Semiconductor device

Abstract

To provide a semiconductor device capable of suppressing temperature fluctuation in a semiconductor element.SOLUTION: The semiconductor device includes a semiconductor element 30 having a first electrode 31, a wire 41 electrically connected to the first electrode 31, and a sealing resin 50 covering the semiconductor element 30 and the wire 41, and further includes a heat storage member 60 interposed between the first electrode 31 and the sealing resin 50 and having a thermal conductivity higher than that of the sealing resin 50.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present disclosure relates to semiconductor devices. [Background technology]

[0002] Patent Document 1 discloses an example of a semiconductor device including a semiconductor element, a wire, and a sealing resin. The semiconductor element has a source electrode. The wire is connected to the source electrode. The sealing resin covers the source electrode and the wire. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-174951 Summary of the Invention [Problem to be solved by the invention]

[0004] When a semiconductor element is repeatedly energized, the semiconductor element repeatedly generates heat, and when the temperature fluctuations in the semiconductor element become large, the state of connection of the wires, for example, can become unstable.

[0005] The present disclosure has been made in light of the above circumstances, and an object of the present disclosure is to provide a semiconductor device that is capable of suppressing temperature fluctuations in semiconductor elements. [Means for solving the problem]

[0006] The semiconductor device of the present disclosure comprises a semiconductor element having a first electrode, a wire connected to the first electrode, and a sealing resin covering the semiconductor element and the wire, and further comprises a heat storage member interposed between the first electrode and the sealing resin and having a higher thermal conductivity than the sealing resin. [Effects of the Invention]

[0007] According to the present disclosure, temperature fluctuations in semiconductor elements can be suppressed.

[0008] Other features and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view showing a semiconductor device according to a first embodiment of the present disclosure. [Figure 2] FIG. 2 is a partial perspective view showing the semiconductor device according to the first embodiment of the present disclosure. [Figure 3] FIG. 3 is a plan view showing the semiconductor device according to the first embodiment of the present disclosure. [Figure 4] FIG. 4 is a partial plan view showing the semiconductor device according to the first embodiment of the present disclosure. [Figure 5] FIG. 5 is a bottom view showing the semiconductor device according to the first embodiment of the present disclosure. [Figure 6] FIG. 6 is a side view showing the semiconductor device according to the first embodiment of the present disclosure. [Figure 7] FIG. 7 is a front view showing the semiconductor device according to the first embodiment of the present disclosure. [Figure 8] FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. [Figure 9] FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. [Figure 10] FIG. 10 is a cross-sectional view taken along line XX in FIG. [Figure 11] FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. [Figure 12] FIG. 12 is a partially enlarged plan view showing the semiconductor device according to the first embodiment of the present disclosure. [Figure 13] 13 is a partially enlarged cross-sectional view taken along line XIII-XIII in FIG. [Figure 14] FIG. 14 is a partial plan view showing a first modified example of the semiconductor device according to the first embodiment of the present disclosure. [Figure 15] FIG. 15 is a cross-sectional view showing a second modification of the semiconductor device according to the first embodiment of the present disclosure. [Figure 16] FIG. 16 is a partially enlarged plan view showing a third modified example of the semiconductor device according to the first embodiment of the present disclosure. [Figure 17] FIG. 17 is a partial enlarged plan view showing a fourth modified example of the semiconductor device according to the first embodiment of the present disclosure. [Figure 18] 18 is a partially enlarged cross-sectional view taken along line XVIII-XVIII in FIG. [Figure 19] FIG. 19 is a partially enlarged plan view showing a semiconductor device according to the second embodiment of the present disclosure. [Figure 20] FIG. 20 is a partially enlarged cross-sectional view taken along the line XX-XX in FIG. [Figure 21] FIG. 21 is a partially enlarged plan view showing a semiconductor device according to a third embodiment of the present disclosure. [Figure 22] 22 is a partially enlarged cross-sectional view taken along line XXII-XXII in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0010] Preferred embodiments of the present disclosure will now be described in detail with reference to the drawings.

[0011] The terms "first," "second," "third," etc. in this disclosure are used for identification purposes only and are not intended to impose any ranking on their objects.

[0012] In this disclosure, unless otherwise specified, the terms "a certain object A is formed on an object B" and "a certain object A is formed on an object B" include "a certain object A is formed directly on an object B" and "a certain object A is formed on an object B with another object interposed between the objects A and B." Similarly, the terms "a certain object A is disposed on an object B" and "a certain object A is disposed on an object B" include "a certain object A is disposed directly on an object B" and "a certain object A is disposed on an object B with another object interposed between the objects A and B," unless otherwise specified. Similarly, the term "a certain object A is located on an object B" includes "a certain object A is located on an object B in contact with the object B" and "a certain object A is located on an object B with another object interposed between the objects A and B," unless otherwise specified. Furthermore, unless otherwise specified, the phrase "an object A overlaps an object B when viewed in a certain direction" includes "an object A overlaps the entire object B" and "an object A overlaps a part of an object B." Furthermore, in this disclosure, "a surface A faces (one side or the other side of) direction B" is not limited to the case where the angle of surface A with respect to direction B is 90°, but also includes the case where surface A is tilted with respect to direction B.

[0013] First Embodiment 1 to 13 show a semiconductor device according to a first embodiment of the present disclosure. The application of the semiconductor device A10 of this embodiment is not limited in any way, and it may be used in electronic devices equipped with a power conversion circuit, such as a DC-DC converter. The semiconductor device A10 includes a first lead 11, a second lead 12, a third lead 13, a fourth lead 14, a semiconductor element 30, a plurality of wires 41, 42, and 43, a heat storage member 60, and a sealing resin 50.

[0014] FIG. 1 is a perspective view showing the semiconductor device A10. FIG. 2 is a partial perspective view showing the semiconductor device A10. FIG. 3 is a plan view showing the semiconductor device A10. FIG. 4 is a partial plan view showing the semiconductor device A10. FIG. 5 is a bottom view showing the semiconductor device A10. FIG. 6 is a side view showing the semiconductor device A10. FIG. 7 is a front view showing the semiconductor device A10. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 4. FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. 4. FIG. 10 is a cross-sectional view taken along line XX in FIG. 4. FIG. 11 is a cross-sectional view taken along line XI-XI in FIG. 4. FIG. 12 is a partially enlarged plan view showing the semiconductor device A10. FIG. 13 is a partially enlarged cross-sectional view taken along line XIII-XIII in FIG. 12.

[0015] In these figures, the x, y, and z directions are perpendicular to one another. One side of the x direction is the x1 side, the other the x2 side, one side of the y direction is the y1 side, the other the y2 side, and one side of the z direction is the z1 side, the other the z2 side.

[0016] [1st lead 11] 1 to 5 and 7 to 12, the first lead 11 has a die pad portion 111 and a terminal portion 112. The first lead 11 is a conductive member on which the semiconductor element 30 is mounted and which forms part of a conductive path between the semiconductor element 30 and a wiring board (not shown) or the like on which the semiconductor device A10 is mounted.

[0017] The first lead 11 includes, for example, copper (Cu) or a copper alloy. The first lead 11 may also have a surface metal layer (not shown). The surface metal layer includes, for example, Ag (silver), Ni (nickel), or the like.

[0018] The die pad portion 111 has a first main surface 111A, a first back surface 111B, and a through hole 111C. The first main surface 111A faces the z1 side in the z direction. The first back surface 111B faces the z2 side in the z direction. The through hole 111C penetrates the die pad portion 111 in the z direction. The shape of the through hole 111C is not limited in any way, and in the illustrated example, it is circular when viewed along the z direction.

[0019] The terminal portion 112 is connected to the die pad portion 111 and includes a portion extending to the x2 side in the x direction. The die pad portion 111 and the terminal portion 112 are electrically connected to each other. A portion of the terminal portion 112 is covered with the sealing resin 50. The portion of the terminal portion 112 covered with the sealing resin 50 is bent when viewed along the y direction. The surface of the portion of the terminal portion 112 exposed from the sealing resin 50 may be plated with, for example, tin (Sn).

[0020] [Second Lead 12] As shown in FIGS. 1 to 5, 7, and 9, the second lead 12 is spaced apart from the first lead 11 and is located on the y1 side of the first lead 11 in the y direction. The first lead 11 is electrically connected to the semiconductor element 30 via a wire 41. The second lead 12 has a wire pad portion 121 and a terminal portion 122. The wire pad portion 121 is covered with a sealing resin 50. The wire pad portion 121 may be plated with, for example, silver (Ag) or tin (Sn). The terminal portion 122 is connected to the wire pad portion 121. A portion of the terminal portion 122 is covered with the sealing resin 50, and another portion is exposed from the sealing resin 50. The terminal portion 122 extends in the x direction, for example, parallel to the terminal portion 112. The surface of the terminal portion 122 may be plated with, for example, tin (Sn).

[0021] [3rd lead 13] As shown in FIGS. 1 to 5, 7, and 10, the third lead 13 is spaced apart from the first lead 11 and the second lead 12 and is located on the y1 side of the second lead 12 in the y direction. The third lead 13 is electrically connected to the semiconductor element 30 via a wire 42. The third lead 13 has a wire pad portion 131 and a terminal portion 132. The wire pad portion 131 is covered with a sealing resin 50. The wire pad portion 131 may be plated with, for example, silver (Ag) or tin (Sn). The terminal portion 132 is connected to the wire pad portion 131. A portion of the terminal portion 132 is covered with the sealing resin 50, and another portion is exposed from the sealing resin 50. The terminal portion 132 extends in the x direction, for example, parallel to the terminal portions 112 and 122. The surface of the terminal portion 132 may be plated with, for example, tin (Sn).

[0022] [4th lead 14] As shown in FIGS. 1 to 5, 7, and 11, the fourth lead 14 is spaced apart from the first lead 11, the second lead 12, and the third lead 13 and is located on the y1 side of the third lead 13 in the y direction. The fourth lead 14 is electrically connected to the semiconductor element 30 via a wire 43. The fourth lead 14 has a wire pad portion 141 and a terminal portion 142. The wire pad portion 141 is covered with a sealing resin 50. The wire pad portion 141 may be plated with, for example, silver (Ag) or tin (Sn). The terminal portion 142 is connected to the wire pad portion 141. A portion of the terminal portion 142 is covered with the sealing resin 50, and another portion is exposed from the sealing resin 50. The terminal portion 142 extends in the x direction, for example, parallel to the terminal portions 112, 122, and 132. The surface of the terminal portion 142 may be plated with, for example, tin (Sn).

[0023] [Semiconductor element 30] As shown in FIGS. 2, 4, and 9 to 13, the semiconductor element 30 is mounted on the first main surface 111A of the die pad portion 111. In the semiconductor device A10, the specific configuration of the semiconductor element 30 is not limited in any way. In this embodiment, the semiconductor element 30 is a switching element, for example, an n-channel, vertical-structure metal-oxide-semiconductor field-effect transistor (MOSFET). The semiconductor element 30 is not limited to a MOSFET. The semiconductor element 30 may be another transistor, such as an insulated gate bipolar transistor (IGBT). Furthermore, the semiconductor element 30 may be an LSI (large-scale integration) or a diode. The semiconductor element 30 has a semiconductor layer 35, a first electrode 31, a second electrode 32, a third electrode 33, and a fourth electrode 34. The thickness of the semiconductor element 30 in the z direction is, for example, 100 μm or more and 1000 μm or less.

[0024] The semiconductor layer 35 includes a compound semiconductor substrate. The main material of the compound semiconductor substrate is silicon carbide (SiC). Alternatively, silicon (Si) may be used as the main material of the compound semiconductor substrate.

[0025] The first electrode 31 is disposed on the z1 side of the semiconductor layer 35 in the z direction. A current corresponding to the power converted by the semiconductor element 30 flows through the first electrode 31. In this embodiment, the first electrode 31 is a source electrode.

[0026] The second electrode 32 is disposed on a portion of the semiconductor layer 35 on the z1 side in the z direction. The second electrode 32 is located away from the first electrode 31. A voltage for driving the semiconductor element 30 is applied to the second electrode 32. In this embodiment, the third electrode 33 is a gate electrode. When viewed along the z direction, the area of ​​the second electrode 32 is smaller than the area of ​​the first electrode 31.

[0027] The third electrode 33 is disposed on a portion of the semiconductor layer 35 on the z1 side in the z direction. The third electrode 33 is located away from the first electrode 31 and the second electrode 32. In this embodiment, the third electrode 33 is electrically connected to the first electrode 31 and is a so-called source sense electrode. When viewed along the z direction, the area of ​​the third electrode 33 is smaller than the area of ​​the first electrode 31.

[0028] The fourth electrode 34 is disposed on a portion of the semiconductor layer 35 on the z2 side in the z direction. The fourth electrode 34 faces the first main surface 111A of the die pad portion 111 of the first lead 11. A current corresponding to the power before being converted by the semiconductor element 30 flows through the second electrode 32. In this embodiment, the second electrode 32 is a drain electrode. The fourth electrode 34 is conductively joined to the first main surface 111A via a joining layer 39. The joining layer 39 is, for example, solder, Ag (silver) paste, or the like.

[0029] The first lead 11 is electrically connected to the fourth electrode 34 of the semiconductor element 30. Therefore, the terminal 112 is the drain terminal of the semiconductor device A10. The second lead 12 is electrically connected to the first electrode 31 of the semiconductor element 30. Therefore, the terminal 122 is the source terminal of the semiconductor device A10. The third lead 13 is electrically connected to the second electrode 32 of the semiconductor element 30. Therefore, the terminal 132 is the gate terminal of the semiconductor device A10. The fourth lead 14 is electrically connected to the third electrode 33 of the semiconductor element 30. Therefore, the terminal 142 is the source sense terminal of the semiconductor device A10. In the illustrated example, the distance in the y direction between the terminals 112 and 122 is greater than both the distance in the y direction between the terminals 122 and 132 and the distance in the y direction between the terminals 132 and 142.

[0030] [Heat storage member 60] The heat storage member 60 is interposed between the first electrode 31 of the semiconductor element 30 and the sealing resin 50. The heat storage member 60 has a higher thermal conductivity than the sealing resin 50. The heat storage member 60 is bonded to the first electrode 31. In this embodiment, the heat storage member 60 is conductively bonded to the first electrode 31 via a bonding layer 69. The bonding layer 69 is, for example, solder, Ag (silver) paste, or the like. The heat storage member 60 may also be bonded directly to the first electrode 31 without the bonding layer 69. In this case, the heat storage member 60 is bonded to the first electrode 31 by, for example, solid-state diffusion bonding, ultrasonic bonding, or the like.

[0031] There are no particular limitations on the material of the heat storage member 60, and in this embodiment, the material is conductive. The material of the heat storage member 60 is preferably a metal, and examples include Cu (copper) and Al (aluminum).

[0032] The shape of the heat storage member 60 is not limited in any way and may be various shapes such as a rectangle, a triangle, a polygon, a circle, or an ellipse when viewed from the z direction. In the example shown, the heat storage member 60 is rectangular when viewed from the z direction. Furthermore, the size of the heat storage member 60 is not limited in any way. In the example shown, an edge 61 of the heat storage member 60 coincides with an edge of the first electrode 31 when viewed from the z direction. Alternatively, the heat storage member 60 may have a shape and size that allows it to be contained within the first electrode 31 when viewed from the z direction.

[0033] The thickness of the heat storage member 60 in the z direction is not particularly limited and is, for example, 100 μm or more and 2000 μm or less. Furthermore, the thickness of the heat storage member 60 in the z direction is preferably 1 time or more and 2 times or less the thickness of the semiconductor element 30 in the z direction.

[0034] [Wire 41] As shown in FIGS. 2, 4, 9, 12, and 13, the plurality of conductive members 40 are electrically connected to the first electrodes 31 of the semiconductor element 30 and are connected to the wire pad portions 121 of the second leads 12. The specific configuration of the wires 41 is not limited in any way and includes configurations in which the cross-sectional shape is circular, elliptical, flattened rectangular, etc. In the illustrated example, the wires 41 have a circular cross-sectional shape. The wires 41 are connected by wedge bonding, for example. The material of the wires 41 is not limited in any way and includes, for example, Cu (copper), Al (aluminum), etc. In this embodiment, two wires 41 are individually connected to the first electrodes 31 and the wire pad portions 121.

[0035] In this embodiment, the wire 41 is connected to the heat storage member 60 and is electrically connected to the first electrode 31 via the heat storage member 60. In other words, the heat storage member 60 is interposed between the first electrode 31 and the wire 41.

[0036] [Wire 42] As shown in Figures 2, 4, 10, and 12, the wire 42 is connected to the second electrode 32 of the semiconductor element 30 and the wire pad portion 131 of the third lead 13. The specific configuration of the wire 42 is not limited in any way, and includes configurations in which the cross-sectional shape is circular, elliptical, flattened rectangular, etc. The wire 42 is connected by wedge bonding, for example. The cross-sectional size of the wire 42 is smaller than the cross-sectional size of the wire 41. The material of the wire 42 is not limited in any way, and includes, for example, Cu (copper), Al (aluminum), etc.

[0037] [Wire 43] As shown in Figures 2, 4, 11 and 12, the wire 43 is connected to the third electrode 33 of the semiconductor element 30 and the wire pad portion 141 of the fourth lead 14. The specific configuration of the wire 43 is not limited in any way, and includes configurations in which the cross-sectional shape is circular, elliptical, flattened rectangular, etc. The wire 43 is connected by wedge bonding, for example. The cross-sectional size of the wire 43 is smaller than the cross-sectional size of the wire 41. The material of the wire 43 is not limited in any way, and includes, for example, Cu (copper), Al (aluminum), etc.

[0038] [Sealing resin 50] As shown in FIGS. 1 to 11 , the sealing resin 50 covers the semiconductor element 30, the plurality of wires 41, 42, and 43, the heat storage member 60, and portions of the first lead 11, the second lead 12, the third lead 13, and the fourth lead 14. The sealing resin 50 has electrical insulation properties. The sealing resin 50 is made of a material containing, for example, black epoxy resin. The sealing resin 50 has a resin main surface 51, a resin back surface 52, a pair of first side surfaces 53, a pair of second side surfaces 54, a pair of openings 55, a mounting hole 56, and a recess 57.

[0039] The resin main surface 51 faces the z1 side in the z direction. The resin back surface 52 faces the z2 side in the z direction. A first back surface 111B of the die pad portion 111 is exposed from the resin back surface 52. The first back surface 111B and the resin back surface 52 are flush with each other.

[0040] The pair of first side surfaces 53 are spaced apart from each other in the x direction. The pair of first side surfaces 53 are connected to the resin main surface 51 and the resin back surface 52. A terminal portion 112 of the first lead 11, a terminal portion 122 of the second lead 12, a terminal portion 132 of the third lead 13, and a terminal portion 142 of the fourth lead 14 protrude from the first side surface 53 facing the x2 side in the x direction.

[0041] The pair of second side surfaces 54 are spaced apart from each other in the y direction and are connected to the resin main surface 51 and the resin rear surface 52.

[0042] The pair of openings 55 are positioned apart from each other in the y direction. Each of the pair of openings 55 is recessed inward into the sealing resin 50 from the resin main surface 51 and one of the pair of second side surfaces 54. A part of the first main surface 111A of the die pad portion 111 of the first lead 11 is exposed from the pair of openings 55.

[0043] The mounting hole 56 penetrates the sealing resin 50 in the z direction from the resin main surface 51 to the resin back surface 52. When viewed from the z direction, the mounting hole 56 is contained within the through hole 111C of the die pad portion 111 of the first lead 11. The inner peripheral surface of the die pad portion 111 that defines the through hole 111C is covered with the sealing resin 50. As a result, when viewed along the z direction, the maximum dimension of the mounting hole 56 is smaller than the dimension of the through hole 111C.

[0044] The recess 57 is located in the y direction between the terminal portion 112 and the terminal portion 122. The recess 57 is recessed from the first side surface 53 located on the x2 side in the x direction to the x1 side in the x direction.

[0045] Next, the operation of the semiconductor device A10 will be described.

[0046] A heat storage member 60 is interposed between the first electrode 31 and the sealing resin 50. The heat storage member 60 has a higher thermal conductivity than the sealing resin 50. Therefore, heat generated when current is applied to the semiconductor element 30 during operation of the semiconductor device A10 is transferred to the heat storage member 60 and stored in the heat storage member 60. This makes it possible to suppress temperature fluctuations in the semiconductor element 30. This makes it possible to avoid, for example, the connection state of the wire 41 becoming unstable.

[0047] In this embodiment, the heat storage member 60 is interposed between the first electrode 31 and the wire 41. This makes it possible to suppress temperature fluctuations at the connection portion of the wire 41.

[0048] The heat storage member 60 contains a metal such as Cu (copper) or Al (aluminum), which allows heat from the first electrode 31 to be quickly transferred to the heat storage member 60. This is therefore preferable for suppressing temperature fluctuations in the semiconductor element 30.

[0049] The thickness in the z direction of the heat storage member 60 is equal to or greater than one time and equal to or less than two times the thickness in the z direction of the semiconductor element 30. This makes it possible to suppress temperature fluctuations in the semiconductor element 30 while preventing the resistance value between the first electrode 31 and the wire 41 from becoming excessively large.

[0050] In the illustrated example, the heat storage member 60 has a size and shape that match those of the first electrode 31 when viewed from the z direction. This allows heat to be transferred from the entire surface of the first electrode 31 to the heat storage member 60.

[0051] 14 to 22 show modified examples and other embodiments of the present disclosure. In these figures, elements that are the same as or similar to those in the above-described embodiment are given the same reference numerals. Furthermore, the configurations of the various parts in each modified example and each embodiment can be appropriately combined with each other as long as no technical contradiction occurs.

[0052] <First Modification of First Embodiment> 14 shows a first modified example of the semiconductor device A10. In the semiconductor device A11 of this modified example, the configuration of the wires 41 is different from that of the wires 41 of the semiconductor device A10.

[0053] In this modification, the wire 41 has a flat rectangular cross-sectional shape. Such a wire 41 is sometimes called a ribbon. In addition, in this modification, the number of wires 41 is one. This modification also makes it possible to suppress temperature fluctuations in the semiconductor element 30. Furthermore, as can be understood from this modification, the specific configuration of the wire 41 is not limited in any way.

[0054] <Second Modification of First Embodiment> 15 shows a second modified example of the semiconductor device A10. In the semiconductor device A12 of this modified example, the first back surface 111B of the die pad portion 111 is covered with the sealing resin 50. In other words, the first back surface 111B is not exposed from the sealing resin 50.

[0055] This modification also makes it possible to suppress temperature fluctuations in the semiconductor element 30. Furthermore, as can be seen from this modification, the relationship between the die pad portion 111 and the sealing resin 50 is not limited in any way.

[0056] <Third Modification of First Embodiment> 16 shows a third modified example of the semiconductor device A 10. The semiconductor device A13 of this modified example differs from the above-described examples in the configuration of the heat storage member 60.

[0057] In this modification, the edge 61 of the heat storage member 60 has an uneven shape when viewed from the z direction. For example, in the illustrated example, the edge 61 is made up of a plurality of curves, such as sine curves.

[0058] This modification also makes it possible to suppress temperature fluctuations in the semiconductor element 30. Furthermore, as can be seen from this modification, there is no limitation on the shape of the heat storage member 60. By making the edge 61 uneven, the bonding strength between the first electrode 31 and the heat storage member 60 can be increased.

[0059] <Fourth Modification of First Embodiment> 17 and 18 show a fourth modified example of the semiconductor device A 10. The semiconductor device A 14 of this modified example has a different configuration of the heat storage member 60 from the examples described above.

[0060] In this modified example, the heat storage member 60 has a plurality of through holes 62. The through holes 62 penetrate the heat storage member 60 in the z direction. The number and arrangement of the through holes 62 are not limited in any way. In the example shown in the figure, the heat storage member 60 has four through holes 62. The four through holes 62 are arranged corresponding to the four corners of the heat storage member 60. A bonding layer 69 is attached inside the through holes 62.

[0061] This modification also makes it possible to suppress temperature fluctuations in the semiconductor element 30. Furthermore, as can be seen from this modification, there is no limitation on the shape of the heat storage member 60. By attaching the bonding layer 69 to the through hole 62, the bonding strength between the first electrode 31 and the heat storage member 60 can be increased.

[0062] Second Embodiment 19 and 20 show a semiconductor device according to a second embodiment of the present disclosure. A semiconductor device A20 according to this embodiment differs from the above-described embodiments in the configurations of the heat storage member 60 and the wires 41.

[0063] In this embodiment, the heat storage member 60 has an opening 63. The opening 63 penetrates the heat storage member 60 in the z direction, and exposes a part of the first electrode 31 when viewed from the z direction. The wire 41 is connected to the part of the first electrode 31 exposed from the opening 63.

[0064] This embodiment also makes it possible to suppress temperature fluctuations in the semiconductor element 30. Furthermore, as can be understood from this embodiment, the heat storage member 60 is not limited to being interposed between the first electrode 31 and the wire 41.

[0065] <Third embodiment> 21 and 22 show a semiconductor device according to a third embodiment of the present disclosure. A semiconductor device A30 according to this embodiment differs from the above-described embodiments in the configurations of the heat storage member 60 and the wires 41.

[0066] In this embodiment, the wire 41 is connected to the first electrode 31. The heat storage member 60 covers the connection portion between the wire 41 and the first electrode 31. In other words, the heat storage member 60 covers at least a portion of the first electrode 31, a portion of the wire 41, and the boundary portion between the first electrode 31 and the wire 41.

[0067] The heat storage member 60 of this embodiment may be conductive or insulating. Examples of the conductive heat storage member 60 include Ag (silver) paste, sintered Ag (silver), and solder. Examples of the insulating heat storage member 60 include high-thermal-conductivity resins having higher thermal conductivity than the sealing resin 50.

[0068] This embodiment also makes it possible to suppress temperature fluctuations in the semiconductor element 30. Furthermore, this embodiment makes it possible to protect the connection portion between the first electrode 31 and the wire 41 by the heat storage member 60.

[0069] The semiconductor device according to the present disclosure is not limited to the above-described embodiment, and the specific configuration of the semiconductor device according to the present disclosure can be freely modified in various ways.

[0070] [Appendix 1] a semiconductor element having a first electrode; a wire connected to the first electrode; a sealing resin that covers the semiconductor element and the wires, The semiconductor device further comprises a heat storage member interposed between the first electrode and the sealing resin and having a thermal conductivity higher than that of the sealing resin. [Appendix 2] The semiconductor device according to claim 1, further comprising a first lead having a die pad portion on which the semiconductor element is mounted. [Appendix 3] The semiconductor device described in Appendix 2, further comprising a second lead having a wire pad portion to which the wire is connected. [Appendix 4] 4. The semiconductor device according to claim 1, wherein the heat storage member is in contact with the wire. [Appendix 5] 5. The semiconductor device according to claim 4, wherein the heat storage member is interposed between the wire and the first electrode. [Appendix 6] 6. The semiconductor device according to claim 5, wherein the heat storage member is electrically conductive. [Appendix 7] 7. The semiconductor device according to claim 6, wherein the heat storage member contains Cu or Al. [Appendix 8] 8. The semiconductor device of claim 7, wherein the wire comprises Cu or Al. [Appendix 9] 9. The semiconductor device according to any one of claims 5 to 8, wherein the thickness of the heat storage member is at least one time and at most two times the thickness of the semiconductor element. [Appendix 10] 10. The semiconductor device according to claim 1, wherein the heat storage member coincides with the first electrode in a plan view or is included in the first electrode. [Appendix 11] The heat storage member has an opening, 4. The semiconductor device according to claim 1, wherein the wire is connected to a portion of the first electrode that is exposed through the opening. [Appendix 12] 12. The semiconductor device according to any one of claims 1 to 11, further comprising a bonding layer interposed between the heat storage member and the first electrode. [Appendix 13] the wire is bonded to the first electrode; 4. The semiconductor device according to claim 1, wherein the heat storage member covers a joint between the wire and the first electrode. [Appendix 14] 14. The semiconductor device according to claim 13, wherein the heat storage member is electrically conductive. [Appendix 15] 14. The semiconductor device according to claim 13, wherein the heat storage member has insulating properties. [Appendix 16] 16. The semiconductor device according to any one of claims 1 to 15, wherein the semiconductor element is a switching element. [Appendix 17] 17. The semiconductor device according to claim 16, wherein the first electrode is a source electrode. [Explanation of symbols]

[0071] A10, A11, A12, A13, A14, A20, A30: Semiconductor device 11: First lead 12: Second lead 13: Third lead 14: 4th lead 30: Semiconductor element 31: 1st electrode 32: 2nd electrode 33:Third electrode 34: 4th electrode 35: Semiconductor layer 39: Bonding layer 40: Conductive material 41: Wire 42: Wire 43: Wire 50: Sealing resin 51: Resin main surface 52: Resin back 53 :1st side 54:Second side 55 :Aperture 56: Mounting hole 57: Recess 60: Heat storage material 61: Edge 62: Through hole 63: Opening 69: Bonding layer 111: Die pad section 111A: 1st main surface 111B: 1st back side 111C: Through hole 112:Terminal section 121: Wire pad section 122:Terminal section 131: Wire pad section 132:Terminal section 141: Wire pad section 142:Terminal section

Claims

1. a semiconductor element having a first electrode; a wire connected to the first electrode; a sealing resin that covers the semiconductor element and the wires, The semiconductor device further comprises a heat storage member interposed between the first electrode and the sealing resin and having a thermal conductivity higher than that of the sealing resin.

2. The semiconductor device according to claim 1 , further comprising a first lead having a die pad portion on which said semiconductor element is mounted.

3. 3. The semiconductor device according to claim 2, further comprising a second lead having a wire pad portion to which said wire is connected.

4. 4. The semiconductor device according to claim 1, wherein said heat storage member is in contact with said wire.

5. The semiconductor device according to claim 4 , wherein the heat storage member is interposed between the wire and the first electrode.

6. The semiconductor device according to claim 5 , wherein the heat storage member is electrically conductive.

7. The semiconductor device according to claim 6 , wherein said heat storage member contains Cu or Al.

8. The semiconductor device according to claim 7 , wherein the wire contains Cu or Al.

9. 6. The semiconductor device according to claim 5, wherein the thickness of said heat storage member is equal to or greater than one time and equal to or less than two times the thickness of said semiconductor element.

10. The semiconductor device according to claim 1 , wherein the heat storage member coincides with the first electrode in a plan view or is included in the first electrode.

11. The heat storage member has an opening, The semiconductor device according to claim 1 , wherein the wire is connected to a portion of the first electrode that is exposed through the opening.

12. The semiconductor device according to claim 1 , further comprising a bonding layer interposed between said heat storage member and said first electrode.

13. the wire is bonded to the first electrode; 4. The semiconductor device according to claim 1, wherein the heat storage member covers a joint between the wire and the first electrode.

14. The semiconductor device according to claim 13 , wherein the heat storage member is electrically conductive.

15. The semiconductor device according to claim 13 , wherein the heat storage member has insulating properties.

16. The semiconductor device according to claim 1 , wherein the semiconductor element is a switching element.

17. The semiconductor device according to claim 16 , wherein the first electrode is a source electrode.

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