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

Abstract

The invention provides a semiconductor module, a power semiconductor device, a method for manufacturing the semiconductor module and the power semiconductor device, and a power conversion device, wherein the reliability of a joint part between the semiconductor module and a cooler can be improved. The insulating substrate has an insulating plate, a front surface metal pattern formed on the front surface of the insulating plate, and a back surface metal pattern formed on the back surface of the insulating plate. The semiconductor chip is mounted on the surface metal pattern of the insulating substrate. The main terminal is connected to the main electrode of the upper surface of the semiconductor chip. The signal terminal is connected with a control electrode on the upper surface of the semiconductor chip through a lead. The sealing resin seals the insulating substrate, the semiconductor chip, the lead, a part of the main terminal, and a part of the signal terminal. The back surface metal pattern protrudes from the lower surface of the sealing resin and the side surfaces and the lower surface of the back surface metal pattern are exposed from the sealing resin. The exposed surface of the back metal pattern is modified and cured. The back surface metal pattern has a convex shape warped downward.

Description

Technical Field

[0001] The present disclosure relates to a semiconductor module, a power semiconductor device, a method for manufacturing a semiconductor module, a method for manufacturing a power semiconductor device, and a power conversion device. Background Art

[0002] A semiconductor module is disclosed in which a semiconductor chip is soldered to an insulating substrate, a wire is bonded to an upper surface of a semiconductor element, and resin-sealed by transfer molding (for example, see Patent Document 1).

[0003] Patent Document 1: International Publication No. 2014 / 006724

[0004] Since the semiconductor module is joined to the cooler via heat dissipation grease or solder, it is necessary to improve the reliability of the joint between the semiconductor module and the cooler. Summary of the invention

[0005] The present disclosure is made to solve the above-mentioned problems, and its purpose is to provide a semiconductor module, a power semiconductor device, a method for manufacturing a semiconductor module, a method for manufacturing a power semiconductor device, and a power conversion device that can improve the reliability of the joint between the semiconductor module and the cooler.

[0006] The semiconductor module involved in the present disclosure is characterized in that it comprises: an insulating substrate having an insulating plate, a surface metal pattern formed on the surface of the above-mentioned insulating plate, and a back metal pattern formed on the back of the above-mentioned insulating plate; a semiconductor chip mounted on the above-mentioned surface metal pattern of the above-mentioned insulating substrate; a main terminal connected to the main electrode on the upper surface of the above-mentioned semiconductor chip; a signal terminal connected to the control electrode on the upper surface of the above-mentioned semiconductor chip through a lead; and a sealing resin that seals the above-mentioned insulating substrate, the above-mentioned semiconductor chip, the above-mentioned lead, a part of the above-mentioned main terminal and a part of the above-mentioned signal terminal, the above-mentioned back metal pattern protrudes from the lower surface of the above-mentioned sealing resin and the side surface and the lower surface of the above-mentioned back metal pattern are exposed from the above-mentioned sealing resin, the exposed surface of the above-mentioned back metal pattern is modified and solidified, and the above-mentioned back metal pattern has a convex shape warped downward.

[0007] The manufacturing method of the semiconductor module according to the present disclosure is characterized by comprising: a step of mounting a semiconductor chip on the surface metal pattern of an insulating substrate having an insulating plate, a surface metal pattern formed on the surface of the insulating plate, and a back metal pattern formed on the back of the insulating plate; a step of connecting a main terminal to a main electrode on the upper surface of the semiconductor chip; a step of connecting a signal terminal to a control electrode on the upper surface of the semiconductor chip through a lead; a step of sealing the insulating substrate, the semiconductor chip, the lead, a part of the main terminal, and a part of the signal terminal with a sealing resin; and a step of performing a shot peening process by simultaneously projecting particles onto an exposed surface of the back metal pattern exposed from the lower surface of the sealing resin and a lower surface of the sealing resin, wherein before the shot peening process, the lower surface of the back metal pattern is coplanar with the lower surface of the sealing resin, and after the shot peening process, the back metal pattern protrudes from the lower surface of the sealing resin and a side surface of the back metal pattern is exposed from the sealing resin, the exposed surface of the back metal pattern after the shot peening process is modified and solidified, and the back metal pattern after the shot peening process has a convex shape that is warped downward.

[0008] In the present disclosure, the back metal pattern protrudes from the lower surface of the sealing resin, and the side and lower surface of the back metal pattern are exposed from the sealing resin, and the exposed surface of the back metal pattern is modified and solidified, and the back metal pattern is in a convex shape warped downward. Thus, the reliability of the joint between the semiconductor module and the cooler can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a side view showing the semiconductor module according to the first embodiment.

[0010] Figure 2 It is a cross-sectional view showing the semiconductor module according to the first embodiment.

[0011] Figure 3 It is a bottom view showing the semiconductor module according to the first embodiment.

[0012] Figure 4 It is a cross-sectional view showing the back metal pattern after modification and curing.

[0013] Figure 5 This is a side view showing the power semiconductor device according to the first embodiment.

[0014] Figure 6 This is a flowchart showing a method for manufacturing the semiconductor module and the power semiconductor device according to the first embodiment.

[0015] Figure 7 It is a cross-sectional view showing the method for manufacturing the semiconductor module according to the first embodiment.

[0016] Figure 8 It is a cross-sectional view showing the method for manufacturing the semiconductor module according to the first embodiment.

[0017] Fig. 9 It is a side view showing the semiconductor module according to the second embodiment.

[0018] Fig.10 It is a bottom view showing the semiconductor module according to the second embodiment.

[0019] Fig.11 It is a side view showing a power semiconductor device according to the second embodiment.

[0020] Fig.12 It is a side view showing a power semiconductor device according to the second embodiment.

[0021] Fig.13 This is an enlarged side view of a junction portion of the power semiconductor device according to the second embodiment.

[0022] Fig.14 It is a side view showing a modification of the semiconductor module according to the second embodiment.

[0023] Fig.15 It is a bottom view showing a modification of the semiconductor module according to the second embodiment.

[0024] Fig.16 It is a cross-sectional view showing a power semiconductor device according to the third embodiment.

[0025] Fig.17 It is a cross-sectional view showing a modification of the power semiconductor device according to the third embodiment.

[0026] Fig.18 This is a flowchart showing a method for manufacturing a semiconductor module and a power semiconductor device according to the third embodiment.

[0027] Fig.19 It is a cross-sectional view showing a power semiconductor device according to a fourth embodiment.

[0028] Fig. 20 It is a cross-sectional view showing a modification of the power semiconductor device according to the fourth embodiment.

[0029] Fig.21 This is a flowchart showing a method for manufacturing a semiconductor module and a power semiconductor device according to the fourth embodiment.

[0030] Fig. 22This is a block diagram showing the configuration of a power conversion system to which the power conversion device according to the fifth embodiment is applied.

[0031] Description of Reference Numerals

[0032] 1...insulating substrate; 1a...insulating plate; 1b...surface metal pattern; 1c...back metal pattern; 1ca...surface layer; 1cb...interior; 2...semiconductor chip; 3, 5, 11...joining material; 4, 6...main terminal; 7a, 7b...signal terminal; 8...lead; 9...sealing resin; 10...step difference; 12, 21...cooler; 13...plurality of fins; 14a...first protrusion; 14b...second protrusion; 15...recess; 16...lower cooler; 17...resin case; 18...mounting hole; 19...screw; 20...external terminal; 200...power conversion device; 201...main conversion circuit; 202...semiconductor device; 203...control circuit. DETAILED DESCRIPTION

[0033] The semiconductor module, the power semiconductor device, the method for manufacturing the semiconductor module, the method for manufacturing the power semiconductor device, and the power conversion device according to the embodiments are described with reference to the accompanying drawings. The same or corresponding components are sometimes denoted by the same reference numerals, and repeated descriptions are omitted.

[0034] Implementation Method 1

[0035] Figure 1 It is a side view showing the semiconductor module according to the first embodiment. Figure 2 It is a cross-sectional view showing the semiconductor module according to the first embodiment. Figure 3 It is a bottom view showing the semiconductor module according to the first embodiment.

[0036] The insulating substrate 1 includes an insulating plate 1a, a surface metal pattern 1b formed on the surface of the insulating plate 1a, and a back metal pattern 1c formed on the back of the insulating plate 1a. The insulating plate 1a is made of ceramics such as AlN (aluminum nitride), Al2O3, (aluminum oxide) or Si3N4 (silicon nitride).

[0037] The surface metal pattern 1b and the back metal pattern 1c are conductive metals, such as metals with copper or aluminum as the main component. The surface metal pattern 1b and the back metal pattern 1c are joined to the insulating plate 1a by brazing. The thickness of the surface metal pattern 1b and the back metal pattern 1c is 0.2 mm to 1.0 mm, and the thickness of the two can be the same or different. The thickness of the surface metal pattern 1b and the back metal pattern 1c is determined by the specifications (rated current) of the semiconductor module. The thicker these patterns are, the more they can cope with high current and miniaturization.

[0038] A semiconductor chip 2 is mounted on the surface metal pattern 1b of the insulating substrate 1. The lower surface electrode of the semiconductor chip 2 is bonded to the surface metal pattern 1b of the insulating substrate 1 via a bonding material 3. The bonding material 3 is a sintered material composed of fine metal powder.

[0039] The main electrode on the upper surface of the semiconductor chip 2 is bonded to the main terminal 4 via a bonding material 5. The other main terminal 6 is bonded to the surface metal pattern 1b of the insulating substrate 1 via the bonding material 5. Although the bonding material 5 is solder, it can also be a sintered material. The control electrode on the upper surface of the semiconductor chip 2 is connected to the signal terminal 7a via a lead 8. The other surface metal pattern 1b is connected to the signal terminal 7b via a lead 8. The main terminals 4, 6 and the signal terminals 7a, 7b are conductive metals, such as copper or copper alloys. The lead 8 is a conductive metal with any one of aluminum, gold, silver, and copper as the main component, and is ultrasonically bonded to the control electrode and signal terminal 7a of the semiconductor chip 2, and the surface metal pattern 1b and the signal terminal 7b.

[0040] The semiconductor chip 2 is a diode, a MOSFET (Metal-Oxide-Semiconductor Field-EffectTransistor), an IGBT (Insulated-Gate BipolarTransistor), or an RC-IGBT (Reverse-Conducting IGBT). The semiconductor chip 2 can also be a semiconductor chip with multiple functions. For example, if the gate balancing resistor, the control circuit pattern, and the temperature sensor are integrated into the Si substrate to form the semiconductor chip 2, the layout freedom can be improved, and miniaturization, high output density, and low cost can be achieved. In addition, the temperature of the semiconductor chip 2 can be detected, and the heat distribution in the semiconductor module can be considered to maximize the effective area of ​​the semiconductor chip 2.

[0041] The insulating substrate 1, the semiconductor chip 2, the lead 8, the main terminal 4, and a part of the signal terminal 7 are sealed (transfer molded) by a sealing resin 9 having excellent mass productivity. The sealing resin 9 is mainly composed of epoxy resin, but is not limited to this, and a thermosetting resin having a desired elastic modulus and adhesion can be used.

[0042] The main terminals 4, 6 and the signal terminals 7a, 7b protrude from the side of the sealing resin 9. The signal terminals 7a, 7b are formed upward. The main terminals 4, 6 can also be formed upward in the same way. The ends of the main terminals 4, 6 and the signal terminals 7a, 7b are connected to the control substrate or external wiring (not shown). The back metal pattern 1c of the insulating substrate 1 is exposed in the central part of the lower surface of the sealing resin 9. The back metal pattern 1c protrudes from the lower surface of the sealing resin by 50 to 200 μm. A step 10 is provided on the outer periphery of the lower surface of the sealing resin 9 of the semiconductor module.

[0043] The exposed surface of the back metal pattern 1c of the insulating substrate 1 is shot peened, for example, by laser irradiation or projection of fine particles of any one of metal, resin and ceramic as the main component. The exposed surface of the back metal pattern 1c after modification and curing by shot peening becomes a characteristic concave-convex shape according to the particle size of the particles projected during the shot peening. Therefore, the surface roughness Ra of the exposed surface of the back metal pattern 1c after modification and curing is 2 to 15 μm, which is greater than the surface roughness of the surface metal pattern 1b.

[0044] Since the exposed surface of the back metal pattern 1c is modified and solidified and plastically deformed, the back metal pattern 1c is convexly warped downward as a whole. The step difference (warping amount) between the end and the center of the exposed surface of the back metal pattern 1c is 50 to 200 μm.

[0045] Figure 4 1 is a cross-sectional view showing the back metal pattern after modification and solidification. The surface layer 1ca from the lower surface of the back metal pattern 1c to a depth of 20 to 30 μm is modified and solidified. The grain size of the metal material in the surface layer 1ca is finer than the grain size of the metal material in the inner 1cb of the back metal pattern 1c that has not been modified and solidified.

[0046] Figure 5 1 is a side view showing a power semiconductor device according to Embodiment 1. In order to cope with high current density, a cooler 12 is bonded to the exposed lower surface and side surface of the back metal pattern 1c of the semiconductor module through a bonding material 11. The cooler 12 is made of, for example, an alloy mainly composed of copper or aluminum. A plurality of cylindrical or prism-shaped fins 13 are formed on the lower surface of the flat plate of the cooler 12. The plurality of fins 13 may be integrated with the flat plate or may be bonded to the flat plate via a bonding material.

[0047] Solder is used as the bonding material 11. When the cooler 12 is made of aluminum or an aluminum alloy, Ni-based or Sn-based plating is applied to the upper surface of the cooler 12 to ensure weldability. In addition, insulating heat dissipation grease such as a thermal interface material may also be used as the bonding material 11. However, soldering further improves the heat dissipation of the semiconductor chip 2 compared to using heat dissipation grease.

[0048] Figure 6 This is a flowchart showing a method for manufacturing the semiconductor module and the power semiconductor device according to the first embodiment. Figure 7 as well as Figure 8 It is a cross-sectional view showing the method for manufacturing the semiconductor module according to the first embodiment. Figure 7 express Figure 6 The state after wire bonding, Figure 8 express Figure 6 The state after molding.

[0049] First, the insulating substrate 1 is placed in a printer, and a paste-like bonding material 3 of a predetermined shape is applied to the upper surface of the surface metal pattern 1b by printing using a metal mask having a thickness of 100 to 200 μm. Next, the insulating substrate 1 coated with the bonding material 3 and the semiconductor chip 2 are placed in a surface mounting machine, and a load is applied to mount the semiconductor chip 2 on the surface metal pattern 1b of the insulating substrate 1 (step S1). Next, these are placed in a reflow furnace, and the solvent is dried in a nitrogen atmosphere, and as shown in FIG. Figure 7 As shown, the lower surface electrode of the semiconductor chip 2 and the surface metal pattern 1 b of the insulating substrate 1 are bonded via a bonding material 3 .

[0050] Next, the main terminal 4 is bonded to the upper surface electrode of the semiconductor chip 2 by the bonding material 5 (step S2). The main terminal 6 is bonded to the surface metal pattern 1b by the bonding material 5. The bonding materials 3 and 5 can also be melted at the same time for bonding. For example, the insulating substrate 1 on which the semiconductor chip 2 is mounted and the main terminal 4 are placed on a lower fixture made of a material with high thermal conductivity, and fixed and held by an upper fixture made of a material with high thermal conductivity. These are placed in a device at 200°C to 300°C and a reducing atmosphere (N2, H2), and molten solder is applied or solid solder is melted. Thus, the main terminal 4 and the semiconductor chip 2 are welded, and the main terminal 6 and the surface metal pattern 1b are welded. Thereafter, it is moved to a cooling workbench for cooling.

[0051] Next, the wire 8 is ultrasonically bonded to the control electrode of the semiconductor chip 2 and the signal terminal 7a to connect the two, and the wire 8 is ultrasonically bonded to the surface metal pattern 1b and the signal terminal 7b to connect the two (step S3).

[0052] Next, the thermosetting sealing resin 9 is heated and made to flow into the heated mold, and transfer molding by pressurization is performed (step S4). For example, components such as the insulating substrate 1 and the semiconductor chip 2 are placed in a mold heated to 150°C to 200°C, and the sealing resin 9 is injected and cured to perform sealing and shape forming. Thus, the insulating substrate 1, the semiconductor chip 2, the lead 8, a part of the main terminals 4 and 6, and a part of the signal terminals 7a and 7b are sealed by the sealing resin 9. The molded product is taken out of the mold and placed in an oven at 150°C to 200°C for post-curing. The molded product has a step 10 formed on the outer periphery of the lower surface of the sealing resin 9 according to the shape of the mold. If the unnecessary terminal portion and the resin burr portion are removed from the molded product by the mold, a Figure 8 structure.

[0053] Next, the exposed surface of the back metal pattern 1c exposed from the lower surface of the sealing resin 9 and the lower surface of the sealing resin 9 are simultaneously shot peened (step S5). During the shot peening, tiny particles are transmitted to these surfaces. By treating the entire lower surface of the back metal pattern 1c at the same time, a uniform treatment can be performed. Thereafter, water washing and drying are performed. The exposed surface of the back metal pattern 1c after the shot peening is modified and solidified, and the back metal pattern 1c is in a convex shape that is warped downward.

[0054] Here, before the shot peening, the lower surface of the sealing resin 9 is coplanar with the exposed surface of the back metal pattern 1c, and the back metal pattern 1c does not protrude from the lower surface of the sealing resin 9. The sealing resin 9 is etched from the lower surface side by the shot peening, so that the back metal pattern 1c protrudes from the lower surface of the sealing resin 9 and the side surface of the back metal pattern 1c is exposed from the sealing resin 9. In addition, in transfer molding, the bottom surface of the mold is usually made flat, so it is difficult to make the back metal pattern 1c protrude from the lower surface of the sealing resin 9 by transfer molding.

[0055] Next, the main terminals 4, 6 and the signal terminals 7a, 7b are plated as needed. The plating is composed of a material with Sn or Ni as the main component. The welding property is improved by plating and corrosion is prevented. The main terminals 4, 6 and the signal terminals 7a, 7b are bent into a shape that is easy to connect to the external terminals (step S6). The semiconductor module involved in this embodiment is manufactured through these steps. The side and lower surface of the back metal pattern 1c of the semiconductor module and the cooler 12 are joined by the bonding material 11 (step S7). The power semiconductor device involved in this embodiment is manufactured through the above steps.

[0056] As described above, in this embodiment, the back metal pattern 1c protrudes from the lower surface of the sealing resin 9 and the side and lower surface of the back metal pattern 1c are exposed from the sealing resin 9. Therefore, the solder contacting the exposed surface of the back metal pattern 1c becomes an ideal welding shape, so the weldability is improved.

[0057] In addition, the exposed surface of the back metal pattern 1c is modified and cured by shot peening and plastically deformed. As a result, the particle size of the metal material of the surface layer 1ca of the back metal pattern 1c becomes finer than the particle size of the metal material of the inner 1cb of the unmodified and cured back metal pattern 1c. For example, in the case where the back metal pattern 1c is copper, if measured by a Vickers hardness test, the hardness of the modified and cured surface layer 1ca is about 83, which is twice the hardness of the unmodified and cured inner 1cb of about 48. The strength is improved by processing and curing the surface layer 1ca of the back metal pattern 1c. Therefore, the resistance to the shear stress generated in the welding part due to long-term repeated thermal stress in the use environment of the power semiconductor device is improved, so that the aggravation of cracks can be suppressed.

[0058] Usually, in order to reduce the contact thermal resistance, the semiconductor module is installed on the cooler via non-metallic heat dissipation grease such as thermal interface material. At this time, if the back of the semiconductor module is concave along the upper side, the thickness of the thermal interface material in the central part becomes thicker. Since the thermal conductivity of the non-metallic thermal interface material is 2 to 3 W / m·K, the thermal resistance of the semiconductor module and the cooler becomes larger. In contrast, in this embodiment, the back metal pattern 1c after shot peening is convex and warped downward. Therefore, it can be installed on the cooler without increasing the thermal resistance. As a result, durability and fatigue strength can be improved.

[0059] In addition, the semiconductor module is composed of a plurality of components with different thermal expansion coefficients. Therefore, the temperature of the semiconductor module changes according to the operation of the semiconductor chip, and thermal stress is generated in each component. As a result, the semiconductor module as a whole is deformed in a warping manner. In the case where a conventional semiconductor module is mounted on a cooler via a thermal interface material, the thermal interface material is gradually pumped out and flows out to the outside due to the above-mentioned warping deformation. As a result, the contact thermal resistance between the semiconductor module and the cooler increases, which promotes the degradation of the semiconductor chip. In contrast, in the present embodiment, the back metal pattern 1c of the insulating substrate 1 is modified and solidified by shot peening, and the strength is improved, so that the warping deformation of the semiconductor module as a whole can be suppressed. As a result, the pumping out of the thermal interface material can be prevented, and the increase in the contact thermal resistance between the semiconductor module and the cooler can be suppressed.

[0060] Therefore, according to this embodiment, the reliability of the joint between the semiconductor module and the cooler can be improved. As a result, a power semiconductor device with a long life and high reliability can be provided.

[0061] In addition, the exposed surface of the back metal pattern 1c after modification and curing is in a concave-convex surface state, and its surface roughness is greater than the surface roughness of the front metal pattern 1b. Therefore, when the exposed surface of the back metal pattern 1c is welded to the cooler 12, the bonding strength is improved by the anchor effect. Thus, the crack cracking can be suppressed from intensifying.

[0062] The thickness of the surface metal pattern 1b and the back metal pattern 1c are 0.2 to 1 mm, respectively, and the thickness of the insulating plate 1a is 0.2 to 1.0 mm. Under this combination of thicknesses, the lower surface of the back metal pattern 1c is plastically deformed in an extended manner by shot peening, so that the back metal pattern 1c is convexly warped downward as a whole. In addition, it is also conceivable that in a previous semiconductor module with an insulating substrate mounted on a base plate, the base plate present on the entire lower surface of the module is shot peened. However, even if the base plate, which is originally rigid and thick at 3 mm to 5 mm, is shot peened, it is impossible to achieve the warpage of 50 to 200 μm required for the semiconductor module.

[0063] The insulating plate 1a of the insulating substrate 1 is made of ceramics such as AlN with high thermal conductivity. Therefore, the heat of the semiconductor chip 2 can be released to the cooler 12 via the insulating plate 1a to suppress the temperature rise of the semiconductor chip 2. As a result, power loss can be suppressed and the switching characteristics, life and reliability of the semiconductor module can be ensured.

[0064] Main terminals 4 and 6 protrude from the side of sealing resin 9, and a step 10 is formed on the outer periphery of the lower surface of sealing resin 9. This ensures a creepage distance between the main terminals of the semiconductor module and the upper surface of cooler 12, and ensures sufficient insulation.

[0065] Implementation Method 2

[0066] Fig. 9 It is a side view showing the semiconductor module according to the second embodiment. Fig.10 1 is a bottom view showing a semiconductor module according to Embodiment 2. A first protrusion 14a and a second protrusion 14b are formed on the lower surface of the sealing resin 9. The first protrusion 14a and the second protrusion 14b are part of the sealing resin 9 and are formed simultaneously when the semiconductor chip 2 and the like are molded. The second protrusion 14b is longer than the first protrusion 14a. The first protrusion 14a is formed adjacent to the back metal pattern 1c. Specifically, two first protrusions 14a are formed in a manner sandwiching the central portion of the long side direction of the back metal pattern 1c. Four first protrusions 14a are formed at the four corners of the back metal pattern 1c.

[0067] Fig.11 as well as Fig.12It is a side view showing a power semiconductor device according to the second embodiment. Fig.11 and Fig.12 It is a side view observed from a direction different by 90°. The back metal pattern 1c after modification and solidification is in a convex shape that is warped downward. Since the back metal pattern 1c is warped in the long side direction, the thickness of the bonding material 11 is small in the central part of the long side direction of the back metal pattern 1c, and increases toward the end. The thickness of the bonding material 11 in the central part only needs to be at least 50 μm. The second protrusion 14b of the semiconductor module contacts the recess 15 formed on the upper surface of the cooler 12, and is guided and engaged therewith.

[0068] Fig.13 This is an enlarged side view of the bonding portion of the power semiconductor device according to Embodiment 2. Not only the lower surface of the back metal pattern 1c but also the side surface is bonded to the bonding material 11, and the bonding material 11 forms a desired fillet. The thickness of the bonding material 11 can be ensured by the first protrusion 14a of the semiconductor module.

[0069] Next, the manufacturing method of the power semiconductor device involved in the present embodiment is described. First, a semiconductor module is manufactured through steps S1 to S6 in the same manner as in the first embodiment. Next, a solid-shaped bonding material 11 is arranged at a predetermined position on the upper surface of the cooler 12. The second protrusion 14b of the semiconductor module is engaged with the recess 15 of the cooler 12 to position the semiconductor module. These are put into a reflow furnace to heat the bonding material 11, and the back metal pattern 1c of the semiconductor module and the cooler 12 are bonded by the bonding material 11. Thereafter, the power semiconductor device is cooled and taken out of the reflow furnace. In addition, as the bonding material 11, a sintered material can also be used instead of solder. The power semiconductor device involved in the present embodiment is manufactured through the above steps.

[0070] As described above, in this embodiment, the thickness of the bonding material 11 composed of heat dissipation grease or solder can be ensured between the back metal pattern 1c and the cooler 12 by the first protrusion 14a. As a result, the semiconductor module can be mounted on the cooler 12 without increasing the thermal resistance. In addition, the crack can be suppressed from being aggravated, and a highly reliable and long-life semiconductor device for electric power can be obtained.

[0071] The semiconductor module can be horizontally mounted on the upper surface of the cooler 12 by the plurality of first protrusions 14a formed on the lower surface of the sealing resin 9. Therefore, the semiconductor module does not tilt, and a desired bonding thickness can be ensured from the center to the end of the back metal pattern 1c.

[0072] The second protrusion 14b of the semiconductor module contacts the recess 15 formed on the upper surface of the cooler 12, and is guided and engaged therewith. Therefore, the positioning of the semiconductor module becomes easy. Fig.11 as well as Fig.12 In the embodiment, only one semiconductor module is mounted on the cooler 12, but usually, as an inverter device, multiple semiconductor modules are mounted on the cooler 12. Therefore, by fitting the second protrusion 14b of each semiconductor module into the recess 15 of the cooler 12, the assembly of multiple semiconductor modules becomes easy, and the productivity is improved. In addition, the second protrusion 14b is formed on the lower surface of the sealing resin 9 at a position closer to the outer peripheral side than the first protrusion 14a, so as not to interfere with the first protrusion 14a for ensuring the thickness of the solder.

[0073] Fig.14 It is a side view showing a modification of the semiconductor module according to the second embodiment. Fig.15 1 is a bottom view showing a modified example of the semiconductor module according to Embodiment 2. Although the first protrusion 14a is formed on the lower surface of the sealing resin 9, the second protrusion 14b is not formed. By forming a plurality of first protrusions 14a on the lower surface of the sealing resin 9, the thickness of the bonding material 11 can be ensured between the back metal pattern 1c and the cooler 12, and the semiconductor module can be mounted horizontally on the upper surface of the cooler 12.

[0074] Implementation 3

[0075] Fig.16 1 is a cross-sectional view showing a power semiconductor device according to Embodiment 3. The interior of the sealing resin 9 is omitted from the illustration. A lower cooler 16 is arranged on the lower surface of the cooler 12 on which the semiconductor module is mounted. A resin case 17 is arranged on the cooler 12 so as to surround the semiconductor module. Screws 19 are fastened to the coolers 12 and 16 through mounting holes 18 formed at the ends of the resin case 17. The main terminal 4 protruding from the side of the sealing resin 9 is supported by the resin case 17. The main terminal 4 and the external terminal 20 overlap flatly and are welded or laser-bonded to each other.

[0076] The coolers 12 and 16 are water-cooled and have excellent heat dissipation. A water-cooling liquid flows inside the lower cooler 16, and the heat from the semiconductor chip 2 can be efficiently released through the multiple fins 13 of the cooler 12. Therefore, the cooling capacity is greatly improved, so it is possible to miniaturize the semiconductor module and the power semiconductor device. In addition, since the heat dissipation of the semiconductor chip 2 is improved, the characteristics are not degraded, the desired power switch can be obtained, and the reliability of the power semiconductor device can be ensured. The other structures and effects are the same as those of embodiments 1 and 2.

[0077] Fig.17This is a cross-sectional view showing a modified example of the power semiconductor device according to the third embodiment. The main terminal 4 and the external terminal 20 are formed upward and are welded or laser-bonded to each other. Fig.16 same.

[0078] Fig.18 This is a flowchart showing a method for manufacturing a semiconductor module and a power semiconductor device according to Embodiment 3. First, a semiconductor module is manufactured through steps S1 to S6 in the same manner as in Embodiment 1.

[0079] Next, a solid bonding material 11 is arranged at a predetermined position on the upper surface of the cooler 12. The second protrusion 14b of the semiconductor module is engaged with the recess 15 of the cooler 12 to position the semiconductor module. These are put into a reflow furnace to heat the bonding material 11, and the back metal pattern 1c of the semiconductor module and the cooler 12 are bonded by the bonding material 11 (step S8). Thereafter, the power semiconductor device is cooled and taken out of the reflow furnace. Solder may be used as the bonding material 11 instead of the sintered material.

[0080] Next, the resin case 17 is arranged on the cooler 12 in such a manner as to surround the semiconductor module and support the main terminal 4 from below. The lower cooler 16 is arranged on the lower surface of the cooler 12. The screws 19 are fastened to the coolers 12 and 16 through the mounting holes 18 formed in the resin case 17 (step S9). In addition, a sealing material may be inserted between the cooler 12 and the lower cooler 16, or the two may be bonded via an adhesive.

[0081] Next, the main terminal 4 and the external terminal 20 are welded or laser-bonded to each other (step S10). The main terminal 4 and the external terminal 20 may be laser-bonded via solder. The power semiconductor device according to the present embodiment is manufactured through the above steps.

[0082] Implementation 4

[0083] Fig.19 1 is a cross-sectional view showing a power semiconductor device according to Embodiment 4. However, the interior of the sealing resin 9 is omitted from the illustration.

[0084] As in the third embodiment, the semiconductor module is bonded to the upper surface of the cooler 21 by the bonding material 11. The second protrusion 14b of the semiconductor module is engaged with the recess 15 formed on the upper surface of the cooler 21 to position the semiconductor module. The thickness of the bonding material 11 can be ensured by the first protrusion 14a. The resin case 17 is arranged in a manner to surround the semiconductor module and support the main terminal 4 from below. The screw 19 is fastened to the cooler 21 through the mounting hole 18 formed in the resin case 17. The main terminal 4 protruding from the side of the sealing resin 9 is supported by the resin case 17. The main terminal 4 and the external terminal 20 overlap flatly and are welded or laser-bonded to each other.

[0085] The cooler 21 of this embodiment is formed by integrating the coolers 12 and 16 of the third embodiment. The cooler 21 is made of, for example, an alloy mainly composed of copper or aluminum. The cooler 21 is water-cooled and has excellent heat dissipation. A water-cooling liquid flows inside the cooler 21, and the heat from the semiconductor chip 2 can be efficiently released through the plurality of fins 13 formed inside the cooler 21.

[0086] Fig. 20 This is a cross-sectional view showing a modified example of the power semiconductor device according to the fourth embodiment. The main terminal 4 and the external terminal 20 are formed upward and are welded or laser-bonded to each other. Fig.19 same.

[0087] Fig.21 This is a flowchart showing a method for manufacturing a semiconductor module and a power semiconductor device according to Embodiment 4. First, a semiconductor module is manufactured through steps S1 to S6 in the same manner as in Embodiment 1.

[0088] Next, a solid bonding material 11 is arranged at a predetermined position on the upper surface of the cooler 21. The semiconductor module is positioned by fitting the second protrusion 14b of the semiconductor module into the recess 15 formed on the upper surface of the cooler 21. The resin housing 17 is arranged on the cooler 21 in such a manner as to surround the semiconductor module and support the main terminal 4 from below. The screw 19 is fastened to the cooler 21 through the mounting hole 18 formed in the resin housing 17. These are put into a reflow furnace to heat the bonding material 11, and the back metal pattern 1c of the semiconductor module and the cooler 21 are bonded by the bonding material 11 (step S11). Thereafter, the power semiconductor device is cooled and taken out of the reflow furnace. In particular, as the bonding material 11, a sintered material can also be used instead of solder.

[0089] Next, the main terminals 4 and 6 and the external terminal 20 are welded or laser-bonded to each other (step S12). Alternatively, the main terminal 4 and the external terminal 20 may be laser-bonded via solder. The power semiconductor device according to the present embodiment is manufactured through the above steps.

[0090] In addition, the semiconductor chip 2 is not limited to being formed by silicon, and can also be formed by a wide bandgap semiconductor with a larger bandgap than silicon. Wide bandgap semiconductors are, for example, silicon carbide, gallium nitride-based materials, or diamond. Semiconductor chips formed by such wide bandgap semiconductors can be miniaturized because of their high voltage resistance and allowable current density. By using the miniaturized semiconductor chip, a semiconductor device assembled with the semiconductor chip can also be miniaturized and highly integrated. In addition, since the semiconductor chip has high heat resistance, the heat dissipation fins of the radiator can be miniaturized, and the water cooling part can be air-cooled, so the semiconductor device can be further miniaturized. In addition, since the power loss of the semiconductor chip is low and the efficiency is high, the efficiency of the semiconductor device can be achieved.

[0091] Implementation method 5

[0092] This embodiment applies the power semiconductor devices according to the above-mentioned Embodiments 1 to 4 to a power conversion device. Although the present disclosure is not limited to a specific power conversion device, the case where the present disclosure is applied to a three-phase inverter will be described below as Embodiment 5.

[0093] Fig. 22 1 is a block diagram showing the structure of a power conversion system to which the power conversion device according to Embodiment 5 is applied. The power conversion system includes a power supply 100, a power conversion device 200, and a load 300. The power supply 100 is a DC power supply, and supplies DC power to the power conversion device 200. The power supply 100 can be composed of various components, for example, it can be composed of a DC system, a solar cell, a storage battery, or a rectifier circuit or an AC / DC converter connected to an AC system. In addition, the power supply 100 can also be composed of a DC / DC converter that converts the DC power output from the DC system into a predetermined power.

[0094] The power conversion device 200 is a three-phase inverter connected between the power source 100 and the load 300, converts the DC power supplied from the power source 100 into AC power, and supplies the AC power to the load 300. The power conversion device 200 includes: a main conversion circuit 201 that converts the DC power into AC power and outputs it; and a control circuit 203 that outputs a control signal to control the main conversion circuit 201 to the main conversion circuit 201.

[0095] The load 300 is a three-phase motor driven by the AC power supplied from the power conversion device 200. The load 300 is not limited to a specific use, but is a motor mounted on various electrical devices, such as a hybrid vehicle, an electric vehicle, a railway vehicle, an elevator, or a motor for an air conditioner.

[0096] The power conversion device 200 is described in detail below. The main conversion circuit 201 includes a switching element and a freewheeling diode (not shown), and converts the DC power supplied from the power supply 100 into AC power by switching the switching element, and supplies it to the load 300. Although there are many specific circuit structures of the main conversion circuit 201, the main conversion circuit 201 involved in this embodiment is a two-stage three-phase full-bridge circuit, which can be composed of six switching elements and six freewheeling diodes connected in reverse parallel to each switching element. Each switching element and each freewheeling diode of the main conversion circuit 201 is composed of a semiconductor device 202 equivalent to any one of the above-mentioned embodiments 1 to 4. The six switching elements are connected in series to form upper and lower branches, and each upper and lower branch constitutes each phase (U phase, V phase, W phase) of the full-bridge circuit. In addition, the output terminals of each upper and lower branch, that is, the three output terminals of the main conversion circuit 201, are connected to the load 300.

[0097] In addition, although the main conversion circuit 201 is provided with a driving circuit (not shown) for driving each switching element, the driving circuit may be built into the semiconductor device 202, or may be a structure that is provided with a driving circuit separately from the semiconductor device 202. The driving circuit generates a driving signal for driving the switching element of the main conversion circuit 201, and supplies it to the control electrode of the switching element of the main conversion circuit 201. Specifically, according to the control signal from the control circuit 203 described later, a driving signal for turning on the switching element and a driving signal for turning off the switching element are output to the control electrode of each switching element. When the switching element is maintained in the on state, the driving signal is a voltage signal (on signal) above the threshold voltage of the switching element, and when the switching element is maintained in the off state, the driving signal becomes a voltage signal (off signal) below the threshold voltage of the switching element.

[0098] The control circuit 203 controls the switch elements of the main conversion circuit 201 in such a manner that the desired power is supplied to the load 300. Specifically, the time (on time) that each switch element of the main conversion circuit 201 should be in the on state is calculated based on the power to 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 switch element according to the voltage to be output. Then, a control instruction (control signal) is output to the drive circuit of the main conversion circuit 201 in such a manner that an on signal is output to the switch element that should be in the on state and an off signal is output to the switch element that should be in the off state at each moment. The drive circuit outputs an on signal or an off signal as a drive signal to the control electrode of each switch element according to the control signal.

[0099] In the power conversion device according to the present embodiment, since the power semiconductor device according to Embodiments 1 to 4 is applied as the semiconductor device 202 , the reliability of the junction between the semiconductor module and the cooler can be improved.

[0100] Although the present disclosure is applied to a two-stage three-phase inverter in the present embodiment, the present disclosure is not limited thereto, but can be applied to various power conversion devices. Although the present disclosure is a two-stage power conversion device, it can also be a three-stage or multi-stage power conversion device, and the present disclosure can also be applied to a single-phase inverter when power is supplied to a single-phase load. In addition, the present disclosure can also be applied to a DC / DC converter or an AC / DC converter when power is supplied to a component such as a DC load.

[0101] In addition, the power conversion device disclosed in the present invention is not limited to the case where the above-mentioned load is an electric motor. For example, it can also be used as a power supply device for an electric discharge machine, a laser processing machine, an induction heating cooker, or a contactless power supply system. It can also be used as a power conditioner for a solar power generation system or a power storage system.

[0102] Although preferred embodiments have been described in detail above, the present invention is not limited to the above embodiments, and various modifications and substitutions can be made to the above embodiments without departing from the scope described in the claims.

[0103] (Supplementary Note 1) A semiconductor module, characterized in that:

[0104] The semiconductor module has:

[0105] An insulating substrate having an insulating plate, a surface metal pattern formed on a surface of the insulating plate, and a back metal pattern formed on a back surface of the insulating plate;

[0106] A semiconductor chip mounted on the surface metal pattern of the insulating substrate;

[0107] A main terminal connected to the main electrode on the upper surface of the semiconductor chip;

[0108] A signal terminal connected to the control electrode on the upper surface of the semiconductor chip through a lead wire; and

[0109] a sealing resin that seals the insulating substrate, the semiconductor chip, the leads, a portion of the main terminals, and a portion of the signal terminals,

[0110] The back metal pattern protrudes from the lower surface of the sealing resin and the side surface and the lower surface of the back metal pattern are exposed from the sealing resin.

[0111] The exposed surface of the back metal pattern is modified and solidified.

[0112] The rear metal pattern has a convex shape that is warped downward.

[0113] (Supplementary Note 2) The semiconductor module according to Supplementary Note 1, characterized in that:

[0114] The particle size of the metal material on the surface layer of the rear metal pattern after modification and solidification is finer than the particle size of the metal material inside the rear metal pattern before modification and solidification.

[0115] (Supplementary Note 3) The semiconductor module according to Supplementary Note 2, characterized in that:

[0116] The surface roughness of the exposed surface of the rear metal pattern after modification and curing is greater than the surface roughness of the front metal pattern.

[0117] (Supplementary Note 4) The semiconductor module according to any one of Supplementary Notes 1 to 3, characterized in that:

[0118] The thickness of the surface metal pattern and the back metal pattern are respectively 0.2-1 mm, and the thickness of the insulating plate is 0.2-1.0 mm.

[0119] (Supplementary Note 5) The semiconductor module according to any one of Supplementary Notes 1 to 4, characterized in that:

[0120] The insulating plate is made of ceramic.

[0121] (Supplementary Note 6) The semiconductor module according to any one of Supplementary Notes 1 to 5, characterized in that:

[0122] The main terminal protrudes from the side surface of the sealing resin.

[0123] A step is formed on an outer peripheral portion of a lower surface of the sealing resin.

[0124] (Supplementary Note 7) The semiconductor module according to any one of Supplementary Notes 1 to 6, characterized in that:

[0125] A protrusion is formed on the lower surface of the sealing resin.

[0126] (Supplementary Note 8) The semiconductor module according to Supplementary Note 7, characterized in that:

[0127] The protrusions include a first protrusion and a second protrusion that is longer than the first protrusion.

[0128] (Supplementary Note 9) The semiconductor module according to Supplementary Note 8, characterized in that

[0129] The first protrusion is formed to be adjacent to the back metal pattern.

[0130] The second protrusion is formed on the lower surface of the sealing resin at an outer peripheral side than the first protrusion.

[0131] (Supplementary Note 10) The semiconductor module according to any one of Supplementary Notes 1 to 9, characterized in that:

[0132] The semiconductor chip is formed of a wide bandgap semiconductor.

[0133] (Supplementary Note 11) A semiconductor device for electric power, characterized in that:

[0134] The above-mentioned power semiconductor device comprises:

[0135] The semiconductor module according to any one of Supplementary Notes 1 to 10; and

[0136] The cooler is bonded to the side surfaces and the bottom surface of the back metal pattern of the semiconductor module via a bonding material.

[0137] (Supplementary Note 12) A semiconductor device for electric power, characterized in that:

[0138] The above-mentioned power semiconductor device comprises:

[0139] The semiconductor module described in Supplementary Note 7; and

[0140] a cooler bonded to the side and bottom surfaces of the back metal pattern of the semiconductor module via a bonding material;

[0141] A recess is formed on the upper surface of the cooler.

[0142] The protrusion of the semiconductor module is fitted into the recess.

[0143] (Supplementary Note 13) A semiconductor device for electric power, characterized in that:

[0144] The above-mentioned power semiconductor device comprises:

[0145] The semiconductor module described in Supplementary Note 8; and

[0146] a cooler bonded to the side and bottom surfaces of the back metal pattern of the semiconductor module via a bonding material;

[0147] A recess is formed on the upper surface of the cooler.

[0148] The second protrusion is fitted into the recessed portion.

[0149] (Supplementary Note 14) The power semiconductor device according to any one of Supplementary Notes 11 to 13, characterized in that:

[0150] A plurality of fins are formed on the lower surface of the cooler.

[0151] (Supplementary Note 15) The power semiconductor device according to any one of Supplementary Notes 11 to 14, characterized in that:

[0152] The above cooler is water-cooled.

[0153] (Supplementary Note 16) A method for manufacturing a semiconductor module, characterized in that:

[0154] The method for manufacturing the semiconductor module comprises:

[0155] A step of mounting a semiconductor chip on the surface metal pattern of an insulating substrate having an insulating plate, a surface metal pattern formed on the surface of the insulating plate, and a back metal pattern formed on the back of the insulating plate;

[0156] A step of connecting a main terminal to a main electrode on the upper surface of the semiconductor chip;

[0157] The step of connecting the signal terminal to the control electrode on the upper surface of the semiconductor chip through a lead wire;

[0158] a step of sealing the insulating substrate, the semiconductor chip, the leads, a part of the main terminals, and a part of the signal terminals with a sealing resin; and

[0159] a step of performing shot peening by simultaneously projecting particles onto an exposed surface of the back metal pattern exposed from the lower surface of the sealing resin and the lower surface of the sealing resin;

[0160] Before the shot peening, the lower surface of the back metal pattern is coplanar with the lower surface of the sealing resin.

[0161] After the shot peening, the back metal pattern protrudes from the lower surface of the sealing resin and the side surface of the back metal pattern is exposed from the sealing resin.

[0162] The exposed surface of the back metal pattern after shot peening is modified and solidified.

[0163] The back metal pattern after the shot peening process has a convex shape that is warped downward.

[0164] (Supplementary Note 17) A method for manufacturing a semiconductor device for electric power, characterized in that:

[0165] The method for manufacturing the above-mentioned semiconductor device for electric power comprises:

[0166] A process for manufacturing a semiconductor module by the method described in Supplementary Note 16; and

[0167] The step of bonding the side surface and the bottom surface of the back metal pattern of the semiconductor module to a cooler via a bonding material.

[0168] (Supplementary Note 18) The method for manufacturing a power semiconductor device according to Supplementary Note 17, characterized by comprising:

[0169] The step of disposing a resin case on the cooler so as to surround the semiconductor module, disposing a lower cooler on a lower surface of the cooler, and fastening screws to the cooler and the lower cooler through mounting holes formed in the resin case.

[0170] (Supplementary Note 19) The method for manufacturing a power semiconductor device according to Supplementary Note 17, characterized by comprising:

[0171] A step of disposing a resin case on the cooler so as to surround the semiconductor module, and fastening the resin case to the cooler by passing screws through mounting holes formed in the resin case.

[0172] (Supplementary Note 20) The method for manufacturing a power semiconductor device according to any one of Supplementary Notes 17 to 19, characterized in that:

[0173] A protrusion is formed on the lower surface of the sealing resin, a recess is formed on the upper surface of the cooler, and the protrusion is fitted into the recess.

[0174] (Supplementary Note 21) A power conversion device, characterized in that:

[0175] The above-mentioned power conversion device comprises:

[0176] A main conversion circuit comprising a power semiconductor device according to any one of Supplementary Notes 11 to 15, and converting input power and outputting the converted power; and

[0177] The control circuit outputs a control signal for controlling the main conversion circuit to the main conversion circuit.

Claims

1. A semiconductor module, characterized in that: The semiconductor module comprises: An insulating substrate having an insulating plate, a surface metal pattern formed on a surface of the insulating plate, and a back metal pattern formed on a back surface of the insulating plate; A semiconductor chip mounted on the surface metal pattern of the insulating substrate; A main terminal connected to a main electrode on the upper surface of the semiconductor chip; A signal terminal connected to the control electrode on the upper surface of the semiconductor chip through a lead wire; as well as a sealing resin that seals the insulating substrate, the semiconductor chip, the leads, a portion of the main terminals, and a portion of the signal terminals, The back metal pattern protrudes from the lower surface of the sealing resin and the side surface and the lower surface of the back metal pattern are exposed from the sealing resin, The exposed surface of the back metal pattern is modified and solidified, The rear metal pattern has a convex shape that is warped downward.

2. The semiconductor module according to claim 1, characterized in that The particle size of the metal material on the surface layer of the rear metal pattern after modification and solidification is finer than the particle size of the metal material inside the rear metal pattern after modification and solidification.

3. The semiconductor module according to claim 2, characterized in that The surface roughness of the exposed surface of the rear metal pattern after modification and curing is greater than the surface roughness of the front metal pattern.

4. The semiconductor module according to any one of claims 1 to 3, characterized in that The thickness of the surface metal pattern and the back metal pattern are respectively 0.2-1 mm, and the thickness of the insulating plate is 0.2-1.0 mm.

5. The semiconductor module according to any one of claims 1 to 3, characterized in that: The insulating plate is made of ceramic.

6. The semiconductor module according to any one of claims 1 to 3, characterized in that: The main terminal protrudes from the side surface of the sealing resin, A step is formed on an outer peripheral portion of a lower surface of the sealing resin.

7. The semiconductor module according to any one of claims 1 to 3, characterized in that: A protrusion is formed on the lower surface of the sealing resin.

8. The semiconductor module according to claim 7, characterized in that The protrusion includes a first protrusion and a second protrusion longer than the first protrusion.

9. The semiconductor module according to claim 8, characterized in that The first protrusion is formed to be adjacent to the back metal pattern, The second protrusion is formed on the lower surface of the sealing resin at an outer peripheral side of the first protrusion.

10. The semiconductor module according to any one of claims 1 to 3, characterized in that The semiconductor chip is formed of a wide bandgap semiconductor.

11. A semiconductor device for electric power, characterized in that: The power semiconductor device comprises: The semiconductor module according to any one of claims 1 to 3; and The cooler is bonded to the side surfaces and the bottom surface of the back metal pattern of the semiconductor module via a bonding material.

12. A semiconductor device for electric power, characterized in that: The power semiconductor device comprises: The semiconductor module according to claim 7; and a cooler bonded to the side surface and the bottom surface of the back metal pattern of the semiconductor module through a bonding material, A recess is formed on the upper surface of the cooler. The protrusion of the semiconductor module is fitted into the recess.

13. A semiconductor device for electric power, characterized in that: The power semiconductor device comprises: The semiconductor module according to claim 8; and a cooler bonded to the side surface and the bottom surface of the back metal pattern of the semiconductor module through a bonding material, A recess is formed on the upper surface of the cooler. The second protrusion is fitted into the recess.

14. The power semiconductor device according to claim 11, wherein: A plurality of fins are formed on a lower surface of the cooler.

15. The power semiconductor device according to claim 11, wherein: The cooler is water-cooled.

16. A method for manufacturing a semiconductor module, characterized in that: The method for manufacturing the semiconductor module comprises: A step of mounting a semiconductor chip on a surface metal pattern of an insulating substrate having an insulating plate, a surface metal pattern formed on a surface of the insulating plate, and a back metal pattern formed on a back surface of the insulating plate; A step of connecting a main terminal to a main electrode on the upper surface of the semiconductor chip; A step of connecting a signal terminal to a control electrode on the upper surface of the semiconductor chip through a lead wire; a step of sealing the insulating substrate, the semiconductor chip, the leads, a part of the main terminals, and a part of the signal terminals with a sealing resin; and a step of performing shot peening by simultaneously projecting particles onto an exposed surface of the back metal pattern exposed from the lower surface of the sealing resin and the lower surface of the sealing resin; Before the shot peening, the lower surface of the back metal pattern is coplanar with the lower surface of the sealing resin. After the shot peening, the back metal pattern protrudes from the lower surface of the sealing resin and the side surface of the back metal pattern is exposed from the sealing resin. The exposed surface of the back metal pattern after shot peening is modified and solidified. The back metal pattern after the shot peening process has a convex shape that is warped downward.

17. A method for manufacturing a semiconductor device for electric power, characterized in that: The method for manufacturing a power semiconductor device comprises: A process for manufacturing a semiconductor module by the method according to claim 16; and The step of bonding the side surface and the bottom surface of the back metal pattern of the semiconductor module to a cooler by using a bonding material.

18. The method for manufacturing a power semiconductor device according to claim 17, wherein: have: The step of disposing a resin case on the cooler so as to surround the semiconductor module, disposing a lower cooler on a lower surface of the cooler, and fastening screws to the cooler and the lower cooler through mounting holes formed in the resin case.

19. The method for manufacturing a power semiconductor device according to claim 17, wherein: have: A step of disposing a resin case on the cooler so as to surround the semiconductor module, and fastening the resin case to the cooler by passing screws through mounting holes formed in the resin case.

20. The method for manufacturing a power semiconductor device according to any one of claims 17 to 19, characterized in that: A protrusion is formed on the lower surface of the sealing resin, a recess is formed on the upper surface of the cooler, and the protrusion is fitted into the recess.

21. A power conversion device, characterized in that: The power conversion device comprises: A main conversion circuit, comprising the power semiconductor device according to claim 11, which converts input power and outputs the converted power; and The control circuit outputs a control signal for controlling the main conversion circuit to the main conversion circuit.

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