JP2012099773A - Manufacturing method of semiconductor module and semiconductor module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a reliable semiconductor module which includes a structure in which a structure mounting a conductor chip on a heat sink is provided in a mold layer.SOLUTION: Semiconductor chips 31 and 32 are joined on a heat sink 11 by soldering or the like (chip mounting process). Then, one ends of internal leads (leads) 41, 42 are respectively connected to cathode electrodes 312, 322 on surfaces of semiconductor chip bodies 311, 321 to be fixed thereto. Further, the other ends of the internal leads 41, 42 are respectively fixed to the other end sides of external leads 12, 13 by soldering (internal lead fix process). Subsequently, a rectangular shape mold layer 60 covering the semiconductor chips 31 and 32 is formed (mold process). After that, connecting parts 15, 16 are cut at the side close to the heat sink 11, and connecting parts 17 to 21 are cut.

Description

  The present invention relates to a method for manufacturing a semiconductor module having a configuration in which a configuration in which a semiconductor chip is mounted on a heat sink is provided in a mold layer. The present invention also relates to this semiconductor module.

  As a power semiconductor element that operates with a large current, there is a rectifying diode. Such a diode is mounted on a substrate (heat radiating plate) having a high heat dissipation property, molded, and electrode terminals are taken out from the outside. For example, these diodes are used in DC-DC converters. In this case, since a plurality of diodes are often connected in parallel, a plurality of diode chips (silicon chips) share one terminal in common. In many cases, the semiconductor module has a built-in structure. The diode chip has a size of, for example, a few mm square, and an anode electrode and a cathode electrode are provided on both sides thereof. The configuration of the semiconductor module in such a case is described in, for example, Patent Document 1 and Patent Document 2.

  The technique described in Patent Document 1 employs a structure in which anode electrodes of two diodes are connected to a common substrate side. As a result, an inexpensive semiconductor module that does not employ a special insulating structure is realized.

  The technology described in Patent Document 2 employs a structure in which a plurality of diode chips are mounted on the same heat sink and bent leads are drawn upward. At this time, leads of the same polarity in the plurality of diodes are arranged side by side. Further, the diode chip is sealed in the mold layer, and a part of the lead protrudes from the mold layer. Thereby, a semiconductor module that is easy to manufacture and easy to connect can be obtained.

JP 2004-297864 A JP-A-6-13537

  Although manufacturing of the semiconductor modules described in Patent Document 1 and Patent Document 2 is easy, the mechanical strength of the lead taken out to the upper side is a problem. This lead is electrically connected to the outside, but if a force is applied to the lead at that time, a force is directly applied to the diode chip (semiconductor chip) connected to the lead, and these are in the mold layer. In some cases, the junction between the two was destroyed or the diode chip was damaged. Also, not only when electrical connection is made to the leads, but also when manufacturing each component (lead or semiconductor chip), an excessive force is applied to the joints or semiconductor chips between them. Sometimes. For this reason, the reliability of this semiconductor module became low.

  Therefore, it has been difficult to easily manufacture a highly reliable semiconductor module.

  The present invention has been made in view of such problems, and an object thereof is to provide an invention that solves the above problems.

In order to solve the above problems, the present invention has the following configurations.
In the semiconductor module manufacturing method of the present invention, a structure in which a semiconductor chip is mounted on a heat sink is provided in a mold layer, and one pole of the semiconductor chip is connected to the heat sink and protrudes from the mold layer. A method of manufacturing a semiconductor module comprising a configuration in which the other pole of the semiconductor chip is connected to the lead, wherein the lead has an external lead protruding at one end from the mold layer, and one end at the semiconductor chip. Is connected to the other end of the external lead, and the heat dissipation plate and the external lead are connected using a plurality of connecting portions. A lead frame having a configuration in which the heat radiating plate and the external lead are integrated with each other on the substantially same plane as the outer frame portion is not used, and the lead frame is used. In the first bending process of bending a part of the external lead adjacent to the heat sink in the normal direction of the lead frame, a part of the external lead is bent in the lead frame. A second bending step for bending the connecting portion connected to the heat sink so that the heat sink moves to the side, and the heat sink on the side where the external leads are present when viewed from the heat sink. On the main surface, a chip mounting step for mounting the semiconductor chip so that one pole of the semiconductor chip is connected to the heat sink, and one end of the internal lead is connected to the other pole of the semiconductor chip. An internal lead fixing step of fixing and fixing the other end of the internal lead by connecting to a part of the external lead adjacent to the heat sink; and on the heat sink, the semiconductor chip and the inner lead Characterized by comprising a molding step of forming the mold layer in a configuration covering the lead, the.
In the semiconductor module manufacturing method of the present invention, an opening is provided in a part of the external lead adjacent to the heat sink, and the other end of the internal lead penetrates the opening in the internal lead fixing step. And projecting from the external lead.
The method of manufacturing a semiconductor module according to the present invention includes a plurality of sets of the semiconductor chip and the leads connected to the semiconductor chip.
In the semiconductor module of the present invention, a structure in which a semiconductor chip is mounted on one main surface of a heat sink is provided in a mold layer, and one pole of the semiconductor chip is connected to the heat sink, from the mold layer A semiconductor module having a configuration in which the other pole of the semiconductor chip is connected to a protruding lead, wherein the lead is connected to an external lead having one end protruding from the mold layer and one end connected to the semiconductor chip. And an internal lead made of an elastic body whose other end is connected to the other end side of the external lead, and the external lead is the same as the side on which the semiconductor chip is mounted as viewed from the heat sink And a part of the other end side adjacent to the heat radiating plate is bent toward the heat radiating plate. Oite, characterized in that said semiconductor chip and the inner leads are sealed in the mold layer.
In the semiconductor module of the present invention, an opening is provided in a part on the other end side of the external lead, and the other end of the internal lead protrudes from the external lead through the opening in the mold layer. It is characterized by having a form.
The semiconductor module of the present invention includes a plurality of sets of the semiconductor chip and the leads corresponding to the semiconductor chip.
In the semiconductor module of the present invention, the semiconductor chip is a diode chip.

  Since this invention is comprised as mentioned above, a highly reliable semiconductor module can be manufactured easily.

It is a perspective view which shows the structure of the lead frame used in the manufacturing method of the semiconductor module which concerns on embodiment of this invention in the state before mounting a semiconductor chip. It is a top view which shows the structure of the lead frame used in the manufacturing method of the semiconductor module which concerns on embodiment of this invention in the state before mounting a semiconductor chip. They are the perspective view (a) and the side view (b) which looked at the lead frame used in the manufacturing method of the semiconductor module which concerns on embodiment of this invention from the different direction. It is a perspective view which shows the structure on the lead frame used in the manufacturing method of the semiconductor module which concerns on embodiment of this invention in the state after a semiconductor chip is mounted. In the manufacturing method of the semiconductor module which concerns on embodiment of this invention, it is the perspective view (a) which shows the condition of fixation of an internal lead, and sectional drawing (b). It is a perspective view which shows the form at the time of connecting an electrode terminal from the outside in an example of the semiconductor module which concerns on embodiment of this invention. In the manufacturing method of the semiconductor module which concerns on embodiment of this invention, it is a perspective view of the form at the time of using the lead frame of another structure.

  Hereinafter, a semiconductor module according to an embodiment of the present invention will be described. In this semiconductor module, a structure in which two diode chips (silicon chip: semiconductor chip) are mounted on the same heat sink is enclosed in a mold layer. The anode electrode (one pole) of each diode chip is connected to this heat dissipation plate, and the lead connected to each cathode electrode (the other pole) protrudes from this mold layer. Here, the lead has an external lead whose one end protrudes from the mold layer and has an opening on the other end side, one end connected to the cathode electrode of the diode chip, and the other end connected to the other end side of the external lead. And internal leads.

  When manufacturing this semiconductor module, a lead frame in which an external lead, which is one of the leads, and a heat sink are integrated is used. A perspective view of the lead frame 10 is shown in FIG. Here, the lead frame 10 is manufactured from a flat plate in the form of FIG. 1A, and after the first bending process, the lead frame 10 is formed in the form of FIG. 1B, and after the second bending process, FIG. ). Moreover, the top view corresponding to this is shown to Fig.2 (a)-(c), respectively. Actually, the lead frame 10 is used in the form of a large area integrated in a form in which a large number are arranged, and a large number of semiconductor modules are manufactured using this. The lead frame 10 shown in FIGS. 1 and 2 is a portion corresponding to one semiconductor module in the large lead frame.

  As shown in FIGS. 1A and 2A, in the lead frame 10, the radiator plate 11 and the external leads 12 and 13 connect the connecting portions 15 to 21 between the outer frame portion 14. It is fixed using. However, the heat sink 11 and the external leads 12 and 13 are in contact only via the connecting portions 15 to 21 and the outer frame portion 14 and are not in direct contact.

  The lead frame 10 is made of, for example, copper or a copper alloy as a material that has high thermal conductivity and high electrical conductivity, has sufficient mechanical strength, and can be bent. For this reason, the form of Fig.1 (a) and FIG.2 (a) is formed by processing the flat plate comprised with this material. However, since the heat radiating plate 11 is set to be thicker than the external leads 12 and 13, in this flat plate, the portion that becomes the heat radiating plate 11 is thick and the portion that becomes the external leads 12 and 13 is thinner. The connecting portions 15 to 21 are preferably thin like the external leads 12 and 13 in order to be mechanically bent or cut later. After the flat plate is set to such a plate thickness, for example, press processing or the like is performed, whereby the lead frame 10 in the form shown in FIGS. 1A and 2A is manufactured. In this state, the heat radiating plate 11, the external leads 12, 13 and the outer frame portion 14 are all in a planar shape, and these are arranged on substantially the same plane. In addition, an opening is formed in the center of the connecting portions 17 and 18 connected to one end side of the external leads 12 and 13 so that these can be easily cut later.

  As shown in FIGS. 1 (a) and 2 (a), the heat sink 11 and the external leads 12 and 13 are formed with circular openings and notches. These are used later when fixing the heat sink 11 and the external leads 12 and 13 with screws. In addition, rectangular openings (openings) 121 and 131 are provided on the external leads 12 and 13 on the heat radiating plate 11 side, respectively.

  Next, in the lead frame 10 shown in FIGS. 1A and 2A, a part of the other end side of the external leads 12 and 13 is shown in FIGS. 1B and 2B. Thus, it is bent toward the lower side (first bending process). In this step, a part (the other end side) where the rectangular openings 121 and 131 are formed in the external leads 12 and 13 are both bent toward the normal direction (lower side in the figure) of the lead frame 10. . This operation can be performed by ordinary mechanical bending.

  Next, as shown in FIGS. 1 (c) and 2 (c), the heat radiating plate 11 is parallel to the original position and is on the lower side (the side where the external leads 12, 13 are partially bent). The connecting portions 15 and 16 connected to the heat radiating plate 11 are bent so as to move (second bending process). Thereby, the heat sink 11 moves in parallel below the outer frame portion 14. At this time, the bent tips of the external leads 12 and 13 are not in contact with the heat sink 11. FIG. 3A is a perspective view of the state of FIG. 1C and FIG. 2C viewed from the upper side of the arrow in FIG. 1C, and FIG. Shown in

  Through the above steps, the lead frame 10 is finally in the form shown in FIG. 1C, FIG. 2C, and FIG. In this state, the external leads 12 and 13 and the heat sink 11 are located on different planes, and a part of the other end side of the external leads 12 and 13 where the rectangular openings 121 and 131 are formed is the heat sink 11. The shape is bent toward the side.

  A semiconductor chip is mounted on the lead frame 10 in this form. Further, the internal lead is connected to the semiconductor chip, and the internal lead is connected to the external lead, whereby the lead (external lead) and the semiconductor chip are electrically connected. The semiconductor chip used here is, for example, a diode chip in which a diode is formed. The shape is a rectangular body, and the anode electrode of the diode is provided on the back surface side (side joined to the heat sink 11), and the cathode electrode is provided on the front surface side.

  FIG. 4 is a perspective view corresponding to FIG. 1, showing the subsequent steps for mounting the semiconductor chip on the lead frame 10 of the above-described form.

  First, as shown in FIG. 4A, the semiconductor chips 31 and 32 are bonded onto the heat sink 11 using solder or the like (chip mounting process). The semiconductor chips 31 and 32 are mounted on the main surface of the heat sink 11 on the side where the outer frame portion 14 and the external leads 12 and 13 are present when viewed from the heat sink 11. The semiconductor chips 31 and 32 are configured such that cathode electrodes 312 and 322 are formed on the surfaces of rectangular semiconductor chip bodies 311 and 321. When the semiconductor chips 31 and 32 are bonded, the anode electrode on the back surface of the semiconductor chips 31 and 32 and the heat radiating plate 11 are also bonded electrically, so that the substrate 11 serves as an anode terminal common to the semiconductor chips 31 and 32.

  Next, as shown in FIG. 4B, one end of each of the internal leads (leads) 41 and 42 is connected and fixed to the cathode electrodes 312 and 322 on the surfaces of the semiconductor chip bodies 311 and 321, respectively. Also, the other end of each of the internal leads 41 and 42 is fixed to the other end side of the external leads 12 and 13 (adjacent to the heat sink 11 and part of the bent external leads 12 and 13) with solder (internal leads). Fixing process). Thereby, the internal leads 41 and 42 are fixed in this structure. At this time, the other ends of the internal leads 41 and 42 penetrate the rectangular opening 121 in the external lead 12 and the rectangular opening 131 in the external lead 13, respectively, and are joined to the external leads 12 and 13 by solder.

  The internal leads 41 and 42 each have a shape bent in a crank shape, and the material thereof can be a conductive and elastically deformable material, and a material different from that of the lead frame 10 can be used. it can.

  FIG. 5A is an enlarged perspective view showing a bonding state among the external lead 12, the internal lead 41, and the semiconductor chip 31, and FIG. 5B is a sectional view of these bonding portions. The anode electrode 313 formed on the back surface of the semiconductor chip body 311 and the heat sink 11 are joined by the solder layer 51, and the cathode electrode 312 formed on the surface of the semiconductor chip body 311 and one end of the internal lead 41 (FIG. 5B The solder layer 52 is joined to the lower left surface in FIG. By forming the solder layer 53 in the rectangular opening 121 with the other end of the internal lead 41 (the right end in FIG. 5B) penetrating the rectangular opening 121 in the external lead 12, the internal lead 41 and The external lead 12 is joined. In addition, in the perspective view (FIG. 5A), the description of the solder layers 51 to 53 is omitted.

  Next, as shown in FIG. 4C, a rectangular mold layer 60 covering the semiconductor chips 31 and 32 is formed (molding step). The mold layer 60 is made of, for example, a resin material. This step is the same as the molding step performed when manufacturing a normal semiconductor module. At this time, all of the connecting portions 15 to 21 are exposed to the outside of the mold layer 60.

  Then, if the outer frame part 14 is separated by cutting the connecting parts 15 and 16 on the side close to the heat sink 11 and cutting the connecting parts 17 to 21, as shown in FIG. The semiconductor module 100 is obtained. When the semiconductor module 100 is used, wiring is connected to the external leads 12 and 13 from the outside.

  When the above manufacturing method is executed, the structure shown in FIG. 4C (the structure on the heat dissipation plate 11) can be handled together with the outer frame portion 14. As described above, in practice, a large number of semiconductor modules are manufactured simultaneously using a large lead frame in which a large number of lead frames 10 are arranged. Even in this case, the entire structure in which the structure shown in FIG. 4C is arranged can be handled using the outer frame portion 14. This is the same in the state of FIGS. 4A and 4B. In the subsequent steps after the semiconductor chips 31 and 32 are mounted, the entire structure is obtained by directly contacting the outer frame portion 14. It is possible to handle. At this time, since the external leads 12 and 13 and the heat radiating plate 11 are connected to the outer frame portion 14 via the connecting portions 15 to 21, the force applied by handling the outer frame portion 14 is the external leads 12, 13 and This force is transmitted to the heat sink 11 via the connecting portions 15 to 21 and this force is not directly transmitted to the semiconductor chips 31 and 32 which are the most important components in the semiconductor module. Further, since this force is not transmitted to the joint portion between the semiconductor chips 31 and 32 and the internal leads 41 and 42, the breakage of the solder joint portion between them is also suppressed.

  In order to manufacture a highly reliable semiconductor module with a high yield, the positional relationship among the leads (external leads, internal leads), the semiconductor chip, and the heat sink must be maintained with high accuracy in the above manufacturing process. is necessary. On the other hand, after the lead frame 10 is configured as shown in FIG. 1C, the positional relationship between the heat sink 11 and the external leads 12 and 13 is maintained by the connecting portions 15 to 21 and the outer frame portion 14. Further, the positional relationship between the internal leads 41 and 42 and these is maintained by the rectangular openings 121 and 131 in the external leads 12 and 13. For this reason, in the manufacturing method described above, the positional relationship between these components is maintained with high accuracy. For this reason, it is possible to easily manufacture a semiconductor module having a high yield and high reliability.

  A configuration when wiring is connected to the semiconductor module 100 will be described below. In this case, FIG. 6 is a perspective view showing a form when wiring is connected. First, FIG. 6A is an external perspective view after the mold layer 60 is formed. In this state, the upper portions of the external leads 12 and 13 protrude upward and outward from the mold layer 60.

  Next, as shown in FIG. 6B, two nuts 61 and 62 are embedded in the upper surface of the mold layer 60. The nuts 61 and 62 correspond to circular openings provided in the external leads 12 and 13, respectively.

  Next, as shown in FIG. 6C, the external leads 12 and 13 are bent inward. At this time, if the openings in the external leads 12 and 13 and the nuts 61 and 62 are in the corresponding positions, the wires 63 and 64 are passed through the openings from above, so that the wiring is connected to the external leads. 12 and 13 can be fixed with screws.

  That is, after forming the mold layer 60, the nuts 61 and 62 are installed on the upper surface of the mold layer 60 in the form shown in FIG.

  When the external leads 12 and 13 are bent inward, a large force is applied to them from the outside. However, even in such a case, in the semiconductor module 10 having the above structure, the external leads 12 and 13 are not directly fixed to the semiconductor chips 31 and 32, and the stress generated at this time causes the internal leads 41 and 42 to be elastic. It is alleviated by deformation. Further, the form shown in FIG. 5B is formed in the mold layer 60. In this case, since the other end of the internal lead 41 protrudes through the external lead 12, a force is applied to the external lead 12 in the direction indicated by the white arrow in FIG. In this case, the bonding resistance between the mold layer 60 and the external leads 12 and the internal leads 41 is also increased.

  When connecting the internal leads 41 and 42 to the external leads 12 and 13, the other ends of the internal leads 41 and 42 are passed through the rectangular openings 121 and 131, respectively, and then solder (solder layer 53). It is fixed with. For this reason, the positional accuracy of joining of the internal leads 41 and 42 and the external leads 12 and 13 is also increased.

  Therefore, the reliability of the semiconductor module 100 can be increased. In addition, the semiconductor module 100 can be easily manufactured using the lead frame 10 described above.

  In addition, the structure of the lead frame having the form in which the heat radiating plate, the leads (external leads, internal leads), the outer frame portion, and the connecting portion are connected is arbitrary as long as the above manufacturing method can be applied. For example, FIG. 7 shows a form after the molding process (corresponding to FIG. 4C) when using the lead frame 410 configured such that two semiconductor modules are manufactured side by side on two heat sinks. It is a perspective view. In the lead frame 410, the heat radiating plates 411 and 412 and the external leads 413 to 416 are used for each semiconductor module, and the outer frame portion 417 is disposed outside these. The heat radiating plate 411 and the heat radiating plate 412 are connected by connecting portions 418 to 422 in the vicinity of the center in the figure, and this structure is connected to the outer frame portion 417 by the connecting portion 423 at this location. Further, the left end portion of the heat sink 411 is connected to the outer frame portion 417 by the connecting portion 427 via the connecting portions 424 to 426. Similarly, the right end portion of the heat sink 412 is connected to the outer frame portion 417 by the connecting portion 431 via the connecting portions 428 to 430. The connection method between the external leads 413 and 414 and the outer frame portion 417 and the connection method between the external leads 415 and 416 and the external lead 417 are the same as those of the lead frame 10 shown in FIG.

  In the lead frame 410 used in the configuration of FIG. 7, a common connecting portion 423 is used in the adjacent heat sinks 411 and 412. Thereby, since the 2nd bending process can be performed in common with the adjacent heat sinks 411 and 412, the manufacturing process is simplified, and the positional accuracy of the heat sinks 411 and 412 after the second bending process is increased. Can be improved.

  In the above example, the rectangular leads 121 and 131 are formed on the other end side of the external leads 12 and 13, and the rectangular leads 121 and 131 are penetrated by the internal leads 41 and 42 to form the internal leads 41 and 42. The external leads 12 and 13 are connected, but these connection methods are arbitrary. For example, an opening having a shape other than a rectangle may be used, and these may be directly connected and fixed with solder without using the opening.

  In the above example, two pairs of semiconductor chips and leads are used, but these may be three or more. Alternatively, it is obvious that a semiconductor module can be similarly manufactured even with only one set. Further, although the heat radiating plate is used as a common anode electrode of two semiconductor chips, the heat radiating plate can be divided into two, and each can be used as an anode electrode of each semiconductor chip.

  In the above example, the semiconductor chip is mounted on the heat sink having a flat surface shape. However, the surface of the heat sink can be mounted in the same manner, and the above manufacturing method can be applied. As long as it is optional. For example, irregularities that facilitate mounting of semiconductor chips can be formed as appropriate.

  In the above example, the anode electrode of the diode is connected to the heat radiating plate side and the cathode electrode is connected to the lead side. However, it is obvious that the same effect can be obtained even if these are reversed. It is obvious that a similar configuration can be used in a semiconductor module using a semiconductor device that is driven using not only a diode but also two electrode terminals.

10, 410 Lead frame 11, 411, 412 Heat sink 12, 13, 413-416 External lead (lead)
14, 417 Outer frame portion 15-21, 418-431 Connection portion 31, 32 Semiconductor chip 41, 42 Internal lead (lead)
51-53 Solder layer 60 Mold layer 100 Semiconductor module 121, 131 Rectangular opening (opening)
311 and 321 Semiconductor chip body (semiconductor chip)
312 and 322 Cathode electrode (semiconductor chip)
313 Anode electrode (semiconductor chip)

Claims (7)

A structure in which a semiconductor chip is mounted on a heat sink is provided in the mold layer, one pole of the semiconductor chip is connected to the heat sink, and the other pole of the semiconductor chip is connected to a lead protruding from the mold layer. A method for manufacturing a semiconductor module having a configuration in which
An external lead whose one end protrudes from the mold layer, and an internal lead composed of an elastic body having one end connected to the semiconductor chip and the other end connected to the other end of the external lead; And comprising
The heat sink and the external lead have a configuration in which the heat sink and the external lead are integrated with each other on a substantially same plane with the outer frame portion using a plurality of connecting portions. A lead frame is used,
In the lead frame, a first bending step of bending a part of the external lead adjacent to the heat sink in a normal direction of the lead frame;
In the lead frame, a second bending step of bending the connecting portion connected to the heat sink so that the heat sink moves to a side where a part of the external lead is bent;
A chip mounting step of mounting the semiconductor chip so that one pole of the semiconductor chip is connected to the heat sink on the main surface of the heat sink on the side where the external leads are present when viewed from the heat sink; ,
An internal lead fixing step of connecting and fixing one end of the internal lead to the other pole of the semiconductor chip and connecting the other end of the internal lead to a part of the external lead adjacent to the heat sink When,
On the heat sink, a molding step of forming the mold layer in a configuration covering the semiconductor chip and the internal leads;
A method for manufacturing a semiconductor module, comprising: An opening is provided in a part of the external lead adjacent to the heat sink,
In the internal lead fixing step,
2. The method of manufacturing a semiconductor module according to claim 1, wherein the other end of the internal lead penetrates the opening and protrudes from the external lead.   3. The method of manufacturing a semiconductor module according to claim 1, further comprising a plurality of sets of the semiconductor chip and the leads connected to the semiconductor chip. A structure in which a semiconductor chip is mounted on one main surface of a heat radiating plate is provided in the mold layer, one pole of the semiconductor chip is connected to the heat radiating plate, and the semiconductor chip is connected to a lead protruding from the mold layer A semiconductor module having a configuration in which the other pole is connected,
The lead is an external lead having one end protruding from the mold layer, an internal lead composed of an elastic body having one end connected to the semiconductor chip and the other end connected to the other end of the external lead, Consists of
The external lead is installed on the same side as the side on which the semiconductor chip is mounted as viewed from the heat sink so as not to directly contact the heat sink, and a part of the other end adjacent to the heat sink Is a shape bent toward the heat sink side,
A semiconductor module, wherein the semiconductor chip and the internal lead are sealed in the mold layer on the heat sink. An opening is provided in a part on the other end side of the external lead,
5. The semiconductor module according to claim 4, wherein the other end of the internal lead penetrates the opening and protrudes from the external lead in the mold layer.   6. The semiconductor module according to claim 4, comprising a plurality of sets of the semiconductor chip and the leads corresponding to the semiconductor chip.   The semiconductor module according to any one of claims 4 to 6, wherein the semiconductor chip is a diode chip.