SEMICONDUCTOR MODULE, SEMICONDUCTOR DEVICE, AND SEMICONDUCTOR DEVICE MANUFACTURING METHOD

A semiconductor module includes an insulating sheet, a first terminal, and a second terminal that extend from inside a resin case to the outside. The first terminal is disposed on the first surface of the insulating sheet so as to overlap the insulating sheet in plan view, and includes a first tip portion that is spaced apart from the first surface in a thickness direction. The second terminal is disposed on the second surface of the insulating sheet so as to overlap the insulating sheet and first terminal in plan view, and includes a second tip portion that is spaced apart from the second surface in the thickness direction. The insulating sheet extends from inside the resin case further to the outside than do the first tip portion and the second tip portion.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The embodiments discussed herein relate to a semiconductor module, a semiconductor device, and a semiconductor device manufacturing method.

2. Background of the Related Art

For example, a semiconductor module having a power conversion function includes therein a power device. As such a power device, an insulated gate bipolar transistor (IGBT), a metal-oxide-semiconductor field-effect transistor (MOSFET), or another is used. A capacitor may be connected to the semiconductor module in order to stabilize a direct current voltage to be applied.

For such a semiconductor module that is connected to a capacitor, there is known a technique of providing the following terminal portions in the semiconductor module. More specifically, there is known a technique in which, as each terminal portion of the semiconductor module, a multilayer terminal portion is formed by sequentially stacking a first power terminal, an insulating sheet, and a second power terminal in such a manner that a part of the first power terminal is exposed from the insulating sheet and that the second power terminal is located on the insulating sheet with a terrace portion of the insulating sheet between the part of the first power terminal and the second power terminal (Japanese Laid-open Patent Publication No. 2021-106235). A first connection terminal and second connection terminal of the capacitor are respectively bonded by laser welding to the first power terminal exposed from the insulating sheet and the second power terminal provided on the insulating sheet in this multilayer terminal portion.

Further, for a semiconductor module that has a first main terminal and second main terminal that are respectively continuous from a first conductive member and second conductive member arranged with a semiconductor element sandwiched therebetween and extend to the outside of a sealing resin body, there is known a technique in which a first bus bar and second bus bar, which are arranged with an insulation member therebetween, are connected respectively to exposed portions of the first main terminal and second main terminal that are formed on the same side or different sides of the first main terminal and second main terminal depending on the locations of the first main terminal and second main terminal with respect to the sealing resin body (Japanese Laid-open Patent Publication No. 2020-150019).

Still further, there is known a technique in which an insulating member disposed between a first input terminal and second input terminal of a semiconductor device is inserted in the gap between a pair of separate portions formed in an insulator disposed between a first supply terminal and second supply terminal of a bus bar, the first supply terminal and second supply terminal are respectively placed on the external portions of the first input terminal and second input terminal, and the first supply terminal and second supply terminal are conductively bonded respectively to the first input terminal and second input terminal by laser welding (International Publication Pamphlet No. 2019/239771 and International Publication Pamphlet No. 2020/045263).

Still further, there is known a technique in which a positive power terminal and negative power terminal of a semiconductor module, which respectively have power terminal protruding portions that are disposed so as not to overlap each other when viewed in one direction, are connected to a positive bus bar terminal and negative bus bar terminal of a capacitor, which respectively have a positive terminal protruding portion and negative terminal protruding portion that are disposed so as not to overlap each other when viewed in the one direction (Japanese Laid-open Patent Publication No. 2018-67990). In this technique, the positive terminal protruding portion and negative terminal protruding portion do not overlap an insulating member disposed between the positive bus bar terminal and the negative bus bar terminal in the capacitor, the positive power terminal and negative power terminal of the semiconductor module are respectively disposed on the outer sides of the positive terminal protruding portion and negative terminal protruding portion, the positive terminal protruding portion and positive power terminal are welded to each other at the upper ends or facing surfaces thereof, and the negative terminal protruding portion and negative power terminal are welded to each other at the upper ends or facing surfaces thereof.

Still further, there is known a technique in which a semiconductor element bonded to one conductive substrate and another conductive substrate are conductively connected to each other with a lead member. For this technique, there are known a technique in which the lead member bonded to the semiconductor element via a lead bonding layer is bonded to the other conductive substrate by laser welding and a technique in which a metal plate disposed on the semiconductor element is bonded to the lead member by laser welding (International Publication Pamphlet No. 2020/071185 and International Publication Pamphlet No. 2020/179369).

By the way, consider the case where the terminal portion of a semiconductor module to which a capacitor is connected has a multilayer structure in which a positive terminal and a negative terminal sandwich an insulating sheet therebetween. If a connecting member is placed on a terminal disposed directly on the insulating sheet and heat is applied by laser irradiation or the like from the connecting member side for the welding, the heat generated during the welding may damage the insulating sheet disposed directly under the terminal. The damage in the insulating sheet may deteriorate the original insulation performance and thus decrease the withstand voltage.

SUMMARY OF THE INVENTION

According to an aspect, there is provided a semiconductor module, including: a resin case; an insulating sheet having a first surface and a second surface opposite to the first surface, the insulating sheet extending from inside the resin case to outside; a first terminal extending from inside the resin case to the outside, the first terminal being disposed on the first surface of the insulating sheet, except for a tip portion thereof that is spaced apart from the first surface in a thickness direction perpendicular to the first surface, the first terminal overlapping the insulating sheet in a plan view of the semiconductor module, the tip portion of the first terminal being a first tip portion; and a second terminal extending from inside the resin case to the outside, the second terminal being disposed on the second surface of the insulating sheet, except for a tip portion thereof that is spaced apart from the second surface in the thickness direction, the second terminal overlapping the insulating sheet and the first terminal in the plan view, the tip portion of the second terminal being a second tip portion, wherein the insulating sheet extends further outside than the first tip portion and the second tip portion.

DETAILED DESCRIPTION OF THE INVENTION

First, an example of a semiconductor device including a semiconductor module and a capacitor will be described.

FIG.1is a view for describing an example of a semiconductor device.FIG.1is a schematic perspective view illustrating a main part of the example semiconductor device.

The semiconductor device100illustrated inFIG.1includes a semiconductor module110, a capacitor120, and connecting members130connecting the semiconductor module110and the capacitor120to each other.

The semiconductor module110includes a resin case111. The resin case111has a frame-shaped portion (frame portion). The resin case111may further has a cover to cover an inner space surrounded by the frame portion. The resin case111may be made of a polyphenylene sulfide resin or another. Inside the resin case111, or in the inner space surrounded by its frame portion, an insulated circuit substrate, and semiconductor elements and others mounted on the insulated circuit substrate are accommodated.

For example, as the insulated circuit substrate, a substrate formed by forming a conductive layer having a predetermined pattern on both principal surfaces of a ceramic substrate is used. As the ceramic substrate, a substrate made of alumina, composite ceramics containing alumina as a main component, aluminum nitride, silicon nitride, or another material is used. For the conductive layer, a metal such as copper or aluminum is used. As the insulated circuit substrate, a direct copper bonding (DCB) substrate, an active metal brazed (AMB) substrate, or another may be used.

Examples of a semiconductor element mounted on the insulated circuit substrate include an IGBT, a MOSFET, and others. Other examples of the semiconductor element include a diode such as a free-wheeling diode (FWD) and a Schottky barrier diode (SBD). Such a diode may be integrated with an IGBT or MOSFET. Furthermore, components to be connected to the semiconductor element may be mounted on the insulated circuit substrate.

At one side of the resin case111of the semiconductor module110, which accommodates the insulated circuit substrate, and the semiconductor elements and others mounted on the insulated circuit substrate, terminal structure portions112are provided, which are connected to the accommodated insulated circuit substrate, semiconductor elements, and others and are used to connect the semiconductor module110to the capacitor120provided external to the semiconductor module110. Here, the semiconductor module110illustrated as an example has three terminal structure portions112provided at the one side of the resin case111.

The capacitor120includes a resin case121. The resin case121is made of a polyphenylene sulfide resin or another. A capacitor element is accommodated in the resin case121. At one side of the resin case121, terminal structure portions122are provided, which are connected to the accommodated capacitor element and are used to connect the capacitor120to the semiconductor module110provided external to the capacitor120. Here, the capacitor120illustrated as an example has three terminal structure portions122provided at the one side of the resin case121.

The semiconductor module110and the capacitor120are disposed such that their terminal structure portions112and terminal structure portions122face each other, and each terminal structure portion112and its corresponding terminal structure portion122are connected to each other with a connecting member130such as a bus bar. For example, the semiconductor device100is implemented by connecting the semiconductor module110and the capacitor120to each other in this manner. In the semiconductor device100, circuits having predetermined functions, such as a power conversion circuit and an inverter circuit, are formed with the insulated circuit substrate and the semiconductor elements and others mounted on the insulated circuit substrate provided in the semiconductor module110and the capacitor element provided in the capacitor120.

The connecting part between the semiconductor module110and the capacitor120in the semiconductor device100configured as described above will now be described.

FIG.2is a view for describing an example of the connecting part between a semiconductor module and a capacitor.FIG.2is a schematic sectional view taken along a line II-II ofFIG.1.

For example, as illustrated inFIG.2, a terminal structure portion112that includes a multilayer structure116formed of a first terminal113, an insulating sheet114, and a second terminal115is provided on the resin case111of the semiconductor module110. For example, the first terminal113serves as the negative electrode (N) terminal of the semiconductor module110, and the second terminal115serves as the positive electrode (P) terminal of the semiconductor module110. The first terminal113and second terminal115are connected to the insulated circuit substrate accommodated in the resin case111or respectively to the negative electrode and positive electrode of a semiconductor element or a component connected thereto accommodated in the resin case111. The first terminal113, insulating sheet114, and second terminal115are stacked in such a manner that the insulating sheet114is interposed between the first terminal113and the second terminal115. The first terminal113and second terminal115are made of a metal such as copper or aluminum. The insulating sheet114is made of a resin material such as an aramid resin, a polyamide resin, a fluororesin, or a polyimide resin.

The multilayer structure116formed of the first terminal113, insulating sheet114, and second terminal115penetrates through a part of the resin case111and is placed on a terrace portion117formed in the resin case111. The multilayer structure116is placed on the terrace portion117in such a manner that the first terminal113, insulating sheet114, and second terminal115are stacked in a stepped form. For example, a tip portion115aof the second terminal115located closest to the terrace portion117extends to the outside of the resin case111.

For example, as illustrated inFIG.2, a terminal structure portion122that includes a third terminal123, an insulating sheet124, and a fourth terminal125is provided on the resin case121of the capacitor120that is connected to the semiconductor module110. For example, the third terminal123serves as the N terminal of the capacitor120, and the fourth terminal125serves as the P terminal of the capacitor120. The third terminal123and fourth terminal125are made of a metal such as copper or aluminum. The insulating sheet124is made of a resin material such as an aramid resin, a polyamide resin, a fluororesin, or a polyimide resin.

For example, as illustrated inFIG.2, the third terminal123has one end connected to the resin case121and is bent so that the other end thereof extends toward the inner side of the resin case121. The fourth terminal125is disposed outside the third terminal123on the resin case121, and has one end connected to the resin case121and is bent so that the other end thereof extends to the outer side of the resin case121. The insulating sheet124has one end connected to the resin case121at a position between the third terminal123and the fourth terminal125, and has flexibility so as to be bent toward the fourth terminal125. The insulating sheet124has such a size that it is able to cover the fourth terminal125when bent toward the fourth terminal125.

The semiconductor module110and the capacitor120are arranged such that the terminal structure portion112of the resin case111and the terminal structure portion122of the resin case121face each other. Then, the tip portion115aof the second terminal115of the semiconductor module110exposed from the insulating sheet114is connected to the fourth terminal125of the capacitor120.

The second terminal115of the semiconductor module110and the fourth terminal125of the capacitor120are connected by, for example, laser welding. Alternatively, another technique such as ultrasonic welding or friction stir welding may be employed to connect the second terminal115of the semiconductor module110to the fourth terminal125of the capacitor120. The fourth terminal125of the capacitor120is placed on the second terminal115of the semiconductor module110, and heat is applied by laser irradiation or another from the side where the fourth terminal125is located, so that the fourth terminal125and the second terminal115are melt and solidified at a welding area102aand are thereby welded to each other.

After the second terminal115of the semiconductor module110and the fourth terminal125of the capacitor120are connected to each other, the insulating sheet124of the capacitor120is bent toward the connecting part between the second terminal115and the fourth terminal125. By bending the insulating sheet124of the capacitor120in this manner, the fourth terminal125, the tip portion115aof the second terminal115connected thereto, and a part of the insulating sheet114are covered with the bent insulating sheet124.

After the insulating sheet124of the capacitor120is bent, the first terminal113of the semiconductor module110and the third terminal123of the capacitor120are connected to each other with a connecting member130such as a bus bar. The connecting member130is made of a metal such as copper or aluminum. The connecting member130is placed such as to lie over the insulating sheet124of the capacitor120, which is provided to cover the connecting part between the second terminal115of the semiconductor module110and the fourth terminal125of the capacitor120and the insulating sheet114of the semiconductor module110, so that the connecting member130is connected to the first terminal113of the semiconductor module110and to the third terminal123of the capacitor120.

The connecting member130is connected to the first terminal113of the semiconductor module110and to the third terminal123of the capacitor120by, for example, laser welding. Alternatively, another technique such as ultrasonic welding or friction stir welding may be employed to connect the connecting member130to the first terminal113of the semiconductor module110and to the third terminal123of the capacitor120. The connecting member130is placed on the first terminal113of the semiconductor module110and the third terminal123of the capacitor120, and heat is applied by laser irradiation or another from the side where the connecting member130is located. Thereby, the connecting member130, third terminal123, and first terminal113are melt and solidified at a welding area102band a welding area102c, so that the connecting member130is welded to the third terminal123and to the first terminal113.

For example, by connecting the terminal structure portion112and the terminal structure portion122to each other with the connecting member130as described above, the semiconductor module110and the capacitor120are connected to each other.

The following describes the welding of the first terminal113of the semiconductor module110and the connecting member130.

FIGS.3A to3Care views for describing how to weld a connecting member to a first terminal of a semiconductor module.FIGS.3A to3Care schematic sectional views illustrating an example of a welding step.

FIGS.3A to3Cmerely illustrate the insulating sheet114and first terminal113in the terminal structure portion112of the semiconductor module110and the connecting member130, for convenience. For example, in welding the connecting member130to the first terminal113, the connecting member130is first placed on the first terminal113, as illustrated inFIG.3A. Then, as illustrated inFIG.3B, heat140is applied by laser irradiation or another from the side where the connecting member130is located, so that the connecting member130and the first terminal113placed under the connecting member130are melt and solidified at a welding area102cand are thereby welded to each other.

Note, however, that the heat140by the laser irradiation or another may cause overheating during the welding, which may lead to excessive melting of the connecting member130and first terminal113. If this happens, the insulating sheet114undergoes thermal stress, and therefore a damage141may occur in the insulating sheet114, as illustrated inFIG.3C. As another possibility, the excessive melting of the first terminal113may cause the welding area102cto penetrate through the first terminal113to reach the insulating sheet114, and therefore a damage141may occur in the insulating sheet114. If such a damage141occurs in the insulating sheet114, the properties of the material at the area with the damage141and its surrounding area may change, which may prevent the insulating sheet114from maintaining its original insulation performance and accordingly may decrease the withstand voltage.

In view of the foregoing, the configurations that will be described in the following embodiments are employed to reduce the risk of damaging an insulating sheet during the welding of a terminal of a semiconductor module.

First Embodiment

FIGS.4A and4Bare views for describing an example of a semiconductor module according to a first embodiment.FIG.4Ais a schematic perspective view illustrating a main part of the example semiconductor module.FIG.4Bis a schematic sectional view illustrating the main part of the example semiconductor module.FIG.4Bis a sectional view taken along a line IV-IV ofFIG.4A, as seen in the arrow direction of the line IV-IV.

The semiconductor module10A illustrated inFIGS.4A and4Bincludes a resin case11and a terminal structure portion12A disposed at one side of the resin case11.

The resin case11of the semiconductor module10A has a frame portion. The resin case11may further have a cover to cover an inner space surrounded by the frame portion.FIGS.4A and4Billustrate a part of the one side of the frame portion of the resin case11. Note that the resin case11has an inner edge11aand an outer edge11bof the frame portion, and the inner edge11afaces the inner space surrounded by the frame portion.

The resin case11is made of a polyphenylene sulfide resin, for example. Alternatively, the resin case11may be made of a polybutylene terephthalate resin, a polybutylene succinate resin, a polyamide resin, an acrylonitrile-butadiene-styrene resin, or another. For example, the resin case11is formed by injection molding using such a resin material.

Inside the resin case11, or in the inner space surrounded by the frame portion of the resin case11, an insulated circuit substrate, and semiconductor elements and others mounted on the insulated circuit substrate are accommodated. For example, as the insulated circuit substrate, a substrate formed by forming a conductive layer having a predetermined pattern on both principal surfaces of a ceramic substrate is used. As the insulated circuit substrate, a DCB substrate, an AMB substrate, or another may be used. Examples of a semiconductor element mounted on the insulated circuit substrate include an IGBT and a MOSFET. In addition, components that are connected to the semiconductor elements may be mounted on the insulated circuit substrate.

The terminal structure portion12A is provided at one side of the frame portion of the resin case11that accommodates the above insulated circuit substrate, semiconductor elements, and others in the inner space thereof. A plurality of terminal structure portions12A may be provided at the one side of the resin case11of the semiconductor module10A.

The terminal structure portion12A includes a multilayer structure16formed of a first terminal13, an insulating sheet14, and a second terminal15. For example, the first terminal13serves as the N terminal of the semiconductor module10A, and the second terminal15serves as the P terminal of the semiconductor module10A. The first terminal13and second terminal15are connected to the insulated circuit substrate accommodated in the resin case11or respectively to the negative electrode and positive electrode of a semiconductor element or the like accommodated in the resin case11. The first terminal13, insulating sheet14, and second terminal15are stacked in such a manner that the insulating sheet14is interposed between the first terminal13and the second terminal15. The multilayer structure16formed of the first terminal13, insulating sheet14, and second terminal15penetrates through a part of the resin case11and is placed on a terrace portion17formed in the resin case11. For example, the multilayer structure16is pressed against the terrace portion17by a pressing portion11cwith a width W0of the resin case11. For example, in molding the resin case11using a resin material such as a polyphenylene sulfide resin, the terminal structure portion12A is formed by insert-molding the multilayer structure16using the resin material.

The insulating sheet14of the terminal structure portion12A is arranged to extend to the outside of the resin case11(beyond the outer edge11b). The insulating sheet14is provided such as to extend from inside the resin case11further to the outside than the first terminal13(a first tip portion13athereof) and the second terminal15(a second tip portion15athereof). The insulating sheet14is made of a resin material such as an aramid resin, a polyamide resin, a fluororesin, or a polyimide resin.

The first terminal13of the terminal structure portion12A is arranged to extend to the outside of the resin case11(beyond the outer edge11b). The first terminal13is disposed on the side of the insulating sheet14where the first surface14ais located such as to overlap the insulating sheet14in plan view. The first terminal13has the first tip portion13athat is spaced apart from the first surface14aof the insulating sheet14. The first terminal13has a first extending portion13bthat extends from the first tip portion13atoward the resin case11and that contacts the first surface14aof the insulating sheet14. For example, the first terminal13is bent between the first extending portion13band the first tip portion13aso that, when the first terminal13is arranged such that the first extending portion13bcontacts the first surface14aof the insulating sheet14, the first tip portion13ais spaced apart from the first surface14aof the insulating sheet14. The first terminal13is made of a metal such as copper or aluminum.

The second terminal15of the terminal structure portion12A is arranged to extend to the outside of the resin case11(beyond the outer edge11b). The second terminal15is disposed on the side of the insulating sheet14where the second surface14bopposite to the first surface14ais located such as to overlap the insulating sheet14and the first terminal13in plan view. The second terminal15has the second tip portion15athat is spaced apart from the second surface14bof the insulating sheet14. The second terminal15has a second extending portion15bthat extends from the second tip portion15atoward the resin case11and that contacts the second surface14bof the insulating sheet14. For example, in the second terminal15, the second tip portion15ais more recessed than the second extending portion15bso that, when the second terminal15is arranged such that the second extending portion15bcontacts the second surface14bof the insulating sheet14, the second tip portion15ais spaced apart from the second surface14bof the insulating sheet14. The second terminal15is made of a metal such as copper or aluminum.

A part (referred to as a “first portion”) of the first extending portion13bof the first terminal13that is a portion extending from the first tip portion13atoward the resin case11, a part (referred to as a “second portion”) of the second extending portion15bof the second terminal15that is a portion extending from the second tip portion15atoward the resin case11, and a part (referred to as a “third portion”) of the insulating sheet14sandwiched between the first portion and the second portion are placed on the terrace portion17formed in the resin case11. The first portion, second portion, and third portion are pressed against the terrace portion17by the pressing portion11cof the resin case11.

The semiconductor module10A configured as described above is connected to a capacitor. As a result, a semiconductor device including the semiconductor module10A and capacitor is implemented.

FIG.5is a view for describing an example of a semiconductor device according to the first embodiment.FIG.5is a schematic sectional view illustrating a main part of the example semiconductor device.

The semiconductor device1A illustrated inFIG.5includes the semiconductor module10A and a capacitor20A.

The capacitor20A includes a resin case21. The resin case21is made of a polyphenylene sulfide resin or another. A capacitor element is accommodated in the resin case21. At one side of the resin case21, a terminal structure portion22A is provided, which is connected to the accommodated capacitor element to connect the capacitor20A to the semiconductor module10A provided external to the capacitor20A. The terminal structure portion22A of the capacitor20A is arranged at a position corresponding to the terminal structure portion12A of the semiconductor module10A. A plurality of terminal structure portions22A may be provided at the one side of the resin case21.

The terminal structure portion22A of the capacitor20A includes a third terminal23, an insulating sheet24, and a fourth terminal25. For example, the third terminal23serves as the N terminal of the capacitor20A, and the fourth terminal25serves as the P terminal of the capacitor20A. The third terminal23and fourth terminal25are connected respectively to the negative electrode and positive electrode of the capacitor element accommodated in the resin case21. The third terminal23and fourth terminal25are made of a metal such as copper or aluminum. The insulating sheet24is made of a resin material such as an aramid resin, a polyamide resin, a fluororesin, or a polyimide resin.

In the terminal structure portion22A, the third terminal23has one end connected to the resin case21and is bent so that the other end thereof extends toward the outside of the resin case21(beyond an outer edge21athereof). The fourth terminal25has one end connected to the resin case21and is bent so that the other end thereof extends toward the outside of the resin case21. The one end of the fourth terminal25is located outside the one end of the third terminal23on the resin case21. The insulating sheet24has one end connected to the resin case21at a position between the one end of the third terminal23and the one end of the fourth terminal25, and has flexibility so as to be bent toward the fourth terminal25.

The third terminal23of the terminal structure portion22A has a third tip portion23a. The third tip portion23aof the third terminal23has a third tip surface23aathat faces a first tip surface13aaof the first tip portion13aof the first terminal13of the semiconductor module10A. For example, the third tip surface23aaof the third tip portion23aand the first tip surface13aaof the first tip portion13ahave the same shape. For example, the third tip portion23ais more recessed than a third extending portion23bextending from the third tip portion23atoward the resin case21.

The fourth terminal25of the terminal structure portion22A has a fourth tip portion25a. The fourth tip portion25aof the fourth terminal25has a fourth tip surface25aathat faces a second tip surface15aaof the second tip portion15aof the second terminal15of the semiconductor module10A. For example, the fourth tip surface25aaof the fourth tip portion25aand the second tip surface15aaof the second tip portion15ahave the same shape. For example, the fourth tip portion25ais more recessed than a fourth extending portion25bextending from the fourth tip portion25atoward the resin case21.

In connecting the semiconductor module10A and the capacitor20A to each other, the semiconductor module10A and the capacitor20A are arranged such that their terminal structure portion12A and terminal structure portion22A face each other. At this time, the first tip portion13aof the first terminal13of the semiconductor module10A and the third tip portion23aof the third terminal23of the capacitor20A are arranged such that their first tip surface13aaand third tip surface23aacontact each other. At the same time, the second tip portion15aof the second terminal15of the semiconductor module10A and the fourth tip portion25aof the fourth terminal25of the capacitor20A are arranged such that their second tip surface15aaand fourth tip surface25aacontact each other.

At this time, in the semiconductor module10A, the first tip portion13aof the first terminal13is located on the side of the insulating sheet14where the first surface14ais located, spaced apart from the insulating sheet14, and the second tip portion15aof the second terminal15is located on the side of the insulating sheet14where the second surface14bis located, spaced apart from the insulating sheet14. Similarly, in the capacitor20A, the third tip portion23aof the third terminal23, which is to contact the first tip portion13a, is located on the side of the insulating sheet14where the first surface14ais located, spaced apart from the insulating sheet14, and the fourth tip portion25aof the fourth terminal25, which is to contact the second tip portion15a, is located on the side of the insulating sheet14where the second surface14bis located, spaced apart from the insulating sheet14. On the side of the insulating sheet14where the first surface14ais located, the first tip portion13aand third tip portion23aare brought into contact with each other in a state of being spaced apart from the first surface14a. On the side of the insulating sheet14where the second surface14bis located, the second tip portion15aand fourth tip portion25aare brought into contact with each other in a state of being spaced apart from the second surface14b.

Then, heat is applied by, for example, laser irradiation to the contact area where the first tip portion13aand third tip portion23acontact each other, from the opposite side (upper side inFIG.5) of the contact area from the insulating sheet14. By doing so, the first tip portion13aand third tip portion23aare melt and solidified at a first welding area2aand are thereby welded to each other and a welding portion (2a) is formed. For example, with this technique, the first terminal13of the semiconductor module10A and the third terminal23of the capacitor20A are welded to each other. In this example, the heat is applied by laser irradiation to weld (laser-weld) the first terminal13and the third terminal23to each other. Alternatively, another technique such as ultrasonic welding or friction stir welding may be employed to apply heat from the opposite side from the insulating sheet14in order to weld the first terminal13and the third terminal23to each other.

In this connection, in the case of the laser welding, a metal plate made of copper, aluminum, or another may be inserted in the space formed between the contact area where the first tip portion13aand third tip portion23acontact each other and the insulating sheet14. Even if there is a gap in the contact area between the first tip portion13aand the third tip portion23a, the metal plate is able to prevent the laser from reaching the insulating sheet14through the gap, thereby reducing the risk of damaging the insulating sheet14due to the laser. In the case of the ultrasonic welding, friction stir welding, or another, the welding may be performed while a predetermined jig is inserted into the space between the contact area of the first tip portion13aand third tip portion23aand the insulating sheet14and the contact area is pressed with a predetermined tool from the opposite side from the insulating sheet14.

As is done for the first tip portion13aand third tip portion23athat contact each other, heat is applied by, for example, laser irradiation to the contact area where the second tip portion15aand fourth tip portion25acontact each other, from the opposite side (lower side inFIG.5) of the contact area from the insulating sheet14. By doing so, the second tip portion15aand fourth tip portion25aare melted and solidified at a second welding area2band are thereby welded to each other and a welding portion (2b) is formed. For example, with this technique, the second terminal15of the semiconductor module10A and the fourth terminal25of the capacitor20A are welded to each other. In this example, the heat is applied by laser irradiation to weld (laser weld) the second terminal15and the fourth terminal25to each other. Alternatively, another technique such as ultrasonic welding or friction stir welding may be employed to apply heat in order to weld the second terminal15and the fourth terminal25to each other.

In this connection, in the case of the laser welding, a metal plate made of copper, aluminum, or another may be inserted in the space formed between the contact area where the second tip portion15aand fourth tip portion25acontact each other and the insulating sheet14. Even If there is a gap in the contact area of the second tip portion15aand the fourth tip portion25a, the metal plate is able to prevent the laser from reaching the insulating sheet14through the gap, thereby reducing the risk of damaging the insulating sheet14due to the laser. In the case of the ultrasonic welding, friction stir welding, or another, the welding may be performed while a predetermined jig is inserted into the space between the contact area of the second tip portion15aand fourth tip portion25aand the insulating sheet14and the contact area is pressed with a predetermined tool from the opposite side from the insulating sheet14.

Either the welding of the first terminal13and third terminal23or the welding of the second terminal15and fourth terminal25may be performed first, or both of them may be performed simultaneously.

The semiconductor module10A and capacitor20A are connected to each other as described above, so that the semiconductor device1A as illustrated inFIG.5is obtained.

As described above, the semiconductor module10A has the following configuration: the insulating sheet14, the first terminal13, and the second terminal15all extend to the outside of the resin case11, the first tip portion13aof the first terminal13is spaced apart from the first surface14aof the insulating sheet14, and the second tip portion15aof the second terminal15is spaced apart from the second surface14bof the insulating sheet14. In the capacitor20A, the third terminal23with the third tip portion23aand the fourth terminal25with the fourth tip portion25aare arranged so that the third tip portion23aand fourth tip portion25arespectively contact the first tip portion13aof the first terminal13and the second tip portion15aof the second terminal15in the semiconductor module10A. The first tip portion13aand third tip portion23athat contact each other are then welded to each other by heat applied from the opposite side from the insulating sheet14, and the second tip portion15aand fourth tip portion25athat contact each other are welded to each other by heat applied from the opposite side from the insulating sheet14.

At this time, the first welding area2aof the first tip portion13aand third tip portion23ais spaced apart from the insulating sheet14, and the second welding area2bof the second tip portion15aand fourth tip portion25ais spaced apart from the insulating sheet14. Therefore, heat generated during the formation of the first welding area2aand second welding area2bis prevented from being transferred directly to the insulating sheet14. This reduces the risk of damaging the insulating sheet14due to the heat during the welding. The reduction in the risk of damaging the insulating sheet14leads to preventing changes in the properties of the material of the insulating sheet14, which prevents a deterioration in the insulation performance and accordingly a decrease in the withstand voltage. Thus, the above-described technique makes it possible to implement the high-performance, high-quality semiconductor device1A.

Note that the shapes of the first terminal13and second terminal15illustrated inFIGS.4and5, as well as the shapes of the third terminal23and fourth terminal25illustrated inFIG.5, are not limited to those in the above-described example. As long as the first tip surface13aaof the first tip portion13aand the third tip surface23aaof the third tip portion23aare allowed to contact each other and be welded to each other in a state of being spaced apart from the insulating sheet14and also as long as the second tip surface15aaof the second tip portion15aand the fourth tip surface25aaof the fourth tip portion25aare allowed to contact each other and be welded to each other in a state of being spaced apart from the insulating sheet14, various shapes may be employed for the first terminal13and second terminal15and for the third terminal23and fourth terminal25.

Second Embodiment

FIGS.6A and6Bare views for describing an example of a semiconductor module according to a second embodiment.FIG.6Ais a schematic perspective view illustrating a main part of the example semiconductor module.FIG.6Bis a schematic sectional view illustrating the main part of the example semiconductor module.FIG.6Bis a sectional view taken along a line VI-VI ofFIG.6A, as seen in the arrow direction of the line VI-VI.

The semiconductor module10B illustrated inFIGS.6A and6Bincludes a terminal structure portion12B provided at one side of a resin case11(a frame portion thereof).

The terminal structure portion12B includes a multilayer structure16formed of a first terminal13, an insulating sheet14, and a second terminal15. For example, the first terminal13serves as the N terminal of the semiconductor module10B, and the second terminal15serves as the P terminal of the semiconductor module10B. The first terminal13and second terminal15are connected to an insulated circuit substrate accommodated in the resin case11or respectively to the negative electrode and positive electrode of a semiconductor element or the like accommodated in the resin case11. The first terminal13, insulating sheet14, and second terminal15are stacked in such a manner that the insulating sheet14is interposed between the first terminal13and the second terminal15. The multilayer structure16formed of the first terminal13, insulating sheet14, and second terminal15penetrates through a part of the resin case11, and is placed on a terrace portion17formed in the resin case11. For example, the multilayer structure16is pressed against the terrace portion17by a pressing portion11cof the resin case11.

The insulating sheet14of the terminal structure portion12B is arranged to extend to the outside of the resin case11(beyond an outer edge11bthereof). The insulating sheet14is arranged to extend from inside the resin case11further to the outside than the first terminal13(a first tip portion13athereof) and the second terminal15(a second tip portion15athereof).

The first terminal13of the terminal structure portion12B is arranged to extend to the outside of the resin case11(beyond the outer edge11b). The first terminal13is disposed on the side of the insulating sheet14where a first surface14athereof is located such as to overlap the insulating sheet14in plan view. The first terminal13has the first tip portion13athat is spaced apart from the first surface14aof the insulating sheet14. The first terminal13has a first extending portion13bthat extends from the first tip portion13atoward the resin case11and that contacts the first surface14aof the insulating sheet14. For example, the first terminal13is bent between the first extending portion13band the first tip portion13aso that, when the first terminal13is arranged such that the first extending portion13bcontacts the first surface14aof the insulating sheet14, the first tip portion13ais spaced apart from the first surface14aof the insulating sheet14.

The second terminal15of the terminal structure portion12B is arranged to extend to the outside of the resin case11(beyond the outer edge11b). The second terminal15is disposed on the side of the insulating sheet14where the second surface14bis located such as to overlap the insulating sheet14and first terminal13in plan view. The second terminal15has the second tip portion15athat is spaced apart from the second surface14bof the insulating sheet14. The second terminal15has a second extending portion15bthat extends from the second tip portion15atoward the resin case11and that contacts the second surface14bof the insulating sheet14. For example, the second terminal15is bent between the second extending portion15band the second tip portion15aso that, when the second terminal15is arranged such that the second extending portion15bcontacts the second surface14bof the insulating sheet14, the second tip portion15ais spaced apart from the second surface14bof the insulating sheet14.

A part (referred to as a “first portion”) of the first extending portion13bof the first terminal13that is a portion extending from the first tip portion13atoward the resin case11, a part (referred to as a “second portion”) of the second extending portion15bof the second terminal15that is a portion extending from the second tip portion15atoward the resin case11, and a part (referred to as a “third portion”) of the insulating sheet14sandwiched between the first portion and the second portion are placed on the terrace portion17formed in the resin case11. The first portion, second portion, and third portion are pressed against the terrace portion17by the pressing portion11cof the resin case11.

The semiconductor module10B differs from the semiconductor module10A described earlier in the first embodiment in that the semiconductor module10B includes the terminal structure portion12B with the first terminal13and second terminal15whose tip portions have different shapes from those described in the first embodiment.

The semiconductor module10B configured as described above is connected to a capacitor, so that a semiconductor device is obtained.

FIG.7is a view for describing an example of a semiconductor device according to the second embodiment.FIG.7is a schematic sectional view illustrating a main part of the example semiconductor device.

The semiconductor device1B illustrated inFIG.7includes the semiconductor module10B and a capacitor20B.

The capacitor20B includes a resin case21that accommodates therein a capacitor element. At one side of the resin case21, a terminal structure portion22B is provided, which is connected to the accommodated capacitor element and is used to connect the capacitor20B to the semiconductor module10B provided external to the capacitor20B. The terminal structure portion22B of the capacitor20B is arranged at a position corresponding to the terminal structure portion12B of the semiconductor module10B. A plurality of terminal structure portions22B may be provided at the one side of the resin case21.

The terminal structure portion22B of the capacitor20B includes a third terminal23, an insulating sheet24, and a fourth terminal25. For example, the third terminal23serves as the N terminal of the capacitor20B, and the fourth terminal25serves as the P terminal of the capacitor20B. The third terminal23and fourth terminal25are connected respectively to the negative electrode and positive electrode of the capacitor element accommodated in the resin case21.

In the terminal structure portion22B, the third terminal23has one end connected to the resin case21, and is bent so that the other end thereof extends toward the outside of the resin case21(beyond an outer edge21athereof). The fourth terminal25has one end connected to the resin case21and is bent so that the other end thereof extends to the outside of the resin case21. The one end of the fourth terminal25is located outside the one end of the third terminal23on the resin case21. The insulating sheet24has one end connected to the resin case21at a position between the one end of the third terminal23and the one end of the fourth terminal25, and has flexibility so as to be bent toward the fourth terminal25.

The third terminal23of the terminal structure portion22B has a third tip portion23aand a third extending portion23bextending from the third tip portion23atoward the resin case21. The third tip portion23ais more recessed than the third extending portion23b. The fourth terminal25of the terminal structure portion22B has a fourth tip portion25aand a fourth extending portion25bextending from the fourth tip portion25atoward the resin case21. The fourth tip portion25ais more recessed than the fourth extending portion25b. For example, the third terminal23and fourth terminal25of the terminal structure portion22B have shapes like those in which the third tip portion23aof the third terminal23and the fourth tip portion25aof the fourth terminal25in the terminal structure portion22A described earlier in the first embodiment are further extended to the outside of the resin case21.

In connecting the semiconductor module10B and the capacitor20B to each other, the semiconductor module10B and the capacitor20B are arranged such that their terminal structure portion12B and terminal structure portion22B face each other. At this time, the third tip portion23aof the third terminal23of the capacitor20B is inserted and arranged in the space between the first surface14aof the insulating sheet14and the first tip portion13aof the first terminal13spaced apart from the first surface14ain the semiconductor module10B. At the same time, the fourth tip portion25aof the fourth terminal25of the capacitor20B is inserted and arranged in the space between the second surface14bof the insulating sheet14and the second tip portion15aof the second terminal15spaced apart from the second surface14bin the semiconductor module10B.

The third terminal23and fourth terminal25are provided in advance in the capacitor20B so that, when the third tip portion23aand fourth tip portion25aare arranged respectively between the first surface14aof the insulating sheet14and the first tip portion13aand between the second surface14band the second tip portion15aas described above, the third tip portion23acontacts the first tip portion13aand the fourth tip portion25acontacts the second tip portion15a. Alternatively, the first terminal13and second terminal15are provided in advance in the semiconductor module10B so that, when the third tip portion23aand fourth tip portion25aare arranged respectively between the first surface14aof the insulating sheet14and the first tip portion13aand between the second surface14band the second tip portion15a, the first tip portion13acontacts the third tip portion23aand the second tip portion15acontacts the fourth tip portion25a.

The third tip portion23ais arranged between the first surface14aand the first tip portion13ain a state of being spaced apart from the first surface14aof the insulating sheet14and contacting the first tip portion13aof the first terminal13. The fourth tip portion25ais arranged between the second surface14band the second tip portion15ain a state of being spaced apart from the second surface14bof the insulating sheet14and contacting the second tip portion15aof the second terminal15.

Then, heat is applied by, for example, laser irradiation to the first tip portion13aarranged over the insulating sheet14with the third tip portion23atherebetween, from the side where the first tip portion13ais located (from the upper side inFIG.7). As a result, the first tip portion13aand third tip portion23aare melted and solidified at a first welding area2aand are thereby welded to each other. For example, with this technique, the first terminal13of the semiconductor module10B and the third terminal23of the capacitor20B are welded to each other. In this example, the heat is applied by laser irradiation to weld (laser weld) the first terminal13and the third terminal23to each other. Alternatively, another technique such as ultrasonic welding or friction stir welding may be employed to apply heat from the side where the first tip portion13ais located in order to weld the first terminal13and the third terminal23to each other.

In this connection, in the case of the laser welding, a metal plate made of copper, aluminum, or another may be inserted in the space formed between the third tip portion23aand the insulating sheet14. Even if the laser irradiation causes such melting that penetrates through the third tip portion23a, the metal plate is able to prevent the melting from reaching the insulating sheet14, which reduces the risk of damaging the insulating sheet14. In the case of another technique such as ultrasonic welding or friction stir welding, the welding is performed while a predetermined jig is inserted into the space between the third tip portion23aand the insulating sheet14and the first tip portion13aand third tip portion23aare pressed with a predetermined tool from the side where the first tip portion13ais located.

Similarly, heat is applied by, for example, laser irradiation to the second tip portion15aarranged over the insulating sheet14with the fourth tip portion25atherebetween, from the side where the second tip portion15ais located (from the lower side inFIG.7). As a result, the second tip portion15aand fourth tip portion25aare melted and solidified at a second welding area2band are thereby welded to each other. For example, with this technique, the second terminal15of the semiconductor module10B and the fourth terminal25of the capacitor20B are welded to each other. In this example, the heat is applied by laser irradiation to weld (laser weld) the second terminal15and the fourth terminal25to each other. Alternatively, another technique such as ultrasonic welding or friction stir welding may be employed to apply heat from the side where the second tip portion15ais located in order to weld the second terminal15and the fourth terminal25to each other.

In this connection, in the case of the laser welding, a metal plate made of copper, aluminum, or another may be inserted in the space formed between the fourth tip portion25aand the insulating sheet14. Even if the laser irradiation causes such melting that penetrates through the fourth tip portion25a, the metal plate is able to prevent the melting from reaching the insulating sheet14, which reduces the risk of damaging the insulating sheet14. In the case of another technique such as ultrasonic welding or friction stir welding, the welding is performed while a predetermined jig is inserted into the space between the fourth tip portion25aand the insulating sheet14and the second tip portion15aand fourth tip portion25aare pressed with a predetermined tool from the side where the second tip portion15ais located.

Either the welding of the first terminal13and third terminal23or the welding of the second terminal15and fourth terminal25may be performed first, or both of them may be performed simultaneously.

The semiconductor module10B and capacitor20B are connected to each other as described above, so that the semiconductor device1B as illustrated inFIG.7is obtained.

As described above, the semiconductor module10B has the following configuration: the insulating sheet14, first terminal13, and second terminal15all extend to the outside of the resin case11, the first tip portion13aof the first terminal13is spaced apart from the first surface14aof the insulating sheet14, and the second tip portion15aof the second terminal15is spaced apart from the second surface14bof the insulating sheet14. In the capacitor20B, the third terminal23with the third tip portion23aand the fourth terminal25with the fourth tip portion25aare arranged so that the third tip portion23ais inserted between the first tip portion13aof the first terminal13and the insulating sheet14in the semiconductor module10B and the fourth tip portion25ais inserted between the second tip portion15aof the second terminal15and the insulating sheet14in the semiconductor module10B. The third terminal23and fourth terminal25of the capacitor20B are inserted respectively between the first tip portion13aand the insulating sheet14and between the second tip portion15aand the insulating sheet14in a state of being spaced apart from the insulating sheet14. Then, the first tip portion13aand third tip portion23aare welded to each other by heat applied from the opposite side from the insulating sheet14, and the second tip portion15aand fourth tip portion25aare welded to each other by heat applied from the opposite side from the insulating sheet14.

At this time, the first welding area2aof the first tip portion13aand third tip portion23ais spaced apart from the insulating sheet14, and the second welding area2bof the second tip portion15aand fourth tip portion25ais spaced apart from the insulating sheet14. Therefore, heat generated during the formation of the first welding area2aand second welding area2bis prevented from being transferred directly to the insulating sheet14. This reduces the risk of damaging the insulating sheet14due to the heat during the welding. The reduction in the risk of damaging the insulating sheet14leads to preventing changes in the properties of the material of the insulating sheet14, which prevents a deterioration in the insulation performance and accordingly a decrease in the withstand voltage. Thus, the above-described technique makes it possible to implement the high-performance, high-quality semiconductor device1B.

Note that the shapes of the first terminal13and second terminal15illustrated inFIGS.6and7, as well as the shapes of the third terminal23and fourth terminal25illustrated inFIG.7, are not limited to those in the above-described example. As long as the third tip portion23ais allowed to be arranged between the first tip portion13aand the insulating sheet14and be welded to the first tip portion13ain a state of being spaced apart from the insulating sheet14and also as long as the fourth tip portion25ais allowed to be arranged between the second tip portion15aand the insulating sheet14and be welded to the second tip portion15ain a state of being spaced apart from the insulating sheet14, various shapes may be employed for the first terminal13and second terminal15and for the third terminal and fourth terminal25.

Third Embodiment

A third embodiment will be described, which provides modifications of the above-described semiconductor module10A.

FIGS.8A and8Bare views for describing examples of a semiconductor module according to the third embodiment.FIGS.8A and8Bare schematic perspective views each illustrating a main part of an example semiconductor module or the like.

The semiconductor module10Aa illustrated inFIG.8Adiffers from the semiconductor module10A described earlier in the first embodiment (FIGS.4A and4B) in that the pressing portion11c, which presses the multilayer structure16formed of the first terminal13, insulating sheet14, and second terminal15against the terrace portion17of the resin case11(FIGS.8A and4B), has a larger width W1(>W0).

In the multilayer structure16, the first terminal13, insulating sheet14, and second terminal15are all arranged to extend to the outside of the resin case11beyond the outer edge11bthereof. Therefore, if the width W0of the pressing portion11cthat presses the multilayer structure16is relatively small, force generated by vibrations or other factors after connection with the capacitor20A or the like may create separation in the multilayer structure16, which increases the risk of damaging the above-described first welding area2aand second welding area2b. By contrast, the use of the pressing portion11cwith the relatively large width W1to press the multilayer structure16effectively reduces the risk of causing separation in the multilayer structure16due to vibrations or others. This results in effectively reducing the risk of damaging the above-described first welding area2aand second welding area2b.

In addition, the semiconductor module10Ab illustrated inFIG.8Bdiffers from the semiconductor module10A (FIGS.4A and4B) described earlier in the first embodiment in that ribs11efor pressing the multilayer structure16against the terrace portion17are provided on side walls11dsurrounding the terrace portion17of the resin case11(FIGS.8A and4B) where the multilayer structure16formed of the first terminal13, insulating sheet14, and second terminal15is arranged.

The ribs11eprovided in the semiconductor module10Ab are one example of the pressing portion designed to press the multilayer structure16against the terrace portion17. As in the above-described case, the use of these ribs11eas the pressing portion effectively reduces the risk of causing separation due to vibration or other factors in the multilayer structure16formed of the first terminal13, insulating sheet14, and second terminal15, which are arranged to extend to the outside of the resin case11beyond the outer edge11bthereof, which results in effectively reducing the risk of damaging the above-described first welding area2aand second welding area2b.

In this connection, the pressing portion11cwith a relatively small width W0, as illustrated inFIG.8B, may be combined with the ribs11eas illustrated inFIG.8Bto press the multilayer structure16. Alternatively, the pressing portion11cwith the relatively large width W1, as illustrated inFIG.8A, may be combined with the ribs11eas illustrated inFIG.8Bto press the multilayer structure16.

This embodiment has described the modifications of, as an example, the semiconductor module10A described earlier in the first embodiment, one modification being that the width of the pressing portion11cis changed to the relatively large width W1(FIG.8A), the other modification being that the ribs11eare added (FIG.8B). Furthermore, the same modifications are also possible for the semiconductor module10B described earlier in the second embodiment.

Fourth Embodiment

A fourth embodiment will be described, which is an example of a method of manufacturing the above-described semiconductor device1A and the like.

FIG.9is a view for describing an example of a semiconductor device manufacturing method according to the fourth embodiment.

For example, in manufacturing the semiconductor device1A described earlier in the first embodiment (FIG.5), the semiconductor module10A is first prepared (step S1), and the capacitor20A to be connected to the semiconductor module10A is also prepared (step S2). Note that the order of steps S1and S2is interchangeable. Then, the semiconductor module10A and capacitor20A are arranged such that their terminal structure portion12A and terminal structure portion22A face each other, and then the first terminal13of the semiconductor module10A is connected to the third terminal23of the capacitor20A (step S3). Then, the second terminal15of the semiconductor module10A is connected to the fourth terminal25of the capacitor20A (step S4). Steps S3and S4may be performed in any order or simultaneously.

In the manufacturing of the semiconductor device1A (FIG.5), in the first connection step (step S3) of connecting the first tip portion13ato the third tip portion23a, the first tip portion13aand third tip portion23aare connected to each other in a state of being spaced apart from the first surface14aof the insulating sheet14. In the second connection step (step S4) of connecting the second tip portion15ato the fourth tip portion25a, the second tip portion15aand fourth tip portion25aare connected to each other in a state of being spaced apart from the second surface14bof the insulating sheet14. At this time, the tip surface of the first tip portion13aand the tip surface of the third tip portion23aare brought into contact with each other, and heat is applied by laser irradiation or the like from the opposite side from the insulating sheet14, thereby welding the first terminal13and the third terminal23to each other. Similarly, the tip surface of the second tip portion15aand the tip surface of the fourth tip portion25aare brought into contact with each other, and heat is applied by laser irradiation or the like from the opposite side from the insulating sheet14, thereby welding the second terminal15and the fourth terminal25to each other.

With this method, the semiconductor device1A as described earlier in the first embodiment is manufactured. Note that the method may be employed for the semiconductor modules configured as described earlier in the third embodiment, in place of the semiconductor module10A.

In the case of manufacturing the semiconductor device1B (FIG.7) as described earlier in the second embodiment, the semiconductor module10B is first prepared (step S1), and the capacitor20B to be connected to the semiconductor module10B is also prepared (step S2). In this connection, the order of steps S1and S2is interchangeable. Then, the semiconductor module10B and the capacitor20B are arranged such that their terminal structure portion12B and terminal structure portion22B face each other, and the first terminal13of the semiconductor module10B is connected to the third terminal23of the capacitor20B (step S3). Then, the second terminal15of the semiconductor module10B is connected to the fourth terminal25of the capacitor20B (step S4). Steps S3and S4may be performed in any order or simultaneously.

In the manufacturing of the semiconductor device1B (FIG.5), in the first connection step (step S3) of connecting the first tip portion13ato the third tip portion23a, the first tip portion13aand the third tip portion23aare connected to each other in a state of being spaced apart from the first surface14aof the insulating sheet14. In the second connection step (step S4) of connecting the second tip portion15ato the fourth tip portion25a, the second tip portion15aand the fourth tip portion25aare connected to each other in a state of being spaced apart from the second surface14bof the insulating sheet14. At this time, the third tip portion23ais arranged between the first surface14aof the insulating sheet14and the first tip portion13a, and heat is applied by laser irradiation or the like from the opposite side of the first tip portion13afrom the insulating sheet14, thereby welding the first terminal13and the third terminal23to each other. The fourth tip portion25ais arranged between the second surface14bof the insulating sheet14and the second tip portion15a, and heat is applied by laser irradiation or the like from the opposite side of the second tip portion15afrom the insulating sheet14, thereby welding the second terminal15and the fourth terminal25to each other.

With the above method, the semiconductor device1B as described earlier in the second embodiment is manufactured. In this connection, this method may be employed for the semiconductor modules configured as described earlier in the third embodiment, in place of the semiconductor module10B.

According to one aspect, it is possible to reduce the risk of damaging an insulating sheet during the welding of a terminal of a semiconductor module.