Semiconductor device and method for manufacturing semiconductor device

Abstract

The semiconductor device of the present application more reliably prevents a deformed wire from contacting a frame in the semiconductor device. The semiconductor device includes a frame (10) having a first chip pad portion (11) on which a first semiconductor element (1) is mounted; a metal wire (20) connected to the first semiconductor element (1); and a sealing resin (30) that seals a portion of the frame (10), the first semiconductor element (1), and the metal wire (20). The first chip pad portion (11) has a first non-protruding portion (11a) that does not protrude from the first semiconductor element (1) in an area through which the metal wire (20) passes when viewed from above.

Description

Technical Field

[0001] This disclosure relates to a semiconductor device and a method for manufacturing a semiconductor device. Background Technology

[0002] For example, transfer-molded semiconductor devices are widely used in semiconductor devices, such as those for power control. Typically, a transfer-molded semiconductor device has the following structure: power control semiconductor elements such as MOSFETs (Metal-Oxide-Semiconductor Field-Effect Transistors) and IGBTs (Insulated-Gate Bipolar Transistors), and control semiconductor elements (control ICs) that control these semiconductor elements are electrically connected by wires, and sealed together with a frame using sealing resin. Furthermore, in its manufacturing process, the frame housing the power control semiconductor elements and the control semiconductor elements connected by wires is placed in a mold, and resin flows into the mold to form a sealing resin. Sometimes, the resin flowing into the mold can cause the wires to deform. If the deformed wires come into contact with the frame, a short circuit will occur, and the semiconductor device will malfunction.

[0003] Patent document 1 below proposes a technique that prevents the wire from contacting the frame even if the wire sags by providing a cut at the end of the frame located below the wire.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 11-126864 Summary of the Invention

[0007] The technical problem that the invention aims to solve

[0008] Furthermore, in the technology of Patent Document 1, the cut at the end of the frame does not reach the semiconductor element, and the upper surface of the frame is exposed between the semiconductor element and the cut. Therefore, a wire hanging from the upper surface of the semiconductor element may come into contact with the upper surface of the frame exposed between the semiconductor element and the cut.

[0009] This disclosure was made to solve the above-mentioned problems, and its purpose is to provide a semiconductor device that can more reliably prevent deformed wires from contacting the frame.

[0010] Technical means for solving technical problems

[0011] The semiconductor device disclosed herein includes: a frame having a first chip pad portion on which a first semiconductor element is mounted; a metal wire connected to the first semiconductor element; and a sealing resin sealing a portion of the frame, the first semiconductor element, and the metal wire, wherein the area through which the metal wire passes in a top view of the first chip pad portion has a portion that does not protrude from the first semiconductor element, namely a first non-protruding portion.

[0012] Invention Effects

[0013] According to the semiconductor device disclosed herein, it is possible to more reliably prevent deformed wires from contacting the frame. Attached Figure Description

[0014] Figure 1 This is a top view of the frame of the semiconductor device according to Embodiment 1.

[0015] Figure 2 This is a top view of the area near the first chip pad portion and the second chip pad portion in the semiconductor device according to Embodiment 1.

[0016] Figure 3 This is a cross-sectional view of the first chip pad portion and the vicinity of the second chip pad portion in the semiconductor device according to Embodiment 1.

[0017] Figure 4 This diagram illustrates the state of metal wire sagging that occurs in conventional semiconductor devices.

[0018] Figure 5 This is a diagram showing the state of metal wire sagging in the semiconductor device according to Embodiment 1.

[0019] Figure 6 This is a top view of the vicinity of the first chip pad portion and the second chip pad portion in a modified example of the semiconductor device according to Embodiment 1.

[0020] Figure 7 This is a cross-sectional view of the first chip pad portion and the second chip pad portion in a modified example of the semiconductor device according to Embodiment 1.

[0021] Figure 8 This is a cross-sectional view of the first chip pad portion and the second chip pad portion in the semiconductor device according to Embodiment 2.

[0022] Figure 9 This is a cross-sectional view of the first chip pad portion and the second chip pad portion in a modified example of the semiconductor device according to Embodiment 2.

[0023] Figure 10This is a cross-sectional view of the first chip pad portion and the second chip pad portion in a modified example of the semiconductor device according to Embodiment 2.

[0024] Figure 11 This is a diagram illustrating the manufacturing method of the semiconductor device according to Embodiment 3. Detailed Implementation

[0025] <Implementation Method 1>

[0026] Figure 1 This is a top view of the frame 10 of the semiconductor device according to Embodiment 1. Figure 2 This is a top view of the main parts of the semiconductor device according to Embodiment 1. Figure 1 An enlarged view of region A shown.

[0027] like Figure 1 and Figure 2 As shown, the semiconductor device includes a first semiconductor element 1 serving as a control IC, and a second semiconductor element 2, which is a power control semiconductor element (e.g., MOSFET, IGBT, etc.) controlled by the first semiconductor element 1. Figure 2 As shown, a first semiconductor element 1 is mounted on a first chip pad portion 11 of a frame 10, and a second semiconductor element 2 is mounted on a second chip pad portion 12 of the frame 10. Furthermore, the semiconductor device has multiple metal wires 20 connected to electrodes disposed on the upper surfaces of the first semiconductor element 1 and the second semiconductor element 2. A portion of the multiple metal wires 20 are connected between the first semiconductor element 1 and the second semiconductor element 2, and another portion is connected between the first semiconductor element 1 and the frame 10, or between the second semiconductor element 2 and other semiconductor elements (e.g., FWD (freewheeling diode)). Additionally, the second semiconductor element 2 also has electrodes on its bottom surface, and these electrodes are electrically connected to the frame 10 (second chip pad portion 12) via a bonding material such as solder.

[0028] A portion of the frame 10, including the first chip pad portion 11 and the second chip pad portion 12, the first semiconductor element 1, the second semiconductor element 2, and the metal wire 20 are... Figure 1 The sealing resin 30, indicated by dashed lines, is used for sealing. The portion of the frame 10 protruding from the sealing resin 30 becomes an external connection terminal. Additionally, Figure 1 The frame 10 is shown in its state before being sealed with sealing resin 30, with the portions serving as external connection terminals interconnected. After the sealing resin 30 is formed, the external connection terminals separate from each other.

[0029] Here, the sealing resin 30 is formed by placing a frame 10, on which the first semiconductor element 1, the second semiconductor element 2, and the metal wire 20 are mounted, inside a mold for molding the sealing resin 30, and injecting resin from the resin gate of the mold. Therefore, as... Figure 1 As shown, sometimes a resin gate mark 30a, representing the resin gate of the mold of the sealing resin 30, remains on the surface (usually the side) of the sealing resin 30. In this case, the flow direction R of the resin flowing into the mold from the resin gate during the formation of the sealing resin 30 (hereinafter referred to as "resin flow direction R") can be presumed to be a direction perpendicular to the side of the sealing resin 30 where the resin gate mark 30a exists. In addition, depending on how the sealing resin 30 is removed from the mold, the shape of the resin gate mark 30a may sometimes be a convex shape protruding from the surface of the sealing resin 30, and sometimes it may be a concave shape recessed from the surface of the sealing resin 30.

[0030] Furthermore, sometimes no resin gate mark 30a remains on the surface of the sealing resin 30. In this case, it is difficult to deduce the resin flow direction R from the appearance of the sealing resin 30. However, considering the filling properties of the resin within the mold, the position of the resin gate in the mold is generally configured so that the resin flow direction R is the long side direction of the sealing resin 30. Therefore, when no resin gate mark 30a remains on the surface of the sealing resin 30, if... Figure 1 The sealing resin 30 shown is rectangular when viewed from above, so it can be inferred that the resin inflow direction R is the direction of the long side of the sealing resin 30.

[0031] In the semiconductor device according to Embodiment 1, the first chip pad portion 11 of the frame 10, when viewed from above, has a portion that does not protrude from the first semiconductor element 1, namely a first non-protruding portion 11a, in the area through which the metal wire 20 passes. Similarly, the second chip pad portion 12 of the frame 10, when viewed from above, has a portion that does not protrude from the second semiconductor element 2, namely a second non-protruding portion 12a, in the area through which the metal wire 20 passes.

[0032] The first non-protruding portion 11a or the second non-protruding portion 12a does not need to be provided for all metal wires 20; it is sufficient to provide it for at least a portion of the metal wires 20. In this embodiment, the first non-protruding portion 11a is provided on the side parallel to the resin flow direction R of the first chip pad portion 11 (the side parallel to the long side direction of the sealing resin 30) when viewed from above, and the second non-protruding portion 12a is provided on the side parallel to the resin flow direction R of the second chip pad portion 12 when viewed from above. Since the metal wires 20 that cross the side parallel to the resin flow direction R are squeezed from the side by the resin and undergo greater deformation (the deformation of the metal wires 20 extending along the resin flow direction R is smaller), it is effective to provide the first non-protruding portion 11a or the second non-protruding portion 12a on the side parallel to the resin flow direction R.

[0033] Figure 3 This is a cross-sectional view of a first chip pad portion 11 including a first non-protruding portion 11a and a second chip pad portion 12 including a second non-protruding portion 12a. The end of the first chip pad portion 11 in the first non-protruding portion 11a does not protrude beyond the end of the first semiconductor element 1, and the end of the second chip pad portion 12 in the second non-protruding portion 12a does not protrude beyond the end of the second semiconductor element 2. Therefore, the upper surface of the frame 10 is not exposed in the first non-protruding portion 11a and the second non-protruding portion 12a.

[0034] Assuming that the end of the first chip pad portion 11 protrudes beyond the end of the first semiconductor element 1, and the end of the second chip pad portion 12 protrudes beyond the end of the second semiconductor element 2, as follows: Figure 4 As shown, due to the resin flow during the formation of the sealing resin 30, the metal wire 20 deforms, and when the metal wire 20 sags, it may come into contact with the frame 10. In contrast, in the semiconductor device of this embodiment, the end of the first chip pad portion 11 in the first non-protruding portion 11a does not protrude beyond the end of the first semiconductor element 1, and the end of the second chip pad portion 12 in the second non-protruding portion 12a does not protrude beyond the end of the second semiconductor element 2. Therefore, as... Figure 5 As shown, even if the metal wire 20 sags, it can prevent the metal wire 20 from contacting the frame 10.

[0035] Therefore, the semiconductor device according to Embodiment 1 can more reliably prevent the deformed metal wire 20 from contacting the frame 10.

[0036] In this embodiment, a structure is shown in which a first non-protrusion 11a is provided in the first chip pad portion 11, and a second non-protrusion 12a is provided in the second chip pad portion 12. That is, both the first chip pad portion 11 and the second chip pad portion 12 are provided with non-protrusions that do not protrude from the semiconductor element when viewed from above. However, for example, as Figure 3 As shown, when the second chip pad portion 12 is positioned lower than the first chip pad portion 11, contact with the metal wire 20 is more likely to occur in the first chip pad portion 11. Therefore, it is effective to provide a non-protruding portion in the first chip pad portion 11.

[0037] Therefore, as Figure 6 and Figure 7As shown, a structure can also be adopted in which a first non-protrusion 11a is provided in the first chip pad portion 11, and a second non-protrusion 12a is not provided in the second chip pad portion 12. That is, when the heights of the first chip pad portion 11 and the second chip pad portion 12 are different from each other, a non-protrusion can be provided only in the higher one (either the first chip pad portion 11 or the second chip pad portion 12). Since the strength of the frame 10 may be reduced in the areas where non-protrusions are provided, the strength of the frame 10 can be expected to be increased by reducing the number of areas where non-protrusions are provided.

[0038] Furthermore, for portions of the frame 10 that are at the same potential as the metal wire 20, such as those directly connected to the metal wire 20, no short circuit will occur even if they come into contact with the metal wire 20, which has been deformed by resin compression. Therefore, for portions of the frame 10 that are at the same potential as the metal wire 20, it is not necessary to provide non-protruding portions in the areas where the metal wire 20 passes.

[0039] <Implementation Method 2>

[0040] Figure 8 This is a top view of the main part of the semiconductor device according to Embodiment 2 (near the first chip pad portion 11 and the second chip pad portion 12).

[0041] In the semiconductor device according to Embodiment 2, the first non-protruding portion 11a and the second non-protruding portion 12a appear as cutouts when viewed from above. The other structures are the same as in Embodiment 1, so their descriptions are omitted.

[0042] By making the first non-protruding part 11a and the second non-protruding part 12a into a slit shape, the range of the non-protruding part in the frame 10 can be reduced, and the strength of the frame 10 can be expected to be improved compared with Embodiment 1.

[0043] From the perspective of improving the strength of the frame 10, the area where non-protruding portions are provided on the frame 10 is preferably narrower. Therefore, for example, Figure 9 As shown, non-protruding portions (first non-protruding portion 11a or second non-protruding portion 12a) can be locally provided in the area through which the metal wire 20 passes when viewed from above. Figure 9 In, with Figure 8 In comparison, the number of non-protruding parts increases, but because each non-protruding part is narrower, the overall range of non-protruding parts is larger than that of protruding parts. Figure 8 It should be narrow.

[0044] In addition, Figure 9In this configuration, the non-protruding portion (first non-protruding portion 11a or second non-protruding portion 12a) is arranged such that the metal conductor 20 passes through its central portion. However, when the non-protruding portion is located on the side of the chip pad portion (first chip pad portion 11 or second chip pad portion 12) parallel to the resin flow direction R, as... Figure 10 As shown, the distance L1 from the downstream end (the side away from the resin gate mark 30a) of the non-protruding portion in the resin flow direction R to the metal wire 20 is preferably longer than the distance L2 from the upstream end (the side closer to the resin gate mark 30a) of the non-protruding portion in the resin flow direction R to the metal wire 20. Since the metal wire 20 tends to deform and be pushed downstream in the resin flow direction R, making the distance L1 longer than the distance L2 can effectively prevent the metal wire 20 from contacting the frame 10.

[0045] The shapes of the slit-shaped first non-protruding portion 11a and the second non-protruding portion 12a are not limited to... Figures 8-10 The example shown (a shape with right angles at the corners) could also be a cone shape, for example.

[0046] <Implementation Method 3>

[0047] When manufacturing the semiconductor devices according to embodiments 1 and 2, if a mold capable of simultaneously molding multiple sealing resins 30 is used, multiple semiconductor devices can be formed simultaneously. In this case, as... Figure 11 As shown, multiple frames 10, each containing a first semiconductor element 1 and a metal wire 20, are arranged side-by-side within the mold. Then, by injecting resin through the mold's resin gate, multiple sealing resins 30 are simultaneously molded to seal each of the multiple frames 10, thus forming multiple semiconductor devices. However, since the sealing resins 30 are interconnected within the mold, after removing the simultaneously formed semiconductor devices from the mold, the sealing resins 30 can be cut to separate the semiconductor devices.

[0048] Here, during the resin injection process into the mold, the area near the resin gate (upstream of the resin flow direction R) is significantly affected by the resin flow, and the deformation of the metal wire 20 tends to increase. Conversely, the area away from the resin gate (downstream of the resin flow direction R) is less affected by the resin flow, and the deformation of the metal wire 20 tends to decrease. Therefore, in Embodiment 3, when multiple frames 10 are arranged within the mold, such as... Figure 11 As shown, a frame 10 with a smaller width of non-protruding parts (first non-protruding part 11a or second non-protruding part 12a) is provided at a position away from the resin gate, while a frame 10 with a larger width of non-protruding parts is provided at a position close to the resin gate. That is, within the mold, the width of the non-protruding parts of the frame 10 disposed away from the resin gate is set to be smaller than the width of the non-protruding parts of the frame 10 disposed near the resin gate.

[0049] According to the semiconductor device manufacturing method of Embodiment 3, a semiconductor device can be obtained in which the frame 10 has high strength (and a small width of the non-protrusion) while preventing the metal wire 20 from contacting the frame 10.

[0050] In addition, the various implementation methods can be freely combined, or the various implementation methods can be appropriately modified or omitted.

[0051] <Postscript>

[0052] The various methods disclosed herein are summarized and recorded below as appendices.

[0053] (Note 1) A semiconductor device, comprising: A frame having a first chip pad portion on which a first semiconductor element is mounted; A metal wire, which is connected to the first semiconductor element; and A sealing resin is used to seal a portion of the frame, the first semiconductor element, and the metal wires. When viewed from above, the area through which the metal wire passes in the first chip pad portion has a portion that does not protrude from the first semiconductor element, namely the first non-protruding portion.

[0054] (Note 2) The semiconductor device as described in Note 1, wherein, When the direction perpendicular to the edge where the sealing resin gate mark exists is taken as the resin inflow direction, The first non-protruding part is located on the side of the first chip pad portion that is parallel to the resin inflow direction when viewed from above.

[0055] (Note 3) The semiconductor device as described in Note 1, wherein, The first non-protruding part is located on the side of the first chip pad portion that is parallel to the long side of the sealing resin when viewed from above.

[0056] (Note 4) The semiconductor device as described in any one of Notes 1 to 3, wherein, The first non-protruding part appears as a cut when viewed from above.

[0057] (Note 5) The semiconductor device as described in Note 4, wherein, The first non-protruding portion, which is shaped like a cutout, is partially disposed in the area through which the metal wires of the first chip pad portion pass when viewed from above.

[0058] (Note 6) The semiconductor device as described in Note 4 or 5, wherein, When the direction perpendicular to the edge where the sealing resin gate mark exists is taken as the resin inflow direction, The first non-protruding portion, when viewed from above, is located on the side of the first chip pad portion parallel to the resin inflow direction. The distance from the downstream end of the first non-protruding portion in the resin inflow direction to the metal wire is longer than the distance from the upstream end of the first non-protruding portion in the resin inflow direction to the metal wire.

[0059] (Note 7) The semiconductor device as described in any one of Notes 1 to 6, wherein, The frame also has a second chip pad portion, which mounts a second semiconductor element connected to the first semiconductor element via the metal wire, and is positioned lower than the first chip pad portion.

[0060] (Note 8) The semiconductor device as described in Note 7, wherein, At least a portion of the area through which the metal wire passes when viewed from above has a portion that does not protrude from the second semiconductor element, namely a second non-protruding portion.

[0061] (Appendix 9) A method for manufacturing a semiconductor device, as described in any one of Appendices 4 to 6, comprising: The process of arranging multiple frames, each containing the first semiconductor element and the metal wire, side by side within a mold; The process of forming the sealing resin by injecting resin from the resin gate of the mold; and The process of cutting the sealing resin to cut out multiple semiconductor devices. The width of the first non-protruding portion of the frame located away from the resin gate of the mold is smaller than the width of the first non-protruding portion of the frame located near the resin gate.

[0062] Label Explanation

[0063] 1 First semiconductor element, 2 Second semiconductor element, 10 Frame, 11 First chip pad portion, 11a First non-protruding portion, 12 Second chip pad portion, 12a Second non-protruding portion, 20 Metal wire, 30 Sealing resin, 30a Resin gate mark, R Resin flow direction.

Claims

1. A semiconductor device, characterized in that, include: A frame having a first chip pad portion on which a first semiconductor element is mounted; A metal wire, which is connected to the first semiconductor element; as well as A sealing resin is used to seal a portion of the frame, the first semiconductor element, and the metal wires. When viewed from above, the area through which the metal wire passes in the first chip pad portion has a portion that does not protrude from the first semiconductor element, namely the first non-protruding portion.

2. The semiconductor device as claimed in claim 1, characterized in that, When the direction perpendicular to the edge where the sealing resin gate mark exists is taken as the resin inflow direction, The first non-protruding part is located on the side of the first chip pad portion that is parallel to the resin inflow direction when viewed from above.

3. The semiconductor device as claimed in claim 1, characterized in that, The first non-protruding part is located on the side of the first chip pad portion that is parallel to the long side of the sealing resin when viewed from above.

4. The semiconductor device according to any one of claims 1 to 3, characterized in that, The first non-protruding part appears as a cut when viewed from above.

5. The semiconductor device as claimed in claim 4, characterized in that, The first non-protruding portion, which is shaped like a cutout, is partially disposed in the area through which the metal wires of the first chip pad portion pass when viewed from above.

6. The semiconductor device as claimed in claim 4 or 5, characterized in that, When the direction perpendicular to the edge where the sealing resin gate mark exists is taken as the resin inflow direction, The first non-protruding portion, when viewed from above, is located on the side of the first chip pad portion parallel to the resin inflow direction. The distance from the downstream end of the first non-protruding portion in the resin inflow direction to the metal wire is longer than the distance from the upstream end of the first non-protruding portion in the resin inflow direction to the metal wire.

7. The semiconductor device according to any one of claims 1 to 6, characterized in that, The frame also has a second chip pad portion, which mounts a second semiconductor element connected to the first semiconductor element via the metal wire, and is positioned lower than the first chip pad portion.

8. The semiconductor device as claimed in claim 7, characterized in that, At least a portion of the area through which the metal wire passes when viewed from above has a portion that does not protrude from the second semiconductor element, namely a second non-protruding portion.

9. A method for manufacturing a semiconductor device, as described in any one of claims 4 to 6, characterized in that, include: The process of arranging multiple frames, each containing the first semiconductor element and the metal wire, side by side within a mold; The process of forming the sealing resin by injecting resin from the resin gate of the mold; as well as The process of cutting the sealing resin to cut out multiple semiconductor devices. The width of the first non-protruding portion of the frame located away from the resin gate of the mold is smaller than the width of the first non-protruding portion of the frame located near the resin gate.

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