Lead frame, semiconductor device, and method for manufacturing semiconductor device

Abstract

This lead frame (100) comprises: an N lead (101), both ends of which are connected to an outer frame (7), and which has an N electrode (1) on either one of the both ends; and a P lead (102), which is provided side by side with the N lead (101) with a gap therebetween, both ends of which are connected to the outer frame (7), and which has a P electrode (2) on either one of the both ends. The lead frame (100) also comprises: an AC lead (103) which is provided side by side with the N lead (101) and the P lead (102) with a gap therebetween, has an AC electrode (3) having a base end portion connected to the outer frame (7), and has a tip portion serving as a free end; and an insulating support member (8) which connects the AC lead (103) and the N lead (101) and supports the AC lead (103). At least one of the N electrode (1) and the P electrode (2) is provided on the side opposite to the side on which the AC electrode (3) is disposed.

Description

Lead Frame, Semiconductor Device, and Method of Manufacturing Semiconductor Device

[0001] The present disclosure relates to a lead frame, a semiconductor device, and a method of manufacturing a semiconductor device.

[0002] In a conventional lead frame, a suspension lead is provided at a portion of a lead opposite to an electrode connected to an outer frame, and the suspension lead is connected to the outer frame to suppress drooping of the lead (see, for example, Patent Document 1).

[0003] Japanese Patent Application Laid-Open No. 2019-75524 (FIG. 21)

[0004] However, in the case of a lead frame encapsulated with resin, an insulation distance needs to be provided between an adjacent suspension lead and an electrode with respect to an electrode or a suspension lead that is not encapsulated with resin and is exposed to the outside. For example, when three leads are arranged side by side and a suspension lead is provided on a central lead sandwiched between two leads, an insulation distance needs to be provided between this suspension lead and at least one electrode of the two leads. Therefore, the size of the encapsulated resin body increases. Here, a structure in which a suspension lead is not provided on the central lead in order not to increase the size of the encapsulated resin body can be considered, but in this case, there is a problem that the central lead droops.

[0005] The present disclosure has been made to solve the above problems, and provides a lead frame, a semiconductor device, and a method of manufacturing a semiconductor device that can suppress drooping of a central lead without providing a suspension lead on the central lead sandwiched between two leads.

[0006] The lead frame according to this disclosure comprises a first double-ended support lead having both ends connected to an outer frame and a first electrode on one of its ends, a second double-ended support lead provided at a distance from the first double-ended support lead and having both ends connected to an outer frame and a second electrode on one of its ends, and a one-ended support lead provided at a distance from the first double-ended support lead and the second double-ended support lead and having a third electrode whose base end is connected to an outer frame and whose tip end is a free end. The lead frame further comprises an insulating support member that connects the one-ended support lead and the first double-ended support lead and supports the one-ended support lead, wherein at least one of the first electrode and the second electrode is provided on the side opposite to the side on which the third electrode is located.

[0007] The semiconductor device according to this disclosure comprises a lead frame on which semiconductor elements are mounted in a single row on one side, a sealing resin body formed inward from the outer circumference of the lead frame, a heat dissipation insulating sheet attached to the side opposite to the side on which the semiconductor elements are mounted, and a cooler attached to the lead frame via the heat dissipation insulating sheet. The lead frame comprises a first double-ended support lead whose ends extend outward from the sealing resin body and which has a first electrode on one of its ends, a second double-ended support lead provided at a distance from the first double-ended support lead, whose ends extend outward from the sealing resin body and which has a second electrode on one of its ends, and a single-ended support lead provided at a distance from the first double-ended support lead and the second double-ended support lead, which has a third electrode whose base end extends outward from the sealing resin body and whose tip end is provided inside the sealing resin body. The lead frame comprises an insulating support member that connects a one-end supported lead and a first double-ended supported lead, and at least one of the first electrode and the second electrode is provided on the side opposite to the side where the third electrode is located.

[0008] The method for manufacturing a semiconductor device according to this disclosure involves mounting semiconductor elements in a single row on one side of a lead frame and attaching an insulating support member, and on the opposite side of the lead frame from the side on which the semiconductor elements are mounted, arranging a heat dissipation insulating sheet and a cooler in that order, and then molding a sealing resin body that seals the lead frame, heat dissipation insulating sheet and cooler by transfer molding.

[0009] According to this disclosure, it is possible to obtain a lead frame, a semiconductor device, and a method for manufacturing a semiconductor device that can suppress lead sagging while preventing an increase in the size of the sealing resin body, even without providing a suspension lead on the lead sandwiched between two leads.

[0010] This is a top view of the lead frame before tie bar cutting in Embodiment 1 (after semiconductor elements are mounted and bonding wires are installed). This is a top view of the lead frame before tie bar cutting in Embodiment 1 (after semiconductor elements are mounted and metal plates are installed). This is a top view of the semiconductor device in Embodiment 1. This is a top view visualizing the sealing resin body of the semiconductor device in Embodiment 1. This is a cross-sectional view of the section line A-A in Figure 1 in Embodiment 1. This is a top view of the lead frame before tie bar cutting in Embodiment 2 (after semiconductor elements are mounted and bonding wires are installed). This is a top view of the lead frame before tie bar cutting in Embodiment 3 (after semiconductor elements are mounted and bonding wires are installed). This is a top view of the lead frame before tie bar cutting in Embodiment 4 (after semiconductor elements are mounted and bonding wires are installed).

[0011] Embodiment 1. The semiconductor device 500 in Embodiment 1 is a transfer-molded semiconductor device that is mounted on an inverter and has a lead frame 100 on which semiconductor elements 11 are mounted. The lead frame 100, the semiconductor device 500, and the manufacturing method of the semiconductor device 500 will be described based on Figures 1 to 5. For convenience, the signal terminals are not shown in Figures 1 to 5.

[0012] In the following explanation, we will refer to the X-Y-Z axes shown in the figure as needed to facilitate the explanation. ***Explanation of Lead Frame 100*** First, we will explain the configuration of the lead frame 100 in Embodiment 1. Figure 1 is a top view of the lead frame in Embodiment 1 before tie bar cutting (after semiconductor elements are mounted and bonding wires are installed). The X-Y-Z axes are shown with the direction from left to right on the page corresponding to the +X direction, the direction from bottom to top on the page corresponding to the +Y direction, and the direction from back to front on the page corresponding to the +Z direction.

[0013] In Figure 1, the lead frame 100 comprises a rectangular annular outer frame 7 formed to surround the outer circumference, an N (negative electrode) lead 101, a P (positive electrode) lead 102 arranged at a distance from the N lead 101, and an AC (output) lead 103 arranged at a distance between the N lead 101 and the P lead 102.

[0014] The N lead 101 has both ends connected to the outer frame 7 and has an N (negative) electrode 1 at one end. The P lead 102 has both ends connected to the outer frame 7 and has a P (positive) electrode 2 at one end. Furthermore, the AC lead 103 has the other end (base end) connected to the outer frame 7 and has an AC (output) electrode 3 at the other end. One end (tip) of the AC lead 103 is a free end.

[0015] A semiconductor element 11 is mounted on the upper surface (the surface in the +Z direction) of the P lead 102 and the AC lead 103. An insulating support member 8 is provided between the N lead 101 and the AC lead 103, connecting the N lead 101 and the AC lead 103 and supporting the AC lead 103.

[0016] An N lead 101 is connected to the outer frame 7 on the -X side via an N electrode 1, and a P lead 102 is connected to the outer frame 7 on the -X side via a P electrode 2, on the -Y side of the outer frame 7 on the -X side than the N lead 101. An AC lead 103 is connected to the outer frame 7 on the +X side, which is opposite to the N electrode 1 and P electrode 2, via an AC electrode 3.

[0017] The lead frame 100 is made of copper. While it is preferable that the lead frame 100 be made of copper or a copper-based alloy, any material with electrical and thermal conductivity may be used.

[0018] The outer frame 7 is formed in a rectangular ring shape, and inside the outer frame 7, the N lead 101, AC lead 103, and P lead 102 are installed in that order from the +Y direction side, with gaps between them. In addition, tie bars 12 are provided on the outer frame 7 on the +Y direction side, installed with gaps between the N leads 101. Furthermore, tie bars 13 are provided on the outer frame 7 on the -Y direction side, installed with gaps between the P leads 102.

[0019] Both tie bars 12 and 13 have a rectangular parallelepiped shape extending in the X direction. Both ends of tie bars 12 and 13 are connected to the outer frame 7. Furthermore, a suspension lead 4 extending in the +Y direction from an N lead 101 is connected to tie bar 12. Also, a suspension lead 5 extending in the -Y direction from a P lead 102 is connected to tie bar 13.

[0020] The N lead 101, P lead 102, and AC lead 103 all have a rectangular parallelepiped shape extending in the X direction. The N lead 101 and P lead 102 are arranged side by side with a gap between them, and the AC lead 103 is arranged side by side with a gap between the N lead 101 and P lead 102. The N lead 101 has an N electrode 1 at its -X direction end, the P lead 102 has a P electrode 2 at its -X direction end, and the AC lead 103 has an AC electrode 3 at its +X direction end.

[0021] The N lead 101 is an example of a first double-ended support lead. The N lead 101 has its -X end connected to the outer frame 7 via the N electrode 1, and its +X end connected to the tie bar 12 of the outer frame 7 via the suspension lead 4. Thus, since both ends of the N lead 101, on the -X and +X sides, are connected to the outer frame 7, it can be said that both ends are supported by the outer frame 7. In the Y direction, multiple signal terminals (not shown) are installed in the gap between the N lead 101 and the tie bar 12, extending from the outer circumference of the outer frame 7 on the +Y side toward the N lead 101.

[0022] Furthermore, the first double-ended support lead, N lead 101, branches in the -Y direction from the side facing the AC lead 103 and has a double-ended support lead side projection 14 that protrudes along one end (tip) of the AC lead 103.

[0023] The P lead 102 is an example of a second double-ended support lead. The P lead 102 has its -X end connected to the outer frame 7 via the P electrode 2, and its +X end connected to the tie bar 13 via the suspension lead 5. Thus, since both ends of the P lead 102, on the -X and +X sides, are connected to the outer frame 7, it can be said that both ends are supported by the outer frame 7. In the gap between the P lead 102 and the tie bar 13 in the Y direction, several signal terminals (not shown) are installed, extending from the outer circumference of the outer frame 7 on the -Y side toward the P lead 102. In addition, semiconductor elements 11 are mounted in a row on the upper surface (the +Z side) of the P lead 102.

[0024] The AC lead 103 is an example of a one-end supported lead. The end of the AC lead 103 on the +X side is connected to the outer frame 7 via the AC electrode 3, but the end on the -X side is not connected to the outer frame 7. Therefore, it can be said that the AC lead 103 is supported by the outer frame 7 at one end in the X direction. Furthermore, it can be said that the end of the AC lead 103 on the -X side is a free end. In addition, semiconductor elements 11 are mounted in a row on the upper surface (the surface on the +Z side) of the AC lead 103.

[0025] The suspension lead 4 extends in the +Y direction, which is perpendicular to the longitudinal direction of the N lead 101, from near the tip of the end of the N lead 101 opposite to the N electrode 1 (the +X direction side). The suspension lead 4 is connected to the tie bar 12 of the outer frame 7. Since the N lead 101 is connected to the outer frame 7 via the suspension lead 4, it can also be said that the N lead 101 is suspended from the outer frame 7, and the suspension lead 4 plays the role of fixing the N lead 101 to the outer frame 7. The suspension lead 5 extends in the -Y direction, which is perpendicular to the longitudinal direction of the P lead 102, from near the tip of the end of the P lead 102 opposite to the P electrode 2 (the +X direction side). The suspension lead 5 is connected to the tie bar 13 of the outer frame 7. Since the P-lead 102 is connected to the outer frame 7 via the suspension lead 5, it can also be said that the P-lead 102 is suspended from the outer frame 7, and the suspension lead 5 plays the role of fixing the P-lead 102 to the outer frame 7.

[0026] The semiconductor elements 11 are mounted in a single row on the upper surface (the +Z direction side) of the P lead 102 and AC lead 103. The semiconductor elements 11 are, for example, power semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors), MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), and diodes. The power semiconductor elements may also be RC-IGBTs (Reverse-Conducting IGBTs) in which the IGBT and freewheeling diode are formed on a single semiconductor substrate. Note that the semiconductor elements 11 are not limited to power semiconductor elements.

[0027] The semiconductor chip constituting the semiconductor element 11 is preferably made of silicon (Si), but is not limited to silicon (Si). Examples of semiconductor chips for the semiconductor element 11 include silicon carbide (SiC), gallium nitride-based materials (e.g., gallium nitride (GaN)), and diamond. The semiconductor chip constituting the semiconductor element 11 may use one of these materials alone or in combination.

[0028] The upper surface (+Z side) of the semiconductor element 11, which is placed on the upper surface (+Z side) of the P lead 102, and the upper surface (+Z side) of the AC lead 103 are electrically connected using a bonding wire 15. Similarly, the upper surface (+Z side) of the semiconductor element 11, which is placed on the upper surface (+Z side) of the AC lead 103, and the upper surface (+Z side) of the N lead 101 are electrically connected using a bonding wire 15. The bonding wire 15 is preferably made of aluminum, which has high bonding reliability, but it may also be made of copper, gold, or silver.

[0029] Alternatively, instead of the bonding wire 15, a metal plate 16 made of metal may be installed. Figure 2 is a top view of the lead frame before tie bar cutting in Embodiment 1 (after mounting semiconductor elements and installing the metal plate). In Figure 2, the lead frame 100 uses a metal plate 16 instead of bonding wire 15. In the lead frame 100, the semiconductor elements 11 are soldered to the upper surfaces (+Z direction side) of the P lead 102 and AC lead 103, and at the same time, the metal plate 16 is also fixed to a predetermined position on the lead frame 100 by soldering.

[0030] N electrode 1 is an example of a first electrode. N electrode 1 is connected to the negative side of the bias power supply.

[0031] P electrode 2 is an example of a second electrode. P electrode 2 is connected to the positive side of the bias power supply.

[0032] AC electrode 3 is an example of a third electrode. AC electrode 3 is responsible for outputting the output signal from the inverter.

[0033] The insulating support member 8 has a rectangular parallelepiped shape. The insulating support member 8 is a ceramic chip component. The insulating support member 8 is made of either aluminum nitride or silicon nitride and has metal pieces at both ends. The metal pieces are electrodes made of a metal such as nickel, but the insulating support member 8 is a ceramic insulating component and is not used in electrical circuits for conductivity, but rather for purposes such as heat dissipation. The metal pieces are used to solder the insulating support member 8 to the lead frame 100.

[0034] The insulating support member 8 is aligned longitudinally with the X direction. One of the metal pieces at both ends of the insulating support member 8 is soldered to the upper surface (the +Z direction side) of the protruding portion 14 on the end support lead side of the first end-supported lead, the N lead 101. The other metal piece at both ends of the insulating support member 8 is soldered to the upper surface (the +Z direction side) near the tip of the -X direction end of the one-end support lead, the AC lead 103. As a result, the insulating support member 8 connects the N lead 101 and the AC lead 103.

[0035] Furthermore, the surface on which the insulating support member 8, which is a ceramic chip component, is installed is the same as the surface on which the semiconductor element 11 is mounted, which is the upper surface (+Z direction side) of the lead frame 100. Therefore, in the manufacturing process of the semiconductor device 500, when the semiconductor element 11 is installed on the P lead 102 and AC lead 103 by soldering, the insulating support member 8 is simultaneously installed by soldering on the upper surface (+Z direction side) of the end support lead side projection 14 of the N lead 101 and on the upper surface (+Z direction side) near the tip of the -X direction end of the AC lead 103, which is a single-end support lead.

[0036] In Embodiment 1, the insulating support member 8 may be a resin piece made of epoxy resin. The insulating support member 8, which is a resin piece made of epoxy resin, is bonded to the lead frame 100 via an epoxy adhesive or a silicone adhesive. The insulating support member 8 is aligned longitudinally with the X direction. One end of the insulating support member 8 in the X direction is bonded via adhesive to the upper surface (the +Z direction side surface) of the end-support lead side projection 14 of the N lead 101, which is the first end-support lead. The other end of the insulating support member 8 in the X direction is bonded via adhesive to the upper surface (the +Z direction side surface) near the tip of the -X direction end of the AC lead 103, which is a one-end support lead. As a result, the insulating support member 8 connects the N lead 101 and the AC lead 103.

[0037] Furthermore, the insulating support member 8 in Embodiment 1 may be a resin piece made of silicone resin. The insulating support member 8, which is a resin piece made of silicone resin, is bonded to the lead frame 100 via an epoxy adhesive or a silicone adhesive. The insulating support member 8 is aligned longitudinally with the X direction. One of the X-direction ends of the insulating support member 8 is bonded via adhesive to the upper surface (+Z direction side) of the double-ended support lead side projection 14 of the N lead 101, which is the first double-ended support lead, and to the upper surface (+Z direction side) near the tip of the -X direction end of the AC lead 103, which is the one-ended support lead. As a result, the insulating support member 8 connects the N lead 101 and the AC lead 103. The silicone resin piece is made of a low-elasticity material, such as rubber.

[0038] ***Explanation of the effects of the lead frame 100*** The lead frame 100 in Embodiment 1 comprises an N lead 101 whose both ends are connected to the outer frame 7 and which has an N electrode 1 on one of its ends, and a P lead 102 which is provided side by side with a gap between it and the N lead 101, whose both ends are connected to the outer frame 7 and which has a P electrode 2 on one of its ends. The lead frame 100 in Embodiment 1 also comprises an AC lead 103 which is provided side by side with a gap between it and the N lead 101 and the P lead 102, which has an AC electrode 3 whose base end is connected to the outer frame 7 and whose tip is a free end, and an insulating support member 8 which connects the AC lead 103 and the N lead 101 and supports the AC lead 103. At least one of the N electrode 1 and the P electrode 2 is provided on the side opposite to the side on which the AC electrode 3 is located.

[0039] In the first embodiment, the lead frame 100 has the following configuration: the AC lead 103, which is provided between the N lead 101 and the P lead 102, is supported by the insulating support member 8, for example, by the free end of its tip being connected to the N lead 101 by the insulating support member 8. In other words, the tip of the AC lead 103 is held at the installation height of the insulating support member 8. With this configuration, sagging of the AC lead 103 can be suppressed without providing a suspension lead to the AC lead 103 sandwiched between the N lead 101 and the P lead 102. Furthermore, since sagging of the tip of the AC lead 103 can be suppressed by providing the insulating support member 8, there is no need to provide a new suspension lead to the tip of the AC lead 103. Therefore, since it is not necessary to ensure an insulating distance between at least one of the N electrode 1 and P electrode 2, which are provided on the side opposite to the side where the AC electrode 3 is located, and the suspension lead, the size of the sealing resin body 6 that covers the inside of the outer circumference of the lead frame 100 can be reduced compared to when a suspension lead is provided at the tip of the AC lead 103. The sealing resin body 6 will be described later.

[0040] Furthermore, in the lead frame 100 of Embodiment 1, semiconductor elements 11 are mounted in a single row on one side of the P lead 102 and AC lead 103, and the insulating support member 8 is provided on the same side as the side on which the semiconductor elements 11 are mounted. The insulating support member 8 is a ceramic chip component and can be fixed to the lead frame 100 by soldering, so in the process of mounting the semiconductor elements 11 by soldering, the insulating support member 8 can be installed at a predetermined position on the lead frame 100 at the same time as the semiconductor elements 11. With this configuration, the manufacturing of the lead frame 100 becomes easier.

[0041] Furthermore, in Embodiment 1, the N lead 101 branches off from the side facing the AC lead 103 and has a double-ended support lead side projection 14 that protrudes along the tip of the AC lead 103, and the insulating support member 8 connects the double-ended support lead side projection 14 and the AC lead 103. The insulating support member 8 is installed on the upper surface (+Z direction side) of the lead frame 100 in a location where the semiconductor element 11 and bonding wire 15 are not installed. Therefore, since the semiconductor element 11 and bonding wire 15 are not installed on the double-ended support lead side projection 14, it becomes easier to position the insulating support member 8 when attaching it to the lead frame 100. Also, in Embodiment 1, the installation direction of the insulating support member 8 is the X direction, which allows for a smaller longitudinal size of the insulating support member 8 compared to, for example, installing it in an oblique direction.

[0042] Also, in Embodiment 1, as the insulating support member 8, a ceramic chip component is used. With such a configuration, not only can the leads be connected in an electrically independent state, but since a chip component formed of a material with high thermal conductivity is used as the insulating support member 8, the heat dissipation with respect to the heat generated from the semiconductor element 11 can be enhanced. As the ceramic chip component, for example, aluminum nitride or silicon nitride is used. Further, the insulating support member 8, which is a ceramic chip component, has metal pieces at both ends. By soldering at the portions of the metal pieces at both ends of the insulating support member 8, the insulating support member 8 can be installed on the lead frame 100, so the insulating support member 8 can be attached to the lead frame 100 more firmly than when installed using an adhesive.

[0043] Also, in Embodiment 1, as the insulating support member 8, a resin piece made of epoxy resin or silicone resin may be used. In this case, the insulating support member 8 is attached to the lead frame 100 using an adhesive. As a result, the material is less expensive than using a ceramic chip component having metal pieces at both ends as the insulating support member 8, and further, since it has a simple shape of a rectangular parallelepiped, the insulating support member 8 can be manufactured more easily.

[0044] Here, when the resin piece made of epoxy resin or silicone resin is the insulating support member 8, after the insulating support member 8 is adhered to the lead frame 100 using an epoxy-based adhesive or a silicone-based adhesive, the situation when a plurality of semiconductor elements 11 are installed on the lead frame 100 by soldering will be described. During soldering, the portion of the lead frame 100 where the semiconductor element 11 is mounted becomes particularly hot to melt the solder, and a temperature change occurs in the entire lead frame 100. Due to this temperature change, the lead frame 100 and the semiconductor element 11 deform due to thermal expansion or thermal contraction. In the lead frame 100, warpage in the Z direction may occur. At this time, since the linear expansion coefficients of the lead frame 100 and the semiconductor element 11 are different, the deformation amounts of the N lead 101 where the semiconductor element 11 is not mounted and the P lead 102 and AC lead 103 where the semiconductor element 11 is mounted in the lead frame 100 may be different.

[0045] In the first embodiment, since the semiconductor element 11 is not mounted on the N lead 101, the deformation amount is smaller than that of the P lead 102 or the AC lead 103. However, since the N lead 101 where the semiconductor element 11 is not mounted and the AC lead 103 where the semiconductor element 11 is mounted are connected by the insulating support member 8, the deformation amount of the N lead 101 becomes larger and the deformation of the entire lead frame 100 also becomes larger than when not connected.

[0046] However, the resin piece made of silicone resin is, for example, rubber and is formed of a low-elasticity material, so it is more likely to deform than the lead frame 100. Therefore, stress concentration on the connected N lead 101 and AC lead 103 can be alleviated, and warpage of the entire lead frame 100 can be reduced.

[0047] Further, due to the deformation of the lead frame 100 and the semiconductor element 11 caused by temperature change, stress is applied to the epoxy-based adhesive or silicone-based adhesive that adheres the insulating support member 8 to the lead frame 100.

[0048] However, if the insulating support member 8 is a resin piece made of silicone resin, for example, rubber, it is made of a low-elasticity material and is more easily deformed. Therefore, stress concentration on the epoxy adhesive or silicone adhesive can be alleviated, and even when the semiconductor element 11 is soldered to the lead frame 100, the insulating support member 8 is less likely to peel off from the lead frame 100.

[0049] Furthermore, while it is preferable that the silicone resin pieces be formed from a cured epoxy adhesive or a material with a lower elastic modulus than the silicone adhesive, the invention is not limited to these.

[0050] Furthermore, the insulating support member 8 is not limited to a rectangular parallelepiped shape; for example, it may have a cubic shape.

[0051] Furthermore, although the insulating support member 8 was connected in the X direction in Embodiment 1, it is not limited to that direction, and may be connected in the Y direction or diagonally. The insulating support member 8 can be installed on the same surface of the lead frame 100 as the surface on which the semiconductor element 11 is installed, but in a location where the semiconductor element 11 and bonding wire 15 are not installed. Moreover, the position where the insulating support member 8 is installed is not limited to the tip of the AC lead 103, but may be other than the tip of the AC lead 103.

[0052] Furthermore, the first double-ended support lead may be either an N lead 101 or a P lead 102.

[0053] ***Description of Semiconductor Device 500*** Next, the semiconductor device 500 will be described. Figure 3 is a top view of the semiconductor device 500 in Embodiment 1. Figure 4 is a top view visualizing the inside of the sealing resin body 6 of the semiconductor device 500 in Embodiment 1. Figure 5 is a cross-sectional view taken along the cross-sectional line A-A in Figure 3.

[0054] In Figures 3, 4, and 5, the semiconductor device 500 comprises a lead frame 100 on which semiconductor elements 11 are mounted in a single row on one side, a sealing resin body 6 covering the inside of the outer circumference of the lead frame 100, a heat dissipation insulating sheet 9 attached to the side opposite to the side on which the semiconductor elements 11 are mounted, and a cooler 10 attached to the lead frame 100 via the heat dissipation insulating sheet 9. The lead frame 100 comprises an N lead 101, a P lead 102, and an AC lead 103.

[0055] The N lead 101 extends both ends outside the sealing resin body 6, and has an N electrode 1 at one end. The P lead 102 extends both ends outside the sealing resin body 6, and has a P electrode 2 at one end. Furthermore, the AC lead 103 has the other end (base end) extending outside the sealing resin body 6, and has an AC electrode 3 at the other end. One end (tip) of the AC lead 103 is located inside the sealing resin body 6.

[0056] A semiconductor element 11 is mounted in a single row on the upper surface (the surface in the +Z direction) of the P lead 102 and the AC lead 103. An insulating support member 8 is provided between the N lead 101 and the AC lead 103, connecting the N lead 101 and the AC lead 103 and supporting the AC lead 103.

[0057] A heat-dissipating insulating sheet 9 is attached to the lower surface (the side in the -Z direction) (the side opposite to the side on which the semiconductor element 11 is mounted) of the N lead 101, P lead 102, and AC lead 103. A cooler 10 is attached to the lower surface (the side in the -Z direction) of the heat-dissipating insulating sheet 9. The cooler 10 has a portion that is sealed by the sealing resin body 6 and a portion that is not sealed by the sealing resin body 6.

[0058] In the state before tie bar cutting, when the outer frame 7 including tie bars 12 and 13 is removed, the N electrode 1, N lead 101, P electrode 2, P lead 102, AC electrode 3, AC lead 103, suspension lead 4 and suspension lead 5 are formed as a lead frame 100 integrated with the outer frame 7, as shown in Figure 1.

[0059] The sealing resin body 6 is formed inside the outer frame 7 of the lead frame 100, which has an outer frame 7 surrounding it as shown in Figure 1. The semiconductor device 500 is the final form after the outer frame 7 has been removed following the formation of the sealing resin body 6. The resin material of the sealing resin body 6 can be any thermosetting resin, for example, an epoxy resin material to which an insulating inorganic filler has been added. Examples of insulating inorganic fillers include aluminum nitride, silicon nitride, boron nitride, alumina (aluminum oxide), crystalline silica (silicon dioxide (SiO2) ２ )) etc. Also, since heat dissipation is not essential for the sealing resin body 6 in Embodiment 1, in addition to inorganic fillers, fused silica (silicon dioxide (SiO) ２ You may also use ))

[0060] The semiconductor device 500 is equipped with three electrodes, from the first to the third. The first electrode, the N electrode 1, is connected to the negative side of the bias power supply, and the second electrode, the P electrode 2, is connected to the positive side of the bias power supply. The third electrode, the AC electrode 3, is responsible for outputting the output signal from the inverter.

[0061] The N lead 101, P lead 102, and AC lead 103 all have a rectangular parallelepiped shape extending in the X direction. The N lead 101 and P lead 102 are arranged side by side with a gap between them, and the AC lead 103 is arranged side by side with a gap between the N lead 101 and P lead 102. The N lead 101 has an N electrode 1 at its -X direction end, the P lead 102 has a P electrode 2 at its -X direction end, and the AC lead 103 has an AC electrode 3 at its +X direction end.

[0062] The N-lead 101 is an example of a first double-ended support lead. The N-lead 101 has both ends extending outside the sealing resin body 6, and in the state before tie bar cutting to remove the outer frame 7, the N-electrode 1 and the suspension lead 4 are connected to the outer frame 7, as shown in Figure 1. Therefore, it can be said that the N-lead 101 is supported by the outer frame 7 at both ends via the N-electrode 1 and the suspension lead 4.

[0063] The first double-ended support lead, N lead 101, branches in the -Y direction from the side facing AC lead 103 and has a double-ended support lead side projection 14 that protrudes along one end (tip) of AC lead 103.

[0064] The P-lead 102 is an example of a second double-ended support lead. The P-lead 102 has both ends extending outside the sealing resin body 6, and in the state before tie-bar cutting to remove the outer frame 7, the P-electrode 2 and the suspension lead 5 are connected to the outer frame 7, as shown in Figure 1. Therefore, it can be said that the P-lead 102 is supported by the outer frame 7 at both ends via the P-electrode 2 and the suspension lead 5.

[0065] The AC lead 103 is an example of a one-end supported lead. The other end (base end) of the AC lead 103 extends outside the sealing resin body 6, and in the state before tie bar cutting to remove the outer frame 7, as shown in Figure 1, the AC electrode 3 at the other end is connected to the outer frame 7. Therefore, it can be said that the other end (base end) of the AC lead 103 is supported by the outer frame 7 via the AC electrode 3.

[0066] The suspension lead 4 extends from near the tip of the end of the N lead 101 opposite to the N electrode 1 (on the +X direction side) in the +Y direction, which is perpendicular to the longitudinal direction of the N lead 101. In the state of the lead frame 100 in Figure 1, the suspension lead 4 is connected to the outer frame 7. Being connected to the outer frame 7 can also be said to mean that the N lead 101 is suspended from the outer frame 7, and the suspension lead 4 plays the role of fixing the N lead 101 to the outer frame 7. Similarly, the suspension lead 5 extends from near the tip of the end of the P lead 102 opposite to the P electrode 2 (on the +X direction side) in the P lead 102 in the -Y direction, which is perpendicular to the longitudinal direction of the P lead 102. In the state of the lead frame 100 in Figure 1, the suspension lead 5 is connected to the outer frame 7. Being connected to the outer frame 7 can also be said to mean that the P lead 102 is suspended from the outer frame 7, and the suspension lead 5 plays the role of fixing the P lead 102 to the outer frame 7.

[0067] The semiconductor elements 11 are mounted in a single row on the upper surface (the +Z direction side) of the P lead 102 and AC lead 103. The semiconductor elements 11 are, for example, power semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors), MOSFETs (Metal Oxide Semiconductor Field Effect Transistors), and diodes. The power semiconductor elements may also be RC-IGBTs (Reverse-Conducting IGBTs) in which the IGBT and freewheeling diode are formed on a single semiconductor substrate. Note that the semiconductor elements 11 are not limited to power semiconductor elements.

[0068] The semiconductor chip constituting the semiconductor element 11 is preferably made of silicon (Si), but is not limited to silicon (Si). Examples of semiconductor chips for the semiconductor element 11 include silicon carbide (SiC), gallium nitride-based materials (e.g., gallium nitride (GaN)), and diamond. The semiconductor chip constituting the semiconductor element 11 may use one of these materials alone or in combination.

[0069] The heat dissipation insulating sheet 9 is placed on the side of the lead frame 100 opposite to the side on which the semiconductor element 11 is mounted (the side in the -Z direction). The heat dissipation insulating sheet 9 is attached in close contact with the lead frame 100, and the entire heat dissipation insulating sheet 9 is covered by the sealing resin body 6. The heat dissipation insulating sheet 9 is, for example, an insulating resin to which a highly thermally conductive inorganic filler has been added. Examples of highly thermally conductive inorganic fillers include aluminum nitride, silicon nitride, boron nitride, alumina (aluminum oxide), crystalline silica (silicon dioxide (SiO2) ２ It is an epoxy resin to which insulating and highly thermally conductive inorganic fillers such as )) are added. The heat dissipation insulating sheet 9 has the function of bonding the lead frame 100 and the cooler 10. Furthermore, since the heat dissipation insulating sheet 9 is an insulating resin, it plays a role in electrically insulating the lead frame 100 and the cooler 10, and also plays a role in dissipating the heat generated from the semiconductor element 11 to the cooler 10.

[0070] The cooler 10 is positioned on the side of the heat-dissipating insulating sheet 9 opposite to the side to which the lead frame 100 is attached (the side in the -Z direction). The cooler 10 is mounted in close contact with the heat-dissipating insulating sheet 9. Part of the cooler 10 (part on the +Z direction side) is covered inside the sealing resin body 6, while the other part of the cooler 10 (part on the -Z direction side) is exposed from the sealing resin body 6. The material of the cooler 10 is, for example, a metal such as copper or aluminum, or an alloy of copper or aluminum. In addition, the cooler 10 may be made of a metal material with excellent heat dissipation properties. Furthermore, the surface of the cooler 10 may be plated.

[0071] ***Explanation of the Effects of the Semiconductor Device 500*** The semiconductor device 500 in Embodiment 1 is a semiconductor device comprising a lead frame 100 on which semiconductor elements 11 are mounted in a row on one side, a sealing resin body 6 formed inside the outer circumference of the lead frame 100, a heat dissipation insulating sheet 9 attached to the side opposite to the side on which the semiconductor elements 11 are mounted, and a cooler 10 attached to the lead frame 100 via the heat dissipation insulating sheet 9. The lead frame 100 comprises N leads 101 whose ends extend outside the sealing resin body 6 and which have an N electrode 1 on one of their ends, and P leads 102 which are provided side by side with a gap between them and the N leads 101, whose ends extend outside the sealing resin body 6 and which have a P electrode 2 on one of their ends. Furthermore, the lead frame 100 is provided with a gap between the N lead 101 and the P lead 102, and includes an AC lead 103 having an AC electrode 3 whose base end extends outside the sealing resin body 6 and whose tip is provided inside the sealing resin body 6, and an insulating support member 8 that connects the AC lead 103 and the N lead 101 and supports the AC lead 103. At least one of the N electrode 1 and the P electrode 2 is provided on the side opposite to the side where the AC electrode 3 is located.

[0072] The semiconductor device 500 in Embodiment 1 has the following configuration: the lead frame 100 has semiconductor elements 11 mounted in a single row on one side, a heat dissipation insulating sheet 9 attached to the opposite side of the side on which the semiconductor elements 11 are mounted, and a cooler 10 attached to the lead frame 100 via the heat dissipation insulating sheet 9. With this configuration, the heat dissipation insulating sheet 9 electrically insulates the lead frame 100 from the cooler 10, while further improving the heat dissipation from the lead frame 100 to the cooler 10 in response to the heat generated from the semiconductor elements 11.

[0073] Furthermore, in the semiconductor device 500 of Embodiment 1, the AC lead 103, which is provided between the N lead 101 and the P lead 102, has its free end connected to the N lead 101 by an insulating support member 8, so that the tip of the AC lead 103 is supported by the insulating support member 8. In other words, the tip of the AC lead 103 is held at the installation height of the insulating support member 8. With this configuration, sagging of the AC lead 103 can be suppressed without providing a suspension lead to the AC lead 103 sandwiched between the N lead 101 and the P lead 102.

[0074] Furthermore, in the semiconductor device 500 of Embodiment 1, the sagging of the tip of the AC lead 103 can be suppressed by providing the insulating support member 8, so there is no need to provide a new suspension lead to the tip of the AC lead 103. Therefore, it is not necessary to secure an insulating distance between at least one of the N electrode 1 and P electrode 2, which are provided on the side opposite to where the AC electrode 3 is located, and the suspension lead, so the size of the sealing resin body 6 can be reduced compared to when a suspension lead is provided to the tip of the AC lead 103. By providing a lead frame 100 with such a configuration, the size of the semiconductor device 500 can be reduced.

[0075] Furthermore, in the lead frame 100 of Embodiment 1, semiconductor elements 11 are mounted in a single row on one side of the P lead 102 and AC lead 103, and the insulating support member 8 is provided on the same side as the side on which the semiconductor elements 11 are mounted. The insulating support member 8 is a ceramic chip component and can be fixed to the lead frame 100 by soldering, so in the process of mounting the semiconductor elements 11 by soldering, the insulating support member 8 can be installed at a predetermined position on the lead frame 100 at the same time as the semiconductor elements 11. With this configuration, the manufacturing of the lead frame 100 becomes easier.

[0076] Furthermore, in Embodiment 1, the N lead 101 branches off from the side facing the AC lead 103 and has a double-ended support lead side projection 14 that protrudes along the tip of the AC lead 103, and the insulating support member 8 connects the double-ended support lead side projection 14 and the AC lead 103. The insulating support member 8 is installed on the upper surface (+Z direction side) of the lead frame 100 in a location where the semiconductor element 11 and bonding wire 15 are not installed. Therefore, since the semiconductor element 11 and bonding wire 15 are not installed on the double-ended support lead side projection 14, it becomes easier to position the insulating support member 8 when attaching it to the lead frame 100. Also, in Embodiment 1, the installation direction of the insulating support member 8 is the X direction, which allows for a smaller longitudinal size of the insulating support member 8 compared to, for example, installing it in an oblique direction.

[0077] ***Explanation of the manufacturing method of the semiconductor device 500*** Next, we will explain the manufacturing method of the semiconductor device 500 using the lead frame 100.

[0078] First, prepare the copper lead frame 100 shown in Figure 1. The lead frame 100 is preferably made of copper or a copper-based alloy, but any material with electrical and thermal conductivity will suffice.

[0079] Next, at least two or more semiconductor elements 11 are placed in a row in the X direction on the upper surface (the +Z direction side) of the P lead 102 and AC lead 103 of the lead frame 100, with a certain spacing between each semiconductor element 11. Simultaneously with the placement of the semiconductor elements 11, an insulating support member 8 is installed on the same side as the placement surface of the semiconductor elements 11, connecting the -X direction end of the AC lead 103 to the end-supported lead side protrusion 14. The semiconductor elements 11 and the insulating support member 8 are then soldered together using a bonding material such as solder and fixed to a predetermined position on the lead frame 100. It is preferable to use a solder material that does not contain lead (Pb). Furthermore, the bonding material is not limited to solder, and silver paste or sintered material may also be used.

[0080] Next, the upper surface (+Z direction side) of the semiconductor element 11, which is placed on the upper surface (+Z direction side) of the P lead 102, and the upper surface (+Z direction side) of the AC lead 103 are connected using a bonding wire 15. Also, the upper surface (+Z direction side) of the semiconductor element 11, which is placed on the upper surface (+Z direction side) of the AC lead 103, and the upper surface (+Z direction side) of the N lead 101 are connected using a bonding wire 15. The bonding wire 15 is preferably made of aluminum, which has high bonding reliability, but copper, gold, or silver may also be used.

[0081] Next, a heat-dissipating insulating sheet 9 is placed on the upper surface (the surface in the +Z direction) of the cooler 10, and the cooler 10 and the heat-dissipating insulating sheet 9 are bonded together. The cooler 10 is made of an aluminum metal plate or metal block.

[0082] Next, with the cooler 10 attached to the lead frame 100 via the heat dissipation insulating sheet 9, it is placed in a predetermined position in the transfer molding die and transferred. During the transfer molding process, the transfer molding resin and the heat dissipation insulating sheet 9 are cured by applying pressure using the transfer molding resin. Note that the transfer molding resin and the heat dissipation insulating sheet 9 do not need to be completely cured after the transfer molding process; they only need to be cured enough to be removed from the transfer molding die after the process. In that case, they may be cured in a curing furnace after being removed from the transfer molding die. The transfer molding resin can be any thermosetting resin, for example, an epoxy resin with an insulating inorganic filler added. Examples of insulating inorganic fillers include aluminum nitride, silicon nitride, boron nitride, alumina (aluminum oxide), crystalline silica (silicon dioxide (SiO2) ２ )) etc. Also, since heat dissipation is not essential for the sealing resin body 6 in Embodiment 1, the resin for transfer molding can contain fused silica (silicon dioxide (SiO) in addition to inorganic fillers. ２ You may also use ))

[0083] Next, the molded product formed by transfer molding is placed in a curing furnace. As shown in Figure 5, the sealing resin body 6 is the state after the molded product formed by transfer molding has been cured in the curing furnace.

[0084] Finally, the outer frame 7 that extends outside the sealing resin body 6, including the tie bars 12 and 13, excluding the N electrode 1, P electrode 2, and AC electrode 3, is removed by tie bar cutting. After tie bar cutting, as shown in Figure 3, a portion of the suspension lead 4 extending in the +Y direction and a portion of the suspension lead 5 extending in the -Y direction remain outside the sealing resin body 6 of the semiconductor device 500.

[0085] Here, we will explain the verification results regarding whether or not sagging of the lead frame 100 can be suppressed when a ceramic chip component is used as the insulating support member 8. The insulating support member 8, which is a ceramic chip component, comes in three sizes: size 1 is 3.2 mm × 1.6 mm × 0.76 mm, size 2 is 3.2 mm × 6.4 mm × 0.76 mm, and size 3 is 3.2 mm × 1.6 mm × 1.2 mm.

[0086] Verification results confirmed that the semiconductor device 500 manufactured using insulating support members 8 of sizes 1, 2, and 3 had no problems with their electrical characteristics. Furthermore, when the heat dissipation insulating sheet 9 was observed from the lower surface (-Z direction side) of the cooler 10 using an ultrasonic flaw detection device, it was confirmed that there were no problems with the adhesion between the heat dissipation insulating sheet 9 and the cooler 10, and between the heat dissipation insulating sheet 9 and the lead frame 100. On the other hand, when the semiconductor device 500 was manufactured without using insulating support members 8, sagging occurred at the -X direction end of the AC lead 103 of the lead frame 100 during the stage of attaching the cooler 10 to the lead frame 100 via the heat dissipation insulating sheet 9. Thus, it was experimentally proven that using ceramic chip components as insulating support members 8 can suppress the sagging of the lead frame 100.

[0087] Next, we will explain the results of testing the adhesion between the insulating support member 8 and the lead frame 100 using epoxy-based adhesives or silicone-based adhesives when an epoxy resin piece is used as the insulating support member 8. First, an epoxy resin piece cured into a rectangular parallelepiped shape with dimensions of, for example, 3.2 mm x 3.2 mm x 1 mm is prepared as the insulating support member 8.

[0088] Next, epoxy adhesive is applied to the upper surface (the +Z direction side) of the protruding part 14 on both ends of the N lead 101 and to the upper surface (the +Z direction side) near the tip of the -X direction end of the AC lead 103, which is a one-end supported lead. Then, as shown in Figure 1, the insulating support member 8, which is a resin piece made of epoxy resin, is placed on the surface coated with epoxy adhesive, with its longitudinal direction aligned with the X direction and both ends resting on it.

[0089] Next, the semiconductor element 11 is soldered to the upper surfaces (+Z direction sides) of the P lead 102 and AC lead 103 using a bonding material such as solder, and fixed to a predetermined position on the lead frame 100. Then, the upper surface (+Z direction side) of the semiconductor element 11, which is placed on the upper surface (+Z direction side) of the P lead 102, and the upper surface (+Z direction side) of the AC lead 103 are electrically connected using a bonding wire 15. Finally, transfer molding is performed and tie bar cutting is carried out to manufacture the semiconductor device 500.

[0090] Similarly, the semiconductor device 500 is manufactured using a silicone-based adhesive instead of an epoxy-based adhesive.

[0091] The verification results confirmed that, in the manufacturing of the semiconductor device 500, there were no problems with the electrical properties regardless of whether an epoxy-based adhesive or a silicone-based adhesive was used to fix the insulating support member 8, which is an epoxy resin piece, to the lead frame 100. Furthermore, when the heat dissipation insulating sheet 9 was observed from the lower surface (the -Z direction side) of the cooler 10 using an ultrasonic flaw detection device, it was confirmed that there were no problems with the adhesion between the heat dissipation insulating sheet 9 and the cooler 10, and between the heat dissipation insulating sheet 9 and the lead frame 100.

[0092] ***Explanation of the effects of the manufacturing method for semiconductor device 500*** The manufacturing method in Embodiment 1 is a method for manufacturing a semiconductor device 500, in which semiconductor elements 11 are mounted in a row on one side of a lead frame 100 and an insulating support member 8 is attached, and a heat dissipation insulating sheet 9 and a cooler 10 are arranged in that order on the side of the lead frame 100 opposite to the side on which the semiconductor elements 11 are mounted, and a sealing resin body 6 that seals the lead frame 100, the heat dissipation insulating sheet 9 and the cooler 10 is molded by transfer molding. With this configuration, sagging of the AC lead 103, which is sandwiched between the N lead 101 and the P lead 102, can be suppressed without providing a suspension lead for the AC lead 103. In addition, the heat dissipation insulating sheet 9 electrically insulates the lead frame 100 and the cooler 10, while dissipating the heat generated from the semiconductor elements 11 to the cooler 10.

[0093] Here, we will explain the relationship between the sagging of the lead frame 100 that occurs when an insulating support member 8 is not used in the manufacturing process of a conventional semiconductor device, and the heat dissipation performance of the semiconductor device 500.

[0094] First, the sagging of the lead frame 100 occurs when it is not connected to the outer frame 7 by a suspension lead or the like, but is a free end, such as the -X direction end of the AC lead 103, which is a one-end supported lead in Embodiment 1. If the lead frame 100 is manufactured without using an insulating support member 8, the -Z direction, which is the opposite side of the surface on which the semiconductor element 11 is installed in Figure 1, becomes the direction of gravity, both during the manufacturing of the lead frame 100 and when it is installed in the mold for transfer molding. Therefore, there is a high possibility that the -X direction end of the AC lead 103 will sag due to its own weight before the transfer molding stage.

[0095] If the end of the AC lead 103 on the -X side sags, when attaching the lead frame 100 to the opposite side of the heat dissipation insulating sheet 9 that is bonded to the cooler 10, the corner of the sagging end of the AC lead 103 on the -X side may come into contact with the heat dissipation insulating sheet 9, potentially damaging the heat dissipation insulating sheet 9. Furthermore, the sagging end of the AC lead 103 on the -X side may create a gap between the AC lead 103 and the heat dissipation insulating sheet 9.

[0096] This can lead to a deterioration in the adhesion between the AC lead 103 and the heat-dissipating insulating sheet 9, potentially reducing the heat dissipation performance of the heat-dissipating insulating sheet 9. Furthermore, when power is applied to the semiconductor device 500, the gap between the AC lead 103 and the heat-dissipating insulating sheet 9 can cause a discharge phenomenon where dielectric breakdown occurs in the gas that enters the gap, causing current to flow and potentially adversely affecting the semiconductor device 500.

[0097] However, by connecting the N lead 101 and the AC lead 103 with the insulating support member 8, sagging of the -X side end of the AC lead 103 can be suppressed, thereby preventing damage to the heat dissipation insulating sheet 9 and poor adhesion between the lead frame 100 and the heat dissipation insulating sheet 9, and improving the heat dissipation performance of the heat dissipation insulating sheet 9.

[0098] Furthermore, in Embodiment 1, the lead frame 100 and the cooler 10 are integrally transferred and molded with a heat dissipation insulating sheet 9 sandwiched between them. In transfer molding, the resin for transfer molding and the heat dissipation insulating sheet 9 are cured under pressure, so both the adhesion between the lead frame 100 and the heat dissipation insulating sheet 9, and the adhesion between the heat dissipation insulating sheet 9 and the cooler 10 are improved. As a result, in Embodiment 1, insulation between the lead frame 100 and the cooler 10 is not required by another method, and there is no need to use thermal grease, and thermal resistance can be reduced even further than when thermal grease is used.

[0099] Embodiment 2. The configuration of the lead frame 200 in Embodiment 2 will be described. The lead frame 200 according to Embodiment 2 differs from the lead frame 100 according to Embodiment 1 in that it is equipped with N leads 201 instead of N leads 101, and the arrangement of the insulating support members 8 is different. The other configurations of the lead frame 200 are the same as or equivalent to those of the lead frame 100, and redundant explanations will be omitted.

[0100] Figure 6 is a top view of the lead frame in Embodiment 2 before tie bar cutting (after semiconductor elements are mounted and bonding wires are installed). The lead frame 200 in Embodiment 2 includes an N lead 201 without the end-support lead side protrusions 14. The lead frame 200 is also provided with an insulating support member 8 that connects the top surface (+Z direction side) of the N lead 201 and the top surface (+Z direction side) near the tip of the -X direction end of the AC lead 103, with the longitudinal direction aligned with the Y direction.

[0101] In the second embodiment, the lead frame 200 has the following configuration: the AC lead 103, which is provided between the N lead 201 and the P lead 102, is supported by the insulating support member 8, for example, by the free end of its tip being connected to the N lead 201 by the insulating support member 8. In other words, the tip of the AC lead 103 is held at the installation height of the insulating support member 8. With this configuration, sagging of the AC lead 103 can be suppressed without providing a suspension lead to the AC lead 103 sandwiched between the N lead 201 and the P lead 102. Furthermore, since sagging of the tip of the AC lead 103 can be suppressed by providing the insulating support member 8, there is no need to provide a new suspension lead to the tip of the AC lead 103. Therefore, since it is not necessary to ensure an insulating distance between at least one of the N electrode 1 and P electrode 2, which are provided on the side opposite to the side where the AC electrode 3 is located, and the suspension lead, the size of the sealing resin body 6 that covers the inside of the outer circumference of the lead frame 200 can be reduced compared to when a suspension lead is provided at the tip of the AC lead 103.

[0102] In Embodiment 2, the insulating support member 8 was connected in the Y direction, but it is not limited to that direction; for example, it may be connected in an oblique direction. The insulating support member 8 can be installed on the same surface of the lead frame 200 as the surface on which the semiconductor element 11 is installed, but in a location where the semiconductor element 11 and bonding wire 15 are not installed. Furthermore, the location where the insulating support member 8 is installed is not limited to the tip of the AC lead 103, but may be anywhere other than the tip of the AC lead 103.

[0103] Embodiment 3. The configuration of the lead frame 300 in Embodiment 3 will be described. The lead frame 300 according to Embodiment 3 differs from the lead frame 100 according to Embodiment 1 in that it is equipped with an N lead 301 instead of an N lead 101, and the arrangement of the insulating support member 8 is different. The other configurations of the lead frame 300 are the same as or equivalent to those of the lead frame 100, and redundant explanations will be omitted.

[0104] Figure 7 is a top view of the lead frame in Embodiment 3 before tie bar cutting (after semiconductor elements are mounted and bonding wires are installed). The lead frame 300 of Embodiment 3 includes an N lead 301 without the end-support lead side protrusions 14. The N lead 301 has an N electrode 1 at the end on the +X side and is connected to the outer frame 7 via the N electrode 1. The lead frame 300 is also provided with an insulating support member 8 that connects the upper surface (on the +Z side) of the P lead 102 and the upper surface (on the +Z side) near the tip of the -X side end of the AC lead 103, with its longitudinal direction aligned with the Y direction.

[0105] In the third embodiment, the lead frame 300 has the following configuration: the AC lead 103, which is provided between the N lead 301 and the P lead 102, is supported by the insulating support member 8, for example, by the free end of its tip being connected to the P lead 102 by the insulating support member 8. In other words, the tip of the AC lead 103 is held at the installation height of the insulating support member 8. With this configuration, sagging of the AC lead 103 can be suppressed without providing a suspension lead to the AC lead 103 sandwiched between the N lead 301 and the P lead 102. Furthermore, since sagging of the tip of the AC lead 103 can be suppressed by providing the insulating support member 8, there is no need to provide a new suspension lead to the tip of the AC lead 103. Therefore, since it is not necessary to ensure an insulating distance between the P electrode 2, which is provided on the side opposite to where the AC electrode 3 is located, and the suspension lead, the size of the sealing resin body 6 that covers the inside of the outer circumference of the lead frame 300 can be reduced compared to when a suspension lead is provided at the tip of the AC lead 103.

[0106] In Embodiment 3, the insulating support member 8 is connected in the Y direction, but it is not limited to this direction; for example, it may be connected in an oblique direction. The insulating support member 8 can be installed on the same surface of the lead frame 300 as the surface on which the semiconductor element 11 is installed, but in a location where the semiconductor element 11 and bonding wire 15 are not installed. Furthermore, the location where the insulating support member 8 is installed is not limited to the tip of the AC lead 103, but may be other than the tip of the AC lead 103.

[0107] Embodiment 4. The configuration of the lead frame 400 in Embodiment 4 will be described. The lead frame 400 according to Embodiment 4 differs from the lead frame 200 according to Embodiment 2 in that it is equipped with a P lead 402 instead of a P lead 102. The other configurations of the lead frame 400 are the same as or equivalent to those of the lead frame 200, and redundant explanations will be omitted.

[0108] Figure 8 is a top view of the lead frame before tie bar cutting in Embodiment 4 (after semiconductor elements are mounted and bonding wires are installed). The lead frame 400 of Embodiment 4 is equipped with a P lead 402 having a P electrode 2 at the end on the +X side. The P lead 402 is connected to the outer frame 7 via the P electrode 2.

[0109] In the fourth embodiment, the lead frame 400 has the following configuration: the AC lead 103, which is provided between the N lead 201 and the P lead 402, is supported by the insulating support member 8, for example, by having its free end connected to the N lead 201 by the insulating support member 8. In other words, the tip of the AC lead 103 is held at the installation height of the insulating support member 8. With this configuration, sagging of the AC lead 103 can be suppressed without providing a suspension lead to the AC lead 103 sandwiched between the N lead 201 and the P lead 402. Furthermore, since sagging of the tip of the AC lead 103 can be suppressed by providing the insulating support member 8, there is no need to provide a new suspension lead to the tip of the AC lead 103. Therefore, since it is not necessary to ensure an insulating distance between the N electrode 1, which is provided on the side opposite to where the AC electrode 3 is located, and the suspension lead, the size of the sealing resin body 6 that covers the inside of the outer circumference of the lead frame 400 can be reduced compared to when a suspension lead is provided at the tip of the AC lead 103.

[0110] Furthermore, the insulating support member 8 can be installed on the same surface of the lead frame 400 as the surface on which the semiconductor element 11 is installed, but in a location where the semiconductor element 11 and bonding wire 15 are not installed. In addition, the location where the insulating support member 8 is installed is not limited to the tip of the AC lead 103, but may be anywhere other than the tip of the AC lead 103.

[0111] 1 N electrode (first electrode) 2 P electrode (second electrode) 3 AC electrode (third electrode) 4 Suspension lead 5 Suspension lead 6 Encapsulating resin body 7 Outer frame 8 Insulating support member 9 Heat dissipation insulating sheet 10 Cooler 11 Semiconductor element 12 Tie bar 13 Tie bar 14 Protrusion on both end support lead side 15 Bonding wire 16 Metal plate 100, 200, 300, 400 Lead frame 500 Semiconductor device 101, 201, 301 N lead (first both end support lead) 102, 402 P lead (second both end support lead) 103 AC lead 103 (one end support lead)

Claims

1. A lead frame comprising: a first double-ended support lead having both ends connected to an outer frame and a first electrode on one of its ends; a second double-ended support lead provided at a distance from the first double-ended support lead, having both ends connected to the outer frame and a second electrode on one of its ends; a single-ended support lead provided at a distance from the first double-ended support lead and the second double-ended support lead, having a third electrode whose base end is connected to the outer frame and whose tip is a free end; and an insulating support member connecting the single-ended support lead and the first double-ended support lead to support the single-ended support lead, wherein at least one of the first electrode and the second electrode is provided on the side opposite to the side on which the third electrode is located.

2. The lead frame according to claim 1, wherein semiconductor elements are mounted in a single row on one side of the one-end supported lead and the first double-end supported lead or the second double-end supported lead, and the insulating support member is provided on the same side as the side on which the semiconductor elements are mounted.

3. The lead frame according to claim 1 or 2, wherein the first double-ended support lead has a double-ended support lead side projection that branches off from the side facing the one-ended support lead and protrudes along the tip of the one-ended support lead, and the insulating support member connects the double-ended support lead side projection and the one-ended support lead.

4. The lead frame according to any one of claims 1 to 3, wherein the insulating support member is a ceramic chip component.

5. The lead frame according to claim 4, wherein the chip component is either aluminum nitride or silicon nitride and has metal pieces at both ends.

6. The lead frame according to any one of claims 1 to 3, wherein the insulating support member is a resin piece made of epoxy resin or silicone resin.

7. A lead frame on which semiconductor elements are mounted in a row on one side; a sealing resin body formed inward from the outer circumference of the lead frame; a heat dissipation insulating sheet attached to the side opposite to the side on which the semiconductor elements are mounted; and a cooler attached to the lead frame via the heat dissipation insulating sheet, wherein the lead frame comprises: a first double-ended support lead whose ends extend outward from the sealing resin body and has a first electrode on one of its ends; a second double-ended support lead provided at a distance from the first double-ended support lead, whose ends extend outward from the sealing resin body and has a second electrode on one of its ends; a one-ended support lead provided at a distance from the first double-ended support lead and the second double-ended support lead, whose base end has a third electrode extending outward from the sealing resin body and whose tip is provided inside the sealing resin body; and an insulating support member connecting the one-ended support lead and the first double-ended support lead and supporting the one-ended support lead. A semiconductor device in which at least one of the first electrode and the second electrode is provided on the side opposite to the side on which the third electrode is located.

8. The semiconductor device according to claim 7, wherein the semiconductor element is mounted on the one-end support lead and the first double-end support lead or the second double-end support lead, and the insulating support member is provided on the same surface as the surface on which the semiconductor element is mounted.

9. The semiconductor device according to claim 7 or 8, wherein the first double-ended support lead has a double-ended support lead side projection that branches off from the side facing the one-ended support lead and protrudes along the tip of the one-ended support lead, and the insulating support member connects the double-ended support lead side projection and the one-ended support lead.

10. A method for manufacturing a semiconductor device according to claim 8, wherein the semiconductor elements are mounted in a row on one side of the lead frame and the insulating support member is attached, and the heat dissipation insulating sheet and the cooler are arranged in that order on the side of the lead frame opposite to the side on which the semiconductor elements are mounted, and the sealing resin body that seals the lead frame, the heat dissipation insulating sheet and the cooler is molded by transfer molding.

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