Semiconductor device and method for manufacturing semiconductor device

Abstract

The purpose is to provide a semiconductor device with improved bonding reliability between a lead portion and a semiconductor element. The semiconductor device includes a semiconductor element and a lead portion. The semiconductor element is mounted on a circuit pattern provided on an insulating substrate. The lead portion has a plate-like shape and is bonded to the semiconductor element via a first bonding material. The lead portion includes a lead body and a bonding component. The lead body includes an opening portion provided corresponding to a mounting position of the semiconductor element. The bonding component is provided on the semiconductor element in the opening portion. The lower surface of the bonding component is bonded to the semiconductor element via the first bonding material, and the outer periphery of the bonding component is bonded to the inner periphery of the opening portion via a second bonding material.

Description

Technical Field

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

[0002] As a structure in which a lead frame is directly bonded to a semiconductor element, a semiconductor device having a DLB (Direct Lead Bonding) structure is known. In such a semiconductor device, a gap between the lead frame and the semiconductor element affects the bonding state, thus affecting the reliability of the semiconductor device.

[0003] Patent document 1 discloses a structure in which, even if the height of the bonding point between the external lead and the metal sheet is uneven due to deformation such as warping or twisting of the lead frame, the metal sheet with a small spring constant can absorb the fluctuation and make the load uniform, thereby keeping the solder amount constant.

[0004] Patent Document 1: Japanese Patent Application Laid-Open No. 53-015762 Summary of the invention

[0005] In the case of a semiconductor device with a DLB structure, the gap between the lead portion and the semiconductor element is affected by the warping of the insulating circuit substrate and the base plate arranged below the semiconductor element when the two are joined, that is, when heated. The warping is caused by the difference in linear expansion coefficients of the components. If the warping becomes larger during joining, a gap is generated between the lead portion and the semiconductor element or the joining area between the two is insufficient. As a result, the reliability of the joint between the lead portion and the semiconductor element is reduced.

[0006] The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a semiconductor device having improved bonding reliability between a lead portion and a semiconductor element.

[0007] The semiconductor device of the present invention includes a semiconductor element and a lead portion. The semiconductor element is mounted on a circuit pattern provided on an insulating substrate. The lead portion has a plate-like shape and is bonded to the semiconductor element via a first bonding material. The lead portion includes a lead body and a bonding component. The lead body includes an opening portion provided corresponding to the mounting position of the semiconductor element. The bonding component is provided on the semiconductor element in the opening portion. The lower surface of the bonding component is bonded to the semiconductor element via the first bonding material, and the outer periphery of the bonding component is bonded to the inner periphery of the opening portion via a second bonding material.

[0008] Effects of the Invention

[0009] According to the present invention, it is possible to provide a semiconductor device having improved bonding reliability between a lead portion and a semiconductor element.

[0010] The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description and accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a plan view showing the structure of the semiconductor device in the first embodiment.

[0012] Figure 2 It is a cross-sectional view showing the structure of the semiconductor device in the first embodiment.

[0013] Figure 3 This is a flowchart showing the method for manufacturing the semiconductor device in the first embodiment.

[0014] Figure 4 This is a plan view showing the structure of a semiconductor device in the middle of manufacturing in the first embodiment.

[0015] Figure 5 This is a cross-sectional view showing the structure of a semiconductor device in the middle of manufacturing in the first embodiment.

[0016] Figure 6 This is a cross-sectional view showing the state of the semiconductor device at a high temperature in the method for manufacturing the semiconductor device according to the first embodiment.

[0017] Figure 7 This is a cross-sectional view showing the state of the semiconductor device at a high temperature in the method for manufacturing the semiconductor device according to the second embodiment.

[0018] Figure 8 It is a cross-sectional view showing an opening portion of a lead body and a bonding member before bonding in the third embodiment.

[0019] Fig. 9 It is a cross-sectional view showing the opening portion of the lead body and the bonding member after bonding in the third embodiment.

[0020] Fig.10 It is a cross-sectional view showing the opening portion of the lead body and the bonding component before bonding in the fourth embodiment.

[0021] Fig.11 It is a cross-sectional view showing the opening portion of the lead body and the bonding component before bonding in the fifth embodiment.

[0022] Fig.12 This is a cross-sectional view showing the state of the semiconductor device at a high temperature in the method for manufacturing the semiconductor device according to the seventh embodiment. DETAILED DESCRIPTION

[0023] <Implementation method 1>

[0024] Figure 1It is a plan view showing the structure of the semiconductor device in the first embodiment. Figure 2 is a cross-sectional view showing the structure of the semiconductor device in Embodiment 1, showing Figure 1 The cross section at A-A' in FIG.

[0025] The semiconductor device includes a base plate 2 , an insulating circuit substrate 4 , a case 5 , a lead portion 8 , and a semiconductor element 10 .

[0026] The base plate 2 has a plate-like shape with a flat front surface and a flat back surface, and is formed of, for example, Cu, Al, or AlSiC. The back surface of the base plate 2 may be provided with pillar fins or the like for improving the cooling performance of the semiconductor device.

[0027] The insulating circuit substrate 4 includes an insulating substrate 4A and circuit patterns 4B and 4C. The circuit patterns 4B and 4C are formed on the surface and back of the insulating substrate 4A, respectively. The back of the insulating circuit substrate 4 is fixed to the surface of the base plate 2 by the solder 3. Here, the circuit pattern 4C on the back side is bonded to the base plate 2. The circuit pattern 4B on the front side constitutes an electric circuit, and therefore, the coverage rate of the insulating substrate 4A is lower than that of the circuit pattern 4C on the back side. The insulating substrate 4A is formed of, for example, Al2O3, AlN, and Si3N4. The circuit pattern 4B on the front side and the circuit pattern 4C on the back side are formed of, for example, Al and Cu.

[0028] The semiconductor element 10 is mounted on the circuit pattern 4B on the surface side. In the first embodiment, a plurality of semiconductor elements 10 are fixed on the insulating circuit substrate 4 via solder 9. The semiconductor element 10 is formed of, for example, a semiconductor such as Si or a so-called wide bandgap semiconductor such as SiC, GaN, etc. The semiconductor element 10 is, for example, an IGBT (Insulated Gate Bipolar Transistor), a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), a Schottky barrier diode, etc. The semiconductor element 10 is, for example, a semiconductor element for electric power (power semiconductor element).

[0029] The lead portion 8 is a plate-like conductor and includes a lead body 8A and a bonding member 8B.

[0030] The lead body 8A includes an opening 8C provided corresponding to the mounting position of the semiconductor element 10. The opening 8C is a through hole. The inner periphery of the opening 8C in the first embodiment is provided with a first step 81 protruding toward the inner side of the opening 8C. The back surface of the first step 81 is coplanar with the back surface of the lead body 8A. Therefore, the size of the front side of the opening 8C is larger than that of the back side. The lead body 8A is formed of, for example, Cu or Al.

[0031] The bonding component 8B is provided in the opening 8C of the lead body 8A and on the semiconductor element 10. The lower surface of the bonding component 8B is bonded to the surface of the semiconductor element 10 by the first bonding material 11. The first bonding material 11 is, for example, solder. In addition, the bonding component 8B in the first embodiment includes a second step portion 82 protruding to the outside of the outer periphery. The upper surface of the second step portion 82 is coplanar with the upper surface of the bonding component 8B. Therefore, the outer shape of the upper surface side of the bonding component 8B is larger than the lower surface side. In addition, the outer shape of the bonding component 8B including the second step portion 82 is larger than the outer shape of the opening 8C including the first step portion 81 of the lead body 8A. The first step portion 81 of the lead body 8A and the second step portion 82 of the bonding component 8B are arranged opposite to each other. The first step portion 81 and the second step portion 82 are bonded to each other by the second bonding material 12. That is, the outer periphery of the bonding component 8B is bonded to the inner periphery of the opening 8C by the second bonding material 12. The second bonding material 12 is, for example, solder. The bonding member 8B is formed of, for example, Cu or Al.

[0032] The housing 5 accommodates the insulating substrate 4A on which the semiconductor element 10 is mounted, and holds both ends of the lead portion 8. The housing 5 has, for example, a frame shape. The back surface of the housing 5 is fixed to the outer periphery of the surface of the base plate 2 by an adhesive material or the like. The housing 5 is formed of, for example, PPS (Polyphenylenesulfide).

[0033] Figure 3 This is a flowchart showing the method for manufacturing the semiconductor device in the first embodiment.

[0034] In step S1, the semiconductor element 10 mounted on the circuit pattern 4B on the front surface side of the insulating substrate 4A is prepared. At this time, the solder 9 before joining is formed of, for example, a cream solder or a plate solder.

[0035] In step S2 , the lead body 8A is placed so that the opening 8C of the lead body 8A corresponds to the mounting position of the semiconductor element 10 .

[0036] In step S3 , the bonding member 8B is placed on the semiconductor element 10 in the opening 8C. Figure 4 It is a top view showing the structure of the semiconductor device in step S3. Figure 5 is a cross-sectional view showing the structure of the semiconductor device in step S3, showing Figure 4 The cross section at BB' in FIG. 8 is shown. At this time, the first bonding material and the second bonding material before bonding are formed of, for example, a solder paste or a solder plate. Here, the second bonding material before bonding is applied to the upper surface of the bonding component 8B.

[0037] In step S4 , semiconductor element 10 and lead portion 8 are heated. Figure 6 FIG. 1 is a cross-sectional view showing the state of the semiconductor device at high temperature in step S4. Since the linear expansion coefficients of the components are different, warping occurs during bonding. For example, a semiconductor device such as Figure 6 As shown, the lead 8 is warped into a downward convex shape. Here, the state in which the structure from the semiconductor element 10 to the base plate 2 is warped into a downward convex shape but the lead portion 8 held by the housing 5 is not warped is described as an example. Due to the occurrence of such warping, the position of the semiconductor element 10 relative to the lead portion 8 in the z direction changes. During heating, the bonding component 8B is not fixed to the lead body 8A but is movable, so it moves in the direction of the semiconductor element 10 following the warping, that is, the bonding component 8B moves along the z direction following the displacement of the semiconductor element 10. Therefore, the bonding component 8B is in close contact with the semiconductor element 10 via the first bonding material. In addition, the second bonding material 12 on the upper surface of the bonding component 8B melts and flows into the outer periphery of the bonding component 8B and the inner periphery of the opening 8C of the lead body 8A. As a result, the outer periphery of the bonding component 8B and the inner periphery of the opening 8C are in close contact via the second bonding material 12.

[0038] The state of the semiconductor device after cooling is as follows Figure 2 As shown. The structure from the semiconductor element 10 to the base plate 2 is restored to a flat state. The lead portion 8 is warped into a shape that is convex upward, but since the lead portion 8 is a thin plate, such deformation is permissible. No gap is generated between the lower surface of the bonding component 8B and the semiconductor element 10, and the bonding component 8B is stably bonded to the semiconductor element 10. In addition, the outer periphery of the bonding component 8B is also stably bonded to the inner periphery of the opening 8C of the lead body 8A.

[0039] In summary, the semiconductor device in Embodiment 1 includes a semiconductor element 10 and a lead portion 8. The semiconductor element 10 is mounted on a circuit pattern 4B provided on an insulating substrate 4A. The lead portion 8 has a plate-like shape and is bonded to the semiconductor element 10 via a first bonding material 11. The lead portion 8 includes a lead body 8A and a bonding component 8B. The lead body 8A includes an opening 8C provided corresponding to the mounting position of the semiconductor element 10. The bonding component 8B is provided on the semiconductor element 10 in the opening 8C. The lower surface of the bonding component 8B is bonded to the semiconductor element 10 via the first bonding material 11, and the outer periphery of the bonding component 8B is bonded to the inner periphery of the opening 8C via a second bonding material 12.

[0040] Furthermore, the semiconductor device in the first embodiment includes a housing 5 . The housing 5 accommodates the insulating substrate 4A on which the semiconductor element 10 is mounted, and holds both ends of the lead portion 8 .

[0041] According to such a structure, the bonding reliability between the lead portion 8 and the semiconductor element 10 is improved. In particular, when a plurality of semiconductor elements 10 are bonded to the long lead portion 8, the displacement amount in the z direction of the semiconductor element 10 arranged on the central side of the lead portion 8 during heating is large. Even in such a situation, since the bonding member 8B follows the warping, the semiconductor element 10 and the lead portion 8 are stably bonded, and a sufficient bonding area is ensured. In addition, the assemblability of the semiconductor device is also improved.

[0042] In addition, in Embodiment 1, a semiconductor device in which three semiconductor elements 10 are bonded to one lead portion 8 is shown as an example, but the present invention is not limited to such a structure. The semiconductor device may also include a structure in which one or two semiconductor elements are bonded to one lead portion 8, or a structure in which four or more semiconductor elements are bonded to one lead portion 8.

[0043] In addition, the method for manufacturing a semiconductor device in the first embodiment includes a step of preparing a semiconductor element 10 mounted on a circuit pattern 4B provided on an insulating substrate 4A and a step of bonding a lead portion 8 having a plate-like shape to the semiconductor element 10 via a first bonding material 11. The step of bonding the lead portion 8 to the semiconductor element 10 includes the following steps: placing a lead body 8A including an opening 8C in a manner such that the opening 8C corresponds to a mounting position of the semiconductor element 10; placing a bonding member 8B on the semiconductor element 10 in the opening 8C; and heating the semiconductor element 10 and the lead portion 8 so that the lower surface of the bonding member 8B is bonded to the semiconductor element 10 via the first bonding material 11, and the outer periphery of the bonding member 8B is bonded to the inner periphery of the opening 8C via a second bonding material 12.

[0044] Such a method for manufacturing a semiconductor device can manufacture a semiconductor device with improved bonding reliability between the lead portion 8 and the semiconductor element 10. In the case where the bonding between the lead portion 8 and the semiconductor element 10 is performed by a dripping method based on molten solder, the influence of the warping of the semiconductor device generated when the lead portion 8 and the semiconductor element 10 are bonded does not become a problem. This is because the dripping method can supply a sufficient amount of solder. However, in order to reduce the number of manufacturing processes, it is preferred that the bonding between the base plate 2 and the insulating circuit substrate 4, the bonding between the insulating circuit substrate 4 and the semiconductor element 10, and the bonding between the semiconductor element 10 and the lead portion 8 can be performed simultaneously. For this purpose, it is preferred that the first bonding material 11 and the second bonding material 12 described above are paste solder or plate solder. However, there is a limit to the supply amount of paste solder and plate solder, so it is impossible to supply a sufficient amount that takes into account the influence of warping like molten solder. Therefore, it is difficult to handle the conventional paste solder and plate solder for a structure that generates warping. However, in the first embodiment, the bonding member 8B of the lead portion 8 is movable during bonding, so the semiconductor element 10 and the lead portion 8 are stably bonded even if the first bonding material 11 and the second bonding material 12 are solder paste or plate-like solder.

[0045] <Implementation method 2>

[0046] A semiconductor device in Embodiment 2 will be described. Note that descriptions of the same configurations and operations as those in Embodiment 1 will be omitted.

[0047] Figure 7 This is a cross-sectional view showing the state of the semiconductor device in the second embodiment at a high temperature.

[0048] The semiconductor device includes a base plate 2, an insulating circuit substrate 4, a lead portion 8, and a plurality of semiconductor elements 10. The structures of the base plate 2 and the insulating circuit substrate 4 are the same as those of the first embodiment.

[0049] The plurality of semiconductor elements 10 include a first semiconductor element 10A and two second semiconductor elements 10B. The first semiconductor element 10A is arranged closer to the center side of the insulating substrate 4A than the two second semiconductor elements 10B. The first semiconductor element 10A and the second semiconductor element 10B are formed of, for example, semiconductors such as Si or so-called wide-bandgap semiconductors such as SiC and GaN. The first semiconductor element 10A and the second semiconductor element 10B are, for example, IGBTs, MOSFETs, Schottky barrier diodes, etc. The first semiconductor element 10A and the second semiconductor element 10B are, for example, semiconductor elements for electric power (power semiconductor elements).

[0050] The lead portion 8 includes a lead body 8A and a bonding component 8B. The lead body 8A includes an opening 8C and a bonding component 8D. The opening 8C of the lead body 8A is provided corresponding to the mounting position of the first semiconductor element 10A. The bonding component 8D of the lead body 8A is provided corresponding to the mounting position of the second semiconductor element 10B. The back surface of the bonding component 8D is bonded to the second semiconductor element 10B by a third bonding material 13. The bonding component 8D has, for example, an embossed structure. The third bonding material 13 is, for example, solder. As in the first embodiment, the lower surface of the bonding component 8B provided on the first semiconductor element 10A in the opening 8C of the lead body 8A is bonded to the surface of the first semiconductor element 10A by the first bonding material 11. In addition, the outer periphery of the bonding component 8B is bonded to the inner periphery of the opening 8C of the lead body 8A by the second bonding material 12. The lead body 8A and the bonding component 8B are formed, for example, of Cu or Al. In addition, both ends of the lead portion 8 in the second embodiment are not held by the housing 5 .

[0051] The method for manufacturing a semiconductor device in the second embodiment is described. In the step of heating the semiconductor element 10 and the lead portion 8, due to the difference in linear expansion coefficients of the components, the semiconductor device 10 and the lead portion 8 are heated. Figure 7 As shown, the semiconductor element 10 is warped into a shape that is convex downward. Here, as in the first embodiment, a state in which the structure from the semiconductor element 10 to the base plate 2 is warped into a shape that is convex downward is described as an example. In this state, the displacement amount in the z direction of the second semiconductor element 10B located at the two end sides of the lead portion 8 is smaller than the displacement amount in the z direction of the first semiconductor element 10A. The two ends of the lead portion 8 in the second embodiment are not held by the housing 5, so not only the bonding member 8B but also the lead body 8A follows the displacement of the semiconductor element 10 caused by the warping. As a result, at the two end sides of the lead portion 8 where the bonding member 8B is not provided, the second semiconductor element 10B is stably bonded to the bonding portion 8D via the third bonding material 13. On the other hand, with respect to the first semiconductor element 10A having a large displacement amount in the z direction, the movable bonding member 8B moves in the z direction in a manner that follows the displacement, so that the first semiconductor element 10A is stably bonded to the bonding member 8B via the first bonding material 11. At this time, the second bonding material 12 on the upper surface of the bonding component 8B melts and flows between the outer periphery of the bonding component 8B and the inner periphery of the opening 8C of the lead body 8A. The outer periphery of the bonding component 8B is bonded to the inner periphery of the opening 8C of the lead body 8A through the second bonding material 12.

[0052] In summary, the semiconductor device in the second embodiment includes a first semiconductor element 10A mounted on a circuit pattern 4B provided on an insulating substrate 4A and a second semiconductor element 10B different from the first semiconductor element 10A. The lead body 8A includes a bonding portion 8D bonded to the second semiconductor element 10B on the back surface via a third bonding material 13. The semiconductor element 10A is arranged closer to the center than the second semiconductor element 10B in the surface of the insulating substrate 4A.

[0053] According to such a structure, similarly to the first embodiment, the bonding reliability between the lead portion 8 and the semiconductor element 10 is improved. In addition, even when a plurality of semiconductor elements 10 are bonded to the long lead portion 8, the number of bonding members 8B and openings 8C can be reduced. Therefore, the manufacturing cost and assemblability of the semiconductor device are improved.

[0054] <Implementation method 3>

[0055] A semiconductor device and a method for manufacturing the semiconductor device in Embodiment 3 are described. Embodiment 3 is a subordinate concept of Embodiment 1, and the semiconductor device in Embodiment 3 includes the structures of the semiconductor device in Embodiment 1. In addition, descriptions of structures and operations that are the same as those in Embodiment 1 or 2 are omitted.

[0056] Figure 8 It is a cross-sectional view showing the opening portion 8C of the lead body 8A and the bonding component 8B before bonding in Embodiment 3. The lead portion 8 includes the lead body 8A and the bonding component 8B in the same manner as in Embodiments 1 and 2. In Embodiment 3, the wettability of the bonding component 8B at the central portion of the upper surface with respect to the second bonding material 12 is lower than the wettability of the bonding component 8B at the peripheral portion thereof with respect to the second bonding material 12. For example, the bonding component 8B has a wettability control structure 15 at the central portion of its upper surface. In other words, the wettability of the wettability control structure 15 with respect to the second bonding material 12 is lower than the wettability of the surrounding portion thereof with respect to the second bonding material 12. The wettability control structure 15 is preferably a solder resist layer.

[0057] In the method for manufacturing a semiconductor device according to the third embodiment, the steps of preparing the semiconductor element 10 and placing the lead body 8A are as follows: Figure 3 The steps S1 and S2 shown are respectively the same.

[0058] In step S3, the bonding member 8B placed on the semiconductor element 10 includes the second bonding material 12 on the upper surface. The second bonding material 12 is Figure 8 As shown, it is provided on the wettability control structure 15. The second bonding material 12 is, for example, a solder paste or a solder plate.

[0059] In step S4, the semiconductor element 10 and the lead portion 8 are heated. When the second bonding material 12 on the upper surface of the bonding component 8B melts, the wettability control structure 15 prevents the second bonding material 12 from gathering at the center of the upper surface. Therefore, the melted second bonding material 12 easily flows between the outer periphery of the bonding component 8B and the inner periphery of the opening 8C of the lead body 8A. Fig. 9 1 is a cross-sectional view showing the opening 8C of the lead body 8A and the bonding member 8B after bonding in Embodiment 3. The outer periphery of the bonding member 8B is stably bonded to the inner periphery of the opening 8C of the lead body 8A by the second bonding material 12. Fig. 9 Although illustration thereof is omitted, similarly to the first embodiment, in step S4 , the lower surface of the bonding member 8B is bonded to the semiconductor element 10 via the first bonding material 11 .

[0060] In the semiconductor device and the method for manufacturing the same as described above, the ease of joining between the joining member 8B and the lead body 8A is improved.

[0061] <Implementation method 4>

[0062] A semiconductor device and a method for manufacturing the semiconductor device in Embodiment 4 are described. Embodiment 4 is a subordinate concept of Embodiment 1, and the semiconductor device in Embodiment 4 includes the structures of the semiconductor device in Embodiment 1. The same structures and operations as those in any of Embodiments 1 to 3 are not described.

[0063] Fig.10 1 is a cross-sectional view showing an opening portion 8C of a lead body 8A and a bonding component 8B before bonding in Embodiment 4. The lead portion 8 includes a lead body 8A and a bonding component 8B in the same manner as in Embodiments 1 and 2. The lead body 8A in Embodiment 4 has an inclined surface inclined upward on its inner periphery. In addition, the bonding component 8B does not include a second step portion 82, and its side surfaces are coplanar.

[0064] In the method for manufacturing a semiconductor device according to the fourth embodiment, the steps of preparing the semiconductor element 10, placing the lead body 8A, and placing the bonding member 8B are performed in parallel. Figure 3 The steps S1, S2 and S3 shown are respectively the same.

[0065] In step S4, if Fig.10As shown, before heating the semiconductor element 10 and the lead portion 8, the second bonding material 12 is inserted in a manner that contacts the side surface of the outer periphery of the bonding component 8B and the inclined surface of the opening portion 8C of the lead body 8A. Here, the second bonding material 12 is, for example, a linear solder. By heating the semiconductor element 10 and the lead portion 8, the second bonding material 12 is melted, and the outer periphery of the bonding component 8B is stably bonded to the inner periphery of the opening portion 8C of the lead body 8A through the second bonding material 12. Similar to the first embodiment, in this step S4, the lower surface of the bonding component 8B is bonded to the semiconductor element 10 through the first bonding material 11.

[0066] In the semiconductor device and the manufacturing method thereof, the bonding between the bonding member 8B and the lead body 8A is easier to bond. In the fourth embodiment, the side surface of the opening 8C of the lead body 8A is an example of an inclined surface, but the present invention is not limited to this and may be a vertical surface.

[0067] <Implementation method 5>

[0068] A semiconductor device and a method for manufacturing the semiconductor device in Embodiment 5 are described. Embodiment 5 is a subordinate concept of Embodiment 1, and the semiconductor device in Embodiment 5 includes the structures of the semiconductor device in Embodiment 1. In addition, descriptions of structures and operations that are the same as those in any of Embodiments 1 to 4 are omitted.

[0069] Fig.11 1 is a cross-sectional view showing an opening portion 8C of a lead body 8A and a bonding component 8B before bonding in Embodiment 5. The lead portion 8 includes a lead body 8A and a bonding component 8B as in Embodiment 1. In addition, as in Embodiment 1, the lead body 8A includes a first step portion 81 protruding from the inner periphery of the opening portion 8C to the inner side of the opening portion 8C, and the bonding component 8B includes a second step portion 82 protruding to the outer side of the outer periphery.

[0070] In the method for manufacturing a semiconductor device according to the fifth embodiment, the steps of preparing the semiconductor element 10 and placing the lead body 8A are as follows: Figure 3 The steps S1 and S2 shown are respectively the same.

[0071] In step S3, if Fig.11 As shown, the bonding member 8B placed on the semiconductor element 10 includes a second bonding material 12 pre-applied to the contact surface of the second step portion 82. The second bonding material 12 is, for example, a solder paste or a solder plate. No bonding material is provided on the contact surface of the first step portion 81 arranged opposite to the contact surface of the second step portion 82.

[0072] In step S4, the semiconductor element 10 and the lead portion 8 are heated. The melted second bonding material 12 easily bonds the contact surface of the second step portion 82 to the contact surface of the first step portion 81. That is, the outer periphery of the bonding component 8B is bonded to the inner periphery of the opening 8C of the lead body 8A through the second bonding material 12. Fig.11 Although illustration thereof is omitted, similarly to the first embodiment, in step S4 , the lower surface of the bonding member 8B is bonded to the semiconductor element 10 via the first bonding material 11 .

[0073] In the semiconductor device and the method for manufacturing the same as described above, the ease of joining between the joining member 8B and the lead body 8A is improved.

[0074] <Implementation method 6>

[0075] A semiconductor device and a method for manufacturing the semiconductor device in Embodiment 6 will be described. The semiconductor device in Embodiment 6 includes the structures of the semiconductor device in Embodiment 1. In addition, descriptions of structures and operations that are the same as those in any of Embodiments 1 to 5 will be omitted.

[0076] The lead portion 8 includes a lead body 8A and a bonding member 8B similarly to Embodiments 1 and 2. The thermal capacity of the bonding member 8B in Embodiment 6 is smaller than that of the lead body 8A. For example, the bonding member 8B and the lead body 8A are formed of different metals.

[0077] According to this structure, Figure 3 In step S4 shown, the temperature rise of the bonding member 8B is accelerated, and heat transfer to the first bonding material 11 and the second bonding material 12 is facilitated. Therefore, the bonding of the semiconductor element 10, the bonding member 8B, and the lead body 8A is facilitated.

[0078] <Implementation method 7>

[0079] A semiconductor device and a method for manufacturing the semiconductor device in Embodiment 7 will be described. Note that descriptions of the same configurations and operations as those in any of Embodiments 1 to 6 will be omitted.

[0080] Fig.12 This is a cross-sectional view showing the state of the semiconductor device at high temperature in the method for manufacturing the semiconductor device of Embodiment 7. The lead portion 8 includes a lead body 8A and a bonding member 8B as in Embodiments 1 and 2. The bonding member 8B in Embodiment 7 includes a micro convex portion 8E protruding from the contact surface with the second bonding material 12, that is, the lower surface. The micro convex portion 8E is formed by dowel processing.

[0081] According to such a structure, a certain thickness of the second bonding material 12 corresponding to the micro-convex portion 8E is ensured. Therefore, the assemblability of the semiconductor device is improved.

[0082] In addition, the present invention can freely combine the various embodiments within the scope of the present invention, or can appropriately modify or omit the various embodiments.

[0083] While the present invention has been described in detail, the above description is in all aspects illustrative and the present invention is not limited thereto, and it will be understood that numerous modifications not shown here are conceivable without departing from the scope of the present invention.

[0084] Description of the label

[0085] 2 base plate, 3 solder, 4 insulating circuit substrate, 4A insulating substrate, 4B circuit pattern, 4C circuit pattern, 5 housing, 8 lead portion, 8A lead body, 8B bonding component, 8C opening portion, 8D bonding portion, 8E micro-convex portion, 9 solder, 10 semiconductor element, 10A first semiconductor element, 10B second semiconductor element, 11 first bonding material, 12 second bonding material, 13 third bonding material, 15 wettability control structure, 81 first step portion, 82 second step portion.

Claims

1. A semiconductor device comprising: A semiconductor element mounted on a circuit pattern provided on an insulating substrate; a lead portion having a plate-like shape and bonded to the semiconductor element via a first bonding material; and another semiconductor element mounted on the circuit pattern of the insulating substrate, The lead portion includes: a lead body including an opening provided corresponding to a mounting position of the semiconductor element; and a bonding member provided on the semiconductor element in the opening, The lower surface of the bonding member is bonded to the semiconductor element via the first bonding material, and the outer periphery of the bonding member is bonded to the inner periphery of the opening via the second bonding material. The lead body further includes a bonding portion whose back surface is bonded to the other semiconductor element via a third bonding material. The semiconductor element is arranged closer to the center than the other semiconductor elements in the plane of the insulating substrate.

2. The semiconductor device according to claim 1, wherein A housing is further provided, the housing accommodating the insulating substrate on which the semiconductor element is mounted and holding both ends of the lead portion.

3. A semiconductor device comprising: A semiconductor element mounted on a circuit pattern provided on an insulating substrate; and a lead portion having a plate-like shape and bonded to the semiconductor element via a first bonding material, The lead portion includes: a lead body including an opening provided corresponding to a mounting position of the semiconductor element; and a bonding member provided on the semiconductor element in the opening, The lower surface of the bonding member is bonded to the semiconductor element via the first bonding material, and the outer periphery of the bonding member is bonded to the inner periphery of the opening via the second bonding material. The wettability of the central portion of the upper surface of the bonding member with respect to the second bonding material is lower than the wettability of the outer peripheral portion of the bonding member with respect to the second bonding material.

4. The semiconductor device according to claim 3, wherein: The bonding member includes a solder resist layer at the central portion of the upper surface.

5. The semiconductor device according to any one of claims 1 to 4, wherein: The opening of the lead body includes an upwardly inclined surface on the inner periphery.

6. The semiconductor device according to any one of claims 1 to 4, wherein: The lead body further includes a first step portion protruding from the inner periphery of the opening to the inner side of the opening, The joining member includes a second step portion protruding to the outside of the outer peripheral portion, The first step portion and the second step portion are joined together by the second joining material.

7. The semiconductor device according to any one of claims 1 to 4, wherein: The heat capacity of the joining member is smaller than the heat capacity of the lead body.

8. The semiconductor device according to any one of claims 1 to 4, wherein: The joining member includes a protrusion on the lower surface.

9. A method for manufacturing a semiconductor device, comprising the following steps: preparing a semiconductor element mounted on a circuit pattern provided on an insulating substrate; as well as bonding a lead portion having a plate shape to the semiconductor element via a first bonding material, The step of bonding the lead portion to the semiconductor element includes the following steps: placing a lead body including an opening portion so that the opening portion corresponds to a mounting position of the semiconductor element; placing a bonding member on the semiconductor element in the opening; as well as The semiconductor element and the lead portion are heated so that the lower surface of the bonding member is bonded to the semiconductor element via the first bonding material, and the outer periphery of the bonding member is bonded to the inner periphery of the opening via the second bonding material. The method for manufacturing the semiconductor device further comprises the following steps: Other semiconductor elements to be mounted on the circuit pattern; as well as The other semiconductor element is bonded to the back side of the bonding portion of the lead body to be bonded to the other semiconductor element via a third bonding material. The semiconductor element is arranged closer to the center than the other semiconductor elements in the plane of the insulating substrate.

10. A method for manufacturing a semiconductor device, comprising the following steps: preparing a semiconductor element mounted on a circuit pattern provided on an insulating substrate; as well as bonding a lead portion having a plate shape to the semiconductor element via a first bonding material, The step of bonding the lead portion to the semiconductor element includes the following steps: placing a lead body including an opening portion so that the opening portion corresponds to a mounting position of the semiconductor element; placing a bonding member on the semiconductor element in the opening; as well as The semiconductor element and the lead portion are heated so that the lower surface of the bonding member is bonded to the semiconductor element via the first bonding material, and the outer periphery of the bonding member is bonded to the inner periphery of the opening via the second bonding material. In the step of placing the bonding member on the semiconductor element, the bonding member includes the second bonding material on an upper surface thereof, The wettability of the upper surface of the bonding member at a central portion with respect to the second bonding material is lower than the wettability of the upper surface of the bonding member at a peripheral portion with respect to the second bonding material.

11. The method for manufacturing a semiconductor device according to claim 9 or 10, wherein: The step of joining the outer peripheral portion of the joining member to the inner periphery of the opening includes inserting the second joining material so as to contact the side surface of the outer peripheral portion and the side surface of the inner periphery of the opening.

12. The method for manufacturing a semiconductor device according to claim 9 or 10, wherein: The lead body includes a first step portion protruding from the inner periphery of the opening to the inner side of the opening, The joining member includes a second step portion protruding to the outside of the outer peripheral portion, In the step of placing the bonding member, the bonding member includes the second bonding material applied in advance to the second step portion, The step of joining the outer peripheral portion of the joining member and the inner periphery of the opening includes joining the first step portion and the second step portion via the second joining material.

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