JP6610101B2 - Semiconductor module - Google Patents

Description

  The present invention relates to a semiconductor module, and more particularly to a power semiconductor module including a block conductor that contributes to heat dissipation of a power semiconductor element.

  A power semiconductor module is a semiconductor device used for controlling and supplying power. In a power semiconductor module, a large amount of electric power is often input, and the power semiconductor element tends to generate heat and become high temperature. Therefore, the power semiconductor module requires a device for heat dissipation. Japanese Patent Laid-Open No. 2001-308237 (Patent Document 1) proposes an example of a power semiconductor module with such a device.

  FIG. 15 is a cross-sectional view of a power semiconductor module 200 described in Patent Document 1. The power semiconductor module 200 includes a power semiconductor element 201A, a semiconductor element 201B, a first block conductor 202A, a second block conductor 202B, a first conductor 203, a second conductor 206, and a third conductor A conductor 209 and a wire 210 are provided.

  The power semiconductor element 201A and the first block conductor 202A, and the semiconductor element 201B and the second block conductor 202B are joined together by a joining material S such as solder. The power semiconductor element 201A and the semiconductor element 201B and the second conductor 206, and the first block conductor 202A and the second block conductor 202B and the first conductor 203 are also bonded by the bonding material S in the same manner. The wire 210 connects the power semiconductor element 201 </ b> A and the third conductor 209.

  In the power semiconductor module 200, the heat generated from the power semiconductor element 201A is dissipated from the lower surface of the power semiconductor element 201A to the outside through the second conductor 206. At the same time, the heat generated from the power semiconductor element 201A is dissipated from the upper surface of the power semiconductor module 200A to the outside through the first block conductor 202A and the first conductor 203.

  With this configuration, the power semiconductor module 200 can efficiently dissipate heat generated in the power semiconductor element 201A.

JP 2001-308237 A

  By the way, there is an electrode (not shown) connected to the wire 210 on the power semiconductor element 201A. That is, the first block conductor 202A needs not to contact the wire 210 and its electrode. Therefore, the cross-sectional area of the first block conductor 202A is made smaller than the area of the main surface of the power semiconductor element 201A in the thickness direction (direction orthogonal to the main surface) of the first block conductor 202A.

  On the other hand, with the above structure, in the power semiconductor module 200, it is considered that the amount of heat dissipated from the upper surface of the power semiconductor element 201A is small. Therefore, there is a possibility that the heat generated in the power semiconductor element 201A cannot be efficiently dissipated.

  Accordingly, an object of the present invention is to provide a semiconductor module that can efficiently dissipate heat generated in a semiconductor element (particularly, a power semiconductor element).

  In the present invention, the shape of the block conductor can be improved in order to efficiently dissipate heat generated in the semiconductor element (particularly, the power semiconductor element).

  A semiconductor module according to the present invention includes a semiconductor element including a first electrode and a second electrode on one main surface and a third electrode on the other main surface, and one main surface and the other main surface parallel to each other; And a block conductor having a side surface connecting the one main surface and the other main surface, a first conductor, a second conductor, a third conductor, and a connecting member.

  One main surface of the first conductor and the block conductor, the first electrode and the other main surface of the block conductor, and the third electrode and the second conductor are bonded by a bonding material. The second electrode and the third conductor are connected via a connection member.

  When the direction perpendicular to the one main surface of the block conductor is taken as the thickness direction of the block conductor, the maximum cross-sectional area of the block conductor in the thickness direction is larger than the area of the one main surface of the semiconductor element. The block conductor includes a space formed so as not to contact the second electrode and the connecting member.

  In the above semiconductor module, since the connecting member passes through the space formed so that the block conductor is not in contact with the second electrode and the connecting member, the other of the first electrode and the block conductor is used. The bonding area with the main surface can be increased. Since the maximum cross-sectional area of the block conductor in the thickness direction is larger than the area of the one main surface of the semiconductor element, the thermal resistance in the block conductor is reduced, and the amount of heat dissipated from the upper surface of the semiconductor element can be increased. . Therefore, the heat generated in the semiconductor element can be efficiently dissipated.

  The semiconductor module according to the present invention preferably has the following features. In other words, the space is a recess formed so as to be exposed to at least one of the side surfaces of the block conductor and one main surface and the other main surface of the block conductor.

  In the semiconductor module described above, the block conductor can be reliably brought into non-contact with the second electrode and the connection member. Moreover, a recessed part can be easily formed in a block conductor.

  The semiconductor module according to the present invention preferably includes the following features. That is, the space is a recess formed so as to be exposed to at least one of the side surfaces of the block conductor and the other main surface of the block conductor and not to be exposed to one main surface of the block conductor.

  In the semiconductor module described above, the volume of the concave portion occupied in the block conductor is small, and the thermal resistance of the block conductor is further reduced. Therefore, the amount of heat dissipated from the upper surface of the semiconductor element can be further increased. Therefore, the heat generated in the semiconductor element can be dissipated more efficiently.

  The semiconductor module according to the present invention and preferred embodiments thereof preferably have the following features. That is, the first conductor and one main surface of the block conductor are bonded by the first bonding material, the first electrode and the other main surface of the block conductor are bonded by the second bonding material, and the third electrode And the second conductor are joined by a third joining material.

  At least one of the first bonding material and the second bonding material is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, The bonding material 3 is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, or solidified solder.

  In the above-described semiconductor module, at least one of the first bonding material and the second bonding material is silver, copper, gold, or an alloy of at least two kinds of metals selected from them. For this reason, heat from the upper surface of the semiconductor element can be easily transferred to the first conductor. Therefore, the heat generated in the semiconductor element can be dissipated more efficiently.

  A preferred embodiment of the semiconductor module according to the present invention preferably has the following features. That is, the third bonding material is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them. Further, the second conductor includes an annular recess on the surface to be joined to the semiconductor element. When the annular recess provided in the second conductor and the semiconductor element are viewed from the thickness direction of the block conductor, the outer peripheral edge of the other main surface of the semiconductor element is the annular conductor provided in the second conductor. It is located between the inner periphery and the outer periphery of the recess.

  A sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from the third bonding material is provided between the third electrode and the second conductor. It is formed by sintering in the state of interposing the metal nanoparticle paste. In other words, the third bonding material does not melt and become liquid in the formation process. Therefore, for example, when the supply amount of the above-mentioned metal nanoparticle paste is large and the adhesion amount to the side surface of the semiconductor element is increased, it does not melt and flow down like solder and remains attached. Therefore, the first electrode and the third electrode of the semiconductor element are electrically close to each other, and the insulating property may be deteriorated.

  On the other hand, in the semiconductor module described above, excess of the metal nanoparticle paste moves to the annular recess provided in the second conductor, so that the amount of adhesion to the side surface of the semiconductor element is reduced. Can do. Therefore, the first electrode and the third electrode of the semiconductor element can be prevented from being in electrical proximity, and high insulation can be maintained.

  A preferred embodiment of the semiconductor module according to the present invention preferably includes the following features. That is, the second bonding material is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them. Moreover, the block conductor is provided with a convex portion on the other main surface side. When the block conductor and the semiconductor element are viewed from the thickness direction of the block conductor, the outer peripheral edge of the one main surface of the semiconductor element is the outer peripheral edge of the convex portion provided in the block conductor and the space described above in the block conductor. Is located between the outer peripheral edge of the other main surface of the block conductor when it is assumed that is not provided.

  When the second bonding material is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, there is a concern similar to the above. On the other hand, in the semiconductor module described above, an excess of the metal nanoparticle paste moves to the side surface of the convex portion, so that the amount of adhesion to the side surface of the semiconductor element can be reduced. Therefore, the first electrode and the third electrode of the semiconductor element can be prevented from being in electrical proximity, and high insulation can be maintained.

  Moreover, when the 2nd conductor is provided with the cyclic | annular recessed part, excess thing moves to a cyclic | annular recessed part among said metal nanoparticle paste used as the 3rd joining material. That is, the amount of adhesion to the side surface of the semiconductor element can be further reduced by both effects. Therefore, the first electrode and the third electrode of the semiconductor element can be reliably avoided from being in electrical proximity, and high insulation can be reliably maintained.

  The embodiment of the semiconductor module according to the present invention preferably includes the following features. That is, the block conductor includes one main surface and the other main surface that are parallel to each other. In this case, since the block conductor has a flat plate shape, the block conductor, the semiconductor module, and each conductor can be easily joined.

  In the semiconductor module according to the present invention, the junction area between the first electrode and the other main surface of the block conductor can be increased. And the thermal resistance in a block conductor becomes small and the amount of heat dissipation from the upper surface of a semiconductor element can be enlarged. Therefore, the heat generated in the semiconductor element (particularly, the power semiconductor element) can be efficiently dissipated.

FIG. 3 is a cross-sectional view of the power semiconductor module 100 that is the first embodiment of the semiconductor module according to the present invention, taken along the line A3-A3 shown in FIG. FIG. 2 is a cross-sectional view of the power semiconductor module 100 taken along the line A1-A1 shown in FIG. 1 and a cross section taken along a line A2-A2 shown in FIG. It is arrow sectional drawing in the cut surface containing A6-A6 line shown in FIG. 4 of power semiconductor module 100A which is 2nd Embodiment of the semiconductor module which concerns on this invention. FIG. 4 is a cross-sectional view of the power semiconductor module 100A taken along an arrowed line including a cut surface including an A4-A4 line and a cut surface including an A5-A5 line illustrated in FIG. 3. It is arrow sectional drawing in the cut surface containing the A9-A9 line | wire shown in FIG. 6 of power semiconductor module 100B which is 3rd Embodiment of the semiconductor module which concerns on this invention. FIG. 6 is a cross-sectional view of the power semiconductor module 100B taken along an arrow line including a cut surface including an A7-A7 line illustrated in FIG. 5 and a cut surface including an A8-A8 line. It is arrow sectional drawing in the cut surface containing the A12-A12 line | wire shown in FIG. 8 of power semiconductor module 100C which is 4th Embodiment of the semiconductor module which concerns on this invention. FIG. 8 is a cross-sectional view of the power semiconductor module 100 </ b> C taken along an arrowed line including a cut surface including an A <b> 10-A <b> 10 line illustrated in FIG. FIG. 4 is a cross-sectional view corresponding to the cross-sectional view taken along the arrow in FIG. 1 for explaining the possibility that the second bonding material S2 and the third bonding material S3 come into contact with each other and short-circuit in the power semiconductor module. A power semiconductor module 100D, which is a fifth embodiment of the semiconductor module according to the present invention, includes a cross-sectional view corresponding to a cross-sectional view taken in the direction of the arrow in FIG. 1, and an outer peripheral edge of the power semiconductor element 1 and a second conductor 6. It is a schematic diagram for demonstrating the positional relationship with the annular recessed part T1 which is. A power semiconductor module 100E, which is a sixth embodiment of the semiconductor module according to the present invention, is a cross-sectional view corresponding to the cross-sectional view taken in the direction of the arrow in FIG. It is a schematic diagram for demonstrating the positional relationship with the part T2. It is sectional drawing equivalent to the arrow sectional drawing of FIG. 1 of the power semiconductor module 100F which is 7th Embodiment of the semiconductor module which concerns on this invention. It is sectional drawing equivalent to arrow sectional drawing of FIG. 1 of the power semiconductor module 100G which is 8th Embodiment of the semiconductor module which concerns on this invention. It is sectional drawing equivalent to arrow sectional drawing of FIG. 1 of the power semiconductor module 100H which is 9th Embodiment of the semiconductor module which concerns on this invention. It is sectional drawing of the power semiconductor module 200 of background art.

  Embodiments of the present invention will be described below to describe the features of the present invention in more detail.

-First Embodiment of Semiconductor Module-
A power semiconductor module 100 which is a first embodiment of a semiconductor module according to the present invention will be described with reference to FIGS. As a semiconductor module to which the present invention is applied, for example, a power semiconductor module used for an inverter for driving electrical equipment such as a power steering mechanism of an automobile, or an inverter for driving a motor for an electric vehicle and a hybrid vehicle. Examples thereof include power semiconductor modules used, but are not limited thereto.

  FIG. 1 is a cross-sectional view of the power semiconductor module 100 taken along an arrowed line including a line A3-A3 shown in FIG. FIG. 2A is a cross-sectional view of the power semiconductor module 100 taken along the line A1-A1 shown in FIG. FIG. 2B is a cross-sectional view of the power semiconductor module 100 taken along the line A2-A2 shown in FIG.

  The power semiconductor module 100 includes a power semiconductor element 1, a block conductor 2, a first conductor 3, a second conductor 6, a third conductor 9, and a connection member 10.

  The power semiconductor element 1 includes a first electrode 1F and a second electrode 1S on one main surface, and a third electrode 1T on the other main surface. As the power semiconductor element 1, for example, a power MOSFET (metal oxide semiconductor field effect transistor) and an IGBT (insulated gate bipolar transistor) can be used. When the power semiconductor element 1 is a power MOSFET, the first electrode 1F, the second electrode 1S, and the third electrode 1T are an emitter electrode, a base electrode, and a collector electrode, respectively. On the other hand, when the power semiconductor element 1 is a power MOSFET, it becomes a source electrode, a gate electrode, and a drain electrode, respectively.

  In this embodiment, the block conductor 2 includes one main surface and the other main surface that are parallel to each other, and a side surface that connects the one main surface and the other main surface. That is, the shape of the block conductor 2 is a rectangular parallelepiped, except for the concave portions described later, and one main surface is the upper surface of the block conductor 2 and the other main surface is the lower surface.

  The shape of the block conductor 2 is not limited to a rectangular parallelepiped, except for a concave portion to be described later, and may have any shape such as a truncated pyramid, a cylinder, and a truncated cone. The one main surface and the other main surface of the block conductor 2 are not parallel to each other. For example, the other main surface may be inclined with respect to the one main surface, or the one main surface of the curved surface and the other main surface of the flat surface A combination with a surface may be used. As the block conductor 2, aluminum or an alloy thereof, copper and an alloy thereof, and silver and an alloy thereof, which are metals having high electric conductivity and thermal conductivity, can be preferably used.

  In this embodiment, the first conductor 3 is formed on one main surface of the first insulating layer 4. A first heat radiating plate 5 for further improving the heat radiation efficiency is provided on the other main surface of the first insulating layer 4. However, the first insulating layer 4 and the first heat radiating plate 5 may not be necessary depending on the design of the power semiconductor module, and thus are not essential components in the present invention.

  In this embodiment, the second conductor 6 is formed on one main surface of the second insulating layer 7. A second heat radiating plate 8 for further improving the heat radiation efficiency is provided on the other main surface of the second insulating layer 7. The second insulating layer 7 and the second heat radiating plate 8 are not essential components in the present invention, like the first insulating layer 4 and the first heat radiating plate 5.

  The first insulating layer 4 and the second insulating layer 7 are made of, for example, a resin material in which a glass or ceramic filler is dispersed in an epoxy resin, glass ceramic, aluminum oxide, aluminum nitride, silicon nitride, or the like. The ceramic material can be appropriately selected according to the design of the power semiconductor module. Moreover, it is preferable that the 1st heat sink 5 and the 2nd heat sink 8 use aluminum or its alloy, copper and its alloy, and silver and its alloy which are metals with big heat conductivity.

  In this embodiment, the third conductor 9 is formed on one main surface of the second insulating layer 7. The third conductor 9 is connected to the second electrode 1 </ b> S of the power semiconductor element 1 through the connection member 10. As the first conductor 3, the second conductor 6, and the third conductor 9, it is preferable to use copper or a copper alloy.

  The connecting member 10 is a wire in this embodiment. The connecting member 10 may be a clip (plate member) as shown in an eighth embodiment (FIG. 13) described later.

  The first conductor 3 and one main surface of the block conductor 2 are joined by a first joining material S1, and both are electrically and thermally connected. The first electrode 1F and the other main surface of the block conductor 2 are joined by the second joining material S2, and are similarly electrically and thermally connected. The third electrode 1T and the second conductor 6 are joined by a third joining material S3, and are similarly electrically and thermally connected.

  Examples of the first bonding material S1, the second bonding material S2, and the third bonding material S3 include solidified solder, silver, copper, gold, or an alloy of at least two kinds of metals selected from them. A sintered body of metal nanoparticles such as particles and a conductive resin material can be used. As will be described later, in order to improve the dissipation of heat from the power semiconductor element 1, at least one of the first bonding material S1, the second bonding material S2, and the third bonding material S3 is heated. It is preferable to use a sintered body of nanoparticles of silver, copper, gold having excellent conductivity, or an alloy of at least two kinds of metals selected from them. The first bonding material S1, the second bonding material S2, and the third bonding material S3 may be the same bonding material. However, as will be described later, an optimum bonding material may be properly used at a bonding portion. preferable.

  When the direction perpendicular to the one main surface of the block conductor 2 is the thickness direction of the block conductor 2, the maximum cross-sectional area of the block conductor 2 in the thickness direction is larger than the area of the one main surface of the power semiconductor element 1. Yes. Further, as shown in FIG. 2B, the block conductor 2 includes a space SP1 formed so as not to contact the second electrode 1S and the connection member 10.

  In this embodiment, the space SP1 includes a side surface facing the side where the third conductor 9 of the block conductor 2 exists, and one main surface, as shown in FIGS. And a groove-shaped recess formed so as to be exposed to the other main surface. Further, the block conductor 2 is a rectangular parallelepiped when considered excluding the space SP1 as described above, and the maximum cross-sectional area of the block conductor 2 is equal to the areas of the one main surface and the other main surface.

  Further, as shown in FIG. 2A, the maximum cross-sectional area of the block conductor 2 represented by the area of the hatched portion (concave octagon) is a power semiconductor element represented by the area of the region within the outer dotted line. 1 is larger than the area of one main surface.

  In the power semiconductor module 100, as shown in FIG. 1 and FIG. 2 (A), since the connecting member 10 passes through the space SP1 formed in the block conductor 2, the first electrode 1F and the block conductor The joining area with the other main surface of 2 can be increased. Since the maximum cross-sectional area of the block conductor 2 in the thickness direction is larger than the area of the one main surface of the power semiconductor element 1, the thermal resistance in the block conductor 2 is reduced, and the amount of heat dissipated from the upper surface of the power semiconductor element 1 Can be increased. Therefore, the heat generated in the power semiconductor element 1 can be efficiently dissipated.

-Second Embodiment of Semiconductor Module-
A power semiconductor module 100A, which is a second embodiment of the semiconductor module according to the present invention, will be described with reference to FIGS.

  FIG. 3 is a cross-sectional view of the power semiconductor module 100A as viewed in the direction of the section including the line A6-A6 shown in FIG. FIG. 4A is a cross-sectional view of the power semiconductor module 100A taken along the line A4-A4 shown in FIG. FIG. 4B is a cross-sectional view of the power semiconductor module 100A taken along an arrowed line including a line A5-A5 shown in FIG.

  The power semiconductor module 100A is different from the power semiconductor module 100 according to the first embodiment in the formation position of the space SP1. Since other than that is common with the power semiconductor module 100, description of a common location is abbreviate | omitted.

  As shown in FIGS. 4A and 4B, the space SP1 includes a side surface facing the side where the third conductor 9 of the block conductor 2 exists, a side surface connected to one side thereof, The groove-shaped recessed part formed so that it might be exposed to a surface and the other main surface may be sufficient.

  Even in this case, as shown in FIG. 4A, the maximum cross-sectional area of the block conductor 2 represented by the area of the hatched portion (concave hexagon) is the power represented by the area of the region within the outer dotted line. It is larger than the area of one main surface of the semiconductor element 1.

  Also in the power semiconductor module 100A, as shown in FIG. 4A, since the connecting member 10 passes through the space SP1 formed in the block conductor 2, the other main of the first electrode 1F and the block conductor 2 is used. The bonding area with the surface can be increased. Therefore, the same effect as that of the power semiconductor module 100 can be obtained.

-Third Embodiment of Semiconductor Module-
A power semiconductor module 100B, which is a third embodiment of the semiconductor module according to the present invention, will be described with reference to FIGS.

  FIG. 5 is a cross-sectional view of the power semiconductor module 100B taken along the line A9-A9 shown in FIG. FIG. 6A is a cross-sectional view of the power semiconductor module 100B taken along the line A7-A7 shown in FIG. FIG. 6B is a cross-sectional view of the power semiconductor module 100B taken along the line A8-A8 shown in FIG.

  Similarly to the power semiconductor module 100A, the power semiconductor module 100B is different from the power semiconductor module 100 according to the first embodiment in the formation position of the space SP1. Since other than that is common with the power semiconductor module 100, description of a common location is abbreviate | omitted.

  As shown in FIGS. 5 and 6A and 6B, the space SP1 is exposed to the side surface of the block conductor 2 facing the side where the third conductor 9 exists and the other main surface. It may be a groove-shaped recess formed.

  Even in this case, as shown in FIG. 6A, the maximum cross-sectional area of the block conductor 2 represented by the area of the hatched portion (rectangle) is the power semiconductor element 1 represented by the area of the region within the outer dotted line. It is larger than the area of one main surface.

  Also in the power semiconductor module 100B, as shown in FIG. 5 and FIGS. 6A and 6B, the connection member 10 passes through the space SP1 formed in the block conductor 2, so that the first electrode 1F And the other main surface of the block conductor 2 can be enlarged. Further, since the volume of the space SP1 occupying the block conductor 2 is small, the thermal resistance of the block conductor 2 is further reduced. Therefore, the heat generated in the power semiconductor element 1 can be dissipated more efficiently.

  The space SP1 is formed so as to be exposed to the side surface of the block conductor 2 facing the side where the third conductor 9 exists, the side surface connected to one side thereof, and the other main surface. May be.

-Fourth Embodiment of Semiconductor Module-
A power semiconductor module 100C, which is a fourth embodiment of the semiconductor module according to the present invention, will be described with reference to FIGS.

  FIG. 7 is a cross-sectional view of the power semiconductor module 100 </ b> C taken along an arrowed line including a line A <b> 12-A <b> 12 illustrated in FIG. 8. FIG. 8A is a cross-sectional view of the power semiconductor module 100C as viewed in the direction of the section including the line A10-A10 shown in FIG. FIG. 8B is a cross-sectional view of the power semiconductor module 100C taken along the line A11-A11 shown in FIG.

  Similarly to the power semiconductor modules 100A and 100B, the power semiconductor module 100C is different from the power semiconductor module 100 according to the first embodiment in the formation position of the space SP1. Since other than that is common with the power semiconductor module 100, description of a common location is abbreviate | omitted.

  As shown in FIGS. 7 and 8A and 8B, the space SP1 includes a side surface facing the side where the third conductor 9 of the block conductor 2 exists, and a side surface connected to both sides thereof. Further, it may be a triangular triangular cutout portion formed so as to be exposed to the other main surface.

  Even in this case, as shown in FIG. 8A, the maximum cross-sectional area of the block conductor 2 represented by the area of the hatched portion (rectangle) is the power semiconductor element 1 represented by the area of the region within the outer dotted line. It is larger than the area of one main surface.

  In the power semiconductor module 100C, as shown in FIGS. 7 and 8A and 8B, the volume of the space SP1 in the block conductor 2 is small, so that the thermal resistance of the block conductor 2 is further reduced. Therefore, the heat generated in the power semiconductor element 1 can be dissipated more efficiently.

-Fifth Embodiment of Semiconductor Module-
A power semiconductor module 100D which is a fifth embodiment of the semiconductor module according to the present invention will be described with reference to FIGS.

  FIG. 9 is a cross-sectional view corresponding to the cross-sectional view of FIG. 1 for explaining the possibility that the second bonding material S2 and the third bonding material S3 come into contact with each other and short-circuit in the power semiconductor module. is there.

  In the power semiconductor module 100D, the third bonding material S3 is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, A difference from the power semiconductor module 100 according to the first embodiment is that an annular recess T1 is formed on the surface joined to the power semiconductor element 1. Since other than that is common with the power semiconductor module 100, description of a common location is abbreviate | omitted.

  When the third bonding material S3 is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, the formation of the third bonding material S3 is the third This is performed by sintering in a state where the metal nano-particle paste is interposed between the electrode 1T and the second conductor 6. That is, the third bonding material S3 is not melted in the formation process and becomes liquid.

  In the case where the third bonding material S3 is melted in the formation process such as solder and becomes liquid, even if the adhesion amount to the side surface of the power semiconductor element 1 is increased before being melted by heating, the power Since the material of the semiconductor element 1 is silicon or silicon carbide, the wettability with respect to the liquid solder is low. Accordingly, the liquid solder flows toward the second conductor 6 and solidifies into the third bonding material S3, so that the insulation between the first electrode 1F and the third electrode 1T becomes a problem. It does not remain on the side surface of the power semiconductor element 1.

  On the other hand, when the third bonding material S3 is made of a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, for example, a nanoparticle paste of these metals When the supply amount is large and the adhesion amount to the side surface of the power semiconductor element 1 is large, it does not melt and flow down like solder, and remains attached. Therefore, the first electrode and the third electrode of the power semiconductor element 1 are in electrical proximity, and as shown in FIG. There is a possibility that it cannot be secured.

  Therefore, when the third bonding material S3 is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, it is possible to maintain insulation. preferable. FIG. 10A is a cross-sectional view corresponding to the cross-sectional view of FIG. 1 of the power semiconductor module 100D in which such insulation is maintained. FIG. 10B is a schematic diagram for explaining the positional relationship between the outer peripheral edge of the power semiconductor element 1 and the annular recess T1 included in the second conductor 6 in the power semiconductor module 100D.

  As shown in FIGS. 10A and 10B, the second conductor 6 includes an annular recess T <b> 1 on the surface joined to the power semiconductor element 1. And when the cyclic | annular recessed part T1 and the power semiconductor element 1 with which the 2nd conductor 6 is provided are seen from the thickness direction of a block conductor, the outer periphery (FIG.10 (B)) of the other main surface of the power semiconductor element 1 (Shown by a dotted line in FIG. 2) is located between the inner peripheral edge and the outer peripheral edge of the annular recess provided in the second conductor.

  In the power semiconductor module 100D, an excess of the metal nanoparticle paste moves to the annular recess T1 provided in the second conductor 6, so that the first electrode 1F of the power semiconductor element 1 and the first paste Therefore, it is possible to reliably avoid the electrical proximity or short circuit between the third electrode 1T and the high insulation.

-Sixth embodiment of a semiconductor module-
A power semiconductor module 100E which is a sixth embodiment of the semiconductor module according to the present invention will be described with reference to FIG.

  FIG. 11A is a cross-sectional view corresponding to the cross-sectional view of FIG. 1 of the power semiconductor module 100E in which such insulation is maintained. FIG. 11B is a schematic diagram for explaining the positional relationship between the outer peripheral edge of the power semiconductor element 1 and the convex portion T2 provided in the block conductor 2 in the power semiconductor module 100E.

  In the power semiconductor module 100E, the second bonding material S2 is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, and the block conductor 2 is the other main component. It differs from the power semiconductor module 100 which is 1st Embodiment that the convex part is provided in the surface side. Since other than that is common with the power semiconductor module 100, description of a common location is abbreviate | omitted.

  As shown in FIGS. 11A and 11B, the block conductor 2 has a convex portion on the other main surface side. When the block conductor 2 and the power semiconductor element 1 are viewed from the thickness direction of the block conductor 2, the outer peripheral edge of the one main surface of the power semiconductor element 1 is the outer peripheral edge of the convex portion T2 provided in the block conductor 2 When the block conductor 2 is not provided with the above-described space SP, that is, when the block conductor 2 is assumed to be a simple rectangular parallelepiped, the block conductor 2 is positioned between the outer peripheral edge of the other main surface of the block conductor 2.

  Even when the second bonding material S2 is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, the same as described in the fifth embodiment There are concerns. On the other hand, in the power semiconductor module 100E, among the metal nanoparticle pastes described above, excess moves to the side surface (stepped portion) of the convex portion T2, so that the first electrode and the third electrode of the power semiconductor element Are reliably prevented from being electrically close to each other or short-circuited, and high insulation can be reliably maintained.

-Seventh embodiment of a semiconductor module-
A power semiconductor module 100F, which is a seventh embodiment of the semiconductor module according to the present invention, will be described with reference to FIG. 12 is a cross-sectional view of the power semiconductor module 100F corresponding to the cross-sectional view of FIG.

  In the power semiconductor module 100F, the second bonding material S2 and the third bonding material S3 are sintered bodies of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them. The second conductor 6 having an annular recess T1 on the surface bonded to the power semiconductor element 1 described in the fifth embodiment, and the convex portion on the other main surface side described in the sixth embodiment. The power semiconductor module includes the block conductor 2 provided as a constituent element.

  In the power semiconductor module 100F, of the metal nano-particle paste that becomes the second bonding material S2, the extra one moves to the side surface of the convex portion T2. In addition, of the metal nanoparticle paste that is to be the third bonding material S3, an excessive amount moves to the annular recess T1 provided in the second conductor 6. That is, by both effects, the first electrode 1F and the third electrode 1T of the power semiconductor element 1 can be more reliably avoided from being in electrical proximity, and high insulation can be more reliably maintained. .

-Eighth Embodiment of Semiconductor Module-
A power semiconductor module 100G which is an eighth embodiment of the semiconductor module according to the present invention will be described with reference to FIG. FIG. 13 is a cross-sectional view of the power semiconductor module 100G corresponding to the cross-sectional view of FIG.

  The power semiconductor module 100G is different from the power semiconductor module 100B according to the third embodiment in the form of the connection member 10 and the volume of the space SP. Since other than that is common with the power semiconductor module 100B, description of a common location is abbreviate | omitted.

  As shown in FIG. 13, a clip (plate member) may be used as the connection member 10 instead of a wire. The material of the clip is preferably copper or a copper alloy. When the connection member 10 is a clip, for example, the position does not change even when an impact is applied. Further, since the metal plate is formed by bending, the height can be reduced. As a result, the volume of the space SP1 can be reduced.

  Therefore, the junction area between the first electrode 1F and the other main surface of the block conductor 2 can be increased. Further, since the volume of the space SP1 occupying the block conductor 2 is small, the thermal resistance of the block conductor 2 is further reduced. Therefore, the heat generated in the power semiconductor element 1 can be dissipated more efficiently.

-Ninth embodiment of a semiconductor module-
A power semiconductor module 100H, which is a ninth embodiment of the semiconductor module according to the present invention, will be described with reference to FIG. 14 is a cross-sectional view of the power semiconductor module 100H corresponding to the cross-sectional view of FIG.

  As described above, the power semiconductor module is used for an inverter for driving an electrical equipment such as a power steering of an automobile. In recent years, as electric vehicles have become more and more electronic, various electric devices have been installed, and restrictions on installation space have become severe. Furthermore, there are cases where installation of a plurality of power semiconductor modules is required in order to improve safety and reliability by using electrical equipment as a redundant system. Therefore, there is a strong demand for downsizing of the power semiconductor module.

  At that time, in order to reduce the size of the power semiconductor module, that is, to reduce the mounting area, it is preferable to arrange a plurality of paths and components in a multi-stage arrangement instead of arranging them in a plane. That is, the power semiconductor module 100H has a multi-stage arrangement in accordance with the above purpose in order to make the power semiconductor module 100 which is the first embodiment of the semiconductor module according to the present invention a redundant system.

  The power semiconductor module 100H includes another power semiconductor element 11 and another block conductor 12 between the second conductor 6 and the third conductor 9 and the second insulating layer 7 in the power semiconductor module 100. The fourth conductor 16, the fifth conductor 19, and another connection member 20 are inserted. As described above, the description of the parts common to the power semiconductor module 100 is omitted.

  Like the power semiconductor element 1, the power semiconductor element 11 includes the first electrode 11F and the second electrode 11S on one main surface, and the third electrode 11T on the other main surface. Further, similarly to the power semiconductor element 1, a power MOSFET, an IGBT, or the like can be used.

  When the direction perpendicular to the one main surface of the block conductor 12 is the thickness direction of the block conductor 12, the maximum cross-sectional area of the block conductor 12 in the thickness direction is larger than the area of the one main surface of the power semiconductor element 11. Further, like the block conductor 2, the block conductor 12 includes a space SP2 formed so as to be in non-contact with the second electrode 11S and the connection member 20.

  In this embodiment, the space SP2 is formed so as to be exposed on the side surface of the block conductor 12 facing the side where the sixth conductor 19 is present, and the one main surface and the other main surface, like the space SP1. It is the groove-shaped recessed part made. Further, the block conductor 12 is a rectangular parallelepiped when the recess is excluded as described above, and the maximum cross-sectional area of the block conductor 12 is equal to the areas of the one main surface and the other main surface, and the power semiconductor element 11 On the other hand, it is larger than the area of the main surface.

  In addition, the 4th conductor 16, the 5th conductor 19, and the connection member 20 can also be based on the 2nd conductor 6, the 3rd conductor 9, and the connection member 10, respectively. On the other hand, the power semiconductor module 100H can be appropriately changed depending on the design.

  The second conductor 6 and one main surface of the block conductor 12 are joined by a fourth joining material S4, and both are electrically and thermally connected. The first electrode 11F and the other main surface of the block conductor 12 are joined by a fifth joining material S5, and are similarly electrically and thermally connected. The third electrode 11T and the fourth conductor 16 are joined by a sixth joining material S6 and are similarly electrically and thermally connected. As the fourth bonding material S4, the fifth bonding material S5, and the sixth bonding material S6, those according to the first bonding material S1, the second bonding material S2, and the third bonding material S3, respectively. It can be.

  In the power semiconductor module 100H, as shown in FIG. 14, the connection member 10 passes through the space SP1 formed in the block conductor 2, and the connection member 20 passes through the space SP2 formed in the block conductor 12. . Therefore, the bonding area between the first electrode 1F of the power semiconductor element 1 and the other main surface of the block conductor 2, and the bonding area between the first electrode 11F of the power semiconductor element 11 and the other main surface of the block conductor 12, Each can be enlarged.

  Since the maximum cross-sectional area of the block conductor 2 in the thickness direction is larger than the area of the one main surface of the power semiconductor element 1, and the maximum cross-sectional area of the block conductor 12 is larger than the area of the one main surface of the power semiconductor element 11, the block conductor 2 and the thermal resistance in the block conductor 12 are reduced. As a result, the amount of heat dissipated from the upper surface of the power semiconductor element 1 and the amount of heat dissipated through the third conductor 6 can be increased. Therefore, the heat generated in the power semiconductor element 1 and the power semiconductor element 11 can be efficiently dissipated.

  In addition, this invention is not limited to said embodiment, A various application and deformation | transformation can be added within the scope of this invention. In addition, it is pointed out that each embodiment described in this specification is an exemplification, and a partial replacement or combination of configurations is possible between different embodiments.

100, 100A, 100B, 100C, 100D, 100E, 100F, 100G, 100H Power semiconductor module 1, 11 Power semiconductor element 1F First electrode 1S Second electrode 1T Third electrode 2, 12 Block conductor 3 First Conductor 6 Second conductor 9 Third conductor 16 Fourth conductor 19 Fifth conductor 10, 20 Connecting member S1 First bonding material S2 Second bonding material S3 Third bonding material S4 Fourth bonding material S5 Fifth bonding material S6 Sixth bonding material SP1, SP2 Space

Claims (5)

A semiconductor element including a first electrode and a second electrode on one main surface and a third electrode on the other main surface; one main surface and the other main surface; the one main surface and the other main surface; A semiconductor module comprising a block conductor having a side surface connecting the first conductor, a first conductor, a second conductor, a third conductor, and a connecting member;
The first conductor and one main surface of the block conductor, the first electrode and the other main surface of the block conductor, and the third electrode and the second conductor are bonded by a bonding material. The second electrode and the third conductor are connected via the connection member,
When the direction perpendicular to the one main surface of the block conductor is the thickness direction of the block conductor, the maximum cross-sectional area of the block conductor in the thickness direction is larger than the area of the one main surface of the semiconductor element,
The block conductor includes a space formed so as to be non-contact with the second electrode and the connection member ,
The semiconductor module according to claim 1, wherein the space is a recess formed so as to be exposed to at least one of side surfaces of the block conductor and one main surface and the other main surface of the block conductor . The first conductor and one main surface of the block conductor are bonded by a first bonding material, the first electrode and the other main surface of the block conductor are bonded by a second bonding material, 3 electrodes and the second conductor are joined by a third joining material,
At least one of the first bonding material and the second bonding material is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them, the third bonding material, characterized silver, copper, gold, or a sintered body of at least two metal alloy nanoparticles are selected from among those, or that solidified it is a solder, according to claim 1 the semiconductor module according to. The third bonding material is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them,
The second conductor includes an annular recess on a surface bonded to the semiconductor element,
When the annular recess provided in the second conductor and the semiconductor element are viewed from the thickness direction of the block conductor, the outer periphery of the other main surface of the semiconductor element is provided in the second conductor. The semiconductor module according to claim 2 , wherein the semiconductor module is located between an inner peripheral edge and an outer peripheral edge of the annular recess. The second bonding material is a sintered body of nanoparticles of silver, copper, gold, or an alloy of at least two kinds of metals selected from them,
The block conductor includes a convex portion on the other main surface side,
When the block conductor and the semiconductor element are viewed from the thickness direction of the block conductor, the outer peripheral edge of the one main surface of the semiconductor element is the outer peripheral edge of the end of the convex portion provided in the block conductor; characterized in that located between the outer peripheral edge of the other major surface of the block conductors assuming that no said space is provided in the block conductor, semiconductor module according to claim 2 or 3 . Said block conductor is characterized in that it comprises a parallel one main surface and the other main surface to each other, the semiconductor module according to any one of claims 1 to 4.