gap. As a countermeasure, an injection device in a vacuum is used. However, the device is large, and there are still problems in terms of productivity, for example, time is required for decompression and spreading of the resin.

  On the other hand, in Patent Document 1, a step is provided at a position higher than the joint surface with the semiconductor element to increase the gap, and further, an opening is formed to improve the DP resin injecting property. It is intended to suppress formation. In Patent Document 2, an inclined portion is installed in a resin filling space between the side wall of the case and the end portion of the mounting substrate, and DP resin is to be filled into the case through the inclined portion. .

JP 2006-202885 A (paragraphs 0015 to 0020, FIG. 1) Japanese Patent Laying-Open No. 2011-211107 (paragraphs 0012 to 0016, FIG. 1)

  However, even if the conventional technology as described above is used, the air once trapped between the parallel plates is difficult to move, and even if the gap is enlarged or there is an opening, the air remains and the void cannot be sufficiently removed. There was a problem.

  The present application discloses a technique for solving the above-described problems, and realizes a voidless by improving the injection property of the sealing resin, and a highly reliable power module, power converter, and power It aims at obtaining the manufacturing method of a module.

  A power module disclosed in the present application includes a semiconductor element disposed on a substrate and two or more connection portions for connecting the semiconductor elements to each other, the semiconductor element and an external terminal, or the substrate and the external terminal. A plate-shaped electrode plate, a resin-molded portion that is convex and inclined on the substrate surface side between the connecting portions adjacent to the electrode plate, and a sealing resin portion that seals the periphery of the connecting portion And.

  The method for manufacturing a power module disclosed in the present application includes a step of mounting a semiconductor element on a substrate and a resin molding in which a convex and inclined surface is provided on the substrate surface side between connecting portions of plate-like electrode plates. Forming a portion and connecting the electrode plate to the semiconductor element, and forming a sealing resin portion for sealing the connection portion between the semiconductor element and the electrode plate.

  According to the present application, the center back surface between the connection of the plate-like electrode plates is provided with a resin molded portion provided with a convex shape and an inclination, so that a voidless is realized by improving the injection property of the sealing resin, Reliability can be improved.

1 is a perspective view showing a configuration of a power module according to Embodiment 1. FIG. 1 is a cross-sectional view showing a configuration of a power module according to a first embodiment. 5 is a cross-sectional view showing the method for manufacturing the power module according to Embodiment 1. FIG. 5 is a perspective view showing a method for manufacturing the power module according to Embodiment 1. FIG. It is sectional drawing which shows the other manufacturing method of the power module by Embodiment 1. It is sectional drawing which shows the other structure of the power module by Embodiment 1. It is sectional drawing which shows the other structure of the power module by Embodiment 1. It is sectional drawing which shows the other structure of the power module by Embodiment 1. It is a perspective view which shows the structure of the power module by Embodiment 2. FIG. It is sectional drawing which shows the structure of the power module by Embodiment 2. FIG. FIG. 10 is a perspective view showing a method for manufacturing a power module according to Embodiment 2. It is a block diagram which shows the structure of the power conversion system to which the power converter device by Embodiment 3 is applied.

Embodiment 1 FIG.
FIG. 1 is a perspective view showing a configuration of a power module 101 according to Embodiment 1, and FIG. 2 is a cross-sectional view taken along arrow AA in FIG. As shown in FIGS. 1 and 2, the power module 101 is electrically connected to a ceramic substrate 10 that is an insulating substrate, power semiconductor elements 21 and 22 disposed on the ceramic substrate 10, and electrodes of the power semiconductor elements 21 and 22. A source electrode plate 611 serving as a main terminal connected to the semiconductor substrate 10, a drain electrode plate 612 serving as a main terminal electrically connected to the copper conductor layer 13 of the ceramic substrate 10, the power semiconductor element 22, and electricity via the wires 4. Signal terminals 630 to be connected to each other, and a sealing resin portion 7 that seals the periphery of the power semiconductor elements 21 and 22 and their connected portions.

  The ceramic substrate 10 is provided with copper conductor layers 12 and 13 (pattern thickness 0.4 mm) on both surfaces of an AlN ceramic substrate 11 (40 mm × 25 mm × thickness 0.635 mm). Power semiconductor elements 21 and 22 are disposed on the copper conductor layer 13 on the surface of the ceramic substrate 10.

  As the power semiconductor elements 21 and 22, a diode 21 (Diode, 15 mm × 15 mm × thickness 0.3 mm) and an IGBT 22 (Insulated Gate Bipolar Transistor, 15 mm × 15 mm × thickness 0.3 mm) are respectively formed by solder die bonding 3. Bonded on the copper conductor layer 13 on the surface of the ceramic substrate 10.

  The source electrode plate 611 and the drain electrode plate 612 are copper plate-like electrodes (thickness 0.3 mm, source electrode plate: width 8 mm, drain electrode plate: width 4 mm), and are formed by an insert mold method. They are connected by a molding part 601 and fixed to the case 5 by a resin molding part 601. The source electrode plate 611 has a resin molded portion 602 formed between the diode 21 and the IGBT 22 and is fixed to the case 5 by the resin molded portion 602. One end of the source electrode plate 611 is electrically connected to the source electrodes 211 and 221 through which large currents of the power semiconductor elements of the diode 21 and the IGBT 22 flow, and the other end as an external terminal. The copper screwing electrode 621 (thickness 0.8 mm, width 5 mm) formed on the outer periphery of the case 5 is electrically connected by a solder joint 33a. On the other hand, one end of the drain electrode plate 612 is electrically connected to the copper conductor layer 13 of the ceramic substrate 10 by a solder joint, and the other end is electrically connected to the screw electrode 622 by a solder joint. The signal terminals 630 (631, 632, 633) formed in the case 5 are connected to the internal pads 63 (63a, 63b, 63c) of the signal terminals 630 (631, 632, 633), the gate electrodes 222a, 222b of the IGBT 22, and the temperature. The sensor electrode 222c is electrically connected to each other by an aluminum wire (φ0.15 mm) 4.

  The case 5 is made of PPS (Polyphenylene Sulfide) resin (48 mm × 28 mm × height 12 mm), is formed in a frame shape, and is fixed to the edge of the ceramic substrate 10 using an adhesive 8 made of silicone. Yes. The case 5 surrounds the sealing resin portion 7, and the adhesive 8 fills the gap between the case 5 and the ceramic substrate 10, so that the resin when forming the sealing resin portion 7 using direct potting is used. Prevents leakage.

  The resin molding parts 601 and 602 are made of PPS resin, and the vertical cross section in the longitudinal direction is formed into a convex V-shape on the ceramic substrate surface side with respect to the rectangular ceramic substrate 10. The resin molding portion 601 straddles the central portion of the source electrode plate 611 that straddles the internal pad 62a of the screwing electrode 621 and the diode 21, and straddles the internal pad 62b of the screwing electrode 622 and the copper conductor layer 13 on the ceramic substrate 10. The drain electrode plate 612 is provided in a bar shape in the short direction of the ceramic substrate 10 so as to connect the central portion of the drain electrode plate 612. The resin molding portion 602 is provided in a bar shape in the short direction of the ceramic substrate 10 at the central portion of the source electrode plate 611 straddling the diode 21 and the IGBT 22. Both ends 601a, 601b, and 602a, 602b of the resin molding parts 601 and 602 are fitted and fixed to the recesses 51a, 51b, and 52a, 52b, respectively, provided in the upper part of the side surface in the longitudinal direction of the rectangular case 5. The source electrode plate 611 and the drain electrode plate 612 are positioned. In addition, although the resin molding parts 601 and 602 are V-shaped convex on the ceramic substrate surface side, the present invention is not limited to this. It is only necessary that the slope is formed in a convex shape on the ceramic substrate surface side. For example, a convex U-shape may be formed on the ceramic substrate surface side. Moreover, although the vertical cross section in the longitudinal direction with respect to the ceramic substrate 10 is a convex V-shape on the ceramic substrate surface side, it is not limited to this. For example, the vertical cross section in the short direction with respect to the ceramic substrate 10 may be a V-shape that is convex on the ceramic substrate surface side.

  In the power module 101 of the first embodiment, since the bottom surfaces of the resin molded portions 601 and 602 have a convex V-shaped cross section, the space between the ceramic substrate 10 and the ceramic substrate 10 becomes closer to the end in the short direction. The structure becomes thicker. Therefore, in the resin molding parts 601 and 602, the bubbles that have entered the lower surface during manufacturing move toward the end without staying in place, and are discharged to the outside of the resin molding parts 601 and 602 from the liquid surface. It will be released to the outside. In addition, the resin molded portions 601 and 602 are positioned with respect to the case 5 so that the distance between the source electrode plate 611 and the drain electrode plate 612 and the ceramic substrate 10 and the power semiconductor element (diode 21, IGBT 22) is a constant distance. By being held in this position, thermal stress can be reduced, and the injection property of the sealing resin can be improved.

  Next, a method for manufacturing the power module 101 according to Embodiment 1 will be described with reference to FIG. FIG. 3A to FIG. 3C are cross-sectional views showing the manufacturing process of the power module 101 according to the first embodiment.

  First, as shown in FIG. 3 (a), plate-like solders 31a and 31b are used to be positioned and mounted on the ceramic substrate 10 so as to overlap with the diodes 21 and IGBTs 22, respectively, and solder 31a, 31b is heated and melted to perform solder die bonding.

  Subsequently, as shown in FIG. 3B, a silicone adhesive 8 is applied to the inner peripheral portion of the case 5, the ceramic substrate 10 is positioned and mounted, and heated in an oven at 50 ° C. to 150 ° C. for 30 minutes. Then, the adhesive 8 is cured.

  Next, as shown in FIG. 3C, cream-like solders 32 a and 32 b are respectively connected to positions where the source electrodes 211 and 221 of the diode 21 and the IGBT 22 and the drain electrode plate 612 (not shown) of the copper conductor layer 13 are connected. , 32c are dispensed, and cream-like solders 33a, 33b are dispensed to the internal pads 62a, 62b of the screwing electrodes 621, 622.

  FIG. 4 is a perspective view corresponding to FIG. 3C, but the resin molding provided on the source electrode plate 611 and the drain electrode plate 612 after dispensing the solders 32a, 32b, 32c, 33a, and 33b. Each of the source electrodes of the diode 21 and the IGBT 22 is positioned by fitting both ends 601a, 601b and 602a, 602b of the portions 601 and 602 into the recesses 51a, 51b and 52a and 52b of the case 5 shown in FIG. 211, 221 and the internal electrodes 62a, 62b of the screwing electrodes 621, 622, and by heating and melting the solder, the diode 21, the IGBT 22, the screwing electrode 621, and the copper conductor layer 13 on the ceramic substrate 10 A circuit is formed by electrically connecting the screwing electrode 622.

  Finally, using the wires 4 (4a, 4b, 4c), the gate electrodes 222a, 222b and the temperature sensor electrode 222c of the IGBT 22 and the internal pads 63 (63a, 63b) of the signal terminals 630 (631, 632, 633) of the case 5 are used. , 63c) are connected by wire bonds, respectively. Thereafter, the direct potting sealing resin is poured in a state heated to 40 ° C. to 90 ° C., vacuum degassed, heated (held at 50 ° C. to 200 ° C. for a predetermined time) and cured to form the sealing resin portion 7. Thus, the power module 101 shown in FIG. 2 is completed.

  Direct potting sealing resin (viscosity: 5 Pa · S to 30 Pa · S) used for sealing is higher in viscosity than silicone gel (viscosity: 0.2 Pa · S to 2 Pa · S), so it entraps air. It is easy and easy to remove. Bubbles taken into the lower surfaces of the source electrode plate and the drain electrode plate try to float on the liquid surface due to the influence of gravity (buoyancy). When the source electrode plate and the drain electrode plate are flat plates, the source electrode plate and the drain electrode There is concern about the possibility of remaining on the lower surface of the electrode plate.

  On the other hand, in the power module 101 of the first embodiment, since the bottom surfaces of the resin molded portions 601 and 602 have a convex V-shaped cross section, the space between the ceramic substrate 10 and the resin molded portion 601, The thickness of the sealing resin portion increases toward the end in the short direction of 602. Therefore, in the resin molding parts 601 and 602, the bubbles that have entered the lower surface during manufacturing move toward the end without staying in place, and are discharged to the outside of the resin molding parts 601 and 602 from the liquid surface. It will be released to the outside. Further, since the direct potting sealing resin has a tendency to decrease in viscosity as the temperature becomes higher, the effect of facilitating removal of bubbles by heating using a plate-type heater or oven after injection is obtained. Also, for example, the movement of bubbles can be activated by giving vibration and shock to the case 5 placed on an electric vibrator, or the volume of the bubbles can be increased by reducing the pressure by putting it in a vacuum desiccator. Thus, bubbles are more easily removed by facilitating movement of the direct potting sealing resin to a larger thickness.

  In the first embodiment, the resin molded portions 601 and 602 are formed by insert molding with a plurality of electrode plates. However, the present invention is not limited to this. The same effect can be obtained even if the resin molding parts 601 and 602 are configured by forming them with insulating adhesives 691 and 692 as shown in FIG.

  Moreover, although a part (end part) of the resin molding parts 601 and 602 was fitted and fixed to the recessed parts 51a and 51b and 52a and 52b of the case 5, it is not restricted to this. As shown in FIG. 6, a part of the resin molding parts 601 and 602 is fitted into the pattern of the copper conductor layer 13 of the ceramic substrate 10 and fixed to the ceramic substrate 10, whereby the source electrode plate 611 and the drain electrode The plate 612 can maintain a constant distance with respect to the diode 21, the IGBT 22, and the ceramic substrate 10, eliminates damage caused by the contact of the source electrode plate 611 with the surface electrode of the diode 21 and the IGBT 22, and is displaced. If the amount of the supplied solders 32 and 33 is constant, the protrusion and the open failure are unlikely to occur, and the sealing resin is easily injected. In this case, the vertical cross section in the longitudinal direction of the ceramic substrate 10 is inclined in a convex U-shape on the ceramic substrate surface side, but is not limited thereto. For example, the vertical cross section in the short direction of the ceramic substrate 10 can be inclined in a convex U shape on the ceramic substrate surface side. Further, the same effect can be obtained by mounting on an insulating portion of a ceramic substrate as shown in FIG. 7 or outsert (insertion and fixing) with respect to a case by an electrode plate alone as shown in FIG. .

  PPS is used as the material of the resin molding parts 601 and 602. However, since this is cheaper than the sealing resin, it is effective in reducing the cost by reducing the amount of the sealing resin.

  The source electrode plate 611 is made of copper and has an expansion coefficient of about 17 ppm / K, whereas the diode 21, the IGBT 22, and the ceramic substrate 10 are as small as 3 to 7 ppm / K. Therefore, cooling after heating for solder bonding is performed. Thermal stresses are generated by temperature cycles in time and actual use environment. Therefore, it is desirable to make the source electrode plate 611 as thin as possible within the range of the current capacity to be used. On the other hand, since the screwing electrode 621 needs to withstand the fastening force of the screw, it needs a certain thickness. The source electrode plate 611 is preferably made of surface metallization such as nickel and silver having excellent solderability, but the screw electrodes 620 (621, 622) are preferably left as copper having excellent weather resistance. There are also different thickness copper plates with different thicknesses depending on the location, and partially plated copper plates with different metallizations depending on the location. However, the source electrode plate 611 and the screw electrode 620 are separate members because they are often expensive and poorly available. There are many benefits.

  Regarding the reduction of the thermal stress due to this difference in expansion coefficient, the resin molded portions 601 and 602 are fitted and fixed to the recesses 51a, 51b and 52a, 52b of the case 5, thereby fixing the source electrode plate 611 and the drain. The electrode plate 612 maintains the distance between the diode 21, the IGBT 22, and the ceramic substrate 10 at a constant distance, thereby reducing thermal stress and improving the injectability of the sealing resin.

  The pattern of the source electrode plate 611 or the drain electrode plate 612 may change depending on the capacity and shape of the diode 21 and the IGBT 22 to be mounted, and the pattern can be replaced by wire bonding. It is effective that the electrode plate 612 and the screwing electrode 620 are separate members.

  As a method for supplying the solder 32a and 32b, cream-like solder was used, but it is also possible to take a method of sandwiching plate-like solder and reflowing. Further, the same effect can be obtained by pouring molten solder from openings 65a and 65b opened in portions corresponding to the source electrode 211 and 221 of the diode 21 and the IGBT 22 of the source electrode plate 611.

  AlN was used as the base material of the ceramic substrate 10, but the same effect can be obtained with ceramic materials such as alumina and SiN. Furthermore, when there is not much need for heat dissipation, a metal base substrate or a glass epoxy substrate can be used. Further, although PPS is used as the material of the case 5, the same effect can be obtained by using LCP (Liquid Crystal Polymer) having higher heat resistance.

  Although the copper plate is used as the material of the source electrode plate 611, the weight can be reduced by using a copper-plated aluminum plate, and the ceramic substrate can be obtained by using a CIC (Copper Invar Copper) plate in which copper and invar are superimposed. It is also possible to reduce the thermal stress by suppressing the difference in expansion coefficient from 10 and improve the reliability.

  As the module configuration, the diode 21 and the IGBT 22 use one pair of 1 in 1, but the same effect can be obtained even if two pairs of 2 in 1 or six pairs of 6 in 1 are used. Further, although the aluminum wire 4 is used here, the same effect can be obtained by using a copper wire, an aluminum-coated copper wire, or a gold wire. Moreover, about the direct potting sealing resin, the same effect is acquired even if it is a kind which is poured and cured at room temperature. Solder was used for the connection between the diode 21 and IGBT 22 and the ceramic substrate 10, the connection between the diode 21 and IGBT 22 and the source electrode plate 611, and the connection between the ceramic substrate 10 and the drain electrode plate 612, but the Ag filler was dispersed in the epoxy resin. The same effect can be obtained by using a conductive adhesive or an Ag nanopowder or a Cu nanopowder in which nanoparticles are fired at a low temperature. Further, the same effect can be obtained in a transfer mold package that is sealed by a transfer mold sealing resin using a mold without using the case 5.

  As described above, according to the power module 101 of the first embodiment, the power semiconductor element (diode 21, IGBT 22), the power semiconductor element (diode) 21, and the power semiconductor element (IGBT) arranged on the ceramic substrate 10. 22. A plate-like source electrode plate having two or more connecting portions for connecting the power semiconductor element (diode) 21 and the internal pad 62a of the screwing electrode 621 or the ceramic substrate 10 and the internal pad 62b of the screwing electrode 622 611 and the drain electrode plate 612 and a central portion between adjacent connection portions of the source electrode plate 611 and the drain electrode plate 612 are provided with a convex and inclined surface on the back side, and in a bar shape in the short direction with respect to the ceramic substrate 10. Resin molding parts 601 and 602 provided, and a sealing resin part 7 for sealing the periphery of the connection part Since so provided, realized voidless by improving the injection of the sealing resin, it is possible to improve the reliability. Further, since 601 and 602 are fixed to the ceramic substrate 10 or fixed to the case 5 fixed to the ceramic substrate 10, the distance between the ceramic substrate and the power semiconductor element is kept at a constant distance. Thus, it is possible to reduce thermal stress.

Embodiment 2. FIG.
In the first embodiment, resin molded portions are used for the source electrode plate 611 and the drain electrode plate 612 as main terminals. In the second embodiment, a case where a resin molded portion is also used for signal terminals will be described.

  FIG. 9 is a perspective view showing the configuration of the power module 102 according to the second embodiment, and FIG. 10 is a cross-sectional view taken along the line BB in FIG. As shown in FIGS. 9 and 10, in the second embodiment, the power module 102 connects the IGBT 22 and the signal terminal 630 with a copper plate-like signal electrode plate (thickness 0.15 mm, Width 0.3 mm) 613 is used.

  The signal electrode plate 613 (613a, 613b, 613c) has a resin molded portion 603c formed at the center. One end of the signal electrode plate 613 (613a, 613b, 613c) is electrically connected to the gate electrode 222a, 222b and the temperature sensor electrode of the power semiconductor element of the IGBT 22 by solder joints 34a, 34b, 34c, respectively, and the other end Are electrically connected to the internal pads 63 (63a, 63b, 63c) of the signal terminals 630 (631, 632, 633) by solder joints 35a, 35b, 35c, respectively.

  The resin molding part 603c is made of PPS resin and is the center of the signal electrode plate 613 (613a, 613b, 613c) straddling the internal pad 63 (63a, 63b, 63c) of the signal terminal 630 (631, 632, 633) and the IGBT 22. It is formed by an insert mold method so as to connect the portions, and the bottom portion is a convex V-shape and is inclined. The resin molded portion 603c is provided by being integrally formed with the resin molded portion 603 formed at the central portion between the diode 21 and the IGBT 22 of the source electrode plate, and the resin molded portion 603c is formed by resin molding. The signal electrode plates 613 (613a, 613b, 613c) are positioned by being fixed to the recesses 52a, 52b of the case 5 by both ends 603a, 603b of the portion 603.

  FIG. 11 is a diagram for explaining a method for manufacturing the power module 102 according to the second embodiment, and is a perspective view corresponding to FIG. 4, but in the same manner as in the step of FIG. 3C, solder 32 a, 32 b, 32 c , 33a, 33b, and 34a, 34b, 34c, 35a, 35b, 35c, as shown in FIG. 11, the source electrode plate 611, the drain electrode plate 612, and the signal electrode plate 613 (613a, 613b, 613c), both ends 601a, 601b, and 603a, 603b of the resin molded portions 601 and 603 (603c) are positioned by being fitted into the recesses 51a, 51b, and 52a, 52b of the case 5, respectively. 21 and IGBT 22 source electrodes 211 and 221, screw electrodes 621, 22 are mounted on the internal pads 62a and 62b, and the solder is heated and melted, whereby the diode 21 and the IGBT 22 and the screwing electrode 621, the copper conductor layer 13 and the screwing electrode 622 on the ceramic substrate 10, and the IGBT 22 and the signal terminal 630 are obtained. (631, 632, 633) are electrically connected to form a circuit. The other configuration and manufacturing method of the power module 102 according to the second embodiment are the same as those of the power module 101 according to the first embodiment, and corresponding portions are denoted by the same reference numerals and description thereof is omitted.

  Thus, by using the signal electrode plate 613 (613a, 613b, 613c), it is possible not only to assemble the power module without performing wire bonding, but also when performing wire bonding, such as the gate electrode of the IGBT. If there is a void in the solder joint immediately below, there is a concern that the IGBT may crack due to the impact of the wire bond, so it was necessary to confirm that there was no void by X-ray inspection or the like. Since no impact is applied when connecting, void observation can be omitted.

  As described above, according to the power module 102 according to the second embodiment, not only the source electrode plate 611 and the drain electrode plate 612 as the main terminals, but also the signal electrode plate 613 (613a, 613a) connected to the IGBT 22 and the signal terminal 630. 613b, 613c), and the signal electrode plate 613 (613a, 613b, 613c) is also provided with a resin molded portion 603c having a convex shape and an inclined surface on the back side between the connecting portions. In addition to the effects of the above, the manufacture becomes easy and the reliability can be further improved.

Embodiment 3 FIG.
In Embodiment 3, the power module according to Embodiments 1 and 2 described above is applied to a power conversion device. Although the present application is not limited to a specific power conversion device, a case where the present application is applied to a three-phase inverter will be described below as a third embodiment.

  FIG. 12 is a block diagram showing a configuration of a power conversion system to which the power conversion device according to Embodiment 3 is applied.

  The power conversion system illustrated in FIG. 12 includes a power supply 100, a power conversion device 200, and a load 300. The power source 100 is a DC power source and supplies DC power to the power conversion device 200. The power source 100 can be composed of various types, for example, can be composed of a direct current system, a solar battery, a storage battery, or can be composed of a rectifier circuit or an AC / DC converter connected to the alternating current system. Also good. The power supply 100 may be configured by a DC / DC converter that converts DC power output from the DC system into predetermined power.

  The power conversion device 200 is a three-phase inverter connected between the power supply 100 and the load 300, converts the DC power supplied from the power supply 100 into AC power, and supplies the AC power to the load 300. As shown in FIG. 12, the power conversion device 200 converts a DC power into an AC power and outputs the main conversion circuit 201, and a control circuit 203 outputs a control signal for controlling the main conversion circuit 201 to the main conversion circuit 201. And.

  The load 300 is a three-phase electric motor that is driven by AC power supplied from the power conversion device 200. Note that the load 300 is not limited to a specific application, and is an electric motor mounted on various electric devices. For example, the load 300 is used as an electric motor for a hybrid vehicle or an electric vehicle, a railway vehicle, an elevator, or an air conditioner.

  Hereinafter, details of the power conversion device 200 will be described. The main conversion circuit 201 includes a switching element and a free wheel diode (not shown). When the switching element switches, the main conversion circuit 201 converts the DC power supplied from the power supply 100 into AC power and supplies the AC power to the load 300. Although there are various specific circuit configurations of the main conversion circuit 201, the main conversion circuit 201 according to the fourth embodiment is a two-level three-phase full-bridge circuit, and includes six switching elements and respective switching elements. It can be composed of six anti-parallel diodes. Each switching element and each free-wheeling diode of the main conversion circuit 201 are configured by a power module (described here as the power module 101) corresponding to any one of the above-described first and second embodiments. The six switching elements are connected in series for each of the two switching elements to constitute upper and lower arms, and each upper and lower arm constitutes each phase (U phase, V phase, W phase) of the full bridge circuit. The output terminals of the upper and lower arms, that is, the three output terminals of the main conversion circuit 201 are connected to the load 300.

  The main conversion circuit 201 includes a drive circuit (not shown) for driving each switching element. However, the drive circuit may be built in the power module 101, or a drive circuit may be provided separately from the power module 101. The structure provided may be sufficient. The drive circuit generates a drive signal for driving the switching element of the main conversion circuit 201 and supplies the drive signal to the control electrode of the switching element of the main conversion circuit 201. Specifically, in accordance with a control signal from the control circuit 203 described later, a drive signal for turning on the switching element and a drive signal for turning off the switching element are output to the control electrode of each switching element. When the switching element is kept on, the drive signal is a voltage signal (on signal) that is equal to or higher than the threshold voltage of the switching element. When the switching element is kept off, the drive signal is a voltage that is equal to or lower than the threshold voltage of the switching element. Signal (off signal).

  The control circuit 203 controls the switching element of the main conversion circuit 201 so that desired power is supplied to the load 300. Specifically, based on the power to be supplied to the load 300, the time (ON time) during which each switching element of the main converter circuit 201 is to be turned on is calculated. For example, the main conversion circuit 201 can be controlled by PWM control that modulates the ON time of the switching element in accordance with the voltage to be output. Then, a control command (control signal) is supplied to the drive circuit included in the main conversion circuit 201 so that an ON signal is output to the switching element that should be turned on at each time point and an OFF signal is output to the switching element that should be turned off. Is output. In accordance with this control signal, the drive circuit outputs an ON signal or an OFF signal as a drive signal to the control electrode of each switching element.

  In the power conversion device according to the third embodiment, since the power module according to the first and second embodiments is applied as the switching element and the free wheel diode of the main conversion circuit 201, the reliability can be improved.

  In the third embodiment, an example in which the present application is applied to a two-level three-phase inverter has been described. However, the present application is not limited to this and can be applied to various power conversion devices. In the third embodiment, a two-level power converter is used. However, a three-level or multi-level power converter may be used. When power is supplied to a single-phase load, the present application is applied to a single-phase inverter. It doesn't matter. Moreover, when supplying electric power to a DC load or the like, the present application can be applied to a DC / DC converter or an AC / DC converter.

  In addition, the power conversion device to which the present application is applied is not limited to the case where the load described above is an electric motor. For example, as a power supply device for an electric discharge machine or a laser machine, an induction heating cooker, or a non-contact power feeding system. It can also be used, and furthermore, it can also be used as a power conditioner such as a photovoltaic power generation system or a power storage system.

  Although this application describes various exemplary embodiments and examples, various features, aspects, and functions described in one or more embodiments may be applied to particular embodiments. The present invention is not limited to this, and can be applied to the embodiments alone or in various combinations. Accordingly, countless variations that are not illustrated are envisaged within the scope of the technology disclosed herein. For example, the case where at least one component is deformed, the case where the component is added or omitted, the case where the at least one component is extracted and combined with the component of another embodiment are included.

  7 encapsulating resin part, 10 ceramic substrate, 21 diode (power semiconductor element), 22 IGBT (power semiconductor element), 211, 221 source electrode, 601, 602, 603, 603c resin molding part, 611 source electrode plate, 612 drain Electrode plate, 613 Signal electrode plate, 101 power module, 200 power converter, 201 main converter circuit, 203 control circuit, 300 load.

Claims (9)

A semiconductor element disposed on a substrate;
A plate-like electrode plate having two or more connecting portions for connecting the semiconductor elements, the semiconductor element and an external terminal, or the substrate and the external terminal;
On the substrate surface side between the adjacent connection portions of the electrode plate, a convex and inclined resin molded portion;
A sealing resin portion for sealing the periphery of the connection portion;
A power module comprising:   2. The power module according to claim 1, wherein the resin molded portion has a V-shaped or U-shaped convex shape on the substrate surface side in a cross section perpendicular to the substrate.   The power module according to claim 1, wherein the resin molding portion is used for the electrode plate of the main electrode of the semiconductor element and the electrode plate of the signal electrode of the semiconductor element.   The power module according to any one of claims 1 to 3, wherein the resin molding portion is formed in a rod shape in a short direction with respect to the substrate.   The power module according to claim 4, wherein the resin molding portion connects a plurality of the electrode plates.   The power module according to claim 4, wherein the resin molding portion is fixed to the substrate.   The power module according to claim 4, further comprising a case fixed to the substrate and surrounding the sealing resin portion, wherein the resin molding portion is fixed to the case. A main conversion circuit that has the power module according to any one of claims 1 to 7, converts input power, and outputs the converted power.
A power conversion device comprising: a control circuit that outputs a control signal for controlling the main conversion circuit to the main conversion circuit. Mounting a semiconductor element on a substrate;
Forming a convex and inclined resin molded portion on the substrate surface side between the connecting portions of the plate-like electrode plates, and connecting the electrode plates to the semiconductor element;
Forming a sealing resin portion that seals a connection portion between the semiconductor element and the electrode plate.

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