Semiconductor Device

Abstract

To provide a semiconductor device in which the occurrence of a crack in a junction layer can be suppressed while short-circuiting of a plurality of electrodes is prevented, and a manufacturing method for the semiconductor device.SOLUTION: A semiconductor device A10 includes a conductive member 10 including a main surface 101 facing one side of a thickness direction z, a semiconductor element 20 including a plurality of pads 22 opposing the main surface 101, and a plurality of electrodes 31 protruding to the other side of the thickness direction z from the pads 22. The conductive member 10 includes a plurality of concave parts 14 that are depressed to the other side of the thickness direction z from the main surface 101. The semiconductor device A10 additionally includes a junction layer 32 with conductivity that is disposed in the concave parts 14. The electrodes 31 are inserted individually in the concave parts 14. The conductive member 10 and the electrodes 31 are bonded together with the junction layer 32.SELECTED DRAWING: Figure 13

Description

[Technical field]

[0001] The present disclosure relates to a semiconductor element bonded to a conductive member by flip-chip mounting. [Background technology]

[0002] Conventionally, semiconductor devices in which a semiconductor element is bonded to a conductive member (such as a lead frame) by flip mounting are widely known. Patent Document 1 discloses an example of such a semiconductor device. In this semiconductor device, multiple electrodes of a semiconductor element (semiconductor chip in Patent Document 1) are bonded to a conductive member (drawing wiring in Patent Document 1) by a bonding layer (conductor bumps in Patent Document 1). The multiple electrodes of the semiconductor element face the conductive member.

[0003] The bonding layer of the semiconductor device disclosed in Patent Document 1 is made of solder. Therefore, if the number of electrodes is increased in accordance with the circuit configured in the semiconductor element, when the electrodes are bonded to a conductive member via the bonding layer, there is a risk that a short circuit will occur in the electrodes due to the melted bonding layer. Furthermore, the bonding layer is subjected to thermal stress due to the influence of heat generated by the semiconductor element. If the bonding layer is made of solder, cracks are likely to occur due to the thermal stress. Therefore, it is necessary to take measures against these problems. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2018-85522 A Summary of the Invention [Problem to be solved by the invention]

[0005] In view of the above circumstances, an object of the present disclosure is to provide a semiconductor device that can prevent short circuits between multiple electrodes while suppressing the occurrence of cracks in a bonding layer. [Means for solving the problem]

[0006] The semiconductor device provided by the present disclosure comprises a conductive member having a main surface facing one side in a thickness direction, a semiconductor element having a plurality of pads facing the main surface, and a plurality of electrodes protruding from the plurality of pads to the other side in the thickness direction, wherein the conductive member has a plurality of recesses recessed from the main surface to the other side in the thickness direction, and further comprises a bonding layer that is conductive and disposed within the plurality of recesses, wherein the plurality of electrodes are individually inserted into the plurality of recesses, and the conductive member and the plurality of electrodes are bonded by the bonding layer. Effect of the Invention

[0007] According to the semiconductor device and the manufacturing method thereof disclosed herein, it is possible to prevent short circuits between a plurality of electrodes and suppress the occurrence of cracks in the bonding layer.

[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 description of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view of a semiconductor device according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a plan view of the semiconductor device corresponding to FIG. 1, seen through the sealing resin. [Diagram 3] 3 is a plan view of the semiconductor device corresponding to FIG. 2, further showing the semiconductor element, the plurality of electrodes, and the bonding layer. [Figure 4] 2 is a bottom view of the semiconductor device shown in FIG. 1. [Diagram 5] FIG. 2 is a front view of the semiconductor device shown in FIG. [Figure 6] 2 is a rear view of the semiconductor device shown in FIG. [Figure 7] 2 is a right side view of the semiconductor device shown in FIG. [Figure 8] FIG. 2 is a left side view of the semiconductor device shown in FIG. [Figure 9]FIG. 9 is a cross-sectional view taken along line IX-IX in FIG. [Figure 10] FIG. 4 is a cross-sectional view taken along line XX in FIG. [Figure 11] FIG. 4 is a cross-sectional view taken along line XI-XI in FIG. [Figure 12] FIG. 4 is a cross-sectional view taken along line XII-XII in FIG. [Figure 13] FIG. 10 is a partially enlarged view of FIG. [Figure 14] FIG. 10 is a partially enlarged view of FIG. [Figure 15] 2 is a partial enlarged cross-sectional view of a first modified example of the semiconductor device shown in FIG. [Figure 16] 1. FIG. 4 is a partially enlarged cross-sectional view of a second modified example of the semiconductor device shown in FIG. [Figure 17] FIG. 11 is a partially enlarged cross-sectional view of a semiconductor device according to a second embodiment of the present disclosure. [Figure 18] 18 is a partial enlarged cross-sectional view of a modification of the semiconductor device shown in FIG. 17. [Figure 19] FIG. 11 is a partially enlarged cross-sectional view of a semiconductor device according to a third embodiment of the present disclosure. [Figure 20] 20 is a partial enlarged cross-sectional view of a modification of the semiconductor device shown in FIG. 19. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The embodiments for carrying out the present disclosure will be described with reference to the accompanying drawings. Each of the accompanying drawings is drawn in a schematic manner. Each of the accompanying drawings may include omitted and exaggerated parts.

[0011] [First embodiment] A semiconductor device A10 according to a first embodiment of the present disclosure will be described with reference to FIGS. 1 to 14. The semiconductor device A10 includes a conductive member 10, a semiconductor element 20, a plurality of electrodes 31, a bonding layer 32, and a sealing resin 40. As shown in FIG. 1, the package format of the semiconductor device A10 is a QFN (Quad Flat Non-Lead Package). The semiconductor element 20 is a flip-chip type LSI. The semiconductor element 20 includes a switching circuit 212A and a control circuit 212B (each of which will be described in detail later). In the semiconductor device A10, the switching circuit 212A converts DC power (voltage) into AC power (voltage). The semiconductor device A10 is used, for example, as one element constituting a circuit of a DC / DC converter. Here, FIG. 2 shows the sealing resin 40 through the view for ease of understanding. FIG. 3 shows the semiconductor element 20, the plurality of electrodes 31, and the bonding layer 32 through the view for ease of understanding. In these figures, the semiconductor element 20 and the sealing resin 40 are shown by imaginary lines (two-dot chain lines).

[0012] In the description of the semiconductor device A10, the thickness direction z of the conductive member 10 is referred to as the "thickness direction z." The direction perpendicular to the thickness direction z is referred to as the "first direction x." The direction perpendicular to both the thickness direction z and the first direction x is referred to as the "second direction y." As shown in FIGS. 1 and 2, the semiconductor device A10 is rectangular when viewed along the thickness direction z. In addition, in the description of the semiconductor device A10, for convenience, the side in the second direction y where the multiple second leads 12 (described in detail later) are located is referred to as the "one side of the second direction y." The side in the second direction y where the multiple first leads 11 (described in detail later) are located is referred to as the "other side of the second direction y."

[0013] As shown in FIG. 2, the conductive member 10 has a semiconductor element 20 mounted thereon and serves as a terminal for mounting the semiconductor device A10 on a wiring board. As shown in FIGS. 9 to 12, a part of the conductive member 10 is covered with a sealing resin 40. The conductive member 10 has a main surface 101 and a back surface 102 facing opposite sides in a thickness direction z. The main surface 101 faces one side in the thickness direction z and faces the semiconductor element 20. The semiconductor element 20 is supported by the main surface 101. The main surface 101 is covered with the sealing resin 40. The back surface 102 faces the other side in the thickness direction z. The conductive member 10 is composed of a single lead frame. The lead frame is made of a material containing, for example, copper (Cu) or a copper alloy. The conductive member 10 includes a plurality of first leads 11, a plurality of second leads 12, and a pair of third leads 13.

[0014] As shown in FIG. 3 and FIG. 4, the first leads 11 are strip-shaped extending in the second direction y when viewed along the thickness direction z. The first leads 11 are arranged along the second direction y. In the example shown by the semiconductor device A10, the first leads 11 are composed of three terminals, namely, a first input terminal 11A, a second input terminal 11B, and an output terminal 11C. The first leads 11 are arranged in the order of the first input terminal 11A, the output terminal 11C, and the second input terminal 11B from one side to the other side in the second direction y. The first input terminal 11A and the second input terminal 11B receive DC power (voltage) to be converted in the semiconductor device A10. The first input terminal 11A is a positive terminal (P terminal). The second input terminal 11B is a negative terminal (N terminal). The output terminal 11C outputs AC power (voltage) converted by the switching circuit 212A configured in the semiconductor element 20.

[0015] As shown in FIG. 3, the first input terminal 11A is located between the multiple second leads 12 and the output terminal 11C in the second direction y. The output terminal 11C is located between the first input terminal 11A and the second input terminal 11B in the second direction y. Each of the first input terminal 11A and the output terminal 11C includes a main portion 111 and a pair of side portions 112. As shown in FIGS. 3 and 4, the main portion 111 extends in the first direction x. In the multiple first leads 11, the semiconductor element 20 is supported on the main surface 101 of the main portion 111. The pair of side portions 112 are connected to both ends of the main portion 111 in the first direction x. As shown in FIGS. 3, 4, 10, and 11, each of the pair of side portions 112 has a first end surface 112A. The first end surface 112A is connected to both the main surface 101 and the back surface 102 of the first lead 11, and faces the first direction x. The first end surface 112A is exposed from the sealing resin 40.

[0016] 3 and 4, in each of the first input terminal 11A and the output terminal 11C, the pair of side portions 112 are constricted in the second direction y. As a result, in each of the first input terminal 11A and the output terminal 11C, the dimension in the second direction y of each of the pair of first end faces 112A is smaller than the dimension in the second direction y of the main portion 111. Both ends in the second direction y of the pair of side portions 112 are in contact with the sealing resin 40.

[0017] As shown in FIG. 3, the second input terminal 11B is located on the other side of the second direction y than the output terminal 11C. Therefore, the second input terminal 11B is located on the other side of the multiple first leads 11 in the second direction y. The second input terminal 11B includes a main portion 111, a pair of side portions 112, and multiple protrusions 113. The multiple protrusions 113 protrude from the other side of the main portion 111 in the second direction y. The sealing resin 40 is filled between two adjacent protrusions 113. As shown in FIG. 9, each of the multiple protrusions 113 has a sub-end surface 113A. The sub-end surface 113A is connected to both the main surface 101 and the back surface 102 of the second input terminal 11B and faces the other side of the second direction y. The sub-end surface 113A is exposed from the sealing resin 40. As shown in FIG. 7, the multiple sub-end surfaces 113A are arranged at predetermined intervals along the first direction x.

[0018] 3 and 4, in each of the multiple first leads 11, the area of ​​the main surface 101 is larger than the area of ​​the back surface 102. In the example shown in semiconductor device A10, the areas of the back surfaces 102 of the first input terminal 11A and the output terminal 11C are equal to each other. The area of ​​the back surface 102 of the second input terminal 11B is larger than the areas of the back surfaces 102 of the first input terminal 11A and the output terminal 11C.

[0019] In each of the first input terminal 11A, the second input terminal 11B, and the output terminal 11C, the main surface 101 of the main portion 111 on which the semiconductor element 20 is supported may be plated with, for example, silver (Ag). Furthermore, in each of the first input terminal 11A, the second input terminal 11B, and the output terminal 11C, the back surface 102 exposed from the sealing resin 40, the pair of first end faces 112A, and the plurality of sub-end faces 113A may be plated with, for example, tin (Sn). Note that instead of tin plating, a plurality of metal platings may be employed in which nickel (Ni), palladium (Pd), and gold (Au) are layered in this order.

[0020] As shown in FIG. 3, the second leads 12 are located on one side of the first leads 11 in the second direction y. One of the second leads 12 is a ground terminal of the control circuit 212B configured in the semiconductor element 20. To each of the other second leads 12, power (voltage) for driving the control circuit 212B or an electric signal for transmitting to the control circuit 212B is input. As shown in FIG. 3, FIG. 4, and FIG. 9, each of the second leads 12 has a second end surface 121. The second end surface 121 is connected to both the main surface 101 and the back surface 102 of the second lead 12 and faces one side of the second direction y. The second end surface 121 is exposed from the sealing resin 40. As shown in FIG. 8, the second end surfaces 121 are arranged at predetermined intervals along the first direction x.

[0021] 3 and 4, in each of the multiple second leads 12, the area of ​​the main surface 101 is larger than the area of ​​the back surface 102. The areas of the back surfaces 102 of the multiple second leads 12 are all equal. The back surfaces 102 of the multiple second leads 12 on which the semiconductor element 20 is supported may be plated with silver, for example. Furthermore, the back surfaces 102 and second end surfaces 121 of the multiple second leads 12 exposed from the sealing resin 40 may be plated with tin, for example. Instead of tin plating, multiple metal platings may be used in which nickel, palladium, and gold are layered in this order.

[0022] As shown in FIG. 3, the pair of third leads 13 are located between the first lead 11 (first input terminal 11A) and the plurality of second leads 12 in the second direction y. The pair of third leads 13 are spaced apart from each other in the first direction x. An electric signal or the like to be transmitted to the control circuit 212B configured in the semiconductor element 20 is input to each of the pair of third leads 13. As shown in FIGS. 3, 4, and 12, each of the pair of third leads 13 has a third end surface 131. The third end surface 131 is connected to both the main surface 101 and the back surface 102, and faces the first direction x. The third end surface 131 is exposed from the sealing resin 40. The third end surface 131 is arranged along the second direction y together with the first end surfaces 112A of the plurality of first leads 11.

[0023] 3 and 4, in each of the pair of third leads 13, the area of ​​the main surface 101 is larger than the area of ​​the back surface 102. The main surface 101 of the pair of third leads 13 on which the semiconductor element 20 is supported may be plated with, for example, silver. Furthermore, the back surface 102 and the third end surface 131 of the pair of third leads 13 exposed from the sealing resin 40 may be plated with, for example, tin. Note that, instead of tin plating, multiple metal platings may be employed in which nickel, palladium, and gold are layered in this order.

[0024] As shown in FIG. 3 and FIGS. 9 to 12, the conductive member 10 has a plurality of recesses 14. The plurality of recesses 14 are recessed in the thickness direction z from the main surface 101 of the conductive member 10. As shown in FIGS. 13 and 14, each of the plurality of recesses 14 has a bottom surface 141 and an inner side surface 142. The bottom surface 141 faces the same side as the main surface 101 in the thickness direction z. The bottom surface 141 is located between the main surface 101 and the back surface 102 of the conductive member 10 in the thickness direction z. The inner side surface 142 is connected to the bottom surface 141 and the main surface 101. In the semiconductor device A10, the inner side surface 142 stands upright with respect to the bottom surface 141.

[0025] As shown in FIGS. 9 to 12, the semiconductor element 20 is bonded to the conductive member 10 (a plurality of first leads 11, a plurality of second leads 12, and a pair of third leads 13) by flip-chip mounting via a plurality of electrodes 31 and a bonding layer 32. Each of the plurality of electrodes 31 and the bonding layer 32 constitutes a bonding portion. The semiconductor element 20 is covered with a sealing resin 40. As shown in FIGS. 13 and 14, the semiconductor element 20 has an element body 21, a plurality of pads 22, and a surface protection film 23.

[0026] The element body 21 forms a main portion of the semiconductor element 20. As shown in Figures 13 and 14, the element body 21 has a substrate 211, a semiconductor layer 212, and a passivation film 213.

[0027] 13 and 14, the substrate 211 supports a semiconductor layer 212, a passivation film 213, a plurality of electrodes 31, and a surface protection film 23 therebelow. The substrate 211 is made of a semiconductor material. The semiconductor material is mainly composed of, for example, silicon (Si) or silicon carbide (SiC). The thickness of the substrate 211 is, for example, 100 μm or more and 300 μm or less.

[0028] As shown in FIGS. 9 to 12, the semiconductor layer 212 is located on the side of the substrate 211 facing the main surface 101 of the conductive member 10 in the thickness direction z. The semiconductor layer 212 is laminated on the substrate 211. The semiconductor layer 212 includes a plurality of types of p-type semiconductors and n-type semiconductors based on differences in the amount of elements to be doped. The semiconductor layer 212 includes a switching circuit 212A and a control circuit 212B that is conductive to the switching circuit 212A. The switching circuit 212A is a MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) or an IGBT (Insulated Gate Bipolar Transistor), for example. In the example shown in the semiconductor device A10, the switching circuit 212A is divided into two regions, a high-voltage region (upper arm circuit) and a low-voltage region (lower arm circuit). Each region is configured by one n-channel MOSFET. The control circuit 212B includes a gate driver for driving the switching circuit 212A, a bootstrap circuit corresponding to the high voltage region of the switching circuit 212A, and the like, and performs control for normally driving the switching circuit 212A. A wiring layer (not shown) is formed in the semiconductor layer 212. The switching circuit 212A and the control circuit 212B are mutually conductive through the wiring layer.

[0029] 13 and 14, the passivation film 213 covers the lower surface of the semiconductor layer 212. The passivation film 213 has electrical insulation properties. The passivation film 213 is composed of, for example, a silicon oxide film (SiO2) in contact with the lower surface of the semiconductor layer 212, and a silicon nitride film (Si3N4) laminated on the silicon oxide film. The passivation film 213 is provided with a plurality of openings 213A penetrating in the thickness direction z.

[0030] As shown in FIG. 13 and FIG. 14, the pads 22 face the main surface 101 of the conductive member 10. The pads 22 are arranged in contact with the semiconductor layer 212 of the element body 21. As a result, each of the pads 22 is electrically connected to either the switching circuit 212A of the semiconductor layer 212 or the control circuit 212B of the semiconductor layer 212. Each of the pads 22 contains aluminum (Al) or copper in its composition. Alternatively, each of the pads 22 may be a plurality of metal layers in which copper, nickel, and palladium are laminated in this order from the semiconductor layer 212 downward. Each of the pads 22 is in contact with the passivation film 213 of the element body 21. A portion of each of the pads 22 is exposed from the opening 213A of the passivation film 213.

[0031] 13 and 14, the surface protective film 23 covers the passivation film 213 of the element body 21. The surface protective film 23 is in contact with the passivation film 213 and the multiple pads 22. In the semiconductor device A10, each of the multiple electrodes 31 is separated from the surface protective film 23. Unlike this configuration, each of the multiple electrodes 31 may be in contact with the surface protective film 23. The surface protective film 23 has electrical insulation properties. The surface protective film 23 is made of a material containing, for example, polyimide.

[0032] The multiple electrodes 31 are formed on the multiple pads 22 of the semiconductor element 20, as shown in Fig. 13 and Fig. 14. The multiple electrodes 31 protrude from the multiple pads 22 in the thickness direction z on the opposite side to the element body 21 of the semiconductor element 20. As shown in Figs. 9 to 12, the multiple electrodes 31 are individually inserted into the multiple recesses 14 of the conductive member 10. In the semiconductor device A10, the composition of each of the multiple electrodes 31 includes copper.

[0033] Each of the multiple electrodes 31 is electrically connected to either the switching circuit 212A of the semiconductor layer 212 or the control circuit 212B of the semiconductor layer 212 via any of the multiple pads 22 of the semiconductor element 20. Each of the multiple electrodes 31 is bonded to the conductive member 10 via the bonding layer 32. The multiple electrodes 31 include multiple first electrodes 31A and multiple second electrodes 31B. Each of the multiple first electrodes 31A is electrically connected to the switching circuit 212A of the semiconductor layer 212 and is bonded to any of the multiple first leads 11. Each of the multiple second electrodes 31B is electrically connected to the control circuit 212B of the semiconductor layer 212 and is bonded to any of the multiple second leads 12 and a pair of third leads 13.

[0034] 13 and 14 , each of the multiple electrodes 31 has an opposing surface 311 and an outer surface 312. The opposing surface 311 faces a bottom surface 141 of one of the multiple recesses 14. The outer surface 312 is connected to the opposing surface 311 and faces an inner surface 142 of one of the multiple recesses 14.

[0035] The bonding layer 32 is disposed in the multiple recesses 14 of the conductive member 10, as shown in Fig. 13 and Fig. 14. The conductive member 10 and the multiple electrodes 31 are bonded to each other by the bonding layer 32. The bonding layer 32 has electrical conductivity. In the semiconductor device A10, the bonding layer 32 includes a metal. The metal has a composition including tin. The bonding layer 32 is, for example, a lead-free solder.

[0036] 13 and 14 , the bonding layer 32 is in contact with the bottom surfaces 141 of the multiple recesses 14 of the conductive member 10 and the opposing surfaces 311 of the multiple electrodes 31. Furthermore, the bonding layer 32 is in contact with the inner sides 142 of the multiple recesses 14 and the outer sides 312 of the multiple electrodes 31. The height h of each of the multiple electrodes 31 is greater than the depth d of each of the multiple recesses 14.

[0037] As shown in Fig. 9 to Fig. 12, the sealing resin 40 contacts the main surface 101 of the conductive member 10, and covers the semiconductor element 20 and the multiple electrodes 31. The sealing resin 40 includes a portion interposed between the main surface 101 and the semiconductor element 20. As shown in Fig. 5 to Fig. 8, the sealing resin 40 has a top surface 41, a bottom surface 42, a pair of first side surfaces 431, and a pair of second side surfaces 432. The sealing resin 40 is made of a material containing, for example, a black epoxy resin.

[0038] 9 to 12, the top surface 41 faces the same side as the main surface 101 of the conductive member 10 in the thickness direction z. As shown in Fig. 5 to 8, the bottom surface 42 faces the opposite side to the top surface 41. As shown in Fig. 4, rear surfaces 102 of the multiple first leads 11, rear surfaces 102 of the multiple second leads 12, and rear surfaces 102 of the pair of third leads 13 are exposed from the bottom surface 42.

[0039] 7 and 8, the pair of first side surfaces 431 are connected to both the top surface 41 and the bottom surface 42, and face the first direction x. The pair of first side surfaces 431 are spaced apart from each other in the second direction y. As shown in FIGS. 10 to 12, the first end surfaces 112A of the multiple first leads 11 and the third end surface 131 of the third lead 13 are exposed from each of the pair of first side surfaces 431 so as to be flush with the first side surfaces 431.

[0040] As shown in Fig. 5 and Fig. 6, the pair of second side surfaces 432 are connected to all of the top surface 41, the bottom surface 42, and the pair of first side surfaces 431, and face the second direction y. The pair of second side surfaces 432 are spaced apart from each other in the first direction x. As shown in Fig. 9, the second end surfaces 121 of the multiple second leads 12 are exposed from the second side surface 432 located on one side in the second direction y so as to be flush with the second side surface 432. The multiple sub-end surfaces 113A of the second input terminal 11B (first lead 11) are exposed from the second side surface 432 located on the other side in the second direction y so as to be flush with the second side surface 432.

[0041] <First Modification> Next, a semiconductor device A11, which is a modified example of the semiconductor device A10, will be described with reference to Fig. 15. Here, the cross-sectional position of Fig. 15 is the same as that of Fig. 13.

[0042] As shown in FIG. 15, the semiconductor device A11 has a different structure of the bonding layer 32 from that of the semiconductor device A10. In the semiconductor device A11, the bonding layer 32 includes a metal part 32A and an insulating part 32B. The metal part 32A is a bond of sintered metal particles, that is, a sintered body. The composition of the sintered body includes silver. The sintered body is obtained by sintering metal particles under atmospheric pressure. In addition, the metal part 32A may be metal particles that have not been sintered. The composition of the metal particles includes silver. The insulating part 32B is a part of the bonding layer 32 excluding the metal part 32A. At least a part of the insulating part 32B includes a resin. The resin is made of a material that includes a synthetic resin as a binder. The synthetic resin is a thermosetting resin such as an epoxy resin. The Young's modulus of the resin is smaller than that of the metal part 32A. The insulating part 32B may be made of only resin or may include a mixture of resin and voids. The volume of the insulating portion 32B is 15% or more and 35% or less of the entire volume of the bonding layer 32.

[0043] <Second Modification> Next, a semiconductor device A12, which is a modified example of the semiconductor device A10, will be described with reference to Fig. 16. The cross-sectional position of Fig. 16 is the same as that of Fig. 13.

[0044] 16, the semiconductor device A12 differs from the semiconductor device A10 in the configuration of the bonding layer 32. In the semiconductor device A12, the bonding layer 32 has a protruding portion 321. The protruding portion 321 is located outside the multiple recesses 14 of the conductive member 10. The protruding portion 321 contacts the outer surfaces 312 of the multiple electrodes 31 and the main surface 101 of the conductive member 10.

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

[0046] The semiconductor device A10 includes a conductive member 10 having a plurality of recesses 14 recessed from a main surface 101 in a thickness direction z, and a plurality of electrodes 31 protruding from a plurality of pads 22 of a semiconductor element 20 in the thickness direction z. The plurality of electrodes 31 are individually inserted into the plurality of recesses 14. The semiconductor device A10 further includes a bonding layer 32 having electrical conductivity and disposed within the plurality of recesses 14. The conductive member 10 and the plurality of electrodes 31 are bonded by the bonding layer 32. With this configuration, in a step of bonding the plurality of electrodes 31 to the conductive member 10 via the bonding layer 32 in the manufacturing process of the semiconductor device A10, the bonding layer 32 is suppressed from spreading along the main surface 101 of the conductive member 10, thereby preventing a short circuit of the plurality of electrodes 31. Furthermore, in each of the plurality of recesses 14, the bonding layer 32 is restrained by the conductive member 10 and the plurality of electrodes 31, thereby reducing thermal strain of the bonding layer 32 caused by heat generated from the semiconductor element 20. This can suppress the occurrence of cracks in the bonding layer 32. Therefore, according to the semiconductor device A10, it is possible to prevent the plurality of electrodes 31 from shorting out, while suppressing the occurrence of cracks in the bonding layer 32.

[0047] The bonding layer 32 is in contact with the bottom surfaces 141 of the multiple recesses 14 of the conductive member 10 and the opposing surfaces 311 of the multiple electrodes 31. Furthermore, the bonding layer 32 is in contact with the inner surfaces 142 of the multiple recesses 14 and the outer surfaces 312 of the multiple bonding layers 32. This can improve the bonding strength of the multiple electrodes 31 to the conductive member 10.

[0048] In the semiconductor device A11, the bonding layer 32 has a metal part 32A and an insulating part 32B. The metal part 32A is a sintered body. At least a part of the insulating part 32B contains a resin. In this case, by setting the Young's modulus of the insulating part 32B to be smaller than the Young's modulus of the metal part 32A, it is possible to effectively reduce the thermal stress acting on the metal part 32A due to the heat generated from the semiconductor element 20. This contributes to suppressing the occurrence of cracks in the metal part 32A.

[0049] In the semiconductor device A11, the volume of the insulating portion 32B of the bonding layer 32 is preferably 15% or more and 35% or less of the total volume of the bonding layer 32. This allows the effect of reducing the thermal stress acting on the metal portion 32A of the bonding layer 32 to be fully exerted. On the other hand, when the volume of the insulating portion 32B is less than 15% of the total volume of the bonding layer 32, the effect of reducing the thermal stress acting on the metal portion 32A is less likely to be exerted. On the other hand, when the volume of the insulating portion 32B exceeds 35% of the total volume of the bonding layer 32, this is not preferable because it causes an increase in the electrical resistance of the bonding layer 32.

[0050] In the semiconductor device A12, the bonding layer 32 has a protruding portion 321. The protruding portion 321 is located outside the multiple recesses 14 of the conductive member 10. The protruding portion 321 contacts the outer surfaces 312 of the multiple electrodes 31 and the main surface 101 of the conductive member 10. Due to the presence of the protruding portion 321, the multiple recesses 14 of the conductive member 10 are filled with the bonding layer 32. This means that the bonding state of the multiple electrodes 31 to the conductive member 10 is good. Furthermore, by appropriately adjusting the size of the protruding portion 321, it is possible to reliably prevent the multiple electrodes 31 from being short-circuited.

[0051] The semiconductor device A10 further includes a sealing resin 40 that contacts the main surface 101 of the conductive member 10 and covers the semiconductor element 20 and the electrodes 31. The sealing resin 40 includes a portion that is interposed between the main surface 101 and the semiconductor element 20. This can improve the dielectric strength of the semiconductor device A10. To achieve this configuration, as shown in FIG. 13 and FIG. 14, it is preferable that the height h of each of the electrodes 31 is greater than the depth d of each of the recesses 14 of the conductive member 10. This ensures that a gap is provided between the main surface 101 and the semiconductor element 20 in the thickness direction z. In addition, the recesses 14 serve as a means for suppressing the positional deviation of the electrodes 31 with respect to the conductive member 10 during the manufacture of the semiconductor device A10.

[0052] Each of the electrodes 31 has a length smaller than that of a bonding wire and a cross-sectional area larger than that of the bonding wire. Therefore, the parasitic resistance between the first lead 11 and the switching circuit 212A can be reduced compared to the case where the first lead 11 and the pads 22 of the semiconductor element 20 are connected by a bonding wire. When the parasitic resistance is reduced, the effect of reducing the on-resistance and noise in the switching circuit 212A is obtained.

[0053] A switching circuit 212A is configured in the semiconductor layer 212 of the element body 21 of the semiconductor element 20. At least one of the multiple electrodes 31 is electrically connected to the switching circuit 212A. Meanwhile, the back surfaces 102 of the multiple first leads 11 included in the conductive member 10 and to which at least one of the multiple electrodes 31 is joined are exposed from the bottom surface 42 of the sealing resin 40. This allows heat generated from the semiconductor element 20 by driving the switching circuit 212A to be efficiently dissipated to the outside when the semiconductor device A10 is used.

[0054] Each of the multiple first leads 11 has a main portion 111 extending in a first direction x and a pair of side portions 112 connected to both ends of the main portion 111 in the first direction x. Each of the pair of side portions 112 has a first end surface 112A facing the first direction x and exposed from a first side surface 431 of the sealing resin 40. Each of the pair of first end surfaces 112A is flush with the first side surface 431. In the second direction y, the dimension b of each of the pair of first end surfaces 112A is smaller than the dimension B of the back surface 102 of the main portion 111. This allows the area of ​​each of the pair of first end surfaces 112A to be smaller than the area of ​​the corresponding surface in a conventional QFN semiconductor device. Therefore, when the semiconductor device A10 is manufactured by dividing the semiconductor device A10 into individual pieces by blade dicing, the generation of metal burrs on the pair of first end surfaces 112A is suppressed. When the generation of metal burrs is suppressed, the mountability of the semiconductor device A10 on the wiring board can be improved.

[0055] 3 and 4, in each of the multiple first leads 11 (first input terminal 11A and output terminal 11C), the pair of side portions 112 are constricted in the second direction y. As a result, in each of the first input terminal 11A and the output terminal 11C, the dimension in the second direction y of each of the pair of first end faces 112A is smaller than the dimension in the second direction y of the main portion 111. Both ends in the second direction y of the pair of side portions 112 are in contact with the sealing resin 40. This configuration makes it possible to prevent the multiple first leads 11 from slipping out of the pair of first side surfaces 431 of the sealing resin 40.

[0056] The second input terminal 11B includes a plurality of protruding portions 113 protruding from the other side in the second direction y of the main portion 111. Each of the plurality of protruding portions 113 has a sub-end surface 113A facing the second direction y. The sub-end surfaces 113A are exposed from a second side surface 432 of the sealing resin 40 located on the other side in the second direction y. This results in a configuration in which the second input terminal 11B contacts the sealing resin 40 on the other side in the second direction y. This makes it possible to prevent the second input terminal 11B from slipping out of the second side surface 432 located on the other side in the second direction y.

[0057] In each of the multiple first leads 11, the area of ​​the main surface 101 is larger than the area of ​​the back surface 102. This results in a configuration in which the multiple first leads 11 contact the sealing resin 40 on the side toward which the back surface 102 in the thickness direction z faces. This makes it possible to prevent the multiple first leads 11 from slipping out of the bottom surface 42 of the sealing resin 40. Furthermore, it is possible to ensure a larger area of ​​the main surface 101 of each of the multiple first leads 11 to which at least any one of the multiple electrodes 31 is joined. This makes it possible to further increase the number of the multiple electrodes 31 joined to the multiple first leads 11.

[0058] The conductive member 10 further includes a plurality of second leads 12 to which at least one of the plurality of electrodes 31 is joined. In each of the plurality of second leads 12, the area of ​​the main surface 101 is larger than the area of ​​the back surface 102. Therefore, similar to the relationship between the main surface 101 and the back surface 102 of the first lead 11 described above, the plurality of second leads 12 can be prevented from slipping out of the bottom surface 42 of the sealing resin 40. Furthermore, the area of ​​each of the plurality of second leads 12 to which at least one of the plurality of electrodes 31 is joined can be further secured. This makes it possible to further increase the number of the plurality of electrodes 31 joined to the plurality of second leads 12.

[0059] Second Embodiment A semiconductor device A20 according to a second embodiment of the present disclosure will be described with reference to Fig. 17. In this figure, the same or similar elements as those of the semiconductor device A10 described above are denoted by the same reference numerals, and duplicated explanations will be omitted. Here, the cross-sectional position of Fig. 17 is the same as that of Fig. 13.

[0060] The semiconductor device A20 differs from the semiconductor device A10 in the configuration of the multiple electrodes 31 described above.

[0061] As shown in FIG. 17, each of the electrodes 31 has a main portion 313 and a sub-portion 314. The main portion 313 is formed on a pad 22 of the semiconductor element 20. The main portion 313 includes copper. The sub-portion 314 covers the main portion 313. The sub-portion 314 includes a first layer 314A and a second layer 314B. The first layer 314A covers the main portion 313. The first layer 314A includes nickel. The second layer 314B covers the first layer 314A. The second layer 314B includes palladium. The sub-portion 314 may be composed of a single metal layer, in addition to being composed of the first layer 314A and the second layer 314B. In this case, the metal layer includes either palladium or nickel.

[0062] <Modification> Next, a semiconductor device A21, which is a modified example of the semiconductor device A20, will be described with reference to Fig. 18. The cross-sectional position of Fig. 18 is the same as that of Fig. 13.

[0063] As shown in FIG. 18, the semiconductor device A21 differs from the semiconductor device A20 in the configuration of the multiple recesses 14 of the conductive member 10. In the semiconductor device A21, each of the multiple recesses 14 has a coating layer 143. The coating layer 143 is a metal layer that covers the conductive member 10 in each of the multiple recesses 14. In each of the multiple recesses 14, the bottom surface 141 and the inner side surface 142 form the surface of the coating layer 143. The coating layer 143 is made of a single metal layer or multiple metal layers. When the coating layer 143 is made of a single metal layer, the composition of the metal layer contains either palladium or nickel. When the coating layer 143 is made of multiple metal layers, the composition of the coating layer 143 is made of a metal layer that covers the conductive member 10 and contains nickel in its composition, and a metal layer that covers the metal layer and contains palladium in its composition.

[0064] Next, the effects of the semiconductor device A20 will be described.

[0065] The semiconductor device A20 includes a conductive member 10 having a plurality of recesses 14 recessed from a main surface 101 in a thickness direction z, and a plurality of electrodes 31 protruding in the thickness direction z from a plurality of pads 22 of a semiconductor element 20. The plurality of electrodes 31 are individually inserted into the plurality of recesses 14. The semiconductor device A10 further includes a bonding layer 32 that is conductive and disposed within the plurality of recesses 14. The conductive member 10 and the plurality of electrodes 31 are bonded to each other by the bonding layer 32. Therefore, the semiconductor device A20 also makes it possible to prevent short circuits of the plurality of electrodes 31 while suppressing the occurrence of cracks in the bonding layer 32.

[0066] In the semiconductor device A20, each of the multiple electrodes 31 has a main portion 313 formed on the pad 22 of the semiconductor element 20 and a sub-portion 314 covering the main portion 313. The main portion 313 contains copper. The sub-portion 314 contains palladium. With this configuration, in the process of bonding the multiple electrodes 31 to the conductive member 10 via the bonding layer 32 in the manufacturing process of the semiconductor device A20, the thermal shock acting on the main portion 313 is reduced by the sub-portion 314. This makes it possible to protect the main portion 313. Furthermore, when the bonding layer 32 contains tin, the wettability of the bonding layer 32 to the multiple electrodes 31 is good. This ensures a sufficient contact area between the multiple electrodes 31 and the bonding layer 32. In order to more effectively exert this effect, it is preferable that sub-part 314 has a configuration including first layer 314A covering main part 313 and containing nickel in its composition, and second layer 314B covering first layer 314A and containing palladium in its composition.

[0067] In the semiconductor device A21, each of the multiple recesses 14 of the conductive member 10 has a coating layer 143. This configuration can reduce thermal shock acting on the conductive member 10 in the process of bonding the multiple electrodes 31 to the conductive member 10 via the bonding layer 32 during the manufacturing process of the semiconductor device A20. This can protect the conductive member 10. Furthermore, when the composition of the bonding layer 32 contains tin, the wettability of the bonding layer 32 with respect to the conductive member 10 is improved. This ensures a sufficient contact area between the conductive member 10 and the bonding layer 32.

[0068] Third Embodiment A semiconductor device A30 according to a third embodiment of the present disclosure will be described with reference to Fig. 19. In this figure, the same or similar elements as those of the semiconductor device A10 described above are denoted by the same reference numerals, and duplicated explanations will be omitted. Here, the cross-sectional position of Fig. 19 is the same as that of Fig. 13.

[0069] The semiconductor device A30 differs from the semiconductor device A10 in the configuration of the multiple recesses 14 of the conductive member 10.

[0070] 19, in each of the multiple recesses 14 of the conductive member 10, the inner side surface 142 is inclined with respect to the bottom surface 141 and the main surface 101 of the conductive member 10. Therefore, the area of ​​the inner side surface 142 is larger than the area of ​​each of the multiple recesses 14 of the semiconductor device A10. The cross-sectional area of ​​each of the multiple recesses 14 along a direction perpendicular to the thickness direction z gradually decreases from the main surface 101 toward the bottom surface 141.

[0071] <Modification> Next, a semiconductor device A31, which is a modification of the semiconductor device A30, will be described with reference to Fig. 20. The cross-sectional position of Fig. 20 is the same as that of Fig. 13.

[0072] 20, the semiconductor device A31 differs from the semiconductor device A30 in the configuration of the multiple electrodes 31. In the semiconductor device A31, each of the multiple electrodes 31 has a recessed portion 315. The recessed portion 315 is recessed from the opposing surface 311 toward the side where the semiconductor element 20 is located in the thickness direction z. The bonding layer 32 is in contact with the recessed portion 315.

[0073] Next, the effects of the semiconductor device A30 will be described.

[0074] The semiconductor device A30 includes a conductive member 10 having a plurality of recesses 14 recessed from a main surface 101 in a thickness direction z, and a plurality of electrodes 31 protruding in the thickness direction z from a plurality of pads 22 of a semiconductor element 20. The plurality of electrodes 31 are individually inserted into the plurality of recesses 14. The semiconductor device A10 further includes a bonding layer 32 that is conductive and disposed within the plurality of recesses 14. The conductive member 10 and the plurality of electrodes 31 are bonded to each other by the bonding layer 32. Therefore, the semiconductor device A30 also makes it possible to prevent short circuits of the plurality of electrodes 31 while suppressing the occurrence of cracks in the bonding layer 32.

[0075] In the semiconductor device A30, the inner side surface 142 of the plurality of recesses 14 of the conductive member 10 is inclined with respect to each of the bottom surface 141 of the plurality of recesses 14 and the main surface 101 of the conductive member 10. This increases the contact area of ​​the conductive member 10 with the bonding layer 32, thereby further improving the bonding strength of the plurality of electrodes 31 with respect to the conductive member 10. The cross-sectional area of ​​each of the plurality of recesses 14 in a direction perpendicular to the thickness direction z gradually decreases from the main surface 101 toward the bottom surface 141. This distributes the thermal stress acting on the bonding layer 32, and the flow of the thermal stress along the thickness direction z becomes smoother. This contributes to more effective suppression of cracks in the bonding layer 32.

[0076] In the semiconductor device A31, each of the multiple electrodes 31 has a recessed portion 315 recessed from the opposing surface 311 in the thickness direction z. The bonding layer 32 is in contact with the recessed portion 315. This increases the contact area of ​​the multiple electrodes 31 with the bonding layer 32, thereby further improving the bonding strength of the multiple electrodes 31 with the conductive member 10. Furthermore, the bonding layer 32 generates an anchor effect with respect to the multiple electrodes 31. This contributes to improving the bonding strength of the multiple electrodes 31 with the conductive member 10.

[0077] The present disclosure is not limited to the above-described embodiment. The specific configuration of each part of the present disclosure can be freely designed in various ways.

[0078] The technical configuration of the semiconductor device provided by the present disclosure is described below. [Appendix 1] A conductive member having a main surface facing one side in a thickness direction; a semiconductor element having a plurality of pads facing said main surface; a plurality of electrodes protruding from the plurality of pads to the other side in the thickness direction; the conductive member has a plurality of recesses recessed from the main surface to the other side in the thickness direction, a bonding layer having electrical conductivity and disposed within the plurality of recesses; The plurality of electrodes are individually inserted into the plurality of recesses, The conductive member and the plurality of electrodes are joined by the joining layer. [Appendix 2] the recess has a bottom surface facing the same side as the main surface in the thickness direction, The electrode has an opposing surface facing the bottom surface, 2. The semiconductor device according to claim 1, wherein the bonding layer is in contact with the bottom surface and the opposing surface. [Appendix 3] the recess has an inner side surface connected to the bottom surface and the main surface, the electrode has an outer surface connected to the opposing surface and facing the inner surface; 3. The semiconductor device according to claim 2, wherein the bonding layer is in contact with the inner surface and the outer surface. [Appendix 4] 4. The semiconductor device according to claim 3, wherein the inner side surface is inclined with respect to each of the bottom surface and the main surface. [Appendix 5] 5. The semiconductor device according to claim 4, wherein a cross-sectional area of ​​the recess in a direction perpendicular to the thickness direction gradually decreases from the main surface to the bottom surface. [Appendix 6] the electrode has a recessed portion recessed from the opposing surface to the one side in the thickness direction, 6. The semiconductor device according to claim 3, wherein the bonding layer is in contact with the recess. [Appendix 7] The bonding layer includes a metal, 7. The semiconductor device according to claim 1, wherein the metal composition includes tin. [Appendix 8] the bonding layer has a metal portion and an insulating portion, 7. The semiconductor device according to claim 1, wherein at least a portion of the insulating portion contains a resin. [Appendix 9] The semiconductor device according to claim 8, wherein the metal part is a sintered body. [Appendix 10] 10. The semiconductor device according to claim 8, wherein the insulating portion includes a gap. [Appendix 11] 11. The semiconductor device according to claim 8, wherein the metal portion has a composition including silver. [Appendix 12] 12. The semiconductor device according to claim 7, wherein the electrode has a composition including copper. [Appendix 13] The electrode has a main portion formed on the pad and a sub-portion covering the main portion, The composition of the main portion includes copper, 13. The semiconductor device of claim 12, wherein the sub-portion has a composition including palladium. [Appendix 14] The sub-portion has a first layer covering the main portion and a second layer covering the first layer, The composition of the first layer includes nickel, 14. The semiconductor device of claim 13, wherein the second layer has a composition including palladium. [Appendix 15] a sealing resin in contact with the main surface and covering the semiconductor element and the plurality of electrodes; 15. The semiconductor device according to claim 1, wherein the sealing resin includes a portion interposed between the main surface and the semiconductor element. [Appendix 16] the conductive member has a back surface facing the opposite side to the main surface in the thickness direction, 16. The semiconductor device according to claim 15, wherein the back surface is exposed from the sealing resin. [Explanation of symbols]

[0079] A10, A20, A30: Semiconductor device 10: Conductive material 101: Main surface 102: Back side 11: First Lead 11A: First input terminal 11B: 2nd input terminal 11C: Output terminal 111: Main part 112: Side 112A: First end surface 113:Protrusion 113A: Minor end face 12: 2nd Lead 121: Second end surface 13: 3rd Lead 131: Third end surface 14: Recess 141: Bottom 142: Inner surface 143: Covering layer 20: Semiconductor element 21: Element body 211: Substrate 211A: Base 212: Semiconductor layer 212A: Switching circuit 212B: Control circuit 213: Passivation film 213A:Aperture 22: Pad 23: Surface protective film 31: Electrode 31A: 1st electrode 31B: 2nd electrode 311: Opposite surface 312:Outer surface 313: Main part 314: Subpart 314A: 1st layer 314B: 2nd layer 315: Indentation 32: Bonding layer 32A: Metal part 32B: Insulation section 321: Protruding part 40: Sealing resin 41:Top surface 42: Bottom 431:1st side 432:Second side h:height d:Depth z: thickness direction x: 1st direction y: second direction

Claims

1. A conductive member having a main surface facing one side in a thickness direction; a semiconductor element having a plurality of pads facing said main surface; a plurality of electrodes protruding from the plurality of pads to the other side in the thickness direction; a bonding layer having electrical conductivity and bonding the conductive member and the plurality of electrodes; the conductive member has a plurality of recesses recessed from the main surface, the bonding layer is accommodated in each of the plurality of recesses, the plurality of electrodes are individually inserted into the plurality of recesses, Each of the plurality of recesses is defined by a bottom surface facing the same side as the main surface in the thickness direction, and an inner side surface connected to the bottom surface and the main surface, Each of the plurality of electrodes has an opposing surface facing the opposite side to the main surface in the thickness direction and opposing the bottom surface, and an outer surface connected to the opposing surface and opposing the inner surface, the bonding layer is in contact with the bottom surface, the inner side surface, the opposing surface, and the outer side surface; the bonding layer has an end surface facing the same side as the main surface in the thickness direction, the end surface is away from the main surface on a side where the bottom surface is located with respect to the main surface in the thickness direction, the inner surface includes a first region exposed from the bonding layer; the outer surface includes a second region exposed from the bonding layer; The semiconductor device, wherein each of the first region and the second region is located between the main surface and the end surface in the thickness direction.

2. The semiconductor device according to claim 1 , wherein said inner side surface is inclined with respect to each of said bottom surface and said main surface.

3. 3. The semiconductor device according to claim 2, wherein a cross-sectional area of ​​each of said plurality of recesses along a direction perpendicular to said thickness direction gradually decreases from said main surface to said bottom surface.

4. Each of the plurality of electrodes has a recessed portion recessed from the opposing surface, 4. The semiconductor device according to claim 1, wherein the bonding layer penetrates into the recess.

5. The bonding layer includes a metal, 5. The semiconductor device according to claim 1, wherein said metal composition includes tin.

6. the bonding layer has a metal portion and an insulating portion, The semiconductor device according to claim 1 , wherein at least a portion of said insulating portion includes a resin.

7. The semiconductor device according to claim 6 , wherein the metal portion is a sintered body.

8. The semiconductor device according to claim 6 , wherein the insulating portion includes a gap.

9. 9. The semiconductor device according to claim 6, wherein the metal portion has a composition containing silver.

10. 10. The semiconductor device according to claim 5, wherein the composition of said electrode contains copper.

11. The electrode has a main portion formed on the pad and a sub-portion covering the main portion, The composition of the main portion includes copper, The semiconductor device according to claim 10 , wherein the composition of the sub-portion includes palladium.

12. The sub-portion has a first layer covering the main portion and a second layer covering the first layer, The composition of the first layer includes nickel, The semiconductor device according to claim 11 , wherein the composition of the second layer includes palladium.

13. a sealing resin in contact with the main surface and covering the semiconductor element and the plurality of electrodes; 13. The semiconductor device according to claim 1, wherein the sealing resin includes a portion interposed between the main surface and the semiconductor element.

14. the conductive member has a back surface facing the opposite side to the main surface in the thickness direction, The semiconductor device according to claim 13 , wherein the back surface is exposed from the sealing resin.

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