Semiconductor device, power conversion device, and method for manufacturing semiconductor device

Abstract

A semiconductor device, a power conversion device, and a manufacturing method of a semiconductor device capable of reducing manufacturing cost are obtained. A metal pattern (3) is provided on an insulating resin (2). A semiconductor chip (4) is bonded to the metal pattern (3). A case (7) is bonded to the insulating resin (2) so as to surround the semiconductor chip (4). A sealing material (9) seals the semiconductor chip (4) inside the case (7). A lid (11) is provided on an upper portion of the case (7) and covers the semiconductor chip (4) and the sealing material (9). A V-shaped groove (10) is provided in the lid (11).

Description

TECHNICAL FIELD

[0001] The present application relates to a semiconductor device, a power conversion device, and a manufacturing method of a semiconductor device. BACKGROUND

[0002] In the case of a semiconductor device for power, a lid is fixed to an upper portion of a case that houses a semiconductor chip in order to protect the semiconductor chip from the external environment (see, for example, Patent Literature 1).

[0003] Patent Literature 1: International Publication No. 2018 / 207279

[0004] The size of the case differs depending on the product of the semiconductor device. Conventionally, a lid corresponding to the size of the case has been prepared separately. Therefore, a plurality of molds for molding the lid have been required, and there has been a problem of a large manufacturing cost. SUMMARY

[0005] The present application has been made in order to solve the above-described problems, and has an object to obtain a semiconductor device, a power conversion device, and a manufacturing method of a semiconductor device, which can reduce the manufacturing cost.

[0006] The semiconductor device according to the present application is characterized by including: an insulating resin; a metal pattern provided on the insulating resin; a semiconductor chip joined to the metal pattern; a case bonded to the insulating resin so as to surround the semiconductor chip; a packaging material that packages the semiconductor chip inside the case; and a lid provided on an upper portion of the case so as to cover the semiconductor chip and the packaging material, the lid being provided with a V-shaped groove.

[0007] EFFECT OF THE INVENTION

[0008] In the present application, the lid is provided with the V-shaped groove. By dividing the lid along the groove, the size of the lid can be easily adjusted in a manner that matches the size in the planar direction of the case of the semiconductor device having different specifications or sizes. Therefore, the shape of the molded lid is standardized, and thus it is not necessary to design a molding die for a plurality of lids having different sizes, to manage the inventory of a plurality of lids, or to resin-mold a plurality of lids. Therefore, the manufacturing cost can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0009] Figure 1 is a cross-sectional view showing a semiconductor device according to Embodiment 1.

[0010] Figure 2 is a cross-sectional view showing a lid according to Embodiment 1.

[0011] Figure 3 is a cross-sectional view showing a lid according to Embodiment 1.

[0012] Figure 4 is a perspective view of the lower surface side of the cover of Figure 3

[0013] Figure 5 is a sectional view of the cover according to Embodiment 1.

[0014] Figure 6 is a perspective view of the lower surface side of the cover of Figure 5

[0015] Figure 7 is a sectional view of the manufacturing method of the semiconductor device according to Embodiment 1.

[0016] Figure 8 is a sectional view of the cover according to Embodiment 2.

[0017] Figure 9 is a sectional view of the semiconductor device according to Embodiment 2.

[0018] Figure 10 is a sectional view of the cover according to Embodiment 3.

[0019] Figure 11 is a perspective view of the lower surface side of the cover of Figure 10

[0020] Figure 12 is a block diagram showing the structure of a power conversion system to which the power conversion device according to Embodiment 4 is applied. DETAILED DESCRIPTION

[0021] A semiconductor device, a power conversion device, and a manufacturing method of a semiconductor device according to the embodiments will be described with reference to the drawings. The same reference numerals are assigned to the same or corresponding structural elements, and repeated description will be omitted.

[0022] Embodiment 1

[0023] Figure 1 is a sectional view of the semiconductor device according to Embodiment 1. The base plate 1 is composed of copper or aluminum having a high thermal conductivity. An insulating resin 2 composed of a resin such as an epoxy resin is provided on the base plate 1. A metal pattern 3 constituting a circuit is provided on the insulating resin 2. A lower surface electrode of a semiconductor chip 4 is joined to the metal pattern 3 through a joining material 5. A wire 6 is wire-bonded to an upper surface electrode of the semiconductor chip 4. A case 7 composed of a PPS or PBT resin is adhered to an upper surface of the insulating resin 2 so as to surround the metal pattern 3, the semiconductor chip 4, and the wire 6, by an adhesive 8 having silicone as a main component. In addition, a control substrate can be built in the inside of the case 7. The case 7 can be adhered to the base plate 1. ​​​

[0024] The encapsulating material 9 encapsulates the metal pattern 3, the semiconductor chip 4, and the lead 6 in the inside of the case 7. The encapsulating material 9 has a thermosetting resin such as an epoxy resin, a phenol resin, or a polyimide resin, and has insulating properties, heat resistance, and adhesive properties.

[0025] The groove 10 of a V-shaped section is provided on the lower surface of the plate-shaped cover 11. The cover 11 is divided along the groove 10 so as to match the size of the case 7. The cover 11 is divided in order to apply a load, and the depth of the groove 10 is set to be greater than or equal to 1 / 3 of the thickness of the cover 11, and the angle of the V-shape is set to be less than or equal to 90°. Further, the groove 10 can be provided on the upper surface of the cover 11.

[0026] The protrusion 12 composed of a PPS or PBT resin is provided on the lower surface of the cover 11. The tip portion of the protrusion 12 is encapsulated by the encapsulating material 9. The through-hole 13 is provided on the tip portion of the protrusion 12. The through-hole 13 is filled with the encapsulating material 9 to exert an anchoring effect. The shape of the through-hole 13 is not limited to a circular shape, and can be a square shape, a necked shape, or the like, as long as the anchoring effect can be obtained.

[0027] Figure 2 Figure 3 Figure 5 is a cross-sectional view showing the cover according to Embodiment 1. Figure 4 is a perspective view showing the lower surface side of the cover of Figure 3 Figure 6 is a perspective view showing the lower surface side of the cover of Figure 5 . In Figure 2 , the groove 10 is provided between the protrusions 12. In Figure 3 and Figure 4 , the groove 10 is provided in a cross shape on the lower surface of the cover 11. In Figure 5 and Figure 6 , the interval of the groove 10 is changed in the drawing transverse direction. In this way, the groove 10 is arranged so as to match the product line up. The position and the number of the protrusions 12 are also arranged so as to match the product.

[0028] Figure 7 is a cross-sectional view showing a manufacturing method of the semiconductor device according to Embodiment 1. First, the semiconductor chip 4 is bonded to the metal pattern 3 on the insulating resin 2. The lead 6 is wire-bonded to the upper surface electrode of the semiconductor chip 4. The case 7 is adhered to the insulating resin 2 so as to surround the semiconductor chip 4 and the like. The encapsulating material 9 is injected into the inside of the case 7 to encapsulate the semiconductor chip 4 and the like. Further, the case 7 can be adhered to the base plate 1.

[0029] In the case 7 where the size is large, as in Figure 1 ​​​​The lid 11 is used as shown in a state where the lid 11 is not divided along the groove 10. On the other hand, in a case where the size of the case 7 is small, the lid 11 is divided along the groove 10 in a manner matching the size of the case 7 as shown in a state where a load is applied to the lid 11. Since the small-sized lid 11 remaining after the division can be used for other kinds of small-sized cases, it is possible to use without waste. Therefore, the number of production of the lid 11 can be reduced. Figure 7

[0030] The divided lid 11 is covered on the upper portion of the case 7 to cover the semiconductor chip 4 and the encapsulating material 9. The tip portion of the protrusion 12 is inserted into the encapsulating material 9 before curing. Then, if the encapsulating material 9 is cured by heating, the lid 11 is fixed.

[0031] As described above, in the present embodiment, the V-shaped groove 10 is provided in the lid 11. By dividing the lid 11 along the groove 10, the size of the lid 11 can be easily adjusted in a manner matching the size of the planar direction of the case 7 of the semiconductor device of different specifications or sizes. Therefore, the shape of the molded lid 11 is standardized, and thus it is not necessary to design the molding mold for a plurality of lids of different sizes, to manage the inventory of a plurality of lids, or to resin-mold a plurality of lids. Therefore, the manufacturing cost can be reduced.

[0032] In addition, the through-hole 13 is provided in the tip portion of the protrusion 12, and the encapsulating material 9 is encapsulated. Therefore, the lid 11 can be easily fixed by the anchoring effect, and thus it is not necessary to use an adhesive between the lid 11 and the case 7. However, the lid 11 can be adhered to the upper surface of the case 7 by an adhesive or an encapsulating material. Thus, the lid 11 can be stably fixed.

[0033] In addition, in a case where the protrusion 12 is adhered to the lower surface of the lid 11, it is difficult to position the protrusion 12, and there is a concern that the protrusion 12 interferes with the internal components such as the semiconductor chip 4 or the lead 6. Therefore, in the present embodiment, the lid 11 and the protrusion 12 are integrally molded by a resin such as PPS or PBT.

[0034] Embodiment 2

[0035] Figure 8 is a sectional view showing the lid involved in Embodiment 2. Since the V-shaped groove 10 is provided in the lid 11 in the same manner as in Embodiment 1, the size of the lid 11 can be easily adjusted in a manner matching the size of the case 7. Therefore, the manufacturing cost can be reduced.

[0036] ​In Embodiment 1, the lid 11 and the protrusion 12 are integrated, but in the present embodiment, the lid 11 and the protrusion 12 are separate components that are resin-molded separately and used by combining them with each other. The lid 11 is provided with an opening 14. The opening 14 has a counterbore 15 on the upper surface side of the lid 11. The protrusion 12 has a protrusion main body 12a and a wide portion 12b provided on the upper portion of the protrusion main body 12a and having a width wider than that of the protrusion main body 12a. The counterbore 15 and the wide portion 12b are tapered, for example, at 45°, in correspondence with each other.

[0037] The protrusion main body 12a is inserted into the opening 14 and protrudes from the lower surface of the lid 11. The wide portion 12b is fitted into the counterbore 15. The tapered shapes of the wide portion 12b and the counterbore 15 match each other.

[0038] Figure 9 is a sectional view showing a semiconductor device to which Embodiment 2 is applied. After the encapsulating material 9 is injected into the case 7, the divided lid 11 is placed on the upper portion of the case 7 to cover the semiconductor chip 4 and the encapsulating material 9. The divided lid 11 is placed on the upper portion of the case 7 to cover the semiconductor chip 4 and the encapsulating material 9. The protrusion 12 is inserted into the opening 14 of the lid 11, and the tip portion of the protrusion 12 is inserted into the encapsulating material 9 before curing. Then, if the encapsulating material 9 is cured, the lid 11 and the protrusion 12 are fixed. Further, in the case where the protrusion 12 is floated and protrudes from the lid 11 before the encapsulating material 9 is cured, a load can be placed on the protrusion 12 to prevent the floating until the encapsulating material 9 is cured.

[0039] As described above, in the present embodiment, the lid 11 and the protrusion 12 are separate components that are resin-molded separately. Since the lid 11 before being combined with the protrusion 12 is flat, a plurality of lids 11 can be stacked. Therefore, the space for preparing the lid 11 can be reduced. The supply work of the protrusion 12 can be performed using a feeder or the like in a space-saving manner.

[0040] In addition, the protrusion 12 can be combined with the lid 11 only by inserting the protrusion 12 into the opening 14 of the lid 11. Furthermore, the arrangement of the protrusion 12 can be set accurately. In addition, the wide portion 12b of the protrusion 12 is fitted into the counterbore 15 of the opening 14 of the lid 11, and the tapered shapes of the wide portion 12b and the counterbore 15 match each other. Thus, the protrusion 12 is positioned and prevented from falling off.

[0041] Embodiment 3

[0042] Figure 10 is a sectional view showing a lid to which Embodiment 3 is applied. Figure 11 is a sectional view showing Figure 10FIG. 6 is a perspective view of the lower surface side of the cover 11. Since the groove 10 in the V shape is provided in the cover 11 as in Embodiment 1, the size of the cover 11 can be easily adjusted in a manner matching the size of the case 7. Therefore, the manufacturing cost can be reduced.

[0043] In Embodiment 1, the cover 11 and the protrusions 12 are integrated, but in the present embodiment, the cover 11 and the protrusions 12 are separate components that are resin-molded separately and used by being combined with each other. The protrusion 12 has a protrusion main body 12a and a wide portion 12b provided at the upper portion of the protrusion main body 12a and having a width wider than that of the protrusion main body 12a. A hook-shaped holding portion 16 that holds the wide portion 12b of the protrusion 12 is provided on the lower surface of the cover 11. By holding the wide portion 12b of the protrusion 12 with the holding portion 16, it is possible to prevent the protrusion 12 from falling.

[0044] As described above, in the present embodiment, the cover 11 and the protrusions 12 are separate components that are resin-molded separately. Since the cover 11 before being combined with the protrusions 12 is flat, a plurality of covers 11 can be stacked. Therefore, the space for preparing the covers 11 can be reduced. The supply work of the protrusions 12 can be performed using a feeder or the like in a manner saving space.

[0045] In addition, the protrusion 12 can be combined with the cover 11 by merely engaging the wide portion 12b of the protrusion 12 with the holding portion 16 of the cover 11. Furthermore, the arrangement of the protrusion 12 can be accurately set. In addition, since the protrusion 12 is arranged on the lower surface of the cover 11, the protrusion 12 does not protrude from the cover 11 by floating up due to the expansion of the sealing material 9 at the time of sealing or the like. In addition, since the upper surface of the cover 11 is flat without an opening, the appearance does not change even if the protrusion 12 is not arranged on all of the holding portions 16 of the cover 11. Therefore, the protrusion 12 can not be arranged at a portion where the protrusion 12 cannot be arranged due to a limitation of the configuration of the semiconductor device or the like. The other structures and effects are the same as in Embodiments 1 and 2.

[0046] In Embodiments 2 and 3, the length and the width of the plurality of protrusions 12 need not be the same, and can be changed in a manner matching the size or the shape of the device. For example, the protrusions 12 of the central portion of the case 7 can be made shorter than the protrusions 12 of the outer peripheral portion of the case 7 in a manner that the protrusions 12 do not come into contact with the semiconductor chip 4 and the lead 6 arranged in the central portion of the case 7. By making the protrusions 12 long at a portion where the semiconductor chip 4 and the lead 6 are not present and making the protrusions 12 deep at the insertion of the sealing material 9, it is possible to firmly fix the cover 11.

[0047] Further, the semiconductor chip 4 is not limited to being formed of silicon, and can be formed of a wide bandgap semiconductor having a larger bandgap than silicon. The wide bandgap semiconductor is, for example, silicon carbide, a gallium nitride-based material, or diamond. Since the semiconductor chip formed of such a wide bandgap semiconductor has high withstand voltage and allows a high current density, it can be miniaturized. By using the semiconductor chip that has been miniaturized, the semiconductor device in which the semiconductor chip is mounted can also be miniaturized and highly integrated. In addition, since the semiconductor chip has high heat resistance, it is possible to miniaturize the heat dissipation fins of a heat sink, to air-cool a water cooling portion, and thus to further miniaturize the semiconductor device. In addition, since the semiconductor chip has low power loss and is highly efficient, it is possible to make the semiconductor device highly efficient.

[0048] Embodiment 4

[0049] In this embodiment, the semiconductor device related to Embodiments 1 to 3 described above is applied to a power conversion device. The power conversion device is, for example, an inverter device, a converter device, a servo amplifier, a power supply unit, or the like. The present application is not limited to a specific power conversion device, and in the following, a case in which the present application is applied to a three-phase inverter will be described.

[0050] Figure 12 is a block diagram showing the structure of a power conversion system to which the power conversion device related to Embodiment 4 is applied. The power conversion system has a power supply 100, a power conversion device 200, and a load 300. The power supply 100 is a direct current power supply, and supplies direct current power to the power conversion device 200. The power supply 100 can be configured from various power supplies, and for example, can be configured from a direct current system, a solar cell, a storage battery, or can be configured from a rectification circuit or an AC / DC converter connected to an alternating current system. In addition, the power supply 100 can be configured from a DC / DC converter that converts direct current power output from a direct current system into prescribed power.

[0051] The power conversion device 200 is a three-phase inverter connected between the power supply 100 and the load 300, and converts direct current power supplied from the power supply 100 into alternating current power, and supplies the alternating current power to the load 300. The power conversion device 200 has a main conversion circuit 201 that converts direct current power into alternating current power and outputs it, and a control circuit 203 that outputs a control signal that controls the main conversion circuit 201 to the main conversion circuit 201.

[0052] The load 300 is a three-phase motor that is driven by alternating current power supplied from the power conversion device 200. Further, the load 300 is not limited to a specific use, and is a motor mounted on various electric appliances, and for example, is used as a motor for a hybrid automobile, an electric automobile, a railway vehicle, an elevator, or an air conditioning device.

[0053] The power conversion device 200 will be described in detail below. The main conversion circuit 201 has switching elements and freewheeling diodes (not shown) and converts the direct-current power supplied from the power supply 100 into alternating-current power by switching the switching elements on and off, and supplies the alternating-current power to the load 300. The specific circuit structure of the main conversion circuit 201 is various, but the main conversion circuit 201 according to the present embodiment is a 2-level three-phase full-bridge circuit and can be configured by six switching elements and six freewheeling diodes respectively connected in antiparallel with the switching elements. Each of the switching elements and the freewheeling diodes of the main conversion circuit 201 is configured by the semiconductor device 202 corresponding to any of the above-described Embodiments 1 to 4. The six switching elements are connected in series two by two to configure upper and lower arms, and each of the upper and lower arms configures each phase (U phase, V phase, W phase) of the full-bridge circuit. Furthermore, the output terminals of each of the upper and lower arms, that is, the three output terminals of the main conversion circuit 201 are connected to the load 300.

[0054] In addition, the main conversion circuit 201 has a drive circuit (not shown) that drives each of the switching elements, but the drive circuit can be built into the semiconductor device 202 or can be configured to have a drive circuit separate from the semiconductor device 202. The drive circuit generates drive signals that drive the switching elements of the main conversion circuit 201 and supplies the drive signals to the control electrodes of the switching elements of the main conversion circuit 201. Specifically, in accordance with a control signal from the control circuit 203 described later, a drive signal that causes the switching elements to be in the on state and a drive signal that causes the switching elements to be in the off state are output to the control electrodes of each of the switching elements. In the case where the switching elements are maintained in the on state, the drive signal is a voltage signal (on signal) greater than or equal to the threshold voltage of the switching elements, and in the case where the switching elements are maintained in the off state, the drive signal is a voltage signal (off signal) less than or equal to the threshold voltage of the switching elements.

[0055] The control circuit 203 controls the switching elements of the main conversion circuit 201 to supply the desired power to the load 300. Specifically, the time (on time) during which each of the switching elements of the main conversion circuit 201 should be in the on state is calculated based on the power that should be supplied to the load 300. For example, the main conversion circuit 201 can be controlled by PWM control that modulates the on time of the switching elements in accordance with the voltage that should be output. Furthermore, a control command (control signal) is output to the drive circuit possessed by the main conversion circuit 201 so that the on signal is output to the switching elements that should be in the on state and the off signal is output to the switching elements that should be in the off state at each time. The drive circuit outputs the on signal or the off signal as a drive signal to the control electrode of each of the switching elements in accordance with the control signal.

[0056] In the power conversion device according to the present embodiment, since the semiconductor device according to Embodiments 1 to 3 is used as the semiconductor device 202, the manufacturing cost of the power conversion device can be reduced.

[0057] In the present embodiment, an example in which the present application is applied to a 2-level three-phase inverter is described, but the present application is not limited to this, and can be applied to various power conversion devices. In the present embodiment, a 2-level power conversion device is assumed, but the present application can be applied to a 3-level or a multi-level power conversion device, and can be applied to a single-phase inverter in the case where power is supplied to a single-phase load. In addition, in the case where power is supplied to a DC load or the like, the present application can be applied to a DC / DC converter or an AC / DC converter.

[0058] In addition, the power conversion device to which the present application is applied is not limited to the case where the load is a motor, and for example, can be used as a power supply device for an electric discharge machine, a laser machine, or an induction heating cooker or a non-contact power supply system, and can be used as a power conditioner for a solar power generation system or an electric storage system or the like.

[0059] Explanation of Reference Numerals

[0060] 2: Insulating resin, 3: Metal pattern, 4: Semiconductor chip, 7: Housing, 9: Encapsulation material, 10: Groove, 11: Cover, 12: Protrusion, 12a: Protrusion main body, 12b: Wide portion, 13: Through-hole, 14: Opening, 15: Counterbore, 16: Retaining portion, 200: Power conversion device, 201: Main conversion circuit, 202: Semiconductor device, 203: Control circuit

Claims

1. A semiconductor device, characterized in that, have: Insulating resin; Metallic patterns are disposed on the insulating resin; A semiconductor chip, which is bonded to the metal pattern; A housing that is bonded to the insulating resin in a manner that surrounds the semiconductor chip; An encapsulation material that encapsulates the semiconductor chip inside the housing; as well as A cover, disposed on the upper part of the housing, covers the semiconductor chip and the packaging material. A V-shaped groove is provided at the location corresponding to the packaging material when the cover is viewed from above. The encapsulation material is a thermosetting resin. A protrusion is provided on the lower surface of the cover. The top of the protrusion is encapsulated by the encapsulation material. The cover and the protrusion are separate components. The cover is provided with an opening having a countersunk hole. The protrusion has a protruding body and a wide portion, the wide portion being disposed on the upper part of the protruding body and being wider than the protruding body. The protruding body is inserted into the opening and protrudes from the lower surface of the cover. The wide section fits into the countersunk hole.

2. The semiconductor device according to claim 1, characterized in that, A through hole is provided at the top end.

3. The semiconductor device according to claim 1, characterized in that, The countersunk hole and the wide section are conical in shape, corresponding to each other.

4. The semiconductor device according to claim 1, characterized in that, The protrusion has multiple protrusions of different lengths or widths.

5. The semiconductor device according to claim 3, characterized in that, The protrusion has multiple protrusions of different lengths or widths.

6. The semiconductor device according to any one of claims 1 to 3, characterized in that, The semiconductor chip is formed from a wide-bandgap semiconductor.

7. A semiconductor device, characterized in that, have: Insulating resin; Metallic patterns are disposed on the insulating resin; A semiconductor chip, which is bonded to the metal pattern; A housing that is bonded to the insulating resin in a manner that surrounds the semiconductor chip; An encapsulation material that encapsulates the semiconductor chip inside the housing; as well as A cover, disposed on the upper part of the housing, covers the semiconductor chip and the packaging material. A V-shaped groove is provided at the location corresponding to the packaging material when the cover is viewed from above. The encapsulation material is a thermosetting resin. A protrusion is provided on the lower surface of the cover. The top of the protrusion is encapsulated by the encapsulation material. The cover and the protrusion are separate components. The protrusion has a protruding body and a wide portion, the wide portion being disposed on the upper part of the protruding body and being wider than the protruding body. A retaining part is provided on the lower surface of the cover to hold the wide portion.

8. The semiconductor device according to claim 7, characterized in that, The protrusion has multiple protrusions of different lengths or widths.

9. The semiconductor device according to claim 7, characterized in that, The semiconductor chip is formed from a wide-bandgap semiconductor.

10. A power conversion device, characterized in that, have: A main conversion circuit having a semiconductor device according to any one of claims 1 to 9, the main conversion circuit converting the input power into an output; as well as The control circuit outputs control signals to the main conversion circuit to control the main conversion circuit.

11. A method for manufacturing a semiconductor device, characterized in that, It has the following processes: Semiconductor chips are bonded to a metal pattern in insulating resin. The housing is bonded to the insulating resin in a manner that surrounds the semiconductor chip; The semiconductor chip is encapsulated by injecting encapsulation material into the interior of the housing; The cover with the V-shaped groove is divided along the groove in a manner that matches the size of the housing; as well as The divided cover is placed over the upper part of the housing to cover the semiconductor chip and the packaging material. The groove exists at the location corresponding to the encapsulation material when viewed from above, where the cover is divided and covered by the housing.

12. The method for manufacturing a semiconductor device according to claim 11, characterized in that, The encapsulation material is a thermosetting resin. A protrusion is provided on the lower surface of the cover. The top of the protrusion is inserted into the uncured encapsulation material, and the cap is fixed by heating the encapsulation material to cure it.

Images