Lead frame and semiconductor device

Abstract

A lead frame (1) includes a heat sink (10) having a mounting surface (11) on which a semiconductor element (30) is mounted, and a unit lead frame (20) having a lead (21). A first groove portion (13) is formed in a peripheral portion of the mounting surface (11) of the heat sink. The unit lead frame (20) has a protrusion portion (22) having a front end portion (22a) shaped to correspond to the first groove portion (13). The heat sink (10) is fixed to the unit lead frame (20) by fitting the protrusion portion (22) into the first groove portion (13).

Description

Technical Field

[0001] This disclosure relates to lead frames and semiconductor devices. Background Technology

[0002] For example, in a semiconductor device that houses a semiconductor element that controls a large current, such as a power semiconductor element, a structure is known in which a heat sink is attached to the lead frame body and the semiconductor element is directly mounted on the heat sink in order to efficiently dissipate the heat generated from the semiconductor element.

[0003] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2001-144242 Summary of the Invention

[0004] (a) Technical problems to be solved Traditionally, the lead frame body and the heat sink were joined by riveting, which required a large area for this riveting process. This extra space required for the riveting area inside the semiconductor device could potentially be disadvantageous in semiconductor device manufacturing.

[0005] The purpose of this disclosure is to provide a small-area lead frame and semiconductor device required for the connection between the lead frame body and the heat sink.

[0006] (II) Technical Solution One embodiment of the lead frame includes: a heat sink having a mounting surface for mounting semiconductor devices; and a unit lead frame having leads. A first groove is formed on the periphery of the mounting surface on the heat sink. The unit lead frame has a protrusion, the front end of which has a shape corresponding to the first groove. The heat sink is fixed to the unit lead frame by fitting the protrusion into the first groove.

[0007] In another embodiment, a semiconductor device includes: the lead frame and a semiconductor element mounted on the mounting surface.

[0008] (III) Beneficial Effects According to one embodiment, the area required for the connection between the lead frame body and the heat sink is small. Furthermore, the effects described herein are not necessarily limited to these, and may include any of the effects described in this disclosure. Attached Figure Description

[0009] Figure 1A These are top and side views illustrating an example of a heat sink implementation.

[0010] Figure 1BThis is an enlarged top view showing an example of the lead frame body of the embodiment.

[0011] Figure 2A This is an enlarged top view showing an example of a lead frame in an embodiment.

[0012] Figure 2B yes Figure 2A The sectional view along line AA is shown.

[0013] Figure 3A This is an enlarged top view showing an example of the joint area between the heat sink and the unit lead frame in an embodiment.

[0014] Figure 3B yes Figure 3A The sectional view along the BB line is shown.

[0015] Figure 4A This is a top view illustrating an example of a semiconductor device according to an embodiment.

[0016] Figure 4B yes Figure 4A The sectional view along the CC line is shown.

[0017] Figure 5A This is an enlarged cross-sectional view showing an example of the joint area between the heat sink and the unit lead frame in a modified embodiment 1.

[0018] Figure 5B This is an enlarged top view showing an example of the joint area between the heat sink and the unit lead frame in Modified Example 2 of the embodiment.

[0019] Figure 6A This is an enlarged top view showing an example of the joint area between the heat sink and the unit lead frame in Modified Example 3 of the embodiment.

[0020] Figure 6B This is an enlarged top view showing another example of the joint area between the heat sink and the unit lead frame in Modified Example 3 of the embodiment.

[0021] Figure 7A This is an enlarged top view showing an example of the joint area between the heat sink and the unit lead frame in Modified Example 4 of the embodiment.

[0022] Figure 7B This is an enlarged top view showing an example of the joint area between the heat sink and the unit lead frame in Modified Example 5 of the embodiment.

[0023] Figure 8A This is an enlarged top view showing an example of the joint area between the heat sink and the unit lead frame in Modified Example 6 of the embodiment.

[0024] Figure 8BThis is an enlarged top view showing an example of the joint area between the heat sink and the unit lead frame in Modified Example 7 of the embodiment. Detailed Implementation

[0025] The lead frame and semiconductor device disclosed in this application will now be described with reference to the accompanying drawings. Furthermore, this disclosure is not limited to the embodiments shown below.

[0026] Additionally, it should be noted that the accompanying drawings are schematic, and the dimensional relationships and ratios of the elements may sometimes differ from reality. Furthermore, the accompanying drawings may also contain elements with different dimensional relationships and ratios.

[0027] <Heat Discharge Plate> First, refer to Figure 1A For the lead frame 1 forming the embodiment (refer to Figure 2A The heat sink 10 will be described in detail. Figure 1A These are a top view and a side view illustrating an example of the heat sink 10 in an embodiment.

[0028] The heat sink 10 serves as the semiconductor device 100 described later (see reference). Figure 4A The chip pads function as chip solder pads. For example... Figure 1A As shown, the heat sink 10 in this embodiment is flat. One main surface of the heat sink 10 is a mounting surface 11, on which a semiconductor element 30 (see reference 10) is mounted. Figure 4A Additionally, in the heat sink 10, the main surface opposite to the mounting surface 11 is referred to as the back surface 12.

[0029] The heat sink 10 is, for example, rectangular in shape when viewed from above. In the heat sink 10, first grooves 13 are formed on the periphery of the mounting surfaces 11 that meet two opposite sides. The two first grooves 13 are, for example, formed at a point symmetrical about the center X1 of the heat sink 10. The first grooves 13 are, for example, formed by cutting a cuboid from the periphery of the mounting surface 11, or they can be formed by stamping or etching.

[0030] The heat sink 10 is formed of a metal with good thermal conductivity, such as copper or a copper alloy. Furthermore, the heat sink 10 is not limited to a rectangular shape when viewed from above, but can also be a variety of planar shapes.

[0031] <Leader Frame Body> Next, refer to Figure 1B For the lead frame 1 forming the embodiment (refer to Figure 2A The lead frame body 20 is described below. Figure 1B This is an enlarged top view showing an example of the lead frame body 20 of the embodiment.

[0032] The lead frame body 20 of the embodiment is a component formed by stamping, etching or other processes on a metal plate made of copper, copper alloy or iron-nickel alloy to form a predetermined pattern.

[0033] The lead frame body 20 of the embodiment is, for example, strip-shaped when viewed from above. Multiple unit lead frames 20A are arranged along the long side of the lead frame body 20. Furthermore, in this disclosure, the lead frame body 20 may also have multiple unit lead frames 20A arranged not only along the long side but also along the width direction.

[0034] like Figure 1B As shown, the unit lead frame 20A has a plurality of leads 21 and a plurality of protrusions 22. In addition, adjacent unit lead frames 20A are connected to each other by connecting rods 23.

[0035] Lead 21 serves as semiconductor device 100 (see reference) Figure 4A The connecting terminals function as such. Multiple leads 21 are located, for example, around the central part X2 in the unit lead frame 20A. The leads 21 are supported on the connecting rod 23, for example, by connecting ribs 24.

[0036] The protrusion 22 is supported, for example, on the connecting rod 23 and extends from the connecting rod 23 toward the inner side (e.g., the central part X2 side) of the unit lead frame 20A. For example, a protrusion 22 is provided on each of the connecting rods 23 on both sides that are connected to a unit lead frame 20A.

[0037] The front end portion 22a of the protrusion 22 (refer to) Figure 3A From above, it is connected to heat sink 10 (see reference). Figure 1A The first groove 13 (refer to) Figure 1A The corresponding shape.

[0038] Guide holes 25 are arranged on both sides of the strip-shaped lead frame body 20. The guide holes 25 are used for positioning the lead frame body 20 and the lead frame 1 in various processes.

[0039] <Leader Frame> Next, refer to Figures 2A to 3B The detailed structure of the lead frame 1 in the embodiment will be described. Figure 2A This is an enlarged top view showing an example of the lead frame 1 in the embodiment. Figure 2B yes Figure 2A The sectional view along line AA is shown.

[0040] In this embodiment, the lead frame 1 is, for example, strip-shaped in top view, and multiple unit lead frame structures 1A are arranged along its long side. This unit lead frame structure 1A is associated with the semiconductor device 100 manufactured using the lead frame 1 (see reference 1). Figure 4A (Corresponding parts)

[0041] Adjacent unit lead frame structures 1A are connected to each other by connecting rods 23. Furthermore, in this disclosure, multiple unit lead frame structures 1A may be formed not only along the long side of the lead frame 1, but also arranged along the width direction.

[0042] like Figure 2A As shown, the unit lead frame structure 1A has a heat sink 10 and a unit lead frame 20A. In the unit lead frame structure 1A, for example, the center X1 of the heat sink 10 (refer to...) Figure 1A ) and the central part X2 of the unit lead frame 20A (refer to Figure 1B ( ) Located in the same or similar position when viewed from above.

[0043] In addition, in the unit lead frame structure 1A, a plurality of leads 21 and a plurality of protrusions 22 are located, for example, around the heat sink 10.

[0044] In this implementation, it can also be, as follows: Figure 2A as well as Figure 2B As shown, the heat sink 10 is fixed to the unit lead frame 20A by fitting the front end 22a of the protrusion 22 in the unit lead frame 20A into the first groove 13 of the heat sink 10.

[0045] Therefore, compared with the case where the heat sink 10 is fixed to the lead frame body 20 by riveting, the area required for the connection between the lead frame body 20 and the heat sink 10 is smaller.

[0046] For example, in semiconductor element 30 of the same specifications (refer to...) Figure 4A When mounted on the heat sink 10, the width of the joint area between the lead frame body 20 and the heat sink 10 required for riveting in the prior art is 2.11 mm. In contrast, in this disclosure, the required joint area width is reduced to 0.55 mm.

[0047] Furthermore, in existing riveting processes, stamping is required to form the embossing needed for riveting by making the heat sink 10 into a large convex shape. However, in this embodiment, the first groove 13 is formed by performing conventional stamping, etching, or other processes on the heat sink 10.

[0048] That is, in the embodiment, when the heat sink 10 is manufactured by various stamping processes, etching processes, etc., a first groove 13 is formed on the heat sink 10, thus simplifying the manufacturing process of the heat sink 10.

[0049] Furthermore, in the existing riveting process, the heat sink 10 is stamped to form the embossing required for the riveting process, thus forming a recess on the back surface 12 of the heat sink 10 at the position corresponding to the embossing. As a result, in the prior art, the effective area of ​​the heat dissipation surface of the semiconductor device 100, i.e., the back surface 12, is reduced, and therefore the heat dissipation characteristics of the semiconductor device 100 are sometimes reduced.

[0050] On the other hand, in the lead frame 1 of the embodiment, such as Figure 2B As shown, the heat sink 10 can be formed in such a way that the entire back surface 12 of the heat sink 10 is flat, thus improving the heat dissipation characteristics of the semiconductor device 100.

[0051] Alternatively, in another embodiment, a heat sink 10 can be fixed to the unit lead frame 20A by having multiple protrusions 22 respectively fitted into multiple first slots 13. Thus, since the number of fixing points between the heat sink 10 and the unit lead frame 20A increases, the heat sink 10 is stably fixed to the unit lead frame 20A.

[0052] Therefore, according to the embodiment, since the heat sink 10 is not easily detached from the unit lead frame 20A when manufacturing the semiconductor device 100, the semiconductor device 100 is manufactured stably.

[0053] In addition, Figures 1A to 2B In the example shown, two first slots 13 and two protrusions 22 are provided in each unit lead frame structure 1A, but the present disclosure is not limited to this example. For example, one first slot 13 and one protrusion 22 may be provided in each unit lead frame structure 1A, or three or more first slots 13 and three or more protrusions 22 may be formed in each unit lead frame structure 1A.

[0054] Additionally, the two first slots 13 can be located at the center X1 of the heat sink 10. Figure 1A The part is symmetrical about a reference point. As a result, since the heat sink 10 is fixed to the unit lead frame 20A without tilting, the semiconductor device 100 is manufactured stably.

[0055] Additionally, in the implementation method, such as Figure 2B As shown, the protrusion 22 may have a curved portion 22b. The curved portion 22b is, for example, located on the base end side of the protrusion 22 closer to the front end portion 22a, facing a main surface of the unit lead frame 20A. Figure 2B The middle section is bent in the manner of the back side 12).

[0056] Therefore, due to the front end portion 22a of the protrusion 22 and the lead wire 21 (see reference) Figure 2A Since they are not flush, the heat sink 10 and the lead wire 21 are not easily flush. That is, in the embodiment, as... Figure 2A As shown, even when the heat sink 10 and the lead wire 21 overlap when viewed from above, the heat sink 10 and the lead wire 21 are not easily in contact.

[0057] Therefore, according to the embodiment, since the heat sink 10 and the lead 21 are less prone to short circuits, a larger heat sink 10 can be formed. As a result, the heat dissipation characteristics of the semiconductor device 100 are improved.

[0058] Figure 3A This indicates the joint area between the heat sink 10 and the unit lead frame 20A in the embodiment. Figure 2A An enlarged top view of an example of the Y-section. Figure 3B yes Figure 3A The sectional view along the BB line is shown.

[0059] like Figure 3A as well as Figure 3B As shown, in one embodiment, two second grooves 14 may be formed on the heat sink 10, located adjacent to the first groove 13. The second grooves 14 may also be located in positions that sandwich the first groove 13 between each other.

[0060] Alternatively, the second groove 14 can be formed by stamping the area around the first groove 13 after the front end 22a of the protrusion 22 is housed in the first groove 13, so that it is V-shaped in cross-section.

[0061] Thus, through the forming process of the second groove 14, the side 22a1 of the front end 22a of the first groove 13 is pushed and housed from both sides, so the heat sink 10 is stably fixed to the unit lead frame 20A.

[0062] Therefore, according to the embodiment, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0063] Furthermore, in the embodiment, even when the width of the front end portion 22a in the protrusion 22 is smaller than the width of the first groove portion 13, the side surface 22a1 of the front end portion 22a can be pushed by the second groove portion 14 forming process after the front end portion 22a is housed in the first groove portion 13.

[0064] That is, in the embodiment, even if the width of the front end portion 22a in the protrusion 22 is smaller than the width of the first groove portion 13, the front end portion 22a can be fitted into the first groove portion 13 by forming a second groove portion 14 on the heat sink 10.

[0065] Therefore, according to the embodiment, since the front end portion 22a can be easily housed in the first groove portion 13, the manufacturing process of the lead frame 1 becomes simple.

[0066] Furthermore, in this embodiment, two second slots 14 may be formed on the heat sink 10 for each first slot 13. Thus, by pushing the side surface 22a1 of the front end portion 22a from both directions, the heat sink 10 is stably fixed to the unit lead frame 20A.

[0067] Therefore, according to the embodiment, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0068] Semiconductor Devices Next, refer to Figure 4A as well as Figure 4B The semiconductor device 100 using the lead frame 1 of the embodiment will be described. Figure 4A This is a top view showing an example of a semiconductor device 100 according to an embodiment. Figure 4B yes Figure 4A The sectional view along the CC line is shown. Furthermore, for ease of understanding, in... Figure 4A The dashed line in the middle represents 50g of sealing resin.

[0069] like Figure 4A as well as Figure 4B As shown, the semiconductor device 100 of the embodiment includes a portion of a unit lead frame structure 1A, a semiconductor element 30, a plurality of bonding wires 40, and a sealing resin 50.

[0070] As part of the unit lead frame structure 1A included in the semiconductor device 100, examples include the heat sink 10, a plurality of leads 21, a plurality of protrusions 22, etc.

[0071] Semiconductor element 30 is mounted on mounting surface 11 of heat sink 10. Multiple bonding wires 40 electrically connect an electrode (not shown) on the front side of semiconductor element 30 to a lead 21 corresponding to that electrode. Furthermore, the electrical connection between the electrode and the lead 21 is not limited to bonding wires 40; various conductive components such as conductive clips can also be used.

[0072] The sealing resin 50 is formed from, for example, epoxy resin, and is molded into a specified shape through a molding process or the like. The sealing resin 50 seals the semiconductor element 30, the bonding wire 40, the mounting surface 11 of the heat sink 10, and the portion of the lead 21 on the semiconductor element 30 side.

[0073] The portion of lead 21 opposite to the semiconductor element 30 side protrudes from the sealing resin 50 and functions as an external terminal (external lead) of the semiconductor device 100. Additionally, the back surface 12 of the heat sink 10 protrudes from the sealing resin 50 and is joined to heat dissipation components (not shown).

[0074] In addition, Figure 4A In the example shown, a portion of the protrusion 22 does not protrude from the sealing resin 50. However, in this disclosure, the portion of the protrusion 22 on the side opposite to the semiconductor element 30 can also be exposed in a manner that allows it to protrude from the sealing resin 50. Therefore, the exposed portion of the protrusion 22 can be used as a grounding terminal of the semiconductor device 100, etc.

[0075] Alternatively, in this case, the ground electrode (not shown) of the semiconductor element 30 may be connected to the heat sink 10 via a bonding wire 40 or a conductive clip.

[0076] Additionally, in the implementation method, such as Figure 3A as well as Figure 3B As shown, by forming a second groove 14 around the first groove 13, the sealing between the heat sink 10 and the protrusion 22 is improved. Therefore, according to the embodiment, when the exposed portion of the protrusion 22 is used as a ground terminal of the semiconductor device 100, the exposed portion of the protrusion 22 functions well as a terminal.

[0077] <Variation Example 1> Next, refer to Figures 5A to 8B The lead frame 1 of various modifications of the implementation method will be described. Figure 5A This is an enlarged cross-sectional view showing an example of the joint area between the heat sink 10 and the unit lead frame 20A in Modified Example 1 of the Embodiment, which is consistent with the Embodiment 1. Figure 3B The corresponding diagram.

[0078] like Figure 5A As shown, in the lead frame 1 of Modified Example 1, the protrusion 22 (see reference) Figure 4A The cross-sectional shape of the heat sink 10 fitted at the front end 22a is different from that in the embodiment described above. Specifically, in Variation 1, the heat sink 10 has a covering portion 15 that covers at least a portion of the upper surface 22a2 in the front end 22a.

[0079] The covering portion 15 can be formed, for example, by stamping a portion closer to the first groove portion 13 than the second groove portion 14 into a flat shape after the second groove portion 14 is formed by stamping.

[0080] Furthermore, in Modified Example 1, the heat sink 10 has a covering portion 15, which is supported from the upper surface 22a2 side by the front end 22a, so the heat sink 10 is stably fixed to the unit lead frame 20A.

[0081] Therefore, according to Modification 1, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0082] <Variations 2-4> Figure 5B This is an enlarged top view showing an example of the joint area between the heat sink 10 and the unit lead frame 20A in Modified Example 2 of the Embodiment 2, which is consistent with the Embodiment 2. Figure 3A The corresponding diagram.

[0083] like Figure 5B As shown, in the lead frame 1 of Modified Example 2, the arrangement of the second groove 14 differs from that in the embodiment described above. Specifically, in Modified Example 2, three second grooves 14 are formed around a first groove 13 on the heat sink 10.

[0084] Two of these second grooves 14 are located, for example, sandwiching the first groove 13 between them. Moreover, the other second groove 14 is located opposite the side of the front end portion 22a that is in contact with the heat sink 10 when viewed from above.

[0085] Thus, on the heat sink 10, three second grooves 14 are formed for each first groove 13, thereby pressing the side 22a1 of the front end 22a from three directions (see reference). Figure 3B Therefore, the heat sink 10 is stably fixed to the unit lead frame 20A.

[0086] Therefore, according to Modification 2, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0087] Furthermore, in Modification 2, even when the width of the front end portion 22a in the protrusion 22 is smaller than the width of the first groove portion 13, the front end portion 22a can still fit into the first groove portion 13 since three second groove portions 14 are formed on the heat sink 10.

[0088] Therefore, according to Modification 2, the front end portion 22a can be easily housed in the first groove portion 13, thus simplifying the manufacturing process of the lead frame 1.

[0089] Furthermore, in this disclosure, the number of second grooves 14 formed for each first groove 13 is not limited to two or three. For example, as Figure 6A As shown, a second groove 14 can also be formed on the heat sink 10 for each first groove 13. Figure 6A This is an enlarged top view showing an example of the joint area between the heat sink 10 and the unit lead frame 20A in a modified embodiment 3.

[0090] Therefore, it will also push the side 22a1 of the front end 22a from one direction (see reference). Figure 3B Therefore, the heat sink 10 is stably fixed to the unit lead frame 20A.

[0091] Therefore, according to Modification 3, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0092] Furthermore, in Modification 3, even when the width of the front end portion 22a in the protrusion 22 is smaller than the width of the first groove 13, the front end portion 22a can still fit into the first groove 13 since a second groove 14 is formed on the heat sink 10.

[0093] Therefore, according to Modification 3, the front end portion 22a can be easily housed in the first groove portion 13, thus simplifying the manufacturing process of the lead frame 1.

[0094] Figure 6B This is an enlarged top view showing another example of the joint area between the heat sink 10 and the unit lead frame 20A in Modified Example 3 of the embodiment. Figure 6B In the example, the two first slots 13 are arranged on the same side of the heat sink 10, and the two protrusions 22 are located at the positions corresponding to the two first slots 13 respectively.

[0095] Moreover, in Figure 6B In this example, a pair of second grooves 14 can be used to push the entire joint assembly from both sides of a joint assembly formed by two first grooves 13 and two protrusions 22. Thus, through the forming process of the second grooves 14, the entire joint assembly is pushed from both sides, thereby the heat sink 10 is stably fixed to the unit lead frame 20A.

[0096] Therefore, according to Figure 6B For example, in the manufacture of semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus ensuring stable manufacture of semiconductor device 100.

[0097] Additionally, in this disclosure, for example, Figure 7A As shown, a second groove 14 may not be formed on the heat sink 10 near the first groove 13 (see reference). Figure 3A ). Figure 7A This is an enlarged top view showing an example of the joint area between the heat sink 10 and the unit lead frame 20A in a variation of the embodiment 4.

[0098] Therefore, the width of the front end portion 22a in the protrusion 22 can also be slightly larger than the width of the first groove 13, so that the front end portion 22a can fit into the first groove 13.

[0099] Therefore, according to Modification 4, the area of ​​the part required for the joint is smaller compared to the case where the heat sink 10 is fixed to the lead frame body 20 by riveting.

[0100] <Variations 5-7> Figure 7B This is an enlarged top view showing an example of the joint area between the heat sink 10 and the unit lead frame 20A in Modified Example 5 of the Embodiment 1, which is consistent with the Embodiment 2. Figure 3A The corresponding diagram.

[0101] like Figure 7B As shown, in the lead frame 1 of Modified Example 5, the planar shapes of the first groove 13 and the front end portion 22a of the protrusion 22 are different from those in the embodiment described above. Specifically, in Modified Example 5, both the first groove 13 and the front end portion 22a of the protrusion 22 are formed into a generally T-shaped form when viewed from above.

[0102] Thus, in Modification 5, the first groove 13 includes a narrow groove 13a with a width W1 located at the end 11a of the mounting surface 11 and a wide groove 13b with a width W2 wider than the narrow groove 13a. Similarly, in Modification 5, the front end 22a of the protrusion 22 includes a first portion 22a3 with a width W1 located at the end 11a of the mounting surface 11 and a second portion 22a4 with a width W2 wider than the first portion 22a3.

[0103] Thus, in Modification 5, the first groove 13 includes a wide groove 13b, and the front end portion 22a of the protrusion 22 includes a second portion 22a4. Therefore, even when stress is applied to the heat sink 10 in a direction away from the protrusion 22, the heat sink 10 is not easily detached from the protrusion 22. Therefore, according to Modification 5, the semiconductor device 100 is manufactured stably.

[0104] Alternatively, in Modification 5, two second grooves 14 may be formed on the heat sink 10, located adjacent to the narrow groove 13a. The two second grooves 14 may also be located in a position that sandwiches the narrow groove 13a and its vicinity.

[0105] Thus, through the forming process of the second groove 14, the side surface 22a1 of the front end 22a of the first groove 13 is pushed and housed from both sides (see reference). Figure 3B Therefore, the heat sink 10 is stably fixed to the unit lead frame 20A.

[0106] Therefore, according to Modification 5, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0107] In the above explanation Figure 7B In the example shown, the planar shape of the first groove 13 and the front end portion 22a of the protrusion 22 is approximately T-shaped, but this disclosure is not limited to this example. Figure 8A This is an enlarged top view showing an example of the joint area between the heat sink 10 and the unit lead frame 20A in a modified embodiment 6.

[0108] like Figure 8A As shown, in modified example 6, the wide groove 13b of the first groove 13 and the second part 22a4 of the front end 22a of the protrusion 22 are both approximately circular when viewed from above.

[0109] Therefore, the first groove 13 also includes a wide groove 13b with a width of W2, and the protrusion 22 also includes a second portion 22a4 with a width of W2. Therefore, even when stress is applied to the heat sink 10 in a direction away from the protrusion 22, the heat sink 10 is not easily detached from the protrusion 22. Therefore, according to Modification 6, the semiconductor device 100 is manufactured stably.

[0110] Alternatively, in Modification 6, two second grooves 14 may be formed on the heat sink 10, located adjacent to the narrow groove 13a. Thus, through the forming process of the second grooves 14, the side surfaces 22a1 (refer to) of the front end portion 22a of the first groove 13 are pushed and housed from both sides. Figure 3B Therefore, the heat sink 10 is stably fixed to the unit lead frame 20A.

[0111] Therefore, according to Modification 6, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0112] Figure 8B This is an enlarged top view showing an example of the joint area between the heat sink 10 and the unit lead frame 20A in Modified Example 7 of the embodiment. Figure 8B As shown, in modified example 7, the wide groove 13b of the first groove 13 and the second part 22a4 of the front end 22a of the protrusion 22 are both roughly trapezoidal in shape when viewed from above.

[0113] Therefore, the first groove 13 also includes a wide groove 13b with a width of W2, and the protrusion 22 also includes a second portion 22a4 with a width of W2. Therefore, even when stress is applied to the heat sink 10 in a direction away from the protrusion 22, the heat sink 10 is not easily detached from the protrusion 22. Therefore, according to Modification 7, the semiconductor device 100 is stably manufactured.

[0114] Alternatively, in Modification 7, two second grooves 14 may be formed on the heat sink 10, located adjacent to the narrow groove 13a. Thus, through the forming process of the second grooves 14, the side surfaces 22a1 (see reference 13a1) of the front end portion 22a of the first groove 13 are pushed and housed from both sides. Figure 3B Therefore, the heat sink 10 is stably fixed to the unit lead frame 20A.

[0115] Therefore, according to Modification 7, when manufacturing the semiconductor device 100, the heat sink 10 is not easily detached from the unit lead frame 20A, thus the semiconductor device 100 is manufactured stably.

[0116] The various embodiments of this disclosure have been described above. However, this disclosure is not limited to the above embodiments, and various modifications can be made without departing from its spirit. For example, in the above embodiments, an example is shown in which two leads 21 are provided on a unit lead frame structure 1A. However, this disclosure is not limited to this example, and the number and configuration of leads 21 can be appropriately changed according to the specifications required by the semiconductor device 100.

[0117] Further effects and variations can be readily derived by those skilled in the art. Therefore, this disclosure is not limited to the specific details and representative embodiments shown and described above. Thus, various modifications can be made without departing from the spirit or scope of the general inventive concept as defined by the claims of this disclosure and its equivalents.

[0118] This application claims priority based on Japanese Patent Application No. 2024-59870, filed on April 3, 2024, and invokes all the contents set forth in the aforementioned application.

[0119] Explanation of reference numerals in the attached figures 1: Lead frame; 1A: Unit lead frame structure; 10: Heat sink; 11: Mounting surface; 11a: End; 13: First slot; 13a: Narrow slot; 13b: Wide slot; 14: Second slot; 20: Lead frame body; 20A: Unit lead frame; 21: Lead; 22: Protrusion; 22a: Front end; 22a3: First part; 22a4: Second part; 30: Semiconductor element; 40: Bonding wire; 50: Sealing resin; 100: Semiconductor device; W1, W2: Width.

Claims

1. A lead frame, comprising: A heat sink having a mounting surface for mounting semiconductor components; and A unit lead frame, which has leads, On the heat sink, a first groove is formed at the periphery of the mounting surface. The unit lead frame has a protrusion, the front end of which has a shape corresponding to the first slot. The heat sink is fixed to the unit lead frame by fitting the protrusion into the first groove.

2. The lead frame according to claim 1, characterized in that, A plurality of the first grooves are formed on the heat sink. The unit lead frame has a plurality of the protrusions. The heat sink is fixed to the unit lead frame by means of multiple protrusions that are respectively fitted into multiple first slots.

3. The lead frame according to claim 1 or 2, characterized in that, A second groove is formed on the heat sink, and the second groove is located adjacent to the first groove.

4. The lead frame according to claim 3, characterized in that, On the heat sink, a plurality of second slots are formed for each of the first slots.

5. The lead frame according to any one of claims 1 to 4, characterized in that, The first groove includes a narrow groove located at the end of the mounting surface and a second portion that is wider than the narrow groove.

6. A semiconductor device comprising: The lead frame according to any one of claims 1 to 5, and Semiconductor components mounted on the mounting surface.

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