Semiconductor equipment

Abstract

To provide a semiconductor device having no bonding defect.SOLUTION: A semiconductor device includes a metal frame disposed apart from a semiconductor chip, and a metal connector which is connected to the semiconductor chip through a first bonding material and connected to the metal frame through a second bonding material. The metal frame includes an arrangement surface on which the second bonding material is arranged, and an inclined surface which is adjacent to the arrangement surface and inclined at a predetermined angle with respect to the arrangement surface. The metal connector includes a first part which is connected to the first bonding material and serves as one end portion, a second part which is integrally connected to the first part and formed to rise toward the metal frame, a third part which is integrally connected to the second part and serves as the other end portion, a connecting surface which is formed on the third part and connected to the second bonding material, the other end side surface which is adjacent to the connecting surface formed on the third part and faces the inclined surface of the metal frame, and a notch which is opened the other end side surface and penetrates through the third part in a thickness direction.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] Embodiments of the present invention relate to semiconductor devices.

Background Art

[0002] Conventionally, in a semiconductor package manufactured by joining a Si semiconductor chip or the like to various connectors including a lead frame formed of copper or the like and a gate connector using a bonding material such as solder and then molding and sealing with resin, a reflow furnace for heating and adhering the solder is used in the joining process.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When joining, for example, a gate connector to a semiconductor chip in a reflow furnace, surface tension of solder melted and flowing around the side surface of the end portion on the lead frame connection side of the gate connector may be generated between the side surface and the inclined surface of the lead frame facing the side surface. Then, when the surface tension acts on the gate connector, the lead frame connection side of the gate connector may be pulled downward. As a result, a phenomenon in which the side of the gate connector connected to the semiconductor chip floats up, a so-called Manhattan phenomenon, may occur, which may cause a poor connection between the gate connector and the semiconductor chip.

[0005] Therefore, there is a problem of providing a semiconductor device that does not have a poor connection due to the Manhattan phenomenon of the gate connector.

Means for Solving the Problems

[0006] The semiconductor device of the embodiment comprises a semiconductor chip having electrodes, a first bonding material provided on the electrodes of the semiconductor chip, a metal frame disposed spaced apart from the semiconductor chip, a second bonding material provided on the metal frame, and a metal connector connected to the semiconductor chip via the first bonding material and connected to the metal frame via the second bonding material, wherein the metal frame comprises a mounting surface on which the second bonding material is disposed, and an inclined surface adjacent to the mounting surface and inclined at a predetermined angle with respect to the mounting surface, and the metal The connector comprises a first portion connected to the first joining material and forming one end; a second portion integrally connected to the first portion and formed to rise toward the metal frame; a third portion integrally connected to the second portion and forming the other end; a connecting surface formed in the third portion and connected to the second joining material; a side surface formed in the third portion adjacent to the connecting surface and facing the inclined surface of the metal frame; and a notch formed in the third portion that opens into the side surface and penetrates through the third portion in the thickness direction. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a perspective view showing the semiconductor device of this embodiment. [Figure 2] Figure 2 is a cross-sectional view showing the semiconductor device of this embodiment. [Figure 3] Figure 3 is a plan view showing the semiconductor device of this embodiment. [Figure 4] Figure 4 is a plan view illustrating the semicircular notch formed in the third part of the metal connector. [Figure 5] Figure 5 is a plan view illustrating the V-shaped notch formed in the third part of the metal connector. [Figure 6] Figure 6 is a cross-sectional view illustrating a poor connection between a metal connector and a semiconductor chip due to the Manhattan effect when the metal connector does not have a notch. [Modes for carrying out the invention]

[0008] The semiconductor device 1 of this embodiment, as outlined with reference to Figures 1 to 3, comprises a first lead frame 10, a second lead frame 12, a metal frame 30 which is a third lead frame, a source connector 40 which is a first conductive member, a metal connector 5 which is a second conductive member, a semiconductor chip 14 having multiple electrodes, and a sealing material 19 which protects the semiconductor chip 14. In Figures 1 to 3, the sealing material 19 is shown by a dashed line to make the internal structure of the semiconductor device 1 easier to understand.

[0009] The following describes each part of the semiconductor device 1 in detail. In the following description, a Cartesian coordinate system of X, Y, and Z axes is used. The X-axis direction includes the +X direction and the -X direction. The Y-axis direction includes the +Y direction and the -Y direction. The Z-axis direction includes the +Z direction and the -Z direction. As shown in Figures 1 to 3, the direction from the main body 101 of the first lead frame 10 toward the semiconductor chip 14 is defined as the upward direction (+Z direction). The opposite direction of the upward direction is defined as the downward direction (-Z direction). In the X-Y axis plane (horizontal plane), the direction from the metal connector 5 toward the metal frame 30 is defined as the +X direction, and the opposite direction of the +X direction is defined as the -X direction. The direction from the second lead frame 12 toward the metal frame 30 is defined as the +Y direction, and the opposite direction of the +Y direction is defined as the -Y direction.

[0010] The planar rectangular semiconductor chip 14 shown in Figures 1 to 3 is a MOSFET (Metal-Oxide-Semiconductor Field Effect Transistor) with silicon as the base material in this embodiment, but is not limited to this. That is, the semiconductor chip 14 may be, for example, a vertical IGBT (Insulated Gate Bipolar Transistor), a vertical diode, or another semiconductor chip. Also, the semiconductor chip 14 may use a compound other than silicon, such as SiC or GaN, as the base material. The semiconductor chip 14 is arranged on the main body portion 101 of the first lead frame 10, for example, sandwiching a copper block 102.

[0011] The first lead frame 10 is made of a conductive material such as copper and comprises, for example, a main body portion 101 which is a die pad, a copper block 102 disposed on the main body portion 101, and a protruding portion 104 that protrudes from the main body portion 101 in the +X direction in a plan view. The copper block 102 plays a role in adjusting the overall thickness of the first lead frame 10 in the Z-axis direction. Therefore, the first lead frame 10 does not necessarily have to include the copper block 102.

[0012] The main body 101 is plate-shaped, and for example, the length of the copper block 102 in the X-axis direction and the length in the Y-axis direction are set to be smaller than the length of the main body 101 in the X-axis direction and the length in the Y-axis direction. Also, the thickness of the copper block 102 in the Z-axis direction is set to be thicker than the thickness of the main body 101. For example, the upper and lower surfaces of the main body 101 are parallel to the horizontal plane (X-axis and Y-axis plane). As shown in Figure 2, the copper block 102 is connected to the upper surface of the main body 101 by a joining member 101c such as solder.

[0013] As shown in Figures 1 to 3, the protrusion 104 protrudes from the main body 101 in the +X direction and is located between the second lead frame 12 and the metal frame 30 in the Y-axis direction. The protrusion 104 has, for example, a first extension 104a and a second extension 104b.

[0014] As shown in Figure 2, the first extension portion 104a is connected to the main body portion 101. Also, as shown in Figure 1, the first extension portion 104a extends along a direction inclined with respect to the Z-axis and X-axis directions, so as it moves upward in the +X direction. The second extension portion 104b is connected to the first extension portion 104a and extends from the first extension portion 104a along the +X direction. For example, the upper surface of the second extension portion 104b is parallel to the horizontal plane. Note that the first lead frame 10 does not necessarily have to have the protruding portion 104.

[0015] The first lead frame 10 includes, for example, a second projection 106 extending in the -X direction from the main body 101. For example, the second projection 106 has a larger width in the Y-axis direction than the main body 101 and extends substantially parallel to the horizontal plane from the -X side end of the main body 101. Note that the first lead frame 10 does not necessarily have to include the second projection 106.

[0016] As shown in Figure 2, a conductive bonding member 102b, such as solder, is provided between the lower surface 14b of the semiconductor chip 14 and the upper surface 102a of the copper block 102, and the semiconductor chip 14 and the copper block 102 are joined by the bonding member 102b. The semiconductor chip 14 is equipped with multiple electrodes, for example, a first electrode 141, a second electrode 142, and a third electrode 143.

[0017] The first electrode 141 shown in Figures 1 and 2 is provided on the upper surface 14a of the semiconductor chip 14. In this embodiment, the first electrode 141 corresponds to the gate electrode. The second electrode 142 shown in Figures 1 and 2 is provided on the upper surface 14a of the semiconductor chip 14, for example, over a larger area than the first electrode 141. In this embodiment, the second electrode 142 corresponds to the source electrode. As shown in Figure 1, the first electrode 141 and the second electrode 142 are arranged spaced apart in the X-axis and Y-axis planes so as not to come into contact with each other.

[0018] As shown in Figure 2, the third electrode 143 is provided on the lower surface 14b of the semiconductor chip 14. The third electrode 143 extends, for example, over substantially the entire area of ​​the lower surface 14b. In this embodiment, the third electrode 143 corresponds to the drain electrode. The third electrode 143 is electrically connected to the first lead frame 10 via a bonding member 102b.

[0019] The second lead frame 12 is made of a conductive material such as copper. As shown in Figures 1 and 3, the second lead frame 12 is spaced apart from the first lead frame 10 in the X-axis direction. In this embodiment, the second lead frame 12 has a flat portion 121, an inclined portion 125, a first extended portion 122, a second extended portion 123, and a third extended portion 124.

[0020] As shown in FIG. 1, the flat plate portion 121 is located, for example, above the upper surface 14a of the semiconductor chip 14. Also, as shown in FIG. 3, in a plan view, the flat plate portion 121 is spaced apart from the main body portion 101 in the +X direction. The upper surface 121a of the flat plate portion 121 is, for example, parallel to the X-axis Y-axis plane (horizontal plane).

[0021] The first extension portion 122 is connected to the flat plate portion 121 via the inclined portion 125 and extends along the +X direction. The first extension portion 122 is located above the flat plate portion l21. Therefore, the inclined portion 125 extends obliquely upward toward the +X direction side. The second extension portion 123 is connected to the first extension portion 122. The second extension portion 123 extends along a direction inclined with respect to the X-axis direction and the Z-axis direction so as to go downward as it goes in the +X direction. The third extension portion 124 is connected to the second extension portion 123 and extends along the +X direction.

[0022] The metal frame 30 is made of a conductive material such as copper. As shown in FIGS. 1 to 3, the metal frame 30 is spaced apart from the first lead frame 10 and the semiconductor chip 14. Also, the second lead frame 12 and the metal frame 30 are arranged to be spaced apart from each other in the Y-axis direction. In the present embodiment, the metal frame 30 has a flat plate portion 301, an inclined portion 305, a first extension portion 302, a second extension portion 303, and a third extension portion 304. Further, the flat plate portion 301, the inclined portion 305, and the first extension portion 302 of the metal frame 30 are positioned above the outer periphery of the semiconductor chip 14 (on the +X direction side).

[0023] As shown in Figures 1 and 2, the flat plate portion 301 is located above the upper surface 14a of the semiconductor chip 14. In a plan view, the flat plate portion 301 is spaced apart from the main body portion 101 in the +X direction. For example, the upper surface of the flat plate portion 301 is parallel to the horizontal plane. As shown in Figures 2 and 3, the upper surface of the flat plate portion 301 is the mounting surface 301a on which the second bonding material 301d is disposed. For example, in the Z-axis direction, the mounting surface 301a is located at approximately the same height as the upper surface 121a of the flat plate portion 121 of the second lead frame 12.

[0024] As shown in Figures 1 and 2, the inclined portion 305 is connected to the flat plate portion 301 and extends diagonally upward in the +X direction from the flat plate portion 301. The upper surface of the inclined portion 305 is adjacent to the mounting surface 301a and is inclined at a predetermined angle with respect to the mounting surface 301a, forming an inclined surface 305a.

[0025] As shown in Figure 2, for example, the inclined portion 305 is inclined at a 45-degree angle from the mounting surface 301a which is parallel to the horizontal plane (X-axis and Y-axis plane), but the inclination angle is not limited to this example. The inclined surface 305a of the inclined portion 305 faces the other end side (+X direction side) of the metal connector 5 in the X-axis direction.

[0026] The first extension 302 is connected to the inclined section 305 and extends parallel to the +X direction. The second extension 303 is connected to the first extension 302. The second extension 303 extends inclined with respect to the X-axis and Z-axis directions, becoming downward as it moves toward the +X direction. The third extension 304 is connected to the second extension 303 and extends along the +X direction.

[0027] The source connector 40 shown in Figure 1 electrically connects the second electrode 142, which is the source electrode of the semiconductor chip 14, to the second lead frame 12. The source connector 40 is made of a conductive material such as copper. The source connector 40 has a plate-shaped first portion 41, a second portion 42 that rises from the first portion 41 in the +Z direction, and a plate-shaped third portion 43. In the illustrated example, the source connector 40 is formed to be larger than the metal connector 5, which is the gate connector.

[0028] For example, the first portion 41, which is formed in the shape of a roughly rectangular plate in plan view, is placed on the second electrode 142. As shown in Figure 2, a conductive bonding member 403, such as solder, is placed between the lower surface of the first portion 41 and the second electrode 142, and the first portion 41 and the second electrode 142 are joined by the bonding member 403.

[0029] The second portion 42 rises from the +X-direction end of the first portion 41 in the +Z direction for a predetermined length, and then extends in the +X direction. The third portion 43, which is integrally connected to the second portion 42, is formed to have a smaller length (width) in the Y-axis direction compared to the first portion 41 and the second portion 42. The third portion 43 is provided on the flat plate portion 121 of the second lead frame 12. As shown in Figure 2, a conductive joining member 435, such as solder, is placed between the lower surface of the third portion 43 and the upper surface 121a of the flat plate portion 121, and the third portion 43 and the flat plate portion 121 are joined by the joining member 435.

[0030] As shown in Figures 1 to 3, the metal connector 5 electrically connects the first electrode 141 on the semiconductor chip 14 to the metal frame 30. The metal connector 5 is made of a conductive material such as copper. The metal connector 5, which is the second conductive member, and the source connector 40, which is the first conductive member, are spaced apart in the horizontal direction.

[0031] In this embodiment, the -X direction side of the metal connector 5 is one end, and the +X direction side is the other end, which is opposite to the first end. The metal connector 5 has, for example, a first portion 51 which is one end that connects to the semiconductor chip 14, a second portion 52 which is integrally connected to the first portion 51 and extends upward toward the metal frame 30, and a third portion 53 which is the other end that connects to the metal frame 30.

[0032] The first portion 51 is positioned on the first electrode 141. A first bonding material 515, such as solder, is placed between the first portion 51 and the first electrode 141, and the first portion 51 and the first electrode 141 are joined by the first bonding material 515. The first portion 51 is formed, for example, in a rectangular shape in plan view.

[0033] The second part 52 is integrally connected to the first part 51 and extends so as to be inclined with respect to the Z-axis and X-axis directions, with the direction moving upward as it moves toward the +X direction. For example, the direction in which the inclined surface 305a of the metal frame 30 and the other end side surface 53b of the metal connector 5 face each other (X-axis direction) and the direction perpendicular to the thickness direction of the third part 53 (Z-axis direction) (Y-axis direction) is defined as the width direction of the metal connector 5. In this embodiment, the length (width) of the first part 51 and the second part 52 in the Y-axis direction (width direction) is set to be approximately the same.

[0034] As shown in Figures 1 and 2, the third portion 53, located above the first portion 51, is provided on the flat plate portion 301 of the metal frame 30. The lower surface of the third portion 53 shown in Figure 2 is the connecting surface 53a. A second joining material 301d, such as solder, is placed between the connecting surface 53a and the mounting surface 301a of the flat plate portion 301, and the third portion 53 and the flat plate portion 301 are joined by the second joining material 301d.

[0035] The shape of the third part 53 of the metal connector 5 is plate-like. The third part 53 has a shape in which a trapezoidal plate extending in the +X direction while gradually increasing in width in the Y-axis direction (width direction) from the second part 52 and a substantially rectangular plate with a constant width in the Y-axis direction are integrated flush with each other. The width of the third part 53 in the Y-axis direction is set to be several times larger than the width of the first part 51 and the second part 52 in the Y-axis direction. Furthermore, in this embodiment, the weight of the third part 53 is greater than the weight of the first part 51.

[0036] In the examples shown in Figures 1 and 3, the connection point of the second part 52 to the third part 53 is offset to the -Y direction from the midpoint of the third part 53 in the Y-axis direction, but the connection point may coincide with the midpoint of the third part 53 in the Y-axis direction.

[0037] The side of the third portion 53 shown in Figures 2 and 3 on the +X direction side is defined as the other end side 53b. The other end side 53b adjacent to the connecting surface 53a shown in Figure 2 faces the inclined surface 305a of the inclined portion 305 of the metal frame 30 in the X-axis direction, with a predetermined gap between them.

[0038] The metal connector 5 of the semiconductor device 1 in this embodiment is formed to open from the other end side surface 53b of the third portion 53 toward, for example, the first portion 51, and includes a notch 542 that penetrates in the thickness direction (Z-axis direction) of the metal connector 5.

[0039] As shown in Figures 1 and 2, the notches 542 are, for example, rectangular in shape when the metal connector 5 is viewed from above, and two of them are formed side by side in the Y-axis direction in the region on the +X direction side of the third portion 53. The two notches 542 give the third portion 53 three protrusions 533.

[0040] The other end surfaces 53b of each of the protrusions 533 on the +X direction side shown in Figure 1 are, for example, in the same position in the X-axis direction. However, the positions of the other end surfaces 53b of the three protrusions 533 in the X-axis direction may be different. For example, the widths of the two notches 542 in the Y-axis direction are the same, and the spacing of the three protrusions 533 formed by the two notches 542 in the Y-axis direction is, for example, equal. However, the widths of the two notches 542 may be different. Also, the number of notches 542 formed in the third part 53 is not limited to two, but may be one or three or more. In addition, the length L1 in the X-axis direction of the two notches 542 of the third part 53 is the same in the examples shown in Figures 2 and 3, but the lengths of the two notches 542 in the X-axis direction may be different.

[0041] In the semiconductor device 1 of this embodiment, for example, in the direction (X-axis direction) where the inclined surface 305a of the metal frame 30 and the other end side surface 53b of the metal connector 5 face each other, the length L1 of the two notches 542 of the metal connector 5 is set to be longer than the distance L2 (maximum distance L2) between the inclined surface 305a of the metal frame 30 and the other end side surface 53b of the metal connector 5.

[0042] The notches formed in the third portion 53 are not limited to the rectangular notches 542 shown in Figures 1 and 3. As shown in Figure 4, instead of the rectangular notches 542, two semicircular notches 543 may be formed in the third portion 53. For example, the semicircular notches 543 are formed in the third portion 53 such that the center of the semicircular notch 543 is at the same position as the other end surface 53b of the third portion 53 in the X-axis direction. There may be one or more notches 543, and they may be semi-elliptical notches instead of semicircular notches. In this case, the major axis of the semi-elliptical notch may be parallel to the X-axis direction, or the minor axis may be parallel to the X-axis direction.

[0043] For example, in the X-axis direction, the length L3 of the two semicircular notches 543 of the metal connector 5 is the radius of the notches 543. The length L3 of the two notches 543 is set to be longer than, for example, the maximum distance L2 between the inclined surface 305a of the metal frame 30 and the other end side surface 53b of the metal connector 5.

[0044] For example, as shown in Figure 5, the third portion 53 of the metal connector 5 may have two V-shaped notches 544 instead of the rectangular notch 542 shown in Figure 1. There may be one or more notches 544. For example, in the X-axis direction shown in Figure 5, the length L4 of the two notches 544 of the metal connector 5, that is, the length L4 from the other end side surface 53b to the tip of the V-shape of the notch 544, is set to be longer than, for example, the maximum distance L2 between the inclined surface 305a of the metal frame 30 and the other end side surface 53b of the metal connector 5.

[0045] As shown in Figures 1 to 3, the sealing material 19 is formed in a substantially rectangular parallelepiped shape in this embodiment. However, the shape of the sealing material 19 is not limited to this example. The sealing material 19 seals the joint between the first lead frame 10 and the semiconductor chip 14, the joint between the first electrode 141 and the metal connector 5, the joint between the metal connector 5 and the metal frame 30, the joint between the second electrode 142 and the source connector 40, and the joint between the source connector 40 and the second lead frame 12. Specifically, the sealing material 19 covers the upper and side surfaces of the main body portion 101 of the first lead frame 10, the upper surface 102a and side surfaces of the copper block 102, and a portion of the protruding portion 104 from the first extended portion 104a to the second extended portion 104b. The sealing material 19 also covers a portion of the flat plate portion 121 to the first extended portion 122 of the second lead frame 12. Furthermore, the sealing material 19 covers a portion of the first extended portion 302 from the flat plate portion 301 of the metal frame 30.

[0046] The sealing material 19 exposes a portion of the first lead frame 10, a portion of the second lead frame 12, and a portion of the metal frame 30. Specifically, the sealing material 19 exposes the lower surface of the main body portion 101 of the first lead frame 10, the other portion of the second extension portion 104b of the protrusion portion 104, and the second protrusion portion 106. The sealing material 19 also exposes the other portion of the first extension portion 122, the second extension portion 123, and the third extension portion 124 of the second lead frame 12. Furthermore, the sealing material 19 exposes the other portion of the first extension portion 302, the second extension portion 303, and the third extension portion 304 of the metal frame 30.

[0047] When the semiconductor device 1 is in use, the lower surface of the main body portion 101 of the first lead frame 10, the second protrusion 106 of the first lead frame 10, the third extension portion 124 of the second lead frame 12, and the third extension portion 304 of the metal frame 30 are electrically connected to the external wiring. However, the portions of the first lead frame 10, the second lead frame 12, and the metal frame 30 that are exposed from the sealing material 19 are not limited to the above example.

[0048] Next, the process for manufacturing the semiconductor device 1 according to this embodiment will be briefly described. First, the first lead frame 10 shown in Figures 1 to 3 is prepared. Note that the main body 101 and the copper block 102 of the first lead frame 10 are pre-integrated. First, the semiconductor chip 14 is placed on the bonding member 102b of the copper block 102. At this time, the semiconductor chip 14 is positioned so that the third electrode 143 faces the bonding member 102b on the copper block 102. Therefore, the second electrode 142 and the first electrode 141 of the semiconductor chip 14 are exposed on the upper surface 14a of the semiconductor chip 14.

[0049] Next, the bonding member 403 before reflow is placed on the second electrode 142 of the semiconductor chip 14. The first bonding material 515 before reflow is placed on the first electrode 141 of the semiconductor chip 14. The bonding member 435 before reflow is placed on the upper surface 121a of the flat plate portion 121 of the second lead frame 12. The second bonding material 301d before reflow is placed on the mounting surface 301a, which is the upper surface of the flat plate portion 301 of the metal frame 30. The order in which the above bonding materials are placed is not particularly limited.

[0050] Next, the source connector 40 is placed on the joining member 403 and the joining member 435. The first part 51 of the metal connector 5, which is a gate connector, is placed on the first joining member 515, and the third part 53 of the metal connector 5 is placed on the second joining member 301d. As a result, the connecting surface 53a of the third part 53 and the second joining member 301d are in surface contact. In addition, a predetermined gap is formed between the other end side surface 53b of the third part 53 and the inclined surface 305a of the inclined portion 305 of the metal frame 30, and in this embodiment, the three other end side surfaces 53b and the inclined surfaces 305a face each other in the X-axis direction. For example, the shape of the second joining member 301d is cut in advance to match the shape of the notch 542 of the third part 53. That is, when the third part 53 is viewed from above, the second joining member 301d is not exposed in the two notches 542.

[0051] Next, the first lead frame 10, the second lead frame 12, the metal frame 30, the source connector 40, the metal connector 5, the semiconductor chip 14, and the intermediate body including the first bonding material 515 and the second bonding material 301d described earlier are placed in a reflow oven (not shown). The intermediate body is then heated to melt the bonding member 102b, the first bonding material 515, the second bonding material 301d, the bonding member 403, and the bonding member 435 shown in Figure 2.

[0052] Subsequently, the joining member 102b, the first joining material 515, the second joining material 301d, the joining member 403, and the joining member 435 are cooled and solidified. This joins the first lead frame 10 and the semiconductor chip 14. In addition, the first portion 41 of the source connector 40 is joined to the second electrode 142 of the semiconductor chip 14, and the third portion 43 is joined to the flat plate portion 121 of the second lead frame 12.

[0053] For example, consider the case where the metal connector 5 of the semiconductor device 1 does not have the notch 542 shown in Figures 1 to 3. In the metal connector 5A shown in Figure 6, which does not have the notch 542, a bonding failure due to the Manhattan effect may occur after the cooling and solidification of the first bonding material 515 and the second bonding material 301d. Note that in Figure 6, the source connector 40 and the protrusion 104 are omitted, and a part of the metal connector 5A without the notch 542 as shown in Figures 1 to 3 and a part of the metal frame 30 are shown in an enlarged view. Furthermore, the other end side surface on the +X direction side of the third portion 53 of the metal connector 5A without the notch 542 is referred to as the other end side surface 53c. That is, the other end side surface 53c of the third portion 53 of the metal connector 5 shown in Figure 6 is continuous from end to end in the Y-axis direction without interruption.

[0054] During the reflow process, the first bonding material 515, which is solder, and the second bonding material 301d, which is solder, melt together. As a result, the liquefied second bonding material 301d on the placement surface 301a may wrap around to the other end side surface 53c of the third portion 53 of the metal connector 5A shown in Figure 6, which does not have a notch 542, as shown in Figure 6. Consequently, the gap between the other end side surface 53c, which is continuous without interruption in the Y-axis direction, and the inclined surface 305a of the metal frame 30 becomes an elongated gap extending in the Y-axis direction. The liquefied second bonding material 301d that has wrapped around to the other end side surface 53c is drawn downwards into this elongated gap. Surface tension is then generated between the other end side surface 53c and the inclined surface 305a, and this surface tension may pull the metal connector 5A diagonally downwards (in the direction of arrow R1) towards the inclined surface 305a. Then, the first part 51 may be lifted up, causing the first part 51 to separate from the first bonding material 515, a phenomenon known as the Manhattan effect, which can result in a poor connection between the metal connector 5A and the semiconductor chip 14.

[0055] Furthermore, the metal connector 5A of the semiconductor device 1 has a third portion 53 on the side that connects to the metal frame 30 that is wider than the width of the first portion 51 in the Y-axis direction, and the weight of the third portion 53 is greater than the weight of the first portion 51, so the center of gravity of the metal connector 5A is biased towards the third portion 53 side. Consequently, the first portion 51 side is more easily lifted by the pulling of the third portion 53 due to the surface tension, making poor connections between the metal connector 5A and the semiconductor chip 14, as shown in Figure 6, which does not have a notch 542, more likely to occur.

[0056] Therefore, if a notch 542 is not formed, as in the metal connector 5A, the semiconductor device 1 after the cooling and solidification of the molten first bonding material 515 and the second bonding material 301d may have a poor bond between the semiconductor chip 14 and the metal connector 5A as shown in Figure 6 due to the Manhattan effect.

[0057] The metal connector 5 of the semiconductor device 1 in this embodiment, as shown in Figures 1 to 3, is formed to open from the other end side surface 53b of the third portion 53 toward the first portion 51, and has, for example, multiple notches 542 that penetrate in the thickness direction (Z-axis direction) of the metal connector 5. This makes it possible to prevent the semiconductor device 1 from having poor bonding between the semiconductor chip 14 and the metal connector 5 due to the Manhattan effect after the reflow process.

[0058] In other words, the metal connector 5 of the semiconductor device in this embodiment has, for example, two notches 542, and thus has three other end sides 53b that are discontinuous in the Y-axis direction. Suppose that during the reflow process, the molten and liquefied second bonding material 301d flows from the placement surface 301a to the three other end sides 53b of the metal connector 5. In the discontinuous gap in the Y-axis direction between the other end side 53c of the third portion 53 and the inclined surface 305a of the metal frame 30, the liquefied second bonding material 301d does not become a continuous whole in the Y-axis direction. Therefore, it generates almost no surface tension that pulls the metal connector 5 diagonally downward toward the inclined surface 305a side.

[0059] Furthermore, the notch 542 formed in the metal connector 5 allows the center of gravity of the metal connector 5 to be moved closer to the first part 51 side (for example, by 50 μm) compared to the case of the metal connector 5A shown in Figure 6. In this embodiment, since the weight of the third part 53 of the metal connector 5 of the semiconductor device 1 is greater than the weight of the first part 51, the presence of the notch 542 shifts the center of gravity of the metal connector 5 towards the first part 51 side, thereby preventing the first part 51 side from being lifted.

[0060] As described above, the lifting of the first portion 51 is suppressed, and the semiconductor device 1 shown in Figures 1 to 3, after the cooling and solidification of the molten first bonding material 515 and the second bonding material 301d, can be in a state where no bonding defects occur with the semiconductor chip 14 of the metal connector 5, as shown in Figure 2.

[0061] After the reflow process is completed, a sealing material 19 is formed. The sealing material 19 is formed to seal the joint between the first lead frame 10 and the semiconductor chip 14, the joint between the first electrode 141 and the metal connector 5, the joint between the metal connector 5 and the metal frame 30, the joint between the second electrode 142 and the source connector 40, and the joint between the source connector 40 and the second lead frame 12.

[0062] As described above, the semiconductor device 1 of this embodiment includes a metal frame 30 comprising a mounting surface 301a on which the second bonding material 301d is disposed, and an inclined surface 305a adjacent to the mounting surface 301a and inclined at a predetermined angle with respect to the mounting surface 301a, and a metal connector 5 comprising a first portion 51 connected to the first bonding material 515 and forming one end, a second portion 52 integrally connected to the first portion 51 and formed to rise toward the metal frame 30, and the second portion 52 The third portion 53 is integrally connected to the other end and forms the other end; a connecting surface 53a is formed on the third portion 53 and connected to the second joining material 301d; another end surface 53b is formed on the third portion 53, is adjacent to the connecting surface 53a and faces the inclined surface 305a of the metal frame 30; and a notch 542 is provided that opens on the other end surface 53b and penetrates through the third portion 53 in the thickness direction. This makes it possible to prevent joining defects due to the Manhattan effect.

[0063] Furthermore, in the semiconductor device 1 of this embodiment, in the direction (X-axis direction) where the inclined surface 305a of the metal frame 30 and the other end side surface 53b of the metal connector 5 face each other, the length L1 of the notch 542 of the metal connector 5 is longer than the distance L2 (maximum distance L2) between the inclined surface 502a of the metal frame 30 and the other end side surface 53b of the metal connector 5. Therefore, during the reflow process, it is possible to prevent the second bonding material 301d from entering the notch 542 and integrating with the second bonding material 301d that has wrapped around into the gap between the other end side surface 53b of the metal connector 5 and the inclined surface 305a of the metal frame 30. As a result, it is possible to more reliably suppress the generation of surface tension that pulls the metal connector 5 diagonally downward toward the inclined surface 305a.

[0064] In the semiconductor device 1 of this embodiment, as shown in Figures 1 to 3, the notch 542 of the metal connector 5 is formed to be rectangular when the metal connector 5 is viewed from above. However, even when the notch of the metal connector 5 is a semicircular notch 543 as shown in Figure 4, or a V-shaped notch 544 as shown in Figure 5, the occurrence of bonding failure due to the Manhattan effect can be suppressed in the same way as described above. Furthermore, for example, the shape and size of the notch of the metal connector 5 may be appropriately selected with the aim of shifting the position of the center of gravity of the metal connector 5 by a predetermined distance toward the first part 51 to set it to an optimal position.

[0065] While embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included within the scope and spirit of the invention, as well as within the scope of the invention and its equivalents as described in the claims. [Explanation of Symbols]

[0066] 1: Semiconductor equipment 10: First lead frame 12: Second lead frame 30: Metal frame (3rd lead frame) 301a: Installation surface 301d: Second bonding material 305a: Slanted surface 14: Semiconductor chips 141: First electrode (gate electrode) 142: Second electrode (source electrode) 143: Third electrode (drain electrode) 19: Sealing material 40: Source Connector 5: Metal connector (gate connector) 51: 1st part 515: 1st bonding material 52:Second part 53: Third part 53a: Connecting surface 53b: Other end side 542: Rectangular cutout 543: Semicircular notch 544: V-shaped notch

Claims

1. A semiconductor chip having electrodes, A first bonding material provided on the electrode of the semiconductor chip, A metal frame disposed at a distance from the aforementioned semiconductor chip, A second joining member provided on the metal frame, The system comprises a metal connector connected to the semiconductor chip via the first bonding material and connected to the metal frame via the second bonding material, The metal frame comprises an arrangement surface on which the second joining material is disposed, and an inclined surface adjacent to the arrangement surface and inclined at a predetermined angle with respect to the arrangement surface. The semiconductor device comprises a metal connector having a first portion connected to the first joining material and forming one end, a second portion integrally connected to the first portion and formed to rise toward the metal frame, a third portion integrally connected to the second portion and forming the other end, a connecting surface formed in the third portion and connected to the second joining material, a side surface formed in the third portion adjacent to the connecting surface and facing the inclined surface of the metal frame, and a notch opening in the side surface and penetrating through the third portion in the thickness direction.

2. The direction perpendicular to the direction in which the inclined surface of the metal frame and the other end surface of the metal connector face each other and the thickness direction is defined as the width direction of the metal connector. The semiconductor device according to claim 1, wherein the length of the third portion in the width direction is set to be greater than the length of the first portion in the width direction, and the weight of the third portion is greater than the weight of the first portion.

3. The semiconductor device according to claim 1 or claim 2, wherein, in the direction in which the inclined surface of the metal frame and the other end surface of the metal connector face each other, the length of the notch of the metal connector is longer than the distance between the inclined surface of the metal frame and the other end surface of the metal connector.

4. The semiconductor device according to claim 1 or claim 2, wherein the electrode is a gate electrode and the metal connector is a gate connector.

5. The semiconductor device according to claim 1, wherein the notch is rectangular, semicircular, or V-shaped in the metal connector when viewed from above.

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