Semiconductor device and method for manufacturing semiconductor device

Abstract

The invention provides a semiconductor device and a method of manufacturing the semiconductor device, the semiconductor device includes: a switching element having a first main electrode on one surface; a connection conductor connected to the first main electrode of the switching element; a sealing part that seals a space between the switching element and the connection conductor; and an insulating layer disposed between at least a portion of the switching element and the connection conductor so as to overlap the sealing portion.

Description

Technical Field

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

[0002] Patent Document 1 describes that "a semiconductor module 100 including a semiconductor assembly 110 having a plurality of semiconductor chips 30 can be configured as a converter as a whole, and power devices such as an IPM (Intelligent Power Module) including a control circuit" (paragraph 0031), "As an example, the PCB 40 is electrically connected to the semiconductor chip 30 by a bonding wire 55" (paragraph 0032), "Nickel plating can be performed on the external connection portion 50. By connecting a copper bus bar to the external connection portion 50, a large current can be applied to each main terminal 52 of the semiconductor assembly 110" (paragraph 0033), and "The semiconductor assembly 110 may have a metal wiring board 70 that electrically connects the semiconductor chip 30 and the main terminal 52. Instead of the metal wiring board 70, a conductive member such as a wire and / or a tape may be used to electrically connect the semiconductor chip 30 and the main terminal 52" (paragraph 0035).

[0003] Patent Document 2 describes that "two semiconductor elements 3 are electrically connected by a wiring member W1. One semiconductor element 3 is electrically connected to a second circuit layer 24 via a wiring member W2. The second circuit layer 24 is electrically connected to an external terminal 27 described later via a wiring member W3. The other semiconductor element 3 is electrically connected to a third circuit layer 25 via a wiring member W4. The third circuit layer 25 is electrically connected to another external terminal 27 via a wiring member W5" (paragraph 0023), "It should be noted that each of the above wiring members uses a conductor wire. The material of the conductor wire can be any one of gold, copper, aluminum, gold alloy, copper alloy, aluminum alloy, or a combination of these. In addition, as the wiring member, a member other than the conductor wire can also be used. For example, a tape can be used as the wiring member" (paragraph 0024), "The insulating circuit board 2 and the semiconductor element 3 are covered by a housing 11 that surrounds the periphery. The housing 11 is composed of an annular wall portion 12 that surrounds the outer peripheral side of the insulating circuit board 2 and a cover portion 13 that covers the upper side of the insulating circuit board 2 and the semiconductor element 3. For example, the housing 11 is formed of a synthetic resin" (paragraph 0025).

[0004] Prior Art Documents Patent Documents Patent Document 1: Japanese Patent Application Laid-Open No. 2021-2610 Patent Document 2: International Publication No. 2020 / 121680 Summary of the Invention

[0005] Technical Problem Thinning a semiconductor module including a switching element.

[0006] Technical solution In a first aspect of the present invention, a semiconductor device is provided, which includes: a switching element having a first main electrode on one surface; a connection conductor connected to the first main electrode of the switching element; a sealing portion sealing a space between the switching element and the connection conductor; and an insulating layer disposed overlapping the sealing portion between at least a part of the switching element and the connection conductor.

[0007] In the above semiconductor device, the resistivity of the insulating layer may be higher than the resistivity of the sealing material of the sealing portion.

[0008] In any of the above semiconductor devices, the insulating layer may be laminated on the surface of the connection conductor closer to the switching element.

[0009] In any of the above semiconductor devices, the insulating layer may face a region including at least a part of the outer edge portion of the switching element up to the outer edge portion of the conductor exposed on the surface of the switching element closer to the connection conductor, and is disposed on the surface of the connection conductor closer to the switching element.

[0010] In any of the above semiconductor devices, the region of the connection conductor connected to the first main electrode may protrude toward the first main electrode with respect to the region where the insulating layer is disposed.

[0011] In any of the above semiconductor devices, the connection conductor may have a groove between the region connected to the first main electrode and the region where the insulating layer is disposed.

[0012] In any of the above semiconductor devices, the insulating layer may be laminated on the surface of the switching element closer to the connection conductor.

[0013] In any of the above semiconductor devices, the connection conductor may have a plurality of bumps in contact with the first main electrode.

[0014] Any of the above semiconductor devices may include a mounting substrate having the connection conductor on a mounting surface for mounting the switching element, and having a first main electrode plate connected to the connection conductor in a region of the mounting surface where the switching element is not disposed.

[0015] Any of the above semiconductor devices may include a second main electrode plate connected to the second main electrode of the switching element, the mounting substrate may have a control electrode plate connected to the control electrode of the switching element, and the first main electrode plate, the second main electrode plate, and the control electrode plate may be exposed on one surface of the semiconductor device.

[0016] In any of the above semiconductor devices, the mounting substrate may have a heat conducting plate formed on a surface opposite to the mounting surface.

[0017] In any of the above semiconductor devices, the switching element may be a power MOSFET, an IGBT, or a SiC semiconductor element.

[0018] In a second aspect of the present invention, there is provided a method of manufacturing a semiconductor device, including: preparing a switching element having a first main electrode on one surface; disposing an insulating layer at a position between at least a part of the switching element and a connection conductor to be connected to the first main electrode; connecting the connection conductor to the first main electrode of the switching element; and sealing a space between the switching element and the connection conductor with the sealing material.

[0019] In the above manufacturing method, the step of disposing the insulating layer may include a step of laminating the insulating layer on a surface layer of the connection conductor on the side of the switching element.

[0020] In any of the above manufacturing methods, the step of laminating the insulating layer on a surface layer of the connection conductor on the side of the switching element may include a step of mounting an insulating sheet that becomes the insulating layer on a surface of the connection conductor on the side of the switching element.

[0021] In any of the above manufacturing methods, the step of laminating the insulating layer on a surface layer of the connection conductor on the side of the switching element may include a step of coating an insulating material that becomes the insulating layer on a surface of the connection conductor on the side of the switching element.

[0022] In any of the above manufacturing methods, the connection conductor may have a step between a region to be connected to the first main electrode and a region where the insulating layer is to be disposed, and the step prevents the insulating material from spreading to the region to be connected to the first main electrode.

[0023] In any of the above manufacturing methods, the connection conductor may have a groove between a region to be connected to the first main electrode and a region where the insulating layer is to be disposed, and the groove prevents the insulating material from spreading to the region to be connected to the first main electrode.

[0024] In any of the above manufacturing methods, the step of coating the insulating material may include: coating a part of the insulating material that becomes the insulating layer on the surface of the connection conductor on the side of the switching element, and forming a boundary wall made of the insulating material at the boundary between the region of the connection conductor to be connected to the first main electrode and the region where the insulating layer is to be disposed; and coating another part of the insulating material on the side of the region where the insulating layer is to be disposed with respect to the boundary wall to form the insulating layer.

[0025] It should be noted that the above description of the invention does not list all the features of the present invention. In addition, sub-combinations of these feature groups can also form inventions. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is a perspective view of the switching element 10 of the present embodiment.

[0027] Figure 2 is a cross-section of the semiconductor device 200 of the reference example.

[0028] Figure 3 is a cross-section of the semiconductor device 200 of the present embodiment.

[0029] Figure 4 is a cross-section of the semiconductor device 200 of the first modification of the present embodiment.

[0030] Figure 5 is a perspective view of the semiconductor device 200 of the present embodiment.

[0031] Figure 6 shows a manufacturing method of the semiconductor device 200 of the present embodiment.

[0032] Figure 7 is a perspective view of a structure obtained by bonding the second main electrode plate 230 to the switching element 10 of the present embodiment.

[0033] Figure 8 is a perspective view of the mounting substrate 210 of the present embodiment.

[0034] Figure 9 shows a state in which the insulating layer 280 is disposed on the mounting substrate 210 of the present embodiment.

[0035] Figure 10 is a perspective view of a structure obtained by bonding the switching element 10 bonded with the second main electrode plate 230 to the mounting substrate 210 of the present embodiment.

[0036] Figure 11 is a perspective view of a structure obtained by bonding the first main electrode plate 220, the control electrode plate 240, and the sub-electrode plate 250 to the mounting substrate 210.

[0037] Figure 12 Shows the state in which the insulating layer 280 is disposed on the mounting substrate 210 in the second modification of the present embodiment.

[0038] Figure 13 Is a cross-section of the semiconductor device 200 in the third modification of the present embodiment.

[0039] Figure 14 Shows the state in which the insulating layer 280 is disposed on the mounting substrate 210 in the fourth modification of the present embodiment.

[0040] Figure 15 Shows the state in which the boundary wall 290 is disposed on the mounting substrate 210 in the fifth modification of the present embodiment.

[0041] Symbol description 10 Switch element 12 Chip substrate 14 Metal film 16 Insulating film 20 Connecting conductor 22 Conductor pattern 24 Post 100 First main electrode 110 Control electrode 120 Second main electrode 130 Sensing electrode 200 Semiconductor device 210 Mounting substrate 220 First main electrode plate 230 Second main electrode plate 240 Control electrode plate 250 Sub-electrode plate 260 Sealing portion 270 Heat conducting plate 280 Insulating layer 285 Groove 290 Boundary wall 500 Insulating substrate 510 First main electrode wiring 513 First main electrode contact 515 Wiring 517 First main electrode plate contact 520 Control wiring 523 Control electrode contact 525 Wiring 527 Control electrode plate contact 530 Sub-wiring 535 Wiring 537 Sub - electrode plate contact Detailed implementation manner

[0042] Hereinafter, the present invention will be described by way of embodiments of the invention. However, the following embodiments do not limit the invention related to the claims. In addition, not all combinations of the features described in the embodiments are necessarily required for the technical solution of the invention.

[0043] Figure 1 is a perspective view of the switching element 10 of the present embodiment. The switching element 10 is a semiconductor switching element such as a MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The switching element 10 can be a power MOSFET with a vertical structure. The switching element 10 can be a Si semiconductor element such as a Si - MOSFET, a SiC semiconductor element such as a SiC - MOSFET that can switch more quickly, or a wide - bandgap semiconductor such as GaN, diamond, gallium nitride - based materials, gallium oxide - based materials, AlN, AlGaN, or ZnO can also be used. Instead, the switching element 10 can be a semiconductor switching element such as an IGBT (Insulated Gate Bipolar Transistor), or a SiC - IGBT. In addition, the switching element 10 can be a HEMT (High Electron Mobility Transistor).

[0044] The switching element 10 can be a semiconductor chip having a first main electrode 100 and a control electrode 110 on one surface (the upper surface in the figure), and a second main electrode 120 on the opposite surface. In the example of this figure, the switching element 10 also has a sense electrode 130 on the upper surface in the figure. When the switching element 10 is a MOSFET, the switching element 10 has a source and a drain as the first main electrode 100 and the second main electrode 120, a gate as the control electrode 110, and a sense source as the sense electrode 130. When the switching element 10 is an IGBT, the switching element 10 has an emitter and a collector as the first main electrode 100 and the second main electrode 120, a gate as the control electrode 110, and a sense emitter as the sense electrode 130. In the present embodiment, for the sake of convenience of description, the case where the switching element 10 is a MOSFET is shown.

[0045] It should be noted that the names "first main electrode" and "second main electrode" are for differentiating the two main electrodes of the switching element 10 and are marked for convenience of explanation. Therefore, the switching element 10 can be regarded as having a symbol 100 as the second main electrode and a control electrode 110 on one surface, and having a 120 as the first main electrode on the opposite surface. In addition, the switching element 10 used in the semiconductor device 200 shown below can also be configured such that the second main electrode 120 is not provided on the surface opposite to the first main electrode 100, or the second main electrode 120 can be provided on the surface on the side of the first main electrode 100.

[0046] Figure 2 is a cross-section of the semiconductor device 200 of the reference example. For a semiconductor module using Figure 1 a switching element such as the switching element 10 shown, a structure is generally adopted in which one surface of the switching element (for example, the surface on the side of the second main electrode 120) is bonded to a wiring pattern on a substrate, and each electrode (for example, the first main electrode 100, the control electrode 110, and the sensing electrode 130) on the other surface is electrically connected to other wiring patterns by wire bonding. Such a semiconductor module is realized as a module in which the substrate on which the switching element is mounted, each bonding wire, and each metal plate connected to the positive terminal, the negative terminal, and the output terminal are resin-sealed as a single body.

[0047] In contrast, in the semiconductor device 200 of the reference example, by exposing one surface of the switching element 10 (for example, the surface on the side of the second main electrode 120) directly or via the second main electrode plate 230 on the surface of the semiconductor device 200, it is possible to bond to a wiring pattern on a substrate outside the semiconductor device 200, and on the other surface side of the switching element 10, each electrode (for example, the first main electrode 100, the control electrode 110, and the sensing electrode 130) is directly connected to a connection conductor such as a wiring pattern on a substrate provided inside the semiconductor device 200. Such a connection conductor electrically connects each electrode on the other surface side of the switching element 10 to an external electrode such as an electrode plate exposed outside the semiconductor device 200. Instead, the semiconductor device 200 can also adopt a structure in which the surfaces on the side of the first main electrode, 100 control electrode 110, and sensing electrode 130 are exposed on the surface of the semiconductor device 200 and the surface on the side of the second main electrode 120 is directly connected to the connection conductor. With such a structure, it is not necessary to connect each electrode of the switching element 10 by wire bonding inside the semiconductor device 200, so that the semiconductor device 200 can be thinned. In addition, by using such a semiconductor device 200, it is possible to reduce the thickness of the semiconductor module or make it compact.

[0048] The semiconductor device 200 of the reference example includes a switching element 10, a mounting substrate 210, a second main electrode plate 230, and a sealing portion 260. In this figure, the switching element 10 is arranged such that the surface on the side of the first main electrode 100 etc. faces downward in the figure and the surface on the side of the second main electrode 120 faces upward in the figure. The switching element 10 has an element structure in cross-section, and this element structure includes a metal film 14, an interlayer insulating film 16, etc. on the chip substrate 12 (lower side in the figure). It should be noted that in this figure, the part of the element structure that should be formed on the chip substrate 12 is shown centered on the part of interest in this application, and the illustration and description of the more detailed structure are omitted.

[0049] The metal film 14 is exposed on one surface (the lower surface in the figure) of the switching element 10 and functions as an electrode of the switching element 10. In the example of this figure, the metal film 14 can be Figure 1 the first main electrode 100. Instead, the metal film 14 can also be the control electrode 110, or can also be the sensing electrode 130. Additionally, the metal film 14 can also be Figure 1 the second main electrode 120.

[0050] The interlayer insulating film 16 is an insulating film such as a silicon oxide film, a silicon nitride film, or formed of other substances that is integrally formed with the switching element 10 using semiconductor processes during the manufacturing process of the switching element 10. The interlayer insulating film 16 can be integrally formed with the switching element 10 before the singulation of the switching element 10 in the semiconductor process for manufacturing the switching element 10.

[0051] The mounting substrate 210 mounts the switching element 10 on the mounting surface (the upper surface in the figure). The mounting substrate 210 has an insulating substrate 500 and connection conductors 20 formed on the mounting surface of the insulating substrate 500 for the switching element 10. The connection conductors 20 are connected to the first main electrode 100 of the switching element 10. The connection conductors 20 can include a conductor pattern 22 and one or more posts 24. The conductor pattern 22 can be formed of a conductive metal film or metal plate such as copper on the insulating substrate 500. As an example, the conductor pattern 22 is a wiring pattern for connecting an external electrode arranged at a position not overlapping with the chip substrate 12 when looking down at the semiconductor device 200 and the switching element 10. One or more posts 24 are arranged in the region of the conductor pattern 22 facing the metal film 14, and connect the conductor pattern 22 and the metal film 14 by contacting the metal film 14. The posts 24 are formed of a conductive metal. In the example of this figure, the posts 24 are cylindrical posts etc. In the example of this figure, the posts 24 are used, but any shaped protrusions (bumps) can be used instead of being limited to posts.

[0052] The mounting substrate 210 may have a heat conducting plate 270 formed on a surface of the insulating substrate 500 opposite to the mounting surface of the switching element 10. The heat conducting plate 270 may be a heat conducting member having a higher heat conductivity than that of the insulating substrate 500 such as a copper plate.

[0053] The second main electrode plate 230 is electrically connected to the second main electrode 120 of the switching element 10. The sealing portion 260 seals the space between the switching element 10 and the connection conductor 20. For example, a resin material such as epoxy or silicone may be injected between the switching element 10 and the connection conductor 20 and cured to form the sealing portion 260.

[0054] With the configuration shown above, the semiconductor device 200 can be thinned. However, depending on the application object of the semiconductor module using the semiconductor device 200, a high voltage of several hundred V or one thousand several hundred V etc. may be applied between the main electrodes of the switching element 10. Here, the surface of the switching element 10 on the side of the second main electrode plate 230 and the outer edge portion of the switching element 10 (i.e., the outer edge portion of the chip substrate 12) are at substantially the same potential as the second main electrode 120, and the connection conductor 20 and the first main electrode 100 are at substantially the same potential. As shown by the arrows in the figure, the insulation between the outer edge portion of the switching element 10 (more specifically, the edge on the side of the connection conductor 20 in the side surface of the chip substrate 12) and the connection conductor 20 etc. becomes a problem. For example, when the distance between the switching element 10 and the conductor pattern 22 is set to several tens of μm to one hundred and several tens of μm etc. by thinning the semiconductor device 200, the insulation distance may not be sufficient only by separating the outer edge portion of the chip substrate 12 and the conductor pattern 22 by the sealing portion 260.

[0055] Figure 3 is a cross section of the semiconductor device 200 of the present embodiment. Since the semiconductor device 200 shown in this figure Figure 2 adds an insulating layer 280 to the semiconductor device 200 of the reference example shown, the description is omitted except for the following differences.

[0056] The semiconductor device 200 of the present embodiment includes an insulating layer 280, which is disposed overlapping the sealing portion 260 between at least a part of the switching element 10 and the connection conductor 20. The insulating layer 280 may be disposed between the outer edge portion of the switching element 10 and the connection conductor 20 over the entire outer edge portion of the switching element 10, or may be disposed between the outer edge portion of the switching element 10 and the connection conductor 20 at least in a part of the outer edge portion of the switching element 10. The insulating layer 280 may also be disposed between at least a part (for example, a part having the same potential as the second main electrode 120) of the surface of the switching element 10 on the side of the first main electrode 100 where the potential difference from the connection conductor 20 exceeds a predetermined limit voltage and the connection conductor 20. In the example of this figure, the insulating layer 280 is laminated on the surface of the connection conductor 20 on the side of the switching element 10.

[0057] The insulating layer 280 can be formed of a material having a resistivity higher than that of the sealing material of the sealing portion 260. As an example, the insulating layer 280 can be polyimide, polyester, liquid crystal polymer, etc., or a layer, film, sheet (such as an insulating adhesive sheet) based on at least one of them. The insulating layer 280 can have a thickness of 1 / 2 or less, or 1 / 4 or less, of the distance between the outer edge portion of the switching element 10 and the connection conductor 20. By reducing the thickness of the insulating layer 280, the sealing material can easily flow between the switching element 10 and the connection conductor 20. The insulating layer 280 can have a thickness of 1 / 20 or more, 1 / 10 or more, or 1 / 8 or more, of the distance between the outer edge portion of the switching element 10 and the connection conductor 20. By using a material with a high resistivity as the insulating layer 280, sufficient insulation can be obtained even if the thickness of the insulating layer 280 is relatively small.

[0058] The range where the insulating layer 280 is provided can be determined according to the structure of the semiconductor device 200 and the required withstand voltage. For the range where the insulating layer 280 is provided, it can be determined based on the condition that the sum of the distance between the outer edge portion of the switching element 10 and the insulating layer 280 and the creepage distance from the position directly below the outer edge portion of the switching element 10 in the insulating layer 280 to the conductor pattern 22 along the surface of the insulating layer 280 is a sufficient insulation distance with respect to the required withstand voltage. In the example of this figure, such a creepage distance can be the length of the shortest path from the position directly below the outer edge portion of the switching element 10 in the sealing portion 260 to the exposed portion of the conductor pattern 22 exposed from the insulating layer 280 (in the example of this figure, the upper surface portion of the conductor pattern 22 exposed from the insulating layer 280 on the right end side of the insulating layer 280 and the side surface portion of the conductor pattern 22 exposed from the insulating layer 280 on the left end side of the insulating layer 280) along the surface of the sealing portion 260. In addition, when the length of the path from the position directly below the outer edge portion of the switching element 10 in the sealing portion 260 to the exposed portion of the conductor pattern 22 exposed from the insulating layer 280 at the right end conductor pattern 22 in the figure of the sealing portion 260 is relatively short, when setting the length of this path as the creepage distance, sufficient insulation distance is sought.

[0059] In addition, the insulating layer 280 can be disposed to face a region including the outer edge portion of the conductor (such as the metal film 14) exposed from at least a part of the outer edge portion of the switching element 10 to the surface on the side of the connection conductor 20 of the switching element 10. In the example of this figure, since the metal film 14 is connected to the connection conductor 20, the metal film 14 and the connection conductor 20 are substantially at the same potential. Therefore, the insulating layer 280 may not be disposed between the metal film 14 and the conductor pattern 22.

[0060] Further, in the case where the switching element 10 is a vertical semiconductor element such as a power MOSFET or an IGBT, a protection ring that surrounds the element structure provided on the surface on the connection conductor 20 side is provided near the outer edge portion of the surface of the chip substrate 12 on the connection conductor 20 side. On the surface of the switching element 10 on the connection conductor 20 side, the region outside the protection ring can be substantially at the same potential as the opposite surface in the switching element 10. Therefore, the insulating layer 280 can be disposed to face a region including at least a part of the outer edge portion of the switching element 10 to the protection ring of the switching element 10. It should be noted that the insulating layer 280 only needs to be disposed in a minimum required range that can ensure insulation, and as long as the required insulation can be ensured, it can also be disposed in a range smaller than the range shown above.

[0061] According to the semiconductor device 200 shown above, while thinning the semiconductor device 200, the insulation between the switching element 10 and the connection conductor 20 can be sufficiently ensured.

[0062] Figure 4 is a cross-section of the semiconductor device 200 according to the first modification of the present embodiment. Since the semiconductor device 200 shown in this figure is Figure 3 a modification of the semiconductor device 200 shown, the description is omitted except for the following differences.

[0063] Same as Figure 3 the semiconductor device 200 shown, the semiconductor device 200 of this modification includes an insulating layer 280 that is disposed to overlap with the sealing portion 260 between the outer edge portion of the switching element 10 and the connection conductor 20. The insulating layer 280 can be disposed between the outer edge portion and the connection conductor 20 over the entire outer edge portion of the switching element 10, or can be disposed between the outer edge portion and the connection conductor 20 over at least a part of the outer edge portion of the switching element 10. In this modification, the insulating layer 280 is laminated on the surface of the switching element 10 on the connection conductor 20 side.

[0064] In this modification, the insulating layer 280 covers the entire thickness direction of the side surface of the switching element 10 in order to ensure the insulation distance between the outer edge portion of the switching element 10 and the connection conductor 20. Instead, as long as a sufficient insulation distance can be ensured, the insulating layer 280 can also cover at least a part of the range on the connection conductor 20 side in the thickness direction of the switching element 10 only on the side surface of the switching element 10. Same as Figure 3 the semiconductor device 200, the thickness of the insulating layer 280 and the range where the insulating layer 280 is provided can be determined according to the structure of the semiconductor device 200 and the required withstand voltage.

[0065] Figure 5 This is a perspective view of the semiconductor device 200 of the present embodiment. The semiconductor device 200 of the present embodiment has a structure in which electrode plates each electrically connected to an electrode of the switching element 10 are exposed on one surface of the plate-shaped semiconductor device 200. In the present embodiment, the semiconductor device 200 includes a mounting substrate 210, a first main electrode plate 220, a second main electrode plate 230, a control electrode plate 240, a sub-electrode plate 250, and a sealing portion 260.

[0066] The mounting substrate 210 mounts the switching element 10 on the mounting surface (the upper surface in the figure). The first main electrode plate 220 is electrically connected to the first main electrode 100 of the switching element 10. The second main electrode plate 230 is electrically connected to the second main electrode 120 of the switching element 10. The control electrode plate 240 is electrically connected to the control electrode 110 of the switching element 10. The sub-electrode plate 250 is electrically connected to the first main electrode 100 of the switching element 10. Here, the first main electrode plate 220, the second main electrode plate 230, the control electrode plate 240, and the sub-electrode plate 250 are exposed on the surface of the semiconductor device 200 opposite to the side of the mounting substrate 210 (the side of the mounting surface of the switching element 10 of the mounting substrate 210). The sealing portion 260 exposes the first main electrode plate 220, the second main electrode plate 230, the control electrode plate 240, and the sub-electrode plate 250, and covers the mounting surface of the switching element 10 on the mounting substrate 210.

[0067] By using the semiconductor device 200 of the present embodiment to bond the electrode plates on one surface of the semiconductor device 200 to the wiring pattern on the substrate instead of modularizing the switching element 10 as described above, all the required electrodes in the switching element 10 can be electrically connected to the wiring on the substrate without wire bonding.

[0068] It should be noted that the semiconductor device 200 may also have an electrode plate electrically connected to the sensing electrode 130 on the same surface as the first main electrode plate 220 and the like. In addition, both the first main electrode plate 220 and the sub-electrode plate 250 are electrically connected to the first main electrode 100 of the switching element 10, but the first main electrode plate 220 has a large area and is used for flowing a large current, and the sub-electrode plate 250 is paired with the control electrode plate 240 for controlling the switching element 10. In other embodiments, the semiconductor device 200 may not include the sub-electrode plate 250, and in this case, the first main electrode plate 220 is also used for controlling the switching element 10.

[0069] Figure 6 Shows the manufacturing method of the semiconductor device 200 of the present embodiment. Hereinafter, with reference to the configuration showing the intermediate stage of manufacturing the semiconductor device 200 Figures 7 - 11A method for manufacturing a semiconductor device 200 will be described. In S300 (Step 300), a switching element 10 is prepared, which has a first main electrode 100 and a control electrode 110 on one surface and a second main electrode 120 on the opposite surface.

[0070] In S310, a second main electrode plate 230 is joined to the surface of the switching element 10 on the side of the second main electrode 120. Figure 7 It is a perspective view of a structure formed by joining a second main electrode plate 230 to the switching element 10 of the present embodiment. The second main electrode plate 230 is a conductive plate such as a copper plate. The second main electrode plate 230 can be joined to the second main electrode 120 using a sintering agent of nano silver, and the second main electrode plate 230 can also be joined to the second main electrode 120 by direct gold-gold bonding. Thus, the second main electrode plate 230 is electrically connected to the second main electrode 120 of the switching element 10. In addition to the above, the second main electrode plate 230 can also be joined by a solder material or by direct copper-copper bonding. Further, a plurality of bumps arranged regularly or irregularly on the second main electrode plate 230 can be joined to the second main electrode of the switching element 10.

[0071] In S320, a mounting substrate 210 is fabricated. Figure 8 It is a perspective view of the mounting substrate 210 of the present embodiment. In this process, a mounting substrate 210 is fabricated, which has a wiring pattern of a first main electrode wiring 510, a control wiring 520, and a sub-wiring 530 on the mounting surface of an insulating substrate 500 such as Si, silicon nitride, or aluminum nitride where the switching element 10 is to be mounted. The insulating substrate 500 can also be made of a ceramic material including the above.

[0072] The first main electrode wiring 510 is formed of a conductive metal film or metal plate such as copper. The first main electrode wiring 510 is Figures 2 - 4 an example of the connection conductor 20 in Figures 2 - 4 . The first main electrode wiring 510 includes a first main electrode contact 513, a wiring 515, and a first main electrode plate contact 517. The first main electrode contact 513 is a part connected to the first main electrode 100 of the switching element 10. The wiring 515 corresponds to the conductor pattern 22 in Figures 2 - 4 and electrically connects the first main electrode contact 513 and the first main electrode plate contact 517. The first main electrode plate contact 517 is a part connected to the first main electrode plate 220.

[0073] Similarly to the first main electrode wiring 510, the control wiring 520 is formed of a conductive metal film or metal plate such as copper. The control wiring 520 includes a control electrode contact 523, a wiring 525, and a control electrode plate contact 527. The control electrode contact 523 is a part connected to the control electrode 110 of the switching element 10. The wiring 525 electrically connects between the control electrode contact 523 and the control electrode plate contact 527. The control electrode plate contact 527 is a part connected to the control electrode plate 240. The control wiring 520 can also be regarded as Figures 2 - 4 the connection conductor 20 in

[0074] Similarly to the first main electrode wiring 510, the sub-wiring 530 is formed of a conductive metal film or metal plate such as copper. The sub-wiring 530 includes a first main electrode contact 513, a wiring 535, and a sub-electrode plate contact 537. The first main electrode contact 513 is shared with the first main electrode wiring 510. The sub-wiring 530 can utilize a part of the first main electrode contact 513 used by the first main electrode wiring 510. The wiring 535 electrically connects between the first main electrode contact 513 and the sub-electrode plate contact 537. The wiring width of the wiring 535 can also be smaller than the wiring width of the wiring 515. The sub-electrode plate contact 537 is a part connected to the sub-electrode plate 250. The sub-wiring 530 can also be regarded as Figures 2 - 4 the connection conductor 20 in

[0075] Here, regions where the first main electrode contact 513 and the first main electrode plate contact 517 of the first main electrode wiring 510, the control electrode contact 523 and the control electrode plate contact 527 of the control wiring 520, and the sub-electrode plate contact 537 of the sub-wiring 530 are joined to the respective electrodes of the switching element 10, or the respective electrode plates such as the first main electrode plate 220, the second main electrode plate 230, the control electrode plate 240, and the sub-electrode plate 250 can each have a plurality of bumps arranged regularly or irregularly. Figures 2 - 4 The column 24 shown is an example of such a bump. These plurality of bumps can be, for example, bumps of a conductive metal such as gold. These plurality of bumps can be formed, for example, by disposing a bump precursor of a conductive metal in each region by using transfer or the like, and firing and curing the bump precursor.

[0076] In S325, at the whole or at least a part of the outer edge portion of the switching element 10, an insulating layer 280 is disposed at a position between the outer edge portion and the first main electrode wiring 510 etc. ( Figures 2 - 4 the connection conductor 20 in Figure 9The state in which the insulating layer 280 is disposed on the mounting substrate 210 of the present embodiment is shown. In the example of this figure, the insulating layer 280 is disposed by laminating the insulating layer 280 on the surface layer closer to the switch element 10 side in the first main electrode wiring 510 or the like.

[0077] In the example of this figure, the insulating layer 280 is disposed in a region surrounding the first main electrode contact 513 where a plurality of posts 24 are formed on the first main electrode wiring 510. In the example of this figure, the insulating layer 280 is disposed by mounting or pasting an insulating sheet that becomes the insulating layer 280 on the surface closer to the switch element 10 side in the first main electrode wiring 510. In this process, an insulating sheet obtained by cutting a strip-shaped insulating sheet into a required length can be mounted along each side of the outer periphery of the first main electrode contact 513, so as to dispose the region surrounding the first main electrode contact 513. Instead, an insulating sheet having a shape surrounding the periphery of the first main electrode contact 513 can be fabricated and mounted on the connection conductor 20. Here, for positions on the outer edge portion of the switch element 10 where there is no facing position with the connection conductor 20 such as the first main electrode wiring 510, the insulating layer 280 may not be disposed as long as sufficient insulation can be obtained.

[0078] It should be noted that in addition to the first main electrode 100 being provided, electrodes such as the control electrode 110 are also provided on the surface of the switch element 10 closer to the mounting substrate 210 side. In addition to being disposed in the region surrounding the first main electrode contact 513, the insulating layer 280 can also be disposed in a region that collectively surrounds the periphery of the control electrode contact 523 in the control wiring 520.

[0079] In S330, the switch element 10 is mounted on the mounting surface of the mounting substrate 210 where each wiring pattern is formed. Figure 10 It is a perspective view of a structure in which the switch element 10 joined with the second main electrode plate 230 is joined to the mounting substrate 210 of the present embodiment. As Figure 7 shown, the switch element 10 joined with the second main electrode plate 230 is joined to the mounting surface of the mounting substrate 210 with the upper side surface of the Figure 7 switch element 10 facing downward. Thereby, the first main electrode 100 of the switch element 10 is joined to the first main electrode contact 513 of the first main electrode wiring 510 and the sub-wiring 530, and the control electrode 110 of the switch element 10 is joined to the control electrode contact 523 of the control wiring 520. This joining method can be the same as the joining method of the second main electrode plate 230 to the second main electrode 120. Thereby, a state is formed in which the insulating layer 280 is disposed between the outer edge portion of the switch element 10 and the connection conductor 20.

[0080] In S340, each electrode plate is joined to each wiring of the mounting substrate 210. Figure 11This is a perspective view of a structure in which a first main electrode plate 220, a control electrode plate 240, and a sub - electrode plate 250 are joined to a mounting substrate 210 of the present embodiment. As Figure 11 shown, the first main electrode plate contact 517 of the first main electrode wiring 510, the control electrode plate contact 527 of the control wiring 520, and the sub - electrode plate contact 537 of the sub - wiring 530 are located in a region of the mounting surface of the mounting substrate 210 where the switching element 10 is to be mounted and where the switching element 10 is not arranged. In this process, the first main electrode plate 220, the control electrode plate 240, and the sub - electrode plate 250 are respectively joined to such first main electrode plate contact 517, control electrode plate contact 527, and sub - electrode plate contact 537. This joining method can be the same as the joining method of the second main electrode plate 230 to the second main electrode 120.

[0081] As a result, the first main electrode plate 220, the control electrode plate 240, and the sub - electrode plate 250 are located in a region of the mounting surface of the switching element 10 where the switching element 10 is not arranged, and are electrically connected to the first main electrode wiring 510, the control wiring 520, and the sub - wiring 530 respectively. In this way, a mounting substrate 210 is produced, which has an insulating substrate 500, and the first main electrode wiring 510, the first main electrode plate 220, the control wiring 520, the control electrode plate 240, the sub - wiring 530, and the sub - electrode plate 250 formed on the insulating substrate 500.

[0082] Here, in the semiconductor device 200 of the present embodiment, on the mounting surface of the switching element 10 in the mounting substrate 210, the switching element 10 is arranged between the first main electrode plate 220 and the control electrode plate 240. The sub - electrode plate 250 can be arranged on the same side as the control electrode plate 240 with respect to the switching element 10. Thus, the semiconductor device 200 can adopt a configuration capable of connecting the control wiring to the control electrode plate 240 and the sub - electrode plate 250 located at one end of the semiconductor device 200.

[0083] In S350, a sealing portion 260 is formed by sealing the mounting surface of the mounting substrate 210 with a sealing material so as to expose each electrode plate, thereby obtaining Figure 5 the semiconductor device 200 shown. Here, the sealing portion 260 covers the mounting surface of the switching element 10 in the mounting substrate 210 and the surface of the switching element 10 on the side closer to the mounting substrate 210, and exposes the first main electrode plate 220, the second main electrode plate 230, the control electrode plate 240, and the sub - electrode plate 250 on the terminal surface of the semiconductor device 200 ( Figure 2The upper surface is exposed. This sealing can be a resin sealing based on a molding material. By sealing the mounting surface of the mounting substrate 210, the space between the switching element 10 and the connection conductor 20 can be sealed with a sealing material. Thus, the semiconductor device 200 has a structure in which a sealing portion 260 and an insulating layer 280 are overlapped and arranged between the outer edge portion of the switching element 10 and the conductor pattern 22 in the first main electrode wiring 510 ( Figures 2 - 4 ).

[0084] In this process, after sealing in a manner that covers the mounting surface of the switching element 10 in the mounting substrate 210 and the surface of the switching element 10 on the side closer to the mounting substrate 210, the terminal surface of the semiconductor device 200 can be ground to cut off the excess sealing material to expose each electrode plate. In other embodiments, the sealing process can be omitted, and the semiconductor device 200 may not have the sealing portion 260. It should be noted that after this process, an antioxidant film can also be formed by plating the exposed surfaces of each electrode plate with Sn or the like.

[0085] According to the manufacturing method shown above, a semiconductor device 200 in which each terminal electrically connected to each electrode of the switching element 10 is exposed on one surface can be manufactured. It should be noted that in the manufacturing method shown above, in S310, the second main electrode plate 230 is joined to the surface of the switching element 10 on the side closer to the second main electrode 120, but this process can also be omitted. In this case, the second main electrode 120 can be directly exposed on the terminal surface of the semiconductor device 200.

[0086] In addition, in the manufacturing method shown above, the order of each process can also be changed within a possible range. For example, S340 can be performed before S330, and the switching element 10 can be mounted on the mounting substrate 210 after joining each electrode plate to each wiring of the mounting substrate 210. In addition, S310 can be performed after S330, and the second main electrode plate 230 can be joined to the surface of the switching element 10 on the side closer to the second main electrode 120 after mounting the mounting substrate 210 on the switching element 10. In addition, any one of S300, S310, and S320 can be performed first, or they can be performed in parallel.

[0087] It should be noted that the semiconductor device 200 can include a temperature sensing diode or other temperature sensor for measuring the temperature of the semiconductor device 200 or the switching element 10. In this case, the semiconductor device 200 can have, for example, on the same surface as the first main electrode plate 220 or the like, an electrode plate connected to the electrodes of the temperature sensor such as the anode electrode and the cathode electrode of the temperature sensing diode.

[0088] In addition, the number of electrode plates disposed on the same surface as the first main electrode plate 220 and the like in the semiconductor device 200, as well as the size, shape, and type of each electrode plate, can be appropriately selected according to the usage mode of the semiconductor device 200, a temperature sensor or other additional circuits attached to the semiconductor device 200, and the like. For example, the area of the control electrode plate 240 of the semiconductor device 200 can be further reduced, and a new electrode plate can be provided at the position where a vacancy is generated thereby. As the newly provided electrode plate, for example, at least one of a sensing electrode plate electrically connected to the sensing electrode 130, one or more temperature sensing electrode plates respectively connected to the electrodes of the temperature sensor of the switching element 10 as described above, and an electrode plate (sub-electrode plate, etc.) having the same potential as the second main electrode plate 230 can be cited. In addition, for example, other electrode plates such as the second main electrode plate 230 can also be extended to the position where a vacancy is generated by reducing the area of the control electrode plate 240.

[0089] Such additional electrodes can be used to measure various electrical quantities for monitoring the state of the semiconductor device 200 or the switching element 10. Such additional electrodes can be disposed, for example, near the side where the control electrode plate 240 and the sub-electrode plate 250 are provided in the semiconductor device 200, at a position away from the large current flow paths such as the first main electrode plate 220, the second main electrode plate 230, and the main wirings connected to these main electrode plates. Thereby, the semiconductor device 200 can reduce the influence of at least one of noise and heat generation caused by the flow of a large current on the additional electrodes.

[0090] In addition, for example, a second sub-electrode plate different from the sub-electrode plate 250 can also be provided at the position where a vacancy is generated by reducing the area of the control electrode plate 240. The sub-electrode plate 250 (also referred to as the "first sub-electrode plate") and the second sub-electrode plate can be disposed on both sides of the control electrode plate 240 in such a manner that the control electrode plate 240 is sandwiched between the sub-electrode plates. To achieve such a configuration, in addition to the sub-wiring 530, the mounting substrate 210 can also have a second sub-wiring on the mounting surface of the switching element 10 that electrically connects the first main electrode 100 of the switching element 10 and the second sub-electrode plate. The sub-wiring 530 (also referred to as the "first sub-wiring") and the second sub-wiring can be disposed on both sides of the control wiring 520 in such a manner that the control wiring 520 is sandwiched between the sub-wirings. Thus, by adopting a configuration in which the control electrode plate 240 is sandwiched between two sub-electrode plates, the semiconductor device 200 can reduce the wiring inductance in the path of the current flowing through the semiconductor device 200 (i.e., the current of the control signal flowing through the control electrode 110 of the switching element 10).

[0091] Figure 12This shows the state in which the insulating layer 280 is disposed on the mounting substrate 210 in the second modification of the present embodiment. In Figure 6 in S325, in addition to mounting the insulating sheet that will become the insulating layer 280 on the mounting substrate 210 as shown in Figure 9 , the insulating layer 280 can also be laminated on the surface layer closer to the switching element 10 side in the first main electrode wiring 510 or the like by the method shown in this figure.

[0092] In the example of this figure, a liquid insulating material that will become the insulating layer 280 is coated on the surface of the mounting substrate 210 closer to the switching element 10 side. As an example, such an insulating material can be a thermosetting polyimide material. After coating the insulating material on the surface of the connection conductor 20 closer to the switching element 10 side, the insulating material can be thermally cured by heating the mounting substrate 210 to form the insulating layer 280.

[0093] Figure 13 This is a cross-section of the semiconductor device 200 in the third modification of the present embodiment. In Figure 6 in S325, when the insulating layer 280 is formed by coating the insulating material, depending on the amount and fluidity of the insulating material, the insulating material may spread to the area where a plurality of pillars 24 are formed on the mounting substrate 210 (such as the first main electrode contact 513 and the control electrode contact 523, etc.). Therefore, the areas of the connection conductors 20 such as the first main electrode wiring 510 and the control wiring 520 that are connected to the first main electrode 100 can have a structure that protrudes toward the first main electrode 100 side with respect to the area where the insulating layer 280 is disposed. Thus, the connection conductor 20 can have a step between the area to be connected to the first main electrode 100 and the area to be provided with the insulating layer 280, and this step prevents the insulating material from spreading to the area to be connected to the first main electrode 100.

[0094] By providing such a step, it is possible to prevent the insulating material from spreading to the area where the plurality of pillars 24 are provided. In addition, by using such a step, the range where the insulating layer 280 is disposed can be determined more accurately.

[0095] Figure 14Shows the state where the insulating layer 280 is disposed on the mounting substrate 210 in the fourth modification of the present embodiment. In the example of this figure, the connection conductors 20 such as the first main electrode wiring 510 and the control wiring 520 have a groove 285 between the regions of the first main electrode contact 513 and the control electrode contact 523 etc. that should be connected to the first main electrode 100 and the control electrode 110 etc. of the switching element 10, and the regions of the wirings 515 and 525 etc. where the insulating layer 280 should be disposed. The groove 285 prevents the insulating material from spreading to the regions that should be connected to the first main electrode 100 and the control electrode 110 etc. Such a groove 285 can be a groove whose thickness is shallower than the thickness of the conductor pattern 22 in the connection conductor 20 and does not impair the conductivity of the connection conductor 20.

[0096] By providing such a groove 285, even when a slightly excessive amount of insulating material is coated on the mounting substrate 210, it is possible to suppress the insulating material from spreading to the region where a plurality of posts 24 are provided.

[0097] Figure 15 Shows the state where the boundary wall 290 is disposed on the mounting substrate 210 in the fifth modification of the present embodiment. In the example of this figure, the Figure 6 coating of the insulating material in S325 is performed in two or more times.

[0098] This figure shows a state where a part of the insulating material that will become the insulating layer 280 is coated on the surface of the connection conductors 20 such as the first main electrode wiring 510 and the control wiring 520 on the side closer to the switching element 10, and a boundary wall 290 made of the insulating material is formed at the boundary between the region of the connection conductor 20 that should be connected to the first main electrode 100 and the region where the insulating layer 280 should be disposed. When forming the boundary wall 290, the insulating material can be temporarily coated on a part such as 1 / 2 or less or 1 / 4 or less of the region where the insulating layer 280 should finally be disposed. After coating a part of the insulating material in this way, the boundary wall 290 is formed by thermally curing the insulating material. When the viscosity of the insulating material is high enough to function as the boundary wall 290 even without thermal curing, the thermal curing for forming the boundary wall 290 can be omitted.

[0099] After forming the boundary wall 290, by coating another part of the insulating material on the side of the region where the insulating layer 280 should be disposed with respect to the boundary wall 290, the insulating layer 280 is formed. In this process, the insulating material coated at a position closer to the region where the insulating layer 280 should be disposed than the boundary wall 290 is blocked by the boundary wall 290. Therefore, according to this modification, it is possible to prevent the insulating material from spreading to the region of the connection conductor 20 that should be connected to the first main electrode 100.

[0100] As described above, the present invention has been illustrated by the embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. It is obvious that various changes or improvements can be made to the above embodiments by those skilled in the art. It can be clearly understood from the description of the claims that the embodiments with such changes or improvements can also be included in the technical scope of the present invention.

[0101] It should be noted that, as long as there is no special indication such as "before...", "prior to...", etc. for the execution order of each process such as actions, sequences, steps, stages, etc. in the devices, systems, programs, methods shown in the claims, the description, and the drawings, and as long as the output of the previous process is not used in the subsequent process, they can be implemented in any order. Regarding the action flow in the claims, the description, and the drawings, even if it is described using "firstly," "next," etc. for convenience, it does not mean that it must be implemented in that order.

Claims

1. A semiconductor device, characterized in that: have: A switching element having a first main electrode on one surface; a connecting conductor connected to the first main electrode of the switching element; a sealing portion that seals a space between the switching element and the connecting conductor; as well as An insulating layer is disposed between at least a portion of the switching element and the connection conductor so as to overlap with the sealing portion.

2. The semiconductor device according to claim 1, wherein: The insulating layer has a higher resistivity than a sealing material of the sealing portion.

3. The semiconductor device according to claim 1 or 2, characterized in that: The insulating layer is stacked on a surface of the connection conductor that is close to the switching element.

4. The semiconductor device according to claim 3, characterized in that The insulating layer faces a region including at least a portion of an outer edge portion of the switching element to an outer edge portion of a conductor exposed on a surface of the switching element on the connection conductor side, and is disposed on a surface of the connection conductor on the switching element side.

5. The semiconductor device according to claim 3, characterized in that A region of the connection conductor connected to the first main electrode protrudes toward the first main electrode relative to a region where the insulating layer is arranged.

6. The semiconductor device according to claim 3, characterized in that The connection conductor has a groove between a region connected to the first main electrode and a region where the insulating layer is arranged.

7. The semiconductor device according to claim 1, wherein: The insulating layer is stacked on a surface of the switching element that is closer to the connection conductor.

8. The semiconductor device according to any one of claims 1 to 7, characterized in that The connection conductor has a plurality of bumps that contact the first main electrode.

9. The semiconductor device according to any one of claims 1 to 8, characterized in that The semiconductor device includes a mounting substrate having the connection conductor on a mounting surface on which the switching element is mounted, and a first main electrode plate connected to the connection conductor in a region of the mounting surface where the switching element is not arranged.

10. The semiconductor device according to claim 9, characterized in that The semiconductor device includes a second main electrode plate connected to the second main electrode of the switching element. The mounting substrate has a control electrode plate connected to the control electrode of the switching element. The first main electrode plate, the second main electrode plate, and the control electrode plate are exposed on one surface of the semiconductor device.

11. The semiconductor device according to claim 9 or 10, characterized in that: The mounting substrate has a heat conduction plate formed on a surface opposite to the mounting surface.

12. The semiconductor device according to any one of claims 1 to 11, characterized in that The switching element is a power MOSFET, an IGBT, or a SiC semiconductor element.

13. A method for manufacturing a semiconductor device, characterized in that: include: preparing a switching element having a first main electrode on one surface; an insulating layer is disposed at a position between at least a portion of the switching element and a connection conductor to be connected to the first main electrode; Connecting the connection conductor to the first main electrode of the switching element; as well as The space between the switching element and the connecting conductor is sealed by a sealing material.

14. The manufacturing method according to claim 13, characterized in that: The step of disposing the insulating layer includes the step of laminating the insulating layer on a surface of the connection conductor on the switching element side.

15. The manufacturing method according to claim 14, characterized in that: The step of laminating the insulating layer on the surface of the connection conductor on the switching element side includes the step of mounting an insulating sheet serving as the insulating layer on the surface of the connection conductor on the switching element side.

16. The manufacturing method according to claim 14, characterized in that: The step of laminating the insulating layer on the surface of the connection conductor on the switching element side includes the step of applying an insulating material to be the insulating layer on the surface of the connection conductor on the switching element side.

17. The manufacturing method according to claim 16, characterized in that: The connection conductor has a step between a region to be connected to the first main electrode and a region to be provided with the insulating layer, and the step prevents the insulating material from spreading to the region to be connected to the first main electrode.

18. The manufacturing method according to claim 16, characterized in that: The connection conductor has a groove between a region to be connected to the first main electrode and a region to be provided with the insulating layer, and the groove prevents the insulating material from spreading to the region to be connected to the first main electrode.

19. The manufacturing method according to claim 16, characterized in that: The process of applying the insulating material comprises: A portion of the insulating material that becomes the insulating layer is applied to a surface of the connection conductor on the switching element side, and a boundary wall made of the insulating material is formed at a boundary between a region of the connection conductor to be connected to the first main electrode and a region to be provided with the insulating layer; and The insulating layer is formed by applying another portion of the insulating material on a region side of the boundary wall where the insulating layer is to be disposed.

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